TY - GEN A1 - Weiss, Nils T1 - Reverse Engineering and Weaponizing OBD Dongles T2 - Automotive Security Research Group, Stuttgart, Germany 2019, Meeting 22 Y1 - 2019 UR - https://www.meetup.com/de-DE/Automotive-Security-Research-Group-ASRG/events/261796924/ ER - TY - GEN A1 - Krämer, Stefan T1 - Effects of Arbitrary Hardware Faults on Multicore Scheduling in Safety-critical Applications – Evaluation by enhanced Markov models and discrete event simulation T2 - 2014 PESW - The 2nd Prague Embedded Systems Workshop, June 2014 Y1 - 2014 UR - https://pesw.fit.cvut.cz/2014/presentations/pesw2014_Kramer.pdf ER - TY - CHAP A1 - Schubert, Martin J. W. T1 - Mixed-Signal Event-Driven Simulation of a Phase-Locked Loop T2 - IEEE/VIUF International Workshops on Behavioral Modeling and Simulation (BMAS'99), October 4-6 1999, Orlando, Florida, USA N2 - The mixed-signal event-driven (MixED) simulationalgorithm using standard VHDL is capable of modelinga number of analog and mixed-signal problems in digital circuits, e.g. RCL networks representing pads or wires, charge pumps, dynamic logic, voltage-controlledoscillators, phase-locked loops, etc. Important featuresare single-kernel simulation as well as rapid A/D andD/A interfacing. This paper demonstrates the simulation of a phase-locked loop (PLL), which is one of the most interesting applications of the MixED method. Many digital designs contain a PLL as only mixed-signal building block. The MixED method allows to simulate such designs with standard VHDL. KW - mixed-signal event-drivensimulation KW - standard VHDL KW - analog models KW - PLL Y1 - 1999 UR - https://hps.hs-regensburg.de/~scm39115/homepage/research/mixed/mixed_publications/1999_bmas_pll.pdf ER - TY - CHAP A1 - Schubert, Martin J. W. T1 - VHDL Based Simulation of a Sigma-Delta A/D Converter T2 - EEE/ACM International Workshop on Behavioral Modeling and Simulation (BMAS2000), October 19-20 2000, Orlando, Florida, USA, prodeedings N2 - The VHDL based mixed-signal event-driven (MixED) simulation method is employed to simulate a sigma-delta modulator for A/D conversion. Results are verified by experimental data and comparison to PSpice-AD simulations. Y1 - 2000 U6 - https://doi.org/10.1109/BMAS.2000.888367 ER - TY - CHAP A1 - Schubert, Martin J. W. T1 - VHDL Based Simulation of a Delta-Sigma A/D Converter Clocked with a Phase-Locked Loop T2 - Design, Automation and Test in Europe, DATE'2001 Conference, March 13-16 2001, Munich N2 - The VHDL based mixed-signal event-driven (MixED) simulation method is employed to simulate a comprehensive system containing a number of mixed-signal building blocks: an analog waveform generator, a phase-locked loop and two ∆Σ modulators for A/D conversion. Y1 - 2001 UR - https://hps.hs-regensburg.de/~scm39115/homepage/research/mixed/mixed_publications/2001_date_pll_sigmadelta.pdf ER - TY - JOUR A1 - Schubert, Martin J. W. T1 - An Analog Node Model for VHDL Based Simulation of RF Integrated Circuits JF - IEEE Transactions on Circuits and Systems I, Regular Papers N2 - This paper describes a very-high-speed integrated-circuit hardware description language (VHDL)-based analog-node model, an associated driver component for the mixed-signal event-driven (MixED) simulation technique, and some primitive device models applied to radio-frequency integrated circuits. With the presented MixED method, analog circuits are modeled as a composition of controlled sources. Unlike other VHDL-based analog simulation methods, these MixED sources compute not only a real number representing an output voltage but also an output impedance. This allows the outputs of several MiXED sources to be connected in order to drive the same node signal n . The voltage of this record-type signal is automatically computed at its element n . u by resolution functions in compliance with Kirchhoff's current law. The data structure of the node signal n , its self-defined resolution functions, and an associated driver component are presented and discussed to meet different simulation requirements, such as speed, versatility, current accuracy, and adaptive time stepping. Several examples demonstrate how to behaviorally model mixed-signal components with this method with an emphasis on the simulation of a heterodyne receiver. Simulation speeds are compared to VHDL-AMS tools. KW - Integrated circuit modeling KW - Radio frequency KW - Analog integrated circuits KW - Radiofrequency integrated circuits KW - Computational modeling KW - Circuit simulation KW - Voltage KW - Signal resolution KW - Hardware design languages KW - Driver circuits Y1 - 2009 U6 - https://doi.org/10.1109/TCSI.2009.2027799 VL - 56 IS - 12 SP - 2717 EP - 2727 ER - TY - CHAP A1 - Lee, Wai-Kong A1 - Schubert, Martin J. W. A1 - Ho, Stanley Jian-Qin T1 - Multi-source energy harvesting and storage for floating wireless-sensor-network nodes T2 - 2016 IEEE Industrial Electronics and Applications Conference (IEACon 2016), 20.-22. Nov. 2016, Kota Kinabalu, Malaysia Y1 - 2016 SN - 9781509009268 ER - TY - CHAP A1 - Schubert, Martin J. W. T1 - System Contemplations for Precision Irrigation in Agriculture T2 - AIP Conference Proceedings N2 - This communication contemplates political, biological and technical aspects for efficient and profitable irrigation in sustainable agriculture. A standard for irrigation components is proposed. The need for many, and three-dimensionally distributed, soil measurement points is explained, thus enabling the control of humidity in selected layers of earth. Combined wireless and wired data transmission is proposed. Energy harvesting and storage together with mechanical sensor construction are discussed. Y1 - 2017 SN - 9780735414969 U6 - https://doi.org/10.1063/1.4979393 VL - 1828 IS - 1 ER - TY - CHAP A1 - Schubert, Martin J. W. A1 - Seign, Stefan A1 - Dai, Q. A1 - Hinterseer, Sebastian A1 - Pielmeier, F. A1 - Pietsch, Alexander A1 - Seebauer, C. A1 - Weiß, Josef A1 - Yu, C. A1 - Zenger, Stefan T1 - Capacitive Sensor Technology for Soil Moisture Monitoring Networks T2 - 24th IEEE International Conference on Electronics, Circuits and Systems (ICECS), 5-8 Dec. 2017, Batumi, Georgia N2 - A sensor technology for tracking soil-moisture in agricultural fields is presented. A linear measurement method was developed to satisfy the need for cheap sensors with wide range of capacitance change such as factor 30. A combined wired and wireless network transmits data to a server. Various battery aspects are compared with respect to use in agriculture. Y1 - 2017 U6 - https://doi.org/10.1109/ICECS.2017.8292018 SP - 190 EP - 193 ER - TY - PAT A1 - Schubert, Martin J. W. A1 - Seign, Stefan T1 - Arrangement for Measuring Capacitance Y1 - 2016 ER - TY - JOUR A1 - Schubert, Martin J. W. T1 - 70V-to-5V Differential CMOS Input Interface JF - IEE Electronic Letters Y1 - 1994 U6 - https://doi.org/10.1049/el:19940235 VL - 30 IS - 4 SP - 296 EP - 297 ER - TY - PAT A1 - Schubert, Martin J. W. T1 - Verfahren zur Simulation von Netzwerken auf einer ereignisgesteuerten Zeitachse mittels verteilter, lokaler Iteration Y1 - 1996 ER - TY - CHAP A1 - Schubert, Martin J. W. T1 - Mixed Signal Modeling in VHDL by Distributed Local Iteration T2 - VHDL Form, Toledo, Spain, April 20-24, 1997 Y1 - 1997 ER - TY - CHAP A1 - Schubert, Martin J. W. T1 - Mixed Analog-Digital Signal Modeling Using Event-Driven VHDL T2 - X Brazilian Symposium on Integrated Circuit Design (SBCCI'97), August 25-27 1997, Porto Alegre, Brazil N2 - A method for solving networks containing generic analog components such as resistors, capacitors and inductors onan event driven time axis using digital VHDL is presented. The components are modeled as complex state machines communicating with their neighbors using INOUT type ports. The method takes advantage of simulation deltas to iterate without simulation-time consumption. A limited range of implicit equations can be solved this way. Y1 - 1997 UR - http://citeseerx.ist.psu.edu/viewdoc/download;jsessionid=50F6F0DA594FB90976CC1474581BC139?doi=10.1.1.508.3657&rep=rep1&type=pdf SP - 77 EP - 86 ER - TY - PAT A1 - Schubert, Martin J. W. T1 - Feedback-nach-Feedforward-Transformation zur Verhaltensmodellierung rückgekoppelter Verstärker Y1 - 1997 ER - TY - CHAP A1 - Schubert, Martin J. W. T1 - Operational Amplifier Modeling Using Event-Driven VHDL T2 - IEEE/VIUF International Workshops on Behavioral Modeling and Simulation (BMAS'97), October 20/21 1997, Washington D.C., USA N2 - A method to model high-gain feedback-loop analog amplifiers on an event driven timeaxis is presented. The demonstrator is coded in digital VHDL’93. In the event-driven scheme any node in the network must converge „on its own“ based on the information delivered from its neighbors, as no overall matrix is set up. For this reason signalloops with a loop gain larger than one are typically unstable. This communication presents a numerically stable generic model for high gain amplifiers with a userdefined feedback network. Non-ideal effects like offset or finite gain can be taken into account. Y1 - 1997 UR - https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.495.5356&rep=rep1&type=pdf ER - TY - CHAP A1 - Bartsch, Ernst A1 - Schubert, Martin J. W. T1 - Mixed Analog-Digital Circuit Modeling Using Event-Driven VHDL T2 - IEEE/VIUF International Workshops on Behavioral Modeling and Simulation (BMAS'97), Ocotober 20/21 1997, Washington D.C., USA N2 - The mixed-signal event-driven (MixED) method developed to simulate small portions of analog circuitry within a digital environment is demonstrated in a mixed signal application. The MixED models using concurrent iteration to account for analog nodes were coded and run in standard VHDL’93. Networks containing linear components such as sources, resistors, capacitors, inductors and operational amplifiers are presented. The possibility to manipulate resistors during runtime is used to simulate switches. Y1 - 1997 UR - https://hps.oth-regensburg.de/scm39115/homepage/research/mixed/mixed_publications/1997_bmas_circuit.pdf ER - TY - CHAP A1 - Miedl, Christian A1 - Braun, Jürgen T1 - Powertrain and electric system design of a 800-volt all-electric car T2 - European Conference on Nanoelectronics and Embedded Systems for Electric Mobility, eMotion in Smart Cities, 24.-28. September, 2012, Bologna, Italy Y1 - 2012 ER - TY - CHAP A1 - Hofmann, Gerhard A1 - Scharfenberg, Georg T1 - Applicability of the ISO 26262 for functional safety for motorbikes T2 - 2014 International Conference on Applied Electronics, 9-10 Sept. 2014, Pilsen, Czech Republic N2 - This article deals with the question to what extent the automotive standard for functional safety ISO 26262 is also applicable to motorbikes. It examines thereby, on the one hand where to find comparable criteria between cars and motorbikes from the standpoint of functional safety, and, on the other hand, where differences between the automobile and the motorbike must be considered. It shows the extent to which the safety-related automotive standard is applicable to motorbikes. Furthermore, the differences are determined, which must lead to the consequence of a new “state of the art” and to a new standard for motorbikes. On the example of a light function the new MSIL classification gets applied. In this article, the motorbike is viewed as a whole. For the most parts the standard is also valid for scooters. KW - Automobiles KW - Automotive engineering KW - Functional Safety KW - ISO 26262 KW - ISO Standards KW - motorbike KW - Motorcycles KW - MSIL KW - safety Y1 - 2014 U6 - https://doi.org/10.1109/AE.2014.7011679 SP - 107 EP - 112 PB - IEEE ER - TY - CHAP A1 - Schiek, Roland T1 - Self-phase modulation in lithium niobate waveguides T2 - 2014 International Conference Laser Optics, title=Self-phase modulation in lithium niobate waveguides, 30 June-4 July 2014, St. Petersburg, Russia N2 - Self-phase modulation in lithium niobate wave-guides with cascaded quadratic and cubic nonlinearities is characterized by comparison of amplitude and phase of input and output pulse envelopes and spectra. Cubic nonlinear susceptibility coefficients of lithium niobate were determined from the measured nonlinear phase shifts. KW - Frequency measurement KW - Frequency modulation KW - lithium niobate KW - nonlinear susceptibility KW - self-phase modulation KW - Wavelength measurement Y1 - 2014 U6 - https://doi.org/10.1109/LO.2014.6886403 PB - IEEE ER - TY - CHAP A1 - Hofmeister, Justus A1 - Krebs, Stefan A1 - Schickhuber, Gerald A1 - Scharfenberg, Georg T1 - Design and development of a Pico Hydro turbine system for the use in developing countries T2 - 2015 5th International Youth Conference on Energy (IYCE), 27-30 May 2015, Pisa, Italy N2 - In Sub-Saharan Africa less than 10% of the rural population has access to electricity [1]. Stand-alone power systems (SPS) can be a solution to the problem of the lack of electricity, which highlights challenges such as modules installation costs as well as the sufficient knowledge required for installing, maintaining and operating such systems. With this fact in mind, a 250 W Low Head turbine system was developed and optimized to have the advantage of the simplicity of installation and a construction from readily available materials. This design scores the electrical efficiency of 60%, reduces manufacturing unit coast to 130 € and takes into account the necessity of providing a clear and simple manual describing the manufacturing and installation. A better version of the load controller, using a microcomputer is under current development. Mounting of the system have been simplified to reduce the amount of construction material required to provide uninterrupted 230 V at 50 Hz AC or optional 12 V DC power supply. Current efforts aim on transferring the required mechanical and electrical knowledge for building, programming, installing and maintaining such system to schools in targeted countries. This project doesn’t only provide people in rural developing countries a gleam of hope to catch up with the developed countries, but also helps students to use their theoretical knowledge to realize practical applications. KW - Coils KW - Development Cooperation KW - Generators KW - Hydraulic turbines KW - Low Head KW - Pico Hydro KW - Propellers KW - Shafts KW - Synchronous Generator KW - Water Turbine KW - Windings Y1 - 2015 U6 - https://doi.org/10.1109/IYCE.2015.7180767 SP - 1 EP - 7 PB - IEEE ER - TY - CHAP A1 - Rösel, Birgit A1 - Köhler, Thomas T1 - First results of a new digitalized concept for teaching control theory as minor subject at a university of applied science T2 - 2018 IEEE Global Engineering Education Conference (EDUCON), 17-20 April 2018, Santa Cruz de Tenerife, Spain N2 - This paper presents a digitalized concept for teaching control theory as minor subject with an integrated approach for lectures, exercises and practical sessions and first results of the implementation at the department of electrical engineering at the OTH Regensburg. The concept uses activating methods like blended learning and possibilities of digitalization of teaching implementing Just in Time Teaching and Peer Instruction. The base of the new concept is the idea of constructive alignment. Furthermore this paper presents the feedback of the students along with an accompanying scientific research over several semesters. The data obtained from the presented module are compared with the data from other blended learning approaches in Germany. KW - Blended Learning KW - constructive alignment KW - Control theory KW - Electrical engineering KW - Electronic learning KW - Just in Time Teaching KW - Task analysis KW - taxonomy KW - teaching text Y1 - 2018 U6 - https://doi.org/10.1109/EDUCON.2018.8363217 SP - 118 EP - 125 PB - IEEE ER - TY - CHAP A1 - Haumer, Anton A1 - Kral, Christian T1 - Enhancements of Electric Machine Models: The EMachines Library T2 - Proceedings of the 11th International Modelica Conference, Versailles, France, September 21-23, 2015 N2 - Transient models of multi phase electric machines are already implemented in the Modelica Standard Library (MSL). However, advanced effects like saturation and skin effect are not taken into account. As an extension to the MSL models, the new EMachines library is presented. This package will be released as a supplemental library to the commercial EDrives library. The particular focus of this paper is on the deep bar effect of induction machines. A comparison of simulation results demonstrates the influence of the skin effect on the operational behavior of the machines. At the end of this publication further developments of the EMachines library will be outlined. KW - multi phase electric machines KW - induction machines KW - squirrel cage KW - deep bar effect KW - skin effect Y1 - 2015 U6 - https://doi.org/10.3384/ecp15118509 VL - 118 SP - 509 EP - 515 PB - Linköping University Electronic Press ER - TY - CHAP A1 - Schmidt, Hans-Peter A1 - Fuchs, Andreas A1 - Fuchs, Stefan T1 - Simultaneous contact less charging of multiple electric vehicles: Contact less power and data transfer for multiple distributed loads T2 - 2014 4th International Electric Drives Production Conference ( 30 Sept.-1 Oct. 2014, Nuremberg, Germany N2 - A design of a 3-phase inductive power and data transfer for multiple stationary loads is proposed. It focuses on stable load voltages while minimizing electromagnetic interference. Loads are contactless charging units of electric vehicles at car parks. Physical properties of the inductive couplers are modelled via 3-D FEM and lumped parameters are used for system studies. Design principles are verified at laboratory scale with a purpose built test stand. KW - charging infrastructure KW - Coils KW - contact less charging KW - Couplers KW - Couplings KW - Data transfer KW - Electric vehicles KW - electro mobility KW - Feeds KW - multiple stationary loads KW - Windings Y1 - 2014 U6 - https://doi.org/10.1109/EDPC.2014.6984435 SP - 1 EP - 3 PB - IEEE ER - TY - CHAP A1 - Grothmann, Benjamin A1 - Poelsterl, Thomas A1 - Gerling, Dieter T1 - Online compensation of current sensor gain-faults for safety-relevant IPM-drives T2 - 2017 IEEE Transportation Electrification Conference and Expo (ITEC), 22-24 June 2017, Chicago, IL, USA N2 - Detection and compensation of current sensor gain-faults regardless of the operating-point is a crucial aspect for safety-relevant servo-drives. This paper presents and investigates a new direct phase-gain re-balancing methodology, especially suited for interior permanent magnet machine (IPM) drives mostly operating at low speed-ranges including standstill. The proposed model-based approach utilizes high-frequency signal-injection (HFI) to facilitate fast and persistent sensor monitoring for any operating state of the drive. No additional sensing hardware is required. Extraction of the HFI-phase-current response enables detection and immediate compensation of sensor gain-faults. Implementation aspects of the proposed concept are discussed thoroughly. Experimental results are presented to prove and investigate robustness, reliability and fault-tolerant performance. KW - Acoustic noise KW - Current measurement KW - Frequency synchronization KW - Hardware KW - Phase measurement KW - Signal to noise ratio KW - Torque Y1 - 2017 U6 - https://doi.org/10.1109/ITEC.2017.7993355 SP - 701 EP - 706 PB - IEEE ER - TY - CHAP A1 - Grimm, Alexander A1 - Haumer, Anton T1 - EMOTH The EMobility Library of OTH Regensburg T2 - Proceedings of the 12th International Modelica Conference, Prague, Czech Republic, May 15-17, 2017 N2 - The importance of E-Mobility is rapidly increasing, not only for private vehicle traffic but also for public transport. In and around Regensburg, Germany there are a lot of automotive companies. Therefore E-Mobility is an important topic in the curriculum of several courses of study at the East-Bavarian Technical University of Applied Sciences Regensburg (OTH). One Master of Applied Research student at OTH has chosen the topic to develop an open-source simulation tool for electric vehicles – the EMOTH Library – based on Modelica and to refine several aspects of the library during the one and a half year of the master course. After one semester, the basic version of the library is available and will be presented in this paper. Y1 - 2017 U6 - https://doi.org/10.3384/ecp17132285 SP - 285 EP - 290 PB - Linköping University Electronic Press ER - TY - CHAP A1 - Schneider, Michael A1 - Haumer, Anton A1 - Köckeis, Rupert T1 - Modelling and Simulation of the passive Structure of a 5-Axis-Milling Machine with rigid and flexible bodies for evaluating the static and dynamic behaviour T2 - Proceedings of the 12th International Modelica Conference, Prague, Czech Republic, May 15-17, 2017 N2 - Most of the mechanical simulations for industrial usage are done by finite element (FE-) analysis. Milling machines are mechatronic systems, combining electrical, mechanical and control components for machining certain materials. Modelica provides a powerful and strong tool to simulate different physical ares in one model. For this usage a mechanical model of a 5-Axis-Milling Machine is implemented with rigid and flexible bodies. Specific attention will be paid to which components can be modelled rigid without significant deviation in accordance to the real behaviour of the machine. Two classes of implementing flexible bodies in multi body systems are given by the flexible bodies Library, advantages and disadvantages of both classes will be evaluated. At the end a comparision of the static and dynamic behaviour of the passive structure of the model in contrast to a FE-analysis is given. KW - clay modelling KW - multibody system KW - Milling machine KW - flexible body Y1 - 2017 U6 - https://doi.org/10.3384/ecp17132389 SP - 389 EP - 395 PB - Linköping University Electronic Press ER - TY - CHAP A1 - Schlal, Sebastian A1 - Wicke, Markus A1 - Zahner, Thomas A1 - Lang, Kurt-Jürgen T1 - Evaluation of thermal solder joint quality and thermal performance of PCBs by using standard measurement equipment T2 - 20th International Workshop on Thermal Investigations of ICs and Systems, 24-26 Sept. 2014, Greenwich, UK N2 - By using more powerful LEDs a good thermal management is becoming more and more important. Here usually the thermal interconnects have to be in focus. Therefore a simple and rapid measurement method for the thermal check of the solder joint in a high volume production is necessary. A standard thermal resistance measurement is very time consuming due to the calibration of each device. By using thermal characterized reference devices it is possible to skip the time consuming part. Furthermore, a simple methodology for evaluating the thermal performance of the various metal core PCB (MCPCB) materials and construction is required during development. In this paper we will present how we successfully demonstrated that this new method offers an opportunity to determine the thermal performance of a high power QFN LED on different types of isolated metal substrate (IMS) and with a standard SMU [1] (source measurement units). KW - Electrical resistance measurement KW - Light emitting diodes KW - Semiconductor device measurement KW - Soldering KW - standards KW - Thermal resistance Y1 - 2014 U6 - https://doi.org/10.1109/THERMINIC.2014.6972522 SP - 1 EP - 5 PB - IEEE ER - TY - CHAP A1 - Rösel, Birgit T1 - Erfahrungen mit einem Konzept für eine Kombination aus Vorlesung, Übung und Praktikum unter Verwendung aktivierender Lehrmethoden BT - Tagungsband zum Forum der Lehre an der TH Ingolstadt, 16. April 2018 T2 - Forum der Lehre : Digitale Akzente setzen N2 - Im Beitrag wird das Konzept mit JiTT-Einheiten, klassischen Vorlesungen, Übungen und dem Praktikum vorgestellt. Insbesondere erfolgt eine Beschreibung der Struktur der Lehrtexte und der zugehörenden Fragen. Nachfolgend werden Herausforderungen bei der Umsetzung des Konzeptes dargestellt. Betrachtet wird hier die Entscheidung über Anzahl der Lehrtexte sowie die Erstellung derselben durch die Autorin sowie die Umsetzung des gesamten Konzeptes auf einer Online-Plattform. Abschließend werden die Reaktionen und Rückmeldungen der Studierenden zu dem neuen Lehrkonzept dargestellt. Basis sind hierbei die Auswertung der Beantwortung der Fragen in den JiTT-Einheiten sowie Befragungen der Studierenden mit verschiedenen Fragebögen. Y1 - 2018 SP - 33 EP - 41 ER - TY - RPRT A1 - Rösel, Birgit T1 - Blended Learning für Regelungstechnik als Nebenfach mit JiTT N2 - Studierende bearbeiten in ihrem Tempo Lehrtexte und dazugehörige Fragen auf einer Online-Lernplattform, um sich auf den Präsenztermin vorzubereiten. Bei diesem Format des Just in Time Teaching (JiTT) wird ein integratives Konzept von Theorievermittlung, Übung und Praktikum verwirklicht. Y1 - 2018 UR - https://www.e-teaching.org/community/digital-learning-map/blended-learning-fuer-regelungstechnik-als-nebenfach-mit-jitt ER - TY - JOUR A1 - Sindersberger, Dirk A1 - Prem, Nina A1 - Monkman, Gareth J. T1 - Self-assembling structure formation in low-density magnetoactive polymers JF - Journal of Applied Polymer Science N2 - The formation of microstructures in magnetoactive polymers (MAPs) is a recently discovered phenomenon found only with very low filler particle concentrations (less than 3 wt %). Due to the degassing process, filler particles collect around an ascending bubble, which dissolves at a certain point leaving particulate rings within the matrix. The formation of toroidal microstructures commences as filler concentration approaches 1 wt %. The development of coherent parallel aligned rings with a compact order continues as particle concentrations increase toward 2 wt %. Between 2 and 3 wt % capillary doublets develop, while mass percentages higher than 3% result in increasing entropy as the random order of particle agglomeration found in higher concentration MAP dominates. Self-structured samples of different filler material and concentrations between 1 and 3 wt % have been investigated using X-ray tomography, where the emerging structures can be observed and visualized. The ring structures resulting from this research represent microinductivities which can be fabricated in a targeted manner, thus enabling new applications in the high-frequency radio field. Furthermore, these anisotropic, but well-organized, structures have magnetic field-dependent implications for optical, thermal, acoustic, and medical applications. KW - composites KW - ELASTOMERS KW - magnetism and magnetic properties KW - Particle KW - PERMEABILITY KW - self-assembly KW - sensors and actuators KW - VISCOELASTIC PROPERTIES KW - X-ray Y1 - 2019 U6 - https://doi.org/10.1002/app.48291 VL - 137 IS - 3 PB - Wiley ER - TY - CHAP A1 - Reindl, Andrea A1 - Meier, Hans A1 - Niemetz, Michael T1 - Software Framework for the Simulation of a Decentralized Battery Management System Consisting of Intelligent Battery Cells T2 - 2019 IEEE Student Conference on Research and Development (SCOReD), 15-17 Oct. 2019, Bandar Seri Iskandar, Malaysia N2 - Conventional battery management systems typically adopt hierarchical master-slave architectures. With regard to an uninterruptible power supply, the most significant disadvantage of central structures is the dependency of the errorfree function of the superior master board. The decentralized battery management system presented in this paper, consisting of consumers, generators and intelligent battery cells, is controlled without any central coordination authority. For this purpose, an intelligent control algorithm and a leader election algorithm are implemented on the microcontrollers of the battery cells. To test different control and election strategies, a software framework is presented for the complete simulation of the decentralized battery management system consisting of equal participants. KW - autonomous systems KW - Battery management system KW - decentralized control KW - distributed management KW - fault tolerant control KW - power system security KW - Renewable energy sources KW - uninterruptible power systems Y1 - 2019 U6 - https://doi.org/10.1109/SCORED.2019.8896284 SP - 75 EP - 80 ER - TY - CHAP A1 - Schiek, Roland A1 - Baronio, Fabio T1 - Spatial Akhmediev Breathers in Slab Waveguides T2 - 2019 Conference on Lasers and Electro-Optics Europe European Quantum Electronics Conference (CLEO/Europe-EQEC), 23-27 June 2019, Munich, Germany N2 - Summary form only given. The analytical breather-solutions of the Nonlinear Schrödinger Equation (NLS) [1] have been intensively studied and verified experimentally in the time-space system of optical pulse propagation in fibers [2]. In space-space systems, i.e. in optical beam propagation breathers in ultra-fast nonlinear media have not been observed due to the breather’s infinite background and a resulting extremely large power. In a lithium niobate slab waveguide with two second-harmonic (SH) resonances the resulting quasi-cubic cascaded quadratic nonlinearity provided together with the intrinsic cubic susceptibility enough nonlinearity for breather excitation at experimentally reachable powers. We could characterize the fi rst ultra -fast spatial -spatial optical breathers in a 5 -cm -long titanium indiffused lithium niobate slab waveguide at power levels down to tens of kW. The guided fundamental wave (FW) TM° fi lm mode at A = 1.32μm is phase -matched for type -I SH generation to TE 0 and TEi SH modes at temperatures near 295 and 344C. With temperature tuning the phase -mismatch and the two effective cascaded nonlinearities were adjusted. For breather observation, we aimed for a large phase -mismatch with low SH levels such that the cascaded nonlinearity is quasi -cubic and the propagation is well approximated by the NLS and its breather solutions. A frequency -doubled Nd:YAG-pumped OPA with CW-seeding delivered 5-ps long pulses with up to 200kW peak power in the waveguide. With a cylindrical telescope the beam was transformed into a very wide elliptical beam to approximate the breather background. The beam was end -fire coupled into the FW TM () mode. A variable few % of the beam were separated and coupled with a tilt and good overlap to the main beam into the waveguide to produce a spatial modulation of the input with adjustable period and modulation depth. A beam width of 1.5mm was large enough in the compromise between available beam power and infinite beam width. A beam with a transverse modulation with periods between 130 to 300μm approximates a constant background with modulation well enough to trigger modulation instability that develops eventually into the breather. KW - Frequency conversion KW - lithium niobate KW - Modulation KW - Optical beams KW - Optical pulses KW - Optical waveguides KW - Slabs Y1 - 2019 U6 - https://doi.org/10.1109/CLEOE-EQEC.2019.8872896 ER - TY - CHAP A1 - Hopkins, Andrew A1 - Hopfensperger, Bernhard A1 - Mellor, Phil T1 - DC-link Capacitor Reduction in Low Voltage and High Power Integrated Modular Motor Drives T2 - 2019 IEEE Energy Conversion Congress and Exposition (ECCE), 29 Sept.-3 Oct. 2019, Baltimore, MD, USA N2 - The development of 48V high power (>15 kW) automotive propulsion drives demands close integration of the power electronics and the electrical machine. Due to the large operating currents distributed multi-phase topologies are needed and physically separating the power converter from the e-machine would involve heavy cabling and costly connections. The volume and cost of the filter capacitor represents a major challenge in closely integrated high power integrated modular motor drives and techniques are needed to minimize this. The DC-link capacitor requires a large ripple current handling capability and cost, size and reliability limitations result in suitable candidate technologies being those with low volumetric energy densities. Use of interleaved multi three-phase machines are attractive due to the associated capacitor ripple current reduction. Discontinuous modulation schemes may also be employed as a technique for reducing the current ripple. In this paper techniques for capacitor ripple reduction are assessed through simulation and compared. KW - Capacitors KW - carrier phase shift KW - DC-link capacitor KW - dual 3-phase inverter KW - integrated modular motor drive KW - Interleaving KW - Inverters KW - Low voltage KW - Motor drives KW - Pulse width modulation KW - ripple current reduction KW - winding displacement KW - Windings Y1 - 2019 U6 - https://doi.org/10.1109/ECCE.2019.8913213 SP - 3208 EP - 3214 ER - TY - CHAP A1 - Scharfenberg, Georg A1 - Elis, Ludek A1 - Hofmann, Gerhard T1 - New Design Methodology – Using VHDL-AMS Models to Consider Aging Effects in Automotive Mechatronic Circuits for Safety Relevant Functions T2 - 2019 International Conference on Applied Electronics (AE), 10-11 Sept. 2019, Pilsen, Czech Republic N2 - In this paper a design method for mechatronic functions in an early design phase under consideration of the requirements of functional safety is proposed [14]. The goal of the method is to discover threats for the safety goals and to prove or optimize the diagnostic mechanisms. At the current design process a lifetime endurance test is performed in a late project phase. In order to avoid unexpected late design changes the method should be applied in an early design phase. The method is an additional way to avoid design failures for E/E functions with special focus on aging in the field of functional safety applications. The method is developed out of three standards VDI 2221 methodology for development and construction of technical systems and products [1]), VDI 2206 design methodology for mechatronic systems [2] and the ISO 26262 road vehicles - Functional Safety [3] by using the V-Model. Furthermore, a core element of the design method is simulating aging effects by applying VHDL - AMS. To demonstrate the design methodology a sensor out of the EGAS function is chosen as a safety relevant automotive system. The limitation is the availability of aging data for electrical components. KW - Aging KW - Design methodology KW - Functional Safety KW - Integrated circuit modeling KW - Mechatronic design method KW - Mechatronics KW - Resistor aging KW - safety Y1 - 2019 U6 - https://doi.org/10.23919/AE.2019.8867034 SP - 1 EP - 5 ER - TY - CHAP A1 - Brkic, Jovan A1 - Ceran, Muaz A1 - Elmoghazy, Mohamed A1 - Kavlak, Ramazan A1 - Haumer, Anton A1 - Kral, Christian T1 - Open Source PhotoVoltaics Library for Systemic Investigations T2 - Proceedings of the 13th International Modelica Conference, March 4-6, 2019, Regensburg, Germany N2 - For the planning of photovoltaic power plants standard software tools are used. Most of these software tools use statistical solar data to determine the overall energy harvest of a photovoltaic plant over one year. The calculations rely on stationary location and ideal boundary conditions, e.g., constant ambient temperature. Even though, for example, shadowing may be considered by standard software, the investigation of untypical configurations and problems cannot be performed by such software, as most configurations cannot be changed by the user. The presented PhotoVoltaics library was developed with the intention to provide a flexible framework for standard and non-standard problems. Particularly, the PhotoVoltaics library can be coupled with other Modelica libraries to perform systemic investigations. An application library, PhotoVoltaics_TGM, is provided as add-on, where measured data of two photovoltaic pants of the TGM in Vienna can be compared with simulation results. This add-on library serves as validation of the PhotoVoltaics library. KW - CELL KW - converter KW - data sheet KW - irradiance KW - maximum power tracking KW - module KW - Photovoltaics KW - plant KW - terrestrial solar model Y1 - 2019 U6 - https://doi.org/10.3384/ecp1915741 SP - 41 EP - 50 PB - Linköing University Electronic Press ER - TY - CHAP A1 - Alexander, Grimm A1 - Haumer, Anton T1 - Parametrization Of A Simplified Physical Battery Model T2 - Proceedings of the 13th International Modelica Conference, March 4-6, 2019, Regensburg, Germany N2 - The importance of batteries is increasing, especially in the field of the high power requirement systems like electric driven vehicles. Mobile energy storage makes it possible to accelerate with incredible torque, without any accruing air pollution. Due to the high costs of real components, it is of great use to simulate battery driven systems before building them. Transient processes within a cell are highly dependent on the operating point of the complete system, which makes it difficult to create equations and model arameterizations. This paper shows which data is important for cell modeling and how to parameterize simplified physical cell models. KW - battery parameterization KW - physical battery model KW - simplified battery model Y1 - 2019 U6 - https://doi.org/10.3384/ecp19157215 SP - 215 EP - 220 PB - Linköing University Electronic Press ER - TY - GEN A1 - Langer, Tobias T1 - Konzeption und Hardwareaufbau eines Dual-CAN (FD) Demonstrators mit Failure Injection Board und TFT-Touchdisplay N2 - Controller Area Network (CAN) ist in automatisierten Bereichen der Industrie ein wichtiger Bestandteil der Kommunikation vieler einzelner Komponenten. Spezielle Anwendungen fordern einen erhöhten Standard hinsichtlich Sicherheit und Fehlertoleranz. Eine Steigerung der Zuverlässigkeit des Systems ist somit numgänglich. Die vorliegende Arbeit befasst sich mit der Untersuchung eines Dual-CAN-Bussystems. Hierzu zählt die Entwicklung und Umsetzung eines Demonstratoraufbaus. Es werden fünf Nucleo STM32H7 Boards um ein sogenanntes Failure Injection Board (FIB) und ein 3,5" TFT-Touchdisplay erweitert sowie redundant miteinander über zwei speparate CAN verbunden. Mithilfe des FIBs wird das duale CAN-Netzwerk realisiert. Außerdem können die Abschlusswiderstände per Knopfdruck zugeschaltet und Drahtbrüche durch Relais auf dem redundanten CAN-Bus simuliert werden. Als weitere Anzeige- und Bedienmöglichkeit wird ein Touchdisplay auf das Nucleo STM32H7 Board gesteckt. Hier soll eine GUI eine intuitive Bedienung ermöglichen und den aktuellen Status der weiteren Teilnehmer im Netz anzeigen. Das FIB dient zur Entwicklung von Algorithmen um Fehler bzw. Drahtbrüche zu umgehen oder auch andere Busstrukturen zu untersuchen. KW - Controller Area Network KW - Labor für industrielle Elektronik KW - Zuverlässige Kommunikation Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-29852 ER - TY - JOUR A1 - Burdin, Dmitrii A. A1 - Chashin, Dmitri V. A1 - Ekonomov, Nikolai A. A1 - Fetisov, Leonid Y. A1 - Fetisov, Yuri K. A1 - Shamonin (Chamonine), Mikhail T1 - DC magnetic field sensing based on the nonlinear magnetoelectric effect in magnetic heterostructures JF - Journal of physics D: Applied physics N2 - Recently, highly sensitive magnetic field sensors using the magnetoelectric effect in composite ferromagnetic-piezoelectric layered structures have been demonstrated. However, most of the proposed concepts are not useful for measuring dc magnetic fields, because the conductivity of piezoelectric layers results in a strong decline of the sensor's sensitivity at low frequencies. In this paper, a novel functional principle of magnetoelectric sensors for dc magnetic field measurements is described. The sensor employs the nonlinear effect of voltage harmonic generation in a composite magnetoelectric structure under the simultaneous influence of a strong imposed ac magnetic field and a weak dc magnetic field to be measured. This physical effect arises due to the nonlinear dependence of the magnetostriction in the ferromagnetic layer on the magnetic field. A sensor prototype comprising of a piezoelectric fibre transducer sandwiched between two layers of the amorphous ferromagnetic Metglas (R) alloy was fabricated. The specifications regarding the magnetic field range, frequency characteristics, and noise level were studied experimentally. The prototype showed the responsivity of 2.5 V mT(-1) and permitted the measurement of dc magnetic fields in the range of similar to 10 nT to about 0.4 mT. Although sensor operation is based on the nonlinear effect, the sensor response can be made linear with respect to the measured magnetic field in a broad dynamic range extending over 5 orders of magnitude. The underlying physics is explained through a simplified theory for the proposed sensor. The functionality, differences and advantages of the magnetoelectric sensor compare well with fluxgate magnetometers. The ways to enhance the sensor performance are considered. KW - composite KW - magnetic field sensors KW - magnetic heterostructures KW - magnetoelectric effect KW - nonlinear magnetostriction KW - Sensors KW - voltage harmonic generation Y1 - 2016 U6 - https://doi.org/10.1088/0022-3727/49/37/375002 VL - 49 IS - 37 PB - IOP Publishing ER - TY - JOUR A1 - Baumer, Johannes A1 - Shamonin (Chamonine), Mikhail T1 - Abstandsensorsystem basierend auf dem Prinzip der optischen Reflektion für Anwendungen im Bereich Weiße Ware: Intensitätsreferenzierung und Linearisierung des Ausgnagssignals JF - TM - Technisches Messen N2 - Ein auf optischer Reflektion basierendes Abstandssensorsystem für die „Weiße Ware“ wird hier vorgestellt. Die technische Lösung greift auf ein allseits bekanntes Intensitätsreferenzierungsprinzip – die optische Brücke – zurück. Der Einfluss der Umgebungstemperatur kann kompensiert werden. Störeffekte wie alterungsbedingte Drift der optischen Elemente oder Systemvariationen der Empfindlichkeit verursacht durch die Streuung der einzelnen Komponenten können erfolgreich gehandhabt werden. Ein Algorithmus zur Ausgangslinearisierung und dessen Optimierung in Hinblick auf einen kostengünstigen Mikrokontroller wird beschrieben. Zum Schluss wird ein Prototyp eines Fertigungsautomaten, der zur Herstellung dieses Sensors dient, und dessen grundlegende Funktion vorgestellt. A reflective optical sensor system for distance measurements in white-goods applications is presented. The technical solution implements a well-known intensity referencing principle - the optical bridge - in a low-cost design. The influence of the ambient temperature can be compensated for. The spurious effects such as slow output drift caused by aging of optical components or the variation of the system sensitivity due to the parameter spreading of system components can be successfully overcome as well. An algorithm for linearizing the system response is described and optimized for a low-cost microcontroller. Finally, a prototype of an assembly line, which is used for producing this sensor system, is described and its basic funcionallity is demonstrated. T2 - Optical-reflection-based distance sensor system for white-goods applications: intensity referencing and response linearization KW - Fertigungskonzept KW - Kompensation von Störeffekten KW - Kostengünstiger Abstandssensor KW - Liearisierung der Sensorantwort KW - optische Reflektion Y1 - 2014 U6 - https://doi.org/10.1515/teme-2014-1014 VL - 81 IS - 2 SP - 62 EP - 69 PB - de Gruyter ER - TY - JOUR A1 - Stadler, Dominik A1 - Hofmann, Matthias J. A1 - Motschmann, Hubert A1 - Shamonin (Chamonine), Mikhail T1 - Automated system for measuring the surface dilational modulus of liquid-air interfaces JF - Measurement Science and Technology N2 - The surface dilational modulus is a crucial parameter for describing the rheological properties of aqueous surfactant solutions. These properties are important for many technological processes. The present paper describes a fully automated instrument based on the oscillating bubble technique. It works in the frequency range from 1 Hz to 500 Hz, where surfactant exchange dynamics governs the relaxation process. The originality of instrument design is the consistent combination of modern measurement technologies with advanced imaging and signal processing algorithms. Key steps on the way to reliable and precise measurements are the excitation of harmonic oscillation of the bubble, phase sensitive evaluation of the pressure response, adjustment and maintenance of the bubble shape to half sphere geometry for compensation of thermal drifts, contour tracing of the bubbles video images, removal of noise and artefacts within the image for improving the reliability of the measurement, and, in particular, a complex trigger scheme for the measurement of the oscillation amplitude, which may vary with frequency as a result of resonances. The corresponding automation and programming tasks are described in detail. Various programming strategies, such as the use of MATLAB (R) software and native C++ code are discussed. An advance in the measurement technique is demonstrated by a fully automated measurement. The instrument has the potential to mature into a standard technique in the fields of colloid and interface chemistry and provides a significant extension of the frequency range to established competing techniques and state-of-the-art devices based on the same measurement principle. KW - automated measurements KW - dilational modulus KW - graphical user interfaces KW - Image processing KW - oscillating bubble technique KW - signal processing KW - STABILITY KW - surface rheology Y1 - 2016 U6 - https://doi.org/10.1088/0957-0233/27/6/065301 VL - 27 IS - 6 PB - IOP PUBLISHING ER - TY - JOUR A1 - Schoepe, Wilfried A1 - Hänninen, Risto A1 - Niemetz, Michael T1 - Breakdown of Potential Flow to Turbulence Around a Sphere Oscillating in Superfluid 4He Above the Critical Velocity JF - Journal of low temperature physics N2 - The onset of turbulent flow around an oscillating sphere in superfluid 4He is known to occur at a critical velocity where is the circulation quantum and is the oscillation frequency. But it is also well known that initially in a first up-sweep of the oscillation amplitude, can be considerably exceeded before the transition occurs, thus leading to a strong hysteresis in the velocity sweeps. The velocity amplitude where the transition finally occurs is related to the density of the remanent vortices in the superfluid. Moreover, at temperatures below ca. 0.5 K and in a small interval of velocity amplitudes between and a velocity that is about 2 % larger, the flow pattern is found to be unstable, switching intermittently between potential flow and turbulence. From time series recorded at constant temperature and driving force, the distribution of the excess velocities is obtained and from that the failure rate. Below 0.1 K we also can determine the distribution of the lifetimes of the phases of potential flow. Finally, the frequency dependence of these results is discussed. KW - Intermittent switching KW - LAMINAR KW - MICROSPHERE KW - Oscillatory flow KW - Quantum turbulence KW - Remanent vorticity KW - VIBRATING-WIRE Y1 - 2015 U6 - https://doi.org/10.1007/s10909-014-1265-7 VL - 178 SP - 383 EP - 391 PB - Springer Nature ER - TY - JOUR A1 - Dechant, Eduard A1 - Fedulov, Feodor A1 - Chashin, Dmitri V. A1 - Fetisov, Leonid Y. A1 - Fetisov, Yuri K. A1 - Shamonin (Chamonine), Mikhail T1 - Low-frequency, broadband vibration energy harvester using coupled oscillators and frequency up-conversion by mechanical stoppers JF - Smart Materials and Structures N2 - The frequencies of ambient vibrations are often low (below 30 Hz). A broadband (3 dB bandwidth is larger than 10 Hz at an acceleration amplitude of 9.81 m s(-2)) vibration based energy harvester is proposed for transducing mechanical energy at such low frequencies into electrical energy. The mechanical setup converts low frequency mechanical vibrations into high frequency resonance oscillations of the transducer. This conversion is done by mechanical impacts on two mechanical stoppers. The originality of the presented design is that both low-frequency and high-frequency oscillators are permanently mechanically coupled. In the equivalent mechanical circuit, this coupling is achieved by connecting the ends of the stiff spring to both seismic masses, whereas one seismic mass (collison member) is also attached to the soft spring used as the constitutive element of a low-frequency oscillator. Further, both mechanical oscillators are not realized as conventional cantilever beams. In particular, the high frequency oscillator with the natural frequency of 340 Hz is a disc-shaped diaphragm with attached piezoelectric elements and a seismic mass. It is shown that it is possible to convert mechanical vibrations with acceleration amplitude of 9.81 m s(-2) in the region between approximately 7 and 25 Hz into electrical power larger than 0.1 mW with the maximum value of 0.8 mW. A simplified mathematical model based on piecewise linear coupled oscillators shows good agreement with experimental results. The ways to enhance the performance of the harvester and improve agreement with experiments are discussed. KW - broadband KW - efficiency KW - frequency up-conversion KW - low frequency KW - mechanical stoppers KW - Modeling KW - OUTPUT KW - Piezoelectric transducer KW - vibration energy harvesting Y1 - 2017 U6 - https://doi.org/10.1088/1361-665X/aa6e92 VL - 26 IS - 6 PB - IOP Publishing ER - TY - JOUR A1 - Setzpfandt, Frank A1 - Sohler, Wolfgang A1 - Schiek, Roland A1 - Pertsch, Thomas T1 - Nonlinear coupling in discrete optical waveguide arrays with quadratic nonlinearity JF - Physical Review A N2 - We demonstrate nonlinear coupling in a discrete optical system. This is achieved in waveguide arrays with quadratic nonlinearity, where the symmetries of the nonlinearly interacting waveguide modes are used to suppress the usually dominating nonlinear effects within individual waveguides. We derive a mathematical model to describe the nonlinear coupling in such waveguide arrays and show experimentally the profound effects of this nonlinear coupling mechanism on second-harmonic generation. KW - BLOCH OSCILLATIONS KW - DYNAMICS KW - LIQUID-CRYSTALS KW - PHOTONIC LATTICES KW - PROPAGATION KW - SOLITONS Y1 - 2015 U6 - https://doi.org/10.1103/PhysRevA.92.043832 VL - 92 IS - 4 PB - American Physical Society ER - TY - JOUR A1 - Niemetz, Michael A1 - Hänninen, Risto A1 - Schoepe, Wilfried T1 - On the Transition from Potential Flow to Turbulence Around a Microsphere Oscillating in Superfluid 4He JF - Journal of low temperature physics N2 - The flow of superfluid around a translationally oscillating sphere, levitating without mechanical support, can either be laminar or turbulent, depending on the velocity amplitude. Below a critical velocity that scales as and is temperature independent below 1 K, the flow is laminar (potential flow). Below 0.5 K, the linear drag force is caused by ballistic phonon scattering that vanishes as until background damping, measured in the empty cell, becomes dominant for K. Increasing the velocity amplitude above leads to a transition from potential flow to turbulence, where the large turbulent drag force varies as . In a small velocity interval % above , the flow is unstable below 0.5 K, switching intermittently between both patterns. From time series recorded at constant temperature and driving force, the lifetimes of both phases are analyzed statistically. We observe metastable states of potential flow which, after a mean lifetime of 25 min, ultimately break down due to vorticity created by natural background radioactivity. The lifetimes of the turbulent phases have an exponential distribution, and the mean increases exponentially with . We investigate the frequency at which the vortex rings are shed from the sphere. Our results are compared with recent data of other authors on vortex shedding by moving a laser beam through a Bose-Einstein condensate. Finally, we show that our observed transition to turbulence belongs to the class of "supertransient chaos" where lifetimes of the turbulent states increase faster than exponentially. KW - Bose-Einstein condensates KW - Critical velocity KW - DYNAMICS KW - EINSTEIN CONDENSED GAS KW - HE-4 KW - HELIUM KW - LAMINAR KW - MK TEMPERATURES KW - ONSET KW - Oscillatory flow KW - Quantum turbulence KW - Superfluid helium KW - Vortex shedding Y1 - 2017 U6 - https://doi.org/10.1007/s10909-017-1745-7 VL - 187 IS - 3-4 SP - 195 EP - 220 PB - Springer Nature ER - TY - JOUR A1 - Monkman, Gareth J. A1 - Sindersberger, Dirk A1 - Diermeier, Andreas A1 - Prem, Nina T1 - The magnetoactive electret JF - smart materials and structures N2 - A magnet which adheres to every surface, not only those of ferromagnetic materials, has hitherto been the domain of science fiction. Now for the first time such a novel device exists. The fusion of a permanently magnetized magnetoactive polymer containing hard magnetic particles and an electret enhanced with ferroelectric particles has resulted in the development of a new smart device-the magnetoactive electret. Magnetoactive electrets can be made to exhibit the usual magnetic properties of permanent magnetism together with the electrostatic properties of electrets. This results in simultaneous magnetoadhesion and electroadhesion forces from the same elastomeric element. The biasing field, needed to avoid discontinuities concerned with transition through the zero point in operating curves, is normally provided by means of either a magnetic or an electric field. This novel technology provides both bias options in a single device. KW - 6D printing KW - electret KW - electroadhesion KW - FLUIDS KW - MAGNETIC-FIELD KW - magnetoactive electret KW - magnetoactive polymer KW - magnetoadhesion KW - Magnetorheological elastomers KW - RHEOLOGY Y1 - 2017 U6 - https://doi.org/10.1088/1361-665X/aa738f VL - 26 IS - 7 PB - IOP Publishing ER - TY - JOUR A1 - Setzpfandt, Frank A1 - Solntsev, Alexander S. A1 - Titchener, James A1 - Wu, Che Wen A1 - Xiong, Chunle A1 - Schiek, Roland A1 - Pertsch, Thomas A1 - Neshev, Dragomir N. A1 - Sukhorukov, Andrey A. T1 - Tunable generation of entangled photons in a nonlinear directional coupler JF - Laser & Photonics Reviews N2 - The on-chip integration of quantum light sources has enabled the realization of complex quantum photonic circuits. However, for the practical implementation of such circuits in quantum information applications, it is crucial to develop sources delivering entangled quantum photon states with on-demand tunability. Here we propose and experimentally demonstrate the concept of a widely tunable quantum light source based on spontaneous parametric down-conversion in a simple nonlinear directional coupler. We show that spatial photon-pair correlations and entanglement can be reconfigured on-demand by tuning the phase difference between the pump beams and the phase mismatch inside the structure. We experimentally demonstrate the generation of split states, robust N00N states, various intermediate regimes and biphoton steering on a single chip. Furthermore we theoretically investigate other regimes allowing all-optically tunable generation of all Bell states and flexible control of path-energy entanglement. Such wide-range capabilities of a structure comprised of just two coupled nonlinear waveguides are attributed to the intricate interplay between linear coupling and nonlinear phase matching. This scheme provides an important advance towards the realization of reconfigurable quantum circuitry. KW - ARRAYS KW - directional coupler KW - entanglement KW - GATES KW - nonlinearity KW - PAIR GENERATION KW - photon pairs KW - WAVE KW - waveguides Y1 - 2016 U6 - https://doi.org/10.1002/lpor.201500216 VL - 10 IS - 1 SP - 131 EP - 136 PB - WILEY-VCH ER - TY - JOUR A1 - Rösel, Birgit T1 - Just-in-Time Teaching für einen Grundkurs Regelungstechnik – Ergebnisse und Auswirkungen der Profistufe des Zertifikats Hochschullehre JF - Didaktiknachrichten Y1 - 2018 UR - https://diz-bayern.de/DiNa/06_2018 IS - 06 SP - 66 EP - 71 PB - Zentrum für Hochschuldidaktik (DiZ) ER - TY - RPRT A1 - Emmert, Michael A1 - Glück, Sven A1 - Freilinger, Eva A1 - Brandl, Dominik A1 - Schindler, Sebastian A1 - Kaul, Nicolas A1 - Rasp, Franziska A1 - Akstaller, Monika A1 - Wetzel, Daniel A1 - Jupke, Michael A1 - Bodensteiner, Michael A1 - Hohlfeld, Philipp A1 - Böhm, Kevin A1 - Brem, Theresa A1 - Hammer, Pascal A1 - Singer, Thomas A1 - Karing, Maria A1 - Schneider, Viola A1 - Ostermeier, Tobias ED - Meier, Hans ED - Niemetz, Michael ED - Reindl, Andrea T1 - FMS-Berichte (Mai 2021) BT - Seminar zu aktuellen Themen der Elektro- und Informationstechnik N2 - Dieser Bericht entstand auf Initiative der Studierenden des 2020 neu gegründeten Masterstudiengangs „Elektro- und Informationstechnik (MEI)“, die an der Pflichtlehrveranstaltung „Forschungsmethoden und Seminar (FMS)“ im Wintersemester 2020/21 teilnahmen. Diese Lehrveranstaltung hat das Ziel, systematisch an das wissenschaftliche Arbeiten, speziell die Wissenschaftskommunikation, heranzuführen. Daher war geeignete Literatur zu einem individuellen Thema zu recherchieren, Veröffentlichungen auf ihre Relevanz hin zu beurteilen und letztendlich eine eigene Ausarbeitung basierend auf der Literaturrecherche zu erarbeiten und diese in einem Vortrag zu präsentieren. Parallel dazu erfolgte im Theorieteil die entsprechende Hinführung zu den verschiedenen Elementen der Wissenschaftskommunikation: • Bedeutung der Wissenschaftskommunikation für die Arbeit der Ingenieure in Forschung und Entwicklung • Literaturrecherche, Suchmaschinen, Sichtung und Analyse vorhandener Publikationen, Bewertung der Qualität aufgefundener Fachliteratur, Auswahl geeigneter Materialien für die eigene Arbeit • Aufbereitung und Darstellung der recherchierten technischer Inhalte in Form einer seitenanzahlbegrenzten wissenschaftlichen Ausarbeitung • Einhalten formaler Randbedingungen bzgl. Strukturierung, einschl. Bildnachweise und Zitationsstile • Peer-review-Prozess bei wertschätzender Beurteilung der Leistung anderer • Publikumsangepasstes Aufbereiten komplexer fachlicher Inhalte mit hochschulöffentlicher Präsentation der Ergebnisse • Führen mündlicher wissenschaftlicher Diskurse Nachdem die Masterstudierenden in der Regel über noch keine eigene wissenschaftliche Forschungserfahrung bzw. -inhalte verfügen, lag der wählbare Schwerpunkt der Literatursuche auf der Bearbeitung von vorgegeben aktuellen technischen oder gesellschaftspolitischen Forschungsthemen. Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-19155 CY - Regensburg ER - TY - CHAP A1 - Büttner, Johannes A1 - Bohigas Boladeras, Pere A1 - Gottschalk, Philipp A1 - Kucera, Markus A1 - Waas, Thomas T1 - Performance Isolation of Co-located Workload in a Container-based Architecture for Automobile T2 - 9th International Conference on Ambient Computing, Applications, Services and Technologies 2019, 22-26.09.2019, Porto, Portugal N2 - As the development in the automotive sector is facing upcoming challenges, the demand for in-vehicle computing power capacity increases and the need for flexible hardware and software structures arises, allowing dynamic managament of resources. In this new scenario, software components are to be added, removed, updated and migrated between computing units. To isolate the software components from each other and allow its orchestration, a container-based virtualization approach is being tested throughout this research. The analysis focuses on the question if this virtualization technology could be an option to ensure an interference-free operation. Four different sample applications from the automotive environment are tested for their susceptibility to resource contention. The research on the one hand shows that CPU and memory used by an application can be largely isolated with this technology, but on the other hand, it becomes apparent that support for I/O-heavy usage is currently not implemented sufficiently for container engines. KW - container-based virtualization KW - resource management KW - resource isolation KW - stress testing Y1 - 2019 UR - https://ns2.thinkmind.org/articles/ambient_2019_2_20_40020.pdf SN - 978-1-61208-739-9 SP - 31 EP - 37 ER - TY - RPRT A1 - Marterer, Verena A1 - Kemeter, Dominik A1 - Lang, Andreas A1 - Dischner, Alexander A1 - Huber, Stephanie A1 - Obermeier, Maximilian A1 - Langer, Tobias ED - Meier, Hans ED - Niemetz, Michael ED - Reindl, Andrea T1 - FMS-Berichte Sommersemester 2021 BT - Seminar zu aktuellen Themen der Elektro- und Informationstechnik N2 - Dieser Bericht entstand auf Initiative der Studierenden des 2020 neu gegründeten Masterstudiengangs „Elektro- und Informationstechnik (MEI)“, die an der Pflichtlehrveranstaltung „Forschungsmethoden und Seminar (FMS)“ im Sommersemester 2021 teilnahmen. Diese Lehrveranstaltung hat das Ziel, systematisch an das wissenschaftliche Arbeiten, speziell die Wissenschaftskommunikation, heranzuführen. Daher war geeignete Literatur zu einem individuellen Thema zu recherchieren, Veröffentlichungen auf ihre Relevanz hin zu beurteilen und letztendlich eine eigene Ausarbeitung basierend auf der Literaturrecherche zu erarbeiten und diese in einem Vortrag zu präsentieren. Parallel dazu erfolgte im Theorieteil die entsprechende Hinführung zu den verschiedenen Elementen der Wissenschaftskommunikation: • Bedeutung der Wissenschaftskommunikation für die Arbeit der Ingenieure in Forschung und Entwicklung • Literaturrecherche, Suchmaschinen, Sichtung und Analyse vorhandener Publikationen, Bewertung der Qualität aufgefundener Fachliteratur, Auswahl geeigneter Materialien für die eigene Arbeit • Aufbereitung und Darstellung der recherchierten technischer Inhalte in Form einer seitenanzahlbegrenzten wissenschaftlichen Ausarbeitung • Einhalten formaler Randbedingungen bzgl. Strukturierung, einschl. Bildnachweise und Zitationsstile • Peer-review-Prozess bei wertschätzender Beurteilung der Leistung anderer • Publikumsangepasstes Aufbereiten komplexer fachlicher Inhalte mit hochschulöffentlicher Präsentation der Ergebnisse • Führen mündlicher wissenschaftlicher Diskurse Nachdem die Masterstudierenden in der Regel über noch keine eigene wissenschaftliche Forschungserfahrung bzw. -inhalte verfügen, lag der wählbare Schwerpunkt der Literatursuche auf der Bearbeitung von vorgegeben aktuellen technischen oder gesellschaftspolitischen Forschungsthemen. KW - Elektrotechnik KW - Informationstechnik KW - Angewandte Wissenschaften KW - Literaturrecherche KW - Literature Review KW - Applied Sciences KW - Electrical engineering KW - Information technology Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-21040 CY - Regensburg ER - TY - GEN ED - Monkman, Gareth J. T1 - Soft robotics Y1 - 2022 SN - 978-981-5051-72-8 SN - 9789815051735 U6 - https://doi.org/10.2174/97898150517281220101 PB - Bentham Science CY - Singapore ER - TY - GEN A1 - Schiek, Roland T1 - On the experimental ex citation of modulation instability and Akhmediev breathers T2 - CHAOS 2020, Proceedings, 13th Chaotic Modeling and Simulation, International Conference, 9 - 12 June, 2020, Florence, Italy, Y1 - 2020 ER - TY - CHAP A1 - Eberhart, Philip A1 - Chung, Tek Shan A1 - Haumer, Anton A1 - Kral, Christian T1 - Open Source Library for the Simulation of Wind Power Plants T2 - Proceedings of the 11th International Modelica Conference, Versailles, France, September 21-23, 2015 N2 - This paper presents the new open source Modelica libraryWindPowerPlants. For the economic assessment of either a wind power plant or an entire wind park, the accurate prediction of the energy output is essential. Such prediction is usually performed by means of calculations based on statistical wind data. The proposed WindPowerPlants library is capable of assessing the energy output both for statistical and real wind data based on time domain simulations. In the presented version of the library wind turbine models are modeled with pitch control. The generator models have variable speed and an optional connector to the mains. The entire library is based on power balance conditions and losses are fully neglected. Yet, the library can be extended towards more detailed models considering different types of losses. The structure and components of the library are presented. Simulations examples are shown and compared with reference data. The applicability of the proposed WindPowerPlants library is demonstrated and possible enhancements are discussed. KW - variable speed KW - pitch control KW - Wind power pants KW - energy KW - statistical wind data KW - power Y1 - 2015 U6 - https://doi.org/10.3384/ecp15118929 SP - 929 EP - 936 CY - Linköping ER - TY - JOUR A1 - Maas, Roland A1 - Huemmer, Christian A1 - Sehr, Armin A1 - Kellermann, Walter T1 - A Bayesian view on acoustic model-based techniques for robust speech recognition JF - EURASIP Journal on Advances in Signal Processing N2 - This article provides a unifying Bayesian view on various approaches for acoustic model adaptation, missing feature, and uncertainty decoding that are well-known in the literature of robust automatic speech recognition. The representatives of these classes can often be deduced from a Bayesian network that extends the conventional hidden Markov models used in speech recognition. These extensions, in turn, can in many cases be motivated from an underlying observation model that relates clean and distorted feature vectors. By identifying and converting the observation models into a Bayesian network representation, we formulate the corresponding compensation rules. We thus summarize the various approaches as approximations or modifications of the same Bayesian decoding rule leading to a unified view on known derivations as well as to new formulations for certain approaches. KW - APPROXIMATION KW - Bayesian network KW - CLASSIFICATION KW - COMPENSATION KW - FEATURE ENHANCEMENT KW - HMM ADAPTATION KW - LINEAR-REGRESSION KW - Missing feature KW - Model adaptation KW - PREDICTION KW - Reverberation KW - Robust automatic speech recognition KW - SUM KW - Uncertainty decoding Y1 - 2015 U6 - https://doi.org/10.1186/s13634-015-0287-x VL - 103 PB - Springer Nature ER - TY - JOUR A1 - Kurzweil, Peter A1 - Scheuerpflug, Wolfgang T1 - State-of-charge monitoring and battery diagnosis of different lithium ion chemistries using impedance spectroscopy JF - Batteries N2 - For lithium iron phosphate batteries (LFP) in aerospace applications, impedance spectroscopy is applicable in the flat region of the voltage-charge curve. The frequency-dependent pseudocapacitance at 0.15 Hz is presented as useful state-of-charge (SOC) and state-of-health (SOH) indicator. For the same battery type, the prediction error of pseudocapacitance is better than 1% for a quadratic calibration curve, and less than 36% for a linear model. An approximately linear correlation between pseudocapacitance and Ah battery capacity is observed as long as overcharge and deep discharge are avoided. We verify the impedance method in comparison to the classical constant-current discharge measurements. In the case of five examined lithium-ion chemistries, the linear trend of impedance and SOC is lost if the slope of the discharge voltage curve versus SOC changes. With nickel manganese cobalt (NMC), high impedance modulus correlates with high SOC above 70%. KW - battery life testing KW - capacitance KW - lithium-ion battery KW - state-of-charge determination KW - state-of-health KW - pseudocharge KW - impedance spectroscopy KW - aging Y1 - 2021 U6 - https://doi.org/10.3390/batteries7010017 VL - 7 IS - 1 ER - TY - JOUR A1 - Räsänen, Esa A1 - Pulkkinen, Otto A1 - Virtanen, Tuomas A1 - Zollner, Manfred A1 - Hennig, Holger T1 - Fluctuations of hi-hat timing and dynamics in a virtuoso drum track of a popular music recording JF - PLoS ONE N2 - Long-range correlated temporal fluctuations in the beats of musical rhythms are an inevitable consequence of human action. According to recent studies, such fluctuations also lead to a favored listening experience. The scaling laws of amplitude variations in rhythms, however, are widely unknown. Here we use highly sensitive onset detection and time series analysis to study the amplitude and temporal fluctuations of Jeff Porcaro's one-handed hi-hat pattern in "I Keep Forgettin'"-one of the most renowned 16th note patterns in modern drumming. We show that fluctuations of hi-hat amplitudes and interbeat intervals (times between hits) have clear long-range correlations and short-range anticorrelations separated by a characteristic time scale. In addition, we detect subtle features in Porcaro's drumming such as small drifts in the 16th note pulse and non-trivial periodic two-bar patterns in both hi-hat amplitudes and intervals. Through this investigation we introduce a step towards statistical studies of the 20th and 21st century music recordings in the framework of complex systems. Our analysis has direct applications to the development of drum machines and to drumming pedagogy. KW - Humans KW - Models, Theoretical KW - Music Y1 - 2015 U6 - https://doi.org/10.1371/journal.pone.0127902 VL - 10 IS - 6 PB - PLOS ER - TY - JOUR A1 - Romeis, Dirk A1 - Kostrov, Sergei A. A1 - Kramarenko, Elena Yu A1 - Stepanov, Gennady V. A1 - Shamonin (Chamonine), Mikhail A1 - Saphiannikova, M. T1 - Magnetic-field-induced stress in confined magnetoactive elastomers JF - Soft Matter N2 - We present a theoretical approach for calculating the state of stress induced by a uniform magnetic field in confined magnetoactive elastomers of arbitrary shape. The theory explicitly includes the magnetic field generated by magnetizable spherical inclusions in the sample interior assuming a non-linear magnetization behavior. The initial spatial distribution of particles and its change in an external magnetic field are considered. This is achieved by the introduction of an effective demagnetizing factor where both the sample shape and the material microstructure are taken into account. Theoretical predictions are fitted to the stress data measured using a specifically designed experimental setup. It is shown that the theory enables the quantification of the effect of material microstructure upon introducing a specific microstructural factor and its derivative with respect to the extensional strain in the undeformed state. The experimentally observed differences between isotropic and anisotropic samples, compliant and stiff elastomer matrices are explained. Y1 - 2020 U6 - https://doi.org/10.1039/D0SM01337D VL - 16 IS - 39 SP - 9047 EP - 9058 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Belyaeva, Inna A. A1 - Kramarenko, Elena Yu A1 - Stepanov, Gennady V. A1 - Sorokin, Vladislav V. A1 - Stadler, Dominik A1 - Shamonin (Chamonine), Mikhail T1 - Transient magnetorheological response of magnetoactive elastomers to step and pyramid excitations JF - SOFT MATTER N2 - Transient rheological response of magnetoactive elastomers is experimentally studied using dynamic torsion at a fixed oscillation frequency in temporally stepwise changing magnetic fields and oscillation amplitudes. For step magnetic-field excitations, at least three exponential functions are required to reasonably describe the time behavior of the storage shear modulus over long time scales (>10(3) s). The deduced characteristic time constants of the corresponding rearrangement processes of the filler network differ approximately by one order of magnitude: tau(1) less than or similar to 10(1) s, tau(2) similar to 10(2) s, and tau(3) similar to 10(3) s. The sudden imposition of the external magnetic field activates a very fast rearrangement process with the characteristic time under 10 s, which cannot be determined more precisely due to the measurement conditions. Even more peculiar transient behavior has been observed during pyramid excitations, when either the external magnetic field was first stepwise increased and then decreased in a staircase manner at a fixed strain amplitude gamma or the strain amplitude gamma was first stepwise increased and then decreased in a staircase manner at a fixed magnetic field. In particular, the so-called "cross-over effect'' has been identified in both dynamical loading programs. This cross-over effect seems to be promoted by the application of the external magnetic field. The experimental results are discussed in the context of the specific rearrangement of the magnetic filler network under the simultaneous action of the external magnetic field and shear deformation. Striking similarities of the observed phenomena to the structural relaxation processes in glassy materials and to the jamming transition of granular materials are pointed out. The obtained results are important for fundamental understanding of material behavior in magnetic fields as well as for the development of devices on the basis of magnetoactive elastomeric materials. KW - AMPLITUDE KW - BEHAVIOR KW - DEPENDENCE KW - FLUID KW - HOMOGENEOUS MAGNETIC-FIELD KW - NORMAL FORCE KW - OSCILLATORY SHEAR KW - TIME KW - VISCOELASTIC PROPERTIES Y1 - 2016 U6 - https://doi.org/10.1039/c5sm02690c VL - 12 IS - 11 SP - 2901 EP - 2913 PB - ROYAL SOC CHEMISTRY ER - TY - JOUR A1 - Belyaeva, Inna A. A1 - Kramarenko, Elena Yu A1 - Shamonin (Chamonine), Mikhail T1 - Magnetodielectric effect in magnetoactive elastomers: Transient response and hysteresis JF - POLYMER N2 - Magnetodielectric properties of magnetoactive elastomers comprising micrometer-sized iron particles dispersed in compliant elastomer matrices are experimentally studied in stepwise time-varying dc magnetic fields. It is found that imposition of magnetic field significantly increases both the effective lossless permittivity of these composite materials as well as their effective conductivity. These magnetodielectric effects are more pronounced for larger concentrations of soft-magnetic filler particles and softer elastomer matrices. The largest observed relative change of the effective dielectric constant in the maximum magnetic field of 0.57 T is of the order of 1000%. The largest observed absolute change of the loss tangent is approximately 0.8. The transient response of the magnetodielectric effect to a step magnetic-field excitation can be rather complex. It changes from a simple monotonic growth with time for small magnetic-field steps (<0.1 T) to a non-monotonic behavior with a significant rapidly appearing overshoot for large magnetic-field steps (>0.3 T). The settling time to the magnetic-field step excitation can reach roughly 1000 s and it depends on the applied magnetic field and sample composition. There is also significant hysteresis of the magnetodielectric effect on the externally applied magnetic field. These findings are attributed to the rearrangement of ferromagnetic filler particles in external magnetic fields. The results will be useful for understanding and predicting the transient behavior of magnetoactive elastomers in applications where the control magnetic field is time dependent. (C) 2017 Elsevier Ltd. All rights reserved. KW - BEHAVIOR KW - composites KW - DIELECTRIC-PROPERTIES KW - hysteresis KW - MAGNETIC-FIELD KW - magnetoactive elastomer KW - magnetodielectric effect KW - Magnetorhelogical elastomer KW - MELT STATE KW - MICROSTRUCTURE KW - POLYMER DEGRADATION KW - PROGRESS KW - Smart material KW - THERMOOXIDATIVE DEGRADATION KW - TIME-RESOLVED RHEOLOGY KW - Transient response Y1 - 2017 U6 - https://doi.org/10.1016/j.polymer.2017.08.056 VL - 127 SP - 119 EP - 128 PB - ELSEVIER ER - TY - JOUR A1 - Sorokin, Vladislav V. A1 - Belyaeva, Inna A. A1 - Shamonin (Chamonine), Mikhail A1 - Kramarenko, Elena Yu T1 - Magnetorheological response of highly filled magnetoactive elastomers from perspective of mechanical energy density: Fractal aggregates above the nanometer scale? JF - Physical Review E N2 - The dynamic shear modulus of magnetoactive elastomers containing 70 and 80 mass % of carbonyl iron microparticles is measured as a function of strain amplitude via dynamic torsion oscillations in various magnetic fields. The results are presented in terms of the mechanical energy density and considered in the framework of the conventional Kraus model. The form exponent of the Kraus model is further related to a physical model of Huber et al. [Huber et al., J. Phys.: Condens. Matter 8, 409 (1996)] that uses a realistic representation for the cluster network possessing fractal structure. Two mechanical loading regimes are identified. At small strain amplitudes the exponent beta of the Kraus model changes in an externally applied magnetic field due to rearrangement of ferromagnetic-filler particles, while at large strain amplitudes, the exponent beta seems to be independent of the magnetic field. The critical mechanical energy characterizing the transition between these two regimes grows with the increasing magnetic field. Similarities between agglomeration and deagglomeration of magnetic filler under simultaneously applied magnetic field and mechanical shear and the concept of jamming transition are discussed. It is proposed that the magnetic field should be considered as an additional parameter to the jamming phase diagram of rubbers filled with magnetic particles. KW - BEHAVIOR KW - composites KW - hysteresis KW - MAGNETIC-FIELD KW - MODEL KW - RHEOLOGY KW - RUBBER KW - SENSITIVE ELASTOMERS KW - VISCOELASTIC PROPERTIES Y1 - 2017 U6 - https://doi.org/10.1103/PhysRevE.95.062501 VL - 95 IS - 6 PB - Amer Physical Soc ER - TY - CHAP A1 - Shamonin (Chamonine), Mikhail A1 - Kramarenko, Elena Yu ED - Domracheva, Natalia ED - Caporali, Maria ED - Rentschler, Eva T1 - Highly Responsive Magnetoactive Elastomers (Chapter 7) T2 - Novel Magnetic Nanostructures N2 - This chapter introduces composite smart materials known as magnetoactive (MAEs) or magnetorheological elastomers. It starts by defining these materials and distinguishing them from relevant magnetorheological fluids and ferrofluids. It then gives the overview of constitutive materials for the polymer matrix and filler particles. Next, the influence of external magnetic field on physical properties of MAEs is discussed. The emphasis is made on mechanical properties, which are the most important for real-world applications. In particular, magnetomechanical effects such as magnetostriction, magnetodeformation, and magnetorheological effect are discussed. The magnetic Payne effect is presented as an example of a nonlinear behavior. Electromagnetic and acoustic properties are also considered. The chapter finishes with the brief discussion of the future prospects in research and development of MAEs. Y1 - 2018 SN - 9780128135945 U6 - https://doi.org/10.1016/B978-0-12-813594-5.00007-2 SP - 221 EP - 245 PB - Elsevier ER - TY - JOUR A1 - Diermeier, Andreas A1 - Sindersberger, Dirk A1 - Angele, Peter A1 - Kujat, Richard A1 - Monkman, Gareth J. T1 - Sensor system for use with low intensity pulsed ultrasound JF - Sensor review N2 - Purpose Ultrasound is a well-established technology in medical science, though many of the conventional measurement systems (hydrophones and radiation force balances [RFBs]) often lack accuracy and tend to be expensive. This is a significant problem where sensors must be considered to be "disposable" because they inevitably come into contact with biological fluids and expense increases dramatically in cases where a large number of sensors in array form are required. This is inevitably the case where ultrasound is to be used for the in vitro growth stimulation of a large plurality of biological samples in tissue engineering. Traditionally only a single excitation frequency is used (typically 1.5 MHz), but future research demands a larger choice of wavelengths for which a single broadband measurement transducer is desirable. Furthermore, because of implementation conditions there can also be large discrepancies between measurements. The purpose of this paper deals with a very cost-effective alternative to expensive RFBs and hydrophones. Design/methodology/approach Utilization of cost-effective piezoelectric elements as broadband sensors. Findings Very effective results with equivalent (if not better) accuracy than expensive alternatives. Originality/value This paper concentrates on how very cost-effective piezoelectric ultrasound transducers can be implemented as sensors for ultrasound power measurements with accuracy as good, if not better than those achievable using radiation force balances or hydrophones. KW - BALANCE KW - Hydrophone KW - Mesenchymal stem cell KW - Piezoelectric transducer KW - Radiation force balance KW - Sensors KW - therapy KW - Tissue engineering KW - Ultrasound Y1 - 2019 U6 - https://doi.org/10.1108/SR-11-2018-0304 SN - 0260-2288 VL - 39 IS - 6 SP - 828 EP - 834 PB - Emerald ER - TY - JOUR A1 - Burdin, Dmitrii A. A1 - Ekonomov, Nikolai A. A1 - Chashin, Dmitri V. A1 - Fetisov, Leonid Y. A1 - Fetisov, Yuri K. A1 - Shamonin (Chamonine), Mikhail T1 - Temperature Dependence of the Resonant Magnetoelectric Effect in Layered Heterostructures JF - Materials N2 - The dependence of the resonant direct magnetoelectric effect on temperature is studied experimentally in planar composite structures. Samples of rectangular shapes with dimensions of 5 mm x 20 mm employed ferromagnetic layers of either an amorphous (metallic glass) alloy or nickel with a thickness of 20-200 m and piezoelectric layers of single crystalline langatate material or lead zirconate titanate piezoelectric ceramics with a thickness of 500 m. The temperature of the samples was varied in a range between 120 and 390 K by blowing a gaseous nitrogen stream around them. It is shown that the effective characteristics of the magnetoelectric effectsuch as the mechanical resonance frequency f(r), the quality factor Q and the magnitude of the magnetoelectric coefficient (E) at the resonance frequencyare contingent on temperature. The interrelations between the temperature changes of the characteristics of the magnetoelectric effect and the temperature variations of the following material parametersYoung's modulus Y, the acoustic quality factor of individual layers, the dielectric constant epsilon, the piezoelectric modulus d of the piezoelectric layer as well as the piezomagnetic coefficients ((n)) of the ferromagnetic layerare established. The effect of temperature on the characteristics of the nonlinear magnetoelectric effect is observed for the first time. The results can be useful for designing magnetoelectric heterostructures with specified temperature characteristics, in particular, for the development of thermally stabilized magnetoelectric devices. KW - acoustic quality factor KW - composite structure KW - linear KW - magnetoelectric effect KW - magnetoelectric heterostructure KW - magnetostriction KW - nonlinear KW - piezoelectric KW - temperature dependence Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-32185 N1 - corresponding author: Mikhail Shamonin VL - 10 IS - 10 PB - MDPI ER - TY - JOUR A1 - Dechant, Eduard A1 - Fedulov, Feodor A1 - Fetisov, Leonid Y. A1 - Shamonin (Chamonine), Mikhail T1 - Bandwidth Widening of Piezoelectric Cantilever Beam Arrays by Mass-Tip Tuning for Low-Frequency Vibration Energy Harvesting JF - Applied Science N2 - Wireless sensor networks usually rely on internal permanent or rechargeable batteries as a power supply, causing high maintenance efforts. An alternative solution is to supply the entire system by harvesting the ambient energy, for example, by transducing ambient vibrations into electric energy by virtue of the piezoelectric effect. The purpose of this paper is to present a simple engineering approach for the bandwidth optimization of vibration energy harvesting systems comprising multiple piezoelectric cantilevers (PECs). The frequency tuning of a particular cantilever is achieved by changing the tip mass. It is shown that the bandwidth enhancement by mass tuning is limited and requires several PECs with close resonance frequencies. At a fixed frequency detuning between subsequent PECs, the achievable bandwidth shows a saturation behavior as a function of the number of cantilevers used. Since the resonance frequency of each PEC is different, the output voltages at a particular excitation frequency have different amplitudes and phases. A simple power-transfer circuit where several PECs with an individual full wave bridge rectifier are connected in parallel allows one to extract the electrical power close to the theoretical maximum excluding the diode losses. The experiments performed on two- and three-PEC arrays show reasonable agreement with simulations and demonstrate that this power-transfer circuit additionally influences the frequency dependence of the harvested electrical power. KW - array KW - BAND-PASS FILTERS KW - bandwidth KW - BIMORPH KW - Optimization KW - OUTPUT KW - PERFORMANCE KW - piezoelectric cantilever KW - POWER KW - vibration energy harvesting Y1 - 2017 U6 - https://doi.org/10.3390/app7121324 N1 - Corresponding Author: Mikhail Shamonin VL - 7 IS - 12 PB - MDPI ER - TY - JOUR A1 - Nadzharyan, Timur A. A1 - Shamonin (Chamonine), Mikhail A1 - Kramarenko, Elena Yu T1 - Theoretical Modeling of Magnetoactive Elastomers on Different Scales: A State-of-the-Art Review JF - Polymers N2 - A review of the latest theoretical advances in the description of magnetomechanical effects and phenomena observed in magnetoactive elastomers (MAEs), i.e., polymer networks filled with magnetic micro- and/or nanoparticles, under the action of external magnetic fields is presented. Theoretical modeling of magnetomechanical coupling is considered on various spatial scales: from the behavior of individual magnetic particles constrained in an elastic medium to the mechanical properties of an MAE sample as a whole. It is demonstrated how theoretical models enable qualitative and quantitative interpretation of experimental results. The limitations and challenges of current approaches are discussed and some information about the most promising lines of research in this area is provided. The review is aimed at specialists involved in the study of not only the magnetomechanical properties of MAEs, but also a wide range of other physical phenomena occurring in magnetic polymer composites in external magnetic fields. KW - magnetodeformation KW - magnetorheological effect KW - mechanical properties KW - magnetic particles KW - theoretical modeling KW - magnetorheological elastomersn KW - magnetoactive elastomers Y1 - 2022 U6 - https://doi.org/10.3390/polym14194096 VL - 14 IS - 19 SP - 1 EP - 42 PB - MDPI ER - TY - JOUR A1 - Snarskii, Andrei A. A1 - Podlasov, Sergii A1 - Shamonin (Chamonine), Mikhail T1 - Isotropic inertia tensor without symmetry of mass distribution JF - American Journal of Physics N2 - Conventional calculations of the inertia tensor in undergraduate physics course are usually done for highly symmetrical bodies. Students might therefore get the impression that the moment of inertia about any axis through the center of mass is the same only for bodies with the highest degree of symmetry relative to this point, e.g., for spheres. A simple, seemingly counterintuitive example is presented, showing that the moment of inertia of a non-regular body, here an assembly of material points, can be the same about any axis passing through its center of mass. Y1 - 2021 U6 - https://doi.org/10.1119/10.0005416 VL - 89 IS - 10 SP - 916 EP - 920 PB - AIP Publishing ER - TY - CHAP A1 - Schiek, Roland A1 - Setzpfandt, Frank A1 - Pertsch, Thomas A1 - Baronio, Fabio A1 - de Angelis, Costantino T1 - Spatial Rogue Waves in Quadratic Optical Slab Waveguides T2 - Advanced Photonics 2018 (BGPP, IPR, NP, NOMA, Sensors, Networks, SPPCom, SOF), OSA Techncail Digest (online) (Optica Publishing Group, 2018), paper NpTh1H.7 N2 - Spatial optical breather solutions of the Nonlinear Schrödinger Equation have been observed for the first time. The experiment was performed in an optical slab waveguide with the cascaded quadratic nonlinearity in second-harmonic generation. Y1 - 2018 SN - 978-1-943580-43-9 U6 - https://doi.org/10.1364/np.2018.npth1h.7 PB - OSA CY - Washington D.C. ER - TY - JOUR A1 - Kalita, Viktor M. A1 - Snarskii, Andrei A. A1 - Shamonin (Chamonine), Mikhail A1 - Zorinets, Denis T1 - Effect of single-particle magnetostriction on the shear modulus of compliant magnetoactive elastomers JF - Physical review E N2 - The influence of an external magnetic field on the static shear strain and the effective shear modulus of a magnetoactive elastomer (MAE) is studied theoretically in the framework of a recently introduced approach to the single-particle magnetostriction mechanism [V. M. Kalita et al., Phys. Rev. E 93, 062503 (2016)]. The planar problem of magnetostriction in an MAE with magnetically soft inclusions in the form of a thin disk (platelet) having the magnetic anisotropy in the plane of this disk is solved analytically. An external magnetic field acts with torques on magnetic filler particles, creates mechanical stresses in the vicinity of inclusions, induces shear strain, and increases the effective shear modulus of these composite materials. It is shown that the largest effect of the magnetic field on the effective shear modulus should be expected in MAEs with soft elastomer matrices, where the shear modulus of the matrix is less than the magnetic anisotropy constant of inclusions. It is derived that the effective shear modulus is nonlinearly dependent on the external magnetic field and approaches the saturation value in magnetic fields exceeding the field of particle anisotropy. It is shown that model calculations of the effective shear modulus correspond to a phenomenological definition of effective elastic moduli and magnetoelastic coupling constants. The obtained theoretical results compare well with known experimental data. Determination of effective elastic coefficients in MAEs and their dependence on magnetic field is discussed. The concentration dependence of the effective shear modulus at higher filler concentrations has been estimated using the method of Pade approximants, which predicts that both the absolute and relative changes of the magnetic-field-dependent effective shear modulus will significantly increase with the growing concentration of filler particles. KW - BEHAVIOR KW - composites KW - DEPENDENCE KW - FERROGELS KW - MECHANICAL-PROPERTIES KW - MICROSTRUCTURE KW - Polymer KW - PURE SHEAR KW - RHEOLOGY KW - SENSITIVE ELASTOMERS Y1 - 2017 U6 - https://doi.org/10.1103/PhysRevE.95.032503 VL - 95 IS - 3 PB - American Physical Society ER - TY - JOUR A1 - Bodnaruk, Andrii V. A1 - Brunhuber, Alexander A1 - Kalita, Viktor M. A1 - Kulyk, Mykola M. A1 - Snarskii, Andrei A. A1 - Lozenko, Albert F. A1 - Ryabchenko, Sergey M. A1 - Shamonin (Chamonine), Mikhail T1 - Temperature-dependent magnetic properties of a magnetoactive elastomer: Immobilization of the soft-magnetic filler JF - Journal of Applied Physics N2 - The magnetic properties of a magnetoactive elastomer (MAE) filled with mu m-sized soft-magnetic iron particles have been experimentally studied in the temperature range between 150 K and 310 K. By changing the temperature, the elastic modulus of the elastomer matrix was modified, and it was possible to obtain magnetization curves for an invariable arrangement of particles in the sample and in the case when the particles were able to change their position within the MAE under the influence of magnetic forces. At low (less than 220 K) temperatures, when the matrix becomes rigid, the magnetization of the MAE does not show a hysteresis behavior, and it is characterized by a negative value of the Rayleigh constant. At room temperature, when the polymer matrix is compliant, a magnetic hysteresis exists where the dependence of the differential magnetic susceptibility on the magnetic field exhibits local maxima. The appearance of these maxima is explained by the elastic resistance of the matrix to the displacement of particles under the action of magnetic forces. KW - BEHAVIOR KW - composites KW - FIELD KW - GELS KW - hysteresis KW - Magnetorheological elastomers KW - MICROSTRUCTURE KW - PERMEABILITY KW - RAYLEIGH LAW KW - STRAIN Y1 - 2018 U6 - https://doi.org/10.1063/1.5023891 VL - 123 IS - 11 PB - AIP Publishing ER - TY - JOUR A1 - Kalita, Viktor M. A1 - Snarskii, Andrei A. A1 - Zorinets, Denis A1 - Shamonin (Chamonine), Mikhail T1 - Single-particle mechanism of magnetostriction in magnetoactive elastomers JF - Physical Review E N2 - Magnetoactive elastomers (MAEs) are composite materials comprised of micrometer-sized ferromagnetic particles in a nonmagnetic elastomermatrix. Asingle-particle mechanism ofmagnetostriction in MAEs, assuming the rotation of a soft magnetic, mechanically rigid particle with uniaxial magnetic anisotropy in magnetic fields is identified and considered theoretically within the framework of an alternative model. In this mechanism, the total magnetic anisotropy energy of the filling particles in the matrix is the sum over single particles. Matrix displacements in the vicinity of the particle and the resulting direction of the magnetization vector are calculated. The effect of matrix deformation is pronounced well if the magnetic anisotropy coefficient K is much larger than the shear modulus mu of the elastic matrix. The feasibility of the proposed magnetostriction mechanism in soft magnetoactive elastomers and gels is elucidated. The magnetic-field-induced internal stresses in the matrix lead to effects of magnetodeformation and may increase the elastic moduli of these composite materials. KW - BEHAVIOR KW - Deformation KW - DEPENDENCE KW - FERROGELS KW - HOMOGENEOUS MAGNETIC-FIELD KW - magnetodeformation KW - MICROSTRUCTURE KW - SENSITIVE ELASTOMERS Y1 - 2016 U6 - https://doi.org/10.1103/PhysRevE.93.062503 VL - 93 IS - 6 PB - American Physical Society ER - TY - CHAP A1 - Setzpfandt, Frank A1 - Solntsev, Alexander S. A1 - Titchener, James A1 - Wu, Che W. A1 - Xiong, Chunle A1 - Pertsch, Thomas A1 - Schiek, Roland A1 - Neshev, Dragomir N. A1 - Sukhorukov, Andrey A. T1 - Optically tunable entangled photon state generation in a nonlinear directional coupler T2 - CLEO: QELS_Fundamental Science 2015, San Jose, California, United States, 10-15 May 2015 N2 - We propose and experimentally demonstrate an all-optically tunable biphoton quantum light source using a nonlinear directional coupler. The source can generate high-fidelity N00N states, completely split states, and states with variable degrees of entanglement. Y1 - 2015 SN - 978-1-55752-968-8 U6 - https://doi.org/10.1364/cleo_qels.2015.fth4d.3 PB - OSA CY - Washington, D.C. ER - TY - CHAP A1 - Setzpfandt, Frank A1 - Solntsev, Alexander S. A1 - Titchener, James A1 - Wu, Che Wen A1 - Xiong, Chunle A1 - Pertsch, Thomas A1 - Schiek, Roland A1 - Neshev, Dragomir N. A1 - Sukhorukov, Andrey A. T1 - Optically Tunable Entangled Photon State Generation in a Nonlinear Directional Coupler T2 - Nonlinear Optics [Kauai, Hawaii 26-31 July 2015] N2 - We propose and experimentally demonstrate an all-optically tunable biphoton quantum light source using a nonlinear directional coupler. The source can generate high-fidelity N00N states, completely split states, and states with variable degrees of entanglement. Y1 - 2015 SN - 978-1-55752-001-2 U6 - https://doi.org/10.1364/nlo.2015.nw2a.4 IS - paper NW2A.4 PB - OSA CY - Washington, D.C. ER - TY - CHAP A1 - Setzpfandt, Frank A1 - Schiek, Roland A1 - Sohler, Wolfgang A1 - Pertsch, Thomas T1 - Nonlinear Nearest-Neighbor Coupling in Quadratic Waveguide Arrays T2 - Nonlinear Optics : Proceedings Nonlinear Optics 26-31 July 2015, Kauai, Hawaii, United States N2 - We investigate nonlinear coupling between neighboring waveguides in waveguide arrays with second-order nonlinearity. Using mode symmetries to suppress local nonlinearities, we experimentally show the profound effect of such nonlinear nearest-neighbor interactions on second-harmonic generation. Y1 - 2015 SN - 978-1-55752-001-2 U6 - https://doi.org/10.1364/nlo.2015.nm3b.6 PB - OSA CY - Washington, D.C. ER - TY - CHAP A1 - Schiek, Roland A1 - Setzpfandt, Frank A1 - Baronio, Fabio T1 - Akhmediev Breathers and Modulation Instability’s Growth-Decay Cycle in Slab Waveguides T2 - Nonlinear Optics : 15-19 July 2019, Waikoloa Beach, Hawaii, United States N2 - Optical film waveguides served as new platform for investigating Akhmediev Breathers. Using the interplay between third-order and cascaded second-order optical nonlinearities breathers and modulation instability cycles in a wide nonlinear regime were characterized. Y1 - 2019 SN - 978-1-943580-62-0 U6 - https://doi.org/10.1364/nlo.2019.ntu2a.2 PB - OSA CY - Washington, D.C. ER - TY - JOUR A1 - Saveliev, Dmitry A1 - Fetisov, Leonid Y. A1 - Chashin, Dmitri V. A1 - Fetisov, Yuri K. A1 - Khon, Anastasia A1 - Shamonin (Chamonine), Mikhail T1 - Effects of ferromagnetic-material thickness on magnetoelectric voltage transformation in a multiferroic heterostructure JF - Smart Materials and Structures N2 - A magnetoelectric (ME) voltage transformer is fabricated on the basis of a ferromagnetic (FM)-piezoelectric (PE) heterostructure comprising two equally thick laminated layers of an amorphous FM alloy and a piezoceramic lead zirconate-titanate layer sandwiched between them. The structure, placed inside an excitation coil, is electrically poled and magnetized in the direction of the long axis. The primary voltage is applied to the coil and the secondary voltage is measured between the electrodes of the PE material. It is shown for the first time that the change in the total thickness of magnetic layers significantly influences the transformer ' s characteristics. At the largest total thickness of FM layers of 138 mu m, the open-circuit voltage transformation ratio K has a maximum value of about 20, and the power transfer efficiency eta at a matched resistive load of about 20 k omega reaches 45%. The variation of the control magnetic field in the range of 0-21.6 kA m(-1) makes it possible to change the voltage transformation ratio K from zero to the maximum value. A simple model allows one to calculate the dependence of the characteristics of the ME transformer on the frequency of the primary voltage, thickness of the FM layers, control magnetic field, and the load. KW - magnetoelectric effect KW - magnetostriction KW - multiferroic heterostructure KW - piezoelectric effect KW - voltage transformer Y1 - 2021 U6 - https://doi.org/10.1088/1361-665X/abf6c0 VL - 30 IS - 6 PB - IOP PUBLISHING ER - TY - JOUR A1 - Belyaeva, Inna A. A1 - Klepp, Jürgen A1 - Lemmel, Hartmut A1 - Shamonin (Chamonine), Mikhail T1 - Feasibility of Probing the Filler Restructuring in Magnetoactive Elastomers by Ultra-Small-Angle Neutron Scattering JF - Applied Sciences N2 - Ultra-small-angle neutron scattering (USANS) experiments are reported on isotropic magnetoactive elastomer (MAE) samples with different concentrations of micrometer-sized iron particles in the presence of an in-plane magnetic field up to 350 mT. The effect of the magnetic field on the scattering curves is observed in the scattering vector range between 2.5 x 10(-5) and 1.85 x 10(-4) angstrom(-1). It is found that the neutron scattering depends on the magnetization history (hysteresis). The relation of the observed changes to the magnetic-field-induced restructuring of the filler particles is discussed. The perspectives of employing USANS for investigations of the internal microstructure and its changes in magnetic field are considered. KW - Anisotropy KW - Ferrofluids KW - hysteresis KW - magnetoactive elastomer KW - magnetorheological elastomer KW - Matrix KW - MIicrostructure KW - restructuring of the filler KW - ultra-small-angle neutron scattering Y1 - 2021 U6 - https://doi.org/10.3390/app11104470 VL - 11 IS - 10 SP - 1 EP - 9 PB - MDPI CY - Basel ER - TY - JOUR A1 - Saveliev, Dmitri A1 - Chashin, Dmitri V. A1 - Fetisov, Leonid Y. A1 - Shamonin (Chamonine), Mikhail A1 - Fetisov, Yuri K. T1 - Ceramic-Heterostructure-Based Magnetoelectric Voltage Transformer with an Adjustable Transformation Ratio JF - Materials N2 - A voltage transformer employing the magnetoelectric effect in a composite ceramic heterostructure with layers of a magnetostrictive nickel–cobalt ferrite and a piezoelectric lead zirconate–titanate is described. In contrast to electromagnetic and piezoelectric transformers, a unique feature of the presented transformer is the possibility of tuning the voltage transformation ratio K using a dc magnetic field. The dependences of the transformer characteristics on the frequency and the amplitude of the input voltage, the strength of the control magnetic field and the load resistance are investigated. The transformer operates in the voltage range between 0 and 112 V, and the voltage transformation ratio K is tuned between 0 and 14.1 when the control field H changes between 0 and 6.4 kA/m. The power at the transformer output reached 63 mW, and the power conversion efficiency was 34%. The methods for calculation of the frequency response, and the field and load characteristics of the transformer are proposed. The ways to improve performance characteristics of magnetoelectric transformers and their possible application areas are discussed. KW - magnetoelectric effect KW - piezoelectric effect KW - voltage transformer KW - composite material KW - magnetostriction Y1 - 2020 U6 - https://doi.org/10.3390/ma13183981 VL - 13 IS - 18 SP - 1 EP - 13 PB - MDPI ER - TY - JOUR A1 - Snarskii, Andrei A. A1 - Shamonin (Chamonine), Mikhail A1 - Yuskevich, Pavel T1 - Effective medium theory for the elastic properties of composite materials with various percolation thresholds JF - Materials N2 - It is discussed that the classical effective medium theory for the elastic properties of random heterogeneous materials is not congruous with the effective medium theory for the electrical conductivity. In particular, when describing the elastic and electro-conductive properties of a strongly inhomogeneous two-phase composite material, the steep rise of effective parameters occurs at different concentrations. To achieve the logical concordance between the cross-property relations, a modification of the effective medium theory of the elastic properties is introduced. It is shown that the qualitative conclusions of the theory do not change, while a possibility of describing a broader class of composite materials with various percolation thresholds arises. It is determined under what conditions there is an elasticity theory analogue of the Dykhne formula for the effective conductivity. The theoretical results are supported by known experiments and show improvement over the existing approach. The introduction of the theory with the variable percolation threshold paves the way for describing the magnetorheological properties of magnetoactive elastomers. A similar approach has been recently used for the description of magneto-dielectric and magnetic properties. KW - elastic properties KW - effective medium approximation KW - self-consistent KW - random heterogeneous medium KW - two-phase composite material KW - percolation threshold Y1 - 2020 U6 - https://doi.org/10.3390/ma13051243 VL - 13 IS - 5 SP - 1 EP - 19 PB - MPDI CY - Basel ER - TY - JOUR A1 - Snarskii, Andrei A. A1 - Shamonin (Chamonine), Mikhail A1 - Yuskevich, Pavel A1 - Saveliev, Dmitry V. A1 - Belyaeva, Inna A. T1 - Induced anisotropy in composite materials with reconfigurable microstructure: Effective medium model with movable percolation threshold JF - Physica A: Statistical Mechanics and its Applications N2 - In composite materials, with field-dependent restructuring of the filler material (changes in the mutual arrangement of inclusions), the presence of an external magnetic field induces anisotropy of the dielectric properties, even if the composite is isotropic in the absence of an external field. A modified effective medium approximation is proposed for the calculation of the components of effective permittivity within a class of composites with reconfigurable microstructure, where both phases (the filler and the matrix) are isotropic and the inclusions have spherical shape. The effective physical properties are calculated in the parallel and perpendicular directions to an applied field. The appearance of the anisotropy of the permittivity is simulated by the introduction of two not-equal, possibly variable (field-dependent) percolation thresholds. The implications, of the proposed theoretical approach, are demonstrated for the case of the dielectric properties of magnetoactive elastomers (MAEs). In MAEs with soft polymer matrices, the mutual arrangement of micrometer-sized magnetic inclusions can significantly change in an applied magnetic field. A reasonable agreement between theory and experiment at a measurement frequency of 1 kHz is found, and is improved in comparison to the previous models. The components of the effective permittivity tensor, characterizing the dielectric properties along the direction of the applied magnetic field and in the orthogonal direction, grow with an increasing field. This growth is more pronounced for the permittivity component in the field direction. The possible extensions of the theoretical model and future directions of research are discussed. The presented theoretical approach can be useful for the application-driven development of a number of smart materials, in particular electro- and magnetorheological gels, elastomers and fluids. KW - Effective medium theory KW - Magnetoactive elastomer KW - Percolation threshold KW - Anisotropy KW - Effective permittivity KW - Random heterogeneous medium Y1 - 2020 U6 - https://doi.org/10.1016/j.physa.2020.125170 VL - 560 IS - December PB - Elsevier ER - TY - JOUR A1 - Saveliev, Dmitry V. A1 - Belyaeva, Inna A. A1 - Chashin, Dmitri V. A1 - Fetisov, Leonid Y. A1 - Romeis, Dirk A1 - Kettl, Wolfgang A1 - Kramarenko, Elena Yu A1 - Saphiannikova, M. A1 - Stepanov, Gennady V. A1 - Shamonin (Chamonine), Mikhail T1 - Giant extensional strain of magnetoactive elastomeric cylinders in uniform magnetic fields JF - Materials N2 - Elongations of magnetoactive elastomers (MAEs) under ascending–descending uniform magnetic fields were studied experimentally using a laboratory apparatus specifically designed to measure large extensional strains (up to 20%) in compliant MAEs. In the literature, such a phenomenon is usually denoted as giant magnetostriction. The synthesized cylindrical MAE samples were based on polydimethylsiloxane matrices filled with micrometer-sized particles of carbonyl iron. The impact of both the macroscopic shape factor of the samples and their magneto-mechanical characteristics were evaluated. For this purpose, the aspect ratio of the MAE cylindrical samples, the concentration of magnetic particles in MAEs and the effective shear modulus were systematically varied. It was shown that the magnetically induced elongation of MAE cylinders in the maximum magnetic field of about 400 kA/m, applied along the cylinder axis, grew with the increasing aspect ratio. The effect of the sample composition is discussed in terms of magnetic filler rearrangements in magnetic fields and the observed experimental tendencies are rationalized by simple theoretical estimates. The obtained results can be used for the design of new smart materials with magnetic-field-controlled deformation properties, e.g., for soft robotics. KW - magnetostriction KW - magnetoactive elastomer KW - extensional strain KW - hysteresis KW - magnetomechanical effect KW - magnetodeformation Y1 - 2020 U6 - https://doi.org/10.3390/ma13153297 SN - 1996-1944 N1 - Corresponding author: Mikhail Shamonin VL - 13 IS - 15 SP - 1 EP - 17 PB - MDPI CY - Basel ER - TY - JOUR A1 - Saveliev, Dmitry V. A1 - Belyaeva, Inna A. A1 - Chashin, Dmitri V. A1 - Fetisov, Leonid Y. A1 - Shamonin (Chamonine), Mikhail T1 - Large Wiedemann effect in a magnetoactive elastomer JF - Journal of Magnetism and Magnetic Materials N2 - Large twists of a soft tube (hollow cylinder) in helical magnetic fields are presented for the first time. Such a phenomenon is usually denoted as the Wiedemann effect. The tube is fabricated from a soft magnetoactive elastomer material with the shear modulus of about 56 kPa. The composite material comprises 80 mass% of micrometer-sized iron particles embedded into a polydimethylsiloxane matrix. The circular magnetic field is generated by an electric current in a straight wire passing through the inner hole of the tube. The maximum value of approximately 350″/cm is observed in a longitudinal magnetic field of a few kA/m overlapped with a circumferential magnetic field of about 1.4 kA/m on the surface of the inner hole. A pronounced hysteresis in the dependence of the Wiedemann effect on the circular magnetic field is found. The ways to enhance the Wiedemann twist in magnetoactive elastomers are discussed. The observed large effect is promising for application in magnetic-field controlled torsional actuators, in particular for soft robotics. Y1 - 2020 U6 - https://doi.org/10.1016/j.jmmm.2020.166969 VL - 511 IS - October PB - Elsevier ER - TY - JOUR A1 - Kurzweil, Peter A1 - Schottenbauer, Josef A1 - Schell, Christian T1 - Past, Present and Future of Electrochemical Capacitors: Pseudocapacitance, Aging Mechanisms and Service Life Estimation JF - Journal of Energy Storage N2 - The capacitance values printed on capacitor housings do not reflect the actual capacitance available for any technical application. The complex properties of the pseudocapacitance and the aging behavior of practical supercapacitors are reviewed with regard to the state-of-the-art and the latest findings. The long-term stability of various electrolyte systems and carbon materials is critically examined under phenomenological aspects that reflect the typical fault pattern of supercapacitors. Electrolyte resistance and voltammetric capacitance are reliable aging indicators. High temperatures have a greater impact on service life than high voltages, and overvoltages are worse than high currents. The anode more than the cathode suffers from a loss of pore volume, increase of nitrogen and fluorine compounds, and the unstable adhesive layer between active carbon and aluminum. Unwanted material changes and chemical reactions in the supercapacitor reflect the influence of water over several years in the life test. Credible reaction pathways are identified for the known aging processes. Fundamentals and materials are reviewed in a separate part.** KW - Electrochemical double-layer capacitors KW - Supercapacitor KW - Capacitance KW - Pseudocapacitance KW - Aging mechanisms KW - Carbon degradation KW - State-of-health Review KW - Review Y1 - 2020 U6 - https://doi.org/10.1016/j.est.2021.102311 VL - 35 IS - March PB - Elsevier ER - TY - CHAP A1 - Kinoshita, Keisuke A1 - Delcroix, Marc A1 - Gannot, Sharon A1 - Habets, Emanuël A. P. A1 - Haeb-Umbach, Reinhold A1 - Kellermann, Walter A1 - Leutnant, Volker A1 - Maas, Roland A1 - Nakatani, Tomohiro A1 - Raj, Bhiksha A1 - Sehr, Armin A1 - Yoshioka, Takuya ED - Watanabe, Shinji ED - Delcroix, Marc ED - Metze, Florian ED - Hershey, John R. T1 - The REVERB Challenge: A Benchmark Task for Reverberation-Robust ASR Techniques T2 - New Era for Robust Speech Recognition N2 - The REVERB challenge is a benchmark task designed to evaluate reverberation-robust automatic speech recognition techniques under various conditions. A particular novelty of the REVERB challenge database is that it comprises both real reverberant speech recordings and simulated reverberant speech, both of which include tasks to evaluate techniques for 1-, 2-, and 8-microphone situations. In this chapter, we describe the problem of reverberation and characteristics of the REVERB challenge data, and finally briefly introduce some results and findings useful for reverberant speech processing in the current deep-neural-network era. Y1 - 2017 SN - 978-3-319-64679-4 U6 - https://doi.org/10.1007/978-3-319-64680-0_15 VL - 27 SP - 345 EP - 354 PB - Springer CY - Cham ER - TY - CHAP A1 - Schiedermeier, Maximilian A1 - Rettner, Cornelius A1 - Steiner, Marcel A1 - März, Martin T1 - Dual-inverter control synchronization strategy to minimize the DC-link capacitor current T2 - 2020 IEEE Vehicle Power and Propulsion Conference (VPPC), 18 November 2020 - 16 December 2020, Gijon, Spain N2 - This paper proposes the possible switching synchronization strategies of an automotive dual-inverter against the background of minimizing the RMS DC-link capacitor current. The publication mainly focuses on the straight-ahead motion of a rear axle with one electric drive per wheel. In addition to it, a dual-inverter consisting of two subinverters with a common DC-link capacitor is taken into consideration. These sub-inverters each have three phases and are based on a 2-level voltage-source-topology. To control the electrical machines, the continuous Space-Vector-Modulation strategy is used. For this application, different control signal synchronization strategies of the two sub-inverters of the dualinverter are presented. Apart from the existing strategies, this paper proposes a new method, which inherits a compromise between low complexity and high effectiveness. In contrast to previous publications, the resulting capacitor currents are quantified and subsequentlyevaluated. This novel quantification, which is dependent on the dual-inverter’s operating point, provides a base for targeted dimensioning of the capacitor. Moreover, this forms the foundation for further investigations of vehicle’s cornering, as well as for the possible synchronization of stand-alone inverters. In the context of this publication, the presented results are verified by experimentally determined data of a motor-inverter system. KW - Axles KW - Capacitors KW - Complexity theory KW - DC-link capacitor KW - Dual-inverter KW - interleaved inverters KW - Inverters KW - space vector modulation (SVM) KW - Switches KW - Synchronization KW - Voltage source inverter (VSI) KW - Wheels Y1 - 2020 U6 - https://doi.org/10.1109/VPPC49601.2020.9330921 SP - 1 EP - 6 PB - IEEE ER - TY - JOUR A1 - Monkman, Gareth J. A1 - Sindersberger, Dirk A1 - Prem, Nina A1 - Szecsey, Tamara T1 - Smart Stiction JF - Robotics & Automation Engineering Journal N2 - Soft robotics could loosely be described as the engineering science of expanded dexterity through controllable flexibility. The exploitation of controllable compliance through the judicious choice of soft flexible members, as opposed to a finite number of rigid kinematic joints, can result in greater dexterity without compromising simplicity. One example is the replacement of segmented mechanical legs with simple compliant material eruciform prolegs. To achieve this in robotics, without introducing additional mechanical joints, mobile surfaces with switchable coefficients of friction is essential. This paper explains how, using silicone based smart materials, the rapid alternation between kinematic and static friction (stiction) may be achieved. Y1 - 2019 U6 - https://doi.org/10.19080/RAEJ.2019.04.555641 N1 - Corresponding author: Gareth J. Monkman VL - 4 IS - 4 PB - Juniper Publishers ER - TY - JOUR A1 - Snarskii, Andrei A. A1 - Zorinets, Denis A1 - Shamonin (Chamonine), Mikhail A1 - Kalita, Viktor M. T1 - Theoretical method for calculation of effective properties of composite materials with reconfigurable microstructure BT - Electric and magnetic phenomena JF - Physica A: Statistical Mechanics and its Applications N2 - We propose a theoretical approach for calculating effective electric and magnetic properties of composites, with field dependent restructuring of the filler. The theory combines the effective medium approximation, extended to a field-dependent (variable) percolation threshold, with an approximate treatment of the nonlinearity of material properties. Theoretical results are compared with experiments on magnetorheological elastomers, which in the context of investigated phenomena are often called magnetoactive elastomers (MAEs). In MAEs with soft polymer matrices, the mutual arrangement of inclusions changes in an applied magnetic field. This reorganization of the microstructure leads to unconventionally large changes of electrical and magnetic properties. The obtained theoretical results describe observed phenomena in MAEs well. For the magnetodielectric effect, qualitative agreement between theory and experiment is demonstrated. In the case of magnetic permeability, quantitative agreement is achieved. The theoretical approach presented can be useful for the development of field-controlled smart materials and design of intelligent structures on their basis, because the field dependence of physical properties can be predicted. (C) 2019 Elsevier B.V. All rights reserved. KW - CONDUCTIVITY KW - EFFECTIVE RESPONSE KW - magnetoactive elastomers KW - PERCOLATION KW - PERMEABILITY Y1 - 2019 U6 - https://doi.org/10.1016/j.physa.2019.122467 VL - 535 IS - December PB - Elsevier ER - TY - JOUR A1 - Kostrov, Sergei A. A1 - Shamonin (Chamonine), Mikhail A1 - Stepanov, Gennady V. A1 - Kramarenko, Elena Yu T1 - Magnetodielectric Response of Soft Magnetoactive Elastomers: Effects of Filler Concentration and Measurement Frequency JF - International Journal of Molecular Sciences N2 - The magnetodielectric response of magnetoactive elastomers (MAEs) in its dependence on filler concentration, magnetic field, and test frequency is studied experimentally. MAEs are synthesized on the basis of a silicone matrix filled with spherical carbonyl iron particles characterized by a mean diameter of 4.5 mu m. The concentration of the magnetic filler within composite materials is equal to 70, 75, and 80 mass%. The effective lossless permittivity epsilon as well as the dielectric loss tan grow significantly when the magnetic field increases. The permittivity increases and the dielectric loss decreases with increasing filler concentration. In the measurement frequency range between 1 kHz and 200 kHz, the frequency hardly affects the values of epsilon and tan in the absence of a magnetic field. However, both parameters decrease considerably with the growing frequency in a constant magnetic field. The more strongly the magnetic field is applied, the larger the change in permittivity and loss tangent at the same test frequency is observed. An equivalent circuit formulation qualitatively describes the main tendencies of the magnetodielectric response. KW - dielectric loss KW - magnetic filler KW - MAGNETIC-FIELD KW - magnetoactive elastomers KW - magnetodielectric effect KW - permittivity Y1 - 2019 U6 - https://doi.org/10.3390/ijms20092230 VL - 20 IS - 9 SP - 1 EP - 13 PB - MDPI CY - Basel ER - TY - JOUR A1 - Sindersberger, Dirk A1 - Prem, Nina A1 - Monkman, Gareth J. T1 - Structure formation in low concentration magnetoactive polymers JF - AIP advances N2 - This paper concerns recent research into the autonomous formation of micro-structures in low carbonyl iron powder (CIP) concentration magneto active polymers (MAP). Higher concentrations of CIP show an isotropic distribution of magnetic filler throughout the entire sample, while autonomous structure formation is possible at mass concentrations lower than 3%. The formation of micro-toroids commences as CIP concentration approaches 1% wt. Further development of coherent rings with a defined order follow as CIP concentrations increase toward 2% wt, whilst exceeding 3% wt leads to the same isotropic distribution found in higher concentration MAP. Structured samples containing between 1% wt and 3% wt CIP were investigated using X-Ray tomography where solitary structures could clearly be observed. The ring structures represent microinductivities whose geometries can be manipulated during fabrication. In addition, these structures are magnetic field sensitive. This is not only relevant to applications in the GHz and THz areas but recent research has revealed implications for optical, thermal, acoustic and even chemical MAP sensors. (C) 2019 Author(s). Y1 - 2019 U6 - https://doi.org/10.1063/1.5079997 N1 - Corresponding author: Dirk Sindersberger VL - 9 IS - 3 PB - AIP Publishing ER - TY - JOUR A1 - Bodnaruk, Andrii V. A1 - Kalita, Viktor M. A1 - Kulyk, Mykola M. A1 - Lozenko, Albert F. A1 - Ryabchenko, Sergey M. A1 - Snarskii, Andrei A. A1 - Brunhuber, Alexander A1 - Shamonin (Chamonine), Mikhail T1 - Temperature blocking and magnetization of magnetoactive elastomers JF - Journal of Magnetism and Magnetic Materials N2 - The magnetization of a magnetoactive elastomer (MAE) with microparticles of soft magnetic carbonyl iron embedded in a highly elastic matrix has been studied. It is shown that at high temperatures its magnetization curve has the form of a specific hysteresis loop. This hysteresis is attributed to the influence of displacement of magnetized particles in the elastically soft elastomer matrix under the effect of magnetic forces, leading to the change of magnetic interaction between the particles. In this case, there is a maximum in the field dependence of the magnetic susceptibility, the occurrence of which has been associated with the competition between rearrangement of particles, when they are displaced in a magnetic field, and saturation of particles' magnetization. When the MAE is cooled below approximately 225 K, both the magnetic hysteresis and the maximum in the field dependence of the magnetic susceptibility disappear. When the MAE material is cooled below the solidification temperature of the elastomer matrix, the displacements of the magnetic particles during magnetization are blocked by the rigid matrix. The magnetization reversal of the MAE is reversible. This means that the shape of subsequent magnetization loops remains constant and the sample returns into the initial non-magnetized state after the magnetic field is turned off. KW - Hysteresis loop KW - Magnetization reversal KW - magnetoactive elastomer KW - Magnetorheological elastomers KW - MICROSTRUCTURE KW - Solidification Y1 - 2019 U6 - https://doi.org/10.1016/j.jmmm.2018.10.005 VL - 471 IS - February SP - 464 EP - 467 PB - Elsevier ER - TY - JOUR A1 - Fetisov, Yuri K. A1 - Chashin, Dmitri V. A1 - Saveliev, Dmitri A1 - Fetisov, Leonid Y. A1 - Shamonin (Chamonine), Mikhail T1 - Anisotropic Magnetoelectric Effect in a Planar Heterostructure Comprising Piezoelectric Ceramics and Magnetostrictive Fibrous Composite JF - Materials N2 - The direct magnetoelectric (ME) effect is investigated in a planar structure comprising mechanically coupled layers of a magnetostrictive fibrous composite (MFC) and a piezoelectric ceramics (lead zirconate titanate, PZT). The MFC is an array of Ni-wires with a diameter of 200 mu m that are aligned parallel to each other in a single layer. The wires are separated by a distance of 250 or 500 mu m and fixed in a polyamide matrix. The structure was placed in a tangential constant field H and was excited by an alternating magnetic field h parallel to H, while the voltage generated by the PZT layer was measured. The resulting field dependences of the magnetization M(H) and the magnetostriction lambda(H) were determined by the orientation of the field H in the plane of the structure and the distance between the Ni-wires. The ME coupling coefficient of the structure decreased from 4.8 to 0.25 V/A when the orientation of H was changed from parallel to perpendicular to Ni-wires. With an increase in the excitation field amplitude h, a nonlinear ME effect in the output voltage, namely frequency doubling, was observed. The frequency and field dependences of the efficiency of the ME transduction in the MFC-piezoelectric heterostructure are well described by the existing theory. KW - composite KW - frequency doubling KW - heterostructure KW - magnetoelectric effect KW - magnetostrictive fiber KW - piezoelectric ceramic material Y1 - 2019 U6 - https://doi.org/10.3390/ma12193228 N1 - Corresponding authors: Yuri Fetisov, Mikhail Shamonin VL - 12 IS - 19 SP - 1 EP - 13 PB - MDPI CY - Basel ER - TY - JOUR A1 - Prem, Nina A1 - Sindersberger, Dirk A1 - Monkman, Gareth J. T1 - Mini-Extruder for 3D Magnetoactive Polymer Printing JF - Advances in Materials Science and Engineering N2 - This work describes the development of a new miniature extruder, essential to cavity-free 3D printing of silicone-based smart materials. This makes the 3D printing of magnetoactive and electroactive polymer soft robotic components and devices directly from CAD data possible. The special feature of such an extruder is that it is designed for use with addition-crosslinking RTV-2 silicones, including solid particulate additives. The extruder merges the respective components automatically during extrusion which obviates the need for premixing and vacuum evacuation. Problems associated with inhomogeneities and unwanted cavity production are consequently eliminated. Rheological details necessary to the design, together with some preliminary performance results, are presented. Y1 - 2019 U6 - https://doi.org/10.1155/2019/8715718 N1 - Corresponding author: Gareth J. Monkman SP - 1 EP - 8 PB - HINDAWI ER - TY - JOUR A1 - Bodnaruk, A1 - Andrii V., A1 - Brunhuber, Alexander A1 - Kalita, Viktor M. A1 - Kulyk, Mykola M. A1 - Kurzweil, Peter A1 - Snarskii, Andrei A. A1 - Lozenko, Albert F. A1 - Ryabchenko, Sergey M. A1 - Shamonin (Chamonine), Mikhail T1 - Magnetic anisotropy in magnetoactive elastomers, enabled by matrix elasticity JF - Polymer N2 - Polydimethylsiloxane based magnetoactive elastomers demonstrate above the melting transition range (e.g. at room temperature) an induced uniaxial magnetic anisotropy, which grows with increasing magnetic field. By freezing a material down to 150 K, displaced iron microparticles are immobilized, so that the magnetic anisotropy can be measured. Magnetic anisotropy “constant” is a consequence of particle displacements and a characteristic of the energy of internal deformations in the polymer matrix. The maximum anisotropy constant of the filling is at least one order of magnitude larger than the shear modulus of the pure elastomer (matrix). In a magnetic field, the gain in the rigidity of the composite material is attributed to the magnetomechanical coupling, which is in turn a source of anisotropy. The concept of effective magnetic field felt by the magnetization allows one to explain the magnetization curve at room temperature from low-temperature measurements. The results can be useful for developing vibration absorbers and isolators. KW - Experimental methodology KW - Internal deformation KW - magnetic properties KW - magnetoactive elastomer KW - Magnetomechanical coupling KW - magnetorheological elastomer Y1 - 2019 U6 - https://doi.org/10.1016/j.polymer.2018.12.027 VL - 162 IS - January SP - 63 EP - 72 PB - Elsevier ER - TY - JOUR A1 - Schiek, Roland A1 - Baronio, Fabio T1 - Spatial Akhmediev breathers and modulation instability growth-decay cycles in a quadratic optical medium JF - Physical Review Research N2 - We investigate the spatial nonlinear localization of light on a quasi-plane-wave background with a harmonic perturbation induced by modulation instability in a quadratic nonlinear optical medium. In particular, we demonstrate experimentally the excitation of deterministic Akhmediev breathers and thus the growth-decay dynamics of modulation instability in a LiNbO3 slab waveguide. The results should stimulate new interest in modulation instability, extreme events, turbulence, recurrence, and supercontinuum generation in quadratic nonlinear optics. Y1 - 2019 U6 - https://doi.org/10.1103/PhysRevResearch.1.032036 VL - 1 IS - 3 SP - 1 EP - 5 PB - American Physical Society ER - TY - JOUR A1 - Jordaan, Joshua A1 - Punzet, Stefan A1 - Melnikov, Anton A1 - Sanches, Alexandre A1 - Oberst, Sebastian A1 - Marburg, Steffen A1 - Powell, David A. T1 - Measuring monopole and dipole polarizability of acoustic meta-atoms JF - Applied physics letters N2 - We present a method to extract monopole and dipole polarizability from experimental measurements of two-dimensional acoustic meta-atoms. In contrast to extraction from numerical results, this enables all second-order effects and uncertainties in material properties to be accounted for. We apply the technique to 3D-printed labyrinthine meta-atoms of a variety of geometries. We show that the polarizability of structures with a shorter acoustic path length agrees well with numerical results. However, those with longer path lengths suffer strong additional damping, which we attribute to the strong viscous and thermal losses in narrow channels. KW - METASURFACE KW - SOUND Y1 - 2018 U6 - https://doi.org/10.1063/1.5052661 VL - 113 IS - 22 PB - AIP Publishing ER - TY - JOUR A1 - Sindersberger, Dirk A1 - Diermeier, Andreas A1 - Prem, Nina A1 - Monkman, Gareth J. T1 - Printing of hybrid magneto active polymers with 6 degrees of freedom JF - Materials today communications N2 - 3D printing techniques offer a versatile method for the fabrication and structuring of magnetoactive polymer (MAP) components and devices for research prototype development. MAP materials enjoy an advantage in that the particulate content may be manipulated by external magnetic fields during the forming and curing processes. Controlled particle diffusion within the polymer matrix, by means of external fields applied during the printing process, influences a further three spatial dimensions. This permits control of the spatial particle concentration and makes free displacement of particle accumulations possible during the crosslinking phase. Particles which are susceptible to electric or magnetic fields can thereby be shifted into regions previously free of particles. The additional 3 graded dispersion axes effectively results in what can be described as 6 degrees of freedom (6DOF) printing. Electrically conductive polymers combined with non-conductive areas, provide an additional benefit for the production of complex hybrid structures. This may be augmented by the combination of magnetically active thermoplastics as inelastic structural components together with mechanically deformable elastomers. The combination of all fabrication methods in one hybrid printing process makes the production of complex sensor and actuator systems in one manufacturing sequence possible. This far exceeds the capabilities of conventional casting and machining operations and opens new possibilities for the fabrication of soft material elements. KW - 3D printing KW - Conductive polymer KW - Hybrid KW - Magnetoactive KW - Polymer Y1 - 2018 U6 - https://doi.org/10.1016/j.mtcomm.2018.02.032 VL - 15 IS - June SP - 269 EP - 274 PB - Elsevier ER - TY - JOUR A1 - Snarskii, Andrei A. A1 - Kalita, Viktor M. A1 - Shamonin (Chamonine), Mikhail T1 - Renormalization of the critical exponent for the shear modulus of magnetoactive elastomers JF - Scientific Reports N2 - It is shown that the critical exponent for the effective shear modulus of a composite medium where a compliant polymer matrix is filled with ferromagnetic particles may significantly depend on the external magnetic field. The physical consequence of this dependence is the critical behavior of the relative magnetorheological effect. Y1 - 2018 U6 - https://doi.org/10.1038/s41598-018-22333-6 N1 - Corresponding author: Mikhail Shamonin VL - 8 SP - 1 EP - 8 PB - Nature ER - TY - JOUR A1 - Unterreitmeier, M. A1 - Nagler, O. A1 - Pfitzner, L. A1 - Weigel, R. A1 - Holmer, Rainer T1 - An acoustic emission sensor system for thin layer crack detection JF - Microelectronics Reliability N2 - We present a new method for semiconductor layer characterization enabling simultaneous crack generation and detection based on the established acoustic emission testing. In this paper, we explain the test concept and failure mechanism of diamond tip indentation with acoustic wave measurement on oxide layers by analytical modeling and computer-aided simulations. For this purpose, an innovative design of a sensor-indenter system was developed and experimentally verified. In further tests, the new acoustic crack detection method is correlated with proven optical inspection methods and the good reproducibility of the measurement is demonstrated. The high sensitivity and resolution of this method offer new opportunities for thin layer characterization at lower time and cost. The new high-efficient method can be used especially for process qualification for semiconductor wafer test, where oxide cracks can be induced by sharp probes causing electrical failure of the chip. KW - FLAT KW - INDENTATION Y1 - 2018 U6 - https://doi.org/10.1016/j.microrel.2018.07.015 VL - 88-90 IS - September SP - 16 EP - 21 PB - Pergamon-Elsevier ER - TY - JOUR A1 - Kurzweil, Peter A1 - Shamonin (Chamonine), Mikhail T1 - State-of-Charge Monitoring by Impedance Spectroscopy during Long-Term Self-Discharge of Supercapacitors and Lithium-Ion Batteries JF - Batteries N2 - Frequency-dependent capacitance C(ω) is a rapid and reliable method for the determination of the state-of-charge (SoC) of electrochemical storage devices. The state-of-the-art of SoC monitoring using impedance spectroscopy is reviewed, and complemented by original 1.5-year long-term electrical impedance measurements of several commercially available supercapacitors. It is found that the kinetics of the self-discharge of supercapacitors comprises at least two characteristic time constants in the range of days and months. The curvature of the Nyquist curve at frequencies above 10 Hz (charge transfer resistance) depends on the available electric charge as well, but it is of little use for applications. Lithium-ion batteries demonstrate a linear correlation between voltage and capacitance as long as overcharge and deep discharge are avoided. KW - aging KW - capacitance KW - self-discharge KW - state-of-charge monitoring KW - supercapacitor Y1 - 2018 U6 - https://doi.org/10.3390/batteries4030035 VL - 4 IS - 3 SP - 1 EP - 13 PB - MPDI ER - TY - JOUR A1 - Lee, Wai-Kong A1 - Schubert, Martin J. W. A1 - Ooi, Boon Yaik A1 - Ho, Stanley Jian-Qin T1 - Multi-source energy harvesting and storage for floating wireless sensor network nodes with Long Range Communication Capability JF - IEEE Transactions on Industry Applications N2 - Wireless sensor networks are widely used for environmental monitoring in remote areas. They are mainly composed of wireless sensor nodes, usually powered by batteries with limited capacity, but are expected to communicate in long range and operate for extended time periods. To overcome these limitations, many energy harvesting techniques are proposed to power wireless nodes for prolonged operation, whereas multihop techniques are utilized to extend the communication range. In this paper, a novel floating device with multisource energy harvesting technology that can be used as a wireless sensor node is proposed. The long range communication between wireless sensor nodes and a gateway is established through LoRa technology. In addition to conventional solar panels, an energy harvesting technique based on thermoelectric generators exploiting thermal differences created between water surface and materials exposed to sunlight is proposed. Energy generated from photovoltaic and thermoelectric generators is combined to power the wireless sensor node. This floating device consumes 6.6216 Wh per day when used as a wireless sensor node for the collection and transmission of environmental data. The sensor node can operate on a water surface for at least 9.6 days when it is not exposed to sunlight. During a sunny day, the floating device can harvest 8.375 Wh from solar panels and 0.425 Wh from thermoelectric generation. In other words, the floating device harvests sufficient energy to be self-sustaining during sunny days. KW - Wireless sensor networks KW - Energy harvesting KW - floating device KW - LoRa KW - sensor node KW - solar energy KW - thermoelectric generation Y1 - 2018 U6 - https://doi.org/10.1109/TIA.2018.2799 VL - 54 IS - 3 SP - 2606 EP - 2615 PB - IEEE ER - TY - CHAP A1 - Hofmann, Gerhard A1 - Scharfenberg, Georg T1 - Überlegungen zur normativen Anpassung der ISO 26262 aufgrund des autonomen Fahrens T2 - Automotive Software Kongress, 2015 N2 - In der Automobilindustrie ist neben der Elektromobilität und dem Leichtbau auch das Gebiet der Fahrerassistenz ein Zukunftsfeld. Speziell Fahrerassistenzsysteme, wie z.B. der Stauassistent, sind in Hinblick auf das autonome Fahren als dessen Vorstufe zu sehen. Aktuelle Assistenzfunktionen basieren auf der Präsenz des Fahrers. Die Fahrerassistenzsysteme sind nur durch Funktionen der Elektrik/Elektronik ermöglicht worden. Durch Maßnahmen der "Funktionalen Sicherheit" müssen Risiken, die durch Fehler der Elektrik/Elektronik zu Gefahren führen könnten, unter eine akzeptierte Grenze gesenkt werden. Die Diskussion über die gesetzlichen Grundlagen für das autonome Fahren ist erst am Anfang des öffentlichen Interesses. In diesem Zusammenhang ist es sinnvoll, die Notwendigkeit der Anpassung der bestehenden normativen Anforderungen zur funktionalen Sicherheit in die Diskussion mit einzubeziehen. Im ersten Ansatz wird in diesem Paper untersucht, ob von anderen Anwendungen mit automatisiertem Fahrbetrieb, wie er bei Schienenfahrzeugen realisiert ist, Ableitungen möglich sind. Im zweiten Ansatzpunkt wird konkret unter dem Gesichtspunkt des autonomen Fahrens zum Automobil auf die Gefahren-und Risikoanalyse, gemäß ISO 26262 Teil 3 eingegangen. Im Rahmen dieser Diskussion werden die drei Bewertungskriterien der Gefahren- und Risikoanalyse (severity, probability of exposure and controllability) im Paper beleuchtet. Es wird gezeigt, dass für autonomes Fahren ein zusätzliches Bewertungskriterium der Situationskomplexität sinnvoll ist, das das Umfeld einbezieht. Denn die Kontrollierbarkeit ist auf den Fahrer bezogen. Bei dem neuen Kriterium werden unter anderem der Einfluss durch die Verkehrsdichte sowie die Car-2-Car Kommunikation oder auch Fehler bzw. Ausfälle in der Car-2-X Kommunikation (zur Infrastruktur) berücksichtigt. KW - Automobilindustrie KW - autonomes Fahren KW - Elektrik KW - Elektromobilität KW - Fahrerassistenzsystem KW - funktionale Sicherheit KW - Infrastruktur KW - Leichtbau KW - Risikoanalyse KW - Schienenfahrzeug KW - Schienenverkehr KW - Verkehrsdichte Y1 - 2015 SP - 1 EP - 6 PB - WEKA Fachmedien CY - Haar ER - TY - JOUR A1 - Forster, Eva A1 - Mayer, Matthias A1 - Rabindranath, Raman A1 - Böse, Holger A1 - Schlunck, Günther A1 - Monkman, Gareth J. A1 - Shamonin (Chamonine), Mikhail T1 - Patterning of ultrasoft, agglutinative magnetorheological elastomers JF - Journal of applied polymer science N2 - A low-cost wax-cast molding technique for structuring ultrasoft (Young’s modulus ≤ 40 kPa), agglutinative magnetorheological elastomer (MRE) material is presented. MRE structures ranging from a few millimeters down to the micrometer range with highly reproducible results are possible. Semitransparent MREs are also fabricated and their surfaces modified accordingly. This method opens new possibilities for MREs in biomedical engineering and microfluidic applications. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 Y1 - 2013 U6 - https://doi.org/10.1002/app.38500 VL - 128 IS - 4 SP - 2508 EP - 2515 PB - Wiley CY - New York, NY ER - TY - CHAP A1 - Shamonin (Chamonine), Mikhail A1 - Dechant, Eduard A1 - Fedulov, Feodor A1 - Fetisov, Leonid Y. T1 - Bandwidth optimization of piezoelectric cantilever beam arrays for harvesting energy from broadband, low-frequency mechanical vibrations T2 - INTERMATIC 2016, 21.–25.11.2016, Moskau Y1 - 2016 UR - https://elibrary.ru/item.asp?id=29382003 VL - 16 SP - 187 EP - 190 CY - Moskau ER - TY - JOUR A1 - Kurzweil, Peter A1 - Shamonin (Chamonine), Mikhail A1 - Udalzow, Anton T1 - Selbstentladung und Leckstromverhalten elektrochemischer Speicher: Impedanzspektroskopie im Langzeitversuch JF - Forschungsbericht 2016 / OTH Amberg-Weiden N2 - Doppelschichtkondensatoren sind elektrochemische Speicher, die innerhalb von Mikrosekunden auf schnelle Laständerungen antworten. Auf der Basis einer mehr als zehnjährigen Testerfahrung unserer Arbeitsgruppe sind wir in der Lage, das Alterungsverhalten von Superkondensatoren anhand von Kapazitätsverlust, parasitären Nebenreaktionen und der chemischen Analyse von Alterungsprodukten zu quantifizieren. Weitgehend ungeklärt sind die elektrochemischen Mechanismen bei der Selbstentladung der Bauteile, die wir nun mithilfe der Impedanzspektroskopie näher untersucht haben . Double-layer capacitors are electrochemical storage devices that are able to respond to immediate load changes within some microseconds. Based on more than ten years testing experience of our work group, the aging behaviour of supercapacitors is quantified in terms of capacitance loss, parasitic side reactions, and the chemical analysis of decomposition products. So far, the electrochemical processes during self-discharge have been widely unknown. By the help of impedance spectroscopy, we investigated this item in more detail. Y1 - 2016 UR - https://www.oth-aw.de/files/oth-aw/Aktuelles/Veroeffentlichungen/Forschungsbericht/Forschungsbericht_2016.pdf SN - 2365-1997 SP - 90 EP - 94 PB - Ostbayerische Technische Hochschule Amberg-Weiden ER - TY - CHAP A1 - Khaled, W. A1 - Reichling, S. A1 - Bruhns, Otto T. A1 - Ermert, Helmut A1 - Monkman, Gareth J. A1 - Egersdörfer, Stefan A1 - Baumann, Michael A1 - Böse, Holger A1 - Freimuth, Herbert A1 - Tunayar, A. T1 - Palpation imaging using a haptic sensor actuator system for medical applications T2 - Actuator 2004 : 9th International Conference on New Actuators & 3rd International Exhibition on Smart Actuators and Drive Systems, 14-16 June 2004, Bremen, Germany Y1 - 2004 SP - 379 EP - 382 PB - HVG Hanseatische Veranstaltungs-GmbH CY - Bremen ER - TY - JOUR A1 - Monkman, Gareth J. A1 - Boody, F. P. T1 - Ein Vergleich verschiedene Master-Programme JF - Die Neue Hochschule Y1 - 2003 IS - 1 SP - 12 EP - 13 PB - DUZ Verlags- und Medienhaus GmbH CY - Berlin ER - TY - CHAP A1 - Monkman, Gareth J. T1 - Auswirkungen der Mechatronik auf die Entwicklungsmethodik T2 - Mechatronik Forum, OTTI, Handelskammer Regensburg, 25.-26. Oktober 2000 Y1 - 2000 ER - TY - CHAP A1 - Monkman, Gareth J. T1 - Sensors and Actuators in Automation T2 - Ostbayerisches Fachforum für Mechatronik, Roding, 16. März 2001 Y1 - 2001 ER - TY - CHAP A1 - Tunayar, A. A1 - Klein, Dagmar A1 - Freimuth, Herbert A1 - Böse, Holger A1 - Baumann, Michael A1 - Monkman, Gareth J. A1 - Egersdörfer, Stefan A1 - Ermert, Helmut A1 - Khaled, W. T1 - A tactile array based on electrorheological fluids T2 - Actuator 2004 : 9th International Conference on New Actuators & 3rd International Exhibition on Smart Actuators and Drive Systems, 14-16 June 2004, Bremen, Germany Y1 - 2004 SP - 601 EP - 604 PB - HVG Hanseatische Veranstaltungs-GmbH CY - Bremen ER - TY - CHAP A1 - Zappa, O. A1 - Monkman, Gareth J. A1 - Egersdörfer, Stefan A1 - Datzer, G. A1 - Kahled, W. A1 - Böse, Holger A1 - Tunayar, A. T1 - High Voltage Switching using Bulk GaAs T2 - Actuator 2004 : 9th International Conference on New Actuators & 3rd International Exhibition on Smart Actuators and Drive Systems, 14-16 June 2004, Bremen, Germany Y1 - 2004 PB - HVG Hanseatische Veranstaltungs-GmbH CY - Bremen ER - TY - GEN A1 - Monkman, Gareth J. A1 - Sindersberger, Dirk T1 - Investigation of the electrical properties of magneto-active polymers T2 - DFG-Tagung, Benedikbeuern, September 2015 Y1 - 2015 ER - TY - JOUR A1 - Monkman, Gareth J. T1 - Special Issue on Miniature Actuators JF - Mechatronics Y1 - 2000 U6 - https://doi.org/10.1016/S0957-4158(99)00061-6 VL - 10 IS - 4/5 SP - 429 EP - 430 PB - Elsevier ER - TY - JOUR A1 - Monkman, Gareth J. T1 - Electroadhesive Microgrippers JF - Assembly Automation Y1 - 2003 VL - 24 IS - 1 SP - 326 EP - 330 PB - MCB University Press ER - TY - JOUR A1 - Hesmer, Frank A1 - Tatartschuk, Eugen A1 - Zhuromskyy, Oleksandr A1 - Radkovskaya, Anna A. A1 - Shamonin (Chamonine), Mikhail A1 - Hao, Tong A1 - Stevens, Chris J. A1 - Faulkner, Grahame A1 - Edwards, David J. A1 - Shamonina, Ekaterina T1 - Coupling mechanisms for split ring resonators: Theory and experiment JF - Physica status solidi b N2 - We study experimentally and theoretically coupling mechanisms between metamaterial elements of the split ring resonator (SRR) type. We show that, depending on the orientation of the elements relative to each other, the coupling may be either of magnetic or electric type or a combination of both. Experimental results on SRRs with resonances around 1.7–1.9 GHz agree quantitatively with results of simulations (CST Microwave Studio). Further simulations provide analysis for a variety of SRRs both in the GHz and in the 20 THz frequency regions. The variety of coupling mechanisms can be employed in designing near field manipulating devices based on propagation of slow waves. Y1 - 2007 U6 - https://doi.org/10.1002/pssb.200674501 VL - 244 IS - 4 SP - 1170 EP - 1175 PB - Wiley ER - TY - JOUR A1 - Sydoruk, O. A1 - Radkovskaya, Anna A. A1 - Zhuromskyy, Oleksandr A1 - Shamonina, Ekaterina A1 - Shamonin (Chamonine), Mikhail A1 - Stevens, Chris J. A1 - Faulkner, Grahame A1 - Edwards, David J. A1 - Solymar, L. T1 - Tailoring the near-field guiding properties of magnetic metamaterials with two resonant elements per unit cell JF - PHYSICAL REVIEW B N2 - A theoretical and experimental study of magnetic metamaterials with unit cells containing two resonant elements is presented. The properties of these structures, consisting of split rings, are governed by strongly anisotropic magnetic coupling between individual elements. This coupling leads to propagation of slow magnetoinductive waves in the vicinity of the resonant frequency. The wavelength of magnetoinductive waves is much smaller than the free-space wavelength of the electromagnetic radiation. This opens up the possibility of manipulating the near field on a subwavelength scale. We develop a theoretical formulation for coupled chains of metamaterial elements allowing the tailoring of their guiding properties in the near field. In a comprehensive analysis modes of coupled waveguides supporting forward and/or backward waves are identified and the corresponding hybridization mechanisms for dispersion equations of magnetoinductive waves are determined. Analytical predictions are verified both experimentally and numerically on a variety of coupled waveguides. The approach can be employed for the design of near-field manipulating devices. Y1 - 2006 U6 - https://doi.org/10.1103/PhysRevB.73.224406 VL - 73 IS - 22 PB - APS ER - TY - JOUR A1 - Radkovskaya, Anna A. A1 - Shamonin (Chamonine), Mikhail A1 - Stevens, Chris J. A1 - Faulkner, Grahame A1 - Edwards, David J. A1 - Shamonina, Ekaterina A1 - Solymar, L. T1 - An experimental study of the properties of magnetoinductive waves in the presence of retardation JF - Journal of Magnetism and Magnetic Materials N2 - Magnetoinductive (MI) waves owe their existence to the magnetic coupling between metamaterial elements. First experiments confirming the existence of MI waves were carried out on capacitively loaded loops and Swiss Rolls about three orders of magnitude smaller than the operating wavelengths (5–15 m) so that the radiation effects did not play any significant role. In the present paper MI waves are studied experimentally on various types of split ring resonators of about 1 cm diameter operating in the microwave region between 1 and 2 GHz. Our results prove that retardation has a significant effect upon the propagation of MI waves. Y1 - 2006 U6 - https://doi.org/10.1103/physrevb.73.224406 VL - 300 IS - 1 SP - 29 EP - 32 PB - Elsevier ER - TY - JOUR A1 - Radkovskaya, Anna A. A1 - Shamonin (Chamonine), Mikhail A1 - Stevens, Chris J. A1 - Faulkner, Grahame A1 - Edwards, David J. A1 - Shamonina, Ekaterina A1 - Solymar, L. T1 - Resonant frequencies of a combination of split rings: Experimental, analytical and numerical study JF - Microwave and Optical Technoly Letters N2 - The resonant frequencies of five different ring resonators are measured with the aid of a network analyser within the frequency range of about 1.5 to 2.8 GHz. The resonant frequencies for those configurations are also determined from numerical calculations using the commercially available MICRO-STRIPES package. The experimental and numerical results are shown to be very close to each other. Analytical results from various authors, available for three of the configurations, are also compared with the experimental results; one of them leads to a large discrepancy, but the other analytical approximations are shown to be not too far off. Y1 - 2005 U6 - https://doi.org/10.1002/mop.21021 VL - 46 IS - 5 SP - 473 EP - 476 PB - Wiley ER - TY - JOUR A1 - Shamonin (Chamonine), Mikhail A1 - Shamonina, Ekaterina A1 - Kalinin, V. A1 - Solymar, L. T1 - Resonant frequencies of a split-ring resonator: Analytical solutions and numerical simulations JF - Microwave and optical technology letters N2 - A set of differential equations describing the current andvoltage distribution in a split-ring resonator is derived and solved ana-lytically. The resonant frequencies may be obtained from the solution of a characteristic equation. An approximate solution for the lowest reso-nant frequency agrees with that obtained by heuristic arguments. The analytical results are supported by numerical simulations KW - metamaterial KW - split-ring resonator KW - resonant frequencies KW - equivalent distributed circuit KW - characteristic equation Y1 - 2004 U6 - https://doi.org/10.1002/mop.20567 VL - 44 IS - 2 SP - 133 EP - 136 PB - Wiley ER - TY - JOUR A1 - Shamonin (Chamonine), Mikhail A1 - Shamonina, Ekaterina A1 - Kalinin, V. A1 - Solymar, L. T1 - Properties of a metamaterial element: Analytical solutions and numerical simulations for a singly split double ring JF - Journal of Applied Physics N2 - An equivalent circuit, consisting of bulk and distributed elements, is derived for describing the properties of a potential metamaterial element capable of providing negative effective permeability. It is the singly split double ring (SSDR), a special case of the split ring resonator (J. B. Pendry et al., IEEE Trans. Microwave Theory Tech. 47, 2075 (1999)), obtained when the gap capacitance in the inner ring is infinitely large. The variables are the inter-ring voltage and the currents flowing in the inner and outer rings. The excitation is assumed in the form of a spatially constant temporally varying magnetic field. The functions, showing the angular variation of the variables, are found by solving a set of differential equations with boundary conditions imposed at the position of the split. It is shown from the analytical solution that the SSDR can have resonant frequencies in the full spectrum from very low to very high frequencies. It is pointed out in particular that whenever the mean diameter of the ring is equal to an odd multiple of the half wavelength it is always possible to find a set of parameters which will give rise to resonance. As examples the resonant frequencies are determined for eight sets of parameters. Results are also derived by replacing the distributed circuit with a number of discrete circuits. It is finally shown that the results obtained from the equivalent circuit model are in excellent agreement with those derived from the MICRO-STRIPES numerical package which solves Maxwell’s equations in the time domain. Y1 - 2004 U6 - https://doi.org/10.1063/1.1652251 VL - 95 IS - 7 PB - AIP ER - TY - JOUR A1 - Klank, Michael A1 - Hagedorn, Oliver A1 - Holthaus, Carsten A1 - Shamonin (Chamonine), Mikhail A1 - Dötsch, Horst T1 - Characterization and optimization of magnetic garnet films for magneto-optical visualization of magnetic field distributions JF - NDT & E International N2 - Rare-earth iron garnet films with in-plane anisotropy grown on (111)-oriented substrates can be used as magneto-optical indicator films for visualization of magnetic leakage fields in nondestructive evaluation. The influence of Faraday rotation, Faraday ellipticity, absorption and film thickness on the performance of a magneto-optical indicator film is investigated. A new optimization method is introduced and compared with the method of contrast optimization. The theory is experimentally verified and an application example is presented. KW - Magneto-optics KW - Imaging KW - Magnetic flux leakage KW - Garnet films Y1 - 2003 U6 - https://doi.org/10.1016/S0963-8695(03)00012-4 VL - 36 IS - 6 SP - 375 EP - 381 PB - Elsevier ER - TY - JOUR A1 - Apelsmeier, Andreas A1 - Schmauss, Bernhard A1 - Shamonin (Chamonine), Mikhail T1 - Compensation of parasitic losses in an extrinsic fiber-optic temperature sensor based on intensity measurement JF - Sensors and Actuators A: Physical N2 - A method of referencing in an extrinsic optical fiber sensor system utilizing temperature dependence of the absorption edge in a semiconductor crystal (semi-insulating iron-doped indium phosphide) is demonstrated. The intensity reference is provided by controlling the temperature of an LED source and transmission measurements with different emission spectra. A transient operation regime is introduced. The entire process is controlled by a microprocessor unit. The performance of the sensor system is investigated and it is shown that the connector losses may be compensated for. Contrary to the published works performed with GaAs crystals it was not observed that the absorption coefficient of the semiconductor follows the law for idealized direct-gap semiconductor but can be described by the so-called Urbach tail. Since the proposed sensor system comprises a single LED source, simple electronics and no optical fiber couplers it is promising for realization of low-cost fiber-optic temperature sensors, e.g. for power transformer monitoring or magnetic resonance imaging applications. KW - Extrinsic optical fiber sensor KW - Temperature measurement KW - Intensity measurement KW - Intensity referencing KW - Indium phosphide KW - Transient operation Y1 - 2012 U6 - https://doi.org/10.1016/j.sna.2011.10.015 VL - 173 IS - 1 SP - 49 EP - 54 ER - TY - JOUR A1 - Apelsmeier, Andreas A1 - Gleixner, Ramona A1 - Mayer, Matthias A1 - Shamonin (Chamonine), Mikhail A1 - Schmauss, Bernhard T1 - Intensity referencing in an extrinsic optical fiber temperature sensor JF - Procedia Engineering N2 - Optical fiber sensors based on intensity measurement require some form of intensity referencing to avoid errors arising from parasitic losses. Known techniques of referencing such as balanced bridge, divided beam systems or two-wavelength referencing are not suitable for low-cost applications since they use relatively complicated optical components such as multiple LED sources, couplers, filters etc. In this work a novel method of referencing in an extrinsic optical fiber sensor system utilizing temperature dependence of absorption edge in a semiconductor crystal is described. The sensor system comprises a single LED source and no optical fiber junctions. The emission spectrum of an LED depends on its temperature. The reference is provided by controlling the temperature of an LED source and transmission measurements with different emission spectra. The entire process is controlled by a microprocessor unit. Performance of a sensor system is investigated and it is shown that the losses in connectors may be compensated for. KW - Extrinsic optical fiber sensor KW - Intensity referencing KW - Temperature measurement KW - Absorption edge KW - Semiconductor KW - Hot-spot measurement Y1 - 2010 U6 - https://doi.org/10.1016/j.proeng.2010.09.301 VL - 5 SP - 1095 EP - 1098 PB - Elsevier ER - TY - JOUR A1 - Trautner, Ralph A1 - Schmauss, Bernhard A1 - Shamonin (Chamonine), Mikhail T1 - Herstellung und Charakterisierung eines extrinsischen faseroptischen Elementarsensors zur Temperaturmessung JF - tm - Technisches Messen N2 - Es werden Herstellung und Charakterisierung eines faseroptischen Elementarsensors zur Temperaturmessung vorgestellt. Der Sensorkopf in Form eines Prismas aus Indiumphosphid nutzt die Temperaturabhängigkeit der Absorptionskante des Halbleitermaterials. Aufgrund der Abmessungen des Prismas im Grenzbereich von Feinmechanik zu Mikrosystemtechnik ist ein angepasstes Herstellungsverfahren notwendig. T2 - Manufacture and Characterization of an Extrinsic Elementary Fiber-Optical Sensor for Temperature Measurement KW - Extrinsic fiber optic sensor KW - indiumphosphide KW - temperature measurement KW - manufacturing method KW - characterization Y1 - 2008 U6 - https://doi.org/10.1524/teme.2008.0866 VL - 75 IS - 10 PB - De Gruyter ER - TY - JOUR A1 - Kreitmeier, Florian A1 - Chashin, Dmitri V. A1 - Fetisov, Yuri K. A1 - Fetisov, Leonid Y. A1 - Schulz, Irene A1 - Monkman, Gareth J. A1 - Shamonin (Chamonine), Mikhail T1 - Nonlinear Magnetoelectric Response of Planar Ferromagnetic-Piezoelectric Structures to Sub-Millisecond Magnetic Pulses JF - Sensors N2 - The magnetoelectric response of bi- and symmetric trilayer composite structures to pulsed magnetic fields is experimentally investigated in detail. The structures comprise layers of commercially available piezoelectric (lead zirconate titanate) and magnetostrictive (permendur or nickel) materials. The magnetic-field pulses have the form of a half-wave sine function with duration of 450 µs and amplitudes ranging from 500 Oe to 38 kOe. The time dependence of the resulting voltage is presented and explained by theoretical estimations. Appearance of voltage oscillations with frequencies much larger than the reciprocal pulse length is observed for sufficiently large amplitudes (~1-10 kOe) of the magnetic-field pulse. The origin of these oscillations is the excitation of bending and planar acoustic oscillations in the structures. Dependencies of the magnetoelectric voltage coefficient on the excitation frequency and the applied magnetic field are calculated by digital signal processing and compared with those obtained by the method of harmonic field modulation. The results are of interest for developing magnetoelectric sensors of pulsed magnetic fields as well as for rapid characterization of magnetoelectric composite structures. Y1 - 2012 U6 - https://doi.org/10.3390/s121114821 N1 - Corresponding author: Mikhail Shamonin VL - 12 IS - 11 SP - 14821 EP - 14837 PB - MDPI CY - Basel ER - TY - CHAP A1 - Kreitmeier, Florian A1 - Schulz, Irene A1 - Monkman, Gareth J. A1 - Shamonin (Chamonine), Mikhail A1 - Fetisov, Yuri K. A1 - Chashin, Dmitri V. A1 - Fetisov, Leonid Y. T1 - Observation of Nonlinear Magnetoelectric Response to Magnetic Pulses in Layered Magnetostrictive-Piezoelectric Structures N2 - A detailed experimental study of the magnetoelectric response of planar bi- and symmetric trilayer composite structures to magnetic field pulses is reported. The structures consist of layers of commercially available piezoelectric (lead zirconate titanate) and magnetostrictive (permendur or nickel) materials. The magnetic-field pulses have the form of a half-wave sine function with duration of 450 μs and amplitude from 500 Oe up to 38 kOe. The measurement method is explained and the measured time dependence of the resulting voltage is presented. The most interesting case, when pulse amplitudes are sufficiently large (~ 1-10 kOe) and various types of acoustic oscillation with frequencies much larger than the reciprocal pulse length are excited in the structures, is considered. The dependencies of the magnetoelectric voltage coefficient on the excitation frequency and the applied magnetic field are calculated. By digital signal processing the results are compared with those obtained by the method of harmonic field modulation (HFM). The findings are of interest for developing magnetoelectric sensors for pulsed magnetic fields as well as for rapid characterization of magnetoelectric composite structures. T2 - Proceedings of 2012 21st IEEE ISAF held jointly with 11th IEEE ECAPD and IEEE PFM (ISAF/ECAPD/PFM), 9th-13th of July 2012, Aveiro, Portugal KW - composite materials KW - magnetoelectric effect KW - magnetoelectric sensors KW - magnetostriction KW - piezoelectricity KW - magnetic field pulse Y1 - 2012 U6 - https://doi.org/10.1109/ISAF.2012.6297739 PB - IEEE ER - TY - CHAP A1 - Petchartee, Somrak A1 - Monkman, Gareth J. T1 - Contact Classification using Tactile Arrays T2 - 2007 3rd International Conference on Intelligent Sensors, Sensor Networks and Information (ISSNIP), 3, 03.-06.12.2007, Melbourne, VIC, Australia N2 - This paper proposed a contact recognition algorithm capable of determining contact surfaces types by tactile sensor fusion. This algorithm can recognize grasped objects using a 2- fingered robot hand, on which tactile sensors are mounted. Experiments have demonstrated reliable surface classification and accurate transformation independent of object shape and orientation. The contribution of this paper regards the relations between a surface and the points cloud defining it. Particularly, we investigate on the possibility that there is some intrinsic feature of a points cloud under quadric surface, allowing us to discriminate or classify a dataset defining a surface from the acquisition noise. KW - manipulators KW - objec recognition KW - sensor arrays KW - signal classification KW - tactile sensors Y1 - 2007 U6 - https://doi.org/10.1109/ISSNIP.2007.4496848 SP - 227 EP - 232 ER - TY - GEN A1 - Sorokin, Vladislav V. A1 - Stepanov, Gennady V. A1 - Vasiliev, V. G. A1 - Kramarenko, Elena Yu A1 - Mayer, M. A1 - Shamonin (Chamonine), Mikhail A1 - Monkman, Gareth J. T1 - Investigation of Dynamic Modulus and Normal Force of Magnetorheological Elastomers with Soft and Hard Magnetic Fillers T2 - NANO 2014, July 13 – 18, 2014, Moscow ; Section 06 - Polymer, Organic and Other Soft Matter Materials Y1 - 2014 CY - Moscow ER - TY - JOUR A1 - Petchartee, Somrak A1 - Monkman, Gareth J. T1 - Slip Prediction through Tactile Sensing JF - Sensors & Transducers N2 - This paper introduces a new way to predict contact slip using a resistive tactile sensor. The prototype sensor can be used to provide intrinsic information relating to geometrical features situated on the surface of grasped objects. Information along the gripper finger surface is obtained with a measurement resolution dependant on the number of discrete tactile elements. The tactile sensor predicts the partial slip of a tactile surface by sensing micro vibrations in tangential forces which are caused by an expansion of the slip regions within the contact area. The location of the local slip is not specified but its occurrence can be predicted immediately following micro vibration detection. Predictive models have been used to develop a set of rules which predict the slip based on fluctuations in tactile signal data.   Y1 - 2007 UR - https://www.sensorsportal.com/HTML/DIGEST/march_08/Special_Issue_Vol_90/P_SI_48.pdf SN - 1726-5479 VL - 90 IS - Special Issue April 2008 SP - 310 EP - 324 PB - International Frequency Sensor Association, IFSA ER - TY - CHAP A1 - Heckner, T. A1 - Straka, M. A1 - Schubert, A. A1 - Petchartee, Somrak A1 - Monkman, Gareth J. T1 - Entwicklung eines Navigationssystems für autonome mobile Robotersysteme T2 - International Mechatronik Forum, Linz Y1 - 2006 SP - 520 EP - 527 ER - TY - CHAP A1 - Petchartee, Somrak A1 - Monkman, Gareth J. T1 - Pre-slip sensing using tactile sensor T2 - Proceedings / SINTES 13, International Symposium on Systems Theory, Automation, Robotics, Computers, Informatics, Electronics and Instrumentation, October 18 - 20, 2007, Craiova - Romania Y1 - 2007 SP - 279 EP - 284 ER - TY - JOUR A1 - Stoll, Andrea A1 - Mayer, Matthias A1 - Monkman, Gareth J. A1 - Shamonin (Chamonine), Mikhail T1 - Evaluation of highly compliant magneto-active elastomers with colossal magnetorheological response JF - Journal of applied polymer science N2 - Highly compliant elastomers with a shear storage modulus as low as 25 Pa are prepared using commercially available silicone, plasticizer, and tactile mutator silicone additive. They are used as matrix material for magneto-active elastomers (MAEs) with carbonyl iron contents between 0 and 85 wt %. In the absence of an external magnetic field, the storage modulus of MAEs based on two selected mixtures ranges between ~100 Pa and ~2000 Pa. Addition of a mutator to the matrix mixture results in a long post-cure period depending on the curing temperature and the initial mixture. In the presence of a magnetic field, the presented MAEs exhibit a strong magneto-induced change in storage modulus resulting in a colossal magnetorheological effect of >106 % which is ~30 times higher than previously reported values. The results are of interest in applications using such elastomers as cell substrates with magnetically tunable rigidity. Y1 - 2014 U6 - https://doi.org/10.1002/app.39793 SN - 1097-4628 SN - 0021-8995 PB - Wiley CY - New York, NY ER - TY - BOOK A1 - Monkman, Gareth J. A1 - Hesse, Stefan A1 - Steinmann, Ralf A1 - Schunk, Henrik T1 - Robot Grippers N2 - Since robotic prehension is widely used in all sectors of manufacturing industry, this book fills the need for a comprehensive, up-to-date treatment of the topic. As such, this is the first text to address both developers and users, dealing as it does with the function, design and use of industrial robot grippers. The book includes both traditional methods and many more recent developments such as micro grippers for the optolectronics industry. Written by authors from academia, industry and consulting, it begins by covering the four basic categories of robotic prehension before expanding into sections dealing with endeffector design and control, robotic manipulation and kinematics. Later chapters go on to describe how these various gripping techniques can be used for a common industrial aim, with details of related topics such as: kinematics, part separation, sensors, tool excahnge and compliance. The whole is rounded off with specific examples and case studies. With more than 570 figures, this practical book is all set to become the standard for advanced students, researchers and manufacturing engineers, as well as designers and project managers seeking practical descriptions of robot endeffectors and their applications. Y1 - 2006 SN - 9783527406197 U6 - https://doi.org/10.1002/9783527610280 PB - Wiley ER - TY - JOUR A1 - Schreier, Franz A1 - Kohlert, Dieter T1 - Optimized implementations of rational approximations-a case study on the Voigt and complex error function JF - Computer Physics Communications : an international journal for computational physics and physical chemistry N2 - Rational functions are frequently used as efficient yet accurate numerical approximations for real and complex valued special functions. For the complex error function , whose real part is the Voigt function , the rational approximation developed by Hui, Armstrong, and Wray [Rapid computation of the Voigt and complex error functions, J. Quant. Spectrosc. Radiat. Transfer 19 (1978) 509–516] is investigated. Various optimizations for the algorithm are discussed. In many applications, where these functions have to be calculated for a large x grid with constant y, an implementation using real arithmetic and factorization of invariant terms is especially efficient. Y1 - 2008 U6 - https://doi.org/10.1016/j.cpc.2008.04.012 SN - 0010-4655 VL - 179 IS - 7 SP - 457 EP - 465 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Kohlert, Dieter A1 - Schreier, Franz T1 - Line-by-Line Computation of Atmospheric Infrared Spectra With Field Programmable Gate Arrays JF - IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing N2 - Radiative transfer modelling of high resolution infrared (or microwave) spectra still represents a major challenge for the processing of atmospheric remote sensing data despite significant advances in the numerical techniques utilized in line-by-line modelling by, e.g., optimized Voigt function algorithms or multigrid approaches. Special purpose computing hardware such as Field Programmable Gate Arrays (FPGAs) can be used to cope with the dramatic increase of data quality and quantity. Utilizing a highly optimized implementation of an uniform rational function approximation of the Voigt function, the molecular absorption cross section computation-representing the most compute intensive part of radiative transfer codes-has been realized on FPGA. Design and implementation of the FPGA coprocessor is presented along with first performance tests and an outlook for the ongoing further development. Y1 - 2011 U6 - https://doi.org/10.1109/JSTARS.2010.2098395 VL - 4 IS - 3 SP - 701 EP - 709 ER - TY - JOUR A1 - Kohlert, Dieter T1 - The sub-threshold behaviour of the MOS field-effect transistor JF - European Journal of Physics Y1 - 1998 UR - https://www.scopus.com/authid/detail.uri?authorId=6602919972#disabled VL - 19 IS - 2 SP - 125 EP - 131 PB - IOP Science ER - TY - JOUR A1 - Monkman, Gareth J. T1 - Advances in Shape Memory Polymer Actuation JF - Mechatronics N2 - Shape memory materials fulfill an important role in both actuation and mechanical coupling between actuators and associated dynamic systems. The simplest techniques are thermally based and in addition to the more common shape memory alloys there are also shape memory polymers. These have similar characteristics to those of their metallic cousins, but there the relationship stops. The basic physical principles are very different and this paper attempts to outline the current state-of-the-art to those already involved with the technology and perhaps open a fresh chapter in smart materials to those who are new to it. Y1 - 2000 U6 - https://doi.org/10.1016/S0957-4158(99)00068-9 SN - 1873-4006 SN - 0957-4158 VL - 10 IS - 4/5 SP - 489 EP - 498 PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Petchartee, Somrak A1 - Monkman, Gareth J. T1 - Contact Identification using Tactile Arrays T2 - Proceedings of the 7th IEEE International Symposium on Signal Processing and Information Technology (ISSPIT 2007), 15.-18.12.2007, Giza, Egypt N2 - The proposed method allows a robot to quantify tactile recognition of grasped objects. The responses by the robot are matched by randomly introducing objects following the completion of tactile sensor based training phases on 4 specific objects. The reproduction of the robotic contact identification is accomplished by matching threshold values of the smallest eigenvalue of the Quadric surface - called the eigenvalue trajectory. Once the grasped objects are introduced to the 2-fingered robot hand, the eigenvalue trajectory of contact surfaces are calculated by the system. Calculations are based on the degree of similarity of the characteristics between the newly received and previously trained tactile data. Experimental results indicate that the proposed algorithm allows a successful quantification of robotic contact recognition and the accomplishment of high levels of accuracy in contact identification. These results confirm that the proposed method is useful for identifying contact surfaces based on tactile sensor data. KW - Touch recognition KW - contact classification KW - tactile sensor Y1 - 2007 U6 - https://doi.org/10.1109/ISSPIT.2007.4458144 SP - 1121 EP - 1126 PB - IEEE ER - TY - JOUR A1 - Monkman, Gareth J. T1 - Precise Piezoelectric Prehension JF - Industrial Robot N2 - Piezoelectric actuators are well established for use in expensive optical equipment. Within the last decade, relatively inexpensive piezoelectric actuators have become established technology in pneumatic switching and the first piezoelectrically driven impactive robot grippers are just starting to emerge. Although this article concentrates largely on the use of piezoelectric actuators for use in robot gripping systems, the potential for applications outside this field is immense. KW - Piezoelectric actuators KW - Robots KW - Grippers KW - Nanotechnology Y1 - 2000 U6 - https://doi.org/10.1108/01439910010371605 SN - 0143-991x VL - 27 IS - 3 SP - 189 EP - 194 PB - MCB University Press ER - TY - JOUR A1 - Monkman, Gareth J. T1 - Workpiece Retention during Machine Processing JF - Assembly Automation N2 - Discusses the failings of conventional fixturing systems such as jigs and clamps and describes how electrorheological fluids can be used for flexible fixturing and workpiece retention. KW - Grippers KW - Rheology Y1 - 2001 U6 - https://doi.org/10.1108/01445150110381754 SN - 1758-4078 SN - 0144-5154 VL - 21 IS - 1 SP - 61 EP - 67 PB - Emerald CY - Bringley ER - TY - JOUR A1 - Kral, Christian A1 - Haumer, Anton A1 - Lee, Sang Bin T1 - A Practical Thermal Model for the Estimation of Permanent Magnet and Stator Winding Temperatures JF - IEEE Transactions on Power Electronics N2 - A thermal model for the determination of the temperatures of interior permanent magnets and stator windings is presented in this paper. The innovation of the model relies on one temperature sensor being located in the stator core of the machine. Such sensor is simple to implement in many applications such as traction or EV, where reliability is critical. The estimated stator winding and permanent magnet temperatures are determined by a simplified thermal lumped element network model with only two time constants. It is shown that the proposed thermal model is very robust due to the structure of the model and the measured stator core temperature. The distortion of the temperature estimates caused by the cooling circuit is inherently accounted for such that the model can be used for robust online prediction of temperatures. Experimental results based on a forced water-cooled interior permanent magnet synchronous machine setup are presented to validate the effectiveness of the presented model. KW - cooling KW - lumped element thermal equivalent circuit model KW - magnetic cores KW - permanent magnet machines KW - permanent magnet synchronous machine KW - stators KW - synchronous machines KW - temperature estimation KW - variable speed KW - dynamic load Y1 - 2014 U6 - https://doi.org/10.1109/TPEL.2013.2253128 SN - 1941-0107 SN - 0885-8993 VL - 29 IS - 1 SP - 455 EP - 464 PB - IEEE ER - TY - JOUR A1 - Mayer, Matthias A1 - Rabindranath, Raman A1 - Börner, Juliane A1 - Hörner, Eva A1 - Bentz, Alexander A1 - Salgado, Josefina A1 - Han, Hong A1 - Böse, Holger A1 - Probst, Jörn A1 - Shamonin (Chamonine), Mikhail A1 - Monkman, Gareth J. A1 - Schlunck, Günther T1 - Ultra-Soft PDMS-Based Magnetoactive Elastomers as Dynamic Cell Culture Substrata JF - PLoS ONE N2 - Mechanical cues such as extracellular matrix stiffness and movement have a major impact on cell differentiation and function. To replicate these biological features in vitro, soft substrata with tunable elasticity and the possibility for controlled surface translocation are desirable. Here we report on the use of ultra-soft (Young’s modulus <100 kPa) PDMS-based magnetoactive elastomers (MAE) as suitable cell culture substrata. Soft non-viscous PDMS (<18 kPa) is produced using a modified extended crosslinker. MAEs are generated by embedding magnetic microparticles into a soft PDMS matrix. Both substrata yield an elasticity-dependent (14 vs. 100 kPa) modulation of α-smooth muscle actin expression in primary human fibroblasts. To allow for static or dynamic control of MAE material properties, we devise low magnetic field (≈40 mT) stimulation systems compatible with cell-culture environments. Magnetic field-instigated stiffening (14 to 200 kPa) of soft MAE enhances the spreading of primary human fibroblasts and decreases PAX-7 transcription in human mesenchymal stem cells. Pulsatile MAE movements are generated using oscillating magnetic fields and are well tolerated by adherent human fibroblasts. This MAE system provides spatial and temporal control of substratum material characteristics and permits novel designs when used as dynamic cell culture substrata or cell culture-coated actuator in tissue engineering applications or biomedical devices. Y1 - 2013 U6 - https://doi.org/10.1371/journal.pone.0076196 VL - 8 IS - 10 PB - PLOS ER - TY - CHAP A1 - Khaled, W. A1 - Bruhns, Otto T. A1 - Reichling, S. A1 - Böse, Holger A1 - Baumann, Michael A1 - Monkman, Gareth J. A1 - Egersdörfer, Stefan A1 - Meier, Alexander A1 - Klein, Dagmar A1 - Freimuth, Herbert A1 - Ermert, Helmut T1 - A haptic system for virtual reality applications based on ultrasound elastography and electrorheological fluids T2 - Acoustical Imaging (ACIM) N2 - Mechanical properties of biological tissue represent important diagnostic information and are of histological and pathological relevance. Malignant tumors are significantly stiffer and more immobile than surrounding healthy tissue. Hard calcifications in vessels occur due to arteriosclerosis. The problem is, that such information is usually not available or can only be obtained by manual palpation, which is subjective and limited in sensitivity. It requires intuitive assessment and does not allow quantitative documentation. Unfortunately, none of the established medical imaging equipment such as magnetic resonance imaging (MRI) or X-ray computed tomography (CT) can provide direct measure of tissue elasticity. On the one hand a suitable sensor is required for quantitative measurement of mechanical tissue properties. On the other hand there is also some need for a realistic haptic display of such tissue properties. Suitable actuator arrays with high spatial resolution acting in real time are required. A haptic sensor actuator system is presented in this paper including a sensitive sensor part and an actuator array for different applications. The mechanical consistency of an object is to be locally specified using a sensor system and represented perceptibly in a remote position on an actuator system for the user. The sensor system uses ultrasound (US) elastography, whereas the actuator array is based on electrorheological (ER) fluids. KW - Minimal Invasive Surgery KW - Manual Palpation KW - Tactile Display KW - Virtual Reality Application KW - Ultrasound ELASTOGRAPHY Y1 - 2004 SN - 978-90-481-6652-7 SN - 978-1-4020-2402-3 U6 - https://doi.org/10.1007/978-1-4020-2402-3_85 SN - 0270-5117 SN - 2215-1869 VL - 27 SP - 667 EP - 674 PB - Springer CY - Dordrecht ER - TY - JOUR A1 - Petchartee, Somrak A1 - Monkman, Gareth J. T1 - Optimisation of Prehension Force through Tactile Sensing JF - Industrial Robot N2 - Purpose The purpose of this paper is to analyze surface deformations caused by shear and moment forces on tactile materials and present a method to detect and reduce the risk of slippage by controlling the normal force as measured by tactile sensor arrays. Design/methodology/approach A predictive model has been proposed which uses a basic method adapted to real applications in grasp optimization. Prevention of premature release with minimum prehension force is addressed without the need to measure the coefficient of friction between object and robot gripper. Predictive models have been used to develop a set of rules which predict the pre‐slip based on fluctuations in tactile signal data. Findings The tactile sensors can be used in a “nonlinear” manner during manipulation tasks. When the gripper finger first makes contact with an object, the stress distribution under the finger skin varies rapidly. Predictive models have been used to develop a set of rules which predict the pre‐slip based on fluctuations in tactile signal data. Pre‐slip at the contact area just prior to object movement produces rapid but detectable stress transients. Originality/value Tactile sensors do not measure stress generated by a contact with an object directly, but instead measure strain in an interposed compliant, polymeric medium intended for sensor protection and prehension assistance. Reliable detection of pre‐slip has hitherto eluded researchers using such tactile techniques. KW - Sensors KW - Tactile sensors Y1 - 2008 U6 - https://doi.org/10.1108/01439910810876454 VL - 35 IS - 4 SP - 361 EP - 368 PB - MCB Univ. Press CY - Bradford ER - TY - JOUR A1 - Füchtmeier, Bernd A1 - Egersdoerfer, Stefan A1 - Mai, Ronny A1 - Hente, Rainer A1 - Dragoi, Daniel A1 - Monkman, Gareth J. A1 - Nerlich, Michael T1 - Reduction of femoral shaft fractures in vitro by a new developed reduction robot system "RepoRobo" JF - Injury N2 - Closed reduction of the long bones is associated with the use of considerable force. This force must be maintained for the reduction maneuver and fixation process. At present, apart from the extension table or the large AO distractor, only rather inadequate reduction aids are available. A solution to this problem is being sought in the form of a robotic system with which precision can be improved and the holding effort reduced. In the research project presented here, a synthetic femur with integrated tensioned mainspring and a 32-A3 type fracture served as a bone reduction model. The fracture was stabilized with a standard AO fixator. A Stäubli robot (model RX130) was converted by appropriate modification so that it could be used for the reduction of femoral shaft fractures in vitro. The robot was equipped with a pneumatic 2-fingered gripper, on which the fingers have been modified so that they can grip the AO fixator clamp. A Force-Feedback-Sensor was inserted between the gripper and the robot to obtain online recordings of the forces and moments in all three axes. With this setup it is possible to achieve precise reduction of the fracture in all planes under visual control. KW - Fracture reduction KW - reduction robot KW - RepoRobo Y1 - 2004 U6 - https://doi.org/10.1016/j.injury.2004.05.019 SN - 1879-0267 SN - 0020-1383 VL - 35 IS - 1, Supplement SP - 113 EP - 119 PB - Elsevier ER - TY - CHAP A1 - Petchartee, Somrak A1 - Monkman, Gareth J. A1 - Suebsromran, Anan ED - Mukhopadhyay, S.C. ED - Gupta, G.S. T1 - 3D-Shape Recognition based Tactile Sensor T2 - Smart Sensors and Sensing Technology N2 - A surface recognition algorithm capable of determining contact surfaces types by means of tactile sensor fusion is proposed. The authors present a recognition processes for 3-dimensional deformations in a 2-dimensional parametric domain. Tactile information is extracted by physical contact with a grasped object through a sensing medium. Information is obtained directly at the interface between the object and the sensing device and relates to three-dimensional position and orientation of the object in the presence of noise. The technique called “eigenvalue trajectory analysis”, is introduced and adopted for specifying the margin of classification and classification thresholds. The authors demonstrate mathematically that this approach, which complements existing work, offers significant computational advantages when applied to challenging contact scenarios such as dynamic recognition of contact deformations. Y1 - 2008 SN - 978-3-540-79589-6 SN - 978-3-540-79590-2 U6 - https://doi.org/10.1007/978-3-540-79590-2_21 SP - 317 EP - 332 PB - Springer CY - Berlin ; Heidelberg ER - TY - CHAP A1 - Kral, Christian A1 - Haumer, Anton A1 - Wöhrnschimmel, Reinhard T1 - Extension of the FundamentalWave Library towards Multi Phase Electric Machine Models T2 - Proceedings of the 10th International Modelica Conference, March 10-12, 2014, Lund, Sweden N2 - Abstract Electric machine theory and electric machine simulations models are often limited to three phases. Up to the Modelica Standard Libray (MSL) version 3.2 the provided machine models were limited to three phases. Particularly for large industrial drives and for redundancy reasons in electric vehicles and aircrafts multi phase electric machines are demanded. In the MSL 3.2.1 an extension of the existing FundamentalWave library has been performed to cope with phase numbers greater than or equal to three. The developed machine models are fully incorporating the multi phase electric; magnetic; rotational and thermal domain. In this publication the theoretical background of the machines models; Modelica implementation details; the parametrization of the models and simulation examples are presented. KW - electric Machine models KW - induction machine KW - Modelica Standard Library KW - multi phase KW - synchronous machine KW - synchronous reluctance machine Y1 - 2014 SN - 978-91-7519-380-9 U6 - https://doi.org/10.3384/ecp14096135 SN - 1650-3686 SN - 1650-3740 SP - 135 EP - 143 PB - Linköping University Electronic Press ER - TY - CHAP A1 - Khaled, W. A1 - Reichling, S. A1 - Bruhns, Otto T. A1 - Monkman, Gareth J. A1 - Egersdörfer, Stefan A1 - Baumann, Michael A1 - Böse, Holger A1 - Klein, Dagmar A1 - Freimuth, Herbert A1 - Tunayar, A. A1 - Lorenz, A. A1 - Pessavento, A. A1 - Ermert, Helmut T1 - Palpation imaging using a haptic system for virtual reality applications in medicine T2 - Perspective in image-guided surgery : proceedings of the Scientific Workshop on Medical Robotics, Navigation, and Visualization : RheinAhrCampus Remagen, Germany, 11-12 March Y1 - 2004 SP - 407 EP - 414 PB - World Scientific Publ. CY - Singapore ER - TY - CHAP A1 - Khaled, W. A1 - Reichling, S. A1 - Bruhns, Otto T. A1 - Monkman, Gareth J. A1 - Egersdörfer, Stefan A1 - Baumann, Michael A1 - Böse, Holger A1 - Klein, Dagmar A1 - Freimuth, Herbert A1 - Tunayar, A. A1 - Lorenz, A. A1 - Pessavento, A. A1 - Ermert, Helmut T1 - Palpation Imaging using a Haptic System for Virtual Reality Applications in Medicine T2 - Proceedings of the 12th Annual Medicine Meets Virtual Reality Conference: - Building a Better You: The Next Tools for Medical Education, Diagnosis, and Care. - Medicine Meets Virtual Reality (MMVR) - Newport Beach (California, USA). 2004 Y1 - 2004 ER - TY - CHAP A1 - Egersdörfer, Stefan A1 - Schumm, M. A1 - Kessler, C. A1 - Monkman, Gareth J. A1 - Böse, Holger T1 - Smart Fluids für die Schnittstelle Mensch-Maschine der Zukunft T2 - International Mechatronik Forum, Linz Y1 - 2006 SP - 421 EP - 428 ER - TY - JOUR A1 - Böse, Holger A1 - Baumann, Michael A1 - Monkman, Gareth J. A1 - Egersdörfer, Stefan A1 - Tunayar, A. A1 - Freimuth, Herbert A1 - Ermert, Helmut A1 - Khaled, W. T1 - A new ER fluid based haptic actuator system for virtual reality JF - International journal of modern physics / B Condensed matter physics, statistical physics N2 - The concept and some steps in the development of a new actuator system which enables the haptic perception of mechanically inhomogeneous virtual objects are introduced. The system consists of a two-dimensional planar array of actuator elements containing an electrorheological (ER) fluid. When a user presses his fingers onto the surface of the actuator array, he perceives locally variable resistance forces generated by vertical pistons which slide in the ER fluid through the gaps between electrode pairs. The voltage in each actuator element can be individually controlled by a novel sophisticated switching technology based on optoelectric gallium arsenide elements. The haptic information which is represented at the actuator array can be transferred from a corresponding sensor system based on ultrasonic elastography. The combined sensor-actuator system may serve as a technology platform for various applications in virtual reality, like telemedicine where the information on the consistency of tissue of a real patient is detected by the sensor part and recorded by the actuator part at a remote location. Y1 - 2005 U6 - https://doi.org/10.1142/9789812702197_0129 [Titel anhand dieser DOI in Citavi-Projekt übernehmen] VL - 19 IS - 7-9 SP - 1628 EP - 1634 PB - World Scientific Publ. ER - TY - JOUR A1 - Monkman, Gareth J. A1 - Egersdörfer, Stefan A1 - Meier, Alexander A1 - Böse, Holger A1 - Baumann, Michael A1 - Ermert, Helmut A1 - Kahled, W. A1 - Freimuth, Herbert T1 - Technologies for Haptic Displays in Teleoperation JF - Industrial Robot N2 - Since the 1960s many alphanumeric to tactile data conversion methods have been investigated, mainly with the ultimate aim of assisting the blind. More recently, interest has been directed toward the display of pictures on haptically explorable surfaces – tactile imaging – for a range of medical, remote sensing and entertainment purposes. This paper examines the technologies which have been utilised for haptically explorable tactile displays over the past three decades, focussing on those which appear commercially viable in the immediate future. Y1 - 2003 U6 - https://doi.org/10.1108/01439910310506792 SN - 0143-991x VL - 30 IS - 6 SP - 525 EP - 530 PB - Emerald ER - TY - CHAP A1 - Egersdörfer, Stefan A1 - Zeidler, A. A1 - Wieser, A. A1 - Trompier, F. A1 - Monkman, Gareth J. A1 - Shamonin (Chamonine), Mikhail T1 - A portable accident dosimeter using tooth enamel T2 - Proceedings of the 7th International Symposium on EPR Dosimetry and Applications and the 2nd International Conference on Biodosimetry held at the Uniformed Services University of the Health Sciences, Bethesda, MD, USA, 10-13 July 2006 Y1 - 2006 PB - Pergamon CY - Oxford ER - TY - GEN A1 - Heckner, T. A1 - Kessler, C. A1 - Egersdörfer, Stefan A1 - Monkman, Gareth J. T1 - Computer based platform for tactile actuator analysis T2 - Actuator 2006 : 10th International Conference on New Actuators and 4th International Exhibition on Smart Actuators and Drive Systems, Bremen, Germany, 14 - 16 June 2006 Y1 - 2006 PB - HVG Hanseatische Veranst.-GmbH ER - TY - JOUR A1 - Klein, Dagmar A1 - Rensink, D. A1 - Freimuth, Herbert A1 - Monkman, Gareth J. A1 - Egersdörfer, Stefan A1 - Böse, Holger A1 - Baumann, Michael T1 - Modelling the Response of a Tactile Array using an Electrorheological Fluids JF - Journal of Physics D: Applied Physics N2 - This paper reports the first step in the development of a tactile array suitable for the presentation of haptic information in virtual reality. The system is based on the electric field dependence of the viscosity of electrorheological fluids. The simulation, as well as the experimental realization of single tactels is described. The mathematical approach is based on the Eckart model (Eckart W 2000 Continuum Mech. Thermodyn. 12 341–62) and its validity is demonstrated by comparing the resulting yield stress with the experimental results from Wunderlich (2000 Dissertation Universität Erlangen-Nürnberg). Two different tactel designs are realized and the experimental results are compared with numerical simulation. The design of modification B is shown to be applicable for the realization of an actuator array with high spatial resolution. Y1 - 2004 U6 - https://doi.org/10.1088/0022-3727/37/5/023 SN - 1361-6463 SN - 0022-3727 VL - 37 IS - 5 SP - 794 EP - 803 PB - IOP Publ. CY - Bristol ER - TY - RPRT A1 - Rabindranath, R. A1 - Böse, Holger A1 - Probst, Jörn A1 - Schlunck, G. A1 - Mayer, Matthias A1 - Forster, Eva A1 - Bentz, Alexander A1 - Shamonin (Chamonine), Mikhail A1 - Monkman, Gareth J. T1 - EAP mit magnetisch steuerbarer Elastizität zur Interaktion mit Bindegewebszellen MagElan BT - Teilvorhaben (HS-Regensburg) "Etablierung eines mechatronischen Systems zur (Magneto) Elastophorese von Bindegewebszellen" ; Schlussbericht ; Verbundprojekt "MagElan" ; Laufzeit des Vorhabens: 01.07.2009 - 30.10.2011 Y1 - 2012 N1 - Förderkennzeichen BMBF 13N10574 CY - Regensburg ER - TY - CHAP A1 - Böse, Holger A1 - Ermert, Helmut A1 - Tunayar, A. A1 - Monkman, Gareth J. A1 - Baumann, Michael A1 - Kahled, W. A1 - Reichling, S. A1 - Bruhns, Otto T. A1 - Freimuth, Herbert A1 - Egersdörfer, Stefan T1 - A Novel Haptic Sensor-Actuator System for Applications in Virtual Reality T2 - BMBF-Tagung, Leipzig 19.10 February 2004 Y1 - 2004 ER - TY - JOUR A1 - Klein, Dagmar A1 - Freimuth, Herbert A1 - Monkman, Gareth J. A1 - Egersdörfer, Stefan A1 - Meier, Alexander A1 - Böse, Holger A1 - Baumann, Michael A1 - Ermert, Helmut A1 - Bruhns, Otto T. T1 - Electrorheological Tactile Elements JF - Mechatronics N2 - The use of ultrasound systems for medical examination and diagnosis is nothing new. The extension of ultrasound techniques for real time elastographic analysis purposes represents a more recent development. Nevertheless, as they stand all such techniques rely on the interpretation of two-dimensional visual data displayed on a video screen. In reality however, a medical doctor will make as much use of exploratory touch as he or she does vision, making the simultaneous portrayal of both video and tactile information most desirable [Böse H, Monkman GJ, Freimuth H, Ermert H. Haptisches Sensor-Aktor-System uaf der grundlage der Echtzeitelastographie sowie von elktro- und magnetorheologischen Materialien “HASASEM” [3]. BMBF Antrag 01 IR A14D, Oktober 2000]. This paper discusses the preliminary tests and basic design parameters for single tactels using electrorheological fluids. The final aim is to produce a prototype three-dimensional tactile display comprising electrically switchable micro-machined cells whose mechanical moduli are governed by phase changes experienced by electrorheological fluids. This will be integrated with the latest elastographic ultrasonic sensor systems in order to present the human fingers with controllable surfaces capable of emulating biological tissue, muscle and bone. Y1 - 2005 U6 - https://doi.org/10.1016/j.mechatronics.2004.05.007 VL - 15 IS - 7 SP - 883 EP - 897 PB - Pergamon CY - Oxford ER - TY - CHAP A1 - Kahled, W. A1 - Reichling, S. A1 - Bruhns, Otto T. A1 - Böse, Holger A1 - Baumann, Michael A1 - Egersdörfer, Stefan A1 - Klein, Dagmar A1 - Tunayer, A. A1 - Freimuth, Herbert A1 - Lorenz, A. A1 - Pessavento, A. A1 - Ermert, Helmut ED - Westwood, James D. ED - Haluck, Randy S. T1 - Palpation Imaging using a Haptic System for Virtual Reality applications in Medicine T2 - Medicine meets virtual reality 12 Y1 - 2004 SP - 147 EP - 153 PB - IOS Press ER - TY - CHAP A1 - Böse, Holger A1 - Ermert, Helmut A1 - Tunayar, A. A1 - Monkman, Gareth J. A1 - Baumann, Michael A1 - Kahled, W. A1 - Reichling, S. A1 - Bruhns, Otto T. A1 - Freimuth, Herbert A1 - Egersdörfer, Stefan T1 - A novel haptic sensor-actuator system for virtual reality T2 - Eurohaptics 2004, Munich, Germany, June 5 - 7, 2004 Proceedings of the 4th International Conference EuroHaptics 2004 ; June 5 - 7, 2004, München, Germany Y1 - 2004 SN - 3-9809614-0-0 PB - Inst. of Automatic Control Engineering CY - München ER - TY - JOUR A1 - Böse, Holger A1 - Monkman, Gareth J. A1 - Freimuth, Herbert A1 - Tunayar, A. A1 - Khaled, W. A1 - Baumann, Michael A1 - Egersdörfer, Stefan A1 - Ermert, Helmut T1 - A new haptic sensor-actuator system based on electrorheological fluids JF - Actuator 2004 : 9th International Conference on New Actuators & 3rd International Exhibition on Smart Actuators and Drive Systems ; Bremen, Germany, 14 - 16 June 2004 Y1 - 2004 PB - HVG Hanseatische Veranstaltungs-GmbH CY - Bremen ER - TY - CHAP A1 - Böse, Holger A1 - Monkman, Gareth J. A1 - Freimuth, Herbert A1 - Klein, Dagmar A1 - Ermert, Helmut A1 - Baumann, Michael A1 - Egersdörfer, Stefan A1 - Bruhns, Otto T. T1 - ER Fluid Based Haptic System for Virtual Reality T2 - Actuator 2002 : 8th International Conference on New Actuators & 2nd International Exhibition on Smart Actuators and Drive Systems ; Bremen, Germany, 10 - 12 June 2002 Y1 - 2002 SP - 351 EP - 354 ET - CD-ROM ER - TY - CHAP A1 - Khaled, W. A1 - Bruhns, Otto T. A1 - Reichling, S. A1 - Böse, Holger A1 - Baumann, Michael A1 - Monkman, Gareth J. A1 - Egersdörfer, Stefan A1 - Meier, Alexander A1 - Klein, Dagmar A1 - Freimuth, Herbert A1 - Ermert, Helmut T1 - A haptic sensor-actuator-system based on ultrasound elastography and electrorheological fluids for virtual reality applications in medicine T2 - CARS 2003 : computer assisted radiology and surgery ; proceedings of the 17th International Congress and Exhibition London, June 25 - 28, 2003 N2 - Mechanical properties of biological tissue represent important diagnostic information and are of histological relevance (hard lesions, "nodes" in organs: tumors; calcifications in vessels: arteriosclerosis). The problem is, that such information is usually obtained by digital palpation only, which is limited with respect to sensitivity. It requires intuitive assessment and does not allow quantitative documentation. A suitable sensor is required for quantitative detection of mechanical tissue properties. On the other hand, there is also some need for a realistic mechanical display of those tissue properties. Suitable actuator arrays with high spatial resolution and real-time capabilities are required operating in a haptic sensor actuator system with different applications. The sensor system uses real time ultrasonic elastography whereas the tactile actuator is based on electrorheological fluids. Due to their small size the actuator array elements have to be manufactured by micro-mechanical production methods. In order to supply the actuator elements with individual high voltages a sophisticated switching and control concept have been designed. This haptic system has the potential of inducing real time substantial forces, using a compact lightweight mechanism which can be applied to numerous areas including intraoperative navigation, telemedicine, teaching, space and telecommunication. Y1 - 2003 SP - 1354 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Hirmer, Marion A1 - Danilov, Sergey N. A1 - Giglberger, Stephan A1 - Putzger, Jürgen A1 - Niklas, Andreas A1 - Jäger, Andreas A1 - Hiller, Karl-Anton A1 - Schmalz, Gottfried A1 - Redlich, Britta A1 - Schulz, Irene A1 - Monkman, Gareth J. A1 - Ganichev, Sergey D. T1 - Spectroscopic Study of Human Teeth and Blood from Visible to Terahertz Frequencies for Clinical Diagnosis of Dental Pulp Vitality JF - Journal of Infrared, Millimeter, and Terahertz Waves N2 - Transmission spectra of wet human teeth and dentin slices, together with blood of different flow rates were investigated. The measurements carried out over a wide spectral range, from visible light down to terahertz radiation. The results make it possible to find the optimum light frequency for an all-optical determination of pulpal blood flow and, consequently, for clinically diagnosis of tooth vitality. KW - Infrared and terahertz transmission KW - Dentin KW - Lentic or flowing blood KW - Dental pulp vitality Y1 - 2012 U6 - https://doi.org/10.1007/s10762-012-9872-3 SN - 1866-6906 VL - 33 SP - 366 EP - 375 PB - Springer ER - TY - GEN A1 - Hesse, Stefan A1 - Monkman, Gareth J. A1 - Steinmann, Ralf A1 - Schunk, Henrik T1 - Robotergreifer BT - Funktion, Gestaltung und Anwendung industrieller Greiftechnik Y1 - 2004 SN - 978-3-446-22920-4 SN - 3-446-22920-5 PB - Hanser CY - München ; Wien ER - TY - JOUR A1 - Khaled, W. A1 - Ermert, Helmut A1 - Bruhns, Otto T. A1 - Reichling, S. A1 - Böse, Holger A1 - Baumann, Michael A1 - Monkman, Gareth J. A1 - Egersdörfer, Stefan A1 - Meier, Alexander A1 - Klein, Dagmar A1 - Freimuth, Herbert T1 - Haptic sensor-actuator-system based on ultrasound elastography and electrorheological fluids for virtual reality applications in medicine JF - Studies in health technology and informatics, Medicine Meets Virtual Reality (MMVR) N2 - Mechanical properties of biological tissue represent important diagnostic information and are of histological relevance (hard lesions, "nodes" in organs: tumors; calcifications in vessels: arteriosclerosis). The problem is, that such information is usually obtained by digital palpation only, which is limited with respect to sensitivity. It requires intuitive assessment and does not allow quantitative documentation. A suitable sensor is required for quantitative detection of mechanical tissue properties. On the other hand, there is also some need for a realistic mechanical display of those tissue properties. Suitable actuator arrays with high spatial resolution and real-time capabilities are required operating in a haptic sensor actuator system with different applications. The sensor system uses real time ultrasonic elastography whereas the tactile actuator is based on electrorheological fluids. Due to their small size the actuator array elements have to be manufactured by micro-mechanical production methods. In order to supply the actuator elements with individual high voltages a sophisticated switching and control concept have been designed. This haptic system has the potential of inducing real time substantial forces, using a compact lightweight mechanism which can be applied to numerous areas including intraoperative navigation, telemedicine, teaching, space and telecommunication. Y1 - 2003 VL - 11 IS - 94 SP - 144 EP - 150 PB - IOS Press ER - TY - CHAP A1 - Strobl, Marius A1 - Kucera, Markus A1 - Foeldi, Andrei A1 - Balbierer, Norbert A1 - Hilbert, Carolin A1 - Waas, Thomas T1 - Towards automotive virtualization T2 - 2013 International Conference on Applied Electronics (AE) : 10 - 12 Sept. 2013, Pilsen, Czech Republic N2 - Virtualization has come a long way since its beginnings in the 1960s. Nowadays, Virtual Machine Monitor (VMM) - or hypervisor-based virtualization of servers is the de facto standard in data centers and a building block of the cloud hype. In recent years, virtualization has also been adopted to embedded devices such as avionics systems and mobile phones. The first mass deployment of embedded virtualization can probably be seen in video game consoles, though. However, it is still not employed by automotive electronics. This is despite the fact that with the upcoming domain controller architecture, virtualization can yield benefits beyond a mere consolidation of a multitude of Electronic Control Units (ECUs) into a few Domain Controller Units (DCUs). This paper presents merits of automotive virtualization, especially as a foundation for DCUs. Y1 - 2013 UR - https://ieeexplore.ieee.org/document/6636534/authors#authors SP - 291 EP - 296 PB - IEEE CY - Piscataway, NJ ER - TY - CHAP A1 - Khaled, W. A1 - Bruhns, Otto T. A1 - Reichling, S. A1 - Böse, Holger A1 - Baumann, Michael A1 - Monkman, Gareth J. A1 - Egersdörfer, Stefan A1 - Meier, Alexander A1 - Freimuth, Herbert A1 - Tunayar, A. A1 - Ermert, Helmut T1 - A New Haptic Sensor Actuator System for Virtual Reality Applications in Medicine T2 - Medical Image Computing and Computer-Assisted Intervention - MICCAI 2003: 6th International Conference, Montréal, Canada, November 15-18, 2003, Proceedings Y1 - 2003 SN - 978-3540204626 SP - 132 EP - 140 PB - Springer ER - TY - CHAP A1 - Petchartee, Somrak A1 - Monkman, Gareth J. T1 - 3D-Shape Recognition based Tactile Sensor T2 - ICST 2007, Proceedings of 2nd International Conference on Sensing Technology : Massey University, Palmerston North, New Zealand, November 26 - 28, 2007 Y1 - 2007 SP - 56 EP - 61 PB - Inst. of Information Sciences and Techn., Massey Univ. CY - Palmerston ER - TY - JOUR A1 - Petchartee, Somrak A1 - Monkman, Gareth J. T1 - Contact Recognition through Tactile Sensing JF - ACTA Universitatis Apulensis; Seria Mathematics-Informatics Y1 - 2007 SN - 1582-5329 PB - Department of Mathematics and Informatics CY - Alba Iulia ER - TY - CHAP A1 - Schumm, M. A1 - Schwarz, E. A1 - Wahler, D. A1 - Jayaprakash, S. N. A1 - Monkman, Gareth J. T1 - The Trilopede T2 - Informatics Microsystems Information Systems Preceedings Y1 - 2012 VL - 1 IS - 1 PB - Moscow State Technical University ER - TY - CHAP A1 - Böse, Holger A1 - Monkman, Gareth J. A1 - Freimuth, Herbert A1 - Tunayar, A. A1 - Ermert, Helmut A1 - Khaled, W. A1 - Baumann, Michael A1 - Egersdörfer, Stefan T1 - A new ER fluid based haptic actuator system for virtual reality T2 - Proceedings of the Ninth International Conference Electrorheological Fluids and Magnetorheological Suspensions (ERMR 2004) : Beijing, China, 29 August - 3 September 2004 Y1 - 2004 SP - 889 EP - 895 PB - World Scientific CY - Singapore ER - TY - CHAP A1 - Petchartee, Somrak A1 - Monkman, Gareth J. T1 - Contact classification using tactile arrays T2 - Proc. International Conference on Engineering & ICT 2007 (ICEI 2007), 27th to 29th November 2007, Malacca, Malaysia Y1 - 2007 ER - TY - JOUR A1 - Stadler, Dominik A1 - Hofmann, Matthias J. A1 - Motschmann, Hubert A1 - Shamonin (Chamonine), Mikhail T1 - Automotived system for measuring the surface dilational modulus of liquid-air interfaces JF - Measurement Science and Technology N2 - The surface dilational modulus is a crucial parameter for describing the rheological properties of aqueous surfactant solutions. These properties are important for many technological processes. The present paper describes a fully automated instrument based on the oscillating bubble technique. It works in the frequency range from 1 Hz to 500 Hz, where surfactant exchange dynamics governs the relaxation process. The originality of instrument design is the consistent combination of modern measurement technologies with advanced imaging and signal processing algorithms. Key steps on the way to reliable and precise measurements are the excitation of harmonic oscillation of the bubble, phase sensitive evaluation of the pressure response, adjustment and maintenance of the bubble shape to half sphere geometry for compensation of thermal drifts, contour tracing of the bubbles video images, removal of noise and artefacts within the image for improving the reliability of the measurement, and, in particular, a complex trigger scheme for the measurement of the oscillation amplitude, which may vary with frequency as a result of resonances. The corresponding automation and programming tasks are described in detail. Various programming strategies, such as the use of MATLAB® software and native C++ code are discussed. An advance in the measurement technique is demonstrated by a fully automated measurement. The instrument has the potential to mature into a standard technique in the fields of colloid and interface chemistry and provides a significant extension of the frequency range to established competing techniques and state-of-the-art devices based on the same measurement principle. KW - automated measurements KW - DILATATIONAL PROPERTIES KW - dilational modulus KW - graphical user interfaces KW - image processing KW - MEDIUM FREQUENCY-RANGE KW - OSCILLATING BUBBLE TECHNIQUE KW - RHEOLOGY KW - signal processing KW - STABILITY KW - surface rheology KW - TENSIOMETRY Y1 - 2016 U6 - https://doi.org/10.1088/0957-0233/27/6/065301 VL - 27 IS - 6 PB - IOP Science ER - TY - JOUR A1 - Khaled, W. A1 - Bruhns, Otto T. A1 - Reichling, S. A1 - Böse, Holger A1 - Baumann, Michael A1 - Monkman, Gareth J. A1 - Egersdörfer, Stefan A1 - Meier, Alexander A1 - Klein, Dagmar A1 - Freimuth, Herbert A1 - Ermert, Helmut T1 - A haptic system for virtual reality applications based on ultrasound elastography and electrorheological fluids JF - Acoustical Imaging Y1 - 2004 U6 - https://doi.org/10.1007/978-1-4020-2402-3_85 IS - 27 SP - 667 EP - 675 PB - Kluver Academic CY - Dordrecht & New York ER - TY - CHAP A1 - Mayer, M. A1 - Monkman, Gareth J. T1 - Modern permanent magnetic materials: Advances and limits T2 - Inductica - Berlin Messe, 22-24 May 2007 Y1 - 2007 ER - TY - JOUR A1 - Petchartee, Somrak A1 - Monkman, Gareth J. T1 - Contact Recognition using Tactile Sensor JF - Annals Universitaria Craiova-Series: Automation, Computers, Electronics and Mechatronics N2 - The surface recognition algorithm that determines the types of contact surfacesby fusing information collected by the tactile sensor system is proposed. The tactilesystem will be determined from the shape of the object image which can then becharacterized using the mathematical properties of Quadric surface. This algorithm canrecognize 3-D objects using a 2-fingered robot gripper, on which tactile sensors aremounted. Experiments have demonstrated the reliability of the surface classificationmethod and the accuracy of transformations independent of an object’s shape, translationand rotation. Y1 - 2007 UR - https://www.academia.edu/1204885/CONTACT_RECOGNITION_USING_TACTILE_SENSOR VL - 4 (31) IS - 2 SP - 103 EP - 108 ER - TY - CHAP A1 - Petchartee, Somrak A1 - Monkman, Gareth J. T1 - Contact Recognition using Tactile Sensor T2 - Proc. International Symposium on System Theory, Automation, Robotics, Computers, Informatics, Electronics and Instrumentation (SINTES13), Romania Y1 - 2007 SP - 285 EP - 290 ER - TY - JOUR A1 - Petchartee, Somrak A1 - Monkman, Gareth J. T1 - Pre-slip Sensing through Tactile Sensing JF - Sensors & Transducers Y1 - 2008 UR - https://www.sensorsportal.com/HTML/DIGEST/P_SI_48.htm SN - 1726-5479 VL - 90 IS - 4, Special Issue SP - 310 EP - 324 PB - International Frequency Sensor Association (IFSA) ER - TY - CHAP A1 - Petchartee, Somrak A1 - Monkman, Gareth J. T1 - Pre-slip detection based Tactile Sensing T2 - Proc. 3rd International Conference on Intelligent Sensors, Sensor Networks and Information Processing (ISSNIP 2007), Melbourne Y1 - 2007 SP - 233 EP - 238 ER - TY - CHAP A1 - Petchartee, Somrak A1 - Monkman, Gareth J. T1 - Pre-slip Sensing through Tactile Sensing T2 - Proc. 2nd International Conference on Sensing Technology (ICST 2007), New Zealand Y1 - 2007 SP - 62 EP - 67 ER - TY - JOUR A1 - Trost, Tobias A1 - Sterner, Michael A1 - Bruckner, Thomas T1 - Impact of electric vehicles and synthetic gaseous fuels on final energy consumption and carbon dioxide emissions in Germany based on long-term vehicle fleet modelling JF - Energy N2 - Based on a prospective scenario analysis, possible vehicle fleet developments for the individual motor car traffic (vehicle categories N1 and M1) are investigated for Germany in order to determine the long-term vehicle fleet structure, final energy demand, and related carbon dioxide emissions until the year 2050. In this framework, a vehicle fleet model was developed which combines a bottom-up consumer demand model with a dynamic stock-flow approach. Special emphasis is thereby given to different electric power-trains and synthetic gaseous fuels based on the power-to-gas technology. In detail, two different main scenarios are developed and, in addition, the impact of different carbon dioxide taxation levels of fossil fuels on the vehicle fleet structure are analysed. The scenario results reveal a broad range of possible future vehicle fleet structures. In the short to medium timeframe, the internal combustion engine dominates the fleet as a result of efficiency improvements and an increased use of natural gas as automotive fuel. The development of electric power-trains is initially marked by hybrid vehicles, whereas battery electric vehicles dominate the fleet structure in the long-term. Under favourable conditions, also synthetic gaseous fuels are competitive which can reduce carbon dioxide emissions even further. KW - Carbon dioxide emissions KW - Electric vehicles KW - Final energy consumption KW - Power-to-gas KW - Total cost of ownership KW - Vehicle fleet modelling Y1 - 2017 U6 - https://doi.org/10.1016/j.energy.2017.10.006 SN - 0360-5442 VL - 141 SP - 1215 EP - 1225 PB - Elsevier ER - TY - CHAP A1 - Sterner, Michael A1 - Thema, Martin ED - Sterner, Michael ED - Stadler, Ingo T1 - Comparison of Storage Systems T2 - Handbook of Energy Storage N2 - There are several approaches to classifying energy storage systems (see Chaps. 1 and 2). Storage systems are used in a large number of different technologies at various stages of development, and in a wide range of application areas (see Chaps. 3 to 5). This chapter compares the capabilities of the different storage systems using the following criteria:This comparison of storage systems also provides a convenient overview of the various storage systems and their capabilities. Y1 - 2019 SN - 978-3-662-55503-3 U6 - https://doi.org/10.1007/978-3-662-55504-0_12 VL - 6 SP - 637 EP - 672 PB - Springer CY - Berlin, Heidelberg ER - TY - JOUR A1 - Sterner, Michael A1 - Specht, Michael T1 - Power-to-Gas and Power-to-X-The History and Results of Developing a New Storage Concept JF - Energies N2 - Germany's energy transition, known as 'Energiewende', was always very progressive. However, it came technically to a halt at the question of large-scale, seasonal energy storage for wind and solar, which was not available. At the end of the 2000s, we combined our knowledge of both electrical and process engineering, imitated nature by copying photosynthesis and developed Power-to-Gas by combining water electrolysis with CO2-methanation to convert water and CO2 together with wind and solar power to synthetic natural gas. Storing green energy by coupling the electricity with the gas sector using its vast TWh-scale storage facility was the solution for the biggest energy problem of our time. This was the first concept that created the term 'sector coupling' or 'sectoral integration'. We first implemented demo sites, presented our work in research, industry and ministries, and applied it in many macroeconomic studies. It was an initial idea that inspired others to rethink electricity as well as eFuels as an energy source and energy carrier. We developed the concept further to include Power-to-Liquid, Power-to-Chemicals and other ways to 'convert' electricity into molecules and climate-neutral feedstocks, and named it 'Power-to-X'at the beginning of the 2010s. KW - 100% renewable energy scenarios KW - CARBON RECYCLING SYSTEM KW - CO2 KW - eFuels KW - electric fuels KW - energy transition KW - hydrogen KW - methanation KW - METHANOL KW - Power-to-Gas KW - Power-to-Hydrogen KW - Power-to-Methane KW - Power-to-X KW - sector coupling KW - sectoral integration KW - TRANSPORTATION Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-26202 N1 - Corresponding author: Michael Sterner VL - 14 IS - 20 PB - MDPI ER - TY - GEN A1 - Sterner, Michael T1 - Gas aus einer Gesamtenergieversorgungsperspektive - Warum wir Power-to-X für die Klimaneutralität brauchen T2 - Kopernikus-Konferenz Projekt "Ensure" (Deutsche Umwelthilfe), 15. April 2021 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Sektorenkopplung KW - Power-to-Gas Y1 - 2021 ER - TY - JOUR A1 - Keiner, Dominik A1 - Breyer, Christian A1 - Sterner, Michael T1 - Coupling heat and electricity storage technologies for cost and self-consumption optimised residential PV prosumer systems in Germany JF - International Journal of Sustainable Energy Planning and Management N2 - Coupling energy sectors within the emerging residential PV prosumer systems is necessary for an optimised use of the houseowners’ own produced electricity. But the pure availability of different energy technologies in the system is not enough. By optimising the electricity usage as well as the capacities of PV generators, storage technologies, heat pumps and battery electric vehicles, not only the best solution in a technical point of view can be achieved, the need of finding the most financially beneficial system composition for single-family houses and tenements is possible. The study provides a detailed model for average German single-family houses and tenements and results for the energy transition period until 2050 for the optimised energy systems regarding optimised PV and stationary battery capacities and different heat storage capacities. Most noticeable outcomes can be observed by using a vehicle-to-home car, where a car can mostly take over the tasks of a stationary battery and by introducing a solidarity model using this type of car in tenement systems. Y1 - 2019 U6 - https://doi.org/10.5278/ijsepm.2019.21.4 VL - 21 PB - OJS/PKP ER - TY - INPR A1 - Gärtner, Sebastian A1 - Marx-Schubach, Thomas A1 - Gaderer, Matthias A1 - Schmitz, Gerhard A1 - Sterner, Michael T1 - Introduction of an Innovative Energy Concept for low Emission Glass Melting based on Carbon Capture and Usage N2 - Due to the very high fossil energy demand, the glass industry is looking for innovative approaches for the reduction of CO2 emissions and the integration of renewable energy sources. In this paper, we present a novel power-to-gas concept, which has no impact on established melting processes and discuss it for this purpose. A special focus is set on the required CO2 capture from typical flue gases in the glass industry, as this process has not been investigated in detail yet. We used a process simulation approach to investigate post-combustion CO2 capture by absorption processes, followed by a techno-economic evaluation. Our investigations found the designed CO2 capture plant to be approx. 400 times smaller than absorption based CO2 separation processes for conventional power plants. Due to the many options for waste heat utilization, the waste heat required for CO2 desorption can be generated in a particularly efficient and cost-effective way. The resulting CO2 avoidance costs range between 41-42 €/t CO2, depending on waste heat utilization for desorption, and thus offer a cost effective way of CO2 removal from glass industry melting processes. These costs are well below the values of 50-65 €/t CO2 described so far for comparable industrial applications. In addition, we describe optimization options, like solvent and process improvements, to enable further cost reductions. These results motivate further research and development on the overall process presented in this work. KW - glass KW - Oxyfuel KW - Methanation KW - Power-to-Gas KW - CO2 capture KW - Economic Analysis Y1 - 2022 U6 - https://doi.org/10.31224/2642 ER - TY - JOUR A1 - Kaul, Anja A1 - Boellmann, Andrea A1 - Thema, Martin A1 - Kalb, Larissa A1 - Stoeckl, Richard A1 - Huber, Harald A1 - Sterner, Michael A1 - Bellack, Annett T1 - Combining a robust thermophilic methanogen and packing material with high liquid hold-up to optimize biological methanation in trickle-bed reactors JF - Bioresource technology N2 - The hydrogen gas-to-liquid mass transfer is the limiting factor in biological methanation. In trickle-bed reactors, mass transfer can be increased by high flow velocities in the liquid phase, by adding a packing material with high liquid hold-up or by using methanogenic archaea with a high methane productivity. This study developed a polyphasic approach to address all methods at once. Various methanogenic strains and packings were investigated from a microbial and hydrodynamic perspective. Analyzing the ability to produce high-quality methane and to form biofilms, pure cultures of Methanothermobacter performed better than those of the genus Methanothermococcus. Liquid and static hold-up of a packing material and its capability to facilitate attachment was not attributable to a single property. Consequently, it is recommended to carefully match organism and packing for optimized performance of trickle-bed reactors. The ideal combination for the ORBIT system was identified as Methanothermobacter thermoautotrophicus IM5 and DuraTop (R). KW - BIOCATALYTIC METHANATION KW - CARBON-DIOXIDE KW - hydrogen KW - Liquid hold-up maximization KW - MASS-TRANSFER KW - Methane production KW - Methanothermobacter KW - Methanothermococcus KW - Optimized packing-organism combination KW - THERMOAUTOTROPHICUS Y1 - 2022 U6 - https://doi.org/10.1016/j.biortech.2021.126524 VL - 345 PB - Elsevier ER - TY - CHAP A1 - Kreuzer, Reinhard A1 - Haslbeck, Matthias A1 - Brückl, Oliver T1 - Modellierung von Mittelspannungsnetzen zur verbesserten Nachbildung von Wirk- und Blindleistungsflüssen T2 - Tagungsband der Fachtagung "Zukünftige Stromnetze für erneuerbare Energien" am 30./31. Januar 2018 in Berlin N2 - Das vom BMWi geförderte Forschungsprojekt SyNErgie (03/2015 bis 05/2018) beschäftigt sich mit der Weiterentwicklung von Netzplanungsprozessen [1]. Im Fokus steht dabei die Modellierung von Blindleistungsflüssen und die dezentrale Nutzung von Blindleistungsquellen (z. B. Wechselrichter, Ladedrosseln, Kondensatoren) in Mittelspannungsnetzen, über welche der Blindleistungshaushalt letztendlich beeinflusst werden soll. Im Rahmen dieses Beitrags wird anhand eines realen Mittelspannungsnetzes (MS-Netz) gezeigt, welche Modellierungsschritte zur Erstellung eines möglichst realitätsnahen Simulationsabbilds nötig sind. Dies ist notwendig, um der Verteilnetzplanung eine robuste Planungsgrundlage für die Ableitung von Entscheidungen im Rahmen eines Blindleistungsmanagements zur Verfügung zu stellen. Y1 - 2018 UR - https://www.fenes.net/wp-content/uploads/2019/03/SyNErgie_Paper_2018_Kreuzer_Modellierung_MSNetze.pdf ER - TY - CHAP A1 - Rauch, Johannes A1 - Brückl, Oliver T1 - Entwicklung eines Regelverfahrens für einen optimierten und zentralen Blindleistungsabruf zur Beeinflussung des Blindleistungshaushaltes von Mittelspannungsverteilungsnetzen unter Einhaltung von Netzrestriktionen T2 - Zukünftige Stromnetze, 30.-31.Jan.2019, Berlin Y1 - 2019 SP - 421 EP - 437 PB - Conexio CY - Pforzheim ER - TY - JOUR A1 - Brückl, Oliver T1 - Plädoyer für die wettbewerbliche Bereitstellung von Blindleistung JF - ew - Magazin für die Energiewirtschaft - Spezial: Digitalisierung Y1 - 2018 UR - https://emagazin.ew-magazin.de/de/profiles/a21024e15cd4/editions/dd6db0d02570767aa71f VL - 117 IS - 1 SP - 46 EP - 48 PB - VDE Verlag ER - TY - CHAP A1 - Haslbeck, Matthias T1 - Innovative Aspekte der Netzplanung im Verteilungsnetz T2 - 2. OTTI-Konferenz Zukünftige Stromnetze für Erneuerbare Energien, Hilton-Hotel Berlin, 27./28. Januar 2015 N2 - In den Verteilungsnetzen (VN) besteht erheblicher Optimierungsbedarf, um die geplanten Leistungen an dezentralen Erzeugungsanlagen (EZA) aufnehmen und um die erzeugte Energie an das Übertragungsnetz abgeben zu können. Bislang konnte der Aufwand für die Netzplanung im VN mittels standardisierter Abläufe und großzügigen Reserven im Spannungsband und der Stromtragfähigkeit begrenzt werden. Im Zuge des Zubaus an EZA schwinden diese Reserven und Netzplanungsaufgaben müssen individueller für einzelne Netzabschnitte gelöst werden. Die Forschungsstelle für Energienetze und Energiespeicher (FENES) der OTH Regensburg beschäftigt sich u. a. mit der Fragestellung wie die Netzplanung im Verteilungsnetz hinsichtlich der neu entstandenen Herausforderungen optimiert werden kann und gleichzeitig praktikabel bleibt. Kernthemen sind dabei das Spannungs- und das Blindleistungsmanagement im Verteilungsnetz. Im Zuge der Energiewende gilt es die vorhandene Netzinfrastruktur noch effizienter auszunutzen und den Ausbau noch stärker bedarfsorientiert zu gestalten. Infolgedessen bewegt sich der Netzbetrieb näher an den Grenzen der Netzparameter (z. B. Spannungshaltung und Auslastung). Von daher müssen bislang praktizierte Verfahren weiter entwickelt werden, , um weiterhin einen sicheren und stabilen Netzbetrieb zu gewährleisten. KW - Energienetz KW - Energiespeicher KW - Energiewende KW - Leistungsmanagement KW - Netzbetrieb KW - Netzplanung KW - Spannband KW - Stromtragfähigkeit Y1 - 2015 SN - 978-3-943891-46-1 SP - 110 EP - 115 CY - Regensburg ER - TY - GEN A1 - Sterner, Michael T1 - Insight into Power-to-Gas/Liquids: a solution for sustainable transport besides e-mobility T2 - Conference Low Carbon Transport - Engineering the Fuels of the Future (Institution of Mechanical Engineers), London 09.07.2019 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Sektorenkopplung KW - Power-to-Gas Y1 - 2019 PB - Institution of Mechanical Engineers CY - London ER - TY - CHAP A1 - Kraus, Hermann A1 - Gschoßmann, David A1 - Brückl, Oliver T1 - Automatisierung von Netzplanungsprozessen in der Verteilnetzebene – Q(U)- und cosj(P)-Blindleistungsregelung dezentraler Anlagen als spannungshaltende Netzausbaumaßnahmen T2 - Tagungsband Zukünftige Stromnetze 2019, 30.-31.Jan.2019, Berlin N2 - Diese Arbeit befasst sich mit automatisierten Netzplanungsprozessen und gibt einen kurzen Einblick in das Entscheidungsunterstützungssystem, welches im EU-Projekt CrossEnergy entwickelt wird. Detaillierter wird aber auf die Konzipierung und Umsetzung eines automatisierten Einsatzes der Blindleistungsregelung von dezentralen Erzeugungs­ analgen eingegangen, die als spannungshaltende Netzausbaumaßnahme zur Verfügung stehen. Die vorgestellten Methoden und Algorithmen fokussieren sich auf die Q(U)- und coscp(P)-Regelungsarten. Y1 - 2019 SP - 407 EP - 420 PB - Connexio CY - Pforzheim ER - TY - RPRT A1 - Sterner, Michael A1 - Thema, Martin A1 - Eckert, Fabian A1 - Moser, Albert A1 - Schäfer, Andreas A1 - Drees, Tim A1 - Christian Rehtanz, A1 - Ulf Häger, A1 - Kays, Jan A1 - Seack, André A1 - Dirk Uwe Sauer, A1 - Matthias Leuthold, A1 - Philipp Stöcker, T1 - Stromspeicher in der Energiewende - Untersuchung zum Bedarf an neuen Stromspeichern in Deutschland für den Erzeugungsausgleich, Systemdienstleistungen und im Verteilnetz BT - Studie N2 - Wie groß ist der Speicherbedarf in Deutschland in der weiteren Umsetzung der Energiewende? Welche Rolle spielen Batteriespeicher, Pumpspeicher, Power-to-Gas etc. im Kontext anderer Flexibilitätsoptionen auf den verschiedenen Netzebenen? Wie entwickelt sich der Markt für Batterien und Wasserstoff? In unserer Agora-Speicherstudie haben wir auch erstmalig den Begriff Power-to-X definiert und damit die bis dato entstandenen Begriffe Power-to-Gas, Power-to-Liquids, Power-to-Products, Power-to-Chemicals etc. zusammengefasst. Y1 - 2014 U6 - https://doi.org/10.13140/RG.2.2.31804.56964 PB - Agora Energiewende CY - Berlin ER - TY - CHAP A1 - Stadler, Ingo A1 - Eckert, Fabian ED - Sterner, Michael ED - Stadler, Ingo T1 - Lastmanagement als Energiespeicher T2 - Energiespeicher - Bedarf, Technologien, Integration KW - Lastverteilung KW - Energiespeicher Y1 - 2017 SN - 978-3-662-48893-5 SN - 978-3-662-48892-8 U6 - https://doi.org/10.1007/978-3-662-48893-5_11 SP - 619 EP - 644 PB - Springer Vieweg CY - Berlin ; Heidelberg ET - 2. Auflage ER - TY - CHAP A1 - Sterner, Michael A1 - Eckert, Fabian A1 - Henning, Hans-Martin A1 - Trost, Tobias ED - Sterner, Michael ED - Stadler, Ingo T1 - Storage Demand in the Transport and Chemical Sector T2 - Handbook of Energy Storage N2 - In the transport sector, energy transition is still in its beginnings: shares of renewable fuels are at 5% and are, with the exception of a small percentage in electrical rail transport, almost entirely restricted to biofuel. The transport sector, i.e., road, air, shipping, and rail traffic, consumes around 30% of all final energy in Germany and its dependency of over 90% on petroleum is still very high. As a result, its shares in greenhouse gas emissions are at 20%. The necessary structural change in mobility, based on energy transition, is closely linked to the question of operating energy and of energy storage also. Aside from vehicles directly powered by wind or solar energy, mobility without storage is not possible: fuel tanks in cars, gas stations, and airplanes are omnipresent. The focus of the considerations on storage demand in the transport sector is on the question of how these storages can be used with renewable energies via bio and synthetic fuels, and on the question of how much storage is necessary for these new drive technologies, such as e-mobility. Before this, mobility needs today and in future need to be examined. In the chemical sector, the situation is very much alike: there is a great dependency on fossil resources, and decarbonization is inevitable to achieve ambitious climate goals. The structural change to convert and store renewable electricity as primary energy via power-to-X (PtX) represents a storage demand. First estimates will conclude this chapter. Y1 - 2019 SN - 978-3-662-55503-3 U6 - https://doi.org/10.1007/978-3-662-55504-0_5 SP - 165 EP - 188 PB - Springer CY - Berlin, Heidelberg ER - TY - CHAP A1 - Sterner, Michael A1 - Breuer, Christopher A1 - Drees, Tim A1 - Eckert, Fabian A1 - Maaz, Andreas A1 - Pape, Carsten A1 - Rotering, Niklas A1 - Thema, Martin ED - Sterner, Michael ED - Stadler, Ingo T1 - Storage Demand in Power Supply T2 - Handbook of Energy Storage N2 - Energy storage systems (in the past as well as today) are one significant part in the energy supply. The following three chapters describe how storage demand will develop in the future for the electricity, heat, and traffic sectors, as well as for non-energetic consumption of fossil resources (the chemical industry). Chapter 3, the core of this section on storage demand, makes clear how and why the electricity sector is the nucleus of the energy supply of all sectors and why it creates essential bridges between electricity, heat, and transport sectors, as well as with the chemical industry. If planned electricity network expansion takes place and flexibilities in generation and consumption are fully exploited, the demand for electricity storage, according to present estimates, will only reach a significant scale at 60–80% shares of renewable energy in the power supply. Network expansion has a great impact on the storage demand, as well as flexible power generation in power plants, combined heat and power (CHP), and flexible consumption via demand-side management (DSM). Four studies in the context of storage demand and the role of energy storage systems for flexibility are comprehensively addressed. The authors and the co-authors were themselves participants in these studies, which will be complemented by ongoing research. A meta-study summary of the main results is shown in Abschn. 3.7, and these results are compared with seven further studies. Y1 - 2019 SN - 978-3-662-55503-3 U6 - https://doi.org/10.1007/978-3-662-55504-0_3 SP - 51 EP - 136 PB - Springer CY - Berlin, Heidelberg ER - TY - CHAP A1 - Sterner, Michael ED - Sterner, Michael ED - Stadler, Ingo T1 - Energy Storage Through the Ages T2 - Handbook of Energy Storage N2 - Human beings have relied on stored energy since time immemorial. The planet’s first mechanism for storing energy arose two billion years ago. Photosynthesis captures solar energy in chemical bonds; it is a process on which all life depends. With the discovery of fire around one-and-a-half million years ago, early man learned to access this stored energy by burning wood. Only since the Industrial Revolution have humans used fossil fuels, which are the results of biomass produced millions of years ago, then subjected to geological processes. Today, the long-term objective is to utilize sustainable biomass storage, replicate it by technical means, and to develop new storage technologies. This chapter is about the history of energy storage as it pertains to the carbon cycle. It begins with a natural energy storage system—photosynthesis—and examines its products biomass, peat, and fossil fuels before turning to storage technology in the era of renewable energies. It will also discuss how stored energy is used. This chapter focuses on natural biogenic and fossil energy storage. Other chapters are devoted to artificial storage technologies, including batteries, pumped-storage, and power-to-gas (PtG). Each begins with a short history of its respective technology. Y1 - 2019 SN - 978-3-662-55503-3 U6 - https://doi.org/10.1007/978-3-662-55504-0_1 SP - 3 EP - 22 PB - Springer CY - Berlin, Heidelberg ER - TY - CHAP A1 - Sterner, Michael A1 - Stadler, Ingo A1 - Eckert, Fabian A1 - Gerhardt, Norman A1 - von Olshausen, Christian A1 - Thema, Martin A1 - Trost, Tobias ED - Sterner, Michael ED - Stadler, Ingo T1 - Storage Integration for Coupling Different Energy Sectors T2 - Handbook of Energy Storage N2 - Electricity is becoming the primary source of energy, a trend that is particularly apparent through the coupling of the electricity sector with other energy sectors. In addition to the established links between the electricity and heating sectors using combined heat and power (CHP), which is supplemented by electric heat-pumps and power-to-heat (PtH), other new links are also emerging. These links are manifesting in the form of electro-mobility and electric fuels in the electricity and transport sectors; and in the electricity and gas sector they are appearing in the form of power-to-gas (PtG). The production of basic chemical materials such as methanol or polymers using electrical energy, water, and CO2 will also play a role in the future. However, the latter will not be dealt with explicitly here. Instead we will consider in detail other aspects of electricity as a primary energy source and its integration and application for energy storage. Y1 - 2019 SN - 978-3-662-55503-3 U6 - https://doi.org/10.1007/978-3-662-55504-0_14 SP - 757 EP - 803 PB - Springer CY - Berlin, Heidelberg ER - TY - CHAP A1 - Sterner, Michael A1 - Stadler, Ingo A1 - Eckert, Fabian A1 - Thema, Martin ED - Sterner, Michael ED - Stadler, Ingo T1 - Storage Integration in Individual Energy Sectors T2 - Handbook of Energy Storage N2 - How is energy storage integrated and currently implemented in the electricity supply, heating supply, and mobility sectors? This chapter provides both theoretical and practical answers to that question. The chapter focuses on the integration of renewable energy. Cross-sectoral energy storage systems that link the electricity, heating, and mobility sectors are discussed in Kap. 14. This chapter focuses on storage integration in the electricity sector. After considering stand-alone networks, the chapter uses practical examples to analyze the various storage applications in the European network. The chapter concludes with a discussion of storage integration in the heating and transportation sectors. Y1 - 2019 SN - 978-3-662-55503-3 U6 - https://doi.org/10.1007/978-3-662-55504-0_13 SP - 675 EP - 755 PB - Springer CY - Berlin, Heidelberg ER - TY - CHAP A1 - Sörgel, Matthias A1 - Riederer, Michael A1 - Held, Andreas A1 - Plake, Daniel A1 - Zhu, Zhilin A1 - Foken, Thomas A1 - Meixner, Franz X. ED - Foken, Thomas T1 - Trace Gas Exchange at the Forest Floor T2 - Energy and Matter Fluxes of a Spruce Forest Ecosystem N2 - Exchange conditions at the forest floor are complex due to the heterogeneity of sources and sinks and the inhomogeneous radiation but are important for linking soil respiration to measurements in the trunk space or above canopy. Far more attention has therefore been paid to above and within canopy flows, but even studies that addressed forest floor exchange do not present measurements below 1 m or 2 m. We used a multilayer model that explicitly resolves the laminar layer, the buffer layer, and the turbulent layer to calculate fluxes from the measured profiles in the lowest meter above ground and to calculate effective surface concentrations from given fluxes. The calculated fluxes were compared to measured eddy covariance fluxes of sensible heat and O3 and to chamber derived soil fluxes of CO2 and 222Rn. Sensible heat fluxes agreed surprisingly well given the heterogeneity of radiative heating and the generally low fluxes (max. 25 W m−2). The chamber fluxes turned out to be not comparable as the chamber fluxes were too low, probably due to one of the well-known problems of enclosures such as pressure differences, disturbed gradients and exclusion of naturally occurring turbulence events and surface cooling. The O3 fluxes agreed well for high O3 values reaching down to the forest floor during full coupling of the canopy by coherent structures. During most of the time, the model overestimated the fluxes as chemical reactions were dominating within the profile. One new approach was to calculate the effective surface concentration from a given flux and compare this to measured surface concentrations. This allowed the identification of situations with a coupled and decoupled forest floor layer, which has important consequences for respiration measurements in the trunk space or above canopy and should be considered in upcoming studies. KW - Chamber Flux KW - Eddy Covariance KW - Forest Floor KW - Multilayer Model KW - Nitrogen Oxide Y1 - 2017 SN - 978-3-319-49387-9 U6 - https://doi.org/10.1007/978-3-319-49389-3_8 VL - 229 SP - 157 EP - 179 PB - Springer CY - Cham ER - TY - CHAP A1 - Sterner, Michael A1 - Bauer, Franz ED - Sterner, Michael ED - Stadler, Ingo T1 - Definition and Classification of Energy Storage Systems T2 - Handbook of Energy Storage N2 - Energy supply always requires energy storage—either as an intrinsic property or as additional system. It is an intrinsic property of solid, liquid, and gaseous fuels, although less so of water-borne heat, but not of electricity. So to meet variable demands and supplies, heat and electricity networks usually require additional storage systems. When they are added to an energy network, should they be viewed as ‘suppliers’ or as ‘consumers’? Who is responsible for covering the costs of storage systems? To categorize storage systems in the energy sector, they first need to be carefully defined. This chapter defines storage as well as storage systems, describes their use, and then classifies storage systems according to temporal, spatial, physical, energy-related, and economic criteria. Y1 - 2019 SN - 978-3-662-55503-3 U6 - https://doi.org/10.1007/978-3-662-55504-0_2 SP - 23 EP - 47 PB - Springer CY - Berlin, Heidelberg ER - TY - CHAP A1 - Stadler, Ingo A1 - Sterner, Michael ED - Droege, Peter T1 - Urban Energy Storage and Sector Coupling T2 - Urban Energy Transition N2 - Global warming, greenhouse gas emissions, and the general transition toward renewable energy resources are mentioned many times within this book, and will not be repeated again here. Countries that are transitioning to use of more renewable energy sources are mainly using wind and solar power—except for a few countries that, due to their prerequisites, will mainly use hydro power and/or bioenergy. The transmission process in terms of energy generation so far is mainly happening in rural areas—not in urban centers. Most technologies do not really play an important role in urban areas, and are mainly focused on the application of solar energy. Solar energy is widely applied more in rural areas, although investigations show that its application in urban areas already fits well into the existing grid infrastructure. Whereas rural areas are more prone to grid integration problems, the energy infrastructure in urban centers is already well prepared for renewables integration. In fostering tight bundles of potentially linked energy generation, distribution, networking, and use across power and thermal systems in stationary and mobile modes, urban centers become particularly critical in the energy transition processes as energy systems are becoming completely based on renewable sources without a nuclear or fossil-based backbone. This chapter discusses the almost unlimited energy storage possibilities. It will show their enormous capabilities, but also their significant differences in many physical and economical parameters. Next, the authors discuss the necessity of combining and coupling the different energy sectors for electricity, heat, cold, gas, and transport. Finally, the authors present the conclusion that only when coupling the energy sectors and using cheap and efficient energy storage options from one energy sector to solve challenges within another energy sector will the energy transition process be managed in an efficient way. KW - Energy storage KW - energy transition KW - Greenhouse gas emissions KW - RENEWABLE ENERGY KW - Renewable sources KW - sector coupling Y1 - 2018 SN - 978-0-08-102074-6 U6 - https://doi.org/10.1016/B978-0-08-102074-6.00026-7 SP - 225 EP - 244 PB - Elsevier ET - 2. ed. ER - TY - JOUR A1 - Thema, Johannes A1 - Thema, Martin T1 - Nachnutzungskonzept: Braunkohle-Tagebaue als Pumpspeicherkraftwerk? JF - Energiewirtschaftliche Tagesfragen - et : Zeitschrift für Energiewirtschaft, Recht, Technik und Umwelt N2 - Der Anteil fluktuierender erneuerbarer Energien im deutschen Strommix steigt. Um die Netzstabilität zu erhalten, Fluktuationen im Dargebot nach Wetterlage und saisonal auszugleichen sind absehbar ab ca. 2030 große Stromspeicherkapazitäten erforderlich. Wasser-Pumpspeicherwerke sind derzeit die einzige langjährig erprobte Technologie, die künftig in Braunkohletagebauen, welche im Zuge der Energiewende aufgegeben werden, errichtet werden könnten. Eine Überschlagsrechnung am Beispiel eines Pumpspeicherwerks in verschiedenen Tagebauen zeigt, dass diese mit bis zu 400 GWh ein signifikantes technisches Speicherpotenzial haben. KW - Braunkohle KW - Energiewende KW - erneuerbare Energie KW - Pumpspeicherwerk KW - Speicherkapazität KW - Tagebau Y1 - 2019 VL - 69 IS - 4 SP - 38 EP - 39 PB - ETV Energieverl. CY - Essen ER - TY - INPR A1 - Kaul, Anja A1 - Böllmann, Andrea A1 - Thema, Martin A1 - Kalb, Larissa A1 - Stöckl, Richard A1 - Huber, Harald A1 - Sterner, Michael A1 - Bellack, Annett T1 - Identification of Robust Thermophilic Methanogenic Archaea and Packing Material for High Liquid Hold-Up at Low Volumetric Gas Flow Rates for Use in Trickle-Bed Reactors for Biological Methanation T2 - SSRN Electronic Journal N2 - he hydrogen gas-to-liquid mass transfer is the limiting factor in biological methanation. In a trickle-bed reactor, mass transfer can be increased by high flow velocities in the liquid phase, by adding a packing material with high liquid hold-up, or by choosing methanogenic archaea with a high methane productivity. This study analyzed various packings and methanogenic strains from a hydrodynamic and microbial perspective. By analyzing twelve pure cultures of thermophilic methanogens for their ability to produce high quality methane and to form biofilms on different packings, strains of Methanothermobacter were found to perform better than thus of the genus Methanothermococcus. Best methane production and adherence was observed on DuraTop®, Bioflow 9, and filter foam. DuraTop® and Bioflow 9 had also a high dynamic liquid hold-up, but the maximum hold-up was determined for expanded clay. The ideal combination for use in the ORBIT-trickle-bed reactor was identified as Methanothermobacter thermoautotrophicus IM5 and DuraTop®. KW - Liquid hold-up maximization KW - Methane production KW - Methanothermobacter KW - Methanothermococcus KW - Optimized packing-organism combination Y1 - 2021 U6 - https://doi.org/10.2139/ssrn.3940878 N1 - final peer reviewed article published under: https://doi.org/10.1016/j.biortech.2021.126524 ER - TY - CHAP A1 - Sterner, Michael A1 - Bauer, Franz A1 - Hofrichter, Andreas ED - Ausfelder, Florian ED - Dura, Hanna Ewy T1 - Systemanalyse von Power-to-X-Pfaden - Ergebnisse des Satellitenprojektes "SPIKE" T2 - Optionen für ein nachhaltiges Energiesystem mit Power-to-X Technologien : Nachhaltigkeitseffekte - Potenziale Entwicklungsmöglichkeiten; 2. Roadmap des Kopernikus-Projektes "Power-to-X": Flexible Nutzung erneuerbarer Ressourcen (P2X) Y1 - 2019 UR - https://edocs.tib.eu/files/e01fn21/1770760199.pdf SN - 978-3-89746-218-2 SP - 145 EP - 153 PB - DECHEMA Gesellschaft für Chemische Technik und Biotechnologie e.V CY - Frankfurt am Main ER - TY - JOUR A1 - Haslbeck, Matthias A1 - Brückl, Oliver T1 - Netzplanung Mittelspannungsnetze: Abbildung eines innovativen Blindleistungsmanagements, Teil 1 und 2 JF - ew - Magazin für die Energiewirtschaft Y1 - 2020 IS - 7-8 und 9 SP - 36 EP - 39 ER - TY - CHAP A1 - Sterner, Michael A1 - Bauer, Franz A1 - Crotogino, Fritz A1 - Eckert, Fabian A1 - von Olshausen, Christian A1 - Teichmann, Daniel A1 - Thema, Martin ED - Sterner, Michael ED - Stadler, Ingo T1 - Chemical Energy Storage T2 - Handbook of Energy Storage N2 - Purely electrical energy storage technologies are very efficient, however they are also very expensive and have the smallest capacities. Electrochemical-energy storage reaches higher capacities at smaller costs, but at the expense of efficiency. This pattern continues in a similar way for chemical-energy storage. In terms of capacities, the limits of batteries (accumulators) are reached when low-loss long-term storage is of need. Chemical-energy storage and stocking fulfills these requirements completely. The storing itself may be subject to significant efficiency losses, but, from today’s point of view and in combination with the existing gas and fuel infrastructure, it is the only national option with regards to the long-term storage of renewable energies. Chemical-energy storage is the backbone of today’s conventional energy supply. Solid (wood and coal), liquid (mineral oil), and gaseous (natural gas) energy carriers are ‘energy storages’ themselves, and are stored using different technologies. In the course of energy transition, chemical-energy storage will be of significant importance, mainly as long-term storage for the power sector, but also in the form of combustibles and fuels for transport and heat. Not only are conventional storing technologies discussed within this chapter, but a detailed explanation is also given about the storage of renewable energies in the form of gaseous (power-to-gas, PtG) and liquid (power-to-liquid, PtL) energy carriers for electricity, heat, chemicals, and in the form of synthetic fuels. Y1 - 2019 SN - 978-3-662-55503-3 U6 - https://doi.org/10.1007/978-3-662-55504-0_8 SP - 325 EP - 482 PB - Springer CY - Berlin, Heidelberg ER - TY - CHAP A1 - Sterner, Michael A1 - Eckert, Fabian A1 - Gerhardt, Norman A1 - Henning, Hans-Martin A1 - Palzer, Andreas ED - Sterner, Michael ED - Stadler, Ingo T1 - Heating Supply Storage Requirements T2 - Handbook of Energy Storage N2 - Unlike the electricity sector, heating and cooling storage requirements have attracted little public attention. This is because these storage requirements have generally already been met, and will not change significantly in the future. In the electricity sector by contrast, there will be a significant shift from primary energy storage to electricity and final energy storage. Both sectors have remarkably high storage requirements. Almost all households have thermal buffers. The same is true of renewable energy heating systems such as pellet heating, geothermal, or solar-thermal systems. Some households with liquid gas or oil heating even have two storage units: a fuel tank and a thermal buffer. Exceptions include heating systems with upstream storage such as district heating or gas storage. In the future, integration of the electricity and heating sectors by combined heat and power (CHP) generation, heat pumps, power-to-heat (PtH), and power-to-gas (PtG) will facilitate the use of renewable energy, and lead to a paradigm shift. Relying on results from various studies, this chapter examines the development of heating supply in Germany and the resulting thermal storage requirements. The chapter’s later sections provide surplus and storage potential estimates. Cooling requirements are included as ‘process cooling’ under ‘process heat’, and as ‘air-conditioning’ over ‘room heating’. It is primarily integrated into electricity demand. Y1 - 2019 SN - 978-3-662-55503-3 U6 - https://doi.org/10.1007/978-3-662-55504-0_4 SP - 137 EP - 163 PB - Springer CY - Berlin, Heidelberg ER - TY - CHAP A1 - Stadler, Ingo A1 - Bauer, Franz A1 - Budt, Marcus A1 - Heindl, Eduard A1 - Wolf, Daniel ED - Sterner, Michael ED - Stadler, Ingo T1 - Mechanical Energy Storage T2 - Handbook of Energy Storage N2 - Chemical-energy storage systems use caverns, porous storage facilities, tanks, and storage rooms to store chemical energy sources. Caverns, caves, and reservoirs can also be used to store gaseous media such as air, liquid media such as water, and solid media such as rock. The principles of mechanical energy storage are based on classical Newtonian mechanics, or in other words on fundamental physics from the eighteenth and nineteenth centuries. As a result, these types of storage are typically divided into two categories; storage of kinetic and potential energy, or storage of ‘pressure energy’. In this chapter, storage media is categorized by its aggregate state, and described by its function and application: first compressed air energy storage and then conventional electricity storage—pumped-storage plants. The chapter continues with a discussion of innovative methods of storing potential energy using water as a medium. These include artificially constructed pumped storage, pumped storage in the open sea, dam storage on rivers, pumped storage on heaps in repurposed mining areas, underfloor or underground pumped storage, and surface mine storage. The chapter concludes with a description of classical and modern flywheel energy storage systems. This age-old technology is then compared with a new concept: mechanical stored energy exploiting both pumped storage and change in the potential energy of rocks or large boulders. Y1 - 2019 SN - 978-3-662-55503-3 U6 - https://doi.org/10.1007/978-3-662-55504-0_9 SP - 483 EP - 561 PB - Springer Berlin Heidelberg CY - Berlin, Heidelberg ER - TY - JOUR A1 - Estermann, Thomas A1 - Newborough, Marcus N. A1 - Sterner, Michael T1 - Power-to-gas systems for absorbing excess solar power in electricity distribution networks JF - International Journal of Hydrogen Energy N2 - The feasibility of implementing power-to-gas systems, to absorb surplus solar power from electricity distribution networks and carbon dioxide from biomass anaerobic digestion (AD) plant, in order to produce synthetic methane was investigated for a region of Southern Germany that has a high solar power penetration. The analysis was based on time series electricity data for 2012 from which future load profiles were computed in accordance with the expected installed capacities of solar power across the period 2015–2025. The electrolyser capacity required to absorb 20% of excess solar energy occurring within the region's low voltage network in 2025 was estimated to be 370 MWe. First order considerations of the region's gas grid, electricity network and existing AD sites suggest that such a deployment could be achieved by installing sub-MW (and some multi-MW) power-to-gas plant at several hundred AD sites. KW - Energy storage KW - Power-to-gas KW - Solar power KW - Synthetic methane Y1 - 2016 U6 - https://doi.org/10.1016/j.ijhydene.2016.05.278 VL - 41 IS - 32 SP - 13950 EP - 13959 PB - Elsevier ER - TY - CHAP A1 - Stadler, Ingo A1 - Eckert, Fabian ED - Sterner, Michael ED - Stadler, Ingo T1 - Load Management as an Energy Storage System T2 - Handbook of Energy Storage N2 - Chapters 6 to 9 focused on storage systems that store electric energy in a range of forms, and then release the energy again as electric energy. Chapter 10 discussed the use of thermal-energy storage (TES) systems for thermal management. This chapter examines management methods. These methods use processes that typically convert electric energy into another form of final energy that can also be stored. This form of energy is often thermal energy. But unlike with the systems discussed in previous chapters, here the energy stored is not converted back into electricity. Instead, the energy is used and stored in the same form. From the point of view of the energy supply system, these management methods perform exactly the same function as energy storage systems. This chapter discusses load-management in general, then potential uses of load-management, and finally, current trends. Y1 - 2019 SN - 978-3-662-55503-3 U6 - https://doi.org/10.1007/978-3-662-55504-0_11 SP - 611 EP - 636 PB - Springer CY - Berlin, Heidelberg ER - TY - JOUR A1 - Thema, Martin A1 - Sterner, Michael A1 - Lenck, Thorsten A1 - Götz, Philipp T1 - Necessity and Impact of Power-to-gas on Energy Transition in Germany JF - Energy Procedia N2 - The present paper gives an outlook on a bandwidth of required installed power-to-gas capacity in the German power sector fed by 100% renewable generation until 2050. Two scenarios were simulated to quantify cost effects of power-to-gas on the electricity system: once with, once without additional short-term flexibility options to a system using fossil natural gas as sole flexibility option instead. As a result, at latest in 2035, power-to-gas capacity expansion has to take place to reach required installed capacities of up to 89-134 GW in 2050. Application of power-to-gas as long-term flexibility leads to cost savings of up to 11,7-19 bn Euro enabling a fully renewable system in 2050. KW - decarbonization KW - energy storage KW - energy transition KW - Power-to-Gas KW - renewable energy KW - supply security KW - surplus energy KW - system costs Y1 - 2016 U6 - https://doi.org/10.1016/j.egypro.2016.10.129 VL - 99 SP - 392 EP - 400 PB - Elsevier ER - TY - GEN ED - Sterner, Michael ED - Stadler, Ingo T1 - Handbook of Energy Storage BT - Demand, Technologies, Integration N2 - There are several approaches to classifying energy storage systems (see Chaps. 1 and 2). Storage systems are used in a large number of different technologies at various stages of development, and in a wide range of application areas (see Chaps. 3 to 5). This chapter compares the capabilities of the different storage systems using the following criteria:This comparison of storage systems also provides a convenient overview of the various storage systems and their capabilities. KW - Erneuerbare Energien KW - Power-to-Gas KW - Energiespeicher Y1 - 2019 SN - 978-3-662-55503-3 U6 - https://doi.org/10.1007/978-3-662-55504-0 PB - Springer-Nature CY - Heidelberg, Berlin, New York ET - Translation of 2nd German edition Sterner, „Stadler Energiespeicher – Bedarf, Technologien, Integration“ ER - TY - GEN A1 - Thema, Martin A1 - Bellack, Annett A1 - Weidlich, Tobias A1 - Huber, Harald A1 - Karl, Jürgen A1 - Sterner, Michael T1 - Optimierung biologischer CO2-Methanisierung im Rieselbett-Reaktor BT - das ORBIT-Projekt T2 - 4. Regensburger Energiekongress, Regensburg 26.-27.02.2019 KW - biologische Methanisierung KW - Archaeen KW - Power-to-Gas KW - Erneuerbare Energien KW - Rieselbett-Bioreaktor Y1 - 2019 ER - TY - GEN A1 - Thema, Martin A1 - Bauer, Franz A1 - Sterner, Michael T1 - Power-to-Gas world status report T2 - International Renewable Energy Storage Conference, Düsseldorf 14.-16.03.2019 KW - Erneuerbare Energien, Klimaneutralität, Energiewende, Sektorenkopplung, Power-to-Gas KW - Power-to-Gas KW - Sektorenkopplung KW - Energiewende KW - Klimaneutralität Y1 - 2019 ER - TY - GEN A1 - Sterner, Michael T1 - Sektorenkopplung mit Solarstrom: Theorie und Praxis T2 - 17. Nationale Photovoltaik-Tagung, Kursaal Bern, Schweiz 26.03.2019 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Sektorenkopplung KW - Solarstrom KW - Photovoltaik Y1 - 2019 ER - TY - GEN A1 - Sterner, Michael T1 - Ohne Speicher, Wasserstoff und Power-to-X keine Dekarbonisierung von Verkehr und Industrie – Möglichkeiten und Notwendigkeit der integrierten Sektorenkopplung T2 - CIGRE/CIRED Informationsveranstaltung 2020, Leipzig, 13.10.2020 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Sektorenkopplung KW - Klimaschutz KW - Energiespeicher KW - Power-to-X Y1 - 2020 ER - TY - GEN A1 - Sterner, Michael T1 - Power-to-Gas technologies in the energy sector and their role in the fight against climate change T2 - Hungarian Power-to-Gas REKK Forum, Budapest Corvinus University, 12.02.2020 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Sektorenkopplung KW - Power-to-Gas Y1 - 2020 ER - TY - GEN A1 - Sterner, Michael T1 - Die Rolle von Wasserstoff in allen Sektoren T2 - Sektorenübergreifende Erkenntnisse zu PtX Fachforum "Wasserstoff Technologie, Prozesssicherheit und Regionalentwicklung", Kurt-Schwabe-Institut für Mess- und Sensortechnik Meinsberg e.V.) Meinsberg, 23.9.2020 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Sektorenkopplung KW - Wasserstoff Y1 - 2020 ER - TY - GEN A1 - Sterner, Michael T1 - Power-to-X im Kontext der Energiewende und des Klimaschutzes in Deutschland T2 - Hydrogen Dialogue H2.Bayern, 18.11.2020, Nürnberg Friedrich-Alexander-Universität KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Sektorenkopplung KW - Power-to-X Y1 - 2020 ER - TY - GEN A1 - Sterner, Michael T1 - Bedeutung des Klimaschutzes für die Wirtschaft in Ostbayern T2 - Veranstaltungsreihe der Freunde der OTH Regensburg e. V., Regensburg, Regensburg 25.11.2020 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Sektorenkopplung KW - Klimaschutz Y1 - 2020 ER - TY - GEN A1 - Sterner, Michael A1 - Schumm, Leon T1 - Netzpuffer – Speicher & Kraftwerke als virtuelle Leitungen für mehr Versorgungssicherheit und EE-Integration in Nord und Süd T2 - 7. Smart-Grid-Fachtagung WAGO, Hannover, 29. Sept. 2021 KW - Stromspeicher KW - Batterien KW - Netzpuffer KW - Stromnetz Y1 - 2021 ER - TY - GEN A1 - Sterner, Michael T1 - Vom Klimaschutz zum Wasserstoff in Verkehr und Industrie – jetzt regional handeln T2 - Kick-Off Workshop: HyExpert Wasserstoffmodellregion Fichtelgebirge, Wunsiedel, 22.09.2020 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Sektorenkopplung KW - Wasserstoff Y1 - 2020 ER - TY - GEN A1 - Sterner, Michael T1 - Wasserstoff als zentraler Baustein der Energiewende in Süddeutschland: Powerto- Gas und der rechtliche Rahmen T2 - 1. Wasserstofftag Süddeutschland, Um 29.10.2020 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Wasserstoff Y1 - 2020 ER - TY - GEN A1 - Sterner, Michael T1 - Warum wir Power-to-X für die Klimaneutralität und Mobilitätswende brauchen T2 - DECHEMA Fachforum Diesel: Mobilitätswende durch alternative Antriebe und Kraftstoffe:, Frankfurt 02.12.2020 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Sektorenkopplung KW - Power-to-X Y1 - 2020 ER - TY - GEN A1 - Sterner, Michael T1 - Grüner Wasserstoff - wo wir ihn brauchen für die Klimaneutralität T2 - Energiewendeforum Wasserstoff (Grüner Strom Label e. V.), Bonn, 21. September 2021 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Wasserstoff Y1 - 2021 ER - TY - GEN A1 - Sterner, Michael T1 - Wasserstoff – Energieträger der Zukunft T2 - BBA Forum, Passau 24.11.2020 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Wasserstoff Y1 - 2020 ER - TY - CHAP A1 - Sterner, Michael ED - Chen, Wei-Yin ED - Suzuki, Toshio ED - Lackner, Maximilian T1 - Power-to-Gas T2 - Handbook of Climate Change Mitigation and Adaptation N2 - This chapter provides an overview on the storage technology power-to-gas for the decarbonization of all energy sectors. Other than “negative emissions” with CCS or biomass, which have clear limits in potentials, costs and environmental benefits, storage and energy conversion technologies like power-to-gas and power-to-x enable the decarbonization by neutralizing the CO2 footprint of all energy services. Via the conversion of renewable electricity into chemical energy carriers like renewable hydrogen or renewable hydrocarbons, the existing fossil infrastructure with vast and sufficient storage and transport capacities can be used with carbon neutral renewable energy. After showing the demand for storage technologies, the technology components of power-to-gas are described, building the basis for the storage system power-to-gas itself that is described in detail, including efficiency, potential, CO2 emissions, and costs. In conclusion, a technical pathway of decarbonization including costs is described for the industrial nation of Germany and necessary policy frameworks are derived. Y1 - 2016 SN - 978-1-4614-6431-0 U6 - https://doi.org/10.1007/978-1-4614-6431-0_89-1 VL - 36 SP - 1 EP - 51 PB - Springer CY - New York, NY ER - TY - CHAP A1 - Sterner, Michael ED - Chen, Wei-Yin ED - Suzuki, Toshio ED - Lackner, Maximilian T1 - Power-to-Gas T2 - Handbook of Climate Change Mitigation and Adaptation N2 - This chapter provides an overview on the storage technology power-to-gas for the decarbonization of all energy sectors. Other than “negative emissions” with CCS or biomass, which have clear limits in potentials, costs and environmental benefits, storage and energy conversion technologies like power-to-gas and power-to-x enable the decarbonization by neutralizing the CO2 footprint of all energy services. Via the conversion of renewable electricity into chemical energy carriers like renewable hydrogen or renewable hydrocarbons, the existing fossil infrastructure with vast and sufficient storage and transport capacities can be used with carbon neutral renewable energy. After showing the demand for storage technologies, the technology components of power-to-gas are described, building the basis for the storage system power-to-gas itself that is described in detail, including efficiency, potential, CO2 emissions, and costs. In conclusion, a technical pathway of decarbonization including costs is described for the industrial nation of Germany and necessary policy frameworks are derived. Y1 - 2017 SN - 978-3-319-14408-5 U6 - https://doi.org/10.1007/978-3-319-14409-2_89 SP - 2775 EP - 2825 PB - Springer VS CY - Cham ET - 2 ER - TY - GEN A1 - Sterner, Michael T1 - Wie wird Deutschland klimaneutral? Neue Lösungen für erneuerbare Energieerzeugung T2 - Jahreskonferenz der Stiftung Nagelschneider zur Erforschung, München, 19.11.2021 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Klimaschutz Y1 - 2021 CY - München ER - TY - GEN A1 - Sterner, Michael T1 - Power-to-X for Europes Energy Transformation – Booster H2Global T2 - Hydrogen Online Workshop Conference (Mission Hydrogen), 25.03.2021 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Sektorenkopplung KW - Power-to-X Y1 - 2021 ER - TY - GEN A1 - Sterner, Michael T1 - Technologieausblick Solarstromspeicher T2 - Innovationsforum Photovoltaik, 18. Oktober 2021, Linz KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Solarstrom KW - Energiespeicher KW - Photovoltaik Y1 - 2021 ER - TY - BOOK ED - Sterner, Michael ED - Stadler, Ingo T1 - Energiespeicher - Bedarf, Technologien, Integration N2 - Die Autoren dieses Werkes geben einen umfassenden Überblick über die verschiedenen Aspekte der Energiespeicherung. Sie beschreiben zunächst die Bedeutung von Energiespeichern in der Energieversorgung und definieren ihre Rolle darin. Dann gehen sie auf den Speicherbedarf in der Strom-, Wärme- und Kraftstoffversorgung im Kontext der Energiewende ein. Im Hauptteil werden die verschiedenen Speichertechnologien ausführlich vorgestellt sowie ihre Vor- und Nachteile diskutiert. Praktische Anwendungsbeispiele und die Integration von Speichern über alle Energiesektoren hinweg runden das Buch ab. Zahlreiche Grafiken und Beispiele veranschaulichen das gesamte Feld der Energiespeicher und sind als Ergänzung mehrsprachig online in Farbe verfügbar. Die 2. Auflage enthält ein neues Kapitel zu den rechtlichen Rahmenbedingungen, neue Studien zum Speicherbedarf, Power-to-X für die chemische Industrie, neue LOHC- und Lageenergiespeicher sowie neueste Trends zu Kostenentwicklung und Batterieanwendungen. „Endlich ein umfassendes Buch zur Energiewende, das auch für technische Laien verständlich und inspirierend geschrieben ist." Franz Alt, Journalist und Buchautor „Das großartige Werk sei allen empfohlen, die sich wirklich für die Zukunft unseres Landes interessieren. Es zeigt auf eindrucksvolle Weise: Es wird nicht einfach, aber wir schaffen das.“ Prof. Dr. Harald Lesch, Physiker und Fernsehmoderator Y1 - 2017 SN - 978-3-662-48892-8 U6 - https://doi.org/10.1007/978-3-662-48893-5 PB - Springer CY - Berlin, Heidelberg ET - 2. korrigierte und ergänzte Auflage ER - TY - BOOK ED - Sterner, Michael ED - Stadler, Ingo T1 - Energiespeicher - Bedarf, Technologien, Integration N2 - Im Kontext der Energiewende sind Energiespeicher ein zentrales technisches, wirtschaftliches und energiepolitisches Thema.Die Autoren dieses kompakten Werkes geben einen umfassenden Uberblick Uber die verschiedenen Aspekte der Energiespeicherung. Sie beschreiben zunachst die Bedeutung von Energiespeichern in der Energieversorgung und definieren ihre Rolle darin. Dann gehen sie auf den Speicherbedarf in der Strom-, Warme- und Kraftstoffversorgung im Kontext der Energiewende ein. Im Hauptteil werden die verschiedenen Speichertechnologien ausfUhrlich vorgestellt sowie ihre Vor- und Nachteile diskutiert. Praktische Anwendungsbeispiele und die Integration von Speichern Uber alle Energiesektoren hinweg runden das Buch ab. Zahlreiche Grafiken und Beispiele veranschaulichen das gesamte Feld der Energiespeicher und sind als Erganzung samt Animationen online in Farbe verfUgbar.Die ZielgruppenDas Lehr- und Fachbuch wendet sich an Ingenieure, Wissenschaftler, Energieplaner und Energiewirtschaftler in Forschung und Industrie sowie an Studierende an Hochschulen und Universitaten in den Bereichen Maschinenbau, Verfahrenstechnik, Elektrotechnik und Energietechnik. KW - Energiespeicher KW - Energietechnik KW - Power-to-Gas KW - Speicherbedarf KW - Speicherintegration KW - Speichermarkt KW - Speichertechnologien KW - Systemintegration Y1 - 2014 SN - 978-3-642-37379-4 U6 - https://doi.org/10.1007/978-3-642-37380-0 PB - Springer CY - Berlin, Heidelberg ER - TY - CHAP A1 - Haslbeck, Matthias A1 - Brückl, Oliver T1 - Netzplanungsprozess zur dezentralen Nutzung von Blindleistungsquellen in Verteilungsnetzen T2 - Tagungsband der Fachtagung "Zukünftige Stromnetze für erneuerbare Energien" am 30./31. Januar 2018 in Berlin N2 - Das vom BMWi geförderte Forschungsprojekt SyNErgie (03/2015 bis 05/2018) beschäftigt sich mit der Weiterentwicklung von Netzplanungsprozessen [1]. Im Fokus steht dabei die Modellierung von Blindleistungsflüssen und die dezentrale Nutzung von Blindleistungsquellen (z. B. Wechselrichter, Ladedrosseln, Kondensatoren) in Mittelspannungsnetzen, über welche der Blindleistungshaushalt letztendlich beeinflusst werden soll. Diese Veröffentlichung konzentriert sich auf die konzipierte Erweiterung des Netzplanungsprozesses zur Einbindung von Blindleistungsquellen im Verteilungsnetz in ein Blindleistungsmanagement. Deren einzelne Phasen werden erläutert und anschließend die Netz-Sensitivitäts- und -Restriktionsanalyse anhand eines realen Mittelspannungsnetzes demonstriert. Abschließend werden mögliche Abschwächungs- und Verstärkungseffekte im Hinblick auf einen Blindleistungsabruf über mehrere Spannungsebenen hinweg diskutiert. Y1 - 2018 UR - https://www.fenes.net/wp-content/uploads/2019/03/SyNErgie_Paper_2018_Haslbeck_Netzplanungsprozess.pdf ER - TY - CHAP A1 - Berling, Andreas A1 - Haslbeck, Matthias A1 - Brückl, Oliver T1 - Interpretation und Relevanz verschiedener Blindleistungsarten für die Modellierung von Niederspannungsnetzen in der Netzplanung T2 - Tagungsband der Fachtagung "Zukünftige Stromnetze für erneuerbare Energien" am 30./31. Januar 2018 in Berlin Y1 - 2018 UR - https://www.fenes.net/wp-content/uploads/2019/03/SyNErgie_Paper_2018_Berling_Blindleistungsarten.pdf ER - TY - CHAP A1 - Rauch, Johannes A1 - Klitsman, Maksym A1 - Haslbeck, Matthias A1 - Brückl, Oliver T1 - Entwicklung von Methoden zur Prognose der Blindleistungsbilanz von Mittelspannungsnetzen zur Steuerungeines dezentralen Blindleistungsabrufs T2 - Tagungsband der Fachtagung Zukünftige Stromnetze 2019, Berlin Y1 - 2019 UR - https://www.fenes.net/wp-content/uploads/2019/03/SyNErgie_Paper_2018_Rauch_Blindleistungsprognose.pdf SP - 524 EP - 535 ER - TY - CHAP A1 - Strohmayer, Bernhard A1 - Brückl, Oliver T1 - Systemvergleich von Netzausbauoptionen in Niederspannungsnetzen T2 - 3. OTTI-Konferenz : zukünftige Stromnetze für Erneuerbare Energien, Berlin, 26./27. Januar 2016 N2 - Die Einhaltung der Spannungsbandgrenzen im Niederspannungsnetz durch die dezentrale Emspeisung von Erzeugungsanlagen ist oft der Grund für Netzausbaumaßnahmen. Dem Netzbetreiber stehen mittlerweile viele Losungsmaßnahmen zur Behebung des Spannungsbandproblems zur Verfügung Innovative Konzepte wie der regelbare Ortsnetztransformator (RONT) oder Blindleistungsregelung sind bereits serienreif und werden eingesetzt. Unklarheit herrscht oft noch darüber, welche Maßnahmen bzw Kombinationen langfristig wirtschaftlich günstig sind und sich hinsichtlich der Netzplanung als vorteilhaft erweisen. Ein Forschungsprojekt an der Ostbayerischen Technischen Hochschule Regensburg untersucht verschiedene Lösungsmaßnahmen systematisch, um sie wirtschaftlich, technisch und energetisch bewerten zu können. In 20 Netzen wird in diskreten Schritten die Integration von Erzeugungskapazität am Beispiel der PV simuliert. Der Zubau umfasst den Bereich von 0-100% des möglichen Dachflächenpotenzials. Nach jedem Zubauschritt wird die maximale Spannungsanhebung berechnet. Bei Überschreiten einer Spannungsanhebung in Höhe der in [VDE, FNN Erzeugungsanlagen am Niederspannungsnetz, VDE-AR-N 4105:2011-08] verankerten drei Prozentpunkte, oder der Stromtragfähigkeitsgrenze eines Betriebsmittels erfolgt ein Netzausbau. Dabei werden die Optionen RONT, die Parallelverkabelung, drei Stufen des Einspeisemanagements (Spitzenkappung auf 85%, 70% und 55%), die Blindleistungsregelung (cosφ(P)), der Zubau von zusätzlichen Ortsnetzstationen und die Verwendung von Strangreglern untersucht. Je kleiner das Ortsnetz, desto stärker bedingt sich die Kostenentwicklung durch die gewählte Primärmaßnahme. Klassischer Netzausbau ist in kleinen Netzen meist teurer als der Einsatz von RONT oder Strangreglern. In größeren Netzen können Parallelverkabelung oder zusätzliche ONS zu günstigen Ausbaupfaden führen. Maßnahmen die anfangs nahezu keine Investition in Netzbetriebsmittel benötigen (Einspeisemanagement, Blindleistungsregelung) sind initial mit Abstand am günstigsten. Im Mittel günstiger als RONT sind anfangs auch Verkabelung und Strangregler, jedoch bei höherer Ergebnisstreuung. Bereits nach fünf Perioden liegen die mittleren Gegenwartswerte für starke Spitzenkappung, Blindleistungsregelung und zusätzliche ONS häufig über der Maßnahme RONT. Die geringste Kostenstreuung tritt beim Einsatz von RONT auf. Mittel- und langfristig liegen die Mediane fast aller Primärmaßnahmen über den wahrscheinlich auftretenden Kosten für Strangregler und RONT. Bei Erschließung von zusätzlichen 25% des theoretisch maximalen Potenzials nach Erreichen der NAK betragen die Kosten bei RONT-Einsatz ca. 125/kWp. Parallelverkabelung verursacht rd. 45, Blindleistungsregelung rd. 55 €/kWp Mehrkosten. Bei 50% des Ausbaupotenzials führen Parallelverkabelung und Blindleistungsregelung mit im Mittel 50 bzw. 75 €/kWp sogar zu noch höheren Mehrkosten. Für 20 GW PV-Leistung in der Niederspannung bedeutet dies über 1 Mrd. Zusatzkosten. RONT und Strangregler erweisen sich zudem kostenrobust gegenüber unerwartet ausbleibendem Kapazitätszubau. Analysen dazu und Ergebnisse für andere Zinssätze und Zeitskalen befinden sich in [INA, Informationsportal: Regelbare Ortsnetztransformatoren, 2015. http://ront.info]. KW - Blindleistungsregelung KW - Netzausbau KW - Netzbetreiber KW - Netzmittel KW - Netzplanung KW - Netztransformator KW - Niederspannung KW - Niederspannungsnetz KW - Spannungsanhebung KW - Stromtragfähigkeit KW - Systemvergleich KW - Verkabelung Y1 - 2016 SN - 978-3-943891-63-8 SP - 256 EP - 261 CY - Regensburg ER - TY - CHAP A1 - Jentsch, Mareike A1 - Trost, Tobias A1 - Sterner, Michael T1 - Optimal Use of Power-to-Gas Energy Storage Systems in an 85% Renewable Energy Scenario T2 - Energy Procedia N2 - In future energy systems with high shares of fluctuating renewable energy generation, electricity storage will become increasingly important for the utilization of surplus energy. The Power-to-Gas (PtG) technology is one promising option for solving the challenge of long-term electricity storage and is theoretically able to ease situations of grid congestion at the same time. This article presents the perspectives of PtG in an 85% renewable energy scenario for Germany, quantifying an economic optimum for the PtG capacity as well as an optimized spatial PtG deployment. KW - Deutschland KW - Elektrizität KW - Energieproduktion KW - Energiespeicher KW - erneuerbare Energie KW - Langzeitarchivierung KW - Methan KW - optimale Nutzung KW - PtG (Power-to-Gas) Y1 - 2014 U6 - https://doi.org/10.1016/j.egypro.2014.01.180 SN - 1876-6102 VL - 46 SP - 254 EP - 261 PB - Elsevier ER - TY - CHAP A1 - Stadler, Ingo A1 - Bauer, Franz A1 - Budt, Marcus A1 - Heindl, Eduard A1 - Wolf, Daniel T1 - Mechanische Energiespeicher T2 - Energiespeicher - Bedarf, Technologien, Integration Y1 - 2017 SN - 978-3-662-48893-5 SN - 978-3-662-48892-8 U6 - https://doi.org/10.1007/978-3-662-48893-5_9 SP - 495 EP - 577 PB - Springer Vieweg CY - Berlin ; Heidelberg ET - 2. Auflage ER - TY - CHAP A1 - Thema, Martin A1 - Bellack, Annett A1 - Weidlich, Tobias A1 - Huber, Harald A1 - Karl, Jürgen A1 - Sterner, Michael ED - Held, Jörgen T1 - Optimizing biological CO2-methanation in a trickle-bed reactor BT - the ORBIT-Project T2 - 6th International Conference on Renewable Energy Gas Technology, 20-21 May 2019, Malmö, Sweden. Conference proceedings KW - Biologische Methanisierung KW - Power-to-Gas KW - Erneuerbare Energien KW - Rieselbett-Bioreaktor KW - Archaeen Y1 - 2019 SP - 93 EP - 94 PB - Renewable Energy Technology International AB CY - Lund, Sweden ER - TY - GEN A1 - Sterner, Michael A1 - Thema, Martin T1 - Technologies status and perspectives of Power-to-Gas in connection with seasonal underground storage T2 - European Workshop on Underground Energy Storage, Paris 07.11.2019 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Sektorenkopplung KW - Power-to-Gas Y1 - 2019 ER - TY - GEN A1 - Sterner, Michael T1 - Megathema Wasserstoff: Power-to-X im Kontext der Energiewende und des Klimaschutzes in Deutschland T2 - IRES Symposium, Berlin 18.11.2020 KW - Erneuerbare Energien KW - Wasserstoff KW - Klimaneutralität KW - Power-to-X KW - Energiewende KW - Sektorenkopplung Y1 - 2020 ER - TY - GEN A1 - Sterner, Michael T1 - The role of green H 2 + Power-to-X in the German Energy Transition T2 - First Brazilian-German Green Hydrogen Congress, Brasilia 06.10.2020 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Sektorenkopplung KW - Wasserstoff KW - Power-to-X Y1 - 2020 ER - TY - GEN A1 - Sterner, Michael T1 - Die Grenzen des Wasserstoff-Hypes T2 - 1. Mitteldeutscher Wasserstoffkongress, 2. November 2021, Leuna CCE Kulturhaus KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Wasserstoff Y1 - 2021 ER - TY - JOUR A1 - Schiek, Roland T1 - Excitation of nonlinear beams: from the linear Talbot effect through modulation instability to Akhmediev breathers JF - Optics express N2 - The smooth transition between stable, Talbot-effect-dominated and modulationally unstable nonlinear optical beam propagation is described as the superposition of oscillating, growing and decaying eigenmodes of the common linearized theory of modulation instability. The saturation of the instability in form of breather maxima is embedded between eigenmode growth and decay. This explains well the changes of beam characteristics when the input intensity increases in experiments on modulation instability and breather excitation in spatial-spatial experimental platforms. An increased accuracy of instability gain measurements, a variety of interesting nonlinear beam scenarios and a more selective and well-directed breather excitation are demonstrated experimentally. KW - DYNAMICS KW - FIBER KW - GENERATION KW - PEREGRINE SOLITON KW - SPATIAL SOLITONS KW - WAVE-GUIDE Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-26049 N1 - Corresponding author: Roland Schiek VL - 29 IS - 10 SP - 15830 EP - 15851 PB - Optica Publishing Group CY - Washington, DC, USA ER - TY - CHAP A1 - Sefl, Ondrej A1 - Prochazka, Radek A1 - Haller, Rainer A1 - Monkman, Gareth J. T1 - Alternative Approach to Optical Detection of Partial Discharges in Air T2 - 2021 IEEE Conference on Electrical Insulation and Dielectric Phenomena (CEIDP): 12-15 Dec. 2021, Vancouver, BC, Canada N2 - This article compares the standard electrical method of partial discharge detection with a novel optical detection method based on silicon photomultipliers. A third, complementary, single-loop antenna method is added to represent the ultra-high frequency method commonly used in gas-insulated switchgear/lines. A trio of air-insulated electrode designs that simulate the fundamental fault/discharge types in gaseous insulation (protrusion – corona discharge, floating conductive particle, surface discharges) are employed. Phase-resolved partial discharge activity patterns are compiled for each electrode design. The patterns are analyzed using spatial statistics and the interpretation of the obtained data trends explained by means of an example. Ultimately, the consistency and reliability of discharge detection by the optical methods for each fault/discharge type are evaluated, and suggestions for improvement are made. KW - gas insulated switchgear KW - loop antennas KW - partial discharges KW - photomultipliers KW - reliability KW - statistical analysis KW - surface discharges Y1 - 2021 SN - 978-1-6654-1907-9 U6 - https://doi.org/10.1109/CEIDP50766.2021.9705350 SN - 2576-2397 SP - 324 EP - 327 PB - IEEE ER - TY - CHAP A1 - Brückl, Oliver A1 - Wildfeuer, M. A1 - Schächinger, J. T1 - Systemdienstleistungen durch Biogasanlagen T2 - Biogas in der Landwirtschaft - Stand und Perspektiven: 7. FNR/KTBL-Onlinetagung 29.-30.09.2021, Darmstadt KW - Biogasanlage Y1 - 2021 SN - 978-3-945088-83-8 SP - 92 EP - 101 CY - Darmstadt ER - TY - CHAP A1 - Jupke, Michael A1 - Reindl, Andrea A1 - Meier, Hans A1 - Niemetz, Michael ED - Pinker, Jiří T1 - Bidirectional DC-DC Converter with Digital Droop Parameterization T2 - 26th 2021 International Conference on Applied Electronics (AE): 7-8 Sept. 2021 Pilsen, Czech Republic N2 - The key for decentralized battery systems is a robust and communication-less control strategy for autonomous power sharing of parallel-connected DC-DC converters. Battery systems improve the reliability and quality of power supply in renewable energy systems and enable power supply for off-grid, mobile applications, including islanded grids, home storage, and electric vehicles. In many cases, components with different electrical properties require different voltage levels. An adaptation is consequently essential and is normally implemented in DC grids for the batteries via bidirectional DC-DC converters. The power flow in both directions can thus be ensured. To achieve a power distribution in parallel connected DC-DC converters, a droop control in the form of a virtual internal resistor can be used. This paper presents a novel approach of a DC-DC converter with a digitally parameterizable droop resistor, whose voltage regulation is based on an analog operational amplifier circuit to ensure low delays and robustness. The droop resistor is adjusted with a microcontroller, which offers the possibility to apply a higher-level control for load sharing via an interface. Mathematical correlations are used to clearly define the parameters of the control. Furthermore, the circuit was completely simulated and tested in the hardware setup. The shown results verify the functionality and indicate only minor deviations. Therefore, this circuit is important for future use in distributed battery systems. KW - battery storage plants KW - DC-DC power convertors KW - power convertors KW - distributed power generation KW - microcontrollers KW - voltage regulators KW - voltage control KW - power generation control KW - power grids Y1 - 2021 SN - 978-80-261-0972-3 U6 - https://doi.org/10.23919/AE51540.2021.9542920 SP - 1 EP - 6 PB - Institute of Electrical and Electronics Engineers ER - TY - CHAP A1 - Herbold, Florian A1 - Reindl, Andrea A1 - Meier, Hans A1 - Niemetz, Michael A1 - Krämer, Stefan ED - Kubátová, Hana ED - Fišer, Petr ED - Borecký, Jaroslav T1 - Secure Software Updates: Challenges and Solutions for Embedded IoT Systems T2 - Proceedings of the 9th Embedded Systems Workshop: July 1-3, 2021 Horomerice, Czech Republic N2 - The invention of the internet made the development of intelligent networking of millions of embedded systems possible. This enabled smart buildings, power grids and cities as well as applications in the fields of health, agriculture and industry. These systems frequently perform safety-critical applications and operations. This makes it urgent to protect these sensible systems as effectively as possible. Especially firmware updates are often the weak point in the systems. If unauthorised persons gain access to the system during the update, malware can be injected or sensitive data can be read and stolen. This paper describes the challenges of secure firmware updates. To protect an embedded system from potential attackers, the concepts integrity, authenticity and confidentiality have to be adhered during the update process. Otherwise, there is an increased risk of modifying or reverse engineering the firmware image. Likewise, inadequately protected software can enable the installation of third-party firmware as well as the installation of firmware on a third-party system. Threat prevention is presented with solutions derived from functional safety and IT security. Aspects of protection against errors in the transmission of updates and against attacks aiming to compromise the system are explained. Finally, a possible sequence of a secure update process is examined in detail for a real embedded system implementation. For this purpose, the preparation, transmission and installation of a firmware update in the bootloader are discussed KW - Bootloader KW - Cryptograph KW - Embedded systems KW - Firmware Update KW - IoT KW - Safety, Security KW - Software Protection Y1 - 2021 UR - https://www.researchgate.net/publication/354995594_Secure_Software_Updates_Challenges_and_Solutions_for_Embedded_IoT_Systems SN - 978-80-01-06858-8 SP - 5 EP - 13 ER - TY - CHAP A1 - Reindl, Andrea A1 - Singer, Thomas A1 - Meier, Hans A1 - Niemetz, Michael A1 - Park, Sangyoung T1 - Framework to Test DC-DC Converters Developed for a Decentralized Battery Management System T2 - 2021 International Conference on Applied Electronics (AE): 7-8 Sept. 2021, Pilsen, Czech Republic N2 - DC- DC converters control the power flow and thus the power distribution between the components on different voltage levels. They are essential for (dis)charging batteries and influence the safety and stability of the entire battery management system (BMS). Therefore, testing the functionality and the reliability of DC-DC converters is crucial. This is especially true for decentralized battery management systems (DBMS), where multiple nodes communicate to collectively control the system. The used DC-DC converters are modified to parameterize them during operation via microcontroller interfaces. Integrating the communication into the control loop requires an analysis of the control behavior due to additional delays. Therefore, this paper proposes a framework to test DC-DC converters considering the control and communication perspectives. The response time, the control accuracy and stability of these DC-DC converters, e.g., under continuous and abrupt load changes, are measured in automated tests. The dedicated software framework simulates the DBMS and stimulates the hardware components (e.g. electronic loads, data acquisition) via respective interfaces (CAN, RS232). This allows the test of various DC-DC converters with flexibly adaptable load and power generation profiles. An initial application validates the test framework by verifying the aforementioned aspects and thus the applicability of a DC-DC converter within the DBMS. KW - Batteries KW - Battery management system KW - Battery management systems KW - Control systems KW - DC-DC converter KW - DC-DC power converters KW - decentralized control KW - hardware in the loop testing KW - object oriented programming KW - Power system stability KW - Python KW - Stability analysis KW - system testing KW - Time measurement Y1 - 2021 U6 - https://doi.org/10.23919/AE51540.2021.9542882 SP - 1 EP - 6 PB - IEEE ER - TY - CHAP A1 - Schiek, Roland T1 - Parameter Scans for Characterization of Nonlinear Beam Propagation T2 - Proceedings OSA Nonlinear Optics 2021: 9-13 August 2021, Washington, DC, United States N2 - Intensity-dependent beam propagation inside nonlinear media is difficult to characterize without cutting back — and destroying — the sample. Observing the output dependent on system parameters can provide information on the beam dynamics along the path. Y1 - 2021 SN - 978-1-943580-97-2 U6 - https://doi.org/10.1364/nlo.2021.ntu1b.5 PB - Optica Publishing Group, OSA CY - Washington, D.C. ER - TY - CHAP A1 - Reindl, Andrea A1 - Meier, Hans A1 - Niemetz, Michael A1 - Park, Sangyoung T1 - Decentralized Battery Management System with Customized Hardware Components T2 - IEEE 19th Student Conference on Research and Development (SCOReD), Sustainable Engineering and Technology towards Industry Revolution: 23-25 Nov. 2021, Kota Kinabalu, Malaysia N2 - With an increasing number of sold electric vehicles (EVs), a large number of used batteries will be at disposal. How to deal with these resources is one of the major challenges in reducing the environmental impact of batteries throughout their entire life cycle. Heterogeneous cell parameters due to the different usage histories are a challenge for second-life use. The effort and cost of remanufacturing required to test and assemble a new battery pack is a further concern. Systems that combine battery packs/modules without full reassembly offer advantages such as cost and reusability. A decentralized battery management system (DBMS) provides a suitable architecture for such systems involving different types of batteries. In this paper, an architecture for a decentralized, battery state-dependent control is shown. The proposed DBMS supports various types of batteries, is scalable and flexibly adaptable for a wide range of applications. Despite the significant advantages, there are increased requirements to meet for the hardware implementation and the applied control strategies. Therefore, the necessary hardware components and their requirements are described and the hardware implementations are provided. KW - battery fitness KW - Battery management system KW - Battery management systems KW - bidirectional power flow KW - Computer architecture KW - Costs KW - DC-DC power converters KW - decentralized control KW - Electric vehicles KW - Hardware KW - load sharing KW - Microprocessors KW - Renewable energy sources KW - second life battery Y1 - 2021 U6 - https://doi.org/10.1109/SCOReD53546.2021.9652737 SP - 350 EP - 355 PB - IEEE ER - TY - CHAP A1 - Ooi, Boon Yaik A1 - Lee, Wai-Kong A1 - Schubert, Martin J. W. A1 - Ooi, Yu-Wei A1 - Chin, Chee-Yang A1 - Woo, Wing-Hon T1 - A Flexible and Reliable Internet-of-Things Solution for Real-Time Production Tracking T2 - IEEE Industrial Electronics and Applications Conference (IEACon): 22.11.2021 - 23.11.2021, Penang, Malaysia N2 - The concept of Industrial Revolution 4.0 (IR4.0) has sparked the urgency of many manufacturers to revisit their manufacturing processes and search for opportunities to further improved their production output. Unfortunately, it is difficult to improve a process with inadequate data. Many of the SMEs in developing countries are still using manufacturing machines from the yesteryears which do not have computational and connectivity capabilities. Therefore, we developed an end-to-end Internet-of-Things (IoT) solution, which reliably tracks the production performance of manufacturing machines. This paper elaborates on the designs and the rationale behind it. As of the writing of this paper, our IoT system has been deployed in real manufacturing environment and has been running for approximately 90 days on a 24/7 basis without data lost. KW - industry 4.0 KW - IoT KW - production tracking KW - Smart Manufacturing Y1 - 2021 SN - 978-1-7281-9253-6 U6 - https://doi.org/10.1109/IEACon51066.2021.9654672 SP - 270 EP - 275 PB - IEEE ER - TY - CHAP A1 - Schubert, Martin J. W. A1 - Lee, Wai-Kong A1 - Ooi, Boon Yaik T1 - Quantization and Sampling Effects in Fast Digitally Controlled Switch-Mode DC/DC Buck Converters T2 - 2021 IEEE Industrial Electronics and Applications Conference (IEACon): 22.11.2021 - 23.11.2021, Penang, Malaysia N2 - Software-defined control of DC/DC switch mode power converters features unequaled flexibility compared to analog control. For fast switching converters as recently used for low power applications, digital control may cause steady-state oscillations known as limit cycles. This effect based on a quantized duty cycle is compared to other aberrations such as output ripple voltage, which is inherent to any pulse-width modulator. A distinction is made between DC and AC errors. The latter are divided into synchronous and asynchronous output voltage disturbances. Synchronous AC errors are composed of the switching frequency and its harmonics. KW - aberrations due to digitization KW - digital pulse-width modulation (DPWM) KW - low power DC/DC buck conversion KW - output voltage sampling Y1 - 2021 SN - 978-1-7281-9253-6 U6 - https://doi.org/10.1109/IEACon51066.2021.9654272 SP - 56 EP - 61 PB - IEEE ER - TY - CHAP A1 - Hänninen, Risto A1 - Niemetz, Michael A1 - Schoepe, Wilfried T1 - Transition to turbulence in oscillatory superflows T2 - ETC 2013 - 14th European Turbulence Conference 2020: 2 September 2013 - 4 September 2013, Lyon, France N2 - The flow of superfluid helium-4 at very low temperatures around an oscillating microsphere has been studied in detail. At small oscillation amplitudes the drag force is linear in velocity amplitude. Above a critical velocity amplitude vc a transition from potential flow to turbulent flow is signaled by a large and nonlinear drag force that scales as (v2 - v2 c ), where vc is found to be independent of temperature (below 1 K) and of driving force. Interestingly, the critical velocity is found to scale as vc ~ √κω, where κ = h/m ≈ 10−7 m2/s (h is Planck's constant and m is the mass of a helium-4 atom) is the circulation quantum of the superfluid vortices and ω/2π is the oscillation frequency ranging from about 120 Hz to 700 Hz. We also observe slightly above vc that the flow pattern is unstable and switches intermittently between potential flow and turbulence. From time series recorded at constant drive and temperature we have investigated the statistical properties of this switching phenomenon. In this talk the universal law vc ~ √κω will be discussed in detail. It can be derived theoretically in various ways: firstly, from a qualitative but very general argument based on the "superfluid Reynolds number" Rs = vl/κ where v is the flow velocity and l is a characteristic length scale, secondly, and in more detail, from Kopnin's equation of the time dependence of the vortex line density, and, finally, we have obtained this law rigorously by dynamical scaling of the equations of motion of vortex dynamics. Y1 - 2020 UR - http://etc14.ens-lyon.fr/openconf/modules/request.php?module=oc_proceedings&action=view.php&a=Accept&id=17 ER - TY - CHAP A1 - Reindl, Andrea A1 - Meier, Hans A1 - Niemetz, Michael ED - Brinkmann, André ED - Karl, Wolfgang ED - Lankes, Stefan ED - Tomforde, Sven ED - Pionteck, Thilo ED - Trinitis, Carsten T1 - Scalable, Decentralized Battery Management System Based on Self-organizing Nodes T2 - Architecture of computing systems - ARCS 2020: 33rd international conference, Aachen, Germany, May 25-28, 2020, proceedings N2 - Due to the transition to renewable energy sources and the increasing share of electric vehicles and smart grids, batteries are gaining in importance. Battery management systems (BMSs) are required for optimal, reliable operation. In this paper, existing BMS topologies are presented and evaluated in terms of reliability, scalability and flexibility. The decentralisation of BMSs and associated advantages are shown. A scalable, reconfigurable BMS based on a distributed architecture of self-organized, locally controlled nodes is proposed. For distributed system control, producers, batteries and consumers each are equipped with a local microcontroller based control unit, which monitors and controls the local parameters with its own computing and communication resources. Features, advantages and challenges to overcome of the proposed approach are described. KW - Availability Decentralized control KW - Battery management systems KW - Controller Area Network KW - distributed management KW - fault tolerant control KW - Multi-microcomputer system KW - Reconfigurable architectures KW - Renewable energy sources KW - Scalability KW - Topology Y1 - 2020 SN - 978-3-030-52793-8 U6 - https://doi.org/10.1007/978-3-030-52794-5_13 VL - 12155 SP - 171 EP - 184 PB - Springer International Publishing CY - Cham ER - TY - CHAP A1 - Hayakawa, Shuhei A1 - Al-Falouji, Ghassan A1 - Schickhuber, Gerald A1 - Mandl, Roland A1 - Yoshida, Takahiro A1 - Hangai, Seiichiro T1 - A Method of Toothbrush Position Measurement using AR Markers T2 - 2020 IEEE 2nd Global Conference on Life Sciences and Technologies (LifeTech): 10-12 March 2020, Kyoto, Japan N2 - Appropriate daily brushing of the teeth is important for preventing oral diseases. Therefore, a personal assistant for assessing and coaching appropriate toothbrushing is needed. Herein, a three-dimensional toothbrush position measurement method using augmented reality (AR) markers is proposed. The AR markers are detected via a brushing video captured using a smartphone camera. The AR markers are installed on each surface of a dodecahedron attached at the rear end of the toothbrush. This report describes the proposed method, the resulting toothbrush position measurement accuracy, and the optimal number of markers needed for an accurate measurement of the position. KW - AR marker KW - position measurement KW - toothbrush Y1 - 2020 U6 - https://doi.org/10.1109/LifeTech48969.2020.1570619103 SP - 91 EP - 93 PB - IEEE ER - TY - CHAP A1 - Hiyama, Toru A1 - Sehr, Armin A1 - Yoshida, Takahiro A1 - Hangai, Seiichiro T1 - Text/Language-Independent Unknown Speaker Rejection Method Using LSP Codes T2 - IEEE 9th Global Conference on Consumer Electronics (GCCE 2020): 13-16 Oct. 2020, Kobe, Japan N2 - Scam phone calls pretending relatives have become a major social problem. However, current countermeasure against such scam phone calls stays only enlightenment activities although there is a limited number of technical measures in telephones. In this study, we have proposed a text-independent unknown speaker rejection method which recognizes whether a known speaker or an unknown speaker on receiving a call. In this method, we used a line spectral pair (LSP) spectrogram as the feature and a convolutional neural network (CNN) as the identification engine. From the evaluated results, the proposed method recognized known/unknown speakers with the false acceptance rate (FAR) of 13.1% in Japanese speech and 25.2% in German speech, respectively. Y1 - 2020 U6 - https://doi.org/10.1109/GCCE50665.2020.9291835 ER - TY - CHAP A1 - Forster, Eva A1 - Mayer, Matthias A1 - Rabindranath, R. A1 - Bentz, Alexander A1 - Böse, Holger A1 - Shamonin (Chamonine), Mikhail A1 - Monkman, Gareth J. T1 - Surface Control Magneto-Active Polymers (MAP) T2 - EuroEAP 2011, First international conference on Electromechanically Active Polymer (EAP) transducers & artificial muscles, Pisa, 8-9 June N2 - Smart materials change their properties with external energy supply. Besides the known ferro-fluids and Magneto Rheological Fluid (MRF) also the Electro Active Polymer (EAP) and Magneto Rheological Elastomer (MRE) belong to these intelligent materials. The latest generation of magnetic elastomers represents a new class of composite materials. This consists of small magnetized particles which are sized in the micron or even nanometer range that in turn is bounded in a highly elastic rubber matrix. These materials are very often called MRE. Only recently, it has managed to develop these materials even further, so that very soft composite materials with a young?s modulus up to 10 kPa are possible. These soft polymers could be named magneto-active polymers. The combination of polymers with magnetic materials show novel and often enhanced properties. A precisely controllable young?s modulus and hardness, giant and non-homogeneous deformation behavior and rapid response to the magnetic field opens up new possibilities for various applications. Since MAP represent a very new technology, the behavior of these materials as a function of their composition and external conditions so far are not yet sufficiently understood. Therefore, some fundamental studies are necessary. In this paper, the mechanical surface properties are studied using a micro hardness meter. This work shows the possibility to control mechanical properties at the surface of MAP with new developed magnetic systems. Y1 - 2011 ER - TY - JOUR A1 - Petchartee, Somrak A1 - Monkman, Gareth J. T1 - Optimisation of Prehension Force through Tactile Sensing JF - Journal of Advanced Manufacturing Technology Y1 - 2007 SN - 2289-8107 PB - Universiti Teknikal Malaysia Melaka ER - TY - CHAP A1 - Petchartee, Somrak A1 - Monkman, Gareth J. T1 - Optimisation of Prehension Force through Tactile Sensing T2 - Proc. International Conference on Engineering & ICT 2007 (ICEI 2007), Malaysia Y1 - 2007 ER - TY - CHAP A1 - Pohlt, Clemens A1 - Schlegl, Thomas A1 - Wachsmuth, Sven T1 - Weakly-Supervised Learning for Multimodal Human Activity Recognition in Human-Robot Collaboration Scenarios T2 - 2020 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS): October 25-29, 2020, Las Vegas, NV, USA (virtual) N2 - The ability to synchronize expectations among human-robot teams and understand discrepancies between expectations and reality is essential for human-robot collaboration scenarios. To ensure this, human activities and intentions must be interpreted quickly and reliably by the robot using various modalities. In this paper we propose a multimodal recognition system designed to detect physical interactions as well as nonverbal gestures. Existing approaches feature high post-transfer recognition rates which, however, can only be achieved based on well-prepared and large datasets. Unfortunately, the acquisition and preparation of domain-specific samples especially in industrial context is time consuming and expensive. To reduce this effort we introduce a weakly-supervised classification approach. Therefore, we learn a latent representation of the human activities with a variational autoencoder network. Additional modalities and unlabeled samples are incorporated by a scalable product-of-expert sampling approach. The applicability in industrial context is evaluated by two domain-specific collaborative robot datasets. Our results demonstrate, that we can keep the number of labeled samples constant while increasing the network performance by providing additional unprocessed information. KW - Activity recognition KW - Collaboration KW - Intelligent robots KW - reliability KW - Service robots KW - Synchronization Y1 - 2020 U6 - https://doi.org/10.1109/IROS45743.2020.9340788 SP - 8381 EP - 8386 PB - IEEE ER - TY - CHAP A1 - Pohlt, Clemens A1 - Schlegl, Thomas A1 - Wachsmuth, Sven T1 - Human Work Activity Recognition for Working Cells in Industrial Production Contexts T2 - 2019 IEEE International Conference on Systems, Man and Cybernetics (SMC), 6-9 Oct. 2019, Bari, Italy N2 - Collaboration between robots and humans requires communicative skills on both sides. The robot has to understand the conscious and unconscious activities of human workers. Many state-of-the-art activity recognition algorithms with high performance rates on existing benchmark datasets are available for this task. This paper re-evaluates appropriate architectures in light of human work activity recognition for working cells in industrial production contexts. The specific constraints of such a domain is elaborated and used as prior knowledge. We utilize state-of-the-art algorithms as spatiotemporal feature encoders and search for appropriate classification and fusion strategies. Furthermore, we combine keypoint-based with appearance-based approaches to a multi-stream recognition system. Due to data protection rules and the high effort of data annotation within industrial domains only small datasets are available that reflect production aspects. Therefore, we use transfer learning approaches to reduce the dependency on data volume and variance in the target domain. The resulting recognition system achieves high performance for both singular person action and human-object interaction. KW - Activity recognition KW - Pose estimation KW - Robots KW - Task analysis KW - Three-dimensional displays KW - Two dimensional displays Y1 - 2019 U6 - https://doi.org/10.1109/SMC.2019.8913873 SP - 4225 EP - 4230 ER - TY - CHAP A1 - Köhler, Thomas A1 - Rösel, Birgit T1 - Experiences with a new Digitalized Concept for Teaching Control Theory as Minor Subject at a University of Applied Science T2 - 2019 IEEE Global Engineering Education Conference (EDUCON), 8-11 April 2019, Dubai, United Arab Emirates N2 - This paper presents experiences with a digitalized concept for teaching control theory as minor subject with an integrated approach for lectures, exercises and practical sessions in the department of electrical engineering at the OTH Regensburg. The concept uses activating methods like blended learning and possibilities of digitalization of teaching implementing Just in Time Teaching and Peer Instruction. The basis for the new concept is the idea of constructive alignment. Furthermore this paper presents feedback from the students along with an accompanying scientific research over several semesters focusing on the development over past semesters. KW - Blended Learning KW - Computer aided instruction KW - constructive alignment KW - Control engineering education KW - Control theory KW - Distance learning KW - Educational courses KW - Electrical engineering education KW - Just in Time Teaching KW - teaching text Y1 - 2019 U6 - https://doi.org/10.1109/EDUCON.2019.8725217 SP - 593 EP - 600 PB - IEEE ER - TY - JOUR A1 - Schiek, Roland T1 - Nonlinear refractive index in silica glass JF - Optical Materials Expres N2 - The third-order nonlinear susceptibility of silica glass is measured via self-phase modulation in standard single mode fibers at a wavelength of 1550 nm. To minimize the influence of polarization state changes along the propagation only meter-long fibers were investigated. With pulse durations of picoseconds a quasi-instantaneous nonlinearity with ultrafast electronic and fast nuclear-vibration contributions produces under conditions of negligible dispersion a classic and clean nonlinear phase shift following exactly the shape of the pulse power. The complex pulse envelope was retrieved from frequency optical gating spectrograms. The nonlinear fiber parameter γ could be determined with an accuracy of 3.7 percent. Considering the mode field structure and the doping influence the nonlinear refractive index of silica glass as the fiber base material was found to be n 2 =2.22⋅10 −16 cm 2 W±6.0% for picosecond-long pulses. Comparing nonlinear phase shifts from linear and circular polarized light a nuclear-vibration contribution to the cubic fiber nonlinearity of 25 percent was estimated. Y1 - 2023 U6 - https://doi.org/10.1364/ome.489520 N1 - Corresponding author: Roland Schiek VL - 13 IS - 6 SP - 1727 EP - 1740 PB - Optica ER - TY - CHAP A1 - Grab, Robin A1 - Rauch, Johannes A1 - Götz, Rebekka A1 - Brückl, Oliver A1 - Eichner, Stefan A1 - Engel, Bernd T1 - Q-Dynamik: Blindleistungsstellgeschwindigkeiten im Verteilnetz T2 - Zukünftige Stromnetze: 27.-28. Januar 2021, 03.-04. Februar 2021, Tagungsunterlagen N2 - Mit der Energiewende geht eine starke Dezentralisierung der Energieeinspeisung einher. So sind im Deutschland des Jahres 2020 rund 31.000 Windenergieanlagen (WEA) in Betrieb, während bei der Solarenergie vor kurzem die zweimillionste Photovoltaik-Anlage (PVA) installiert wurde. Fast alle diese dezentralen Energieressourcen (DER) sind nach den Einspeiserichtlinien der Vergangenheit und der Gegenwart in der Lage, Blindleistung bereitzustellen, um die Spannung im Netz zu regeln und zum Blindleistungsausgleich beizutragen. Weitere potentielle dezentrale Blindleistungsquellen wie Blockheizkraftwerke, Kompensationsanlagen und perspektivisch sogar Verbraucher und Speicher sind im Verteilnetz zu finden. Durch den stetigen Rückbau konventioneller Großkraftwerke, welche dem Übertragungsnetz bisher als Blindleistungsquellen zur Verfügung standen, bedarf es einer Untersuchung mit der Fragestellung, in welchem Maß die neue Erzeugungslandschaft auch in diesem Feld als Ersatz dienen kann. Ein mögliches Hindernis für einen breitangelegten Einsatz von DER zu Zwecken des spannungsebenenübergreifenden Blindleistungsmanagements ist mangelndes Wissen über die Regeldynamik dieser verteilten Blindleistungsquellen. Übertragungs- und Verteilnetzbetreiber, die DER aktiv für Blindleistungsausgleich oder statische Spannungsregelung einsetzen, geben in der Regel ihre Blindleistungsanforderungen in kleineren Stufen mit erheblichen Latenzzeiten zwischen zwei Schritten weiter. Befürchtet wird, dass schnellere Sprünge in der Blindleistungsvorgabe zu instabilen Betriebszuständen oder anderweitigen Fehlfunktionen im Netz führen können. Eine genauere Kenntnis der dynamischen Fähigkeiten vorhandener Blindleistungsquellen sowie der Auswirkungen auf die Netzstabilität und den Netzschutz könnte dazu beitragen, die Geschwindigkeit der Blindleistungsbereitstellung zu optimieren und somit temporäre Spannungsschwankungen und -verluste zu minimieren und die Spannungsstabilität insgesamt zu verbessern. Durch eine entsprechende Regelungs- und Einsatzstrategie kann ein optimales Zusammenspiel der verschiedenen Technologien zur Deckung der Blindleistungsbedarfe für unterschiedliche Zeitbereiche erzielt werden. Hierfür ist eine genaue Kenntnis der Blindleistungsstellgeschwindigkeiten und des dynamischen Regelverhaltens erforderlich. Dieser Beitrag stellt dazu Ergebnisse aus dem Forschungsprojekt „Q-Integral“ vor. Um die relevanten Zeitkonstanten der Blindleistungsbereitstellung vollständig aufzuführen, werden zunächst typische Kommunikationszeiten für die Übermittlung von Sollwerten diskutiert. Anschließend werden Untersuchungen zu theoretischen und praktischen Reaktionszeiten verschiedener Blindleistungsquellen vorgestellt. Dafür werden verschiedene Technologien wie Umrichter für PVA, Batteriespeicher und WEA sowie Synchrongeneratoren, die bei thermischen Kraftwerken die dominierende Technologie sind, betrachtet. Abschließend werden diese Werte mit realen Blindleistungsstellgeschwindigkeiten von ausgedehnten Wind- und Solarkraftwerken verglichen. KW - Blindleistung KW - Blindleistungsmanagement KW - Q-Dynamik KW - Blindleistungsquellen KW - Verteilungsnetz Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-58762 SN - 978-3-948176-12-9 SP - 46 EP - 55 PB - Conexio-PSE GmbH CY - Pforzheim ER - TY - JOUR A1 - Rauch, Johannes A1 - Brückl, Oliver T1 - Achieving Optimal Reactive Power Compensation in Distribution Grids by Using Industrial Compensation Systems JF - Electricity N2 - This paper presents a method for integrating industrial consumers owning compensation systems as alternative reactive power sources into grid operating processes. In remuneration, they receive a market-based provision of reactive power. The aim is to analyze the potential of reactive power compensation systems of industrial companies connected to medium-voltage (10 kV–30 kV) AC grids in order to increase the reactive power ability of distribution grids. Measurement methods and reactive power potential results of six industrial companies are presented to characterize the amount and temporal availability of their reactive power potential. The presented approach for using the decentralized reactive power potential is a centralized reactive power control method and is based on optimal power flow (OPF) calculations. An optimization algorithm based on linear programming is used to coordinate a reactive power retrieval tuned to the actual demand. The influencing quantities are the current grid status (voltage and load flow capacity reserves at grid nodes and power lines) and the current reactive power potential of the reactive power sources. The compensation impact of six measured industrial companies on an exemplary medium-voltage grid is shown by an application example. KW - Blindleistung KW - Blindleistungsmanagement KW - Industriebetriebe KW - Optimal Power Flow KW - Reactive Power Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-59139 N1 - Corresponding author: Johannes Rauch VL - 4 IS - 1 SP - 78 EP - 95 PB - MDPI CY - Basel ER - TY - JOUR A1 - Kahl, Matthias A1 - Krause, Veronika A1 - Hackenberg, Rudolf A1 - Ul Haq, Anwar A1 - Horn, Anton A1 - Jacobsen, Hans-Arno A1 - Kriechbaumer, Thomas A1 - Petzenhauser, Michael A1 - Shamonin (Chamonine), Mikhail A1 - Udalzow, Anton T1 - Measurement system and dataset for in-depth analysis of appliance energy consumption in industrial environment JF - tm - Technisches Messen N2 - To support a rational and efficient use of electrical energy in residential and industrial environments, Non-Intrusive Load Monitoring (NILM) provides several techniques to identify state and power consumption profiles of connected appliances. Design requirements for such systems include a low hardware and installations costs for residential, reliability and high-availability for industrial purposes, while keeping invasive interventions into the electrical infrastructure to a minimum. This work introduces a reference hardware setup that allows an in depth analysis of electrical energy consumption in industrial environments. To identify appliances and their consumption profile, appropriate identification algorithms are developed by the NILM community. To enable an evaluation of these algorithms on industrial appliances, we introduce the Laboratory-measured IndustriaL Appliance Characteristics (LILAC) dataset: 1302 measurements from one, two, and three concurrently running appliances of 15 appliance types, measured with the introduced testbed. To allow in-depth appliance consumption analysis, measurements were carried out with a sampling rate of 50 kHz and 16-bit amplitude resolution for voltage and current signals. We show in experiments that signal signatures, contained in the measurement data, allows one to distinguish the single measured electrical appliances with a baseline machine learning approach of nearly 100% accuracy. KW - appliance monitoring KW - DAQ KW - NILM Y1 - 2019 U6 - https://doi.org/10.1515/teme-2018-0038 VL - 86 IS - 1 SP - 1 EP - 13 PB - De Gruyter ER - TY - JOUR A1 - Bakaev, V. V. A1 - Snarskii, Andrei A. A1 - Shamonin (Chamonine), Mikhail T1 - The permeability and remanent magnetization of a randomly inhomogeneous two-phase medium JF - Technical Physics N2 - A randomly inhomogeneous composite consisting of two, ferromagnetic and nonmagnetic (para-or diamagnetic), phases is considered. The dependence of the effective permeability of the composite on the concentration of the ferromagnetic phase and on the applied magnetic field is found for the case of the negligible hysteresis loop. When the hysteresis loop is appreciable, the remanent magnetization as a function of the ferromagnet concentration is calculated. KW - Magnetic Field KW - Permeability KW - Hysteresis Loop KW - Remanent Magnetization KW - Applied Magnetic Field Y1 - 2002 U6 - https://doi.org/10.1134/1.1435901 VL - 47 SP - 125 EP - 128 PB - Springer ER - TY - JOUR A1 - Snarskii, Andrei A. A1 - Zhenirovskyy, M. I. A1 - Shamonin (Chamonine), Mikhail T1 - The effective properties of macroscopically nonuniform ferromagnetic composites: Theory and numerical experiment JF - Journal of Experimental and Theoretical Physics N2 - Various theoretical models (self-consistent field, local linearization, and percolation theory methods and an analytic solution of the linear problem for an ordered medium) for calculating the magnetostatic properties of two-phase composites containing one ferromagnetic phase were considered. The concentration and field dependences of the effective magnetic permeability were found. A method for determining the coercive force and remanent magnetization as functions of the ferromagnetic phase concentration was suggested. Numerical experiments were performed for composites with a periodic distribution of circular inclusions. The results were compared with the analytically calculated effective magnetic permeability. KW - Numerical Experiment KW - Remanent Magnetization KW - Field Dependence KW - Coercive Force KW - Magnetic Permeability Y1 - 2003 U6 - https://doi.org/10.1134/1.1545385 VL - 96 SP - 66 EP - 77 PB - Springer ER - TY - JOUR A1 - Shamonin (Chamonine), Mikhail A1 - Snarskii, Andrei A. A1 - Zhenirovskyy, M. I. T1 - Effective magnetic permeability of ferromagnetic composites. Theoretical description and comparison with experiment JF - NDT & E International N2 - Two analytical methods based on the so-called local linearization of magnetostatic properties of composite materials with ferromagnetic inclusions in a non-magnetic matrix are described. These methods are applied to the experimental data obtained in Gorkunov et al. [Russ. J. Nondestruct. Test. 3 (2001) 186]. A qualitative agreement is obtained for the concentration values reported in that paper and a quantitative agreement is achieved at slightly different value of concentration. The conclusions are supported by direct numerical modeling. KW - Material characterization KW - Ferromagnetic composites KW - Magnetostatic properties Y1 - 2004 U6 - https://doi.org/10.1016/j.ndteint.2003.08.001 VL - 37 IS - 1 SP - 35 EP - 40 PB - Elsevier ER - TY - JOUR A1 - Filippov, O. A1 - Ringhofer, K. H. A1 - Shamonin (Chamonine), Mikhail A1 - Shamonina, Ekaterina A1 - Kamshilin, A. A. A1 - Nippolainen, E. A1 - Sturman, B. I. T1 - Polarization properties of light-induced scattering in Bi12TiO20 crystals: theory and experiment for diagonal geometry JF - Journal of the Optical Society of America B N2 - Illumination of ac-biased photorefractive Bi12TiO20 crystals with a coherent light beam results in the development of strong nonlinear scattering. Theoretically and experimentally we investigate the angular and polarization characteristics of the scattered light for the diagonal ([1̲1̲1]) optical configuration and different polarization states of the pump. A satisfactory understanding of the observed scattering properties is achieved for most of the cases investigated. Y1 - 2003 U6 - https://doi.org/10.1364/JOSAB.20.000677 VL - 20 IS - 4 SP - 677 EP - 684 PB - Optica Publishing Group ER - TY - JOUR A1 - Lukyanets, S. A1 - Snarskii, Andrei A. A1 - Shamonin (Chamonine), Mikhail A1 - Bakaev, V. V. T1 - Calculation of magnetic leakage field from a surface defect in a linear ferromagnetic material: an analytical approach JF - NDT & E International N2 - A novel analytical approach for calculating the magnetic leakage field from surface defects is proposed and demonstrated for the case of a linear ferromagnetic material. The novelty of the theory is that it relates the distribution of induced magnetic charges to the surface shape. An excellent agreement between the analytical and numerical results is shown. The functional relations between different magnetic field components are discussed. KW - Magnetic methods KW - Flux leakage KW - Mathematical model KW - Defects Y1 - 2003 U6 - https://doi.org/10.1016/S0963-8695(02)00071-3 VL - 36 IS - 1 SP - 51 EP - 55 PB - Elsevier ER - TY - JOUR A1 - Snarskii, Andrei A. A1 - Shamonin (Chamonine), Mikhail A1 - Zhenirovskyy, M. I. T1 - Effective properties of macroscopically non-uniform ferromagnetic composite materials BT - Theory and numerical experiment JF - Zhurnal Eksperimental'noj i Teoreticheskoj Fiziki - Journal of Experimental and Theoretical Physics (JETP) Y1 - 2003 VL - 123 IS - 1 SP - 79 EP - 92 PB - Akademija Nauk SSSR CY - Moscow ER - TY - JOUR A1 - Filippov, O. A1 - Ringhofer, K. H. A1 - Shamonin (Chamonine), Mikhail A1 - Shamonina, Ekaterina A1 - Kamshilin, A. A. A1 - Nippolainen, E. A1 - Sturman, B. I. T1 - Polarization properties of light-induced scattering in Bi_12TiO_20 crystals BT - theory and experiment for diagonal geometry JF - Journal of the Optical Society of America B N2 - Illumination of ac-biased photorefractive Bi12TiO20 crystals with a coherent light beam results in the development of strong nonlinear scattering. Theoretically and experimentally we investigate the angular and polarization characteristics of the scattered light for the diagonal ([1̲1̲1]) optical configuration and different polarization states of the pump. A satisfactory understanding of the observed scattering properties is achieved for most of the cases investigated. Y1 - 2003 U6 - https://doi.org/10.1364/josab.20.000677 VL - 20 IS - 4 PB - Optica Publishing Group ER - TY - JOUR A1 - Lukyanets, S. A1 - Snarskii, Andrei A. A1 - Shamonin (Chamonine), Mikhail A1 - Bakaev, V. V. T1 - Calculation of magnetic leakage field from a surface defect in a linear ferromagnetic material: an analytical approach JF - NDT & E International N2 - A novel analytical approach for calculating the magnetic leakage field from surface defects is proposed and demonstrated for the case of a linear ferromagnetic material. The novelty of the theory is that it relates the distribution of induced magnetic charges to the surface shape. An excellent agreement between the analytical and numerical results is shown. The functional relations between different magnetic field components are discussed. KW - Magnetic methods KW - Flux leakage KW - Mathematical model KW - Defects Y1 - 2003 U6 - https://doi.org/10.1016/s0963-8695(02)00071-3 VL - 36 IS - 1 SP - 51 EP - 55 PB - Elsevier ER - TY - JOUR A1 - Bakaev, V. V. A1 - Snarskii, Andrei A. A1 - Shamonin (Chamonine), Mikhail T1 - The permeability and remanent magnetization of a randomly inhomogeneous two-phase medium JF - Technical Physics N2 - A randomly inhomogeneous composite consisting of two, ferromagnetic and nonmagnetic (para-or diamagnetic), phases is considered. The dependence of the effective permeability of the composite on the concentration of the ferromagnetic phase and on the applied magnetic field is found for the case of the negligible hysteresis loop. When the hysteresis loop is appreciable, the remanent magnetization as a function of the ferromagnet concentration is calculated. Y1 - 2002 U6 - https://doi.org/10.1134/1.1435901 VL - 47 IS - 1 SP - 125 EP - 128 PB - Springer ER - TY - THES A1 - Hartweg, Johanna T1 - Analyse des Einflusses verschiedener Arbeitspunkte auf die wirkleistungsabhängige Spannungssensitivität an einem Mittelspannungsnetzknoten N2 - Im Rahmen dieser Arbeit erfolgt die Untersuchung der wirkleistungsabhängigen Spannungssensitivität an den Knoten eines Mittelspannungsnetzstranges. Hierfür wird eine Reihe von Arbeitspunkten durch die Variation der Wirkleistungsentnahmen bzw. Einspeisungen an den Netzknoten sowie des Verschiebungsfaktors und der Spannungssollwertvorgabe am Bilanzknoten erzeugt. Die Ergebnisse zeigen eine direkte Abhängigkeit von der Spannung des untersuchten Netzknotens. Hierbei steigt die Sensitivität bei fallenden Spannungswerten. Diese können sowohl durch Wirk- und Blindleistungsbelastungen als auch durch eine veränderte Referenzspannung am Umspannwerk bedingt werden. Darüber hinaus liegt eine Beeinflussung durch die Wirkleistungsbelastung und deren Verteilung über den Netzstrang hinweg vor. Je höher die Belastung der Leitung bis zum Knoten der Flexibilität ausfällt sowie je stärker sich die Last hin zu diesem Punkt verlagert, desto höher ist die Sensitivität. Dies gilt ebenfalls für Arbeitspunkte mit gleichbleibender Spannung in den betrachteten Knoten. Des Weiteren wird die Anpassung eines multiplen linearen Regressionsmodells vorgenommen. Dieses ermöglicht eine Abschätzung der Sensitivitätswerte durch die Kenntnis einiger, die Belastungssituation des Netzes bestimmender Parameter. KW - Netzmodell KW - Sensitivitätsanalyse KW - Arbeitspunktabhängigkeit Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-55648 CY - Regensburg ER - TY - CHAP A1 - Schrimer, M A1 - Putz, C. A1 - Monkman, Gareth J. ED - McConnell, Lynn T1 - Boron-Silicone-Oxide Polymers T2 - Boron: advances in research and applications Y1 - 2021 SN - 9781685072315 SN - 1685072313 U6 - https://doi.org/10.52305/AFKU5564 SP - 117 EP - 179 PB - Nova Science Publishers CY - New York, NY ER - TY - RPRT A1 - Gerhards, Christoph A1 - Weber, Urban A1 - Klafka, Peter A1 - Golla, Stefan A1 - Hagedorn, Gregor A1 - Baumann, Franz A1 - Brendel, Heiko A1 - Breyer, Christian A1 - Clausen, Jens A1 - Creutzig, Felix A1 - Daub, Claus-Heinrich A1 - Helgenberger, Sebastian A1 - Hentschel, Karl-Martin A1 - von Hirschhausen, Christian A1 - Jordan, Ulrike A1 - Kemfert, Claudia A1 - Krause, Harald A1 - Linow, Sven A1 - Oei, Pao-Yu A1 - Pehnt, Martin A1 - Pfennig, Andreas A1 - Präger, Fabian A1 - Quaschning, Volker A1 - Schneider, Jens A1 - Spindler, Uli A1 - Stelzer, Volker A1 - Sterner, Michael A1 - Wagener-Lohse, Georg A1 - Weinsziehr, Theresa T1 - Klimaverträgliche Energieversorgung für Deutschland – 16 Orientierungspunkte T2 - Diskussionsbeiträge der Scinetists for Future ; 7 N2 - Als fairer Beitrag Deutschlands zur Einhaltung der globalen 1,5-Grad-Grenze werden 16 Orientierungspunkte für eine klimaverträgliche Energieversorgung vorgestellt. Es wird davon ausgegangen, dass hierfür die deutschen energiebedingten CO2-Emissio­nen in etwa 15 Jahren weitgehend auf Null sinken müssen. Energieeinsparung hilft, den notwendigen Ausbau von regenerativen Erzeugungskapazitäten zu verringern. Der Verkehrssektor kann ebenso wie die Bereiche Prozess- und Gebäudewärme hier­zu wesentlich beitragen. Die Kernenergie ist mit großen Risiken belastet und kann nicht hinreichend schnell aufgebaut werden. Biomasse in Form von Energie­pflan­zen zu nutzen, ist ineffizient und steht im Konflikt mit anderen Arten der Land­nut­zung. Importe klimaneutral erzeugter Energieträger in sehr großem Umfang er­for­dern extrem große Investitionen im Ausland. Sie sind eine ungesicherte Option auf die Zukunft. Entscheidend ist daher der ausreichend schnelle Ausbau von Photovoltaik (PV) und Wind­kraft in Deutschland. Schätzungsweise kann der Elektrizitätsbedarf im Jahr 2030 z.B. durch den Ausbau auf ca. 350 GW PV und ca. 150 GW Windkraft nahe­zu voll­ständig regenerativ gedeckt werden. Damit ließe sich eine zum großen Teil elek­tri­fizierte Mobilität und Wärmeversorgung betreiben und ein Teil des benö­tig­ten "grü­nen" Wasserstoffs in Deutschland bereitstellen. Hierfür ist ein jähr­licher Zu­bau von durchschnittlich ca. 30 GW PV und ca. 9 GW Windkraft nötig. Dies ist ca. sechs- (PV) bzw. dreimal (Wind) so hoch wie bisher vorgesehen und verlangt eine ge­sell­schaft­liche Kraftanstrengung. Ein weiter verzögerter Ausbau müsste mit noch deut­lich größeren gesellschaftlichen Anstrengungen für drastische Energieeinspa­run­gen oder Importe erneuerbarer Energie ausgeglichen werden. Insgesamt könnte dies noch deutlich schwieriger zu realisieren sein, als ein ambitionierter Ausbau. Da der Auf­bau der Kapazitäten mehrere Jahre erfordert, ist es möglich nachzusteuern, z. B. wenn erkennbar wird, dass sich ein ausreichend großer globaler Markt für Importe ent­wi­ckelt. Bis dahin ist es aus Verantwortung gegen­über der Zukunft und im Sinne des Pariser Vertrages empfehlenswert, die hier genannten Ausbauziele zu verfol­gen. Grüner, also aus erneuerbaren Energien hergestellter Wasserstoff und daraus abge­lei­tete Syntheseprodukte sind für die Dekarbonisierung von Industrieprozessen, den Flug- und Schiffsverkehr sowie für die Absicherung der Energieversorgung bei Dun­kel­flauten nötig. Ohne die genannten Ausbauziele für Wind und Solar noch drastisch weiter zu erhöhen, stehen diese Produkte für Straßenverkehr und Wärmeversor­gung jedoch nicht in ausreichenden Mengen zur Verfügung. Techniken zum Aus­gleich zwischen Elektrizitätsangebot und -nachfrage sind verfügbar und sollten recht­zeitig auf- bzw. ausgebaut werden. Hierzu gehören: Stromaustausch mit den Nach­barländern, Flexibilisierung des Verbrauchs und Energiespeicherung. Für deren Inte­gration sowie den Ausbau der Netze sollten zügig verbesserte rechtliche Rah­men­bedingungen geschaffen werden. Die Kosten eines klimaverträglichen Energiesystems sind mittel- bis langfristig nicht hö­her als im derzeitigen System. Gleichzeitig entstehen Arbeitsplätze und Export­chan­cen durch Aufbau, Betrieb und Wartung einer regenerativen Energieversorgung in Deutschland und die energetische Gebäudesanierung. Die politischen Rahmenbe­din­gungen entscheiden, ob eine klimaverträgliche Energieversorgung Deutschlands ge­lingt. T2 - Climate-friendly energy supply for Germany - 16 points of orientation KW - Climate KW - Energy System KW - Renewable Energies Y1 - 2021 U6 - https://doi.org/10.5281/zenodo.4409334 ER - TY - CHAP A1 - Roesel, Birgit A1 - Schmidt, Nina T1 - Ein umfassendes Konzept für einen Grundkurs Regelungstechnik unter Verwendung aktivierender Lehrmethoden T2 - Tagungsband AALE 2019: autonome und intelligente Systeme in der Automatisierungstechnik, 16. Fachkonferenz, 28. Februar - 1. März 2019, Heilbronn N2 - Im Beitrag wird das Konzept für einen 6 SWS Grundkurs der Regelungstechnik an der Fakultät Elektro- und Informationstechnik der OTH Regensburg vorgestellt. Ein wesentliches Merkmal des Konzeptes ist die konsequente und durchgehende Anwendung der Idee des constructive alignment auch für die Konzipierung einer kompetenzorientierten Prüfung. Ausgangspunkt der Entwicklung des neuen Konzepts war die Definition von Lernzielen für das gesamte Modul, die dann für jede einzelne Lehrveranstaltung detailliert wurden. Im Ergebnis gibt es einen genauen Plan für die Abfolge der einzelnen Lehrveranstaltungen zur Theorievermittlung, der Übungen und der Praktika sowie der jeweils zu erreichenden Lernziele. Basierend auf der Definition von Lernzielen wurde ein Drittel der Lehrveranstaltungen zur Theorievermittlung mit einem Blended learning Ansatz konzipiert. Für diesen müssen die Studierenden vor der eigentlichen Lehrveranstaltung einen spezifischen Lehrtext lesen und Fragen dazu beantworten. Sie haben außerdem die Möglichkeit, selbst Fragen an die Dozentin zu stellen. Basierend auf diesem Rücklauf kann die Dozentin den Inhalt der Präsenzphase auf die jeweilige Studierendengruppe anpassen und dadurch spezifisch auf die Anforderungen dieser Gruppe reagieren. Durch diese Just-in-Time Teaching (JiTT) Methode oder auch inverted classroom Methode wird auch den unterschiedlichen Vorkenntnissen der Studierenden Rechnung getragen. Die übrigen Lehrveranstaltungen zur Theorievermittlung werden als klassische Lehrveranstaltungen durchgeführt. Auch in diesen werden aktivierende Lehrmethoden wie die Peer Instruction oder Clicker Befragungen eingesetzt. Peer Instruction stellt nach eine ideale Ergänzung zu JiTT dar. Die Übungseinheiten und Praktika dienen dem weiteren Kompetenzerwerb im Sinne der komplexeren Lernziele. Insbesondere die Praktika fokussieren jeweils auf einen spezifischen Effekt, der gezielt gefestigt werden soll. Zusätzlich wurde als weitere Innovation eine sogenannte Landkarte der Regelungstechnik – also eine Visualisierung der Themengebiete der Regelungstechnik – erstellt. Diese dient regelmäßig in den Lehrveranstaltungen zur Unterstützung zusammenfassender Darstellungen und soll außerdem den Studierenden helfen, mehr Überblick über die Themengebiete und ihren Zusammenhang zu geben. Zum Abschluss des Beitrags werden einige Erfahrungen aus der Umstellungsphase vorgestellt – Ergebnisse aus diversen Befragungen und Rückmeldungen wie auch Auswertungen von Fragebögen. KW - Elektrotechnik KW - Fakultät KW - Informationstechnik KW - Innovation KW - Just-in-Time KW - Landkarte KW - Praktikum KW - Rechnung KW - Regelungstechnik KW - Visualisierung Y1 - 2019 UR - https://www.vde-verlag.de/proceedings-de/564860040.html SN - 978-3-8007-4860-0 SP - 1 EP - 9 PB - VDE-Verlag CY - Berlin ER - TY - CHAP A1 - Rösel, Birgit T1 - A concept of a mainly digitalized course on control theory including problembased practical units and digital supported exams T2 - HEAd'20: Sixth International Conference on Higher Education Advances, June 2 - June 5 2020, Valencia (Spain) N2 - This paper decribes the concept of a course on control theory as a minor subject in the department of electrical engineering at the OTH Regensburg. The basis for a new concept is the idea of contructive alignment. The whole teaching module is devided in two blocks. The first block contains the teaching of the knowledge about control theory with an integrated approach for lectures, exercises and practical sessions. In the second block the students attent a practical work package to have the possibility to applicate and deepen their knowledge. To foster active participation the students are asked to document and reflect their work with the course context in an electronic portfolio. The exam of this module consists of three parts with respect to the different competencies obtained during the module. This concept develops not only the knowledge on control theory but personal and social competencies which are of growing interest. The aim of the paper is to present the idea of the concept. Following papers will illustrate the development process and the results obtained later on. Y1 - 2020 U6 - https://doi.org/10.4995/HEAd20.2020.11112 ER - TY - CHAP A1 - Goetz, Rebecca A1 - Rauch, Johannes A1 - Brückl, Oliver ED - Schulz, Detlef T1 - Techno-economic analysis of reactive power sources T2 - NEIS 2021, Conference on Sustainable Energy Supply and Energy Storage Systems: Hamburg, 13.-14. September 2021 N2 - This paper presents different options to provide reactive power in electricity grid systems. Since conventional power plants are being phased out and the reactive power demand tends to increase, alternative technologies are needed to cover it. reactive power sources are being defined and specified in this submission. A technical evaluation and an economic analysis of selected reactive power sources are carried out, based on interviews with manufacturers and operators. As well a multifactorial techno-economic comparison of the evaluated reactive power sources is presented. The technical analysis addresses reactive power control-ranges, stochastic parameters, lifespans, electrical losses and dynamics of re-active power sources. It states that power electronics allow faster setpoint changes than mechanical technologies can achieve, but at the same time this is associated with the highest electrical losses of the reactive power sources considered here. Considering the economic analysis, relative investment costs per reactive power of conventional compensation systems turn out to be the most cost-efficient. With regard to the multifactorial techno-economic comparison, it is im-portant not only to standardize on reactive power that can be provided, but also to include the additional system-relevant properties of technologies in the evaluation as well as the costs in operation. Y1 - 2021 UR - https://ieeexplore.ieee.org/document/9698281/ SN - 978-3-8007-5651-3 SP - 286 EP - 291 PB - VDE-Verlag ER - TY - CHAP A1 - Rauch, Johannes A1 - Brückl, Oliver T1 - Konzeptionierung netzplanerischer Prozessansätze zur Ermittlung von Blindleistungskapazitäten zum Ausgleich des Blindleistungsbedarfs in einer Netzregion T2 - Tagungsband Tagung Zukünftige Stromnetze 26./27. Januar 2022 (online) N2 - Um einen sicheren und zuverlässigen Stromnetzbetrieb zu gewährleisten, muss die Spannung im Grundfall als auch bei ungeplanten Ausfällen in definierten Bereichen gehalten werden. Im Übertragungsnetz wird hierfür bisher Blindleistung hauptsächlich aus Blindleistungskompensationsanlagen und konventionellen Großkraftwerken eingesetzt. Zukünftig wird nach §12h EnWG eine marktgestützte Beschaffung dieser Dienstleistung zur Spannungsregelung vorgeschrieben. Zugleich verändert sich der Blindleistungsbedarf der Netzbetriebsmittel durch die Integration erneuerbarer Energieanlagen und der Elektromobilität sowie durch den Netzausbau bei Übertragungs- und Verteilungsnetzbetreibern. Es bedarf somit angepasster Netzbetriebs- und Netzplanungskonzepte für ein technisch effizientes und wirtschaftlich günstiges Blindleistungsmanagement. Dieser Beitrag beschäftigt sich damit, Prozessansätze und Methodiken für ebendieses in der Netzplanung aufzuzeigen, um erforderliche Blindleistungskapazitäten unter minimalen Gesamtkostenaufwand und unter Berücksichtigung einer effizienten Blindleistungsbedarfsdeckung zu bestimmen. Dabei liegt der Fokus verstärkt in der Bedarfsanalyse. KW - Blindleistung KW - Blindleistungsmanagement KW - Netzplanungsprozesse KW - Spannungshaltung KW - Optimierungsverfahren Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-58665 SN - 978-3-948176-16-7 SP - 117 EP - 126 PB - Conexio-PSE GmbH CY - Pforzheim ER - TY - CHAP A1 - Schweiberer, Philipp A1 - Rauch, Johannes A1 - Brückl, Oliver T1 - Entwicklung eines Regelkonzeptes für einen optimierten Blindleistungsabruf auf Basis von Blindleistungspotentialanalysen bei Industriebetrieben im Mittelspannungsnetz T2 - Tagungsband Tagung Zukünftige Stromnetze 26./27. Januar 2022 (online) N2 - Im Zuge der Energiewende ergibt sich ein Wandel in der Struktur des Elektrizitätsversorgungsnetzes. Die Verschiebung der Erzeugungsleistung von konventionellen Großkraftwerken in höheren Netzebenen hin zu dezentralen erneuerbaren Energieanlagen in niedrigeren Netzebenen resultiert sowohl in bidirektionalen Lastflüssen als auch in schwankenden Einspeisecharakteristiken. Des Weiteren folgen durch den Wegfall von Großkraftwerken als Blindleistungsquellen Leistungsdefizite in der Übertragungsnetzebene, die kompensiert werden müssen. Daraus resultieren Herausforderungen an einen sicheren und zuverlässigen Betrieb der Verteil- und Übertragungsnetze. Neue Konzepte müssen für die Erbringung von Blindleistung entwickelt werden, es soll mehr Blindleistung aus dem Verteilungsnetz zur Verfügung gestellt werden, um die Systemstabilität zu wahren. Im Rahmen des Projektes Q-Integral wird das Thema „Blindleistung“ (Q) ganzheitlich untersucht. Es werden dazu verschiedene Erbringungsoptionen für Blindleistung hinsichtlich technischer und wirtschaftlicher Potentiale untersucht, die in ein funktionales und effizientes Blindleistungsmanagement eingebracht werden. Die Untersuchungsansätze dafür sind sowohl spannungsebenen-übergreifend als auch netzbetreiber-übergreifend. Ein Ansatzpunkt des Projektes ist die Betrachtung der Blindleistungsbereitstellung von Industriebetrieben. Dazu wird das Potential von Betrieben, die an das Verteilnetz angeschlossen sind und Blindleistung durch Kompensations- oder Erzeugungsanlagen bereitstellen können, untersucht. Ziel ist es, das gesicherte und maximale induktive sowie kapazitive Potential zu bestimmen. Das gesicherte kapazitive Potential kann genutzt werden, um Aussagen darüber zu treffen, wie stark dem Spannungsfall im vorgelagerten Netz zu Starklastzeiten entgegengewirkt werden kann. Anhand des gesicherten induktiven Potentials kann ein Spannungsanstieg während Schwachlastzeiten ausgeglichen werden kann. In diesem Beitrag werden Ergebnisse aus dem Projekt Q-Integral vorgestellt. Dazu werden zuerst die Berechnungsgrundlagen der induktiven und kapazitiven Blindleistungspotentiale aufgezeigt und die Ergebnisse der Berechnungen vorgestellt. Die gewonnen Ergebnisse entstammen aus Messungen an einem Industriebetrieb mit Blindleistungskompensationsanlagen (BKA), den entsprechenden Reglern der Anlagen und einer installierten Kompensationsleistung von 1600 kvar. Sowohl die Lastgänge als auch das Schaltverhalten der einzelnen Kompensationsanlagen liegen den Berechnungen zugrunde. Um den Austausch der Blindleistung an der Übergabestelle des Betriebs zum Mittelspannungsnetz netzdienlich einzustellen, bedarf es eines geeigneten Regelkonzepts, das neben den BKAs auch weitere Q-Quellen berücksichtigt. Deshalb wird abschließend ein Regelkonzept vorgestellt, das den technisch-optimierten Blindleistungsabruf unter Berücksichtigung mehrerer Blindleistungsquellen behandelt. KW - Blindleistung KW - Blindleistungsmanagement KW - Blindleistungsquellen KW - Blindleistungspotentiale KW - Industriebetriebe Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-58704 SN - 978-3-948176-16-7 SP - 224 EP - 233 PB - Conexio-PSE GmbH CY - Pforzheim ER - TY - CHAP A1 - Rauch, Johannes A1 - Brückl, Oliver T1 - Analysis of the correlation behavior between local available information to the overall reactive power of a medium-voltage grid group T2 - Applied Research Conference - ARC 2017, 7 July 2017 München N2 - The initiated energy transition leads to extensive changes in the supply of energy. The increasing use of renewable energy causes a shift of the produced power from centralized conventional power plants to decentralized energy plants. Because of this redistribution and the related change of load-flows, new challenges and problems for distribution system operators appear. This includes the integration of new loads and plants into the existing power grid and the guarantee of a high supply security and quality. It also includes strengthened requirements for the use and provision of reactive power. The project “SyNErgie” (“Systemoptimierendes Netz- und Energiemanagement für Verteilungsnetze der Zukunft“) deals with the development of a new reactive power management, which gets embedded in grid planning and controlling processes. One focus of the project is on the integration of decentralized energy plants (DEPs) to the reactive power management. The aim is to develop a decentralized and self-sufficient reactive power control system, which only works with local available information (measures). Therefore is no necessity of a complex communication system to the grid control center. Self-controlled Q-controller in the DEPs get characteristic curves and control the reactive power sources with local measurements (e.g. current, voltage, effective power). This new reactive power control management aims for the reactive power compensation in order to increase the integration capacity of loads and plants in a grid [2]. In order to generate characteristic curves for DEPs, it is necessary to analyze the correlation behavior between the local available measurements at the DEPs and the overall-Q-behavior of the grid group at the transformer. In that regard, influencing quantities should be considered. The aim is to involve und evaluate all relevant influencing quantities in order to determine energy plants and certain operating points, in which the correlation behavior and the prediction for the overall-Q-behavior are sufficient. The next step is to develop a model that fits these correlation behaviors and generate characteristic curves. One method to generate characteristic curves for the Q-controllers is regression analysis. The developed Q-control-system with the characteristic curves will be tested, evaluated and optimized in a following field test in cooperation with distribution system operators. KW - Mittelspannungsnetz KW - Blindleistungsmanagement KW - Blindleistung KW - Integration Erneuerbare Energien KW - Potentialerschließung Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-58712 SP - 224 EP - 230 CY - München ER - TY - RPRT A1 - Sterner, Michael A1 - Schumm, Leon A1 - Rank, Daniel A1 - Hofrichter, Andreas T1 - Intelligente Netzpuffer : Abschlussbericht (24.01.2021) KW - Stromspeicher KW - Batterien KW - Netzpuffer KW - Stromnetz Y1 - 2021 N1 - unveröffentlichter Abschlussbericht ER - TY - CHAP A1 - Schubert, Martin J. W. A1 - Höfflinger, Bernd A1 - Zingg, René P. T1 - A New Analytical Charge Model for the Dual-Gate-Controlled Thin-Film SOI MOSFET T2 - Superlattices and Microstructures N2 - An analytical model for dual-gate-controlled SOI MOSFETs is presented, assuming uniformly doped p-silicon films. It is restricted to electron inversion layers and depletion regions, neglecting hole densities. It allows to account for the spatial description of electronic quantities in the silicon film. Due to the non-linearities of the semiconductor equations the model parameters must be extracted iteratively. Some applications are presented to demonstrate the usefulness of the model. Y1 - 1990 U6 - https://doi.org/10.1016/0749-6036(90)90218-V VL - 7 IS - 4 SP - 323 EP - 326 PB - Elsevier ER - TY - CHAP A1 - Schubert, Martin J. W. A1 - Blödel, J. A1 - Conradi, P. A1 - Lafosse, P. A1 - Nebel, W. A1 - Neusser, S. A1 - Ryba, M. A1 - Schröder, D. T1 - Extending EDIF for Technology Data T2 - EDIF World Conference, 1989, San Jose, CA, USA, 11.-14. September Y1 - 1989 ER - TY - THES A1 - Schubert, Martin J. W. T1 - Eindimensionale Modellierung von SOI MOSFETs Y1 - 1991 CY - Hamburg ER - TY - JOUR A1 - Schubert, Martin J. W. A1 - Höfflinger, Bernd A1 - Schröder, D. A1 - Zingg, René P. T1 - 1D Modeling of SOI MOSFETs Using Distinct Quasi-Fermi Potentials JF - Microelectronic Engineering N2 - Distinct electron and hole quasi-Fermi potentials, øf,n and øf,p, are included into a one-dimensional SOI MOSFET model that accounts for finite inversion and depletion layer thicknesses. The inclusion of øf,n, øf,p in the nonlinear analytical model is demonstrated to describe phenomena like kink effect and the multistable-charge-controlled-memory effect (MCCM) in SOI MOSFETs. The calculation of øf,p(t) depends on the device history and generation/recombination rates. Y1 - 1991 U6 - https://doi.org/10.1016/0167-9317(91)90221-X VL - 15 IS - 1-4 SP - 237 EP - 240 ER - TY - CHAP A1 - Yoshioka, Takuya A1 - Sehr, Armin A1 - Delcroix, Marc A1 - Kinoshita, Keisuke A1 - Maas, Roland A1 - Nakatani, Tomohiro A1 - Kellermann, Walter T1 - Survey on approaches to speech recognition in reverberant environments T2 - Asia-Pacific Signal & Information Processing Association annual summit and conference (APSIPA ASC), 2012 : Hollywood, California, USA, 3 - 6 Dec. 2012 N2 - This paper overviews the state of the art in reverberant speech processing from the speech recognition viewpoint. First, it points out that the key to successful reverberant speech recognition is to account for long-term dependencies between reverberant observations obtained from consecutive time frames. Then, a diversity of approaches that exploit the long-term dependencies in various ways is described, ranging from signal and feature dereverberation to acoustic model compensation tailored to reverberation. A framework for classifying those approaches is presented to highlight similarities and differences between them. KW - Speech recognition KW - Hidden Markov models KW - Reverberation KW - Speech KW - Vectors KW - Speech processing Y1 - 2012 SN - 978-0-6157-0050-2 PB - IEEE ER - TY - JOUR A1 - Haumer, Anton A1 - Kral, Christian A1 - Vukovic, Vladimir A1 - David, Alexander A1 - Hettfleisch, Christian A1 - Huzsvar, Attila T1 - A Parametrization Scheme for High Performance Thermal Models of Electric Machines using Modelica JF - IFAC Proceedings Volumes N2 - Thermal models offer great advantages for enhancement of design, protection and control of electric machines. Detailed thermal models take a great number of time constants into account and provide accurate prediction of the temperatures. However, to parameterize such models detailed geometric data are needed. Whenever such detailed information is not available, or the performance of the detailed models is not satisfying, simplified thermal models as described in this paper are advantageous. The calculation of parameters is described in detail, in order to achieve best accordance with temperatures obtained from measurements or from simulations with detailed thermal models. Thermal resistances are calculated from end temperatures of a test run with constant load (and known losses). Thermal capacitances are obtained using optimization to minimize deviation of simulated and measured temperatures during the whole test run. The thermal model of an asynchronous induction machine with squirrel cage is coupled with an electrical model of the drive. For validation, simulation results of an optimally parameterized simplified model are compared with temperatures obtained by simulation of a detailed thermal model, which in turn has been validated against measurement results, both for continuous duty S1 and intermittent duty S6 (6 minutes no-load followed by 4 minutes of 140% nominal load). The deviations are not more than 4 K which is quite satisfying. KW - Electric machines KW - Induction machines KW - Thermal models KW - Model reduction KW - Parameter identification KW - Parameter optimization Y1 - 2012 U6 - https://doi.org/10.3182/20120215-3-AT-3016.00187 SN - 1474-6670 VL - 45 IS - 2 SP - 1058 EP - 1062 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Kral, Christian A1 - Haumer, Anton A1 - Haigis, Matthias A1 - Lang, Hermann A1 - Kapeller, Hansjörg T1 - Comparison of a CFD Analysis and a Thermal Equivalent Circuit Model of a TEFC Induction Machine With Measurements JF - IEEE Transactions on Energy Conversion N2 - For a totally enclosed fan-cooled induction machine, two methods of numerical analysis are compared with measurements. The first numerical method is based on computational fluid dynamics (CFDs) and the second one uses a thermal equivalent circuit (TEC). For the analysis based on CFD, a 3-D induction machine including housing is modeled. The numeric solution of the flow equations is determined for stationary temperature distributions. For the TEC, a discretized one-and-a-half-dimensional model of the induction machine is considered. With the TEC model, stationary and transient operating conditions can be simulated. Measurement results are determined by iron-copper-nickel sensors embedded in the stator winding and the housing, as well as by an IR sensor for measuring the rotor temperature. With these measurement signals, stationary and transient operating conditions can be analyzed. For stationary operating conditions, additionally, the housing temperatures are determined by an IR camera. The investigated simulation and measurement methods reveal different local and global temperatures, and thus, only certain aspects and characteristics of the obtained temperatures can be compared. Nevertheless, certain conclusions can be drawn from comparing these aspects considering the actual restrictions of each of the applied methods. KW - asynchronous machines KW - computational fluid dynamics KW - electric sensing devices KW - Fluid flow KW - induction machines KW - numerical analysis KW - simulation KW - temperature Y1 - 2009 U6 - https://doi.org/10.1109/TEC.2009.2025428 SN - 0885-8969 VL - 24 IS - 4 SP - 809 EP - 818 PB - IEEE ER - TY - JOUR A1 - Kral, Christian A1 - Kapeller, Hansjörg A1 - Gragger, Johannes V. A1 - Haumer, Anton A1 - Kubicek, Bernhard T1 - Phenomenon Rotor Fault-Multiple Electrical Rotor Asymmetries in Induction Machines JF - IEEE Transactions on Power Electronics N2 - In the literature, the effects caused by a single or several adjacently broken rotor bars, or a broken end ring are thoroughly investigated. The phenomenon of various nonadjacently broken rotor bars has not been studied so far in detail. Since nonadjacently broken rotor bars may give rise to fault signatures, which are not directly related with the fault extent, it is important to understand the nature of multiple electrical rotor asymmetries in induction machines. The purpose of this paper is thus to investigate several combinations of electrical rotor asymmetries, to systematically elaborate the phenomena related to the broken bars and end rings. In this paper, a sophisticated simulation model and measurement results are used to analyze the phenomenon rotor fault. KW - asynchronous machines KW - Electrical rotor asymmetries KW - induction machine KW - rotor fault KW - Rotors KW - simulation model KW - skewing Y1 - 2010 U6 - https://doi.org/10.1109/TPEL.2009.2037502 SN - 0885-8993 SN - 1941-0107 VL - 25 IS - 5 SP - 1124 EP - 1134 PB - IEEE ER - TY - CHAP A1 - Ebner, Arno A1 - Haumer, Anton A1 - Simic, Dragan A1 - Pirker, Franz T1 - Interacting Modelica using a Named Pipe for Hardware-in-the-loop Simulation T2 - Modelica 2006, Conference proceedings / 5th International Modelica Conference : September 4 - 5, 2006, Vienna, Austria N2 - The paper presents a concept and an implementation of Modelica simulation interaction using the operating system inter-process communication method of the Named Pipe. The main aim of this presented work is to implement a hardware-in-the-loop simulation (HILS) environment based on Dymola which runs on a normal Microsoft Windows Personal Com-puter. An energy storage test bench is connected by an ana-logue and digital data input/output card with the Dymola simulation computer. With this proposed system, particularly long-time simulations with sample rates up to 30 Hz can be executed very cost effective. Typical applications are simulations of drive cycles to test energy storage systems in electrified vehicles such as batteries or fuel cells. Other application ex-amples are the verification of battery models, thermal management models or battery management sys-tem (BMS) models. In this paper all methods used for implementation are described in detail. Especially the concept of inter-process communication and the concept for real-time and simulation time synchronization is discused. An application example which uses the provided concept is also shown at in this paper. In this example a longitudinal simulation of a vehicle is pre-sented. The startup phase of the internal combusting engine model and a short drive cycle in combination with a connected real battery is shown. Y1 - 2006 UR - https://modelica.org/events/modelica2006/Proceedings/sessions/Session3b1.pdf SP - 261 EP - 266 ER - TY - CHAP A1 - Bäuml, T. A1 - Haumer, Anton A1 - Kapeller, H. A1 - Starzinger, J. A1 - Farzi, P. T1 - Impact of inverter pulse inhibition on the high-voltage supply system of an electric vehicle — A simulative approach T2 - 2011 IEEE Vehicle Power and Propulsion Conference (VPPC 2011) : Powering sustainable transportation ; Chicago, Illinois, USA, 06. - 09.09.2011 N2 - This paper deals with a simulative approach for investigating the impact of inverter pulse inhibition during field weakening operation of permanent magnet synchronous machines and asynchronous induction machines. The modelling and simulation language Modelica is used to design models for the vehicle, the electric machine and the inverter in different abstraction levels. It is shown that when using a permanent magnet synchronous machine, a sudden breakdown of the field weakening current causes induction of high voltages in the stator windings. Hence, the electric system of the vehicle has to be protected against the resulting high currents. Furthermore precautions have to be taken to avoid dangerous driving conditions because of high braking torques in an inverter fault operation mode. In the case of the asynchronous induction machine an inverter pulse inhibition poses no big problem, neither for the electric system of the vehicle, nor the driver. KW - asynchronous machines KW - Connectors KW - electric vehicles KW - Inverters KW - invertors KW - Mathematical model KW - Object oriented modeling KW - permanent magnet machines KW - power engineering computing KW - Rotors KW - synchronous machines KW - Torque KW - Vehicles Y1 - 2011 SN - 978-1-61284-248-6 SN - 978-1-61284-247-9 SN - 978-1-61284-246-2 U6 - https://doi.org/10.1109/VPPC.2011.6043159 SP - 1 EP - 5 PB - IEEE CY - Piscataway, NJ ER - TY - CHAP A1 - Bogomolov, Maxim A1 - Kral, Christian A1 - Haumer, Anton A1 - Lomonova, Elena T1 - Modeling of permanent magnet synchronous machine with fractional slot windings T2 - Proceedings IECON 2012 - 38th Annual Conference on IEEE Industrial Electronics Society ; Ecole de Technologie Superieure de Montreal, Universite du Quebec Montreal, Canada 25 - 28 October, 2012 N2 - This paper focuses on simulation of permanent magnet synchronous machine (PMSM) with fractional-slot windings (FSW) in Modelica. Modeling of the electrical machines with object-oriented approach is shortly described, and a new Modelica library for simulation of electrical machines is introduced. The results of simulation of PMSMs with fractional slot windings are presented and explained. Special attention is paid to the higher harmonics and subharmonics produced by the winding and their influence on machine operation. KW - Concentrated KW - fractional slot KW - harmonics KW - Modelica KW - permanent magnet KW - subharmonics KW - synchronous machines KW - Torque KW - windings Y1 - 2012 SN - 978-1-4673-2421-2 SN - 978-1-4673-2419-9 SN - 978-1-4673-2420-5 U6 - https://doi.org/10.1109/IECON.2012.6388912 SN - 1553-572X SP - 1894 EP - 1899 PB - IEEE CY - Piscataway, NJ ER - TY - CHAP A1 - Hong, Jongman A1 - Hyun, Doosoo A1 - Kang, Tae-june A1 - Lee, Sang Bin A1 - Kral, Christian A1 - Haumer, Anton T1 - Detection and classification of rotor demagnetization and eccentricity faults for PM synchronous motors T2 - 2011 IEEE Energy Conversion Congress and Exposition (ECCE 2011) : Energy conversion innovation for a clean energy future ; Phoenix, Arizona, USA, 17.-22.09.2011 N2 - Condition monitoring of rotor problems such as demagnetization and eccentricity in permanent magnet synchronous motors (PMSM) is essential for guaranteeing high motor performance, efficiency, and reliability. However, there are many limitations to the off-line and on-line methods currently used for PMSM rotor quality assessment. In this paper, an inverter-embedded technique for automated detection and classification of PMSM rotor faults is proposed as an alternative. The main concept is to use the inverter to perform a test whenever the motor is stopped, to detect rotor faults independent of operating conditions or load torque oscillations, which is not possible with motor current signature analysis (MCSA). The d-axis is excited with a dc+ac signal, and the variation in the inductance pattern due to the change in the degree of magnetic saturation caused by demagnetization or eccentricity is observed for fault detection. An experimental study on a 7.5kW PMSM verifies that demagnetization and eccentricity can be detected and classified independent of the load with high sensitivity. KW - AC Machine KW - Condition Monitoring KW - d-axis Inductance KW - Demagnetization KW - Eccentricity KW - fault diagnosis KW - invertors KW - Magnetic Saturation KW - Permanent Magnet (PM) KW - permanent magnet motors KW - Synchronous Motor (SM) KW - synchronous motors Y1 - 2011 SN - 978-1-4577-0542-7 SN - 978-1-4577-0541-0 SN - 978-1-4577-0540-3 U6 - https://doi.org/10.1109/ECCE.2011.6064103 SN - 2329-3721 SN - 2329-3748 SP - 2512 EP - 2519 PB - IEEE CY - Piscataway, NJ ER - TY - CHAP A1 - Hong, Jongman A1 - Lee, Sang Bin A1 - Kral, Christian A1 - Haumer, Anton T1 - Detection of airgap eccentricity for permanent magnet synchronous motors based on the d-axis inductance T2 - 8th IEEE International Symposium on Diagnostics for Electric Machines, Power Electronics & Drives (SDEMPED), 2011 // 05. - 08.09.2011, Bologna, Italy N2 - The majority of the work performed for detecting eccentricity faults for permanent magnet synchronous motors (PMSM) focus on motor current signature analysis (MCSA), as it provides continuous on-line monitoring with existing current sensors. However, MCSA cannot be applied under nonstationary conditions and cannot distinguish faults with load torque oscillations, which are limitations for many PMSM drive applications. In this paper, it is shown that the d-axis inductance, L d , decreases with increase in the severity of eccentricity due to the change in the degree of magnetic saturation, and it is proposed as a new fault indicator. The inverter can be used to perform a standstill test automatically whenever the motor is stopped, to measure L d for eccentricity testing independent of load variations or oscillations, which is not possible with MCSA. An FE and experimental study on a 10hp PMSM verifies that eccentricity can be detected independent of the load with high sensitivity and reliability. KW - Airgap Eccentricity KW - Condition Monitoring KW - Diagnostics KW - fault location KW - inductance KW - load (electric) KW - machine testing KW - Magnetic Saturation KW - Motor Current Signature Analysis (MCSA) KW - permanent magnet motors KW - Permanent Magnet Synchronous Motor KW - synchronous motor protection Y1 - 2011 SN - 978-1-4244-9301-2 SN - 978-1-4244-9303-6 U6 - https://doi.org/10.1109/DEMPED.2011.6063651 SP - 378 EP - 384 PB - IEEE CY - Piscataway, NJ ER - TY - CHAP A1 - Haumer, Anton A1 - Kral, Christian T1 - Modeling a Mains connected PWM Converter with Voltage-Oriented Control T2 - Proceedings of the 8th International Modelica Conference, Technical Univeristy, Dresden, Germany, 20.-22.03.2011 N2 - The majority of industrial controlled induction machine drives are connected to the mains via a diode bridge. However; if reduction of harmonic currents and / or regenerative operation is desired; replacing the diode bridge by an active front-end (AFE) is required. This paper describes two models of an AFE: a power balance model disregarding switching effects; and an ideal switching model of a pulse width modulation (PWM) converter. Both models are controlled utilizing space phasors in a voltage oriented reference frame. Voltage oriented control (VOC) of the mains converter can be compared with field oriented control (FOC) of a machine converter. Design and parametrization of the main parts—synchronization with mains voltage; current controller and DC voltage controller—are described in detail. Additionally; simulation results proving the implementation and demonstrating possible investigations as well as an outlook on further enhancements are presented. KW - Active Front-End KW - PWM Converter KW - Voltage-Oriented Control Y1 - 2011 U6 - https://doi.org/10.3384/ecp11063388 SP - 388 EP - 397 PB - Linköping University Electronic Press ER - TY - CHAP A1 - Jungreuthmayer, C. A1 - Bauml, T. A1 - Winter, O. A1 - Ganchev, M. A1 - Kapeller, H. A1 - Haumer, Anton A1 - Kral, Christian T1 - Heat and fluid flow analysis of an internal permanent magnet synchronous machine by means of computational fluid dynamics T2 - 2011 IEEE International Electric Machines & Drives Conference (IEMDC 2011) ; Niagara Falls, Ontario, Canada, 15 - 18 May 2011 N2 - This paper presents a comprehensive computational fluid (CFD) model of a radial flux permanent magnet synchronous machine with interior magnets. In the CFD model the water jacket cooling and a simplified model of the topology of the distributed stator winding are considered. The heat sources of the CFD model are determined from a finite element analysis of the machine. The numerically determined temperature distributions of the machine are compared with measurement results from sensors located both in the stator and rotor. The particular focus of this paper is the analysis of the temperatures and the heat flow in the air gap and from the stator winding head and the rotor to the inner air. KW - CFD KW - computational fluid dynamics KW - Cooling KW - finite element analysis KW - interior magnet KW - permanent magnet machines KW - permanent magnet synchronous machine KW - Rotors KW - sensor placement KW - stators KW - synchronous machines KW - temperature KW - temperature distribution KW - thermal analysis Y1 - 2011 SN - 978-1-4577-0060-6 SN - 978-1-4577-0061-3 SN - 978-1-4577-0059-0 U6 - https://doi.org/10.1109/IEMDC.2011.5994651 SP - 515 EP - 520 PB - IEEE CY - Piscataway, NJ ER - TY - CHAP A1 - Haumer, Anton A1 - Kral, Christian ED - Otter, Martin ED - Zimmer, Dirk T1 - Motor Management of Permanent Magnet Synchronous Machines T2 - Proceedings of the 9th International MODELICA Conference; September 3-5; 2012; Munich; Germany N2 - Two state-of-the-art machine designs are mainly used in recent electric and hybrid electric vehicles: asynchronous induction machines with squirrel cage which are robust but need a current component to excite the magnetic field; and permanent magnet synchronous machines which rely on somehow more sensible parts but the magnets are able to excite a magnetic field without current. However; if speed gets high enough to reach the field weakening range; for both machine the field oriented control has to prescribe a field current sufficient to reduce the field not to exceed the voltage limits of the stator circuit. Especially for the permanent magnet synchronous machine this paper investigates whether it is possible to determine an optimal field current for every operation point to minimize either total current consumption or losses. KW - Field Oriented Control KW - Optimization of Field Current KW - permanent magnet synchronous machine Y1 - 2012 SN - 978-91-7519-826-2 U6 - https://doi.org/10.3384/ecp12076159 SN - 1650-3686 SN - 1650-3740 SP - 159 EP - 166 PB - Linköping University Electronic Press ER - TY - CHAP A1 - Kapeller, Hansjörg A1 - Haumer, Anton A1 - Kral, Christian A1 - Grabner, Christian ED - Ao, Sio-Iong ED - Gelman, Len T1 - Different Designs of Large Chipper Drives T2 - Electronic Engineering and Computing Technology N2 - This paper presents two simulation models for two variants of a large chipper drive used in a paper mill. If a slip ring induction motor is used, the impact of a rotor circuit rheostat with respect to starting behavior and heavy duty load impulses can be examined. Furthermore a speed controlled squirrel cage induction machine will be investigated. The modeling language for both drives is Modelica. The simulation results for both drives are compared and discussed. KW - induction motor KW - load impulses KW - slip ring KW - speed control KW - squirrel cage Y1 - 2010 SN - 978-90-481-8775-1 SN - 978-90-481-8776-8 U6 - https://doi.org/10.1007/978-90-481-8776-8_9 SP - 93 EP - 104 PB - Springer CY - Dordrecht ER - TY - CHAP A1 - Kral, Christian A1 - Haumer, Anton A1 - Bogomolov, Maxim A1 - Lomonova, Elena T1 - Harmonic wave model of a permanent magnet synchronous machine for modeling partial demagnetization under short circuit conditions T2 - 2012 XXth International Conference on Electrical Machines (ICEM 2012) ; Marseille, France, 2 - 5 September 2012 N2 - This paper proposes a multi domain physical model of permanent magnet synchronous machines, considering electrical, magnetic, thermal and mechanical effects. For each component of the model, the main wave as well as lower and higher harmonic wave components of the magnetic flux and the magnetic potential difference may be considered. The permanent magnets are modeled as discrete azimuthal segments in order to consider possible partial demagnetization effects. For each magnet segment a linearized temperature dependent B-H curve is considered. The main advantage of the presented model is that time transient operational behavior of a permanent magnet synchronous machine can be considered under various electrical, magnetic, thermal and mechanical conditions. The electromagnetic condition of surface magnet machine is compared with finite element analysis. KW - demagnetization KW - harmonic analysis KW - magnetic fields KW - magnetic flux KW - magnetic potential difference KW - permanent magnet synchronous machine KW - reluctance KW - segmentation KW - temperature Y1 - 2012 SN - 978-1-4673-0142-8 U6 - https://doi.org/10.1109/ICElMach.2012.6349880 SP - 295 EP - 301 PB - IEEE CY - Piscataway, NJ ER - TY - CHAP A1 - Kral, Christian A1 - Haumer, Anton A1 - Lee, Sang Bin T1 - Robust thermal model for the estimation of rotor cage and stator winding temperatures of induction machines T2 - 2012 XXth International Conference on Electrical Machines ; Marseille, France, 02.- 05.09.2012 N2 - In this paper a new model for the estimation of the stator winding and rotor cage temperatures of induction machines is presented. This model can be used in series applications of machines operated under dynamic load conditions where stator and rotor temperature shall be monitored. The proposed model relies on a simplified lumped element thermal equivalent circuit model where the stator core temperature serves as input quantity. The great advantage of this model is that it covers ambient and cooling conditions inherently. This leads to great simplicity and robustness. The parametrization and validation of the model through experimental data is presented. Advantages, drawbacks and possible implementations are discussed. KW - asynchronous machines KW - Cooling KW - dynamic load KW - equivalent circuits KW - lumped element thermal equivalent circuit model KW - Rotors KW - squirrel cage induction machine KW - stators KW - temperature estimation Y1 - 2012 SN - 978-1-4673-0142-8 SN - 978-1-4673-0143-5 SN - 978-1-4673-0141-1 U6 - https://doi.org/10.1109/ICElMach.2012.6350127 SP - 1810 EP - 1816 PB - IEEE CY - Piscataway, NJ ER - TY - CHAP A1 - Kral, Christian A1 - Haumer, Anton A1 - Lee, Sang Bin T1 - Innovative thermal model for the estimation of permanent magnet and stator winding temperatures T2 - 2012 IEEE Energy Conversion Congress and Exposition (ECCE 2012) ; Raleigh, NC, USA 15.09.-20.09.2012 N2 - In this paper an innovative thermal model for the determination of the temperatures of the permanent magnets and stator windings is presented. This model relies on one temperature sensor located in the stator core of the machine. The estimated stator winding and permanent magnet temperatures are determined by a simplified thermal lumped element network model with only two time constants. Due to the structure of the model and the measured stator core temperature the proposed thermal model is very robust. Distortion of the cooling circuit are inherently sensed such that the model can be used for the online prediction of temperatures. Experimental results based on an interior permanent magnet synchronous machine are presented to validate the presented model. KW - Cooling KW - dynamic load KW - lumped element thermal equivalent circuit model KW - permanent magnet machines KW - permanent magnet synchronous machine KW - stators KW - synchronous machines KW - temperature estimation KW - temperature sensors KW - variable speed Y1 - 2012 SN - 978-1-4673-0803-8 SN - 978-1-4673-0802-1 SN - 978-1-4673-0801-4 U6 - https://doi.org/10.1109/ECCE.2012.6342386 SN - 2329-3721 SN - 2329-3748 SP - 2704 EP - 2711 PB - IEEE CY - Piscataway, NJ ER - TY - CHAP A1 - Kral, Christian A1 - Haumer, Anton T1 - The New FundamentalWave Library for Modeling Rotating Electrical Three Phase Machines T2 - Proceedings of the 8th International Modelica Conference; March 20th-22nd; Technical Univeristy; Dresden; Germany N2 - This paper introduces the new FundemantalWave library which is included in the Modelica Standard Library 3.2. The presented Modelica package provides models and components of rotating electrical three phase machines. The presented electrical machine models are fully compatible with the original Machines library of the electrical domain but rely on the concept of the magnetic potential and magnetic flux fundamental waves. In this article; the connector concept; the components and electric machine models of the FundemantalWave package will be explained. Additionally; the didactic advantages and the flexibility of the proposed package in with respect to considering more enhanced and sophisticated effects will be discussed. KW - fundamental wave KW - Modelica Standard Library MSL KW - Rotating electrical three phase machines KW - time transients Y1 - 2011 SN - 978-91-7393-096-3 U6 - https://doi.org/10.3384/ecp11063170 SN - 1650-3686 SN - 1650-3740 SP - 170 EP - 179 PB - University Electronic Press CY - Linköping ER - TY - CHAP A1 - Kral, Christian A1 - Haumer, Anton A1 - Grabner, Christian ED - Ao, Sio-Iong ED - Gelman, Len T1 - Determination of Consistent Induction Motor Parameters T2 - Electronic Engineering and Computing Technology N2 - From the rating plate data of an induction motor the nominal efficiency can be determined. Without detailed knowledge of equivalent circuit parameters, partial load behavior cannot be computed. Therefore, a combined calculation and estimation scheme is presented, where the consistent parameters of an equivalent circuit are elaborated, exactly matching the nominal operating point. From these parameters part load efficiencies can be determined. KW - consistent parameters KW - iduction motor KW - partial load efficiency Y1 - 2010 SN - 978-90-481-8775-1 SN - 978-90-481-8776-8 U6 - https://doi.org/10.1007/978-90-481-8776-8_7 VL - 60 SP - 71 EP - 80 PB - Springer CY - Dordrecht ER - TY - CHAP A1 - Kral, Christian A1 - Haumer, Anton A1 - Grabner, Christian ED - Ao, Sio-Iong ED - Gelman, Len T1 - Broken Rotor Bars in Squirrel Cage Induction Machines – Modeling and Simulation T2 - Electronic Engineering and Computing Technology N2 - This paper presents a physical model of a squirrel cage induction machine with rotor topology. The machine is modeled in Modelica, an object oriented multi physical modeling system. The presented machine model is used to investigate electrical rotor asymmetries in induction machines. For the case of a single broken rotor bar a simulation model is compared with measurement results. KW - broken rotor bar KW - induction machines KW - Modelica KW - rotor asymmetries KW - squirrel cage Y1 - 2010 SN - 978-90-481-8775-1 SN - 978-90-481-8776-8 U6 - https://doi.org/10.1007/978-90-481-8776-8_8 SP - 81 EP - 91 PB - Springer CY - Dordrecht ER - TY - CHAP A1 - Kral, Christian A1 - Haumer, Anton ED - Schmidt, Matthias T1 - Object Oriented Modeling of Rotating Electrical Machines T2 - Advances in Computer Science and Engineering Y1 - 2011 SN - 978-953-307-173-2 SN - 978-953-51-5990-2 U6 - https://doi.org/10.5772/15898 SP - 135 EP - 160 PB - IntechOpen ER - TY - JOUR A1 - Snarskii, Andrei A. A1 - Shamonin (Chamonine), Mikhail A1 - Zhenirovskyy, M. I. A1 - Trautner, Ralph T1 - Effect of disorder on the conductivity of two-phase strongly inhomogeneous highly filled composites JF - Theoretical and Mathematical Physics N2 - The effect of the “stir” of a structure (small deviations from strict periodicity) on effective conductivity is considered. For determinate and random deviations, concentration and field dependences of the effective conductivity are found. Numerical experiments with determinate deviations are carried out for the cases of linear (with respect to the field) inclusions embedded in both a linear and nonlinear matrix. The numerical results are compared with the effective conductivity calculated analytically. KW - Small Deviation KW - Numerical Experiment KW - Field Dependence KW - Effective Conductivity KW - Random Deviation Y1 - 2005 U6 - https://doi.org/10.1134/1.1854818 VL - 50 SP - 11 EP - 18 PB - Springer ER - TY - CHAP A1 - Sippenauer, Thomas A1 - Brückl, Oliver A1 - Henneke, Markus T1 - Verankerung von Flexibilität in der Netzplanung T2 - Zukünftige Stromnetze: 27.-28. Januar 2021, 03.-04. Februar 2021 N2 - Die Energiewende führt zu einem steigenden Zubau erneuerbarer Energieerzeugungsanlagen im Verteilungsnetz. Ebenso ist mit einem verstärkten Zuwachs der Elektromobilität zu rechnen, der zu einer weiteren Ausreizung der zulässigen Spannungsbereiche und Leitungsauslastungen beitragen kann. Um die Aufnahmefähigkeit des Verteilungsnetzes zu erhöhen, wurden in der Vergangenheit verschiedene Lösungen entwickelt und etabliert. Ein zusätzlicher Baustein zur Behebung von Netzengpässen und Spannungsproblemen sind zeitliche Verlagerungen von Einspeisungen und Verbrauchslasten in der Mittelspannungsebene. Diese sogenannten Flexibilitätsmaßnahmen sind derzeit noch nicht Stand der Technik. Um einen hohen Nutzen stiften zu können, indem sie zu einer effizienten Einsparung an Asset beitragen, müssen sie in der Netzplanung abbildbar gemacht werden. Dazu sind einerseits geeignete technische und zuverlässigkeitstheoretische Anforderungen an die Flexibilitätsmaßnahmen herauszuarbeiten, um eine möglichst hohe Gesamteffizienz bei Netz- und Anlagenbetreibern zu erzielen und andererseits ein Verfahren zu finden, mit dem Manipulationsmöglichkeiten (INC-DEC-Gaming) ausgeschlossen bzw. geringgehalten werden können. KW - Netzplanung KW - Flexibilität KW - Manipulationsrisiken KW - Feldversuch Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-55632 SN - 978-3-948176-12-9 SP - 79 EP - 92 PB - Conexio GmbH CY - Pforzheim ER - TY - CHAP A1 - Sippenauer, Thomas A1 - Brückl, Oliver T1 - Verankerung von Flexibilität in der Netzplanung T2 - ScienceLab (begleitender Workshop zur Konferenz Zukünftige Stromnetze: 29.-30. Januar 2020, Berlin) N2 - Im Rahmen des Projektes C/sells wurden mehrere Mittelspannungsnetze modelliert, um die aktuellen Spannungsverhältnisse und Leitungsauslastungen nachbilden zu können. Zudem wurden, angelehnt an den Netzentwicklungsplan, Szenarien für den zukünftigen PV-Zubau und die potenzielle Entwicklung der Elektromobilität entworfen. Auf Basis der Ergebnisse lässt sich eine Netzanalyse hinsichtlich Spannungs- und Stromgrenzwertüberschreitungen sowie zu deren potenziellen Auftrittszeitpunkten und Auftrittsdauern durchführen. Parallel wurde anhand von Sensitivitätsanalysen untersucht, welche Wirksamkeit Flexibilitätseinsätze an den verschiedenen Netzknoten auf den Engpass haben. Dadurch kann bestimmt werden, wie effektiv die verfügbaren, in der Regel örtlich gebundenen Flexibilitätsanbieter eingesetzt werden können. Da die Sensitivitäten arbeitspunktabhängig sind, wurden verschiedene Zeitpunkte im Jahresverlauf berechnet und die jeweilige Änderungen der Wirksamkeit ausgewertet. Neben der Höhe der Leistungsabweichung wurde die Flexibilitätsanforderung auch anhand der Einsatzzeitpunkte und Einsatzdauer sowie anhand der Häufigkeit der nötigen Flexibilitätseinsätze charakterisiert. Aus den gewonnenen Erkenntnissen soll abgeleitet werden, inwiefern sich der flexible Einsatz der Verbrauchsanlagen in der Netzplanung verankern lässt. Besonders relevant ist deshalb, mit welcher Verlässlichkeit die Flexibilität abgerufen werden kann. Eine sehr hohe Verlässlichkeit lässt sich je nach Flexibilitätsanbieter möglicherweise nicht oder nur zu sehr hohen Preisen gewährleisten. Die Eignung der Flexibilitätseinsätze wird somit sowohl aus technischer als auch aus wirtschaftlicher Sicht bewertet. Da eine vollständige Verlässlichkeit ohnehin nicht sichergestellt werden kann (technische Störungen einer Anlage, Wettereinflüsse, etc.), werden auch Fallback-Strategien, z. B. Einspeisespitzenkappung, in die Analyse einbezogen. KW - Netzplanung KW - Flexibilität KW - Netzanalyse Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-55592 SN - 978-3-948176-07-5 SP - 77 EP - 81 PB - Conexio GmbH CY - Pforzheim ER - TY - CHAP A1 - Sippenauer, Thomas A1 - Brückl, Oliver T1 - Erschließung der Flexibilitätspotenziale eines Trinkwasserversorgungssystems T2 - ScienceLab (begleitender Workshop zur Konferenz „Zukünftige Stromnetze“: 2020, Berlin) N2 - In Zusammenarbeit mit den Kreiswerken Cham wurde an der OTH Regensburg das Trinkwasserversorgungsgebiet mit allen relevanten Pumpen und Hochbehältern nachgebildet. Mithilfe des Modells kann die aktuelle, füllstandgesteuerte Betriebsweise unter Einhaltung der Randbedingungen (Grenzwerte der Behälterfüllstände, elektrische Verschaltung der Pumpen) simuliert werden. Daraus lässt sich auch das gesicherte, für die Netzplanung geeignete Flexibilitätspotenzial anhand der Leistungsabweichung gegenüber dem regulären Fahrplan, der Einsatzdauer, dem Einsatzzeitpunkt und der Pause zwischen den Flexibilitätsabrufen charakterisieren. In einem Feldversuch wurde vordergründig untersucht, inwiefern der Einsatz von Flexibilität in der Trinkwasserversorgung technisch umsetzbar ist. KW - Netzplanung KW - Flexibilitätspotenzial KW - Trinkwasserversorgung Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-55629 SN - 978-3-948176-07-5 SP - 126 EP - 130 PB - Conexio GmbH CY - Pforzheim ER - TY - JOUR A1 - Brückl, Oliver A1 - Haslbeck, Matthias A1 - Portner, Olaf A1 - Hinz, Gerhard T1 - Kostenminimaler Netzanschluss einer 8-MW-PV-Anlage mithilfe regelbarer Ortsnetztransformatoren JF - Energiewirtschaftliche Tagesfragen N2 - Die steigende Anzahl der Erzeugungsanlagen (EZA) in den Verteilnetzen zwingt viele Verteilnetzbetreiber zum kostenintensiven Netzausbau. Dabei sind die EZA gemäß EEG am technisch und wirtschaftlich günstigsten Verknüpfungspunkt anzuschließen. Zur Bestimmung dieses Punktes ist ein Vergleich sinnvoller Netzanschlussvarianten durchzuführen. Regelbare Ortsnetztransformatoren (RONT) erweitern seit Kurzem die Netzanschlussmöglichkeiten, auch auf Mittelspannungsebene. Das Beispiel eines Anschlusses für eine 8-MW-PV-Anlage zeigt, dass der optimale Netzanschluss eine Kombination zwischen RONT, Spannungsblindleistungsregelung, Trennstellenverlagerung und Leitungsverstärkung sein kann. In diesem Fall bemerkenswert ist, dass der RONT-Einsatz die Netzanschlusskosten um rd. 60 % gegenüber einer separaten Anbindung am Umspannwerk reduziert. Die Autoren beschreiben eingangs die Problematik hoher Netzausbaukosten beim Anschluss von Photovoltaik-Flächenanlagen. Das Vorgehen der durchgeführten Netzanalyse im konkreten Fall (Abb.: Grafische Darstellung des südlichen MS-Netzes der Stadtwerke Kehlheim mit angedeuteter Einspeiseleistung) und die 6 analysierten Netzanschlussvarianten werden beschrieben und diskutiert (Abb.: Gegenüberstellung der Investitionen der verschiedenen Netzausbauszenarien). Die oben genannte günstigste Anschlussvariante besteht aus folgender Kombination: Verlegung der vorhandenen Netztrennstelle zwischen zwei 20-kV-Stränge; Verstärkung einer bestehenden Freileitungsstrecke über 1 km; Einsatz von maximal 15RONT sowie Spannungsblindleistungsregelung durch die PV-Flächenanlage. KW - Blindleistungsregelung KW - elektrische Energieverteilung KW - Investitionskosten KW - Kostenanalyse KW - Mittelspannung (elektrisch) KW - Netzanschluss KW - Netztransformator KW - Ortsnetz (Energie) KW - Photovoltaikanlage KW - Szenarioanalyse KW - Wirtschaftlichkeitsrechnung Y1 - 2014 VL - 64 IS - 6 SP - 63 EP - 65 PB - Energiewirtschaft und Technik, Verl.-Ges. CY - Gräfelfing ER - TY - CHAP A1 - Haslbeck, Matthias A1 - Rauch, Johannes A1 - Brückl, Oliver A1 - Bäsmann, Rainer A1 - Günther, Andreas A1 - Rietsche, Hansjörg A1 - Tempelmeier, Achim T1 - Blindleistungsmanagement in Mittelspannungsnetzen BT - Ergebnisse des Forschungsprojekts SyNErgie T2 - Zukünftige Stromnetze 2019, 30.-31.Jan.2019, Berlin N2 - Die Energiewende führt zu neuen Herausforderungen für Verteilungsnetzbetreiber hinsichtlich der Erbringung von Systemdienstleistungen, der Integrationsfähigkeit weiterer Erzeugungsanlagen und Lasten sowie bei der Gewährleistung einer hohen Versorgungssicherheit. Die Deckung der steigenden Blindleistungsbedarfe seitens der Netzbetriebsmittel, Verbraucher und Erzeuger gewinnt durch den Wegfall der Großkraftwerke für Netzbetreiber zunehmend an Bedeutung.Das abgeschlossene und vom BMWi geförderte Projekt SyNErgie (Laufzeit von 03/2015 bis 05/2018) beschäftigt sich mit der Entwicklung von Blindleistungsmanagementsystemen für Mittelspannungsnetze (MS-Netze). Ziel dabeiist es, das bisher ungenutzte, freie Blindleistungspotenzial betrieblicher Kompensationsanlagen und dezentraler Erzeugungsanlagen (allg.: Q-Quellen) zu nutzen, um die Blindleistungsänderungsfähigkeit 1 eines Verteilungsnetzes zu erhöhen. Diese Veröffentlichung stellt ausgewählte Einzelergebnisse und Erfahrungen des Projektes vor, welche u. a. über zahlreiche Messungen inMS-Netzen bei Firmen mit Anschlusspunkt in der MS-Ebene, Netzsimulationen und mathematische Modelle abgeleitet wurden. Y1 - 2019 UR - https://www.fenes.net/wp-content/uploads/2019/03/SyNErgie_Paper_2019_Kreuzer_Blindleistungsmanagement_MSNetze.pdf SP - 170 EP - 182 ER - TY - GEN A1 - Haslbeck, Matthias A1 - Brückl, Oliver T1 - Liberalisierung von Systemdienstleistungen T2 - Zukünftige Stromnetze für erneuerbare Energien N2 - Die Liberalisierung der Blindleistung und Schaffung von regionalen nicht ausschreibungspflichtigen Q-Beschaffungsprozessen ermöglicht vor allem künftig erhebliche Kostenreduktionspotenziale. Allerdings ist die Etablierung mit umfangreichen Eingriffen in den heutigen Normen- und Gesetzesrahmen verbunden. Damit diese Potenziale gehoben werden können, bedarf es einerseits der Möglichkeit der Kostenanrechnung im Rahmen der Netznutzungsentgelte, andererseits eines Anreizsystems, sinnvoll und sorgsam mit Q umzugehen. Grundsätzlich ist vorher gründlich zu untersuchen, ob und ab welchem Zeitpunkt die Liberalisierung der Blindleistung zielführend ist und wie im Detail die Liberalisierung der Blindleistung auszugestalten wäre. KW - Blindleistung KW - Deregulierung KW - Energiewende KW - Kostenreduktion KW - Netzmanagement KW - Netz-Management KW - Privatisierung KW - Stromerzeugung KW - Stromversorgung KW - Wettbewerb KW - Wiederaufbau KW - Wirkleistung Y1 - 2014 SN - 978-3-943891-34-8 SP - 170 EP - 175 PB - Ostbayerisches Technologie-Transfer-Institut (OTTI) CY - Regensburg ER - TY - CHAP A1 - Kraus, Hermann A1 - Brückl, Oliver T1 - Use and Programmatic Extension of PowerFactory for the Implementation of Automated Network Planning at the Distribution Grid Level T2 - 2020 10th International Conference on Advanced Computer Information Technologies (ACIT): 16-18 Sept. 2020 N2 - In this paper it is presented how the network calculation program PowerFactory is used to implement automated network planning algorithms. PowerFactory’s internal functions and data sets are discussed and it is shown how the functions and data sets have been extended by specially developed scripts to enable the automation of network planning steps. Finally, the methodology applied to calculate grid use cases is briefly discussed. KW - automated grid planning KW - Current measurement KW - distribution grid KW - grid data handling KW - Load flow KW - Load modeling KW - Loading KW - Planning KW - Power cables KW - PowerFactory KW - Reactive power Y1 - 2020 U6 - https://doi.org/10.1109/ACIT49673.2020.9208900 SP - 731 EP - 736 PB - IEEE ER - TY - CHAP A1 - Sterner, Michael A1 - Breuer, Christopher A1 - Drees, Tim A1 - Eckert, Fabian A1 - Maaz, Andreas A1 - Pape, Carsten A1 - Rotering, Niklas A1 - Thema, Martin T1 - Speicherbedarf in der Stromversorgung T2 - Energiespeicher - Bedarf, Technologien, Integration KW - Speicherbedarf KW - Stromversorgung Y1 - 2017 SN - 978-3-662-48893-5 SN - 978-3-662-48892-8 U6 - https://doi.org/10.1007/978-3-662-48893-5_3 SP - 53 EP - 140 PB - Springer Vieweg CY - Berlin ; Heidelberg ET - 2. Auflage ER - TY - CHAP A1 - Rauch, Johannes A1 - Brückl, Oliver A1 - Engel, Bernd ED - Schulz, Detlef T1 - Analysis and optimization of the steady state voltage deviation demand for reactive power planning using installed reactive power sources T2 - NEIS 2022; Conference on Sustainable Energy Supply and Energy Storage Systems, 26-27 September 2022, Hamburg N2 - The provision of reactive power is one option for maintaining the grid voltage, that is defined as an ancillary service in Germany. This paper presents an approach for determining deficient voltage deviation demands within an electrical grid for long term reactive power planning investigations. In contrast to previous approaches, which evaluate the Q-behavior of extended ward elements or grid assets, voltage deviations are analyzed bus-specifically. So further reactive power planning investigations are able to scale and optimize additional reactive power sources directly on planning voltage limits using load flow sensitivity techniques. The focus lies on the analysis of the steady state demand at base case conditions. Therefore, a grid planning process is conceptualized. An optimal power flow algorithm based on Differential Evolution is used for an optimal reactive power dispatch of installed reactive power sources, e. g. reactive power compensation systems or (renewable) energy sources to minimize the total voltage deviation according to voltage limits of Transmission System Operators planning principles. Methodological and processuals specifications as well as an application use case with an exemplary transmission system are presented in this paper. KW - Reactive Power KW - Reactiver Power Planning KW - Voltage Control KW - Optimal Power Flow KW - Differential Evolution Y1 - 2022 UR - https://ieeexplore.ieee.org/document/10048083 SN - 978-3-8007-5983-5 SN - 2510-6902 SP - 175 EP - 182 PB - VDE-Verlag CY - Berlin ER - TY - JOUR A1 - Thema, Martin A1 - Weidlich, Tobias A1 - Hörl, Manuel A1 - Bellack, Annett A1 - Mörs, Friedemann A1 - Hackl, Florian A1 - Kohlmayer, Matthias A1 - Gleich, Jasmin A1 - Stabenau, Carsten A1 - Trabold, Thomas A1 - Neubert, Michael A1 - Ortloff, Felix A1 - Brotsack, Raimund A1 - Schmack, Doris A1 - Huber, Harald A1 - Hafenbradl, Doris A1 - Karl, Jürgen A1 - Sterner, Michael T1 - Biological CO2-Methanation: An Approach to Standardization JF - Energies N2 - Power-to-Methane as one part of Power-to-Gas has been recognized globally as one of the key elements for the transition towards a sustainable energy system. While plants that produce methane catalytically have been in operation for a long time, biological methanation has just reached industrial pilot scale and near-term commercial application. The growing importance of the biological method is reflected by an increasing number of scientific articles describing novel approaches to improve this technology. However, these studies are difficult to compare because they lack a coherent nomenclature. In this article, we present a comprehensive set of parameters allowing the characterization and comparison of various biological methanation processes. To identify relevant parameters needed for a proper description of this technology, we summarized existing literature and defined system boundaries for Power-to-Methane process steps. On this basis, we derive system parameters providing information on the methanation system, its performance, the biology and cost aspects. As a result, three different standards are provided as a blueprint matrix for use in academia and industry applicable to both, biological and catalytic methanation. Hence, this review attempts to set the standards for a comprehensive description of biological and chemical methanation processes. KW - Biological methanation KW - bubble column reactor KW - CO2-methanation KW - CSTR KW - membrane reactor KW - methanation KW - Power-to-Gas KW - Power-to-Methane KW - standardization KW - Trickle-bed reactor Y1 - 2019 U6 - https://doi.org/10.3390/en12091670 N1 - Corresponding author: Martin Thema VL - 12 IS - 9 SP - 1 EP - 32 PB - MDPI ER - TY - CHAP A1 - Sterner, Michael A1 - Eckert, Fabian A1 - Henning, Hans-Martin A1 - Trost, Tobias T1 - Speicherbedarf im Verkehrs- und Chemiesektor T2 - Energiespeicher - Bedarf, Technologien, Integration KW - Speicherbedarf KW - Verkehrssektor KW - Chemische Industrie Y1 - 2017 SN - 978-3-662-48893-5 SN - 978-3-662-48892-8 U6 - https://doi.org/10.1007/978-3-662-48893-5_5 SP - 169 EP - 192 PB - Springer Vieweg CY - Berlin ; Heidelberg ET - 2. Auflage ER - TY - CHAP A1 - Sterner, Michael A1 - Thema, Martin T1 - Vergleich der Speichersysteme T2 - Energiespeicher - Bedarf, Technologien, Integration KW - Energiespeicher Y1 - 2017 SN - 978-3-662-48893-5 SN - 978-3-662-48892-8 U6 - https://doi.org/10.1007/978-3-662-48893-5_12 SP - 645 EP - 682 PB - Springer Vieweg CY - Berlin ; Heidelberg ET - 2. Auflage ER - TY - CHAP A1 - Sterner, Michael A1 - Stadler, Ingo A1 - Eckert, Fabian A1 - Gerhardt, Norman A1 - von Olshausen, Christian A1 - Thema, Martin A1 - Trost, Tobias T1 - Speicherintegration zur Kopplung unterschiedlicher Energiesektoren T2 - Energiespeicher - Bedarf, Technologien, Integration KW - Energieversorgung KW - Energiespeicher KW - Sektorkopplung KW - Systemintegration Y1 - 2017 SN - 978-3-662-48893-5 SN - 978-3-662-48892-8 U6 - https://doi.org/10.1007/978-3-662-48893-5_14 SP - 769 EP - 818 PB - Springer Vieweg CY - Berlin ; Heidelberg ET - 2. Auflage ER - TY - CHAP A1 - Sterner, Michael A1 - Bauer, Franz A1 - Crotogino, Fritz A1 - Eckert, Fabian A1 - von Olshausen, Christian A1 - Teichmann, Daniel A1 - Thema, Martin T1 - Chemische Energiespeicher T2 - Energiespeicher - Bedarf, Technologien, Integration KW - Energiespeicher KW - Elektrochemisches Verfahren KW - Elektrochemische Energieumwandlung Y1 - 2017 SN - 978-3-662-48893-5 SN - 978-3-662-48892-8 U6 - https://doi.org/10.1007/978-3-662-48893-5_8 SP - 327 EP - 493 PB - Springer Vieweg CY - Berlin ; Heidelberg ET - 2. Auflage ER - TY - JOUR A1 - Li, Liwen A1 - Lange, Klaus W. T1 - Planning Principles for Integrating Community Empowerment into Zero-Net Carbon Transformation JF - smart cities N2 - The adoption of the UN 2030 Agenda and the Sustainable Development Goals is a landmark in international sustainability politics. For example, Europe has set ambitious targets to achieve 100 climate-neutral and smart cities by 2030. However, numerous case studies from different countries have found that accelerating the transition to net-zero carbon emissions is easily hampered by the lack of a coherent systems framework, and that implementation gaps remain at the community level. These barriers are often due to a lack of an adequate end-user (i.e., household) input and early planning participation. This work therefore aims to improve on conventional planning methods that do not reflect innovative technologies with uncertainty and may not be applicable due to the lack of community empowerment, which is a dynamic learning and intervention opportunity for end-users at different planning stages (i.e., outreach, survey, planning, implementation, management, and maintenance). Using the lessons learned from participatory action research, whereby the author was involved as a project director throughout the planning and design process, we identified a six-step cycle principle. The steps are (1) collective action commitments, (2) local values and resource identification, (3) carbon footprint inventory, (4) optimized integration of environment, economy, and energy action plans, (5) Flexible strategic energy system plans, and (6) digital performance monitoring. Ultimately, the outcomes provide application support for policymakers and planners and stimulate community engagement to contribute to the achievement of zero net carbon emissions. T2 - Planungsprinzipien für die Integration von Community Empowerment in die Zero-Net Carbon Transformation KW - social science KW - environmental planning KW - responsible research innovation KW - public–private partnerships KW - low-carbon communities KW - participatory action research KW - collective actions Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-57765 VL - 2023 IS - 6 SP - 100 EP - 122 PB - MDPI CY - Basel ER - TY - CHAP A1 - Brückl, Oliver A1 - Krpal, Ondrej A1 - Riepl, Markus T1 - Influence of wind and solar energy on the frequency of switching operations of On-Load Tap-Changers (OLTC) BT - Electric Power Engineering T2 - Proceedings of the 13th International Scientific Conference Electric Power Engineering 2012, EPE 2012; Vol. 2 Y1 - 2012 SP - 719 EP - 722 PB - EPE CY - Brno, Czech Republic ER - TY - CHAP A1 - Monkman, Gareth J. A1 - Böse, Holger A1 - Ermert, Helmut A1 - Klein, Dagmar A1 - Freimuth, Herbert A1 - Baumann, Míchael A1 - Egersdörfer, Stefan A1 - Bruhns, Otto T. A1 - Meier, Alexander A1 - Raja, Kashif ED - Nerlich, Michael ED - Schächinger, Ulrich T1 - Technologies for Haptic Systems in Telemedicine T2 - Integration of Health Telematics into Medical Practice N2 - The ability to image the elastic properties of tissue is potentially useful in a variety of applications. The field of elastic imaging has grown in response to the Potential use of such information in medical diagnosis. Real time ultrasound elastography represents a recent development in determining strain and elasticity distributions. Nevertheless, commonly used imaging techniques rely on the interpretation of two dimensional visual data displayed on a video screen. In reality however, physicians often prefer tactile exploration making the simultaneous portrayal of both video and haptic information most desirable. Since the 1970's many alphanumeric to tactile data conversion methods have been investigated, mainly with the ultimate aim of assisting the blind. More recently, interest has been directed toward the display of pictures on haptically explorable surfaces - Tactile imaging. Such a system would allow surgeons to examine hard sectors contained within soft tissue, and thereby assist in operations held remotely. The expansion of ultrasound elastography to 3D formats would mean the ability to haptically explore regions of the body normally inaccessible to human hands. For three-dimensional imaging the acquisition of sequential tomographic slices using Elastography, combined with image segmentation, enables the reconstruction, quantification and visualisation of tumour volumes. In a collaborative project between four research Institutes, the aim is to produce a prototype three dimensional tactile displays comprising electrically switchable micromachined cells, whose mechanical moduli are governed by phase changes experienced by electrorheological and/or magnetorheological fluids. This will be integrated with a sensory ultrasonic elastography in order to present the human fingers with controllable surfaces capable of emulating biological tissue, muscle and bone. Y1 - 2003 U6 - https://doi.org/10.3233/978-1-60750-941-7-83 SP - 83 EP - 93 PB - IOS Press ER - TY - CHAP A1 - Sterner, Michael A1 - Eckert, Fabian A1 - Gerhardt, Norman A1 - Henning, Hans-Martin A1 - Palzer, Andreas T1 - Speicherbedarf in der Wärmeversorgung T2 - Energiespeicher - Bedarf, Technologien, Integration KW - Energiespeicher KW - Wärmeversorgung Y1 - 2017 SN - 978-3-662-48893-5 SN - 978-3-662-48892-8 U6 - https://doi.org/10.1007/978-3-662-48893-5_4 SP - 141 EP - 168 PB - Springer Vieweg CY - Berlin ; Heidelberg ET - 2. Auflage ER - TY - JOUR A1 - Petchartee, Somrak A1 - Monkman, Gareth J. T1 - Pre-slip sensing using tactile sensor JF - Annals Universitaria Criaiova-Series: Automation, Computers, Electronics and Mechatronics Y1 - 2007 VL - 4 (31) IS - 2 SP - 109 EP - 114 ER - TY - RPRT A1 - Brückl, Oliver T1 - Hemmnisse im Verteilnetzausbau und deren Überwindung N2 - Die Bundesregierung hat ambitionierte Ausbaupfade für die Windenergie und Photovoltaik festgelegt. Allerdings gefährdet vor allem der Verteilnetzausbau und der Netzanschluss der Erneuerbare-Energien-Anlagen (EE-Anlagen) die Erreichung dieser hochgesteckten Ziele. In einem Gutachten im Auftrag der Fraktion von Bündnis 90/DIE GRÜNEN im Bayerischen Landtag identifiziert Prof. Dr.-Ing. Oliver Brückl die wesentlichen Hemmnisse für den beschleunigten Verteilnetzausbau und den Netzanschluss für EE-Anlagen und diskutiert Lösungsansätze in folgenden Bereichen: Regulierungsrahmen für die Verteilnetzbetreiber, Genehmigungsverfahren von Netzausbauprojekten, Praxis der Netzintegration von EE-An lagen, Personalkapazitäten, Beschaffung von Betriebsmitteln und Bau von Anlagen, Zertifizierungsprozess für den Netzanschluss von EE-Anlagen. Im Rahmen des Gutachtens wurden ca. 35 Interviews mit verschiedenen Stakeholdern geführt: Netzbetreiber und Stadtwerke, Projektierer*innen, Herstellerindustrie, Verbände und Behörden. KW - Netzausbau KW - Netzintegration Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-60438 PB - INA – Institut für Netz- und Anwendungstechnik GmbH CY - Waldmünchen ER - TY - JOUR A1 - Brückl, Oliver A1 - Dalisson, Nils A1 - Strohmayer, Bernhard A1 - Haslbeck, Matthias T1 - Spannungshaltungsmaßnahmen im Verteilungsnetz : Systemvergleich JF - EW : Magazin für die Energie-Wirtschaft N2 - Verteilungsnetzbetreibern stehen mittlerweile viele Maßnahmen zur Behebung des Spannungsbandproblems zur Verfügung. Innovative Konzepte wie der regelbare Ortsnetztransformator werden in vielen Pilotprojekten erprobt. Unklar ist jedoch noch, welche Maßnahmen beziehungsweise Kombinationen langfristig wirtschaftlich am günstigsten sind. Die Ostbayerische Technische Hochschule Regensburg untersucht daher in einem Forschungsprojekt verschiedene Maßnahmen, um sie unter wirtschaftlichen, technischen und energetischen Gesichtspunkten bewerten zu können. Der Beitrag untersucht am Beispiel des Netzmodells eines Dorfnetzes mit zahlreichen Photovoltaikanlagen unterschiedliche Szenarien für die Spannungshaltung, wobei u. a. Maßnahmen wie die Parallelverkabelung, das Einspeisemanagement durch Spitzenlastkappung, die Spannungs-Blindleistungsregelung durch die Erzeugungsanlagen sowie ein RONT (regelbarer Ortsnetztransformator) betrachtet werden. Dabei zeigt sich, dass es keine Maßnahme gibt, die in allen Belangen die günstigste Lösung ist. Es zeichnet sich jedoch ab, dass der RONT in vielen Fällen (abhängig vom Durchdringungsgrad) die günstigste oder zumeist eine günstige Lösung zur Erhöhung der Netzanschlusskapazität darstellt. KW - Blindleistungsregelung KW - dezentrale Stromerzeugung KW - Einspeisung KW - Energienetzplanung KW - Netzmodell KW - Netzstabilität (Energienetz) KW - Ortsnetz (Energie) KW - Photovoltaik KW - Regeltransformator KW - Spannungsregelung KW - Vergleichsuntersuchung Y1 - 2014 UR - https://emagazin.ew-magazin.de/de/profiles/a21024e15cd4/editions/fc50e368dae3fad315dd SN - 1619-5795 VL - 113 IS - 6 SP - 66 EP - 69 PB - VWEW-Energieverl. CY - Frankfurt am Main ER - TY - CHAP A1 - Schweiberer, Philipp A1 - Rauch, Johannes A1 - Brückl, Oliver ED - Schulz, Detlef T1 - Long-term analysis of industrial reactive power potentials with consideration of plant-internal grid restrictions using the example of an industrial plant in a distribution grid T2 - NEIS 2022; Conference on Sustainable Energy Supply and Energy Storage Systems, 26-27 September 2022, Hamburg N2 - Since conventional generation plants provide a considerable share of reactive power but are gradually being shut down due to energy transition, leading to power deficits at the transmission grid level, new concepts for the supply of reactive power must be developed. As one possibility for the latter, industrial plants in the distribution grid are considered suitable, as their reactive power potentials can contribute to voltage maintenance and thus to a grid- or system-serving behavior. In this paper, the determination of reactive power potentials provided by industrial compensation systems (ICS) is presented. An industrial plant in the medium voltage grid, with three installed ICSs, is investigated. The potentials are determined and described based on their time characteristics, which provide information about the occurrence and distribution of inductive and capacitive potentials. A grid simulation of the investigated industrial grid is used to analyze the effects of retrieving the reactive power potentials regarding equipment utilizations and voltage limits. KW - Reactive Power KW - Reactive Power Potentials KW - Industrial plant KW - Voltage Stability KW - Long term analysis Y1 - 2022 UR - https://ieeexplore.ieee.org/document/10048065 SN - 978-3-8007-5983-5 SN - 2510-6902 SP - 51 EP - 56 PB - VDE-Verlag CY - Berlin ER - TY - CHAP A1 - Kraus, Hermann A1 - Brückl, Oliver ED - Schulz, Detlef T1 - Concept for the Use of an Automated Network-Planning in the Distribution Grid Level with Coordination of Various Grid Expansion Measures T2 - NEIS 2019 : Conference on Sustainable Energy Supply and Energy Storage Systems, Hamburg 19.09.2019 - 20.09.2019 N2 - In this thesis, a concept for the automated use of network planning processes, which is part of the decision support system developed in the framework of the EU project CrossEnergy, is presented. This publication focuses on the automatic processing of input data and subsequent network modeling as well as the coordination of network extension measures for the systematic solution of static voltage and current problems. Different variants are calculated in order to be able to compare the design technologies. KW - Eingabedaten KW - Entscheidungsunterstützungssystem KW - Konstruktionstechnik KW - Netzausbau KW - Netzmodell KW - Spannung (elektrisch) Y1 - 2019 UR - http://www.vde-verlag.de/proceedings-de/565152022.html SN - 978-3-8007-5152-5 SP - 161 EP - 165 ER - TY - CHAP A1 - Sterner, Michael A1 - Stadler, Ingo T1 - Energiespeicher im Wandel der Zeit T2 - Energiespeicher - Bedarf, Technologien, Integration KW - Energiespeicher Y1 - 2017 SN - 978-3-662-48893-5 SN - 978-3-662-48892-8 U6 - https://doi.org/10.1007/978-3-662-48893-5_1 SP - 3 EP - 24 PB - Springer Vieweg CY - Berlin ; Heidelberg ET - 2. Auflage ER - TY - CHAP A1 - Sterner, Michael A1 - Stadler, Ingo A1 - Eckert, Fabian A1 - Thema, Martin T1 - Speicherintegration in einzelnen Energiesektoren T2 - Energiespeicher - Bedarf, Technologien, Integration KW - Energiespeicher KW - Systemintegration Y1 - 2017 SN - 978-3-662-48893-5 SN - 978-3-662-48892-8 U6 - https://doi.org/10.1007/978-3-662-48893-5_13 SP - 685 EP - 767 PB - Springer Vieweg CY - Berlin ; Heidelberg ET - 2. Auflage ER - TY - GEN A1 - Hipp, Susanne T1 - Designing steerable antenna arrays using simulation T2 - GeMIC 2020 N2 - Antenna arrays are one possibility to design a steerable antenna. Designing an antenna array is a challenging task, where simulation can help to reduce the design complexity. Simulating a complete array can be computational expensive, therefore designing the array is often broken in several task. The first goal is to design and optimize a single antenna element followed by an optimization of this antenna element while considering the vicinity of further equal elements. A unit cell approach is a feasible and easy way to accomplish this task. This approach already considers parameter such as active element pattern and radiation pattern angles. As soon as the unit cell optimization, emulating an infinite array, is finished, the real array with a finite size is simulated, especially considering edge elements and parameters such as excitation patterns or active and passive elements. Due to the high simulation effort at this stage optimization should be kept to a minimum and high performance computing might be required. Finally, a feeding network and different excitations for various beam patterns can be investigated using combined methods to reduce the simulation effort. KW - Antennengruppe KW - Entwurf KW - Simulation Y1 - 2020 ER - TY - CHAP A1 - Sterner, Michael A1 - Bauer, Franz T1 - Definition und Klassifizierung von Energiespeichern T2 - Energiespeicher - Bedarf, Technologien, Integration KW - Energiespeicher Y1 - 2017 SN - 978-3-662-48892-8 U6 - https://doi.org/10.1007/978-3-662-48893-5_2 SP - 25 EP - 49 PB - Springer Vieweg CY - Berlin ; Heidelberg ET - 2. Auflage ER - TY - CHAP A1 - Hopfensperger, Bernhard A1 - Daubner, Andreas A1 - Herrmann, Fabian A1 - Hopkins, Andrew A1 - Mellor, Phil T1 - Investigation of Shifted PWM Methods for a Dual Three-Phase System to Reduce Capacitor RMS Current T2 - PCIM Europe Digital Days 2020: International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management: 07.-08.07.2020, Online [proceedings] N2 - Mild hybrid automotive topologies containing a 48V high power (>15 kW) electric drive system demand a high integration of power electronics and electrical machine. A multi-phase motor winding topology helps to keep the per-phase operating currents to a reasonable level. Close integration and multi-phase system have led to a drive system with dual 3-phase systems supplied by a common 48V DC-link, which allows to shift PWM patterns for reduction of DC-link capacitor ripple current and size. This paper derives some basic rules for combinations of common PWM methods for dual 3-phase systems without magnetic cross-coupling. Experimental measurements verify simulated results. KW - Elektroantrieb KW - dual three phase system Y1 - 2020 UR - https://ieeexplore.ieee.org/document/9177989 SN - 978-3-8007-5245-4 SP - 124 EP - 131 PB - VDE-Verlag CY - Berlin, Offenbach ER - TY - CHAP A1 - Grauvogl, Dominik A1 - Stauder, Peter A1 - Hopfensperger, Bernhard A1 - Gerling, Dieter T1 - Multiphysics Design of a Wound Field Synchronous Machine with Magnetic Asymmetry T2 - Proceedings of the 2021 IEEE International Electric Machines & Drives Conference (IEMDC): 17-20 May 2021, Hartford, CT, USA N2 - In this paper a multiphysics development method is used for designing a novel wound field synchronous machine of the future generation of high voltage traction drives. This method covers the domains of electromagnetics, the mechanical strength, thermal behavior and the magnetic noise. It is shown that the proposed novel asymmetric design with a circular flux barrier in combination with an asymmetric pole offset is fulfilling the requirements according to performance and torque ripple. A fatigue strength rotor mechanic concept is included. A hybrid cooling concept consisting of a water jacket cooled stator and air cooled rotor ensures the needed continuous power. Unacceptable noise levels are excluded by investigating the equivalent radiated power (ERP) level due to radial forces in the air gap. Finally, the multi-physical workflow resulted in a fully developed component with a high degree of maturity. KW - air cooling KW - wound field synchronous machine KW - cooling concept KW - fatigue limit KW - flux barrier Y1 - 2021 U6 - https://doi.org/10.1109/IEMDC47953.2021.9449564 ER - TY - CHAP A1 - Grauvogl, Dominik A1 - Krabinski, Jeffrey A1 - Stauder, Peter A1 - Hopfensperger, Bernhard A1 - Gerling, Dieter T1 - NVH Comparison of a Novel Wound Field Synchronous Machine with Magnetic Asymmetry with a PSM for a HV Electric Drive T2 - 2021 JSAE Annual Congress (Spring) Proceedings; online meeting (No.76-21) N2 - This paper shows how magnetic noises can be reduced with a wound field synchronous machine (WFSM) with magnetic asymmetry compared to a permanent magnet synchronous machine (PSM), operating at base speed range and full load. In order to reproduce a real noise behavior, the two rotor types are operated in a complete electric drive unit (EDU) consisting of an electric motor, gearbox, inverter and overall housing. In the concept study, the noise characteristics of the two electric machines is evaluated and compared via mechanical finite element method (FEM) simulations using the equivalent radiated power (ERP) level and Campbell diagrams. Furthermore, it is shown that critical frequency orders can already be identified by the analysis of the magnetic force density from the electromagnetic design without computationally intensive ERP calculations. In this context, the ERP investigations have shown that the unique feature of the magnetically asymmetric WFSM is the reduction of the slot harmonics. At the current state of the art, the slot harmonics can only be reduced with a rotor skewing. The disadvantage of this is a reduction in performance and a more expensive production. It is also remarkable that the magnetic asymmetry reduces the slot harmonics more than the rotor skewing in the PSM. In addition, both machines are still considered with a short-pitched stator winding to optimize the overall noise level by reducing the 24th frequency order. KW - Elektroantrieb KW - Synchronmaschine KW - traction drive system KW - NVH KW - e-axle KW - magnetic asymmetry Y1 - 2021 UR - https://tech.jsae.or.jp/paperinfo/en/content/p202101.343/ PB - JSAE ER - TY - CHAP A1 - Meister, Johannes A1 - Yeap, Kim Ho A1 - Goh, Magdalene Wan Ching A1 - Nisar, Humaira A1 - Fischer, Johannes A1 - Meier, Hans ED - Nedjah, Nadia ED - Abd El-Latif, Ahmed A. ED - Gupta, Brij B. ED - Mourelle, Luiza M. T1 - The Design of a Pheromone-Based Robotic Varroa Trap for Beekeeping Applications T2 - Robotics and AI for Cybersecurity and Critical Infrastructure in Smart Cities Y1 - 2022 SN - 978-3-030-96736-9 U6 - https://doi.org/10.1007/978-3-030-96737-6_2 SP - 21 EP - 56 PB - Springer International Publishing CY - Cham ER - TY - JOUR A1 - Chen, Rui A1 - Song, Ruizhou A1 - Zhang, Zhuo A1 - Bai, Long A1 - Liu, Fuqiang A1 - Jiang, Pei A1 - Sindersberger, Dirk A1 - Monkman, Gareth J. A1 - Guo, Jianglong T1 - Bio-Inspired Shape-Adaptive Soft Robotic Grippers Augmented with Electroadhesion Functionality JF - Soft Robotics N2 - Soft robotic grippers (SRGs) have been extensively employed in robotic grasping and manipulation applications due to the fact that they are beneficial for pick-and-place of difficult-to-handle and delicate objects with various geometries and stiffness in a comfortable and safer way. This article presents a bio-inspired and shape-adaptive SRG augmented with electroadhesion (EA) functionality, FinEA, by a cost-effective combination of a Fin Ray structured two-fingered SRG with two soft-stretchable EA pads. The EA pads were manufactured by screen printing a layer of electrically conductive and elastomeric carbon black powder mixed with polydimethylsiloxane onto a dielectric substrate. The compliant Fin Ray fingers, composed of soft longitudinal beams and rigid cross beams, were structurally optimized by the finite element method using ABAQUS/CAE based on three key parameters: the open angle of the longitudinal beams, the spacing between the cross beams, and the incline angle of the cross beams. The soft beams were produced by a traditional soft lithography method, whereas the rigid cross beams were three-dimensionally printed. The resultant FinEA grippers were capable of lifting not only flat/thin materials without distorting them due to the employment of EA, but also concave and convex objects due to the passively shape-adaptive Fin Ray structure and the EA functionality. In addition, the proposed FinEA grippers were able to grasp delicate materials and objects whose diameters are larger than the overall gripper length. Furthermore, 65% more weight in shear were picked up by the FinEA gripper when 4 kV was applied compared with 0 V. The FinEA concept provides useful and alternative solution for controllable adhesion-based SRGs and may facilitate the inspiration and development of future SRGs with added functionality and enhanced versatility. KW - electroadhesion KW - Fin Ray structure KW - shape-adaptive KW - soft robotic grippers Y1 - 2019 U6 - https://doi.org/10.1089/soro.2018.0120 VL - 6 IS - 6 SP - 701 EP - 712 PB - Mary Ann Liebert ER - TY - CHAP A1 - Al-Falouji, Ghassan A1 - Prestel, D. A1 - Scharfenberg, Georg A1 - Mandl, Roland A1 - Deinzer, Arnulf A1 - Halang, W. A1 - Margraf-Stiksrud, Jutta A1 - Sick, B. A1 - Deinzer, Renate T1 - SMART-iBrush - Individuelle Unterstützung der Zahnreinigung durch Messung von Bewegung und Druck mit einer intelligenten Zahnbürsten T1 - SMART-iBrush - Individuelle Unterstützung der Zahnreinigung durch Messung von Bewegung und Druck mit einer intelligenten Zahnbürste T2 - Transdisziplinäre Konferenz Technische Unterstützungssysteme, die die Menschen wirklich wollen, 1, 2014, Gießen N2 - Der Forschungsansatz der intelligenten Zahnbürste (SMART-iBrush) verfolgt das Ziel, dass Menschen die für sie effektivste Zahnputzmethode unter individueller Anleitung der Zahnbürste interaktiv trainieren können. Hierzu wurde eine Zahnbürste entwickelt, die Bewegung und Druckverlauf erfasst. Daten werden an ein Smart Device übertragen und können dort in Echtzeit visualisiert werden, z.B. in eher spielerischer Form für Jugendliche oder sachlich nüchterner Form für Erwachsene. In einem Feldversuch wurden Daten von 100-Probanden erfasst. Zukünftig soll mit der SMART-iBrush Technologie, bei deren Entwicklung Wissenschaftler in den Bereichen Psychologie, Zahnmedizin, Embedded Systems und Machine Learning kooperieren, auch die Güte des Putzvorgangs bewertet werden, um die Putzenden aktiv anzuleiten. Intelligent toothbrush research (SMART-iBrush) aims to support humans in learning their individual, most effective tooth brushing technique. Therefore, a toothbrush was developed that measures motion and force applied to its tip. Measurements are transferred to a smart device where they can be visualized in real-time, for example in a more playful fashion for children or a-more factual fashion for adults. Field trials were conducted with 100 participants. Future features of SMART-iBrush 'will include interactive guidance and training techniques. To achieve these goals, researchers from the fields of psychology, dentistry, embedded systems, and machine learning cooperate in SMART-iBrush project. KW - Bewegungsmessung KW - Druckverlauf KW - Embedded-System KW - Erwachsener KW - Feldversuch KW - Jugendlicher KW - Kind KW - maschinelles Lernen KW - Psychologie KW - Zahnbürste KW - Zahnmedizin Y1 - 2014 SN - 978-3-86818-073-2 SP - 315 EP - 327 PB - Helmut-Schmidt-Universität, Universität der Bundeswehr CY - Hamburg ER - TY - JOUR A1 - Kriegl, Raphael A1 - Kravanja, Gaia A1 - Hribar, Luka A1 - Čoga, Lucija A1 - Drevenšek-Olenik, Irena A1 - Jezeršek, Matija A1 - Kalin, Mitjan A1 - Shamonin (Chamonine), Mikhail T1 - Microstructured Magnetoactive Elastomers for Switchable Wettability JF - Polymers N2 - We demonstrate the control of wettability of non-structured and microstructured magnetoactive elastomers (MAEs) by magnetic field. The synthesized composite materials have a concentration of carbonyl iron particles of 75 wt.% (≈27 vol.%) and three different stiffnesses of the elastomer matrix. A new method of fabrication of MAE coatings on plastic substrates is presented, which allows one to enhance the response of the apparent contact angle to the magnetic field by exposing the particle-enriched side of MAEs to water. A magnetic field is not applied during crosslinking. The highest variation of the contact angle from (113 ± 1)° in zero field up to (156 ± 2)° at about 400 mT is achieved in the MAE sample with the softest matrix. Several lamellar and pillared MAE structures are fabricated by laser micromachining. The lateral dimension of surface structures is about 50 µm and the depth varies between 3 µm and 60 µm. A systematic investigation of the effects of parameters of laser processing (laser power and the number of passages of the laser beam) on the wetting behavior of these structures in the absence and presence of a magnetic field is performed. In particular, strong anisotropy of the wetting behavior of lamellar structures is observed. The results are qualitatively discussed in the framework of the Wenzel and Cassie-Baxter models. Finally, directions of further research on magnetically controlled wettability of microstructured MAE surfaces are outlined. The obtained results may be useful for the development of magnetically controlled smart surfaces for droplet-based microfluidics. Y1 - 2022 U6 - https://doi.org/10.3390/polym14183883 N1 - Corresponding authors: Raphael Kriegl und Mikhail Shamonin VL - 14 IS - 18 SP - 1 EP - 21 PB - MDPI ER - TY - GEN A1 - Sindersberger, Dirk A1 - Diermeier, Andreas A1 - Monkman, Gareth J. T1 - Investigation of the electrical properties of magneto-active polymers - Poster T2 - DFG-Tagung, Benedikbeuern, September 2016 Y1 - 2016 ER - TY - CHAP A1 - Diermeier, Andreas A1 - Sindersberger, Dirk A1 - Monkman, Gareth J. T1 - Magneto-Active Polymer Actuator T2 - Actuator 16 : 15th International Conference on New Actuators & 9th International Exhibition on Smart Actuators and Drive Systems : conference proceedings N2 - Magneto-active Polymers (MAP) are closely related to magneto-rheological fluids in that they contain magnetic micro-particles. However, instead of being freely suspended in a carrier fluid they are physically bound within a highly elastic polymer-matrix. The application of an external magnetic field allows changes in the mechanical properties, such as elastic and shear moduli, of the composite material to be achieved. The colossal magneto-rheological effect has been shown to demonstrate changes in Young's modulus by over 1E6 %. Current research concentrates on controllable compliance and the resulting shape memory properties of MAP. This paper deals with recent advancements in this respect, including tubular magneto-active devices with potential applications in medical and other technology. KW - Formgedächtniseffekt KW - Kompositwerkstoff KW - Konzentrat KW - magnetisches Feld KW - magnetorheologische Flüssigkeit KW - Polymer KW - Schermodul Y1 - 2016 SN - 978-3-933339-26-3 SP - 286 EP - 289 PB - WFB CY - Bremen ER - TY - CHAP A1 - Legrand, V. A1 - Böse, Holger A1 - Ermert, Helmut A1 - Freimuth, Herbert A1 - Baumann, Michael A1 - Egersdörfer, Stefan A1 - Meier, Alexander A1 - Dragoi, Daniel T1 - Technologien für haptische Systeme in der Informationsübertragung T2 - IAFW Tagung - Lengenfeld, Mai 2003 Y1 - 2003 ER - TY - JOUR A1 - Jezeršek, Matija A1 - Kriegl, Raphael A1 - Kravanja, Gaia A1 - Hribar, Luka A1 - Drevenšek-Olenik, Irena A1 - Unold, Heiko A1 - Shamonin (Chamonine), Mikhail T1 - Control of Droplet Impact through Magnetic Actuation of Surface Microstructures JF - Advanced Materials Interfaces N2 - An effective method for on-demand control over the impact dynamics of droplets on a magnetoresponsive surface is reported. The surface is comprised of micrometer-sized lamellas from a magnetoactive elastomer on a copper substrate. The surface itself is fabricated using laser micromachining. The orientation of the lamellae is switched from edge-on (orthogonal to the surface) to face-on (parallel to the surface) by changing the direction of a moderate (<250 mT) magnetic field. This simple actuation technique can significantly change the critical velocities of droplet rebound, deposition, and splashing. Rebound and deposition regimes can be switched up to Weber number We < 13 ± 3, while deposition and splashing can be switched in the range of 32 < We < 52. Because a permanent magnet is used, no permanent power supply is required for maintaining the particular regime of droplet impact. The presented technology is highly flexible and enables selective fabrication and actuation of microstructures on complex devices. It has great potential for applications in soft robotics, microfluidics, and advanced thermal management. Y1 - 2023 U6 - https://doi.org/10.1002/admi.202202471 VL - 10 IS - 11 PB - Wiley ER - TY - JOUR A1 - Egersdoerfer, Stefan A1 - Dragoi, Daniel A1 - Monkman, Gareth J. A1 - Füchtmeier, Bernd A1 - Nerlich, M. T1 - Heavy duty robotic precision fracture repositioning JF - Industrial Robot N2 - The application of robotics in manufacturing industry is increasingly spreading to other fields such as service, security and medical, and more recently into orthopedic surgery. Most research projects to date have concentrated on the lighter side of non‐invasive surgery, camera, laser guidance, light cutting and milling through bone. Just as in industrial production and processing applications, the choice of robot and its accompanying control and programming system is absolutely paramount. This simple fact has been justified in recent research dealing with the heavier forms of fracture repositioning robotics in accident surgery. This paper discusses the development of the complete system including robot, end‐effector and sensors. Y1 - 2004 U6 - https://doi.org/10.1108/01439910410566344 SN - 0143-991X VL - 31 IS - 6 SP - 488 EP - 492 PB - Emerald ER - TY - CHAP A1 - Sindersberger, Dirk A1 - Prem, Nina A1 - Monkman, Gareth J. A1 - Zimmermann, Klaus ED - Schlaak, Helmut T1 - Self-Sensing Electroadhesive Polymer Gripper with Magnetically Controllable Surface Geometry T2 - Actuator 2021, International Conference and Exhibition on New Actuator Systems and Applications: GMM conference, February 17-19, 2021, online event N2 - Compared to conventional end effectors, electro-adhesive grippers enable the handling of sensitive, soft or air-permeable materials [1]. The prehension force is based on a strong electric field generated by electrodes resulting in a polarisation of the dielectric and the generation of mirror charges in the workpiece. When the electrode supply voltage is deactivated, the electric field drops,but an electrostatic field remains due to remanent polarisation of the dielectric. The residual charge on the gripper surface reduces only slowly and in combination with other influencing factors can prevent the workpieces from being ejected temporarily or completely. In this work a solution to this problem is presented by means of gripper surface deforming caused by the applicat ion of a magnetic field to a magneto- active polymer (MAP) actuator. The in-creased distance between the workpiece and the dielectric enables precise and controlled ejection. In addition to compliance and deformability, the employment of soft smart materials enables the integration of self-sens-ing mechanisms for the measurement of surface deformation. The embedding of electrically conductive flexible electrodes within the soft silicone dielectric sup port such movements and serves as the n ecessary electrodes for electroadhesion. Since the implementation of the end effectoris based entirely on soft materials, the self-sensing magnetically controllable electroadhesive gripper (SMEG) can be produced in a shape deposition manufacturing (SDM) process [2], [3] and is highly applicable to the field of soft robotics. Y1 - 2021 SN - 9783800754540 U6 - https://doi.org/10.1002/macp.201800222 SP - 318 EP - 320 PB - VDE VERLAG CY - Berlin; Offenbach ER - TY - JOUR A1 - Lang, A. A1 - Monkman, Gareth J. T1 - An analysis of the electrical capacitance between two conducting spheres JF - Journal of Electrostatics N2 - Many modern composites consist of dielectric polymer matrices containing embedded spherical particles. These particles can be electrically conducting and often have magnetic properties. In order to accurately model and simulate such materials, precise calculation of the electrical capacitance between identically sized spheres is required. This is of particular relevance at microscopic dimensions where many smart material-based micro devices are concerned. This may appear trivial for a small number of particles. However, many methods or their analysis appear to be questionable or not applicable at reduced dimensions. In this work, the various methods of analysis are scrutinized before being compared with both simulation and direct measurements. It is surprising to note that of the many works investigated only 3 are in close agreement with both simulation and measurement. Graphical abstract This paper deals with the precise calculation of the electrical capacitance between two conducting spheres of equal, or near equal size.The calculations have been verified by both experimental measurements and simulation. Algorithms in MatLab (Octave) format have been included in the supporting information. KW - Capacitance between spheres KW - Calculation KW - Simulation Experiment Y1 - 2020 U6 - https://doi.org/10.1016/j.elstat.2020.103518 VL - 108 PB - Elsevier ER - TY - JOUR A1 - Chen, Rui A1 - Zhang, Zhuo A1 - Song, Ruizhou A1 - Fang, Cheng A1 - Sindersberger, Dirk A1 - Monkman, Gareth J. A1 - Guo, Jianglong T1 - Time-dependent electroadhesive force degradation JF - Smart Materials and Structures N2 - This paper concerns a comprehensive investigation of time-dependent electroadhesion (EA) force degradation. EA shear force tests on different object materials (a PET, glass, ABS, and wood plate) have shown that force degradation was dominated by residual polarization charges trapped in the EA pad dielectric rather than in the substrate dielectric from which the object to be prehended is made. In order to explain this dynamic physical phenomenon, a model of dielectric polarization and depolarization has been proposed. According to the derived relationship between EA force and discharge time, three different methods intended to mitigate this problem has been compared: (1) the natural discharge method, (2) the high voltage resistor discharge method, and (3) the discharge prior to field polarity reversal method. These methods are useful for generating repeatable and stable EA forces, which are required for the characterization of EA pads and their subsequent employment in material handling, mobile robot crawling and climbing tasks. Y1 - 2020 U6 - https://doi.org/10.1088/1361-665X/ab79b5 VL - 29 IS - 5 PB - IOP Publishing ER - TY - JOUR A1 - Dillinger, Andrea Elisabeth A1 - Mayer, Matthias A1 - Schneider, Magdalena A1 - Weber, Gregor R. A1 - Goeppner, Corinna A1 - Tamm, Ernst R. A1 - Shamonin (Chamonine), Mikhail A1 - Monkman, Gareth J. A1 - Fuchshofer, Rudolf T1 - Reactive changes in optic nerve astrocytes are mediated by CTGF, TGF beta 2 and increasing substratum stiffness JF - Investigative ophthalmology & visual science N2 - Purpose: Patients with primary open-angle glaucoma (POAG) show a stiffer peripapillary sclera, reactive astrocytes and a remodeled lamina cribrosa (LC). The changes are thought to be mediated by TGFβ2 and its downstream mediator CTGF. Recently we developed a murine glaucoma model by overexpressing CTGF in the anterior eye (βb1CTGF). In this study we investigated the glial lamina region of βb1CTGF mice, and the changes of astrocytes in response to CTGF and TGFβ2 as well as increasing substratum stiffness. Methods: Tangential sections of the glial LC of 2-month-old βb1CTGF mice and their wild-type littermates (WT) were stained with phalloidin and antibodies against GFAP, CTGF and fibronectin (FN). Murine optic nerve (ON) astrocytes from CD1 mice were isolated, cultured and characterized by GFAP staining. The astrocytes were treated with TGFβ2 (1ng/ml) and CTGF (50ng/ml and 100ng/ml). In addition, the cells were seeded on PDMS substrata with different stiffness (10, 30 and 60 kPa). Treated cells were analyzed by Western blotting, real-time RT-PCR and immunohistochemistry. Wound healing assays were performed to analyze migration rate following growth factor treatment. Results: βb1CTGF mice showed a massive increase in CTGF and GFAP in the glial LC when compared with WT mice. Moreover, an increase in FN staining and phalloidin-labeled actin was observed in the peripapillary sclera. Murine ON astrocytes reacted on increased substrate stiffness by increasing the synthesis of GFAP, vimentin and CTGF. Treatment of the cells with TGFβ2 and CTGF led to an enhanced migration rate. In addition, treatment resulted in an increased expression and synthesis of ECM proteins, including FN, tropoelastin, collagen type I and III. The in vitro findings correlated with those seen in the glaucoma mouse model. Conclusions: We conclude that changes in the ECM of LC and peripapillary sclera alter their biomechanical properties and thereby induce reactive changes in resident astrocytes. The reactive changes induced by higher stiffness of their surrounding ECM give rise to a self-amplifying process that includes increased TGFβ2/CTGF signaling and leads to synthesis of ECM and cytoskeletal proteins, a process that in turn augments the stiffness at the optic nerve head (ONH). Such a scenario may finally result in a vicious circle as the causative mechanism for ONH deformation in POAG. Y1 - 2015 VL - 56 IS - 7 PB - ASSOC RESEARCH VISION OPHTHALMOLOGY INC ER - TY - JOUR A1 - Sorokin, Vladislav V. A1 - Stepanov, Gennady V. A1 - Shamonin (Chamonine), Mikhail A1 - Monkman, Gareth J. A1 - Khokhlov, Alexei R. A1 - Kramarenko, Elena Yu T1 - Hysteresis of the viscoelastic properties and the normal force in magnetically and mechanically soft magnetoactive elastomers: Effects of filler composition, strain amplitude and magnetic field JF - Polymer N2 - Hysteresis in dynamic modulus, loss factor and normal forces of magnetoactive elastomers (MAEs) comprising various proportions of small (3-5 mu m) and large (50-60 mu m) ferromagnetic particles are experimentally studied using dynamic torsion performed at a fixed oscillation frequency in varying DC magnetic fields. It is shown that hysteresis is a characteristic feature of MAEs observed both under increasing/decreasing magnetic field strength and increasing/decreasing strain amplitude. This hysteresis is attributed to the specific rearrangement of the magnetic filler network under simultaneously applied magnetic field and shear deformation. Rheological properties of the magnetic filler network formed in the magnetic field and, therefore, the rheological properties of MAEs depend strongly on the filler composition and the magnetic field magnitude. Larger magnetic particles and higher magnetic fields provide stronger magnetic networks. Both factors result in the extension of the linear viscoelastic regime to larger strain amplitudes and lead to higher values of shear storage and loss moduli. It is found that the hysteresis width maximises at an intermediate magnetic field where it is attributed to the balance between elastic and magnetic particle interactions. This is apparently where the most significant restructuring of the magnetic network occurs. The hysteresis width decreases with increasing fraction of large particles in the magnetic filler. The loss factor grows significantly when the magnetic network is physically broken by large strains gamma > 1%. A huge (more than one order of magnitude) increase of normal force at maximum magnetic field strengths is observed. It is predicted that any physical quantity depending on the internal structuring of the magnetic filler should demonstrate hysteresis either with a changing magnetic field and constant deformation amplitude or under variable deformation in a constant magnetic field. (C) 2015 Elsevier Ltd. All rights reserved. KW - BEHAVIOR KW - COMPRESSION KW - Dynamic modulus KW - GELS KW - hysteresis KW - Magnetorheological elastomers KW - magnetostriction KW - MODULUS KW - PARTICLES KW - POLYMER COMPOSITES KW - shear Y1 - 2015 U6 - https://doi.org/10.1016/j.polymer.2015.08.040 VL - 76 SP - 191 EP - 202 PB - Elsevier ER - TY - JOUR A1 - Sorokin, Vladislav V. A1 - Ecker, Eva A1 - Stepanov, Gennady V. A1 - Shamonin (Chamonine), Mikhail A1 - Monkman, Gareth J. A1 - Kramarenko, Elena Yu A1 - Khokhlov, Alexei R. T1 - Experimental study of the magnetic field enhanced Payne effect in magnetorheological elastomers JF - Soft Matter N2 - The dynamic modulus and the loss factor of magnetorheological elastomers (MREs) of various compositions and anisotropies are studied by dynamic torsion oscillations performed in the absence and in the presence of an external magnetic field. The emphasis is on the Payne effect, i.e. the dependence of the elastomer magnetorheological characteristics on the strain amplitude and their evolution with cyclically increasing and decreasing strain amplitudes. MREs are based on two silicone matrices differing in storage modulus (soft, G' similar to 10(3) Pa, and hard, G' similar to 10(4) Pa, matrices). For each matrix, the concentration of carbonyl iron particles with diameters of 3-5 mu m was equal to 70 and 82 mass% (22 and 35 vol%, respectively) in the composite material. Samples for each filler content, isotropic and aligned-particles, are investigated. It is found that the Payne effect significantly increases in the presence of an external magnetic field and varies with the cyclical loading which reaches saturation after several cycles. The results are interpreted as the processes of formation-destruction-reformation of the internal filler structure under the simultaneously applied mechanical force and magnetic field. Impacts of matrix elasticity and magnetic interactions on the filler alignment are elucidated. KW - BEHAVIOR KW - CARRAGEENAN KW - DAMPERS KW - MODEL KW - SEALS KW - SENSITIVE ELASTOMERS KW - Shear modulus KW - VISCOELASTIC PROPERTIES KW - WIDE-RANGE MODULATION Y1 - 2014 U6 - https://doi.org/10.1039/c4sm01738b VL - 10 IS - 43 SP - 8765 EP - 8776 PB - ROYAL Society of CHEMISTRY ER - TY - JOUR A1 - Sorokin, Vladislav V. A1 - Stepanov, Gennady V. A1 - Shamonin (Chamonine), Mikhail A1 - Monkman, Gareth J. A1 - Kramarenko, Elena Yu T1 - Magnetorheological behavior of magnetoactive elastomers filled with bimodal iron and magnetite particles JF - Smart materials and structures N2 - Magnetoactive elastomers (MAE) based on soft silicone matrices, filled with various proportions of large diameter ( approximately 50 mu m) iron and small diameter ( approximately 0.5 mu m) magnetite particles are synthesized. Their rheological behavior in homogeneous magnetic fields up to 600 mT is studied in detail. The addition of small magnetite particles facilitates fabrication of uniformly distributed magnetic elastomer composites by preventing aggregation and sedimentation of large particles during curing. It is shown that using the proposed bimodal filler particles it is possible to tailor various magnetorheological (MR) properties which can be useful for different target applications. In particular, either absolute or relative magnetorheological effects can be tuned. The value of the damping factor as well as the range of deformation amplitudes for the linear viscoelastic regime can be chosen. The interdependencies between different MR properties of bimodal MAEs are considered. The results are discussed in the model framework of particle network formation under the simultaneous influence of external magnetic fields and mechanical deformation. KW - damping factor KW - DAMPING PROPERTIES KW - FIELD KW - HYDROGELS KW - MAGNETOELASTIC BEHAVIOR KW - Magnetorheological effect KW - magnetorheological elastomer KW - mechanical hysteresis KW - Payne effect Y1 - 2017 U6 - https://doi.org/10.1088/1361-665X/26/3/035019 VL - 26 IS - 3 PB - IOP Publishing ER - TY - JOUR A1 - Dillinger, Andrea Elisabeth A1 - Weber, Gregor R. A1 - Mayer, Matthias A1 - Schneider, Magdalena A1 - Göppner, Corinna A1 - Ohlmann, Andreas A1 - Shamonin (Chamonine), Mikhail A1 - Monkman, Gareth J. A1 - Fuchshofer, Rudolf A1 - Keller, Kate A1 - Lozano, Diana C. A1 - Clark, Abbot T1 - CCN2/CTGF-A Modulator of the Optic Nerve Head Astrocyte JF - Frontiers in cell and developmental biology (Front Cell Dev Biol.) N2 - In primary open-angle glaucoma (POAG), a neurodegenerative disease of the optic nerve (ON) and leading cause of blindness, the optic nerve head (ONH) undergoes marked structural extracellular matrix (ECM) changes, which contribute to its permanent deformation and to degeneration of ON axons. The remodeling process of the ECM causes changes in the biomechanical properties of the ONH and the peripapillary sclera, which is accompanied by an increased reactivity of the resident astrocytes. The molecular factors involved in the remodeling process belong to the Transforming growth factor (TGF)-β superfamily, especially TGF-β2. In previous publications we showed that TGF-β2 induced ECM alterations are mediated by Cellular Communication Network Factor (CCN)2/Connective Tissue Growth Factor (CTGF) and recently we showed that CCN2/CTGF is expressed by astrocytes of the ON under normal conditions. In this study we wanted to get a better understanding of the function of CCN2/CTGF under normal and pathologic conditions. To this end, we analyzed the glial lamina and peripapillary sclera of CCN2/CTGF overexpressing mice and studied the effect of CCN2/CTGF and increasing substratum stiffness on murine ON astrocytes in vitro. We observed enhanced astrocyte reactivity in the ONH, increased ECM protein synthesis in the peripapillary sclera and increased Ccn2/Ctgf expression in the ONH during the pathologic development in situ. CCN2/CTGF treatment of primary murine ON astrocytes induced a higher migration rate, and increase of ECM proteins including fibronectin, elastin and collagen type III. Furthermore, the astrocytes responded to stiffer substratum with increased glial fibrillary acidic protein, vimentin, actin and CCN2/CTGF synthesis. Finally, we observed the reinforced appearance of CCN2/CTGF in the lamina cribrosa of glaucomatous patients. We conclude that reactive changes in ONH astrocytes, induced by the altered biomechanical characteristics of the region, give rise to a self-amplifying process that includes increased TGF-β2/CCN2/CTGF signaling and leads to the synthesis of ECM molecules and cytoskeleton proteins, a process that in turn augments the stiffness at the ONH. Such a scenario may finally result in a vicious circle in the pathogenesis of POAG. The transgenic CTGF-overexpressing mouse model might be an optimal model to study the chronic pathological POAG changes in the ONH. KW - astrocytes KW - extracellar matrix KW - glaucoma KW - glial lamina KW - growth factors KW - optic nerve KW - stiffness Y1 - 2022 U6 - https://doi.org/10.3389/fcell.2022.864433 VL - 10 PB - frontiers ER - TY - CHAP A1 - Reindl, Andrea A1 - Langer, T. A1 - Meier, Hans A1 - Niemetz, Michael T1 - Comparative Reliability Analysis for Single and Dual CAN (FD) Systems T2 - 27th 2022 International Conference on Applied Electronics (AE): 6-7 September 2022, Pilsen, Czech Republic N2 - Modern cyber-physical systems, such as autonomous vehicles, advanced driver assistance systems, automation systems and battery management systems, result in extended communication requirements regarding the reliability and the availability. The Controller Area Network (CAN) is a broadcast-based protocol which is still used as a standard for serial communication between individual microcontrollers due to its reliability and low power consumption. In addition, it provides mechanisms for detecting transmission errors and retransmitting messages in the event of an error. The enhancement CAN Flexible Data-Rate (CAN FD) offers increased data rates and transmission rates in order to meet the data throughput requirements. In this paper, the mechanisms for reliable data transmission in a CAN FD network are analyzed. To improve reliability, a second identical CAN-FD network is added to the system, using the additional CAN interface already available on common microcontrollers. The redundant communication network is examined in terms of failure rates and the mean time to failure. The reliability over the operation time is calculated for the single and the redundant version of the CAN FD network using the failure rate limits of the ASIL levels. Y1 - 2022 SN - 9781665494816 U6 - https://doi.org/10.1109/AE54730.2022.9920078 SP - 1 EP - 6 PB - IEEE ER - TY - GEN A1 - Reindl, Andrea A1 - Eriksson, Lars A1 - Niemetz, Michael A1 - Sangyoung, Park A1 - Meier, Hans T1 - Control Concepts for a Decentralized Battery Management System Decentralized Battery Management System Global Control Level T2 - 16th International Renewable Energy Storage Conference (IRES2022), 20 to 22 September 2022, Düsseldorf Y1 - 2022 UR - https://www.researchgate.net/publication/363769042_Control_Concepts_for_a_Decentralized_Battery_Management_System_Decentralized_Battery_Management_System_Global_Control_Level PB - Eurosolar ER - TY - GEN A1 - Prem, Nina A1 - Sindersberger, Dirk A1 - Monkman, Gareth J. T1 - Spectroscopic Analysis of Magneto-Active Polymers (MAP) - Poster T2 - DFG-Tagung, Benediktbeuern, September 2017 Y1 - 2017 ER - TY - CHAP A1 - Wetzel, Daniel A1 - Reindl, Andrea A1 - Meier, Hans A1 - Niemetz, Michael A1 - Farmbauer, Michael T1 - A Customized Python Interface for Windows OS for a Low Budget USB-to-CAN-Adapter T2 - International Conference on Electrical, Computer and Energy Technologies (ICECET 2022): 20-22 July 2022, Prague, Czech Republic N2 - Over the last three decades, the Controller Area Network (CAN) has become the dominant communication in embedded systems. Especially for automotive systems it offers advantages including high robustness, low error rate and high reliability combined with low power consumption. Therefore, learning the basics of this bus system is substantial in this field. Nowadays, various media about the functionality and use of CAN exist which make it easy to read into the topic. But often, theory alone is not sufficient. To deepen the understanding, practical implementation contributes significantly. However, affordable and easy-to-use CAN devices for training purposes are scarce. Existing equipment can be divided into expensive professional devices, which have many functions and inexpensive ones for hobbyists, which require difficult configurations. Therefore, a practical solution is a low-budget device equipped with an overlay which deals with the time consuming configurations. This paper covers the development of a python interface for a purchasable cost effective CAN device for Windows OS. The intention is to create an easy-to-use program that enables beginners to get in touch with CAN and collect practical experience. At the start, a brief explanation of the CAN functionality is given. After that, we introduce the hardware used in this project. Next, the software part covers the development of the interface and the integration of this interface into python-can. Furthermore, a virtual playground is introduced for testing purposes. Also, to demonstrate the functionality of the interface, a test program is executed in conjunction with a logic analyzer. KW - Controller area network KW - User Interface KW - USB to CAN KW - Windows KW - python-CAN Y1 - 2022 SN - 978-1-66547-087-2 U6 - https://doi.org/10.1109/ICECET55527.2022.9872574 PB - IEEE CY - Piscataway, NJ, USA ER - TY - CHAP A1 - Körner, Patrick A1 - Reindl, Andrea A1 - Meier, Hans A1 - Niemetz, Michael T1 - A Theoretical Comparison of Different Virtual Synchronous Generator Implementations on Inverters T2 - 2022 24th European Conference on Power Electronics and Applications (EPE'22 ECCE Europe): 05-09 September 2022, Hannover, Germany N2 - The goal to overcome the global climate crisis leads to a rising demand for the usage of Renewable Energy Sources (RES). Decentralized control strategies are needed to allow the integration of RES into the grid. The Virtual Synchronous Generator (VSG) is proposed as a method to add virtual inertia to the grid by emulating the rotating mass of a Synchronous Generator (SG) on the control algorithm of an inverter. This paper presents the VSG control structure as well as the mathematical description in a unified form. Due to the fact that classical droop control can be seen as a special form of the VSG, their correlation is highlighted by evaluating the steady state output characteristics of the inverter. Furthermore, a theoretical comparison between different VSG topologies, including the VISMA-Method 2 and the synchronverter, is given. In order to achieve better voltage stability, principles to add virtual impedance to the inverter's output are described. Y1 - 2022 UR - https://ieeexplore.ieee.org/document/9907497 PB - IEEE ER - TY - THES A1 - Rauch, Johannes T1 - Entwicklung eines Regelverfahrens für einen optimierten und zentralen Blindleistungsabruf zur Beeinflussung des Blindleistungshaushalts von Mittelspannungsnetzen unter Einhaltung von Netzrestriktionen N2 - Die Energiewende führt zu neuen Herausforderungen für Verteilungsnetzbetreiber hinsichtlich der Er-bringung von Systemdienstleistungen, der Integration weiterer Erzeugungsanlagen und Lasten sowie der Gewährleistung einer hohen Versorgungssicherheit und normgerechten Spannungsqualität. Die De-ckung der auftretenden Blindleistungsbedarfe seitens der Netzbetriebsmittel, Verbraucher und Erzeu-gungsanlagen gewinnt durch den Wegfall der Großkraftwerke für Netzbetreiber zunehmend an Bedeu-tung. Das Projekt SyNErgie beschäftigt sich diesbezüglich mit der Entwicklung neuartiger Blindleis-tungsmanagementsysteme für Mittelspannungsnetze. Ziel ist es, das bisher ungenutzte, freie Blindleis-tungspotential betrieblicher Kompensationsanlagen und dezentraler Erzeugungsanlagen (allgemein: Blindleistungsquellen) zu nutzen, um die Blindleistungsänderungsfähigkeit eines Verteilungsnetzes zu erhöhen. Diese Arbeit beschäftigt sich mit der Entwicklung eines zentralen Blindleistungsregelsystems, bei dem Blindleistungsquellen auf Basis von „Optimal Power Flow“-Berechnungen über eine zentrale Recheninstanz angesteuert werden. Zum Einsatz kommt dabei ein Optimierungsalgorithmus, der auf Basis des aktuellen Netzzustandes (Spannungs- und Auslastungsreserven) und des aktuellen Blindleis-tungspotentials der Blindleistungsquellen einen bedarfsoptimalen Abruf koordiniert. Das zentrale Re-gelverfahren wird in Netzmodellen verschiedenartiger Mittelspannungsnetzgruppen und unterschiedli-cher Art und Anzahl von Blindleistungsquellen angewendet sowie im Hinblick auf variierende Zielvor-gaben und Randbedingungen evaluiert und diskutiert. KW - Netzbetriebsführung KW - Blindleistungsmanagement KW - Optimierung Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-6595 ER - TY - THES A1 - Urban, Johannes T1 - Photoelektrisches Direktladen von Elektrofahrzeugen im Inselbetrieb N2 - Die Arbeit befasst sich mit der Ladung von Elektrofahrzeugen durch Solarenergie in einem Inselsystem. Diese Art der Ladung entlastet die Netze und hat einen sehr hohen Leistungswirkungsgrad. Es wurde ein Prototyp einer Direkt-ladestation gebaut, welche verschiedene Elektrofahrzeuge mit einem neuartigen Verfahren aufladen kann. Sie enthält einen optionalen Pufferakkumulator und einen Vollbrücken-Gegentaktwandler für die Ladung bei schlechter Solarleistung. Ein Teil der Arbeit behandelt ausführlich die Auslegung, die Komponenten und bisher undokumentiertes Verhalten von Gegentaktwandlern. Des Weiteren wird das Prinzip der Solardirekt-ladung und deren Umsetzung sowie die Umsetzung des Gesamtsystems beschrieben. Es folgt ein Kapitel zur Wirtschaftlichkeit der Solardirektladung mit Handlungsempfehlungen. Insgesamt lässt sich schließen, dass Solardirektladung bei nutzungsorientierter Auslegung der Anlage und langer Laufzeit wirtschaftlich ist. This work addresses the charging of electric vehicles with solar power in an off-grid system. Charging this way reduces the stress on the grid and has a very high power efficiency. A prototype of a direct charging station was built which is able to charge several different electric vehicles in a novel way. It includes an optional buffer battery and a full bridge converter for being able to charge electric vehicles at times o flow solar power. One chapter explains in detail the design, the components and so far undocumented properties of full and half bridge converters. The principle and the implementation of direct solar charging and the implementation of the whole system is described. The last chapter covers the cost effectiveness of solar chargin gas well as recommendations. All in all it can be stated that solar direct charging is ecomomically advantageous if it is projected according to the user’s demand. KW - Fotovoltaik KW - Stromtankstelle KW - Elektrofahrzeug KW - Pufferspeicher KW - Photovoltaik KW - Ladestation KW - Elektrofahrzeug KW - Pufferspeicher KW - Vollbrückenwandler Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-20285 ER - TY - JOUR A1 - Zimmermann, Klaus A1 - Chavez, Jhohan A1 - Becker, Tatiana I. A1 - Witte, Hartmut A1 - Schilling, Cornelius A1 - Köhring, Sebastian A1 - Böhm, Valter A1 - Monkman, Gareth J. A1 - Prem, Nina A1 - Sindersberger, Dirk A1 - Lutz, I. I. A1 - Merker, L. T1 - An approach to a form-adaptive compliant gripper element based on magneto-sensitive elastomers with a bioinspired sensorized surface JF - Problems of Mechanics Y1 - 2019 SN - 1512-0740 VL - 75 IS - 2 SP - 23 EP - 38 PB - Georgian Technical University CY - Tbilisi ER - TY - JOUR A1 - Prem, Nina A1 - Chavez, Jhohan A1 - Böhm, Valter A1 - Sindersberger, Dirk A1 - Monkman, Gareth J. A1 - Zimmermann, Klaus T1 - Properties of Polydimethylsiloxane and Magnetoactive Polymers with Electroconductive Particles JF - Macromolecular Chemistry and Physics N2 - Magnetoactive polymers are intelligent materials whose mechanical and electrical characteristics are reversibly influenced by external magnetic stimuli. They consist of a highly elastic polymer matrix in which magnetically soft and/or hard particles are distributed by means of special fabrication processes. In addition to ferromagnetic particles such as carbonyl iron powder, electrically conductive particles may also be embedded into the polymer matrix. After characterizing a range of compounds, this work focuses on a comparison of the electrical properties and the suitability of various materials for applications, with particular emphasis on integration into 3D and 6D printing processes. 6D printing is based on the selective positioning of particles in a 3D polymer matrix with a further three degrees of freedom for a graduated dispersion of the particles at certain points and in desired directions. The aim is therefore to ensure that the polymers containing electroconductive tracks have the best possible electrical properties, that is, low resistivity but are still capable of being printed. A comparison between the traditionally used compounds containing graphite and carbon black is made for the first time. This latter is found to be greatly superior both in terms of electrical conductivity and applicability to 3D printing and 6D printing. KW - 3D printing KW - 6D printing KW - carbon black KW - composites KW - electroconductive particles KW - graphite KW - magnetoactive polymers KW - polydimethylsiloxane KW - STRAIN, *MRU Y1 - 2018 U6 - https://doi.org/10.1002/macp.201800222 VL - 219 IS - 18 PB - Wiley ER - TY - JOUR A1 - Kriegl, Raphael A1 - Kovalev, Alexander A1 - Shamonin (Chamonine), Mikhail A1 - Gorb, Stanislav T1 - Tunable contact angle hysteresis on compliant magnetoactive elastomers JF - Extreme Mechanics Letters N2 - It is shown that the advancing (ACA) and receding (RCA) contact angles of water on extremely soft (shear modulus of the order of 10 kPa) magnetoactive elastomer (MAE) films significantly depend on the applied magnetic field. The difference between these angles, known as the contact angle hysteresis, is examined. The roles of the filler concentration and material softness are elaborated. The highest change in the contact angle hysteresis (CAH) from 34° in the absence of magnetic field to 76° in a magnetic field of 0.4 T is achieved for the softest sample with the lowest mass fraction of iron particles (70 wt%). The dependence of the CAH on magnetization history (“magnetic hysteresis”) is observed. This magnetic hysteresis is clearly pronounced for the ACA and has little effect on the RCA. Magnetic field-induced changes of the surface roughness exhibit qualitatively the same hysteresis behavior with regard to the external magnetic field as the ACA. The results are promising for the development of smart surfaces for applications where the dynamic wetting has to be controlled. KW - Magnetoactive elastomers KW - Dynamic wetting KW - Magnetic hysteresis KW - Contact angle hysteresis Y1 - 2023 U6 - https://doi.org/10.1016/j.eml.2023.102049 SN - 2352-4316 VL - 63 PB - Elsevier ER - TY - JOUR A1 - Schächinger, J. A1 - Brückl, Oliver A1 - Becker, Mark A1 - Lechner, Raphael T1 - Results of the Research Project Optibiosy: Biogas plants as stabilizers of the power system? JF - BWK ENERGIE T2 - Biogasanlagen als Stabilisatoren des Stromsystems? Y1 - 2022 SN - 1436-4883 VL - 74 IS - 11-12 SP - 34 EP - 39 PB - VDI-Verlag CY - Düsseldorf ER - TY - RPRT A1 - Klitsman, Maksym A1 - Staudacher, Lars A1 - Brückl, Oliver A1 - Eller, Johannes A1 - Brey, Ludwig A1 - Eigenstetter, Florian T1 - neos - NetzEntwicklungsOffensive Strom - Schlussbericht BT - Projektlaufzeit: 01.09.2017 – 31.12.2021; gefördert durch Bayerisches Staatsministerium für Wirtschaft, Landesentwicklung und Energie N2 - Im Zuge der Energiewende werden die erneuerbaren Energien zur tragenden Säule unserer Stromversorgung. Bis 2025 sollen bundesweit 40-45 % des Stroms aus erneuerbaren Quellen stammen, bis 2050 sogar 80 %. Dabei wird der erzeugte Strom hauptsächlich aus Wind und Sonne stammen. Im Norden der Bundesrepublik wird Wind die Erzeugung dominieren, während im Süden, insbesondere in Bayern der Strom vornehmlich aus Photovoltaik gewonnen werden wird. Um die Ziele der Energiewende zu erreichen, wird neben den ausreichenden Erzeugungskapazitäten auch eine leistungsfähige Infrastruktur zur Verteilung und Nutzung des erneuerbaren Stroms notwendig sein. Planbarkeit und Sicherung der Versorgungsqualität bei zunehmenden Anteilen von volatiler Erzeugung werden dabei zu einer immer größeren Herausforderung. Das Projekt neos hat im engen Verbund mit den beteiligten Partnern wichtige tagesaktuelle Fragestellungen wissenschaftlich erörtert und untersucht, die sich durch die laufende Transformation des Energiesystems und den rasanten Ausbau der Anlagen zur erneuerbaren Energieerzeugung den Projektpartnern stellen. KW - Intelligentes Stromnetz KW - Energiewende KW - Netzplanung KW - Netzausbau KW - Elektromobilität KW - Spannungsqualität KW - regelbarer Ortsnetztransformator KW - Oberschwingungsbelastung KW - Netzberechnung KW - intelligente Netzbetriebsmittel Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-45248 ER - TY - GEN A1 - Füchtmeier, Bernd A1 - Egersdörfer, Stefan A1 - Monkman, Gareth J. A1 - Nerlich, M. T1 - Entwicklung eines Systems zur navigierten und robotergestützten Frakturfixation T2 - Zweite Jahrestagung der Deutschen Gesellschaft für Computer- und Roboterassistierte Chirurgie : 4.-7. November 2003, Nürnberg, Germany; CURAC 2003; Abstract CD-ROM Y1 - 2003 CY - Erlangen-Nürnberg ER - TY - CHAP A1 - Monkman, Gareth J. A1 - Dragoi, Daniel A1 - Egersdörfer, Stefan A1 - Füchtmeier, Bernd A1 - Nerlich, M. T1 - Der Roboter als Hilfsmittel in der Chirurgie // International Mechatronik Forum, Linz, October 2006 T2 - International Mechatronik Forum, Linz Y1 - 2006 ER - TY - GEN A1 - Füchtmeier, Bernd A1 - Nerlich, M. A1 - Monkman, Gareth J. A1 - Egersdörfer, Stefan A1 - Raja, Kashif T1 - Development of a Robotic Navigation and Fracture Fixation System - 7th Intl. Conf. Medical Aspects of Telemedicine, 23 September 2002 T2 - European Journal of Medical Research; Abstracts Y1 - 2002 SN - 2047-783X SP - 28 EP - 29 PB - Biomed Central CY - London ER - TY - CHAP A1 - Forster, Eva A1 - Rabindranath, R. A1 - Mayer, M. A1 - Bentz, Alexander A1 - Böse, Holger A1 - Shamonin (Chamonine), Mikhail A1 - Monkman, Gareth J. T1 - Characterization of ultra soft Magneto-Active Polymers (MAPs) T2 - Conference proceedings / INDUCTICA 2011, Berlin, Germany, 24 - 26 May Y1 - 2011 ER - TY - CHAP A1 - Füchtmeier, Bernd A1 - Egersdörfer, Stefan A1 - Tuma, G. A1 - Monkman, Gareth J. A1 - Nerlich, M. ED - Nerlich, M. ED - Schächinger, U. T1 - Development of a Robotic Navigation and Fracture Fixation System T2 - Integration of Health Telematics into Medical Practice Y1 - 2003 SP - 43 EP - 49 PB - IOS Press ER - TY - CHAP A1 - Haumer, Anton A1 - Kral, Christian T1 - The New EDrives Library: A Modular Tool for Engineering of Electric Drives T2 - Proceedings of the 10th International Modelica Conference, March 10-12, 2014, Lund, Sweden N2 - Simulation is an indispensable tool for the engineering of systems containing electric drives. Depending on the design phase and the engineering task different levels of modeling details are required: proof of concept; investigation of energy and power consumption; design of control; etc. The new EDrives library provides three levels of abstraction for inverters: quasi static (neglecting electrical transients); averaging (neglecting switching effects) and switching – for serving different demands. The inverters can feed the machine models of the Modelica Standard Library: Modelica.Magnetic.FundamentalWave and the new Modelica.Magnetic.QuasiStatic.FundamentalWave. The EDrives library copes with arbitrary phase numbers and can be easily extended to develop new control algorithms. In this publication the structure of the library and the implemented control principles are presented. Furthermore; examples comparing the three different levels of abstraction are included. KW - control KW - Electric machines and drives KW - multi phase KW - power electronics KW - quasi static KW - switching KW - thermal behavior KW - transient Y1 - 2014 SN - 978-91-7519-380-9 U6 - https://doi.org/10.3384/ecp14096155 SN - 1650-3686 SN - 1650-3740 SP - 155 EP - 163 PB - Linköping University Electronic Press ER - TY - CHAP A1 - Dötsch, Horst A1 - Klank, M. A1 - Hagedorn, Oliver A1 - Holthaus, C. A1 - Shamonin (Chamonine), Mikhail A1 - Trifonov, A. T1 - Optimization of Magnetic Garnet Films for Magneto-Optical Imaging of Magnetic Field Distributions T2 - Magneto-Optical Imaging. Proceedings of the NATO Advanced Research Workshop on Magneto-Optical Imaging, Øystese, Norway, 28 - 30 August 2003 N2 - Rare-earth iron garnet films are currently applied for magneto-optical imaging of magnetic field distributions. The physical properties of the films can be controlled by the chemical composition, the growth conditions and the crystallographic orientation. The sensor properties must be optimized according to the application desired. A new optimization method is introduced based on the swing of the photoresponse. An application example is presented. Furthermore, the sensitivity can be strongly enhanced using specific crystallographic orientations which induce an easy plane of magnetization being tilted with respect to the film plane. Experimental results of a [112] oriented garnet film are in good agreement with calculations. The influence of the cubic anisotropy on the sensor performance is discussed. Finally, it is shown that also domain films can be applied for magneto-optical imaging. KW - Magneto-optics KW - imaging KW - magnetic garnet films Y1 - 2004 U6 - https://doi.org/10.1007/978-94-007-1007-8_39 SP - 301 EP - 309 PB - KLuwer CY - Dodrecht ER - TY - JOUR A1 - Gragger, Johannes V. A1 - Haumer, Anton A1 - Einhorn, Markus T1 - Averaged Model of a Buck Converter for Efficiency Analysis JF - Engineering Letters N2 - In this work a buck converter model for multidomain simulations is proposed and compared with a state-of-the-art buck converter model. In the proposed model no switching events are calculated. By avoiding the computation of the switching events in power electronic models the processing time of multidomain simulations can be decreased significantly. The proposed model calculates any operation point of the buck converter in continuous inductor current conduction mode (CICM) while considering the conduction losses and switching losses. It is possible to utilize the proposed modeling approach also for other dc-to-dc converter topologies. Laboratory test results for the validation of the proposed model are included. Y1 - 2010 UR - https://www.researchgate.net/profile/Markus-Einhorn/publication/41668038_Averaged_Model_of_a_Buck_Converter_for_Efficiency_Analysis/links/55100b490cf21287416cb105/Averaged-Model-of-a-Buck-Converter-for-Efficiency-Analysis.pdf VL - 18 CY - Hong Kong ER - TY - THES A1 - Heberl, Michael T1 - Power-to-Ammoniak BT - Möglichkeiten zur erneuerbaren Elektrifizierung und Dekarbonisierung der Ammoniakindustrie N2 - Ammoniak ist Grundbaustein für die Herstellung von Düngemitteln und dementsprechend für die Nahrungsmittelindustrie unentbehrlich. Ca. 40-50 % der Weltbevölkerung sind von Nahrungsmitteln abhängig, die mit Hilfe von Ammoniakdüngern hergestellten wurden. Weltweit wurden alleine im Jahr 2015 181 Mt Ammoniak produziert, wodurch die Ammoniakherstellung mit 1,2 % am gesamten Energieverbrauch der Welt beteiligt ist und für 0,93 % der globalen Treibhausgasemissionen zuständig ist. Auch in Zeiten der Energiewende ist diese Grundstoffchemikalie unentbehrlich, ist aber auf einem anderen Wege herzustellen. Ziel dieser Arbeit ist die Darstellung verschiedener Möglichkeiten zur erneuerbaren Elektrifizierung und Dekarbonisierung der Ammoniakindustrie, wodurch der Einsatz von herkömmlichen Energieträgern wie Erdgas, Kohle und Öl negiert werden kann. Ammoniak wird aktuell über das Haber-Bosch-Verfahren aus den Rohstoffen Erdgas, Kohle und Öl gewonnen. Bei diesem Verfahren wird über einen Primär- und Sekundärreformer Wasserstoff und Stickstoff gewonnen. Andere Gasbestandteile werden gefiltert oder umgewandelt, um schädliche Katalysatorgifte (CO, H2S) zu entfernen. Im Reaktor wird an Eisenkatalysatoren aus Wasserstoff und Stickstoff letztendlich Ammoniak hergestellt. Der Energieverbrauch des Haber-Bosch Verfahrens schwankt zwischen 7,8 MWh/t NH3 für eine moderne und sehr effiziente Anlage mit Erdgas und 13,6 MWh/t NH3 für eine alte mit Kohle betriebene Anlage. An Emissionen treten pro hergestellter Tonne Ammoniak je nach Rohstoff 1,6-3,8 t CO2-eq auf. Neben der Biomassevergasung gibt es mehrere rein elektrische Ansätze zur Ammoniakherstellung. Die unterschiedlichen elektrochemischen Ansätze zur direkten Ammoniaksynthese, wie der Einsatz von Flüssigsalzelektrolyten oder Feststoffelektrolyten, wurden in Abschnitt 3.2 vorgestellt. Einige dieser Technologien zeigen vielversprechende Ansätze, sind jedoch zum aktuellen Zeitpunkt noch zu weit von einem industriellen Einsatz entfernt. Der Einsatz der Wasserelektrolyse in Kombination mit einer Luftzerlegungseinheit ist die derzeit vielversprechendste Methode Ammoniak auf einem strombasierten und dekarbonisierten Wege herzustellen. Bei diesem System wird Wasserstoff im Elektrolyseur und Stickstoff in der Luftzerlegungseinheit hergestellt. Die Ammoniaksynthese findet hierbei in einem Reaktor nach Vorbild des Haber-Bosch-Prozesses statt. Mit diesem System ist ein Energieverbrauch von ca. 10 MWh/t NH3 notwendig. Durch den Einsatz von rein erneuerbar hergestelltem Strom als Energieträger lässt sich mit diesem Technologiezusammenschluss die Ammoniakherstellung komplett Emissionsfrei gestalten. Dadurch können alleine in Deutschland jährlich bis zu 7,8 Mt CO2-eq eingespart werden. Eine zukünftige Umstrukturierung der Ammoniakherstellung und der gesamten chemischen Industrie ist unabdingbar. Diese kann aber nur parallel mit einem Ausbau erneuerbarer Energien umgesetzt werden. Mit der Wasserelektrolyse und der Luftzerlegungseinheit sind die technischen Möglichkeiten für diesen Umbau bereits heute gegeben und brauchen nur noch eingesetzt werden. N2 - Ammonia is a fundamental raw material for the production of fertilizer and essential for the food industry. About 40-50 % of the world population depends on food produced with the assistance of ammonia fertilizers. In 2015 181 Mt ammonia was produced worldwide. The ammonia production is responsible for 1,2 % of the global energy consumption and 0,93 % of the global greenhouse gas emissions. Even in times of the energy transition this base chemical is essential, although it should be produced on a different way. It is therefore the objective of this work to show different possibilities for an electrified and decarbonised ammonia industry powered by renewable energies. As a result the use of conventional energy carriers like gas, coal and oil will be negotiated. Ammonia is produced with the Haber-Bosch process from gas, coal and oil as feedstock. In this process a primary and a secondary reformer is used to produce hydrogen and nitrogen. Other gaseous components are filtered and converted to remove catalyst poisons (CO, H2S). In the reactor iron catalysts are used to produce ammonia out of hydrogen and nitrogen. The energy consumption of the Haber-Bosch process varies between 7,8 MWh/t NH3 for a modern and really efficient gas based plant and 13,6 MWh/t NH3 for an old coal based plant. The production of one ton ammonia causes emissions between 1,6-3,8 t CO2-eq based on the used feedstock. Beside biomass gassing there are several electric technologies to produce ammonia. The different electrochemical technologies to synthesize ammonia on a direct way, like solid state electrolysis or molten salt electrolytes, are shown in section 3.2. Some of these technologies show a good potential, but all of them are far off the use in the industry. The use of an electrolyser in combination with an air separation unit is the most promising way to produce ammonia on an electrified and decarbonised way. In this system hydrogen is produced in the electrolyser and nitrogen in the air separation unit. The ammonia synthesis works in a reactor based on the Haber-Bosch process. Using this system the production of one ton ammonia has an energy consumption of 10 MWh. With the use of renewable energies in this combination of technologies a greenhouse gas emissions free ammonia production is possible. In Germany alone 7,8 t CO2-eq can be saved. A future reorganization of the ammonia industry and the complete chemical industry is indispensable. A parallel expand of renewable energies is necessary to realize this approach. With electrolysers and air separation units the technical possibilities for this reconstruction are already given. All that remains is the implementation of them. KW - Ammoniaksynthese KW - Haber-Bosch KW - Emissionen KW - Erneuerbare Energien Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-22167 ER - TY - JOUR A1 - Gärtner, Sebastian A1 - Marx-Schubach, Thomas A1 - Gaderer, Matthias A1 - Schmitz, Gerhard A1 - Sterner, Michael T1 - Techno-Economic Analysis of Carbon Dioxide Separation for an Innovative Energy Concept towards Low-Emission Glass Melting JF - energies N2 - The currently still high fossil energy demand is forcing the glass industry to search for innovative approaches for the reduction in CO2 emissions and the integration of renewable energy sources. In this paper, a novel power-to-methane concept is presented and discussed for this purpose. A special focus is on methods for the required CO2 capture from typical flue gases in the glass industry, which have hardly been explored to date. To close this research gap, process simulation models are developed to investigate post-combustion CO2 capture by absorption processes, followed by a techno-economic evaluation. Due to reduced flue gas volume, the designed CO2 capture plant is found to be much smaller (40 m3 absorber column volume) than absorption-based CO2 separation processes for power plants (12,560 m3 absorber column volume). As there are many options for waste heat utilization in the glass industry, the waste heat required for CO2 desorption can be generated in a particularly efficient and cost-effective way. The resulting CO2 separation costs range between 41 and 42 EUR/t CO2, depending on waste heat utilization for desorption. These costs are below the values of 50–65 EUR/t CO2 for comparable industrial applications. Despite these promising economic results, there are still some technical restrictions in terms of solvent degradation due to the high oxygen content in flue gas compositions. The results of this study point towards parametric studies for approaching these issues, such as the use of secondary and tertiary amines as solvents, or the optimization of operating conditions such as stripper pressure for further cost reductions potential. KW - economic evaluation KW - CO2-separation KW - glass industry KW - oxyfuel KW - methanation KW - power-to-gas Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-53627 N1 - Corresponding author: Sebastian Gärtner VL - 16 IS - 5 SP - 1 EP - 25 PB - MDPI CY - Basel ER - TY - JOUR A1 - Saveliev, Dmitry V. A1 - Glavan, Gašper A1 - Belan, Viktoria O. A1 - Belyaeva, Inna A. A1 - Fetisov, Leonid Y. A1 - Shamonin (Chamonine), Mikhail T1 - Resonant Magnetoelectric Effect at Low Frequencies in Layered Polymeric Cantilevers Containing a Magnetoactive Elastomer JF - Applied Sciences N2 - In this work, the resonance enhancement of magnetoelectric (ME) coupling at the two lowest bending resonance frequencies was investigated in layered cantilever structures comprising a magnetoactive elastomer (MAE) slab and a commercially available piezoelectric polymer multilayer. A cantilever was fixed at one end in the horizontal plane and the magnetic field was applied horizontally. Five composite structures, each containing an MAE layer of different thicknesses from 0.85 to 4 mm, were fabricated. The fundamental bending resonance frequency in the absence of a magnetic field varied between roughly 23 and 55 Hz. It decreased with the increasing thickness of the MAE layer, which was explained by a simple theory. The largest ME voltage coefficient of about 7.85 V/A was measured in a sample where the thickness of the MAE layer was ≈2 mm. A significant increase in the bending resonance frequencies in the applied DC magnetic field of 240 kA/m up to 200% was observed. The results were compared with alternative designs for layered multiferroic structures. Directions for future research were also discussed. KW - flexible composite KW - low frequency KW - magnetoactive elastomer KW - magnetoelectric effect KW - piezoelectric polymer Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-30637 N1 - corresponding authors: Dmitry V. Saveliev and Mikhail Shamonin VL - 12 IS - 4 SP - 1 EP - 13 PB - MPDI ER - TY - RPRT A1 - Sterner, Michael A1 - Bauer, Franz A1 - Hofrichter, Andreas A1 - Heberl, Michael T1 - Systemanalyse und -integration Power-to-X im Kontext von erneuerbarer Elektrizität als Primärenergie (SPIKE) N2 - Durch das in Paris beschlossene Ziel, die globale mittlere Temperatur auf deutlich unter 2 Grad Celsius gegenüber dem vorindustriellen Niveau zu begrenzen, ist ein Ausstieg aus der Nutzung fossiler Energieträger und Rohstoffe bis zum Jahr 2050 notwendig (WBGU 2016). Daher hat sich die Bundesregierung das Ziel gesetzt, bis zur Mitte des Jahrhunderts eine weitgehende Treibhausgasneutralität zu erreichen. Hierzu ist neben einer Steigerung der Energieeffizienz in allen Sektoren ein Ausbau erneuerbaren Energien notwendig. Dies beinhaltet hauptsächlich den Zubau von Wind‐ und Solarstromanlagen. Somit gewinnt die Sektorkopplung immer mehr an Bedeutung und wird in Zukunft eine tragende Rolle für die Defossilisierung des Energiesystems spielen (BMUB 2016). Als zentrales Element der Sektorkopplung gilt Strom, der über Power‐to‐X (PtX) sowohl energetisch im Wärme‐, und Verkehrssektor als auch stofflich in der Industrie und vor allem im Chemiesektor eingesetzt werden kann (Ausfelder et al. 2018a). Im Rahmen des P2X‐Vorhabens der Kopernikus Forschungsinitiative wird die Sektorkopplung durch die Umwandlung von Strom mittels elektrochemischer Prozesse in stoffliche Ressourcen wie Wasserstoff, Synthesegas oder Kohlenstoffmonoxid untersucht. Der Schwerpunkt liegt auf der Betrachtung der Kopplung von Strom und Verkehr sowie Strom und Chemie und der Untersuchung von Prozessen und Pfaden, die aus ökologischer, ökonomischer und gesellschaftlicher Sicht vorteilhaft sind. Eine vergleichende Einordnung in den Gesamtkontext der Energiewende mit Abwägung zahlreicher Alternativen und Konkurrenztechnologien ist dort allerdings nicht vorgesehen. Zudem werden einige relevante PtX‐Technologien wie Power‐to‐Heat nicht betrachtet. Aus diesem Grund wurden in SPIKE ergänzende PtX‐Technologiepfade aus systemanalytischer Sicht untersucht. Dies sind Power‐to‐Heat (PtH) und Power‐to‐Gas (PtG) über Elektrolyse und optionaler anschließender Methanisierung sowie die Herstellung ausgewählter Pfade der strombasierten Herstellung von Produkten der energieintensiven Industrie. Ziel des Forschungsvorhabens war die Analyse von PtX‐Technologien und Pfaden, deren vergleichende Einordnung im Gesamtkontext der Energiewende sowie die Unterstützung des P2X Roadmapping Prozesses und die Ableitung von Handlungsempfehlungen. Ein besonderer Schwerpunkt lag auf dem Einsatz von PtX im Industriesektor. Für das Vorhaben wurden Arbeitspakete (AP) erstellt, die Untersuchungen zu Technologie, Potenzial, Ökonomie und Ökologie von PtH (AP 1), PtG (AP 2), Power‐to‐Ammoniak, Power‐to‐Ethen und Power‐to‐Propen (AP 3) umfassten. Daraus wurde in AP 4 ein Systemvergleich mit Einordnung von PtX in die Energiewende durchgeführt. Auf dieser Basis und der Identifizierung regulatorischer Rahmenbedingungen für PtX (AP 5) wurde das deutsche Energiesystem samt PtX‐Pfaden in einem Energiesystemmodell abgebildet (AP 6). Die Ergebnisse flossen in das Roadmapping ein (AP 7). Zudem erfolgte ein Austausch mit den Projektpartnern und das Verfassen wissenschaftlicher Abhandlungen (AP 8). KW - Energieintensive Industrie KW - Energiesystemmodellierung KW - Power-to-Gas KW - Power-to-Heat KW - Ökobilanzierung Y1 - 2019 ER - TY - JOUR A1 - Knörzer, S. A1 - Hiller, K-A A1 - Brandt, M. A1 - Niklas, Andreas A1 - Putzger, Jürgen A1 - Monkman, Gareth J. A1 - Danilov, Sergey N. A1 - Ganichev, Sergey D. A1 - Schulz, Irene A1 - Schmalz, Gottfried T1 - Detection of pulsed blood flow through a molar pulp chamber and surrounding tissue in vitro JF - Journal of Clinical Oral Investigations N2 - OBJECTIVES Due to severe limitations of dental pulp sensitivity tests, the direct recording of pulsed blood flow, using photoplethysmography (PPG), has been proposed. In vivo evaluation is methodologically difficult and in vitro models have hitherto been adversely influenced by shortcomings in emulating the in vivo situation. Consequently, the aim of this study was to test an improved data acquisition system and to use this configuration for recording pulsed blood in a new model. MATERIALS AND METHODS We introduced a PPG signal detection system by recording signals under different blood flow conditions at two wavelengths (625 and 940 nm). Pulsed blood flow signals were measured using an in vitro model, containing a molar with a glass pulp and a resin socket, which closely resembled in vivo conditions with regard to volumetric blood flow, pulp anatomy, and surrounding tissue. RESULTS The detection system showed improved signal strength without stronger blanketing of noise. On the tooth surface, it was possible to detect signals emanating from pulsed blood flow from the glass pulp and from surrounding tissue at 625 nm. At 940 nm, pulp derived signals were recorded, without interference signals from surrounding tissue. CONCLUSION The PPG-based method has the potential to detect pulsed blood flow in small volumes in the pulp and (at 625 nm) also in adjacent tissues. CLINICAL RELEVANCE The results show the need for clear differentiation of the spatial origins of blood flow signals of any vitality test method to be applied to teeth. KW - Dental Pulp KW - Dental Pulp Cavity KW - Dental Pulp Test KW - Laser-Doppler Flowmetry KW - Molar Y1 - 2019 U6 - https://doi.org/10.1007/s00784-018-2530-y VL - 23 IS - 3 SP - 1121 EP - 1132 PB - Springer Nature ER - TY - JOUR A1 - Glavan, Gašper A1 - Kettl, Wolfgang A1 - Brunhuber, Alexander A1 - Shamonin (Chamonine), Mikhail A1 - Drevenšek-Olenik, Irena T1 - Effect of Material Composition on Tunable Surface Roughness of Magnetoactive Elastomers JF - Polymers N2 - We investigated magnetic-field-induced modifications of the surface roughness of magnetoactive elastomers (MAEs) with four material compositions incorporating two concentrations of ferromagnetic microparticles (70 wt% and 80 wt%) and exhibiting two shear storage moduli of the resulting composite material (about 10 kPa and 30 kPa). The analysis was primarily based on spread optical reflection measurements. The surfaces of all four materials were found to be very smooth in the absence of magnetic field (RMS roughness below 50 nm). A maximal field-induced roughness modification (approximately 1 m/T) was observed for the softer material with the lower filler concentration, and a minimal modification (less than 50 nm/T) was observed for the harder material with the higher filler concentration. All four materials showed a significant decrease in the total optical reflectivity with an increasing magnetic field as well. This effect is attributed to the existence of a distinct surface layer that is depleted of microparticles in the absence of a magnetic field but becomes filled with particles in the presence of the field. We analyzed the temporal response of the reflective properties to the switching on and off of the magnetic field and found switching-on response times of around 0.1 s and switching-off response times in the range of 0.3-0.6 s. These observations provide new insight into the magnetic-field-induced surface restructuring of MAEs and may be useful for the development of magnetically reconfigurable elastomeric optical surfaces. KW - magnetically tunable surface reflectivity KW - magnetically tunable surface roughness KW - magnetorheological elastomer KW - magnetorheological polymers KW - surface properties Y1 - 2019 U6 - https://doi.org/10.3390/polym11040594 N1 - Corresponding author: Gašper Glavan VL - 11 IS - 4 SP - 1 EP - 13 PB - MDPI CY - Basel ER - TY - RPRT A1 - Thema, Martin A1 - Kaul, Anja A1 - Sterner, Michael A1 - Heberl, Michael T1 - Optimierung eines Rieselbett-Bioreaktors für die dynamische mikrobielle Biosynthese von Methan mit Archaeen-Mikroorganismen in Power-to-Gas-Anlagen N2 - Das übergeordnete Ziel des Vorhabens war die Entwicklung neuer technologischer Möglichkeiten für den biologischen Methanisierungsprozess mit Archaeen1 in Power-to-Gas-Anwendungen. Im Gegensatz zur technisch ausgereiften chemisch-katalytischen Methanisierung sind hier noch Potenziale zur Optimierung verfahrenstechnischer und biologischer Prozesse für das Speicherkonzept Power-to-Gas [7] vorhanden. Dabei sollte zum einen ein Rieselbett-Bioreaktor optimiert, simuliert und für die Hochskalierung vorbereitet werden. Zum anderen sollte eine Kombination optimal geeigneter Mikroorganismen und Packungsmaterialien selektiert und deren Verhalten und Eignung im Reaktor analysiert werden. Das Verhalten des entwickelten Systems sollte zunächst im Labor- und Technikumsmaßstab und anschließend im Feldtest an einer bestehenden Power-to-Gas-Anlage untersucht werden. Hauptziel während des Feldtests war die Produktion von einspeisefähigem Methan sowie dessen Einspeisung ins Gasnetz. Ein Hauptziel des Projektes war es, die Normung und Standardisierung notwendiger Systemparameter und Semantik zur Beschreibung und Einbindung biologischer Methanisierungseinheiten in Power-to-Gas-Anlagen voranzutreiben. Dies sollte zum einen die Vergleichbarkeit der wissenschaftlichen Erkenntnisse verbessern und zum anderen unterstützend bei der Kommerzialisierung der Technologie wirken. Aus dem Projekt heraus wurde so die neue Normungsreihe VDI 4635 Power-to-X beim Verein Deutscher Ingenieure angestoßen. KW - Biologische Methanisierung KW - Power-to-Gas KW - Erneuerbare Energien KW - Rieselbett-Bioreaktor KW - Archaeen Y1 - 2021 U6 - https://doi.org/10.2314/KXP:1815321555 ER - TY - JOUR A1 - Glavan, Gašper A1 - Salamon, Peter A1 - Belyaeva, Inna A. A1 - Shamonin (Chamonine), Mikhail A1 - Drevensek-Olenik, Irena T1 - Tunable surface roughness and wettability of a soft magnetoactive elastomer JF - Journal of applied polymer science N2 - Surface topographical modifications of a soft magnetoactive elastomer (MAE) in response to variable applied magnetic field are investigated. The analysis is performed in situ and is based on optical microscopy, spread optical reflection and optical profilometry measurements. Optical profilometry analysis shows that the responsivity of magnetic field-induced surface roughness with respect to external magnetic field is in the range of 1 mu m/T. A significant hysteresis of surface modifications takes place for increasing and decreasing fields. Investigations of shape of sessile water droplets deposited on the MAE surface reveal that field-induced topographical modifications affect the contact angle of water at the surface. This effect is reversible and the responsivity to magnetic field is in the range of 20 degrees/T. Despite the increased surface roughness, the apparent contact angle decreases with increasing field, which is attributed to the field-induced protrusion of hydrophilic microparticles from the surface layer. KW - CONTACT KW - EVAPORATION KW - FORCE KW - hydrophobic polymers KW - MAGNETIC-MATERIALS KW - magnetism and magnetic properties KW - optical properties KW - STIMULI-RESPONSIVE SURFACES KW - stimuli-sensitive polymers KW - structure-property relationships Y1 - 2018 U6 - https://doi.org/10.1002/app.46221 VL - 135 IS - 18 PB - Wiley ER - TY - CHAP A1 - Niklas, Andreas A1 - Hiller, Karl-Anton A1 - Jäger, Andreas A1 - Brandt, M. A1 - Putzger, Jürgen A1 - Ermer, C. A1 - Schulz, Irene A1 - Monkman, Gareth J. A1 - Giglberger, Stephan A1 - Hirmer, Marion A1 - Danilov, Sergey N. A1 - Ganichev, Sergey D. A1 - Schmalz, Gottfried ED - Arenholt-Bindslev, Dorthe ED - Schmalz, Gottfried T1 - In vitro optical detection of simulated blood pulse in a human tooth pulp model T2 - Biocompatibility of Dental Materials Y1 - 2013 PB - Springer CY - Berlin ; Heidelberg ER - TY - CHAP A1 - Klitsman, Maksym A1 - Brückl, Oliver A1 - Eller, Johannes ED - Schulz, Detlef T1 - Analysis and simulation of the population driving behaviour and charging processes at different charging station types with electric vehicles T2 - NEIS 2021, Conference on Sustainable Energy Supply and Energy Storage Systems: 13-14. September 2021, Hamburg N2 - Electric vehicles are one of the important components of the energy transition, which is necessary for the CO2 emission reduction. In order to estimate the influence of electromobility on electric grids at present day and in the future, the generation of realistic charge profiles is necessary. The main objective of this study is the development of an algorithm, which generates realistic charge time series of electric vehicles. The very huge and detailed input surveys enable to define different population groups, representing specific driving behaviour. These groups are then composed and scaled up, according to the statistical population structure of a chosen town or city in Germany, and show typical driving behaviour of all inhabitants. The charge profiles are calculated for several charge station types, based on daily electric vehicle user mobility, day type and household type. In addition, charge process occurrence is evaluated through a model, involving charge infrastructure presence, attractiveness of corresponding charge station type and charge process necessity. Y1 - 2021 SN - 978-3-8007-5651-3 SP - 254 EP - 260 PB - VDE-Verlag ER - TY - JOUR A1 - Sydoruk, O. A1 - Shamonin (Chamonine), Mikhail A1 - Radkovskaya, A. A1 - Zhuromskyy, O. A1 - Shamonina, Ekaterina A1 - Trautner, Ralph A1 - Stevens, C. J. A1 - Faulkner, Grahame A1 - Edwards, David J. A1 - Solymar, L. T1 - Mechanism of subwavelength imaging with bilayered magnetic metamaterials: Theory and experiment JF - Journal of Applied Physics N2 - We present a theoretical and experimental study of a bilayered metamaterial structure for subwavelength imaging of magnetic field. The simplest version of such a structure consists of one or two linear arrays of capacitively loaded split pipe resonators. Its subwavelength physics is governed by strongly anisotropic magnetic coupling between individual resonators and by propagation of magnetoinductive waves with wavelength much shorter than the wavelength of the electromagnetic radiation in free space. It is shown that magnetoinductive waves propagating in the lateral direction are undesirable because they spread the image. Good subwavelength imaging is achieved when, due to the strong interlayer coupling, a stop band in the vicinity of the resonant frequency appears in the dispersion characteristics. The imaging properties of the single and double lens are compared and it is shown that the double lens has a superior performance. Excellent agreement is obtained between experimental and theoretical results for the magnetic field in the image plane in the operation frequency range of 30–60 MHz. It is shown that the same mechanism is responsible for image formation using bilayered planar metamaterial structures and a design of such a lens comprising two planar layers with a total of 542 elements is provided. The conclusions are not restricted to the radio frequency region because the elements can be scaled down. Y1 - 2007 U6 - https://doi.org/10.1063/1.2714782 VL - 101 IS - 7 PB - AIP ER - TY - JOUR A1 - Radkovskaya, A. A1 - Sydoruk, O. A1 - Shamonin (Chamonine), Mikhail A1 - Shamonina, Ekaterina A1 - Stevens, C. J. A1 - Faulkner, Grahame A1 - Edwards, David J. A1 - Solymar, L. T1 - Experimental study of a bi-periodic magnetoinductive waveguide: comparison with theory JF - IET Microwaves, Antennas & Propagation N2 - Magnetoinductive waves propagating along a line consisting of two kinds of metamaterial elements are studied. Both elements are made up by the same metallic loop but are loaded by different capacitors resulting in different resonant frequencies. The dispersion characteristics are derived from phase and amplitude measurements for the cases when the line consists of (i) identical elements and (ii) of alternating elements. Both planar (elements in the same plane as the axis of the line) and axial (elements perpendicular to the axis of the line) configurations are investigated. It is shown that in the bi-periodic arrangement of the elements, the dispersion curves have a forward wave in the lower frequency branch and a backward wave in the upper frequency branch independent of the configuration whether it is planar or axial. Comparisons between theoretical and experimental results show good agreement. KW - magnetic materials KW - metamaterials KW - wave propagation KW - dispersion (wave) KW - waveguides Y1 - 2007 U6 - https://doi.org/10.1049/iet-map:20050289 SN - 1751-8733 VL - 1 IS - 1 SP - 80 EP - 83 PB - IET ER - TY - JOUR A1 - Radkovskaya, A. A1 - Sydoruk, O. A1 - Shamonin (Chamonine), Mikhail A1 - Stevens, C. J. A1 - Faulkner, Grahame A1 - Edwards, David J. A1 - Shamonina, Ekaterina A1 - Solymar, L. T1 - Transmission properties of two shifted magnetoinductive waveguides JF - Microwave and Optical Technology Letters N2 - Transmission properties of magnetoinductive waves propagating in two coupled one-dimensional metamaterial arrays are studied both experimentally and theoretically for the case when one of the arrays is shifted relative to the other one. Two different kinds of resonant metamaterial elements, split-pipe and spiral resonators, are investigated in the frequency bands centred at 46.2 and 586 MHz, respectively. It is shown that within a certain frequency range close to the resonant frequencies the transmission is strongly dependent on the shift. Theoretical calculations based on the impedance matrix show good agreement with the experimental results Y1 - 2007 U6 - https://doi.org/10.1002/mop.22344 VL - 49 IS - 5 SP - 997 EP - 1230 PB - Wiley ER - TY - CHAP A1 - Mayer, M. A1 - Forster, Eva A1 - Rabindranath, R. A1 - Bentz, Alexander A1 - Böse, Holger A1 - Shamonin (Chamonine), Mikhail A1 - Monkman, Gareth J. T1 - Highly compliant Magneto-Active Polymers (MAPs) T2 - Actuator'11, Bremen, May 2011 Y1 - 2011 ER - TY - CHAP A1 - Nerlich, M. A1 - Monkman, Gareth J. A1 - Füchtmeier, Bernd A1 - Egersdörfer, Stefan T1 - Development of a Robotic Navigation and Fracture Fixation System T2 - 1. Jahrestagung der Deutschen Gesellschaft für Computer- und Roboterassistierte Chirurgie (CURAC), Leipzig, 2002 Y1 - 2002 ER - TY - JOUR A1 - Hörner, Eduard A1 - Krykanov, Ivan M. A1 - Chashin, Dmitry V. A1 - Fetisov, Yury K. A1 - Fetisov, Leonid Y. A1 - Shamonin (Chamonine), Mikhail T1 - Magnetoelectric characteristics of cobalt-iron alloy–lead zirconate titanate bilayer planar structures JF - International Journal of Materials Research N2 - The characteristics of both direct and converse magnetoelectric (ME) interactions in bilayer composite structures comprising layers of a commercially available magnetostrictive permendur CoFe alloy and different piezoelectric PZT ceramics are investigated in detail by the method of harmonic field modulation. It is shown that, given the optimum DC magnetic bias field, a high piezomagnetic coefficient in the alloy leads to increased efficiency of ME interactions. The resonant behavior of frequency dependencies of the magnetoelectric voltage is explained by excitation of bending and planar mechanical oscillations in the structures. The results are of interest for developing highly sensitive AC magnetic field sensors and magnetoelectric transducers for energy harvesting from mechanical vibrations. KW - Composite materials KW - Magnetostriction KW - Piezoelectricity KW - Magnetically ordered materials KW - Magnetoelectric effect Y1 - 2012 U6 - https://doi.org/10.3139/146.110776 VL - 103 IS - 11 PB - De Gruyter ER - TY - JOUR A1 - Saveliev, Dmitry V. A1 - Fetisov, Leonid Y. A1 - Chashin, Dmitri V. A1 - Shabin, P. A. A1 - Vyunik, D. A. A1 - Fedulov, Feodor A1 - Kettl, W. A1 - Shamonin (Chamonine), Mikhail T1 - Method of Measuring Deformations of Magnetoactive Elastomers under the Action of Magnetic Fields JF - Russian Technological Journal Y1 - 2019 U6 - https://doi.org/10.32362/2500-316x-2019-7-4-81-91 VL - 7 IS - 4 SP - 81 EP - 91 ER - TY - CHAP A1 - Holthaus, C. A1 - Hagedorn, Oliver A1 - Klank, M. A1 - Shamonin (Chamonine), Mikhail A1 - Trifonov, A. A1 - Dötsch, Horst T1 - Preparation and Characterization of Sensitive Magnetic Garnet Films for MOI Applications T2 - Magneto-Optical Imaging. Proceedings of the NATO Advanced Research Workshop on Magneto-Optical Imaging, Øystese, Norway, 28 - 30 August 2003 N2 - Magnetic garnet films prepared by liquid phase epitaxy on paramagnetic substrates of gadolinium gallium garnet are currently used for the imaging of magnetic field distributions. This application is based on the Faraday rotation which can be strongly enhanced by bismuth incorporation. For gray scale imaging the plane of the sensor film should be an easy plane of magnetization so that no domains nucleate. However, incorporation of bismuth induces a strong positive uniaxial anisotropy perpendicular to the film plane, especially if films of [111] orientation are used. To counteract this unwanted behavior neodymium and/or praseodymium are substituted in addition to bismuth. These two elements cause a very strong negative anisotropy. This is tested experimentally by growing series of garnet films with gradually changing composition and growth parameters. KW - Magneto-optics KW - Imaging KW - Garnet films Y1 - 2004 U6 - https://doi.org/10.1007/978-94-007-1007-8_42 SP - 329 EP - 336 PB - Kluwer CY - Dodrecht ER - TY - CHAP A1 - Gärtner, Sebastian A1 - Rank, Daniel A1 - Heberl, Michael A1 - Gaderer, Matthias A1 - Sterner, Michael T1 - Integration of Power-To-Methane into Glass Melting Processes T2 - Proceedings of the International Renewable Energy Storage Conference (IRES 2022) N2 - The glass industry is facing increased challenges regarding climate protection targets and rising energy costs. The integration of renewable energy including conversion and storage is a key for both challenges in this energy-intensive industrial sector, which has been mainly relying on fossil gas so far. The options considered to this point for reducing CO2 emissions and switching to a renewable energy supply involve far-reaching changes of the established melting processes. This entails significant risks in terms of influences on glass quality and stable production volumes. The presented approach for the integration of a Power-to-Methane (PtM) system into the glass industry is a completely new concept and has not been considered in detail before. It allows the use of established oxyfuel melting processes, the integration of fluctuating renewable energy sources and a simultaneous reduction of CO2 emissions by more than 78%. At the same time, natural gas purchases become obsolete. A techno-economic evaluation of the complete PtM process shows, that 1,76 €/m3 or 1,26 €/kg synthetic natural gas are possible with renewable energy supply. Using electricity from the energy grid would require electricity prices < 0,126 €/kWh to allow cost competitive PtM processes in the glass industry. Such electricity prices could be achieved by electricity market-based optimization and operation of the PtM system. This operation strategy would require AI-based algorithms predicting availabilities and prices on future-based markets. KW - Power-to-Gas KW - Methanation KW - Glass Melting KW - Glass Industry KW - Decarbonisation Y1 - 2023 U6 - https://doi.org/10.2991/978-94-6463-156-2_12 SN - 2589-4943 VL - 16 SP - 147 EP - 161 PB - Atlantis Press ER - TY - JOUR A1 - Klank, M. A1 - Hagedorn, Oliver A1 - Shamonin (Chamonine), Mikhail A1 - Rosen, H. A1 - Dötsch, Horst T1 - Sensitive magneto-optical sensors for visualization of magnetic fields using garnet films of specific orientations JF - Journal of Applied Physics N2 - Garnet films of high Faraday rotation are applied as magneto-optical sensors to visualize the spatial distribution of magnetic fields. Using specific orientations, the induced anisotropy can generate an easy plane of magnetization which is inclined with respect to the film plane. If the magnetization lies in this plane a very high sensitivity can be achieved. The dependence of the geometrical orientation of the easy plane on the growth direction is calculated and the sensitivity and dynamic range are derived. Experimental results of a [112] oriented garnet film are in good agreement with calculations. Y1 - 2002 U6 - https://doi.org/10.1063/1.1516839 VL - 92 PB - AIP ER - TY - JOUR A1 - Glavan, Gašper A1 - Belyaeva, Inna A. A1 - Ruwisch, Kevin A1 - Wollschlaeger, Joachim A1 - Shamonin (Chamonine), Mikhail T1 - Magnetoelectric Response of Laminated Cantilevers Comprising a Magnetoactive Elastomer and a Piezoelectric Polymer, in Pulsed Uniform Magnetic Fields JF - Sensors N2 - The voltage response to pulsed uniform magnetic fields and the accompanying bending deformations of laminated cantilever structures are investigated experimentally in detail. The structures comprise a magnetoactive elastomer (MAE) slab and a commercially available piezoelectric polymer multilayer. The magnetic field is applied vertically and the laminated structures are customarily fixed in the horizontal plane or, alternatively, slightly tilted upwards or downwards. Six different MAE compositions incorporating three concentrations of carbonyl iron particles (70 wt%, 75 wt% and 80 wt%) and two elastomer matrices of different stiffness are used. The dependences of the generated voltage and the cantilever's deflection on the composition of the MAE layer and its thickness are obtained. The appearance of the voltage between the electrodes of a piezoelectric material upon application of a magnetic field is considered as a manifestation of the direct magnetoelectric (ME) effect in a composite laminated structure. The ME voltage response increases with the increasing total quantity of the soft-magnetic filler in the MAE layer. The relationship between the generated voltage and the cantilever's deflection is established. The highest observed peak voltage around 5.5 V is about 8.5-fold higher than previously reported values. The quasi-static ME voltage coefficient for this type of ME heterostructures is about 50 V/A in the magnetic field of approximate to 100 kA/m, obtained for the first time. The results could be useful for the development of magnetic field sensors and energy harvesting devices relying on these novel polymer composites. KW - cantilever KW - composites KW - DEMAGNETIZING FACTORS KW - direct magnetoelectric effect KW - laminated structure KW - magnetic field sensor KW - magnetoactive elastomer KW - piezoelectric polymer Y1 - 2021 U6 - https://doi.org/10.3390/s21196390 N1 - Corresponding authors: Gašper Glavan, Mikhail Shamonin VL - 21 IS - 19 SP - 1 EP - 19 PB - MDPI CY - Basel ER - TY - GEN A1 - Hirmer, Marion A1 - Danilov, Sergey N. A1 - Giglberger, Stephan A1 - Putzger, Jürgen A1 - Niklas, Andreas A1 - Jäger, Andreas A1 - Hiller, Karl-Anton A1 - Schmalz, Gottfried A1 - Redlich, B. A1 - Monkman, Gareth J. A1 - Ganichev, Sergey D. T1 - Spectroscopic Study of Human Teeth and Blood from Visible to Terahertz Frequencies for Clinical Diagnosis of Dental Pulp Vitality T2 - PACS, November 11, 2011 N2 - Transmission spectra of wet human teeth and dentin slices, together with blood of different flow rates were investigated. The measurements carried out over a wide spectral range, from visible light down to terahertz radiation. The results make it possible to find the optimum light frequency for an all-optical determination of pulpal blood flow and, consequently, for clinically diagnosis of tooth vitality. Y1 - 2011 ER - TY - JOUR A1 - Kral, Christian A1 - Haumer, Anton A1 - Grabner, Christian T1 - Consistent Induction Motor Parameters for the Calculation of Partial Load Efficiencies by Means of an Advanced Simulation Model JF - Engineering Letters N2 - From the rating plate data of an induction motor the nominal efficiency can be determined. Without detailed knowledge of equivalent circuit parameters, partial load behavior cannot be computed. Therefore, a combined calculation and estimation scheme is presented, where the consistent parameters of an equivalent circuit are elaborated, exactly matching the nominal operating point. From these parameters part load efficiencies can be determined. KW - Induction motor KW - consistent parameters KW - partial load efficiency Y1 - 2010 SN - 1816-0948 SN - 1816-093X VL - 18 IS - 1 CY - Hong Kong ER - TY - JOUR A1 - Glavan, Gašper A1 - Belyaeva, Inna A. A1 - Shamonin (Chamonine), Mikhail T1 - Multiferroic Cantilevers Containing a Magnetoactive Elastomer: Magnetoelectric Response to Low-Frequency Magnetic Fields of Triangular and Sinusoidal Waveform JF - Sensors N2 - In this work, multiferroic cantilevers comprise a layer of a magnetoactive elastomer (MAE) and a commercially available piezoelectric polymer-based vibration sensor. The structures are fixed at one end in the horizontal plane and the magnetic field is applied vertically. First, the magnetoelectric (ME) response to uniform, triangle-wave magnetic fields with five different slew rates is investigated experimentally. Time and field dependences of the generated voltage, electric charge, and observed mechanical deflection are obtained and compared for four different thicknesses of the MAE layer. The ME responses to triangular and sinusoidal wave excitations are examined in contrast. Second, the ME response at low frequencies (≤3 Hz) is studied by the standard method of harmonic magnetic field modulation. The highest ME coupling coefficient is observed in the bias magnetic field strength of ≈73 kA/m and it is estimated to be about 3.3 ns/m (ME voltage coefficient ≈ 25 V/A) at theoretically vanishing modulation frequency (f→0 Hz). Presented results demonstrate that the investigated heterostructures are promising for applications as magnetic-field sensors and energy harvesting devices. KW - magnetoactive elastomer KW - piezoelectric polymer KW - multilayer cantilever KW - direct magnetoelectric effect KW - magnetic field sensing Y1 - 2022 U6 - https://doi.org/10.3390/s22103791 N1 - Corresponding authors: Gašper Glavan und Mikhail Shamonin VL - 22 IS - 10 SP - 1 EP - 17 PB - MDPI CY - Basel ER - TY - GEN A1 - Pershina, K. V. A1 - Saveliev, Dmitry V. A1 - Glavan, Gašper A1 - Chashin, Dmitri V. A1 - Belyaeva, Inna A. A1 - Fetisov, Leonid Y. A1 - Shamonin (Chamonine), Mikhail T1 - The voltage response of a structure comprising a magnetoactive-elastomer cylinder and a piezoelectric material to magnetic field step excitations T2 - The 4th International Baltic Conference on Magnetism (IBCM 2021) : Svetlogorsk, Russia August 29 - September 2, 2021 : Book of Abstracts Y1 - 2021 UR - http://smba.science/wp-content/uploads/2021/10/IBCM-2021-Book-of-Abstracts-5.pdf SP - 182 PB - Immanuel Kant Baltic Federal University, Kaliningrad, Russia ER - TY - RPRT A1 - Rank, Daniel A1 - Heberl, Michael A1 - Sterner, Michael T1 - Die CO2-Bilanz der OTH [Ostbayerischen Technische Hochschule Regenburg] BT - Tool für Hochschulen und Firmen Y1 - 2020 UR - https://sae58cb7e2208a3d2.jimcontent.com/download/version/1613400473/module/9240277976/name/1. Sitzung AG_Präsentation Prof. Sterner-1.pdf ER - TY - GEN A1 - Sterner, Michael A1 - Heberl, Michael T1 - The ORBIT-Project: Biological methanation in a trickle-bed reactor - key results and next steps T2 - 5th Nuremberg Workshop on Methanation and 2nd Generation, Nürnberg Friedrich-Alexander-Universität, 28.05.2021 KW - biologische Methanisierung KW - Archaeen KW - Power-to-Gas KW - Erneuerbare Energien KW - Rieselbett Bioreaktor Y1 - 2021 ER - TY - JOUR A1 - Lovšin, Matija A1 - Brandl, Dominik A1 - Glavan, Gašper A1 - Belyaeva, Inna A. A1 - Cmok, Luka A1 - Coga, Lucija A1 - Kalin, Mitjan A1 - Shamonin (Chamonine), Mikhail A1 - Drevenšek-Olenik, Irena T1 - Reconfigurable Surface Micropatterns Based on the Magnetic Field-Induced Shape Memory Effect in Magnetoactive Elastomers JF - Polymers N2 - A surface relief grating with a period of 30 mu m is embossed onto the surface of magnetoactive elastomer (MAE) samples in the presence of a moderate magnetic field of about 180 mT. The grating, which is represented as a set of parallel stripes with two different amplitude reflectivity coefficients, is detected via diffraction of a laser beam in the reflection configuration. Due to the magnetic-field-induced plasticity effect, the grating persists on the MAE surface for at least 90 h if the magnetic field remains present. When the magnetic field is removed, the diffraction efficiency vanishes in a few minutes. The described effect is much more pronounced in MAE samples with larger content of iron filler (80 wt%) than in the samples with lower content of iron filler (70 wt%). A simple theoretical model is proposed to describe the observed dependence of the diffraction efficiency on the applied magnetic field. Possible applications of MAEs as magnetically reconfigurable diffractive optical elements are discussed. It is proposed that the described experimental method can be used as a convenient tool for investigations of the dynamics of magnetically induced plasticity of MAEs on the micrometer scale. KW - ADHESION KW - friction KW - magnetoactive elastomers KW - magnetorheological elastomer KW - optical diffraction KW - shape memory effect KW - surface microstructuring KW - TEMPERATURE Y1 - 2021 U6 - https://doi.org/10.3390/polym13244422 VL - 13 IS - 24 PB - MDPI ER - TY - CHAP A1 - Grabner, Christian A1 - Gragger, Johannes V. A1 - Kapeller, Hansjörg A1 - Haumer, Anton A1 - Kral, Christian ED - Ao, Sio-Iong ED - Gelman, Len T1 - Sensorless PM-Drive Aspects T2 - Electronic Engineering and Computing Technology N2 - The development procedure of permanent magnet drives for sensor less operation beginning from standstill under overload conditions has to consider different design aspects coevally. First, the robust rotor position sensing by test signal enforces a design with a strongly different behavior of the spatial dq-oriented differential inductance values. Therefore, the interior rotor magnet array arrangement is from principle predestinated for the controlled sensor less mode including standstill. Fortunately, in order to reduce costs, the distinct reluctance torque capability of such interior magnet arrangement is additionally used for a significantly increased torque by applying a pre-oriented stator current space vectors within the quasi-steady control. KW - inductance modeling KW - machine design KW - nonlinear saturation effects KW - Sensorless vector control Y1 - 2010 SN - 978-90-481-8775-1 SN - 978-90-481-8776-8 U6 - https://doi.org/10.1007/978-90-481-8776-8_3 SP - 25 EP - 35 PB - Springer CY - Dordrecht ER - TY - CHAP A1 - Drexler, C. A1 - Hirmer, Marion A1 - Danilov, Sergey N. A1 - Giglberger, Stephan A1 - Putzger, Jürgen A1 - Niklas, Andreas A1 - Jäger, Andreas A1 - Hiller, K.A A1 - Löffler, S. A1 - Schmalz, Gottfried A1 - Redlich, B. A1 - Schulz, Irene A1 - Monkman, Gareth J. A1 - Ganichev, Sergey D. T1 - Infrared spectroscopy for clinical diagnosis of dental pulp vitality T2 - 37th International Conference on Infrared, Millimetre, and Terahertz Waves (IRMMW-THz 37), 23-28 September 2012 , Wollongong, Australia N2 - Transmission spectra of wet human teeth and dentin slices, together with blood of different flow rates were investigated over a wide spectral range, from visible to terahertz (THz) light. The results make it possible to find the optimum light frequency for an all-optical determination of pulpal blood flow and, consequently, for clinically diagnosis of tooth vitality. Y1 - 2012 U6 - https://doi.org/10.1109/IRMMW-THz.2012.6380091 PB - IEEE CY - Piscataway, NJ ER - TY - CHAP A1 - Schulz, Irene A1 - Putzger, Jürgen A1 - Niklas, Andreas A1 - Brandt, M. A1 - Jäger, Andreas A1 - Hardt, A. A1 - Knörzer, S. A1 - Hiller, Karl-Anton A1 - Löffler, S. A1 - Schmalz, Gottfried A1 - Danilov, Sergey N. A1 - Giglberger, Stephan A1 - Hirmer, Marion A1 - Ganichev, Sergey D. A1 - Monkman, Gareth J. T1 - PPG signal acquisition and analysis on in vitro tooth model for dental pulp vitality assessmen T2 - 2nd Applied Research Conference 2012 (ARC 2012), 25./26. June 2012, Nuremberg Y1 - 2012 SP - 142 EP - 146 PB - Shaker-Verlag CY - Aachen ER - TY - CHAP A1 - Dötsch, Horst A1 - Holthaus, C. A1 - Trifonov, A. A1 - Klank, M. A1 - Hagedorn, Oliver A1 - Shamonin (Chamonine), Mikhail A1 - Schützmann, J. T1 - Application of Magnetic Garnet Films for Magnetooptical Imaging of Magnetic Field Distributions T2 - MRS Online Proceedings Library N2 - Rare-earth iron garnet films of high quality can be grown by liquid phase epitaxy on paramagnetic substrates of gadolinium galliumgarnet. Such films are currently used for imaging of the spatial distribution of magnetic fields. This application is based on the Faraday rotation which can strongly be enhanced by bismuth incorporation. The physical properties of the films can be controlled by the chemical composition, the growth conditions and the crystallographic orientation. The sensor properties like sensitivity, dynamic range, signal linearity and unambiguity must be optimized according to the application desired. These properties, however, are not independent of each other. In addition, they strongly depend on the optical wavelength. Thus, it is necessary to find compromises. The influence of Faraday rotation, Faraday ellipticity, optical absorption, magnetic anisotropies and film thickness on the performance of a magnetooptical indicator film is investigated. Based on the swing of the photoresponse, a new optimization process is introduced. The process is experimentally verified and application examples are demonstrated. Furthermore, two methods are presented to enhance the sensitivity of magnetooptical sensors. Using specific crystallographic orientations, an easy plane of magnetization can be induced which is inclined with respect to the film plane. If the magnetization lies in this plane a very high sensitivity is achieved. The dependence of the geometrical orientation of the easy plane on the growth direction is calculated and the sensitivity and dynamic range are derived. Experimental results of a [112] oriented garnet film are in good agreement with calculations. Garnet films which are magnetized along the film normal due to a strong induced uniaxial anisotropy support magnetic domains. If the collapse field perpendicular to the film plane is small, such films can be used as very sensitive indicator films. Such films are easier to prepare than sensitive in-plane films. However, the spatial resolution is limited by the size of the domains. This disadvantage can be avoided by applying a bias field in the film plane. Directly at the in-plane collapse field the sensor film is in-plane magnetized yielding high spatial resolution at still high sensitivity. The variation of magnetooptical images with in-plane induction is demonstrated. Experimental results are in agreement with calculations. Y1 - 2004 U6 - https://doi.org/10.1557/PROC-834-J6.1 SP - 18 EP - 29 PB - Springer ER - TY - JOUR A1 - Klank, M. A1 - Hagedorn, Oliver A1 - Holthaus, C. A1 - Shamonin (Chamonine), Mikhail A1 - Dötsch, Horst T1 - Characterization and optimization of magnetic garnet films for magneto-optical visualization of magnetic field distributions JF - NDT & E International N2 - Rare-earth iron garnet films with in-plane anisotropy grown on (111)-oriented substrates can be used as magneto-optical indicator films for visualization of magnetic leakage fields in nondestructive evaluation. The influence of Faraday rotation, Faraday ellipticity, absorption and film thickness on the performance of a magneto-optical indicator film is investigated. A new optimization method is introduced and compared with the method of contrast optimization. The theory is experimentally verified and an application example is presented. KW - Magneto-optics KW - Imaging KW - Magnetic flux leakage KW - Garnet films Y1 - 2003 U6 - https://doi.org/10.1016/S0963-8695(03)00012-4 VL - 36 IS - 6 SP - 375 EP - 381 PB - Elsevier ER - TY - JOUR A1 - Glavan, Gašper A1 - Belyaeva, Inna A. A1 - Drevenšek-Olenik, Irena A1 - Shamonin (Chamonine), Mikhail T1 - Experimental study of longitudinal, transverse and volume strains of magnetoactive elastomeric cylinders in uniform magnetic fields JF - Journal of Magnetism and Magnetic Materials N2 - Magnetoactive elastomers (MAEs) are promising materials for realization of magnetic field-controlled soft actuators. Herein, a systematic investigation of magnetic field-induced macroscopic deformations of soft MAE cylinders with a diameter of 15 mm in uniform quasi-static magnetic fields directed parallel to the cylinder’s axis is reported. The measurements were based on image processing. Thirty-six MAE samples differing in the weight fraction of the iron filler (70 wt%, 75 wt% and 80 wt%), alignment of filling particles, and the aspect ratio (0.2, 0.4, 0.6, 0.8, 1.0 and 1.2) were fabricated. MAE cylinders exhibited high relative change in height (up to 35% in the field of 485 kA/m) and lateral contraction. The dependence of the maximum extensional strain on the aspect ratio was obtained and compared with theoretical considerations. A concave dent was formed on the free circular base in magnetic fields. This concavity was characterized experimentally. A significant volumetric strain of the order of magnitude of 10% was calculated in MAEs for the first time. In consequently repeated magnetization cycles, the remanent extensional strain significantly increased after each cycle. The results are qualitatively discussed in the framework of the modern views on the magnetically induced macroscopic deformations of MAEs. The directions of further research are outlined. Y1 - 2023 U6 - https://doi.org/10.1016/j.jmmm.2023.170826 SN - 0304-8853 VL - 579 PB - Elsevier ER - TY - CHAP A1 - Schaller, R. A1 - Maier, F. A1 - Mandl, Roland T1 - Thermally stimulated depolarization current - characterization of a multi-layer dielectric stack for semiconductor packages T2 - 2022 14th International Conference on Advanced Semiconductor Devices and Microsystems (ASDAM), 23-26 October 2022, Smolenice Castle, Slovakia N2 - In this paper, the results of Thermally Stimulated Depolarization Currents (TSDC)-measurements of a complex system of stacked dielectric layers, like typically appearing in semiconductor packages, is presented. Characteristics of the individual isolation layers are presented solely and the results are compared to the stack. The investigated layers are comprising polyimide film, alkali-free glass, polyolefin film and epoxy based mold compound. Measurements have been carried out in the temperature range from 19 - 195°C at varying polarization fields for every material. Various relaxation peaks, originated by different polarization mechanisms within the materials could be observed. A comparison between the TSDC-peaks of the layer stack and the individual materials is shown. Our results demonstrate, that the super positioned spectrum is getting dominated by a single portion, the mold compound. KW - Glass KW - Micromechanical devices KW - Polyimides KW - Semiconductor device measurement KW - Semiconductor devices KW - Temperature distribution KW - Temperature measurement Y1 - 2022 SN - 978-1-6654-6977-7 U6 - https://doi.org/10.1109/ASDAM55965.2022.9966799 SP - 1 EP - 5 PB - IEEE ER - TY - CHAP A1 - Meier, Hans A1 - Reindl, Andrea A1 - Wetzel, Daniel A1 - Niemetz, Michael T1 - Comparative Analysis of CAN, CAN FD and Ethernet for Networked Control Systems T2 - Embedded World 2021 Exhibition & Conference: 1.-5.3.2021, digital, conference proceedings N2 - Networked control systems as e.g., battery management systems, smart grids or vehicular systems, consist of sensors, actuators and controllers with a communication network in the control loop. The data rate and the reliability of the underlying communication network are key factors since delays or message losses directly affect the system control. In addition, the processor load caused by the communication is significant as it influences the calculation of system states and the setting of control parameters. The power consumption of the communication network has a further impact on the energy efficiency of the respective application. In this paper, the communication technologies Controller Area Network (CAN), Controller Area Network Flexible Data-rate (CAN FD) and Ethernet are compared in the context of networked control systems with focus on a decentralized battery management system. First, the message processing time and the processor load are measured. With regard to energy efficiency, the maximum power consumption is determined. The Bit Error Rates (BER) and the Residual Error Rates (RER) are calculated to evaluate the reliability. Finally, the receive FIFO load under high traffic conditions is examined. Index Terms—Networked control systems, decentralized battery management system, microcontrollers, communication systems, Ethernet, Controller Area Network (CAN), Controller Area Network Flexible Data-rate (CAN FD) energy efficiency, energy consumption, bit error rate, residual error rate, processor load. Y1 - 2021 UR - https://www.researchgate.net/publication/354995738_Comparative_Analysis_of_CAN_CAN_FD_and_Ethernet_for_Networked_Control_Systems/link/615706baa6fae644fbb85b95/download PB - WEKA Fachmedien ER - TY - CHAP A1 - Reindl, Andrea A1 - Wetzel, Daniel A1 - Niemetz, Michael A1 - Meier, Hans T1 - Leader Election in a Distributed CAN-Based Multi-Microcontroller System T2 - 2023 3rd International Conference on Electrical, Computer, Communications and Mechatronics Engineering (ICECCME), 19-21 July 2023, Tenerife, Canary Islands, Spain N2 - In a distributed system, functionally equivalent nodes work together to form a system with improved availability, reliability and fault tolerance. Thereby, the purpose is to achieve a common control objective. As multiple components cooperate to accomplish tasks, coordination between them is required. Electing a node as the temporary leader can be a possible solution to perform coordination. This work presents a self-stabilizing algorithm for the election of a leader in dynamically reconfigurable bus topology-based broadcast systems with a message and time complexity of O(1). The election is performed dynamically, i.e., not only when the leader node fails, and is criterion-based. The criterion used is a performance related value which evaluates the properties of the node regarding the ability to perform the tasks of the leader. The increased demands on the leader are taken into account and a re-election is started when the criterion value drops below a predefined level. The goal here is to distribute the load more evenly and to reduce the probability of failure due to overload of individual nodes. For improved system availability and reduced fault rates, a management level consisting of leader, assistant and co-assistant is introduced. This reduces the number of required messages and the duration in case of non-initial election. For further reduction of required messages to uniquely determine a leader, the CAN protocol is exploited. The proposed algorithm selects a node with an improved failure rate and a reduced message and hence time complexity while satisfying the safety and termination constraints. The operation of the algorithm is validated using a hardware test setup. KW - broadcast communication KW - computational complexity KW - controller area networks KW - coordination KW - decentralized applications KW - distributed systems KW - failure analysis KW - Fault tolerance KW - fault tolerant computing KW - Fault tolerant systems KW - Hardware KW - Heuristic algorithms KW - Leader election KW - load balancing KW - Mechatronics KW - message complexity KW - microcontrollers KW - performance related election KW - probability KW - Protocols KW - self-stabilization KW - telecommunication network topology KW - Voting Y1 - 2023 SN - 979-8-3503-2297-2 U6 - https://doi.org/10.1109/ICECCME57830.2023.10252250 SP - 1 EP - 8 PB - IEEE CY - Piscataway, NJ, USA ER - TY - JOUR A1 - Schiek, Roland T1 - Nonlinear refractive index in silica glass JF - Optical Materials Express N2 - The third-order nonlinear susceptibility of silica glass is measured via self-phase modulation in standard single mode fibers at a wavelength of 1550 nm. To minimize the influence of polarization state changes along the propagation only meter-long fibers were investigated. With pulse durations of picoseconds a quasi-instantaneous nonlinearity with ultrafast electronic and fast nuclear-vibration contributions produces under conditions of negligible dispersion a classic and clean nonlinear phase shift following exactly the shape of the pulse power. The complex pulse envelope was retrieved from frequency optical gating spectrograms. The nonlinear fiber parameter γ could be determined with an accuracy of 3.7 percent. Considering the mode field structure and the doping influence the nonlinear refractive index of silica glass as the fiber base material was found to be n2 = 2.22 · 10−16 cm2 W ± 6.0 % for picosecond-long pulses. Comparing nonlinear phase shifts from linear and circular polarized light a nuclear-vibration contribution to the cubic fiber nonlinearity of 25 percent was estimated. Y1 - U6 - https://doi.org/10.1364/OME.489520 N1 - Corresponding author: Roland Schiek VL - 13 IS - 6 SP - 1727 EP - 1740 PB - Optica Publishing Group ER - TY - CHAP A1 - Reindl, Andrea A1 - Lausser, Florian A1 - Eriksson, Lars A1 - Park, Sangyoung A1 - Niemetz, Michael A1 - Meier, Hans ED - Pinker, Jiří T1 - Control Oriented Mathematical Modeling of a Bidirectional DC-DC Converter - Part 1: Buck Mode T2 - 28th International Conference on Applied Electronics (AE) 2023, Pilsen, 6-7 September 2023 N2 - Parallel connection of different batteries equipped with bidirectional DC-DC converters offers an increase of the total storage capacity, the provision of higher currents and an improvement of reliability and system availability. To share the load current among the DC-DC converters while maintaining the safe operating range of the batteries, appropriate controllers are needed. The basis for the design of these control approaches requires knowledge of both the static and dynamic characteristics of the DC-DC converter used. In this paper, the small signal analysis of a DC-DC converter in buck mode is shown using the circuit averaging technique. The paper gives an overview of all required transfer functions:. The control and line to output transfer functions for CCM and DCM relevant for average current mode control as well as for voltage control are derived and their poles and zeros are determined. This provides the basis for stability consideration, analysis of the overall control structure and controller design. KW - Analytical models KW - Average modeling KW - Batteries KW - bidirectional dc-dc converter KW - buck mode KW - circuit-averaging technique KW - continuous conduction mode KW - DC-DC power converters KW - derivation of transfer functions KW - discontinuous conduction mode KW - half-bridge KW - Mathematical models KW - Reliability KW - Signal analysis KW - small signal analysis KW - Stability analysis Y1 - 2023 SN - 979-8-3503-3554-5 U6 - https://doi.org/10.1109/AE58099.2023.10274168 SP - 1 EP - 7 PB - University of West Bohemia CY - Pilsen ER - TY - JOUR A1 - Schubert, Martin J. W. A1 - Höfflinger, Bernd A1 - Zingg, René P. T1 - An Analytical Model for Strongly Inverted and Accumulated Silicon Films JF - Solid-State Electronics N2 - An analytical model for the spatial distribution of potential, electric field and carrier densities is presented, assuming uniform doping density and constant quasi-Fermi potentials in the direction of modeling. Starting from the current relations a differential equation respecting two-dimensional effects is developed and solved approximately by decomposition in three regions with different preconditions: (a) flatband region, (b) constant spacecharge density and (c) strong inversion or accumulation. Inaccuracies arise mainly from violated preconditions at the interfaces between the different regions. Two-dimensional effects are respected in the analytical model of (b) only but they influence region (c) by means of boundary conditions at the interface of (b) and (c). The investigations of this paper are focused to region (c). This part of our model is identical to the model of Hauser and Littlejohn[1]. They integrated a simplified form of the semiconductor-Poisson equation twice but were restricted to one-dimensional applications and thermal equilibrium. Our derivation allows for large electric fields and current densities perpendicular to the direction of modeling. From analytical considerations confirmed by numerical experiments we suggest preference to the gradual channel condition, with x and y defined according to Fig. 1. This definition allows the potentials to vary significantly with respect to y. We found that this holds for the quasi-Fermi potentials also. Furthermore an empirical model for the maximum width of strong-inversion layers in uniformly doped silicon films is presented in eqn (46). Y1 - 1990 U6 - https://doi.org/10.1016/0038-1101(90)90136-3 VL - 33 IS - 12 SP - 1553 EP - 1567 PB - Elsevier ER - TY - CHAP A1 - Declerq, Michel A1 - Schubert, Martin J. W. A1 - Clément, F. T1 - 5V-to-75V CMOS Output Interfaces T2 - Proceedings of the1993 IEEE International Solid-State Circuits Conference (ISSCC), Feb. 24-26 1993, San Francisco, CA, USA N2 - A family of CMOS low- to high-voltage output interface circuits based on a standard, unmodified low-voltage CMOS technology is described. Using only thin-oxide high-voltage (HV) devices with reduced V/sub GS/ (gate-to-source voltage) swing, it makes use of level-shift techniques to meet the constraints on the gate control signals. These static circuits permit the full output voltage swing of V/sub DDH/, while keeping the V/sub GS/ swing of the output devices within the safety limits, including during HV supply transients. Using a standard 2- mu m n-well CMOS technology, reliable, reproducible V/sub DS/ breakdown voltages as high as 120 V and 80 V have been obtained for HV-nMOS and HV-pMOS devices, respectively.< > Y1 - 1993 U6 - https://doi.org/10.1109/ISSCC.1993.280014 SP - 162 EP - 163 ER - TY - CHAP A1 - Declerq, Michel A1 - Clément, F. A1 - Schubert, Martin J. W. A1 - Harb, Adnan A1 - Dutoit, Michel T1 - Design and Optimization of High-Voltage CMOS Devices Compatible wih a Standard 5V CMOS Technology T2 - Proceedings of IEEE Custom Integrated Circuits Conference, May 9-12 1993, San Diego, CA, USA N2 - High-voltage n- and p-MOSFETs fully compatible with a standard 5 V CMOS technology have been designed, optimized, and fabricated. No process changes are required. By modifying the logical equations generating one of the physical masks from the design masks, a p-type buffer region for the high-voltage p-MOS was easily implemented. This modification does not affect the low-voltage part of the circuits. These high-voltage devices have been used successfully as output drivers in semicustom arrays, and as building blocks for custom low- to high-voltage output interfaces. Aspects of reliability, device protection, and circuit design techniques are addressed. Y1 - 1993 SN - 0-7803-0826-3 U6 - https://doi.org/10.1109/CICC.1993.590766 SP - 24.6.1 EP - 24.6.4 ER - TY - JOUR A1 - Schubert, Martin J. W. A1 - Höfflinger, Bernd A1 - Zingg, René P. T1 - A One-Dimensional Analytical Model for the Dual-Gate-Controlled Thin-Film SOI MOSFET JF - IEEE Electron Device Letters N2 - A one-dimensional analytical model for dual-gate-controlled SOI MOSFETs is presented and applied to a stacked p-channel MOSFET fabricated by epitaxial lateral overgrowth (ELO). The authors found and modeled a nonlinear dependence of front-gate threshold voltage on back-gate voltage if threshold is defined by a constant current instead of a constant silicon-surface potential. It is demonstrated by comparison of subthreshold slopes that surface potentials are not pinned to the onset of strong inversion or accumulation. Accurate one-dimensional modeling is a necessity for device characterization and a precondition for general SOI models for circuit simulation.< > Y1 - 1991 U6 - https://doi.org/10.1109/55.116927 VL - 12 IS - 9 SP - 489 EP - 491 ER - TY - PAT A1 - Declerq, Michel A1 - Schubert, Martin J. W. T1 - Circuit Intermédiaire entre un Circuit Logique à Basse-Tension et un Etage de Sortie à Haute-Tension Réalisés dans une Technologie CMOS Standard N2 - La présente invention concerne un circuit intermédiaire entre un circuit logique a basse tension et un étage de sortie à haute tension réalisés dans une technologie CMOS standard. L'étage de sortie (20) comporte deux transistors respectivement à canal N et à canal P, réalisés selon une technologie CMOS standard. Le circuit intermédiaire comporte un translateur de niveau de tension (21) couplé entre un circuit logique d'entrée SL et ledit étage de sortie (20). Ce translateur de niveau de tension (21) est réalisé selon une technologie CMOS standard et est constitué d'au moins deux blocs de base identiques formant des miroirs de tension interconnectés de façon croisée. Ce circuit est utilisé pour commander des transducteurs, des écrans plasma et des actionneurs électromécaniques. Y1 - 1992 ER - TY - JOUR A1 - Reindl, Klaus A1 - Zheng, Yuanhang A1 - Schwarz, Andreas A1 - Meier, Stefan A1 - Maas, Roland A1 - Sehr, Armin A1 - Kellermann, Walter T1 - A stereophonic acoustic signal extraction scheme for noisy and reverberant environments JF - Computer Speech and Language N2 - In this contribution, a novel two-channel acoustic front-end for robust automatic speech recognition in adverse acoustic environments with nonstationary interference and reverberation is proposed. From a MISO system perspective, a statistically optimum source signal extraction scheme based on the multichannel Wiener filter (MWF) is discussed for application in noisy and underdetermined scenarios. For free-field and diffuse noise conditions, this optimum scheme reduces to a Delay & Sum beamformer followed by a single-channel Wiener postfilter. Scenarios with multiple simultaneously interfering sources and background noise are usually modeled by a diffuse noise field. However, in reality, the free-field assumption is very weak because of the reverberant nature of acoustic environments. Therefore, we propose to estimate this simplified MWF solution in each frequency bin separately to cope with reverberation. We show that this approach can very efficiently be realized by the combination of a blocking matrix based on semi-blind source separation (‘directional BSS’), which provides a continuously updated reference of all undesired noise and interference components separated from the desired source and its reflections, and a single-channel Wiener postfilter. Moreover, it is shown, how the obtained reference signal of all undesired components can efficiently be used to realize the Wiener postfilter, and at the same time, generalizes well-known postfilter realizations. The proposed front-end and its integration into an automatic speech recognition (ASR) system are analyzed and evaluated in noisy living-room-like environments according to the PASCAL CHiME challenge. A comparison to a simplified front-end based on a free-field assumption shows that the introduced system substantially improves the speech quality and the recognition performance under the considered adverse conditions. KW - Blind source extraction KW - Speech enhancement KW - Robust automatic speech recognition KW - PASCAL CHiME challenge Y1 - 2013 U6 - https://doi.org/10.1016/j.csl.2012.07.011 VL - 27 IS - 3 SP - 726 EP - 745 PB - Elsevier ER - TY - CHAP A1 - Sehr, Armin A1 - Yoshioka, Takuya A1 - Delcroix, Marc A1 - Kinoshita, Keisuke A1 - Nakatani, Tomohiro A1 - Maas, Roland A1 - Kellermann, Walter T1 - Conditional emission densities for combining speech enhancement and recognition systems T2 - Proceedings of the Annual Conference of the International Speech Communication Association, INTERSPEECH, 25 - 29 August 2013, Lyon, France N2 - A novel framework based on conditional emission densities for hidden Markov models (HMMs) is proposed in this contribution to integrate speech enhancement systems with automatic speech recognition systems. In the training phase, the observed feature vectors, corrupted by background noise and reverberation, together with estimates for the interference as provided by the speech enhancement system are used for training joint densities of the observations and the interference estimates. In the decoding phase, the joint densities are transformed to conditional densities of the observed features given the interference estimates. Thus, front end processing can be exploited for obtaining interference estimates, and the estimation errors can be modeled very effectively in a data-driven way. Connected digit recognition experiments in a simulated reverberant environment show the potential of the proposed approach: HMMs with the proposed conditional densities outperform various configurations of conventional HMMs in the logarithmic melspectral domain. This is a first step towards using conditional densities for creating synergies between front end and back end. Index Terms: speech enhancement, robust speech recognition, dereverberation, conditional HMM emission densities, frame- by-frame model adaptation. Y1 - 2013 U6 - https://doi.org/10.21437/Interspeech.2013-265 SP - 3502 EP - 3506 PB - ISCA ER - TY - CHAP A1 - Maas, Roland A1 - Thippur, Akshaya A1 - Sehr, Armin A1 - Kellermann, Walter T1 - An uncertainty decoding approach to noise- and reverberation-robust speech recognition T2 - IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), 26-31 May 2013, Vancouver, BC, Canada : Proceedings N2 - The generic REMOS (REverberation MOdeling for robust Speech recognition) concept is extended in this contribution to cope with additional noise components. REMOS originally embeds an explicit reverberation model into a hiddenMarkov model (HMM) leading to a relaxed conditional independence assumption for the observed feature vectors. During recognition, a nonlinear optimization problem is to be solved in order to adapt the HMMs' output probability density functions to the current reverberation conditions. The extension for additional noise components necessitates a modified numerical solver for the nonlinear optimization problem. We propose an approximation scheme based on continuous piecewise linear regression. Connected-digit recognition experiments demonstrate the potential of REMOS in reverberant and noisy environments. They furthermore reveal that the benefit of an explicit reverberation model, overcoming the conditional independence assumption, increases with increasing signal-to-noise-ratios. KW - Hidden Markov models KW - Reverberation KW - Noise KW - Speech KW - Adaptation models KW - Vectors KW - Optimization Y1 - 2013 U6 - https://doi.org/10.1109/ICASSP.2013.6639098 SP - 7388 EP - 7392 PB - IEEE ER - TY - JOUR A1 - Sehr, Armin A1 - Barfuss, Hendrik A1 - Hofmann, Christian A1 - Maas, Roland A1 - Kellermann, Walter T1 - Efficient training of acoustic models for reverberation-robust medium-vocabulary automatic speech recognition JF - 2014 4th Joint Workshop on Hands-Free Speech Communication and Microphone Arrays, HSCMA, 12-14 May 2014, Villers-les-Nancy, France N2 - A recently proposed concept for training reverberation-robust acoustic models for automatic speech recognition using pairs of clean and reverberant data is extended from word models to tied-state triphone models in this paper. The key idea of the concept, termed ICEWIND, is to use the clean data for the temporal alignment and the reverberant data for the estimation of the emission densities. Experiments with the 5000-word Wall Street Journal corpus confirm the benefits of ICEWIND with tied-state triphones: While the training time is reduced by more than 90%, the word accuracy is improved at the same time, both for room-specific and multi-style hidden Markov models. Since the acoustic models trained with ICEWIND need less Gaussian components for the emission densities to achieve comparable recognition rates as Baum-Welch acoustic models, ICEWIND also allows for a reduced decoding complexity. KW - Hidden Markov models KW - Training KW - Speech recognition KW - Speech KW - Vectors KW - Accuracy KW - Training data Y1 - 2014 U6 - https://doi.org/10.1109/HSCMA.2014.6843275 SP - 177 EP - 181 PB - IEEE ER - TY - RPRT A1 - Michael Sterner, A1 - Mareike Jentsch, A1 - Uwe Holzhammer, T1 - Energiewirtschaftliche und ökologische Bewertung eines Windgas-Angebotes N2 - In this technical report, (1) the benefits of the new technology for future energy supply are discussed, (2) the climate protection effect of wind gas is discussed, and (3) a reasonable use of wind energy for gas generation is analyzed. In particular, windgas in the heat market is discussed in the utilization cascade of wind energy. The new "power-to-gas" concept opens up completely new possibilities for the integration of renewable energies and for coupling the electricity and gas grids. The Sabatier process, which has been known for 100 years, was first developed for this purpose in 2008 under the leadership of the Center for Solar Energy and Hydrogen Research and Fraunhofer IWES (formerly ISET) with electrolysis to create the "power-to-gas" concept for energy storage. A first pilot plant was built by ZSW Stuttgart on behalf of SolarFuel in 2009. This plant proves the technical feasibility of the new technology. Renewable gas is stored, transported and used as required as control and reserve energy via reconversion, e.g. in combined cycle power plants. In this way, decentrally generated renewable electricity is converted into a CO2 -neutral energy carrier with high energy density. The key advantage of renewable methane is the use of existing infrastructure such as gas grids, gas storage and end-use equipment for the integration of renewable energy. Technologies for natural gas are state of the art and commercially available. Methane also has three times the energy density of hydrogen. T2 - Energy-economic and ecological evaluation of a windgas offer (Power-to-Gas) Y1 - 2011 U6 - https://doi.org/10.13140/RG.2.2.25093.68328 PB - Fraunhofer Institute for Energy Economics and Energy System Technology CY - Kassel ER - TY - JOUR A1 - Shamonin (Chamonine), Mikhail A1 - Klank, M. A1 - Hagedorn, Oliver A1 - Dötsch, Horst T1 - Magneto-optical visualization of metal-loss defects in a ferromagnetic plate: experimental verification of theoretical modeling JF - Applied optics N2 - Rare-earth iron garnet films with in-plane magnetic anisotropy grown on [111]-oriented substrates are promising for the visualization of magnetic leakage fields in nondestructive evaluation. Such magneto-optical films have to be specifically engineered, and we give an example of this technology. To assess the validity and accuracy of finite-element calculations of a magnetization assembly combined with the physical modeling of the image formation, comparisons between calculated and experimentally obtained magneto-optical images of metal-loss defects have been made. A convincing quantitative agreement is demonstrated. It is shown that both physical and computer modeling techniques allow for a predictive engineering design of the prospective applications and provide greater insight into the method. Y1 - 2001 U6 - https://doi.org/10.1364/ao.40.003182 VL - 40 IS - 19 SP - 3182 EP - 3189 PB - Optica Publishing Group ER - TY - JOUR A1 - Shamonin (Chamonine), Mikhail A1 - Beuker, T. A1 - Rosen, P. A1 - Klank, M. A1 - Hagedorn, Oliver A1 - Dötsch, Horst T1 - Feasibility of magneto-optic flaw visualization using thin garnet films JF - NDT & E International N2 - We investigate the feasibility of using rare-earth iron garnet films grown on (111)-oriented substrates as magneto-optic indicator films for the visualization of magnetic leakage fields in non-destructive evaluation. In most cases the leakage field of the defect has a strong component in the film plane. The influence of this in-plane dc magnetic field on the image formation is investigated. It is shown that the presence of a strong in-plane magnetic field allows one to extend the dynamic range of the out-of-plane field imposed by the uniaxial anisotropy field HA. On the other hand, an in-plane field reduces the sensitivity. The guidelines for selecting parameters of magneto-optic indicator films are given. KW - Garnet films KW - Magneto-optics KW - Imaging KW - Flaw visualization KW - Magnetic flux leakage Y1 - 2000 U6 - https://doi.org/10.1016/s0963-8695(00)00028-1 VL - 33 IS - 8 SP - 547 EP - 553 PB - Elsevier ER - TY - JOUR A1 - Bakaev, V. V. A1 - Snarskii, Andrei A. A1 - Shamonin (Chamonine), Mikhail T1 - The effective magnetic permeability of a two-phase fibred ferromagnetic composite JF - Technical Physics Y1 - 2001 U6 - https://doi.org/10.1134/1.1427995 VL - 46 IS - 12 SP - 1571 EP - 1574 PB - Springer ER - TY - GEN A1 - Chavez, Jhohan A1 - Böhm, Valter A1 - Scharff, M. A1 - Prem, Nina A1 - Monkman, Gareth J. A1 - Becker, Tatiana I. A1 - Günther, L. A1 - Alencastre, Jorge H. A1 - Grieseler, R. A1 - Zimmermann, Klaus T1 - Magneto-active elastomer as viscoelastic foundation material for artificial tactile sensors with tuneable properties T2 - Book of Abstracts of the 16th German Ferrofluid Workshop, Braunschweig, 18.-20.07.2018 Y1 - 2018 SP - 16 EP - 17 ER - TY - JOUR A1 - Zimmermann, Klaus A1 - Böhm, Valter A1 - Becker T.I., A1 - Chavez, Jhohan A1 - Kaufhold, T. A1 - Monkman, Gareth J. A1 - Sindersberger, Dirk A1 - Diermeier, Andreas A1 - Prem, Nina T1 - Mechanical Characterization of the Field-Dependent Properties of Magnetoactive Polymers and Integrated Electrets for their Application in Soft Robotics JF - International Scientific Journal "Problems of Mechanics" Y1 - 2017 SN - 1512-0740 VL - 69 IS - 4 ER - TY - GEN A1 - Chavez, Jhohan A1 - Böhm, Valter A1 - Yin, J. A1 - Becker, Tatiana I. A1 - Köhring, S. A1 - Monkman, Gareth J. A1 - Odenbach, S. A1 - Zimmermann, Klaus T1 - Field induced plasticity of magneto-sensitive elastomers for gripping technology applications T2 - 6th Colloquium of SPP 1681, Benediktbeuern, 26. - 28.09.2018 : Book of Abstracts Y1 - 2018 SP - 16 EP - 17 ER - TY - JOUR A1 - Lohmeyer, M. A1 - Shamonin (Chamonine), Mikhail A1 - Hertel, P. T1 - Boundary conditions for the finite difference beam propagation method based on plane wave solutions of the Fresnel equation JF - IEEE Journal of Quantum Electronics N2 - Each particular implementation of the beam propagation method (BPM) requires a special procedure allowing for radiation to leave the computational window. We propose a new approach to constructing the finite difference schemes of the BPM at the boundary of the computational window. These schemes are independent of the computed fields and allow for a similar treatment of both interior and boundary points. The new approach can be further improved by correcting the field values at the boundary points according to Hadley's method. The algorithm is easy to implement for both two- and three-dimensional structures. The new method considerably reduces computation times because the propagation matrices remain constant in longitudinally invariant sections, thus avoiding repeated LU-decompositions. The basic idea-establishing the finite difference scheme such that locally exact, approximate, or plausible solutions are recovered-may be of interest for other efforts to solve partial differential equations by the finite difference method. KW - Boundary conditions KW - Finite difference methods KW - Optical propagation KW - Matrix decomposition KW - Computational modeling KW - Refractive index KW - Maxwell equations KW - Sparse matrices KW - Partial differential equations KW - Shape Y1 - 1997 U6 - https://doi.org/10.1109/3.552269 SN - 0018-9197 VL - 33 IS - 2 SP - 279 EP - 286 ER - TY - JOUR A1 - Shamonin (Chamonine), Mikhail A1 - Lohmeyer, M. A1 - Hertel, P. T1 - Analysis of power-dependent switching between radiatively coupled planar waveguides JF - Journal of Lightwave Technology N2 - Effective coupling between two remote optical waveguides without branching sections can be achieved in a three-guide system with multimode central waveguide. We investigate the nonlinear power switching of c.w. laser radiation by such radiatively coupled waveguides. It is shown that effective all-optical switches with spatially well separated input/output channels can be realized although the influence of multimode interference on the switching characteristics becomes more pronounced for increasing thickness of the central guide. Different coupling regimes are specified, and the changes in switching characteristics during the transformation from one regime to another is studied. Numerical calculations for the critical power are compared with an approximate analytical expression. It is also shown that, at a moderate input power, a small number of modes determines the switching behavior. KW - Electromagnetic coupling KW - Planar waveguide KW - Optical waveguides KW - Nonlinear optics KW - Optical coupling KW - Optical surface waves KW - Optical refraction KW - Optical variables control KW - Refractive index KW - Optical switches Y1 - 1997 UR - 1558-2213 U6 - https://doi.org/10.1109/50.588671 VL - 15 IS - 6 SP - 983 EP - 989 PB - IEEE CY - New York ER - TY - JOUR A1 - Lohmeyer, M. A1 - Shamonin (Chamonine), Mikhail A1 - Bahlmann, N. A1 - Hertel, P. A1 - Dotsch, H. T1 - Radiatively Coupled Waveguide Concept for an Integrated Magneto-Optic Circulator JF - MRS Online Proceedings Library N2 - Three-guide couplers with multimode central waveguides allow for remote coupling between optical channels. A simple three mode approximation turns out to be sufficient for the description of the main features of the power transfer behavior. The specific form of the relevant modes suggests the design of integrated optical isolators and circulators based on magnetic garnet materials. These novel devices are superior to conventional nonreciprocal couplers with respect to the total length and admissible fabrication tolerances. We characterize the isolation performance and the transmission loss for the proposed devices by propagating mode simulations and estimate the influence of geometry parameter deviations. Y1 - 1998 U6 - https://doi.org/10.1557/PROC-517-519 SN - 1946-4274 IS - 517 SP - 519 EP - 524 ER - TY - JOUR A1 - Shamonin (Chamonine), Mikhail A1 - Lohmeyer, M. A1 - Hertel, P. T1 - Directional coupler based on radiatively coupled waveguides JF - Applied optics (Appl. Opt.) N2 - We investigate a system of two waveguides with leaky modes sharing a common substrate (radiatively coupled waveguides). The main advantage of such a system is the possibility of remote coupling. A perturbation theory is developed for both TE and TM polarization. Numerical calculations of dispersion curves and of the coupling length allow us to determine the limitations of the perturbation theory. We study the influence of multimode interference on the process of beating by considering the propagation of a given initial field. Finally, we propose a new design for an effective, integrated optical TE-TM polarization splitter. Y1 - 1997 UR - https://opg.optica.org/ao/abstract.cfm?URI=ao-36-3-635 U6 - https://doi.org/10.1364/ao.36.000635 VL - 36 IS - 3 SP - 635 EP - 641 ER - TY - JOUR T1 - Energieforschung BT - geförderte Projekte 2020 bis 2022 N2 - Über uns Das Regensburg Center of Energy and Resources (RCER) bündelt seit 2012 die Aktivitäten der Ostbayerischen Technischen Hochschule Regensburg (OTH Regensburg) und der regionalen Wirtschaftsunternehmen auf dem Strategiefeld „Energie und Ressourcen“. Mission: Energieforschung: vernetzen, voranbringen, vermitteln Das RCER fördert die Vernetzung verschiedener Disziplinen der Energieforschung innerhalb der OTH Regensburg und mit externen Partnern (Firmen, Förderträgern, Forschungsinstitutionen, öffentlichen Einrichtungen). Das RCER ist Ihr Partner beim Voranbringen von Kooperationen und Forschungsvorhaben durch Unterstützung in der Antragsphase, bei der Einwerbung von Projektmitteln und Projektbegleitung im Energiebereich. Das RCER steht für die Vermittlung von Know-how, Basiswissen, aktuellen Fragen und den Technologietransfer rund um das Thema Energie zwischen Wissenschaft, Wirtschaft, Gesellschaft und Politik. Vision Wir sind Ihr erster Ansprechpartner und Motor für innovative Energieforschung. Werte Verlässlichkeit, Kompetenz, Verantwortungsbewusstsein.Regional verwurzelt und weltoffen Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-65422 PB - OTH Regensburg ET - Ausgabe 2023 ER - TY - GEN A1 - Sterner, Michael T1 - Strom - Wärme - Verkehr - Industrie: das Zusammenspiel der Sektoren über Power-to-X T2 - Deutscher Ingenieurtag 2021, Düsseldorf 20. Mai 2021 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Sektorenkopplung Y1 - 2021 PB - VDI-Verlag ER - TY - JOUR A1 - Snarskii, Andrei A. A1 - Shamonin (Chamonine), Mikhail A1 - Yuskevich, Pavel T1 - Effect of magnetic-field-induced restructuring on the elastic properties of magnetoactive elastomers JF - Journal of Magnetism and Magnetic Materials N2 - Composite materials where magnetic micrometer-sized particles are embedded into a compliant polymer matrix are known as magnetorheological (or magnetoactive) elastomers (MAEs). They are distinguished by huge variations in their physical properties, when in a magnetic field, which is commonly attributed to the restructuring of the filler. The process of the magnetic-field-induced restructuring in a magnetorheological elastomer is interpreted as progression towards percolation. Such a physical model was previously used to explain the dependence of the magnetic permeability and dielectric permittivity of MAEs on the magnetic field strength. Based on this hypothesis, the magnetorheological effect in MAEs is considered theoretically. The theoretical approach is built upon a self-consistent effective-medium theory for the elastic properties, extended to the variable (field dependent) percolation threshold. The proposed model allows one to describe the large variations (over several orders of magnitude) of the effective elastic moduli of these composite materials, known as the giant magnetorheological (MR) and field-stiffening effects. The existence of a giant magnetic Poisson effect is predicted. The relation of the proposed model to the existing theories of the MR effect in MAEs is discussed. The results can be useful for applications of MAEs in magnetic-field-controlled vibration dampers and isolators. Y1 - 2021 U6 - https://doi.org/10.1016/j.jmmm.2020.167392 IS - 517, January PB - Elsevier ER - TY - JOUR A1 - Thema, Martin A1 - Weidlich, Tobias A1 - Kaul, Anja A1 - Böllmann, Andrea A1 - Huber, Harald A1 - Bellack, Annett A1 - Karl, Jürgen A1 - Sterner, Michael T1 - Optimized biological CO2-methanation with a pure culture of thermophilic methanogenic archaea in a trickle-bed reactor JF - Bioresource Technology N2 - In this study, a fully automated process converting hydrogen and carbon dioxide to methane in a high temperature trickle-bed reactor was developed from lab scale to field test level. The reactor design and system performance was optimized to yield high methane content in the product gas for direct feed-in to the gas grid. The reaction was catalyzed by a pure culture of Methanothermobacter thermoautotrophicus IM5, which formed a biofilm on ceramic packing elements. During 600 h in continuous and semi-continuous operation in countercurrent flow, the 0.05 m3 reactor produced up to 95.3 % of methane at a methane production rate of 0.35 mCH43mR-3h-1. Adding nitrogen as carrier gas during startup, foam control and dosing of ammonium and sodium sulfide as nitrogen and sulfur source were important factors for process automation. KW - Biological methanation KW - Power-to-Gas KW - Reactor concept KW - Thermophilic archaea KW - Trickle-bed reactor Y1 - 2021 U6 - https://doi.org/10.1016/j.biortech.2021.125135 IS - 333 PB - Elsevier ER - TY - JOUR A1 - Gärtner, Sebastian A1 - Rank, Daniel A1 - Heberl, Michael A1 - Gaderer, Matthias A1 - Dawoud, Belal A1 - Haumer, Anton A1 - Sterner, Michael T1 - Simulation and Techno-Economic Analysis of a Power-to-Hydrogen Process for Oxyfuel Glass Melting JF - Energies N2 - As an energy-intensive industry sector, the glass industry is strongly affected by the increasingly stringent climate protection targets. As established combustion-based production systems ensure high process stability and glass quality, an immediate switch to low greenhouse gas emission processes is difficult. To approach these challenges, this work investigates a step-by-step integration of a Power-to-Hydrogen concept into established oxyfuel glass melting processes using a simulation approach. This is complemented by a case study for economic analysis on a selected German glass industry site by simulating the power production of a nearby renewable energy park and subsequent optimization of the power-to-hydrogen plant performance and capacities. The results of this study indicate, that the proposed system can reduce specific carbon dioxide emissions by up to 60%, while increasing specific energy demand by a maximum of 25%. Investigations of the impact of altered combustion and furnace properties like adiabatic flame temperature (+25 °C), temperature efficiency (∆ξ = −0.003) and heat capacity flow ratio (∆zHL = −0.009) indicate that pure hydrogen-oxygen combustion has less impact on melting properties than assumed so far. Within the case study, high CO2 abatement costs of 295 €/t CO2-eq. were determined. This is mainly due to the insufficient performance of renewable energy sources. The correlations between process scaling and economic parameters presented in this study show promising potential for further economic optimization of the proposed energy system in the future. KW - Power-to-Gas KW - Hydrogen KW - Electrolysis KW - Oxyfuel KW - Glass Industry Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-22713 N1 - Corresponding author: Sebastian Gärtner VL - 14 IS - 24 PB - MDPI ER - TY - JOUR A1 - Lohmeyer, Manfred A1 - Shamonin (Chamonine), Mikhail A1 - Hertel, Peter T1 - Integrated optical circulator based on radiatively coupled magneto-optic waveguides JF - Optical Engineering N2 - In a three-guide coupler with multimode central waveguide, more than two modes of the entire structure participate in the coupling between the outer waveguides. Using a three-mode approximation we found simple conditions for complete power transfer between the outer waveguides: the device length has to match certain multiples of the con- ventionally defined coupling length. The specific form of the relevant modes allows us to design a magneto-optic isolator or circulator with significantly reduced device length (as compared to the conventional nonreciprocal coupler). The performance of the proposed devices is simulated by propagating-mode calculations. Estimates for admissible fabrication tolerances for the layer thicknesses are presented. KW - integrated optics KW - magneto-optic circulator KW - magneto-optic isolator KW - radiatively coupled waveguides KW - three-guide coupler Y1 - 1997 U6 - https://doi.org/10.1117/1.601255 VL - 36 IS - 3 SP - 889 EP - 895 PB - SPIE ER - TY - CHAP A1 - Rasp, Franziska A1 - Eberlein, Ernst A1 - Perner, Bastian A1 - Roth-Mandutz, Elke A1 - Hipp, Susanne T1 - Enhanced 5G Sidelink Ranging Based on Carrier Aggregation T2 - 2023 13th International Conference on Indoor Positioning and Indoor Navigation (IPIN), Nuremberg, Germany, 25-28 September 2023 N2 - Radio access network based positioning and ranging technologies become more and more important for autonomous driving. Positioning on the 5G Sidelink (SL) is discussed in Release 18 (2022-2024) of the Third Generation Partnership Project. For accurate timing-based ranging, a high temporal and spatial resolution is fundamental. The bandwidth for 5G SL positioning is limited due to sharing the existing SL resources with communication. Therefore, we send the positioning reference signal on two separate Component Carriers, i.e. we use a fragmented spectrum. We introduce a two step algorithm for estimating the time of arrival using the inflection point method. We proved a fragmented spectrum can achieve the same accuracy as a continuous spectrum. KW - Sidelink KW - 5G mobile communications KW - Distance measurement KW - Ranging KW - Positioning Y1 - 2023 SN - 9798350320114 U6 - https://doi.org/10.1109/IPIN57070.2023.10332548 SP - 1 EP - 6 PB - IEEE ER - TY - THES A1 - Marterer, Verena T1 - Simulation der elektromagnetischen Eigenschaften von gestricktem Stoff N2 - Periodische Strukturen besitzen eine Reihe interessanter Eigenschaften, die sie unter anderem für den Einsatz im Bereich der Hochfrequenz- und Mikrowellentechnik attraktiv erscheinen lassen. In der vorliegenden Arbeit steht insbesondere deren Anwendung beim Entwurf gestrickter Stoffe, die auf metallischen Fäden basieren, im Vordergrund. Es wird in diesem Zusammenhang zunächst die vollständige Modellierung der Struktur unter Verwendung von 3D-Elementen in repräsentativen Elementarzellen durchgeführt. Innerhalb der Designumgebung von CST Studio Suite kann das analytische Elementarmodell von Leaf und Glaskin für die Einfaden-Maschenware implementiert werden. Abhängig von den variablen Faktoren beim Stricken bewegen sich die Kantenlängen der hier betrachteten Einheitszelle in der Größenordnung von 1 cm bis 2 cm. Bei der Analyse der elektromagnetischen Eigenschaften unter Verwendung eines Frequenzbereichslösers können somit die Streuparameter für Reflexion und Transmission in einem Frequenzbereich von 13 GHz bis 30 GHz ermittelt werden. Aus den 1D-Simulationsergebnissen werden Frequenzen sichtbar, bei denen Resonanzphänomene auftreten. Die polarisationsabhängigen Strukturen weisen Abschirmwirkungen von 30 dB und mehr auf. Da das Resonanzverhalten mit den Oberflächenströmen in Verbindung steht, wird die Oberflächenstromverteilung zeitgleich mit dem elektrischen Feld untersucht. Weiterhin wird den Wechselwirkungen zwischen den veränderlichen Strickparametern und den elektromagnetischen Spezifikationen wie Resonanzfrequenz, Bandbreite oder Güte Aufmerksamkeit geschenkt. Es wird deutlich, dass Optimierungsroutinen die Möglichkeit nahelegen, frequenzselektive gestrickte Strukturen für diverse Anwendungen maßzuschneidern. Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-57605 CY - Regensburg ER - TY - THES A1 - Marterer, Verena T1 - A Characterisation of Motives and Barriers to Taking up Academic Study in the Field of Electrical Engineering N2 - The problem description comes to the fore when the wide-ranging subject area of electrical engineering is combined and analyzed with different types of schools. It is becoming increasingly rare for elementary school children to come to grips with technology in the sense of recognizing functional interrelationships and understanding modes of action in the context of technical-practical confrontation. The picture at secondary schools is also rather sobering. Here, a strong focus on facts and knowledge and too little emphasis on modeling, application and problem solving lead to insufficient results in the cognitive area. In addition, a massive shortage of engineers and specialists with a technical and scientific orientation has been predicted for years and is being increasingly observed. The motivation of students in traditional lectures is decreasing and in general there is a decline of university students in technical subjects. These problems are not only known throughout Germany, but also internationally. Especially in developing countries, additional problems make technical education more difficult, regardless of the type of school. Therefore, this master thesis is evaluated in South Africa in order to consider as many influencing factors as possible. "Learning is experience. Everything else is simply information." - Methods and concepts developed in the thesis build upon this quote of Albert Einstein. Teaching methods are elaborated and applied for three different age groups and school types, depending on known influencing factors. The aim of this thesis is not to produce further findings in the sense of basic research, but to show ways in which the current situation can be steered in a different direction. It has been shown that technology lessons in elementary/secondary schools inspire interest in technical professions in the field of electrical engineering. Furthermore, the combination of frontal teaching, for a necessary theoretical background, together with student-active, action-oriented teaching shows advantages in terms of learning efficiency and an increase in performance levels for all three age groups. However, it could also be observed that factors such as social background, family influence and gender have partial effects on the promotion and education in the field of electrical engineering. Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-62550 CY - Regensburg ER - TY - CHAP A1 - Tremmel, Florian A1 - Nagler, O. A1 - Kutter, C. A1 - Holmer, Rainer T1 - Smart Cantilever Probe with Integrated Force and Acoustic Emission Sensor T2 - 2023 IEEE SENSORS, Vienna, Austria, 10/29/2023 - 11/1/2023 N2 - Acoustic emission (AE) testing recently found its application in the wafer testing sector of the semiconductor industry. To find out the mechanical robustness of semiconductor devices, contact pads on the chip surface are intentionally overstressed with an indenter tip and the appearing oxide cracks are detected with help of the generated AE signals. This is done in a customized test bench with a patented sensor-indenter system. This paper presents an improved version of the measurement setup that solves certain disadvantages of it and can be used in a standard wafer prober. The main components of the developed sensor system are a strain gauge for contact force measurement and a piezoelectric sensor element for AE signal detection. Both components are integrated on a cantilever beam which has an exchangeable indenter tip at its free end. The cantilever probe is electrically conductive to enable electrical tests via the indenter tip. This smart sensor-cantilever combination (SCC) can be mounted with several adapter components on a carrier plate to place it in a wafer prober. For both sensor elements amplifier circuits are developed to enhance their signal-to-noise ratios (SNRs). A prototype setup is shown together with simulated and experimental results to demonstrate its performance. The mechanical properties of the cantilever, as well as the force sensor and the AE crack signals, already fulfill the requirements for an implementation in a wafer prober. To further improve the sensor resolutions and detection limits, several optimizations regarding the design of the SCC are in progress. KW - Acoustic emission testing KW - piezoelectric sensor KW - strain gauge KW - operational amplifier circuit Y1 - 2023 SN - 979-8-3503-0387-2 U6 - https://doi.org/10.1109/SENSORS56945.2023.10325021 SP - 1 EP - 4 PB - IEEE ER - TY - GEN A1 - Gegenfurtner, Andreas A1 - Boucheix, Jean-Michel A1 - Gruber, Hans A1 - Hauser, Florian A1 - Lehtinen, Erno A1 - Lowe, Richard K. T1 - Der Gaze Relational Index als Indikator visueller Expertise T2 - 51. Kongress der Deutschen Gesellschaft für Psychologie : 15. bis 20. September 2018, Goethe-Universität Frankfurt am Main, Campus Westend N2 - Eye tracking is a powerful technique that helps reveal how people process visual information. This paper discusses a novel metric for indicating expertise in visual information processing. Named the Gaze Relational Index (GRI), this metric is defined as the ratio of mean fixation duration to fixation count. Data from two eye-tracking studies of professional vision and visual expertise in using 3D dynamic medical visualizations are presented as cases to illustrate the suitability and additional benefits of the GRI. Calculated values of the GRI were higher for novices than for experts, and higher in non-representative, semi-familiar / unfamiliar task conditions than in domain-representative familiar tasks. These differences in GRI suggest that, compared to novices, experts engaged in more knowledge-driven, top-down processing that was characterized by quick, exploratory visual search. We discuss future research aiming to replicate the GRI in professional domains with complex visual stimuli and to identify the moderating role of cognitive ability on GRI estimates. Y1 - 2020 SN - 2573-2773 SP - 402 ER - TY - JOUR A1 - Gegenfurtner, Andreas A1 - Boucheix, Jean-Michel A1 - Gruber, Hans A1 - Hauser, Florian A1 - Lehtinen, Erno A1 - Lowe, Richard K. T1 - The gaze relational index as a measure of visual expertise JF - Journal of Expertise N2 - Eye tracking is a powerful technique that helps reveal how people process visual information. This paper discusses a novel metric for indicating expertise in visual information processing. Named the Gaze Relational Index (GRI), this metric is defined as the ratio of mean fixation duration to fixation count. Data from two eye-tracking studies of professional vision and visual expertise in using 3D dynamic medical visualizations are presented as cases to illustrate the suitability and additional benefits of the GRI. Calculated values of the GRI were higher for novices than for experts, and higher in non-representative, semi-familiar / unfamiliar task conditions than in domain-representative familiar tasks. These differences in GRI suggest that, compared to novices, experts engaged in more knowledge-driven, top-down processing that was characterized by quick, exploratory visual search. We discuss future research aiming to replicate the GRI in professional domains with complex visual stimuli and to identify the moderating role of cognitive ability on GRI estimates. KW - eye tracking KW - fixations KW - information processing KW - professional vision KW - visual expertise Y1 - 2020 UR - https://www.journalofexpertise.org/articles/volume3_issue1/JoE_3_1_Gegenfurtner.pdf SN - 2573-2773 VL - 3 IS - March SP - 32 EP - 40 PB - Michigan State University ER - TY - GEN A1 - Reuter, Rebecca A1 - Langer, Thomas A1 - Hauser, Florian A1 - Muckelbauer, Daniel A1 - Gegenfurtner, Andreas T1 - Automatic generation of areas of interest in eye tracking: The case of software engineering T2 - Earli Book of Abstracts Y1 - 2019 UR - https://earli.org/sites/default/files/2019-09/BOA-2019.pdf PB - RWTH Aachen ER - TY - GEN A1 - Kriegl, Raphael A1 - Kravanja, Gaia A1 - Hribar, Luka A1 - Jezeršek, Matija A1 - Drevenšek-Olenik, Irena A1 - Shamonin (Chamonine), Mikhail T1 - Characterization of Wetting Properties of Magnetoactive Elastomer Surfaces T2 - Proceedings of the ASME Conference on Smart Materials, Adaptive Structures and Intelligent Systems (SMASIS) - 2023, September 11–13, 2023 Austin, Texas, USA N2 - Commercially available contact angle (CA) measuring devices usually do not allow for the application of magnetic fields to the sample under test. A setup for measuring the CA of liquids on magnetosensitive surfaces has been developed specifically for investigating the surfaces of magnetoactive elastomers (MAEs). The addition of a programmable linear stage, which moves a permanent magnet, allows for fine control of the magnetic field applied to the MAE without the need for large and power-consuming electromagnets. Paired with a custom control and evaluation software, this measurement setup operates semiautomatically, limiting operator error and increasing precision, speed, as well as repeatability of static and dynamic CA measurements for different magnetoactive materials. The software is equipped with robust droplet fitting algorithms to avoid experimental challenges arising with soft magnetoactive materials, such as the curling of sample edges or diffuse non-reflective surfaces. Several application examples on MAE surfaces, both processed and unprocessed, are presented. KW - magnetoactive elastomers KW - image processing KW - droplet contour fitting KW - contact angle Y1 - 2023 SN - 978-0-7918-8752-3 U6 - https://doi.org/10.1115/SMASIS2023-110998 N1 - Corresponding author: Raphael Kriegl PB - The American Society of Mechanical Engineers CY - New York, USA ER - TY - JOUR A1 - Thema, Martin A1 - Bauer, Franz A1 - Sterner, Michael T1 - Power-to-Gas: Electrolysis and methanation status review JF - Renewable and Sustainable Energy Reviews N2 - This review gives a worldwide overview on Power-to-Gas projects producing hydrogen or renewable substitute natural gas focusing projects in central Europe. It deepens and completes the content of previous reviews by including hitherto unreviewed projects and by combining project names with details such as plant location. It is based on data from 153 completed, recent and planned projects since 1988 which were evaluated with regards to plant allocation, installed power development, plant size, shares and amounts of hydrogen or substitute natural gas producing examinations and product utilization phases. Cost development for electrolysis and carbon dioxide methanation was analyzed and a projection until 2030 is given with an outlook to 2050. The results show substantial cost reductions for electrolysis as well as for methanation during the recent years and a further price decline to less than 500 euro per kilowatt electric power input for both technologies until 2050 is estimated if cost projection follows the current trend. Most of the projects examined are located in Germany, Denmark, the United States of America and Canada. Following an exponential global trend to increase installed power, today's Power-to-Gas applications are operated at about 39 megawatt. Hydrogen and substitute natural gas were investigated on equal terms concerning the number of projects. KW - Biological CO2-Methanation KW - Chemical CO2-Methanation KW - Cost-development KW - Electrolysis KW - Power-to-Gas Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-26238 N1 - Corresponding author: Martin Thema VL - 112 IS - 7 SP - 775 EP - 787 PB - Elsevier ER - TY - JOUR A1 - Kovalev, Alexander A1 - Belyaeva, Inna A. A1 - von Hofen, Christian A1 - Gorb, Stanislav A1 - Shamonin (Chamonine), Mikhail T1 - Magnetically Switchable Adhesion and Friction of Soft Magnetoactive Elastomers JF - Advanced Engineering Materials N2 - Herein, the effect of an applied moderate (~240 mT) magnetic field on the work of adhesion (WoA) of mechanically soft (the shear modulus ~10 kPa) magnetoactive elastomer (MAE) samples with two different mass fractions (70 and 80 wt%) of carbonyl iron powder (CIP) is concerned. The unfilled elastomer sample is used for comparison. Due to some sedimentation of filling particles, the concentration of inclusions in thin (~10 μm) subsurface layers is different. It is shown that the WoA increases (up to 1.8-fold) on the particle-enriched side (PES) in the magnetic field and its value is higher for higher filler concentration. On the particle-depleted side (PDS), WoA does not depend on particle concentration and on the magnetic field. Adhesion and friction are coupled in MAEs. No statistically significant difference in the friction coefficient, determined from the extended Amontons´ law, depending on sample side, CIP concentration, or presence of magnetic field is found. However, the PDS in the magnetic field demonstrates significantly higher critical shear stress compared to that for the PES or PDS in the absence of magnetic field. Correlations between different surface properties are discussed. Obtained results are useful for the development of magnetically controllable soft robots. Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-45283 N1 - Corresponding authors: Stanislav Gorb und Mikhail Shamonin VL - 24 IS - 10 SP - 1 EP - 8 PB - WILEY-VCH ER - TY - JOUR A1 - Monkman, Gareth J. A1 - Sindersberger, Dirk A1 - Prem, Nina T1 - Magnetically enhanced photoconductive high voltage control JF - ISSS Journal of Micro and Smart Systems N2 - The recent surge of interest in electrostatic actuators, particularly for soft robotic applications, has placed increasing demands on high voltage control technology. In this respect, optoelectronic bidirectional switching and analogue regulation of high voltages is becoming increasingly important. One common problem is the leakage current due to dark resistance of the material or device used. Another is the physical size of such elements. However, their ability to provide galvanic separation makes them a very attractive alternative to conventional (wired) semiconductor elements. This paper gives an overview of available methods and devices before introducing a concept based on the combination of photoresistive and magnetoresistive effects in Gallium Arsenide that are potentially applicable to other semiconductor materials. KW - GaAs KW - High voltage actuators KW - Magnetoresistance KW - Opto-sensors KW - Photoconduction KW - Soft robotics Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-30606 N1 - Corresponding author: Gareth J. Monkman VL - 11 SP - 317 EP - 328 PB - Springer Nature ER - TY - JOUR A1 - Hofrichter, Andreas A1 - Rank, Daniel A1 - Heberl, Michael A1 - Sterner, Michael T1 - Determination of the optimal power ratio between electrolysis and renewable energy to investigate the effects on the hydrogen production costs JF - International Journal of Hydrogen Energy N2 - Green hydrogen via renewable powered electrolysis has a high relevance in decarbonization and supply security. Achieving economically competitive hydrogen production costs is a major challenge in times of an energy price crisis. Our objective is to show the economically optimal installed capacity of electrolysers in relation to wind and solar power so swift and credible statements can be made regarding the system design. The ratio between renewable generation and electrolysis power as well as scaling effects, operating behaviour and development of costs are considered. Hydrogen production costs are calculated for four exemplary real PV and wind sites and different ratios of electrolysis to renewable power for the year 2020. The ideal ratio for PV systems is between 14% and 73% and for wind between 3.3% and 143% for low and high full load hours. The lowest hydrogen production costs are identified at 2.53 €/kg for 50 MW wind power and 72 MW electrolysis power. The results provide plant constructors the possibility to create a cost-optimized design via an optimum ratio of electrolysis to renewable capacity. Therefore, the procedures for planning and dimensioning of selected systems can be drastically simplified. Y1 - 2023 U6 - https://doi.org/10.1016/j.ijhydene.2022.09.263 SN - 0360-3199 N1 - Corresponding author: Michael Heberl N1 - Corrigendum to “Determination of the optimal power ratio between electrolysis and renewable energy to investigate the effects on the hydrogen production costs” [Int J Hydrogen Energy 48 (5) (2023) 1651–1663] - https://doi.org/10.1016/j.ijhydene.2023.03.128 VL - 48 IS - 5 SP - 1651 EP - 1663 PB - Elsevier ER - TY - JOUR A1 - Kinoshita, Keisuke A1 - Delcroix, Marc A1 - Gannot, Sharon A1 - Habets, Emanuel A. P. A1 - Haeb-Umbach, Reinhold A1 - Kellermann, Walter A1 - Leutnant, Volker A1 - Maas, Roland A1 - Nakatani, Tomohiro A1 - Raj, Bhiksha A1 - Sehr, Armin A1 - Yoshioka, Takuya T1 - A summary of the REVERB challenge: state-of-the-art and remaining challenges in reverberant speech processing research JF - Eurasip journal on advances in signal processing N2 - In recent years, substantial progress has been made in the field of reverberant speech signal processing, including both single- and multichannel dereverberation techniques and automatic speech recognition (ASR) techniques that are robust to reverberation. In this paper, we describe the REVERB challenge, which is an evaluation campaign that was designed to evaluate such speech enhancement (SE) and ASR techniques to reveal the state-of-the-art techniques and obtain new insights regarding potential future research directions. Even though most existing benchmark tasks and challenges for distant speech processing focus on the noise robustness issue and sometimes only on a single- channel scenario, a particular novelty of the REVERB challenge is that it is carefully designed to test robustness against reverberation, based on both real, single- channel, and multichannel recordings. This challenge attracted 27 papers, which represent 25 systems specifically designed for SE purposes and 49 systems specifically designed for ASR purposes. This paper describes the problems dealt within the challenge, provides an overview of the submitted systems, and scrutinizes them to clarify what current processing strategies appear effective in reverberant speech processing. KW - Automatic speech recognition KW - Dereverberation KW - Evaluation campaign KW - QUALITY KW - REVERB challenge KW - Reverberation Y1 - 2016 U6 - https://doi.org/10.1186/s13634-016-0306-6 VL - 2016 PB - Springer Nature ER - TY - JOUR A1 - Sterner, Michael A1 - Bauer, Franz T1 - Power-to-X im Kontext der Energiewende und des Klimaschutzes in Deutschland JF - Chemie-Ingenieur-Technik N2 - Um den Einfluss verschiedener Power-to-X-Verfahren auf die Transformation des deutschen Energiesystems und das Erreichen der Klimaschutzziele zu überprüfen, wurde ein sektorübergreifendes Energiesystemmodel entwickelt. Die daraus gewonnenen Ergebnisse zeigen: Für eine erfolgreiche Energiewende ist der Einsatz von Power-to-X in Zukunft unverzichtbar. Vor allem in Bereichen und Sektoren, in denen hohe Energiedichten erforderlich und nur wenig andere Optionen zur Defossilisierung vorhanden sind, werden Power-to-X-Technologien zwingend notwendig. T2 - Power-to-X in Context of Energy Transition and Climate Change Mitigation in Germany KW - Power-to-Gas KW - Climate mitigation KW - Energy system KW - Modeling KW - Power-to-X KW - Klimaschutz KW - Energiewende Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-11669 SN - 0009-286X N1 - Corresponding author: Franz Bauer VL - 92 IS - 1-2 SP - 85 EP - 90 PB - Wiley ER - TY - JOUR A1 - Kravanja, Gaia A1 - Kriegl, Raphael A1 - Hribar, Luka A1 - Glavan, Gašper A1 - Drevenšek-Olenik, Irena A1 - Shamonin (Chamonine), Mikhail A1 - Jezeršek, Matija T1 - Magnetically Actuated Surface Microstructures for Efficient Transport and Tunable Separation of Droplets and Solids JF - Advanced Engineering Materials N2 - Efficient transportation of droplets (∽10 ¹ ̶̶̶̶ 10 ² µl) and small solid objects (∽10 ¹ ̶ 10 ² mm ³ ) have important applications in many fields, such as microfluidics, lab‐on‐a‐chip devices, drug delivery, etc. A novel multifunctional surface consisting of a periodic array of micro‐lamellae from a soft magnetoactive elastomer (MAE) on a plastic substrate is reported for these purposes. The physical origin of the propulsion is the bending of soft magnetic lamellae in non‐uniform magnetic fields, which is also observed in uniform magnetic fields. The magnetoactive surface is fabricated using a facile and rapid method of laser ablation. The propulsion of items is realized using a four‐pole rotating magnet. This results in a cyclic lamellar fringe motion over the micro‐structured surface and brings an advantage of easy reciprocation of transport by rotation reversal. Two modes of object transportation are identified: “pushing” mode for precise control of droplet and solid positioning and “bouncing” mode for heavier solid objects transportation. A water droplet of 5 μl or a glass sphere with a 2.1 mm diameter can be moved at a maximum speed of 60 mm s ⁻¹ . The multifunctionality of the proposed mechatronic platform is demonstrated on the examples of selective solid‐liquid separation and droplet merging. KW - Keywordslaser micromachinings KW - magnetoactive elastomers KW - magnetoresponsivesurfaces KW - object separations KW - object transportations Y1 - 2023 U6 - https://doi.org/10.1002/adem.202301000 SN - 1527-2648 VL - 25 IS - 22 SP - 1 EP - 11 PB - Wiley-VCH ER - TY - JOUR A1 - Monkman, Gareth J. A1 - Sindersberger, Dirk A1 - Prem, Nina A1 - Diermeier, Andreas A1 - Szecsey, Tamara T1 - Dielectric behaviour of magnetic hybrid materials JF - Physical Sciences Reviews N2 - The objectives of this work include the analysis of electrical and magnetic properties of magneto-elastic hybrid materials with the intention of developing new techniques for sensor and actuator applications. This includes the investigation of dielectric properties at both low and high frequencies. The behaviour of capacitors whose dielectrics comprise magnetic hybrid materials is well known. Such interfacial magnetocapacitance can be varied according to magnetic content, magnetic flux density and the relative permittivity of the polymer matrix together with other dielectric content. The basic function of trapping electrical charges in polymers (electrets) is also established technology. However, the combination of magnetoactive polymers and electrets has led to the first electromagnetic device capable of adhering to almost any material, whether magnetically susceptible or not. During the course of this research, in addition to dielectrics, electrically conductive polymers based on (PDMS) matrices were developed in order to vary the electrical properties of the material in a targeted manner. In order to ensure repeatable results, this demanded new fabrication techniques hitherto unavailable. The 3D printing of silicones is far from being a mature technology and much pioneering work was necessary before extending the usual 3 d.o.f. to include orientation about and diffusion of particles in these three axes, thus leading to the concept of 6D printing. In 6D printing, the application of a magnetic field can be used during the curing process to control the particulate distribution and thus the spatial filler particle density as desired. Most of the devices (sensors and actuators) produced by such methods contain levels of carbonyl iron powder (CIP) embedded magnetic filler of up to 70 wt%. Contrary to this, a hitherto neglected research area, namely magnetoactive polymers (MAPs) having significantly lower magnetic particle concentrations (1 to 3 wt% CIP) were also investigated. With filler concentrations lower than 3 wt%, structures are formed which are completely absent at higher filler levels. CIP concentrations in the range of 1wt% demonstrate the formation of toroidal structures. Further development of coherent rings with a compact order results as filler concentrations increase towards 2 wt%. Above 3 wt% the structure eventually disintegrates to the usual random order found in traditional MAP with higher CIP content. Structured samples containing 1%–3 wt% CIP were investigated with the aid of X-ray tomography where solitary ring structures can be observed and eventually the formation of capillary doubles. Over wavelengths ranging from 1 to 25 µm, spectroscopic analysis of thin film MAP samples containing 2 wt% CIP revealed measurable magnetic-field-dependent changes in IR absorption at a wavenumber 2350 (λ = 4.255 µm). This was found to be due to the diamagnetic susceptibility of atmospheric carbon dioxide (CO2). Consequently, the first potential application for sparse matrix MAPs was found. KW - cappillary doublet KW - diamagnetic KW - elastomer dielectric KW - FTIR KW - interfacial magnetocapacitance KW - magnetoactive polymer KW - PDMS KW - toroid Y1 - 2021 U6 - https://doi.org/10.1515/psr-2019-0121 N1 - Corresponding author: Gareth J. Monkman VL - 7 IS - 10 SP - 1169 EP - 1185 PB - de Gruyter ER - TY - JOUR A1 - Kravanja, Gaia A1 - Belyaeva, Inna A. A1 - Hribar, Luka A1 - Drevenšek-Olenik, Irena A1 - Shamonin (Chamonine), Mikhail A1 - Jezeršek, Matija T1 - Laser Micromachining of Magnetoactive Elastomers as Enabling Technology for Magnetoresponsive Surfaces JF - Advanced Materials Technologies N2 - A simple method for structuring of the surface of a magnetoactive elastomer (MAE) on the tens of micrometers scale, which capabilities extend beyond conventional mold-based polymer casting, is reported. The method relies on the ablation of the material by absorption of nanosecond infrared pulses from a commercial laser. It is shown that it is possible to fabricate parallel lamellar structures with a high aspect ratio (up to 6:1) as well as structures with complex scanning trajectories. The method is fast (fabrication time for the 7 × 7 mm2 is about 60 s), and the results are highly reproducible. To illustrate the capabilities of the fabrication method, both orthogonal to the MAE surface and tilted lamellar structures are fabricated. These magnetosensitive lamellae can be easily bent by ±45° using an external magnetic field of about 230 mT. It is demonstrated that this bending allows one to control the sliding angle of water droplets in a great range between a sticky (>90°) and a sliding state (<20°). Perspectives on employing this fabrication technology for magnetosensitive smart surfaces in microfluidic devices and soft robotics are discussed. Y1 - 2021 U6 - https://doi.org/10.1002/admt.202101045 VL - 7 IS - 5 SP - 1 EP - 8 PB - Wiley ER - TY - JOUR A1 - Kravanja, Gaia A1 - Belyaeva, Inna A. A1 - Hribar, Luka A1 - Drevenšek-Olenik, Irena A1 - Jezeršek, Matija A1 - Shamonin (Chamonine), Mikhail T1 - Tunable Drop Splashing on Magnetoactive Elastomers JF - Advanced Materials Interfaces N2 - The significant effect of an external dc magnetic field on the splashing behavior of ethanol drops impacting on the unstructured (flat) surface of soft magnetoactive elastomers (MAEs) is reported. The Weber number corresponding to the transition between the deposition and the splashing regime is reduced by ≈20% in a moderate magnetic field of ≈300 mT. Alongside this effect, a two-fold increase of the initial deceleration of the ejection sheet is observed for the softest sample. The main underlying mechanism for the observed phenomena is believed to be the magnetic-field-induced stiffening of the MAEs. Further possible mechanisms are magnetically induced changes in the surface roughness and magnetic-field-induced plasticity (magnetic shape memory effect). The potential application areas are magnetically regulable wetting and magneto-responsive surfaces for controlling the drop splashing. Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-24504 N1 - Corresponding author: Mikhail Shamonin VL - 8 IS - 11 SP - 1 EP - 7 PB - Wiley ER - TY - JOUR A1 - Prem, Nina A1 - Sindersberger, Dirk A1 - Striegl, Birgit A1 - Böhm, Valter A1 - Monkman, Gareth J. T1 - Shape memory effects using magnetoactive Boron-organo-silicon oxide polymers JF - Macromolecular Chemistry and Physics N2 - Thermomechanical shape memory materials have certain disadvantages when it comes to 3D volumetric reproduction intended for rapid prototyping or robotic prehension. The need to constantly supply energy to counteract elastic retraction forces in order to maintain the required geometry, together with the inability to achieve conformal stability at elevated temperatures, limits the application of thermal shape memory polymers. Form removal also presents problems as most viscoelastic materials do not ensure demolding stability. This work demonstrates how magnetoactive boron−organo−silicon oxide polymers under the influence of an applied magnetic field can be used to achieve energy free sustainable volumetric shape memory effects over extended periods. The rheopectic properties of boron−organo−silicon oxide materials sustain form removal without mold distortion. Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-23205 N1 - Corresponding Author: Gareth J. Monkman VL - 221 IS - 15 SP - 1 EP - 8 PB - Wiley ER - TY - JOUR A1 - Monkman, Gareth J. A1 - Striegl, Birgit A1 - Prem, Nina A1 - Sindersberger, Dirk T1 - Electrical Properties of Magnetoactive Boron‐Organo‐Silicon Oxide Polymers JF - Macromolecular Chemistry and Physics N2 - The electrical properties of rheopectic magnetoactive composites comprising boron-organo-silicon oxide dielectric matrices containing carbonyl iron microparticles are presented for the first time. The increase in interfacial magnetocapacitance is seen to greatly exceed that experienced when using conventional elastomeric matrices such as polydimethylsiloxane. In addition to the increase in capacitance, a simultaneous and sharp decrease in the parallel electrical resistance over several orders of magnitude is also observed. The effects are time dependent but repeatable. Potential applications include magnetically controlled frequency dependent devices, magnetic sensor systems, weighting elements for neural networks, etc. Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-26488 N1 - Corresponding author: Gareth J. Monkman VL - 221 IS - 4 SP - 1 EP - 8 PB - Wiley ER - TY - JOUR A1 - Prem, Nina A1 - Sindersberger, Dirk A1 - Monkman, Gareth J. T1 - Infrared spectral analysis of low concentration magnetoactive polymers JF - Journal of Applied Polymer Science N2 - This work concerns an area of magnetoactive polymer (MAP) research seldom considered. Traditionally only MAP with high concentrations of magnetic filler (typically between 10 and 90 wt%) have been investigated. This article deals with a hitherto neglected aspect of research, namely MAP containing lower magnetic filler concentrations (1 to 3 wt%). This article utilizes a range of spectroscopic analysis methods (Raman and FTIR) and their applicability to MAP characterization at wavelengths ranging from 2.5 to 25 mu m. Particular attention is paid to low carbonyl iron particle (CIP) concentrations in MAP for which the emergence of capillary doublets at a critical 2 wt% concentration is revealed. This results in measurable magnetic field-dependent changes in IR absorption at a wavelength of 4.255 mu m together with a detectable CO2 susceptibility. (c) 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48366. KW - ELASTOMERS KW - magnetism and magnetic properties KW - sensors and actuators KW - spectroscopy Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-25913 SN - 1097-4628 N1 - Corresponding author: Nina Prem VL - 137 IS - 7 SP - 1 EP - 7 PB - Wiley ER - TY - JOUR A1 - Metsch, P. A1 - Schmidt, H. A1 - Sindersberger, Dirk A1 - Kalina, K. A. A1 - Brummund, J. A1 - Auernhammer, Günter A1 - Monkman, Gareth J. A1 - Kästner, Markus T1 - Field-Induced Interactions in Magneto-Active Elastomers BT - A Comparison of Experiments and Simulations JF - Smart Materials and Structures N2 - In this contribution, field-induced interactions of magnetizable particles embedded into a soft elastomer matrix are analyzed with regard to the resulting mechanical deformations. By comparing experiments for two-, three- and four-particle systems with the results of finite element simulations, a fully coupled continuum model for magneto-active elastomers is validated with the help of real data for the first time. The model under consideration permits the investigation of magneto-active elastomers with arbitrary particle distances, shapes and volume fractions as well as magnetic and mechanical properties of the individual constituents. It thus represents a basis for future studies on more complex, realistic systems. Our results show a very good agreement between experiments and numerical simulations—the deformation behavior of all systems is captured by the model qualitatively as well as quantitatively. Within a sensitivity analysis, the influence of the initial particle positions on the systems' response is examined. Furthermore, a comparison of the full three-dimensional model with the often used, simplified two-dimensional approach shows the typical overestimation of resulting interactions in magneto-active elastomers. Y1 - 2020 U6 - https://doi.org/10.1088/1361-665X/ab92dc N1 - Corrigendum: Field-induced interactions in magneto-active elastomers—a comparison of experiments and simulations (2020 Smart Mater. Struct. 29 085026); https://doi.org/10.1088/1361-665X/abb98b VL - 29 IS - 8 SP - 1 EP - 10 PB - IOPscience ER - TY - JOUR A1 - Schmidt, Henrik A1 - Straub, Benedikt B. A1 - Sindersberger, Dirk A1 - Bröckel, Ulrich A1 - Monkman, Gareth J. A1 - Auernhammer, Günter T1 - Collision and separation of nickel particles embedded in a Poly dimethylsiloxan matrix under a rotating magnetic field: A strong magneto active function JF - Colloid and Polymer Science N2 - In order to function as soft actuators, depending on their field of use, magnetorheological elastomers (MREs) must fulfill certain criteria. To name just a few, these can include rapid response to external magnetic fields, mechanical durability, mechanical strength, and/or large deformation. Of particular interest are MREs which produce macroscopic deformation for small external magnetic field variations. This work demonstrates how this can be achieved by just a small change in magnetic field orientation. To achieve this, (super)paramagnetic nickel particles of size ≈ 160 μm were embedded in a non-magnetic polydimethylsiloxan (PDMS) (661–1301 Pa) and their displacement in a stepwise rotated magnetic field (170 mT) recorded using a video microscope. Changes in particle aggregation resulting from very small variations in magnetic field orientation led to the observation of a new strongly magneto-active effect. This configuration is characterized by an interparticle distance in relation to the angle difference between magnetic field and particle axis. This causes a strong matrix deformation which in turn demonstrates hysteresis on relaxation. It is shown that the occurrence strongly depends on the particle size, particle distance, and stiffness of the matrix. Choosing the correct parameter combination, the state can be suppressed and the particle-matrix system demonstrates no displacement or hysteresis. In addition, evidences of non-negligible higher order magnetization effects are experimentally ascertained which is qualitatively in agreement with similar, already theoretically described, particle systems. Even at larger particle geometries, the new strongly magneto-active configuration is preserved and could create macroscopic deformation changes. Y1 - 2021 U6 - https://doi.org/10.1007/s00396-020-04784-4 VL - 299 SP - 955 EP - 967 PB - Springer ER - TY - JOUR A1 - Straus, Izidor A1 - Kokot, Gašper A1 - Kravanja, Gaia A1 - Hribar, Luka A1 - Kriegl, Raphael A1 - Shamonin (Chamonine), Mikhail A1 - Jezeršek, Matija A1 - Drevenšek-Olenik, Irena T1 - Dynamically tunable lamellar surface structures from magnetoactive elastomers driven by a uniform magnetic field JF - Soft Matter N2 - Stimuli responsive materials are key ingredients for any application that requires dynamically tunable or on-demand responses. In this work we report experimental and theoretical investigation of magnetic-field driven modifications of soft-magnetic elastomers whose surface was processed by laser ablation into lamellar microstructures that can be manipulated by a uniform magnetic field. We present a minimal hybrid model that elucidates the associated deflection process of the lamellae and explains the lamellar structure frustration in terms of dipolar magnetic forces arising from the neighbouring lamellae. We experimentally determine the magnitude of the deflection as a function of magnetic flux density and explore the dynamic response of lamellae to fast changes in a magnetic field. A relationship between the deflection of lamellae and modifications of the optical reflectance of the lamellar structures is resolved. KW - Intelligente Materialien Y1 - 2023 U6 - https://doi.org/10.1039/D3SM00012E VL - Vol. 19 SP - 3357 EP - 3365 PB - Royal Society of Chemistry ER - TY - CHAP A1 - Kravanja, Gaia A1 - Belyaeva, Inna A. A1 - Hribar, Luka A1 - Drevenšek-Olenik, Irena A1 - Shamonin (Chamonine), Mikhail A1 - Jezeršek, Matija T1 - Adaptive Magneto-Responsive Surfaces Fabricated by Laser-Based Microstructuring T2 - Proceedings of the ASME 2022 Conference on Smart Materials, Adaptive Structures and Intelligent Systems (SMASIS 2022): September 12-14, 2022, Dearborn, Michigan N2 - Adaptive surface microstructures are used extensively in nature to control various surface properties such as wettability, adhesion, self-cleaning, drag reduction, etc. Regulation of these properties can be achieved with the appropriate employment of a multitude of smart materials, whose characteristics/response can be controlled by noncontact stimuli, e.g., light, heat, or magnetic field. One of the very promising magneto-regulable smart materials are magnetoactive elastomers (MAEs). They are comprised of a compliant polymer matrix with embedded micrometer-sized ferromagnetic particles. The particles interact with each other and a magnetic field. This results in remarkable tunability of the physical properties of MAEs. This paper reports a fast, resilient, and tailored method for direct surface micromachining of MAEs that enables micro-structuring without mechanical contact between the tool and the material, bypassing the usual constraints of conventional fabrication methods. It is shown that it is possible to fabricate a large variety of different microstructure geometries whose precision is limited predominantly by the size of magnetic particles. Lamellar structures with a high aspect ratio (up to 6:1) oriented either perpendicularly to the surface, can be strongly bent by applying magnetic fields in the range of 0–250 mT. KW - adaptive surfaces KW - magnetoactive elastomers KW - magneto-responsive microstructures KW - laser microstructuring Y1 - 2022 SN - 978-0-7918-8627-4 U6 - https://doi.org/10.1115/SMASIS2022-90742 PB - ASME ER - TY - CHAP A1 - Fuhrmann, Thomas T1 - Course Preparation Time Optimization System for Improved Didactic Outcome T2 - 2022 20th International Conference on Information Technology Based Higher Education and Training (ITHET), 07-09 November 2022, Antalya, Turkey N2 - Due to the various demands for lecturers, there is only a limited time to prepare lectures and lab courses. Therefore, it is necessary to invest the time target-oriented for optimal student learning success. A theoretic model is developed to structure course preparation work regarding scientific content, didactic preparation, and course presentation. Model parameters have to be chosen for each course depending on topic complexity, the lecturer’s prior knowledge, and the already available preparation from the prior semesters. With these parameters, a course preparation model for a complete semester is developed. Analytic models for different optimization strategies are introduced according to the overall goal of the lecturer. Numerical optimization is done to find the appropriate course preparation times to reach an optimal course preparation for high student learning success. It is seen that due to the different optimization strategies, the preparation time results vary and no single truth is given. But this optimization system gives hints on how to invest preparation time target-oriented for high student learning success. KW - Higher education KW - Engineering education KW - Course preparation KW - Curriculum development KW - Optimization Y1 - 2022 SN - 978-1-6654-8908-9 U6 - https://doi.org/10.1109/ITHET56107.2022.10031642 PB - IEEE ER - TY - CHAP A1 - Boody, F. P. A1 - Bickel, Peter A1 - Kempf, J. A1 - Monkman, Gareth J. A1 - Höpfl, R. A1 - Hora, H. A1 - Laska, L. A1 - Krasa, J. A1 - Pfeifer, M. A1 - Rohlena, K. A1 - Juha, L. A1 - Wolowski, J. A1 - Badziak, J. A1 - Parys, P. A1 - Ryc, L. A1 - Worya, E. A1 - Szydlowski, A. A1 - Torrisi, L. A1 - Gammino S., A1 - Mezzasalma, A. T1 - Flexible laser ion sources for surface modification T2 - Plasma Production by Laser Ablation, PPLA 2003 : Messina and Catania, Italy, 18-19 September 2003 Y1 - 2003 PB - World Scientific Publishing CY - Singapore ER - TY - CHAP A1 - Weiss, Nils A1 - Renner, Sebastian A1 - Mottok, Jürgen A1 - Matoušek, Václav T1 - Automated Threat Evaluation of Automotive Diagnostic Protocols T2 - ESCAR USA, 2021, Virtual N2 - Diagnostic protocols in automotive systems can offer a huge attack surface with devastating impacts if vulnerabilities are present. This paper shows the application of active automata learning techniques for reverse engineering system state machines of automotive systems. The developed black-box testing strategy is based on diagnostic protocol communication. Through this approach, it is possible to automatically investigate a highly increased attack surface. Based on a new metric, introduced in this paper, we are able to rate the possible attack surface of an entire vehicle or a single Electronic Control Unit (ECU). A novel attack surface metric allows comparisons of different ECUs from different Original Equipment Manufacturers (OEMs), even between different diagnostic protocols. Additionally, we demonstrate the analysis capabilities of our graph-based model to evaluate an ECUs possible attack surface over a lifetime. KW - Automotive Diagnostic Protocols KW - Security Metrics KW - Automated Network Scan Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-29882 ER - TY - CHAP A1 - Frauenschläger, Tobias A1 - Dentgen, Manuel A1 - Mottok, Jürgen T1 - Systemarchitektur eines Sicherheitsmoduls im Energiesektor T2 - Tagungsband 2. Symposium Elektronik und Systemintegration ESI 2020: "Intelligente Systeme und ihre Komponenten: Forschung und industrielle Anwendung" N2 - Aufgrund der immer weiter anwachsenden Vernetzung der Stromnetze wird die Kommunikation zwischen der Leitstelle des Energieversorgers und den Infrastrukturkomponenten innerhalb eines Umspannwerks immer bedeutsamer. Dabei werden sowohl Steuerbefehle als auch Daten für Überwachungsfunktionen übertragen. In den aktuellen Netzwerkarchitekturen findet diese Kommunikation ohne eine kryptografische Absicherung statt, was einen Angriffspunkt für gezielte Attacken und damit eine potenzielle Gefährdung der Energieversorgung darstellt. Um solchen Angriffen in Zukunft entgegenzuwirken, wird das ES³M-Sicherheitsmodul entwickelt. Dieses soll in das Netzwerk zwischen den beiden Kommunikationspartnern eingesetzt werden und so den Datenverkehr absichern. Mithilfe einer Bedrohungsanalyse wurden Anforderungen abgeleitet, die neben kryptografischen Maßnahmen auch Themen wie funktionale Sicherheit und Langlebigkeit umfassen. Um diese zu erfüllen, wurde eine spezielle Systemarchitektur auf Basis einer Aufgabenteilung entworfen. Diese Architektur und korrespondierende Designentscheidungen werden präsentiert. Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:860-opus4-2092 N1 - Die Konferenzveröffentlichung erschien im Band "Fachbeiträge 2. Symposium Elektronik und Systemintegration ESI 2020" mit dem Titel „Intelligente Systeme und ihre Komponenten: Forschung und industrielle Anwendung“. Die Fachtagung, geplant für den 01. April 2020 an der Hochschule Landshut, wurde aufgrund der Corona-Pandemie abgesagt, die eingereichten Fachbeiträge im Band veröffentlicht. Hrsg.: Artem Ivanov, Marc Bicker und Peter Patzelt. Hochschule Landshut, 2020, ISBN 978-3-9818439-4-1 SP - 29 EP - 38 CY - Landshut ER - TY - JOUR A1 - Grabinger, Lisa A1 - Hauser, Florian A1 - Mottok, Jürgen T1 - On the perception of graph layouts JF - Journal of Software: Evolution and Process N2 - In the field of software engineering, graph-based models are used for a variety of applications. Usually, the layout of those graphs is determined at the discretion of the user. This article empirically investigates whether different layouts affect the comprehensibility or popularity of a graph and whether one can predict the perception of certain aspects in the graph using basic graphical laws from psychology (i.e., Gestalt principles). Data on three distinct layouts of one causal graph is collected from 29 subjects using eye tracking and a print questionnaire. The evaluation of the collected data suggests that the layout of a graph does matter and that the Gestalt principles are a valuable tool for assessing partial aspects of a layout. KW - causal graphs KW - eye tracking KW - gestalt principles KW - graph layouts KW - modeling languages Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-62973 N1 - Corresponding author: Lisa Grabinger PB - Wiley ER - TY - CHAP A1 - Felis, Simeon A1 - Mottok, Jürgen A1 - Bauer, B. A1 - Kohlert, Dieter A1 - Jantz, D. A1 - Laumer, M. T1 - FBI3 – Fehlereinspeisung auf Hardware-Ebene T2 - 3. Landshuter Symposium Mikrosystemtechnik, Tagungsband, 13. und 14. März 2012, Hochschule Landshut Y1 - 2012 SP - 119 EP - 127 ER - TY - CHAP A1 - Osinski, Lukas A1 - Mottok, Jürgen T1 - A Multicore Fault Tolerance Approach Based on Coded Processing T2 - Embedded Real-Time Software and Systems Conference (ERST²), Jan 2018, Toulouse/France N2 - Development trends for computing platforms moved from increasing the frequency of a single processor to increasing the parallelism with multiple cores on the same die. Multiple cores have strong potential to support cost-efficient fault tolerance due to their inherent spatial redundancy. This work makes a step towards software-only fault tolerance in the presence of permanent and transient hardware faults. Our approach utilizes software-based spatial triple modular redundancy and coded processing on a shared memory multi-core controller. We evaluate our approach on an Infineon AURIX TriBoard TC277 and provide experimental evidence for error resistance by fault injection campaigns with an iSystem iC5000 On-chip Analyzer. Y1 - 2018 UR - https://hal.archives-ouvertes.fr/hal-02156233 ER - TY - CHAP A1 - Raab, Peter A1 - Krämer, Stefan A1 - Mottok, Jürgen A1 - Meier, Hans A1 - Racek, Stanislav T1 - Safe software processing by concurrent execution in a real-time operating system T2 - 16th International Conference on Applied Electronics (AE 2011), 2011, Pilsen, Czech Republic N2 - The requirements for safety-related software systems increases rapidly. To detect arbitrary hardware faults, there are applicable coding mechanism, that add redundancy to the software. In this way it is possible to replace conventional multi-channel hardware and so reduce costs. Arithmetic codes are one possibility of coded processing and are used in this approach. A further approach to increase fault tolerance is the multiple execution of certain critical parts of software. This kind of time redundancy is easily realized by the parallel processing in an operating system. Faults in the program flow can be monitored. No special compilers, that insert additional generated code into the existing program, are required. The usage of multi-core processors would further increase the performance of such multi-channel software systems. In this paper we present the approach of program flow monitoring combined with coded processing, which is encapsulated in a library of coded data types. The program flow monitoring is indirectly realized by means of an operating system. Y1 - 2011 SP - 315 EP - 319 ER - TY - GEN ED - Mottok, Jürgen ED - Ziemann, Olaf T1 - 2nd Applied Research Conference 2012 (ARC 2012), 25./26. June 2012, Nuremberg Y1 - 2012 SN - 978-3-8440-1093-0 PB - Shaker Verlag CY - Aachen ER - TY - CHAP A1 - Lalo, Erjola A1 - Sailer, Andreas A1 - Mottok, Jürgen A1 - Siemers, Christian T1 - Overhead-Aware Schedule Synthesis for Logical Execution Time (LET) in Automotive Systems T2 - 2022 IEEE 35th International System-on-Chip Conference (SOCC): 05-08 September 2022, Belfast, United Kingdom N2 - The Logical Execution Time (LET) has recently been integrated in multi-core automotive systems to ensure timing and dataflow determinism. Although buffering mechanisms are introduced to incorporate LET semantics, they do not guarantee that tasks are executed within their LET frames. In fact, LET and buffering semantics are violated if scheduling is not designed to execute all tasks within their LET frames and in a specific order. In this paper, we describe a scheduling synthesis technique for Fixed-Priority Scheduling (FPS) to achieve resource-efficient execution of LET systems. The proposed approach considers LET semantics, scheduling overheads, and delays caused by operating system operations and provides the possibility to optimize the schedule with respect to aspects like scheduling overheads. Our performance and feasibility evaluation shows that the proposed algorithm provides results in a reasonable amount of time for models of complex industrial applications. Thus, the integration of the proposed algorithm into an automated process is of high benefit to accelerate the development of vehicle applications. Y1 - 2022 SN - 978-1-6654-5985-3 U6 - https://doi.org/10.1109/SOCC56010.2022.9908103 SP - 1 EP - 6 PB - IEEE ER - TY - CHAP A1 - Mottok, Jürgen T1 - Porting the microsoft .net micro framework onto an embedded operating system T2 - 2nd Applied Research Conference 2012 (ARC 2012) 25./26. June 2012, Nuremberg Y1 - 2012 SP - 26 EP - 30 ER - TY - CHAP A1 - Jahn, Sabrina A1 - Kaul, Nicolas A1 - Mottok, Jürgen T1 - Using or Misusing? Introducing Misuse Cases in a Software Engineering Course for Undergraduate Engineering Students T2 - ITiCSE '22 : Proceedings of the 27th ACM Conference on on Innovation and Technology in Computer Science Education, Vol 1: July 8 - 13, 2022, Dublin Ireland N2 - Today's cyberphysical systems are increasingly prone to misuse. To secure existing and future software systems, introducing concepts of IT-Security and Secure Software Engineering (SecSE) in Software Engineering (SE) courses is essential for academic education of future software engineers. This is not only important for computer science students, but also for engineering students studying topics of computing and SE. However, only little research exists on integrating these topics into traditional SE courses, especially for engineering students in non-computer science majors. To narrow this gap, this paper contributes with the design and evaluation of an exercise on modeling misuse cases alongside use cases, based on the inductive teaching method problem-based learning (PBL). The exercise is part of an educational design research investigating which learning content and teaching methods are suitable for integrating IT-Security and SecSE topics into traditional SE education of engineering students to convey factual knowledge as well as raise awareness and interest for both topics during software development. We present the integration of the exercise design into a traditional SE course for engineering students and its evaluation to examine its suitability. We evaluated the exercise design regarding the suitability of the design components, the learning content of misuse cases and the intended learning goals as well as its impact on students' motivation, and their interest in IT-security. The paper then presents indications on the feasibility and success of the exercise design for teaching misuse cases to engineering students and sparking their interest in IT-Security. KW - educational design research KW - mis-use case KW - problem-based learning KW - inductive teaching KW - engineering students KW - higher education KW - secure software engineering KW - IT-Security Y1 - 2022 U6 - https://doi.org/10.1145/3502718.3524823 SP - 491 EP - 497 PB - Association for Computing Machinery CY - New York, NY ER - TY - CHAP A1 - Mucha, Matthias A1 - Mottok, Jürgen A1 - Krämer, Stefan T1 - Estimation of Worst Case Response Time Boundaries in Multi-Core Real-Time Systems T2 - 2017 International Conference on Applied Electronics (AE), 5-6 Sept. 2017, Pilsen N2 - We address a novel probabilistic approach to estimate the Worst Case Response Time boundaries of tasks. Multi-core real-time systems process tasks in parallel on two or more cores. Tasks in our contribution may preempt other tasks, block tasks with semaphores to access global shared resources, or migrate to another core. The depicted task behavior is random. The shape of collected response times of a task within a processing time is multimodal. Extreme Value approaches need unimodal response time distributions to estimate the Worst Case Response Time of tasks. The new proposed method derives a set of three task set shapes from the source task set. It is used to minimize the uncertainty of random task behavior by maximizing the coverage of possible Worst Case Response Times. The case study evaluates the new proposed estimation method by the use of dynamically generated random tasks with varying task properties. Y1 - 2017 SN - 978-80-261-0641-8 U6 - https://doi.org/10.23919/ae.2017.8053598 SN - 1803-7232 SP - 1 EP - 6 PB - IEEE ER - TY - GEN A1 - Renner, Sebastian A1 - Pozzobon, Enrico A1 - Mottok, Jürgen T1 - 3rd Round Ciphers Evaluation on Microcontrollers T2 - Lightweight Cryptography Workshop (virtual): May 9-11 2022 Y1 - 2022 UR - https://www.nist.gov/video/day-1-part-2-lightweight-cryptography-workshop-2022 PB - National Institute of Standards and Technology (NIST) CY - Gaithersburg ER - TY - CHAP A1 - Fritz, Florian A1 - Schmid, Michael A1 - Mottok, Jürgen ED - Brinkmann, André T1 - Accelerating Real-Time Applications with Predictable Work-Stealing T2 - Architecture of computing systems - ARCS 2020: 33rd international conference, Aachen, Germany, May 25-28, 2020, proceedings N2 - Modern compute architectures often consist of multiple CPU cores to achieve their performance, as physical properties put a limit on the execution speed of a single processor. This trend is also visible in the embedded and real-time domain, where programmers are forced to parallelize their software to keep deadlines. Additionally, embedded systems rely increasingly on modular applications, that can easily be adapted to different system loads and hardware configurations. To parallelize applications under these dynamic conditions, often dispatching frameworks like Threading Building Blocks (TBB) are used in the desktop and server segment. More recently, Embedded Multicore Building Blocks (EMB2) was developed as a task-based programming solution designed with the constraints of embedded systems in mind. In this paper, we discuss how task-based programming fits such systems by analyzing scheduler implementation variants, with a focus on classic work-stealing and the libraries TBB and EMB2. Based on the state of the art we introduce a novel resource-trading concept that allows static memory allocation in a work-stealing runtime holding strict space and time bounds. We conduct benchmarks between an early prototype of the concept, TBB and EMB2, showing that resource-trading does not introduce additional runtime overheads, while unfortunately also not improving on execution time variances. KW - Real-time KW - Parallel programming KW - Work-stealing Y1 - 2020 U6 - https://doi.org/10.1007/978-3-030-52794-5_18 SP - 241 EP - 255 ER - TY - CHAP A1 - Frauenschläger, Tobias A1 - Renner, Sebastian A1 - Mottok, Jürgen T1 - Security Improvements by Separating the Cryptographic Protocol from the Network Stack onto a Multi-MCU Architecture T2 - Architecture of Computing Systems - ARCS 2020: 33rd international conference, Aachen, Germany, May 25-28, 2020, proceedings N2 - The number of IoT devices in SCADA and ICS systems is rising quickly, especially in the domain of critical infrastructures. But these kinds of systems are performing mission critical tasks like controlling devices in industrial facilities or substations in the smart grid. Therefore, they are subject to a lot of regulatory standards. Yet, to provide remote access over the internet, special architectures are developed to integrate a network interface into these devices without inferring with the actual functionality. However, these architectures either lack security measures against cyber-attacks or do not offer the necessary performance for time-critical communication interfaces. To solve that, an architecture consisting of three units is introduced in this paper to provide a network interface with extensive security measures and a high performance. The main feature is the isolation of the cryptographic functionality onto an additional MCU. After proposing the basic concept, the paper presents many implementation details. Based on the current state of implementation, a concept validation of the realized architecture is described. KW - Cyber-security KW - Functional safety KW - Network security KW - Industrial Internet of Things KW - Industrial Control System KW - Supervisory Control and Data Acquisition System Multi microcontroller setup Dos prevention Critical infrastructures KW - Multi microcontroller setup Dos prevention Critical infrastructures KW - Dos prevention KW - Critical infrastructures Y1 - 2020 U6 - https://doi.org/10.1007/978-3-030-52794-5_14 SP - 185 EP - 199 PB - Springer International Publishing ER - TY - CHAP A1 - Gschossmann, Andreas A1 - Jobst, Simon A1 - Mottok, Jürgen A1 - Bierl, Rudolf T1 - A Measure of Confidence of Artificial Neural Network Classifiers T2 - ARCS Workshop 2019; 32nd International Conference on Architecture of Computing Systems, 20-21 May 2019, Copenhagen, Denmark N2 - Confidence in results of an Artificial Neural Networks (ANNs) is increased by preferring to reject data, that is not trustful, instead of risking a misclassification. For this purpose a model is proposed that is able to recognize data, which differs significantly from the training data, during inference. The proposed model observes all activations of the hidden layers, as well as input and output layers of an ANN in a grey-box view. To make ANNs more robust in safety critical applications, this model can be used to reject flawed data, that is suspected to decrease the accuracy of the model. If this information is logged during inference, it can be used to improve the model, by training it specifically with the missing information. An experiment on the MNIST dataset is conducted and its results are discussed. Y1 - 2019 UR - https://ieeexplore.ieee.org/document/8836211 SP - 153 EP - 157 PB - VDE-Verlag CY - Berlin ER - TY - CHAP A1 - Weiss, Nils A1 - Renner, Sebastian A1 - Mottok, Jürgen A1 - Matoušek, Václav T1 - Transport Layer Scanning for Attack Surface Detection in Vehicular Networks T2 - CSCS '20: Computer Science in Cars Symposium N2 - In the beginning of every security analysis or penetration test of a system, information about the target has to be gathered. On IT-Systems a port scan is usually performed as a first step of an investigation. Since the communication protocols differ in automotive systems, generic port scanning tools can’t be used for a security analysis of CANs. More complex protocols have a higher likelihood of implementation errors and bugs. On CAN networks, such payloads are transferred through International Standard Transport Protocol (ISO-TP) communication. We designed a new methodology to identify ISO-TP endpoints in automotive networks. Every of these endpoints can provide exploitable application layer protocols and therefor has to be considered during penetration testing and security analysis. We contribute a new scan approach for the automated evaluation of possible attack surfaces in automotive CAN networks which has a higher coverage and multiple advantages than state of the art approaches. KW - automotive networks KW - network scan KW - attack surface detection KW - automation Y1 - 2020 U6 - https://doi.org/10.1145/3385958.3430476 IS - 7 SP - 1 EP - 8 CY - Feldkirchen ER - TY - CHAP A1 - Jahn, Sabrina A1 - Mottok, Jürgen T1 - Work in Progress: Towards an Academic Secure Software Engineering Curriculum for Engineers T2 - 2020 IEEE Global Engineering Education Conference (EDUCON): 27-30 April 2020, Porto, Portugal N2 - In the age of the Internet of Things, it is becoming increasingly important to integrate knowledge about the development of secure systems (Secure Software Engineering) into academic teaching. However, teaching IT Security and Secure Software Engineering to non-computer scientists is rare. Therefore, we focus our research on the integration of IT Security into software engineering education of non-computer scientists, particularly electrical engineers, by means of inductive teaching- and learning-arrangements. After collecting students' preconceptions of IT Security and Secure Software Engineering in prior work, this paper now contributes with a first mapping of these preconceptions with corresponding learning content as well as suitable inductive teaching methods to be able to create new lecture and exercise units and improve academic learning and teaching in both areas. Y1 - 2020 U6 - https://doi.org/10.1109/EDUCON45650.2020.9125210 SP - 1713 EP - 1717 ER - TY - CHAP A1 - Hauser, Florian A1 - Schreistetter, Stefan A1 - Reuter, Rebecca A1 - Mottok, Jürgen A1 - Gruber, Hans A1 - Holmqvist, Kenneth A1 - Schorr, Nick T1 - Code reviews in C++: Preliminary results from an eye tracking study T2 - ETRA '20 Short Papers: ACM Symposium on Eye Tracking Research and ApplicationsJune 2020 N2 - Code reviews are an essential part of quality assurance in modern software projects. But despite their great importance, they are still carried out in a way that relies on human skills and decisions. During the last decade, there have been several publications on code reviews using eye tracking as a method, but only a few studies have focused on the performance differences between experts and novices. To get a deeper understanding of these differences, the following experiment was developed: This study surveys expertise-related differences in experts’, advanced programmers’, and novices’ eye movements during the review of eight short C++ code examples, including correct and erroneous codes. A sample of 35 participants (21 novices, 14 advanced and expert programmers) were recruited. A Tobii Spectrum 600 was used for the data collection. Measures included participants’ eye movements during the code review, demographic background data, and cued retrospective verbal comments on replays of their own eye movement recordings. Preliminary results give proof for experience-related differences between participants. Advanced and expert programmers performed significantly better in case of error detection and the eye tracking data implies a more efficient reviewing strategy. Y1 - 2020 SN - ISBN 9781450371346 U6 - https://doi.org/10.1145/3379156.3391980 SP - 1 EP - 5 ER - TY - CHAP A1 - Schmid, Michael A1 - Fritz, Florian A1 - Mottok, Jürgen T1 - Parallel Programming in Real-Time Systems T2 - Architecture of computing systems - ARCS 2019, 32nd international conference, Copenhagen, Denmark, May 20-21, 2019, proceedings N2 - The enormous amounts of data modern real-time systems have to process lead to expensive, long-lasting calculations. In order to manage those computations in a timely manner, parallel task models have gained a lot of popularity lately. However, parallel programming can be very cumbersome and verbose. Other computationally intensive sectors have dealt with parallel computing for decades and have accumulated their experience in the development of parallel frameworks. Examples of well known parallel runtime systems are OpenMP, Intel Threading Building Blocks (TBB) and Microsoft Parallel Pattern Library (PPL). These runtime systems allow developers to enhance parallelism in their applications in a straightforward fashion. However, those parallel frameworks and the patternbased interfaces they provide might not be easily applicable in real-time systems. In this paper, we investigate the use of parallel programming frameworks in time-critical systems. On that account, we discuss considerations for the design of real-time applications that make use of such parallel runtime systems. Furthermore, we evaluate three library-based frameworks from different computing sectors, namely Intel Threading Building Blocks, Embedded Multicore Building Blocks (EMBB) and High Performance ParalleX (HPX), by conducting benchmarks of various parallel algorithms on an embedded multicore architecture. Y1 - 2019 UR - https://ieeexplore.ieee.org/abstract/document/8836206 PB - VDE-Verlag CY - Berlin ER - TY - CHAP A1 - Mottok, Jürgen A1 - Schiller, Frank A1 - Völkl, Thomas A1 - Zeitler, Thomas T1 - A concept for a safe realization of a state machine in embedded automotive applications T2 - Computer safety, reliability, and security, 26th International Conference, SAFECOMP 2007, Nuremberg, Germany, September 18-21, 2007; proceedings N2 - Currently, both fail safe and fail operational architectures are based on hardware redundancy in automotive embedded systems. In contrast to this approach, safety is either a result of diverse software channels or of one channel of specifically coded software within the framework of Safely Embedded Software. Product costs are reduced and flexibility is increased. The overall concept is inspired by the well-known Vital Coded Processor approach. Since Mealy state machines are frequently used in embedded automotive systems, application software with a general Mealy state machine is realized differently with Safely Embedded Software starting from the high level programming language C with corresponding measurements. KW - Safely KW - Embedded Software KW - Safe State Machine KW - Diverse Instructions KW - Safety Code Weaving KW - Safety Supervisor Y1 - 2007 U6 - https://doi.org/10.1007/978-3-540-75101-4_2 SP - 283 EP - 288 ER - TY - GEN A1 - Renner, Sebastian A1 - Pozzobon, Enrico A1 - Mottok, Jürgen T1 - Current and Future Efforts in Benchmarking NIST LWC Ciphers T2 - 4th Lightweight Cryptography Workshop 2020 at NIST, Gaithersburg, USA Y1 - 2020 UR - https://csrc.nist.gov/CSRC/media/Presentations/efforts-in-benchmarking-lwc-ciphers/images-media/session-4-renner-current-future-benchmarking.pdf ER - TY - JOUR A1 - Hummel, M. A1 - Mottok, Jürgen A1 - Egen, R. A1 - Schiller, Frank A1 - Mattes, T. A1 - Blum, M. A1 - Druckstein, F. T1 - Generische Safety-Architektur für Kfz-Software JF - Spektrum, das Magazin der Hochschule Regensburg Y1 - 2007 CY - Regensburg ER - TY - JOUR A1 - Schiller, Frank A1 - Mottok, Jürgen A1 - Blum, M. A1 - Duckstein, F. A1 - Egen, R. A1 - Hummel, M. A1 - Mattes, T. T1 - Generische Safety-Architektur für KFZ-Software JF - Hanser automotive Y1 - 2006 SP - 52 EP - 54 ER - TY - CHAP A1 - Deubzer, Michael A1 - Mottok, Jürgen A1 - Flug, Christian A1 - Zeitler, Thomas T1 - Profiling Performance Analyse von Embedded Real-Time System Architekturen T2 - Embedded Software Engineering Kongress, Tagungsband ; 8. bis 10. Dezember 2008, Sindelfingen Y1 - 2008 SP - 155 EP - 167 ER - TY - JOUR A1 - Federrath, H. A1 - Mottok, Jürgen A1 - Plößl, K. A1 - Völkl, Thomas T1 - Automotive safety and security JF - Jahresrückblick 2007 des Bayerischen IT-Sicherheitsclusters Y1 - 2007 ER - TY - JOUR A1 - Hobelsberger, Martin A1 - Mottok, Jürgen A1 - Kuntz, Stefan T1 - Architekturmodellierung: Vergleich von EAST ADL und SAE AADL JF - Hanser Automotive Y1 - 2007 IS - 7-8 SP - 43 EP - 47 ER - TY - CHAP A1 - Bärwald, Andreas A1 - Hauff, Harald A1 - Mottok, Jürgen T1 - Qualification and certification of development tools for safety-critical applications T2 - Proceedings of Dependability@SIEMENS Conference N2 - This paper presents an overview on qualification and certification of tools used in the phases of the safety lifecycle for safety-critical applications, either for development or for verification and validation. Software development tools are widely used in the development of safety-critical software systems. More verification and validation procedures will be automated by software tools to reduce time consuming manual testing. The impact of software tools on functional safety is discussed. Based on normative regulations like IEC 61508 and ISO DIS 26262 different approaches for tool qualification and certification are presented. Y1 - 2009 ER - TY - JOUR A1 - Hartig, Wolfgang A1 - Habermann, Albert A1 - Mottok, Jürgen T1 - Mehr Qualität durch modellbasiertes Testen JF - Elektronik automotive 3 Y1 - 2009 UR - https://www.elektroniknet.de/automotive/software-tools/mehr-qualitaet-durch-modellbasiertes-testen.1370.html SP - 32 EP - 35 ER - TY - CHAP A1 - Steindl, Michael A1 - Mottok, Jürgen A1 - Meier, Hans A1 - Schiller, Frank A1 - Früchtl, M. T1 - Diskussion des Einsatzes von Safely Embedded Software in FPGA-Architekturen T2 - Proceedings of the 2nd Embedded Software Engineering Congress, 8. bis 10. Dezember 2009, Sindelfingen Y1 - 2009 SP - 655 EP - 661 ER - TY - CHAP A1 - Krämer, Stefan A1 - Mottok, Jürgen A1 - Meier, Hans T1 - Modifikation des Taskzustandsmodells des LLREF-Schedulers auf einem Dual-Core-Prozess T2 - Proceedings of the 2nd Embedded Software Engineering Congress, 8. bis 10. Dezember 2009, Sindelfingen Y1 - 2009 SP - 628 EP - 636 ER - TY - CHAP A1 - Schorer, Michael A1 - Kuntz, Stefan A1 - Mottok, Jürgen T1 - Beschreibung eines kooperativen Tasksystems mit OSEK-konformen Scheduler durch Petri Netze T2 - Proceedings of the 2nd Embedded Software Engineering Congress, 8. bis 10. Dezember 2009, Sindelfingen Y1 - 2009 SP - 637 EP - 644 ER - TY - CHAP A1 - Steindl, Michael A1 - Mottok, Jürgen A1 - Meier, Hans A1 - Schiller, Frank A1 - Früchtl, M. T1 - Migration of SES to FPGA Based Architectural Concepts T2 - Proceedings of the Workshop 'Safely embedded software' Y1 - 2009 ER - TY - JOUR A1 - Hartig, Wolfgang A1 - Habermann, Albert A1 - Mottok, Jürgen T1 - Model-based testing for better quality JF - Vector, Technicle Article Y1 - 2009 ER - TY - JOUR A1 - Raab, Peter A1 - Mottok, Jürgen A1 - Meier, Hans T1 - OSEK-RTOS für Jedermann (Teil 2) JF - Embedded Software Engineering Report Y1 - 2009 VL - 53 SP - 10 EP - 12 ER - TY - JOUR A1 - Mottok, Jürgen T1 - Safely embedded software JF - Embedded Software Engineering Report Y1 - 2009 VL - 53 SP - 10 EP - 11 ER - TY - JOUR A1 - Deubzer, Michael A1 - Mottok, Jürgen A1 - Margull, Ulrich A1 - Niemetz, Michael A1 - Wirrer, Gerhard T1 - Efficient Scheduling of Reliable Automotive Multi-core Systems with PD² by Weakening ERfair Task System Requirements JF - Automotive Safety and Security N2 - Partly Proportionate fair (Partly-Pfair) scheduling, which allows task migration at runtime and assigns each task processing time with regard to its weight, makes it possible to build highly efficient embedded multi-core systems. Due to its non-work-conserving behavior, which might leave the CPU idle even when tasks are ready to execute, tasks finish only shortly before their deadlines are reached. Benefits are lower task jitter, but additional workload, e.g. through interrupts, can lead to deadline violations. In this paper we present a work-conserving extension of Partly-Pfair scheduling, called PERfair scheduling and the algorithm P-ERfair-PD2 which applies Pfair modifications used for Partly-Pfair on the concept of ERfairness and PD2 policies. With a simulation based schedulability examination we show for multiple time base (MTB) task sets that P-ERfair- PD2 has the same performance as Partly-Pfair-PD2. Additionally, we show that P-ERfair- PD2 has a much higher robustness against perturbations, and therefore it is well suited for embedded domains, especially for the Automotive domain. Y1 - 2010 UR - https://www.researchgate.net/publication/287883010_Efficient_scheduling_of_reliable_automotive_multi-core_systems_with_pd2_by_weakening_erfair_tasksystem_requirements SP - 53 EP - 67 ER - TY - CHAP A1 - Schorer, Michael A1 - Kuntz, Stefan A1 - Mottok, Jürgen T1 - Verification of Behavioral Compatibility in the Virtual Integration Methodology T2 - 8th IEEE Workshop on Intelligent Solutions in Embedded Systems,Heraklion, Greece, July 2010 N2 - The advantages of component-based systems include reuse of generic components as well as adaption through variants. However, they bare a high risk of containing incompatibilities between components, due to the lack of control over the integration-relevant aspects of their components. Current development processes are able to detect incompatibilities between components only at very late stages of system development. The Virtual Integration methodology is an approach to detect and to solve compatibility issues during early stages of system design. The methodology supports developers with a set of measures to reduce the risk of incompatibilities to a minimum at each abstraction layer of their system architecture. Realtime requirements of embedded systems make it necessary to support the methodology with a formal model, which can describe dynamic properties of these systems. In our approach, we use interface automata because they offer a lightweight formalism to describe the behavior of components and to verify their compatibility based on these descriptions. In a feasibility study we show, to which extend interface automata are adequate for the foresaid purpose in the automotive application field. Y1 - 2010 U6 - https://doi.org/10.1109/WISES.2010.5548424 SP - 35 EP - 42 ER - TY - JOUR A1 - Deubzer, Michael A1 - Schiller, Frank A1 - Mottok, Jürgen A1 - Niemetz, Michael A1 - Margull, Ulrich T1 - Effizientes Multicore-Scheduling in Eingebetteten Systemen – Teil 2: Ein simulationsbasierter Ansatz zum Vergleich von Scheduling-Algorithmen JF - atp - Automatisierungstechnische Praxis N2 - Eingebettete Systeme unterliegen neben den funktionalen Anforderungen besonders nichtfunktionalen Qualitätsanforderungen wie Effizienz, Zuverlässigkeit und Echtzeitfähigkeit. Mit steigendem Bedarf an Rechenkapazität können bisherige Konzepte zur Leistungssteigerung von Singlecore-Systemen jedoch nicht mehr eingesetzt werden - der Umstieg auf Multicore-Systeme wird erforderlich. Im zweiten Teil dieser Arbeit wird ein simulationsbasierter Ansatz zum Vergleich von Multicore-Scheduling-Algorithmen vorgestellt, mit dem Algorithmen für Multicore-Systeme mit voller Migration und dynamischer Task-Priorität untersucht werden. Wir erweitern diesen Ansatz um ein Verfahren zur Untersuchung einer Tasksetmenge mit stochastisch beschriebenen Eigenschaften und vergleichen ihn mit den im Teil 1 beschriebenen Algorithmen BinPacking-EDF und P-ERfair-PD² für eine Gruppe von Automotive Powertrain Systemen. Y1 - 2010 VL - 52 IS - 10 ER - TY - CHAP A1 - Deubzer, Michael A1 - Margull, Ulrich A1 - Mottok, Jürgen A1 - Niemetz, Michael A1 - Wirrer, Gerhard T1 - Partly Proportionate Fair Multiprocessor Scheduling of Heterogeneous Task Systems T2 - 5th Embedded Real Time Software and Systems Conference, May 2010 N2 - Proportionate fair (Pfair) scheduling, which allows task migration at runtime and assigns each task processing time with regard to its weight, is one of the most efficient group of SMP multiprocessor scheduling algorithms known up to now. Drawbacks are tight requirements to the task system, namely the restriction to periodic task systems with synchronized task activation, quantized task execution time, and implicit task deadline. Most likely, a typical embedded real-time system does not fulfill these requirements. In this paper we address violations of these requirements. For heterogeneous task systems, we define the multiple time base (MTB) task system, which is a less pessimistic model than sporadic task systems and is used for automotive systems. We apply the concept of Pfair scheduling to MTB task systems, called partly proportionate fair (Partly-Pfair) scheduling. The restrictions on MTB task systems required for Partly-Pfair ness are weaker than restrictions on periodic task systems required for Pfair ness. In a simulation based study we examined the performance of Partly-Pfair-PD and found it capable to schedule feasible MTB task sets causing a load of up to 100% of the system capacity. Y1 - 2010 ER - TY - CHAP A1 - Bärwald, Andreas A1 - Hauff, Harald A1 - Mottok, Jürgen T1 - Qualification and Certification of Development Tools for Safety-Critical Applications T2 - Automotive Safety & Security N2 - This paper presents an overview on qualification and certification of tools used in the phases of the safety lifecycle for safety-critical applications, either for development or for verification and validation. Software development tools are widely used in the development of safety-critical software systems. More verification and validation procedures will be automated by software tools to reduce time consuming manual testing. The impact of software tools on functional safety is discussed. Based on normative regulations like IEC 61508 and ISO DIS 26262 different approaches for tool qualification and certification are presented. Y1 - 2010 UR - https://www.researchgate.net/publication/289001902_Qualification_and_certification_of_development_tools_for_safety-critical_applications SP - 135 EP - 149 ER - TY - CHAP A1 - Steindl, Michael A1 - Mottok, Jürgen A1 - Meier, Hans T1 - SES-based Framework for Fault-tolerant Systems T2 - 8th IEEE Workshop on Intelligent Solutions in Embedded Systems, Heraklion, Greece, July 2010 N2 - Embedded real-time systems are often used in harsh environments, for example engine control systems in automotive vehicles. In such ECUs (Engine Control Unit) faults can lead to serious accidents. In this paper we propose a safety embedded architecture based on coded processing. This framework only needs two channels to provide fault tolerance and allows the detection and identification of permanent and transient faults. Once a fault is detected by an observer unit the SES guard makes it visible and initiates a suitable failure reaction. Y1 - 2010 U6 - https://doi.org/10.1109/WISES.2010.5548427 SP - 12 EP - 16 ER - TY - CHAP A1 - Stappert, Friedhelm A1 - Jonsson, Jan A1 - Mottok, Jürgen A1 - Johansson, Rolf T1 - A Design Framework for End-to-End Timing Constrained Automotive T2 - 5th Embedded Real Time Software and Systems Conference (ERTS2 2010), May 2010, Toulouse, France Y1 - 2010 UR - https://hal.archives-ouvertes.fr/hal-02264378 ER - TY - GEN A1 - Bärwald, Andreas A1 - Mottok, Jürgen T1 - Zertifizierung von Werkzeugen und Werkzeugketten T2 - Software im Automobil, Stuttgart, 04./05. Mai 2010 Y1 - 2010 UR - https://de.slideshare.net/AndreasBaerwald/zertifizierung-von-werkzeugen-und-werkzeugketten ER - TY - JOUR A1 - Bärwald, Andreas A1 - Hauff, Harald A1 - Mottok, Jürgen T1 - Certification of safety relevant systems – Benefits of using pre-certified components JF - Automotive Safety and Security Y1 - 2010 ER - TY - CHAP A1 - Lalo, Erjola A1 - Deubzer, Michael A1 - Schmidhuber, Stefan A1 - Oklapi, Erna A1 - Mottok, Jürgen T1 - Task Priority Optimization in Real-Time Multi-Core Embedded Systems T2 - 4. Landshuter Symposium Mikrosystemtechnik, Mikrosystemtechnik als Schlüsseltechnologie der Systemintegration, Tagungsband zum Symposium 12./13. März 2014, Hochschule Landshut N2 - The shift from single-core to multi-core processors in real-time embedded systems leads to communication based effects on timing such as inter-core communication delays and blocking times. Moreover, the complexity of the scheduling problem increases when multi-core processors are used. In priority-based-scheduling, a fixed priority assignment is used in order to enable predictable behavior of the system. Predictability means that the system has to be analyzable which allows the detection of problems coming from scheduling decisions. For fixed priority scheduling in multi-core real-time embedded systems, a proper task priority assignment has to be done in a way that the system has minimal effects on timing. In this paper, we present an approach for finding near-optimal solutions for task priority assignment and the preemption/cooperation problem. A genetic algorithm is hereby used to create priority assignment solutions. A timing simulator is used for evaluation of each solution regarding real-time properties, memory consumption and communication overhead. In a case study we demonstrate that the proposed approach performs better than well known and single-core optimal heuristics for relatively complex systems. Y1 - 2014 SN - 978-3-9812696-5-9 SP - 96 EP - 109 CY - Landshut ER - TY - CHAP A1 - Alfranseder, Martin A1 - Deubzer, Michael A1 - Justus, Benjamin A1 - Mottok, Jürgen A1 - Siemers, Christian T1 - An Efficient Spin-Lock Based Multi-Core Resource Sharing Protocol T2 - 33rd IEEE International Performance, Computing, and Communications Conference (IPCCC), Austin (TX), USA, 5-7 December 2014 N2 - We present in this paper a new lock-based resource sharing protocol PWLP (Preemptable Waiting Locking Protocol) for embedded multi-core processors. It is based on the busy-wait model and works with non-preemptive critical sections while task may be preempted by tasks with a higher priority when waiting for resources. Our protocol can be applied in partitioned as well as global scheduling scenarios, in which task-fix, job-fix or dynamically assigned priorities may be used. Furthermore, the PWLP permits nested requests to shared resources. Finally, we present a case study based on event-based simulations in which the FMLP (Flexible Multiprocessor Locking Protocol) and the proposed PWLP are compared. Y1 - 2014 U6 - https://doi.org/10.1109/PCCC.2014.7017090 ER - TY - CHAP A1 - Alfranseder, Martin A1 - Krapf, Tobias A1 - Mader, Ralph A1 - Niemetz, Michael A1 - Mottok, Jürgen A1 - Siemers, Christian T1 - An Efficient Partitioning Strategy for Runnables in Weakly Dependent Tasks on Embedded Multi-Core Systems T2 - Embedded real-time software and systems (ERTS² 2014), Feb 2014, Toulouse, France N2 - With multi-core controllers entering the area of automotive control ECUs, strategies for parallelizing the control- algorithms come into focus. This paper deals with a special part of automotive powertrain software, called state transitions. Since dependencies between runnables executed there are weak, the transitions provide a good basis for parallelization. We present a strategy of how to distribute efficiently the execution of runnables to different cores while taking care of inner and outer dependencies. The strategy is accompanied by two case studies demonstrating the performance of the concept. The first one is carried out to find the most efficient strategies of parallelize state transitions based on randomly generated, simulated state transitions. In the second one, the developed partitioning strategies are applied to a real software project for an automotive powertrain system. Y1 - 2014 ER - TY - CHAP A1 - Krämer, Stefan A1 - Raab, Peter A1 - Mottok, Jürgen A1 - Racek, Stanislav T1 - Comparison of Enhanced Markov Models and Discrete Event Simulation T2 - 17th Euromicro Conference on Digital System Design (DSD), 27-29 August 2014, Verona, Italy N2 - In this paper we present simulation and model based approaches for evaluating and validating the temporal and safety relevant properties of software intensive safety-critical real-time embedded systems. A high level reliability model of a safe task execution is described by a continuous-time Markov process, enhanced by the modeling of execution times. It is shown that the behavior - regarding real-time and safety metrics - of this theoretical model can be transferred into an abstract system timing model, which then can be analyzed by a discrete event simulation approach. The verification of the discrete event simulation by Markov models offers the possibility of a holistic approach for reliability analysis combined with schedulability analysis of complex safety-critical multicore real-time systems by the discrete event simulation. Y1 - 2014 U6 - https://doi.org/10.1109/DSD.2014.42 SP - 591 EP - 598 ER - TY - CHAP A1 - Helm, C. A1 - Deubzer, Michael A1 - Mottok, Jürgen ED - Ivanov, Artem ED - Bicker, Marc ED - Patzelt, Peter T1 - Analyse der Echtzeiteigenschaften von Multicore Speicherarchitekturen in Eingebetteten Systemen mittels einer konfigurierbaren Simulationssoftware T2 - 4. Landshuter Symposium Mikrosystemtechnik : Mikrosystemtechnik als Schlüsseltechnologie der Systemintegration, Tagungsband zum Symposium 12./13. März 2014, Hochschule Landshut Y1 - 2014 SN - 978-3-9812696-5-9 SP - 109 EP - 117 CY - Landshut ER - TY - CHAP A1 - Lalo, Erjola A1 - Schmidhuber, Stefan A1 - Deubzer, Michael A1 - Mottok, Jürgen T1 - Extended Task Priority and Preemptability Optimization in Real-Time Multi-Core Embedded Systems T2 - 4th Applied Research Conference, 5th July 2014, Ingolstadt Y1 - 2014 SN - 978-3-8440-2875-1 SP - 90 EP - 95 CY - Ingolstadt ER - TY - CHAP A1 - Mottok, Jürgen A1 - Krämer, Stefan A1 - Deubzer, Michael A1 - Hobelsberger, Martin A1 - Martin, Felix T1 - Hardware Based Tracing of Embedded Multi-Core Systems T2 - 4th Applied Research Conference, 5th July 2014, Ingolstadt Y1 - 2014 SN - 978-3-8440-2875-1 ER - TY - CHAP A1 - Thiel, P. A1 - Hackl, Magnus A1 - Mottok, Jürgen T1 - Designing efficient Node.js applications – Approaching useful patterns T2 - 4th Applied Research Conference, 5th July 2014, Ingolstadt Y1 - 2014 SN - 978-3-8440-2875-1 SP - 40 EP - 46 PB - Shaker CY - Aachen ER - TY - CHAP A1 - Hackl, Magnus A1 - Thiel, Patrik A1 - Mottok, Jürgen T1 - Not Only SQL – a comparison to traditional RDBMS T2 - 4th Applied Research Conference (ARC 2014), 5th July 2014, Ingolstadt Y1 - 2014 SN - 978-3-8440-2875-1 PB - Shaker CY - Aachen ER - TY - CHAP A1 - Braun, Jürgen A1 - Mottok, Jürgen T1 - Fail-Safe and Fail-Operational Systems safeguarded with Coded Processing T2 - 2013 IEEE EUROCON - International Conference on Computer as a Tool, Zagreb, Croatia, July 1-4, 2013 N2 - Safety has the highest priority because it helps contribute to customer confidence and thereby ensures further growth of the new markets, like electromobility. Therefore in series production redundant hardware concepts like dual core microcontrollers running in lock-step-mode are used to reach for example ASIL D safety requirements given from the ISO 26262. Coded processing is capable of reducing redundancy in hardware by adding diverse redundancy in software, e.g. by specific coding of data and instructions. A system with two coded processing channels is considered. Both channels are active. When one channel fails, the service can be continued with the other channel. It is imaginable that the two channels with implemented coded processing are running with time redundancy on a single core or on a multi core system where for example different ASIL levels are partitioned on different cores. In this paper a redundancy concept based on coded processing will be taken into account. The improvement of the Mean Time To Failure by safeguarding the system with coded processing will be computed for fail-safe as well as for fail-operational systems. The use of the coded processing approach in safeguarding failsafe systems is proved. KW - fail-safe KW - fail-operational KW - fault-tolerant KW - failure probability KW - coded processing KW - Safely Embedded Software KW - SES KW - safety measure KW - ISO 26262 KW - electromobility KW - Mean Time To Failure KW - MTTF KW - reliability KW - diversity Y1 - 2013 SN - 978-1-4673-2231-7 U6 - https://doi.org/10.1109/EUROCON.2013.6625234 SP - 1878 EP - 1885 ER - TY - CHAP A1 - Sailer, Andreas A1 - Schmidhuber, Stefan A1 - Deubzer, Michael A1 - Alfranseder, Martin A1 - Mucha, Matthias A1 - Mottok, Jürgen T1 - Optimizing the task allocation step for multi-core processors within autosar T2 - 2013 International Conference on Applied Electronics, IEEE, Pilsen, Czech Republic N2 - We present a model-based optimization approach for the task allocation problem in embedded multi-core systems. The information therefore is obtained from a system description in AUTOSAR and runtime measurements of the runnables in hardware traces. Based on this an initial software partitioning of runnables to tasks is created. We then use a genetic algorithm to create and evaluate solutions to the task allocation problem. Each solution is hereby evaluated using a discrete event-based simulation, which allows the evaluation with regard to real-time properties, resource consumption and data-communication overhead. The significance of our approach is then shown in a case-study. There, we optimize the task allocation of an embedded system, whose complexity is comparable to that of an actual system, on a multi-core processor. Finally, the results of the optimization are transferred to an ECU Configuration Description to enable further development in compliance with the AUTOSAR methodology. KW - AUTOSAR KW - Multi-Objective Optimization KW - Multi-Core KW - Goodness-of-fit KW - Task Allocation Y1 - 2013 UR - https://ieeexplore.ieee.org/document/6636524 ER - TY - CHAP A1 - Alfranseder, Martin A1 - Mucha, Matthias A1 - Schmidhuber, Stefan A1 - Sailer, Andreas A1 - Niemetz, Michael A1 - Mottok, Jürgen T1 - A modified synchronization model for dead-lock free concurrent execution of strongly interacting task sets in embedded systems T2 - 2013 International Conference on Applied Electronics (AE 2013), IEEE, 10-12 September 2013, Pilsen, Czech Republic N2 - Global scheduling algorithms are very promising for application in embedded real-time systems using multi-core controllers. In this paper we want to make a first step forward to apply such scheduling methods on real existing systems. Especially a new resource model is necessary to avoid deadlocks, as this goal can not be achieved by using the standard OSEK Priority Ceiling Protocol when shared global resources are in use. We also introduce the new metric mean Normalized Blocking Time in order to be able to compare locking mechanisms according to the timing effects of their blocking behavior. Finally we give a simulative application example of the new metric by the use of two different kinds of semaphore models and an example task set typical for existing embedded real-time systems in the automotive powertrain environment. Y1 - 2013 VL - 18 SP - 13 EP - 18 ER - TY - CHAP A1 - Raab, Peter A1 - Krämer, Stefan A1 - Mottok, Jürgen T1 - Error Model and the Reliability of Arithmetic Operations T2 - 2013 IEEE EUROCON - International Conference on Computer as a Tool, Zagreb, Croatia, July 1-4, 2013 N2 - Error detecting and correcting codes are widely used in data transmission, storage systems and also for data processing. In logical circuits like arithmetic operations, arbitrary faults can cause errors in the result. However in safety critical applications, it is important to avoid those errors which would lead to system failures. Several approaches are known to protect the result of operations during software processing. In the same way like transmission systems, coded processing uses codes for fault detection. But in contrast to transmission systems, there is no adequate channel model available which makes it possible to evaluate the residue error probability of an arithmetic operation in an analytical way. This paper tries to close the gap of arithmetic error models by the development of a model for an ordinary addition in a computer system. Thus, the reliability of an addition's result can be analytically evaluated. KW - addition KW - channel model KW - coded processing KW - fault simulation KW - Markov model KW - residue error probability Y1 - 2013 U6 - https://doi.org/10.1109/EUROCON.2013.6625047 SP - 630 EP - 637 ER - TY - CHAP A1 - Raab, Peter A1 - Racek, Stanislav A1 - Krämer, Stefan A1 - Mottok, Jürgen T1 - Data Flow Analysis of Software Executed by Unreliable Hardware T2 - 16th Euromicro Conference on Digital System Design, Los Alamitos, CA, USA N2 - The data flow is a crucial part of software execution in recent applications. It depends on the concrete implementation of the realized algorithm and it influences the correctness of a result in case of hardware faults during the calculation. In logical circuits, like arithmetic operations in a processor system, arbitrary faults become a more tremendous aspect in future. With modern manufacturing processes, the probability of such faults will increase and the result of a software's data flow will be more vulnerable. This paper shows a principle evaluation method for the reliability of a software's data flow with arbitrary soft errors also with the concept of fault compensation. This evaluation is discussed by means of a simple example based on an addition. KW - data flow KW - error probability KW - fault compensation KW - reliability analysis KW - software-implemented-hardwarefault-tolerance (SIHFT) Y1 - 2013 U6 - https://doi.org/10.1109/DSD.2013.35 SP - 243 EP - 249 ER - TY - GEN A1 - Alfranseder, Martin A1 - Schmidhuber, Stefan A1 - Mucha, Matthias A1 - Sailer, Andreas A1 - Mottok, Jürgen T1 - How to improve the reactiveness and efficiency of embedded multicore systems by use of probabilistic simulation and optimization techniques: A case study BT - Invited Poster Session T2 - Advanced Research Workshop: Improving Disaster Resilience and Mitigation - New Means and Tools, Trends, Iasi Y1 - 2013 ER - TY - CHAP A1 - Sailer, Andreas A1 - Schmidhuber, Stefan A1 - Deubzer, Michael A1 - Mottok, Jürgen T1 - Amalthea – Plattform für kontinuierliche, modellbasierte Entwicklung T2 - Tagungsband, 6th Embedded Software Engineering, Kongress 2013, 2. bis 6. Dezember 2013, Sindelfingen Y1 - 2013 SP - 538 EP - 544 ER - TY - CHAP A1 - Alfranseder, Martin A1 - Krapf, Tobias A1 - Mottok, Jürgen A1 - Siemers, Christian T1 - Synchronisationsverfahren in embedded Multicoresystemen T2 - Tagungsband, 6th Embedded Software Engineering, Kongress 2013, 2. bis 6. Dezembern 2013, Sindelfingen Y1 - 2013 PB - Vogel Business Media CY - Würzburg ER - TY - RPRT A1 - Pfaller, M. A1 - Mottok, Jürgen T1 - Developing the e-learning class ‘practical training in c’ Y1 - 2013 ER - TY - CHAP A1 - Braun, Jürgen A1 - Mottok, Jürgen A1 - Miedl, Christian A1 - Geyer, Dirk A1 - Minas, Mark T1 - Increasing the reliability of single and multicore systems with software rejuvenation and coded processing T2 - Automotive Safety & Security 2012, Sicherheit und Zuverlässigkeit für automobile Informationstechnik, 14.-15. Nov. 2012, Karlsruhe N2 - The safety of electric vehicles has the highest priority because it helps contribute to customer confidence and thereby ensures further growth of the electromobility market. Therefore in series production redundant hardware concepts like dual core microcontrollers running in lock-step-mode are used to reach ASIL D safety requirements given from the ISO 26262. Coded processing is capable of reducing redundancy in hardware by adding diverse redundancy in software, e.g. by specific coding of data and instructions. A system with two coded processing channels is considered. One channel is active and one is in cold standby. When the active channel fails, the service is switched from the active channel to the standby channel. It is imaginable that the two channels with implemented coded processing are running with time redundancy on a single core or on a multi core system where for example different ASIL levels are partitioned on different cores. In this paper a redundant concept based on coded processing and software rejuvenation will be taken into account. Y1 - 2012 UR - https://dl.gi.de/handle/20.500.12116/17555 SP - 163 EP - 178 ER - TY - CHAP A1 - Schumm, Michael A1 - Joseph, Saskia A1 - Schroll-Decker, Irmgard A1 - Niemetz, Michael A1 - Mottok, Jürgen T1 - Required competences in software engineering – pair programming as an instrument for facilitating life-long learning T2 - 15th International Conference on Interactive Collaborative Learning and 41st International Conference on Engineering Pedagogy, Villach N2 - The professional requirements in software engineering have become highly volatile due to the complexities of project development and rapid and innovative changes occurring in the field. Therefore, the development of inter-personal and social competences has gained central importance in the training of software developers. The following text will present a concept allowing to acquire competences by using Pair Programming as an instrument. Moreover, arrangements for learning and teaching will be presented facilitating the acquisition of these competences. By approaching the issue of competence acquisition on a technical as well as on an educational and social level, lifelong learning is facilitated and supported. Y1 - 2012 U6 - https://doi.org/10.1109/ICL.2012.6402229 ER - TY - CHAP A1 - Krämer, Stefan A1 - Raab, Peter A1 - Mottok, Jürgen A1 - Racek, Stanislav T1 - Reliability analysis of real-time scheduling by means of stochastic simulation T2 - 2012 International Conference on Applied Electronics (AE 2012), Pilsen, Czech Republic, 5 - 7 September 2012 N2 - We present a simulation-based approach to reliability analysis combined with a schedulability analysis of software intensive embedded real-time systems. In such a system not only does the software execution have to be hardened against soft errors, e.g., by means of coded processing or diverse execution, but also the real-time requirements have still to be met in the presence of such error to guarantee a safe operation of the system. For that reason, the influence regarding the real-time characteristics of a given sporadic error with a certain error rate is analyzed by means of a Monte Carlo simulation. Different safety design patterns are introduced and compared. Furthermore, the impact on the schedulability of an embedded system is discussed. Y1 - 2012 SP - 151 EP - 156 ER - TY - CHAP A1 - Raab, Peter A1 - Racek, Stanislav A1 - Krämer, Stefan A1 - Mottok, Jürgen T1 - Reliability of Task Execution during Safe Software Processing T2 - 15th Euromicro Conference on Digital System Design, Cesme, Turkey N2 - This paper presents the reliability evaluation of task execution during safe software processing. The standard method of duplication in a safety-critical application can also be applied for tasks in a software system. But in addition to this, there is also the possibility for coded task processing to increase the reliability and availability of software. The presented analysis covers the reliability analysis of a single, a duplicated and a coded task by the technique of continuous time Markov processes. Markov processes are often used for the reliability evaluation of safety-critical systems. We introduce a method to describe the execution time of tasks by means of enhanced Markov models and their solution by numerical methods. KW - reliability analysis KW - continuous-time Markov process KW - error probability KW - Erlang-distribution Y1 - 2012 U6 - https://doi.org/10.1109/DSD.2012.110 SP - 84 EP - 89 ER - TY - CHAP A1 - Braun, Jürgen A1 - Mottok, Jürgen A1 - Miedl, Christian A1 - Geyer, Dirk A1 - Minas, Mark T1 - Capability of single hardware channel for automotive safety applications according to ISO 26262 T2 - 2012 International Conference on Applied Electronics (AE 2012), Pilsen, Czech Republic, 5 - 7 September 2012 Y1 - 2012 SN - 978-80-261-0038-6 SP - 41 EP - 45 ER - TY - CHAP A1 - Schumm, Michael A1 - Joseph, Saskia A1 - Mottok, Jürgen A1 - Niemetz, Michael A1 - Schroll-Decker, Irmgard T1 - Lernarrangements im software engineering und deren evaluation – neue konzepte für hochschule und lebenslanges Lernen T2 - Tagungsband 5th Embedded Software Engineering Kongress, 3. bis 7. Dezember 2012, Sindelfingen Y1 - 2012 ER - TY - CHAP A1 - Krämer, Stefan A1 - Raab, Peter A1 - Mottok, Jürgen T1 - Simulationsbasierte Reliability-Analyse – Einflüsse von zufälligen Fehlern auf das Echtzeit-Scheduling T2 - Tagungsband 5th Embedded Software Engineering Kongress, 3. bis 7. Dezember 2012, Sindelfingen Y1 - 2012 SP - 613 EP - 622 ER - TY - CHAP A1 - Alfranseder, Martin A1 - Mottok, Jürgen T1 - Kommunikationsmechanismen für sicherheitskritische multi-core Echtzeit-Systeme T2 - 5th Automotive Summerschool, Regensburg, September 2012 Y1 - 2012 ER - TY - CHAP A1 - Mottok, Jürgen T1 - Embedded trends T2 - Technologietag 2012, am 28. März, München Y1 - 2012 ER - TY - CHAP A1 - Braun, Jürgen A1 - Mottok, Jürgen T1 - The Myths of Coded Processing T2 - IEEE International Conference on High Performance Computing and Communications (HPCC-ICESS-CSS 2015), 24-26 Aug. 2015, New York, USA N2 - Safety of embedded systems has the highest priority because it helps contribute to customer confidence and thereby ensures growth of the new markets, like electromobility. In series production fail-safe systems as well as fault-tolerant systems are realized with redundant hardware concepts like dual core microcontrollers running in lock-step-mode to reach highest safety requirements given by standards, like ISO 26262 or IEC 61508. In contrast to the hardware redundancy approach, there are also approaches available with information-, time-and/or software-redundancy since several years. One of them is known as coded processing or AN-codes. Coded processing is capable of reducing redundancy in hardware by adding diverse redundancy in software. But the breakthrough of coded processing never took place. One reason for this seem to be the myths which are widely propagated on this subject and the hereby associated uncertainties. In this paper some myths are busted, like the usage of prime numbers as transformation factor A, the myth that greater transformation factors are better or the myth about the residual error probability defined as 1/A. Some of them have been propagated since 1989. The aim of this paper is to provide more clarity and understanding for this technique, perhaps to pave the way for further functional safety concepts based on coded processing approaches. KW - Redundancy KW - Hamming distance KW - Safety KW - Encoding KW - Error probability Y1 - 2015 U6 - https://doi.org/10.1109/HPCC-CSS-ICESS.2015.24 SP - 1637 EP - 1644 ER - TY - JOUR A1 - Raab, Peter A1 - Krämer, Stefan A1 - Mottok, Jürgen T1 - Reliability of data processing and fault compensation in unreliable arithmetic processors, Microprocessors and Microsystems JF - Microprocessors and Microsystems N2 - In logical circuits, like arithmetic operations in a processor system, arbitrary faults become a more tremendous aspect in future. Modern manufacturing processes lead to less reliability and higher vulnerability of software execution to soft-errors. The correctness of certain results is important especially for safety–critical applications whose reliability depends on the fault-free execution of each single instruction and the dependencies between them. The more complex a software is the more unreliable the outcome is. But, there is a contrary effect. If the probability for multiple faults increases, there is also the chance that two faults compensate each other and the result is correct again. This paper presents the basic ideas for such a reliability evaluation of a software's data flow with arbitrary soft-errors and the effect of fault compensation. Further, this evaluation provides a possibility to compare different implementations of a data flow with respect to the reliability. This is shown by the comparison of two different error codes as alternatives for coded data processing. Y1 - 2016 U6 - https://doi.org/10.1016/j.micpro.2015.07.014 VL - 40 IS - Februar SP - 102 EP - 112 PB - Elsevier ER - TY - CHAP A1 - Krämer, Stefan A1 - Mottok, Jürgen A1 - Racek, Stanislav T1 - Proportionate fair based multicore scheduling for fault tolerant multicore real-time systems T2 - International Conference on Electrical and Information Technologies (ICEIT), 25-27 March 2015, Marakesch, Morocco N2 - In this paper we present a scheduling approach for safety critical, fault tolerant, multicore real-time embedded systems. For this kind of systems, not only the correctness of a computed result but also the strict adherence to timing requirements of computation is essential to avoid any kind of damage. To react to unpredictable, arbitrary hardware faults suitable error detection mechanisms have to be applied. The caused error itself and the detection and correction have great impact on the system's timing behavior. To still keep the real-time requirements, the used scheduling algorithm has to ensure maximum flexibility to disturbances of the timing. The group of Proportionate Fair (Pfairness) multicore scheduling algorithms has been proven to create an optimal schedule in polynomial time. The contribution of this paper is a Pfair-based algorithm that uses tight coupling between the error detection mechanisms and the scheduler of the real-time operating system to establish a loop-back connection. KW - Multicore processing KW - Time factors KW - Safety KW - Schedules KW - Scheduling algorithms KW - Real-time systems Y1 - 2015 U6 - https://doi.org/10.1109/EITech.2015.7162952 SP - 88 EP - 93 ER - TY - CHAP A1 - Soska, Alexander A1 - Schroll-Decker, Irmgard A1 - Mottok, Jürgen T1 - Implementation of Practical Exercises in Software Engineering Education to Improve the Acquirement of Functional and Non-Functional Competences T2 - 2014 International Conference on Interactive Collaborative Learning (ICL), 3-6 Dec. 2014, Dubai, UAE N2 - Software Engineering is a very volatile profession that requires a variety of theoretical as well as practical skills. In addition to expertise technical knowledge, graduates have to have a variety of social, methodical and personal competences. The acquirement of these non-functional competences are getting more and more important for a successful software engineer. To fulfill these requirements, it is necessarily important to prepare future professionals already during their college course of education. This paper presents exercises for a software engineering lecture with the goal to strengthen the students' practical experiences and to support the development of their non-functional competences. The developed exercises impart technical knowledge and encourage the students to improve their self-organized and lifelong learning. Thereby they are facing practical issues in all steps of the software engineering process while working on an inter semester project. KW - software engineering education KW - project-based learning KW - software engineering exercises KW - competences Y1 - 2014 U6 - https://doi.org/10.1109/ICL.2014.7017795 ER - TY - CHAP A1 - Mucha, Matthias A1 - Mottok, Jürgen A1 - Deubzer, Michael T1 - Probabilistic worst case response time estimation for multi-core real-time systems T2 - 2015 4th Mediterranean Conference on Embedded Computing (MECO), 14-18 June 2015, Budva, Montenegro N2 - Traditional methods rely on Static Timing Analysis techniques to compute the Worst Case Response Time for tasks in real-time systems. Multi-Core real-time systems are faced up with concurrent task executions, semaphore accesses, and task migrations where it may be difficult to obtain the worst case upper bound. A new three staged probabilistic estimation concept is presented. Worst Case Response Times are estimated for tasksets which consist of tasks with multiple time bases. The concept involves data generation with sample classification and sample size equalization, model fit and Worst Case Response Time estimation on the basis of extreme value distribution models. A Generalized Pareto Distribution model fit method which includes threshold detection and parameter estimation is also presented. Sample classification in combination with the new Generalized Pareto Distribution model fit method allows to estimate Worst Case Response Times with low pessimism ranges compared to estimation methods that uses the Generalized Pareto or the Gumbel max distribution without sample classification. Y1 - 2015 SP - 31 EP - 36 ER - TY - CHAP A1 - Studt, Reimer A1 - Winterfeldt, Götz A1 - Mottok, Jürgen T1 - Measuring software engineering competencies T2 - 2015 IEEE Global Engineering Education Conference (EDUCON), 18-20 March 2015, Tallinn, Estonia N2 - Measuring competencies may serve as a feedback mechanism as well as a judgment device for a lecturer. As measuring every competency from a catalogue of competencies is not very viable, the to-be-measured competencies are grouped in competency profiles. Further, assessment practices are shown and applied to a course in a study program. A discussion of useful practices concludes this contribution. Y1 - 2015 U6 - https://doi.org/10.1109/EDUCON.2015.7096081 ER - TY - CHAP A1 - Steindl, Michael A1 - Mottok, Jürgen T1 - Considering Schedule Requirements of Software Integration in Component based Embedded System T2 - International Conference on Applied Electronics, 2012, Pilsen, Czech Republic Y1 - 2012 ER - TY - CHAP A1 - Mottok, Jürgen T1 - Verbundprojekt EVELIN T2 - HDS.Forum Lernkulturen Y1 - 2012 ER - TY - CHAP A1 - Mottok, Jürgen T1 - Entdeckendes Lernen T2 - HDS.Forum Lernkulturen Y1 - 2012 ER - TY - CHAP A1 - Soska, Alexander A1 - Mottok, Jürgen A1 - Wolff, Christian T1 - An experimental card game for software testing: Development, design and evaluation of a physical card game to deepen the knowledge of students in academic software testing education T2 - IEEE Global Engineering Education Conference (EDUCON), 10-13 April 2016, Abu Dhabi, UAE N2 - Teaching software testing is a challenging task. Especially if you want to impart more in-depth and practical knowledge to the students. Therefore, most lectures still teach in a classic lecture format despite the fact that this way of instruction is in any case the optimal way of instruction for today's requirements anymore. In this paper we present our implementation of an active learning method to deepen the knowledge in academic software test education. We describe a card game for advanced learning that promotes students' collaboration and knowledge exchange in a playful and competitive manner. The design of the game is based on constructive and cooperative theories. A subsequent evaluation shows that the use of this card game for teaching software testing is a suitable method. KW - software testing KW - playful learning KW - game-based learning KW - card game Y1 - 2016 U6 - https://doi.org/10.1109/EDUCON.2016.7474609 SP - 576 EP - 584 ER - TY - CHAP A1 - Sailer, Andreas A1 - Deubzer, Michael A1 - Lüttgen, Gerald A1 - Mottok, Jürgen T1 - CoreTAna: A Trace Analyzer for Reverse Engineering Real-Time Software T2 - IEEE 23rd International Conference on Software Analysis, Evolution, and Reengineering (SANER), March 14 to March 18 2016, Suita, Osaka, Japan N2 - With the availability of the AUTOSAR standard, model-driven methodologies are becoming established in theautomotive domain. However, the process of creating models ofexisting system components is often difficult and time consuming, especially when legacy code has to be re-used or informationabout the exact timing behavior is needed. In order to tackle thisreverse engineering problem, we present CoreTAna, a novel toolthat derives an AUTOSAR compliant model of a real-time systemfrom a dynamic analysis of its trace recordings. This paper givesan overview of CoreTAna's current features and discusses itsbenefits for reverse engineering. KW - AUTOSAR KW - tracing KW - profiling KW - timing model KW - reverse engineering Y1 - 2016 U6 - https://doi.org/10.1109/SANER.2016.36 ER - TY - CHAP A1 - Waegemann, Tobias A1 - Langer, Tobias A1 - Mottok, Jürgen A1 - Osinski, Lukas A1 - Stappert, Friedhelm A1 - Tayakoli Kolagari, Ramin T1 - Models for Dependable Heterogenous Multi- and Many-Core System Software Design Revisited T2 - ARCS 2016, 29th International Conference on Architecture of Computing Systems, 4-7 April 2016, Nuremberg, Germany N2 - Modelling approaches have to satisfy certain criteria in order to sufficiently encompass the characteristics of dependable heterogenous multi- and many-core system architectures. This work-in-progress paper gives an overview of modern modelling approaches and their related research projects, particularly those regarding domain specific architecture description languages, as well as of the specific challenges of dependable systems and heterogenous multi- and many-core designs, i.e. scheduling techniques for real-time requirements and concerns regarding functional safety. Furthermore, an ongoing research effort in order to identify a set of criteria for evaluating the eligibility of modelling approaches for the task of adequately representing these systems and their specific characteristics is presented. Y1 - 2016 ER - TY - CHAP A1 - Mottok, Jürgen A1 - Merk, Josef A1 - Falter, Thomas T1 - A multi dimensional view of the Graves value systems model on teaching and learning leading to a students-centered learning: Graves model revisited T2 - IEEE Global Engineering Education Conference (EDUCON), 10-13 April 2016, Abu Dhabi, UAE N2 - A cultural change at the university eco-system is possible with diverse learning approaches in faculties. Diverse learning offers will cope with the diversity of students regarding their value systems. Currently teaching at universities is dominated by "teacher-centered teaching", also there are approaches to use different methods to accelerate and intensify the teaching and learning process. Nevertheless these approaches do often not show the desired impact with all students. This paper is offering insights how that comes using the Graves value systems model and is proposing a set of methods which fits to different value systems of students. KW - Graves Value Systems Model KW - Teaching methods KW - Students-centered teaching KW - Inside-outside classroom learning , KW - Scaffolding KW - Cultural set up Y1 - 2016 U6 - https://doi.org/10.1109/EDUCON.2016.7474600 SP - 503 EP - 512 ER - TY - CHAP A1 - Haas, Kerstin A1 - Mottok, Jürgen T1 - Research oriented learning in a research association - Evaluated in a maturity model T2 - Teaching and Learning in a Digital World, Proceedings of the 20th International Conference on Interactive Collaborative Learning (ICL), September 27 to 29, 2017, in Budapest, Hungary - Volume 1 N2 - Research-oriented learning provides students the opportunity to develop their research competences by experiencing research practice, this often happens in the surrounding of research associations with different universities and companies. This paper introduces a two-step approach to evaluate the research-oriented learning within a research association. First we conduct the evaluation of the research environment with the instrument of the adapted Collaboration Maturity Model (Col-MM) to see whether the collaboration network and the management is able to support the students in their learning process. Additionally, we take into account the evaluation of the students’ research competence. This approach targets the assessment of the starting conditions of the students and to compare their performance level until the end of the research association project phase. These two evaluation phases provide the potential to create an ideal research environment and consequently enable the students to develop and improve their research competence. Y1 - 2017 U6 - https://doi.org/10.1007/978-3-319-73210-7_81 SP - 695 EP - 701 ER - TY - CHAP A1 - Tao, Ye A1 - Liu, Guozhu A1 - Mottok, Jürgen A1 - Hackenberg, Rudolf A1 - Hagel, Georg T1 - Ranking task activity in teaching software engineering T2 - IEEE Global Engineering Education Conference (EDUCON), 10-13 April 2016, Abu Dhabi, UAE N2 - In this research, we investigate the possibility of applying ranking task activity in teaching and learning software engineering courses. We introduce three types of ranking tasks, conceptual-, contextual- and sequential ranking questions, which cover most core topics such as requirement analysis, architecture design and quality validation in the course. We have also done experiments on a group of students to see if ranking tasks could increase their conceptual knowledge in specific areas. Assessments were given in order to evaluate the effectiveness of this activity, showing an obvious increase in complex conceptual understanding. Y1 - 2016 U6 - https://doi.org/10.1109/EDUCON.2016.7474678 SP - 1023 EP - 1027 ER - TY - CHAP A1 - Soska, Alexander A1 - Mottok, Jürgen A1 - Wolff, Christian T1 - A Study on Cognitive Decits in Learning to Program T2 - European Conference of Software Engineering Education (ECSEE2016), 30 June and 1 July 2016 in Seeon Monastery, Germany N2 - For many students learning to program is a crucial task. In this research, we took a glance into the current literature and identified most ocurring cognitive deficits. Thereby we identified three elements that apear most significant throughout the study. We think that these deficits are fundamental basics for learning how to program. The stu-dents' education of cognitive abilities in programming needs revision and should receive far more training. In future research we want to establish a guideline for promoting these deficits through adequate teaching and learning arrangements in pre-programming education. Y1 - 2016 UR - https://www.researchgate.net/publication/304988534_A_Study_on_Cognitive_Deficits_in_Learning_to_Program SP - 209 EP - 214 PB - Shaker CY - Aachen ER - TY - CHAP A1 - Beslmeisl, Magdalena A1 - Reuter, Rebecca A1 - Mottok, Jürgen ED - Auer, M. ED - Guralnick, D. ED - Uhomoibhi, J. T1 - Importance of Writing in Software Engineering Education T2 - Interactive Collaborative Learning, ICL 2016, proceedings of the 19th ICL Conference, Volume 1 N2 - In this paper we present our first steps in defining the type, scope and relevance of writing in higher education of software engineering. We aim to identify lacks of scientific research and raise a new and necessary research interest to push research in this area. First we clarify the relevance of writing in higher education in general. In a second step we highlight the relevance of writing in the domain of software engineering in particular. Soft skills to be taught to students of engineering professions and especially to software engineering students are highly discussed. We discuss the skill of writing from a theoretical view as well as reasons for the high relevance of this skill for future engineers. An obligation of teaching writing in the higher education is formulated. Y1 - 2016 U6 - https://doi.org/10.1007/978-3-319-50337-0_29 SP - 315 EP - 321 ER - TY - CHAP A1 - Haas, Kerstin A1 - Mottok, Jürgen T1 - Evaluation of the Research-oriented Learning Environment in a Research Association T2 - 9th International Conference on Education and New Learning Technologies, EDULEARN2017, 3-5 July 2017, Barcelona, Spain, Proceedings Y1 - 2017 U6 - https://doi.org/10.21125/edulearn.2017.0872 ER - TY - CHAP A1 - Kampmann, Matthias A1 - Mottok, Jürgen T1 - A ‘laboratory’ as an approach to foster writing skills at software engineering studies learning software engineering is easier when writing courses are directly dpplied to lecture’s content and the problems and examples enrolled in T2 - 2018 IEEE Global Engineering Education Conference, EDUCON 2018, Santa Cruz de Teneriffe, Spanien N2 - Writing, with no doubt, is besides reading a core competency which allows us to "exploit" knowledge in general. It also makes possible the exploration of software engineering's core issues. Especially within this context it is necessary to master the reading of complex texts as well as to be able to write in an appropriate academic expression. With regard to studies in software engineering this seems to be obvious, but in fact the opposite is the reality. Therefore measures to improve these skills seemed to be necessarily applied. At the Ostbayerische Technische Hochschule (OTH, University of Applied Sciences, Regensburg) a new format, the so called c*lab, was installed during the winter semester 2017. This was a course which followed the principle of "Writing Across the Curriculum" (WAC). Organized parallel to a lecture of learning how to program the language C, and addressing students of the first semester, the course was a complete voluntary offer in addition to the general standard courses and lectures of the faculty. Students who participated not only reflected on C and its principles, nor only on writing as a self purpose, but they also learned to express technical thoughts and ideas by the use of didactic methods. The idea to transfer also basic LTeX concepts to write a paper based on the IEEE bare_conf.tex-template were also planned. The course followed the idea of student's-centred learning. This paper presents the main structure, goals, and means of the c*lab, and the theory behind. It also embeds the course within the horizon of experiences of teaching writing skills at the Laboratory for Safe and Secure Systems (LaS 3 ) at the faculty of electronic and information engineering at the OTH Regensburg. First experiences have shown that participants increase writing skills and their idea of the importance of writing. Y1 - 2018 U6 - https://doi.org/10.1109/EDUCON.2018.8363326 SP - 900 EP - 908 ER - TY - CHAP A1 - Lalo, Erjola A1 - Weber, Raphael A1 - Sailer, Andreas A1 - Mottok, Jürgen A1 - Siemers, Christian T1 - On Solving Task Allocation and Schedule Generation for Time-Triggered LET Systems using Constraint Programming T2 - 32nd International Conference on Architecture of Computing Systems, ARCS Workshop 2019, 20-21 May 2019, Copenhagen, Denmark N2 - The amount of safety-critical embedded systems in automotive development is heavily growing. Ensuring their reliability not only increases the complexity of functions but also requires determinism at design and execution time, which is considerably challenging to fulfill and verify for multi-core processors. The Logical Execution Time (LET) is recently recognized in automotive industry as an approach for ensuring deterministic functional behavior. However, to decrease the manual design effort and time for deploying such complex systems to multi-core platforms and for ensuring their strict timing and safety requirements, automatic solutions are needed. This work presents a solution for allocating tasks to multi-core processors and generating a time-triggered schedule for embedded systems considering safety, timing, and LET semantics. The approach we propose solves both challenges by defining them as a Constraint Satisfaction Problem (CSP). To examine our CSP formulation, we use MiniZinc, which is a solver-independent constraint modeling language that can employ a variety of solvers. In a case study, we explore optimizations of an industrial system that are enabled by scheduling and task allocation design decisions. Further, the performance of the proposed solutions is evaluated based on large set of synthetically generated system models. Y1 - 2019 UR - https://ieeexplore.ieee.org/abstract/document/8836201 SP - 1 EP - 8 ER - TY - CHAP A1 - Schmid, Michael A1 - Langer, Tobias A1 - Osinski, Lukas A1 - Mottok, Jürgen T1 - Parallel Active Object Pattern T2 - 31th International Conference on Architecture of Computing Systems, ARCS Workshop 2018,9-12 April 2018, Braunschweig, Germany N2 - With parallel applications becoming more and more popular even in real-time systems, the demand for safe and easyto- use software libraries and frameworks for parallel and concurrent computations is growing immensely. These frameworks usually provide an implementation for different sets of software patterns. A very well known software pattern for concurrency is the Active Object pattern, that allows various threads to have synchronized access to an object in question. This paper presents the Parallel Active Object pattern, which extends the common Active Object pattern to support the use of objects, whose computations are profoundly enhanced by a parallel execution. Furthermore, a C++ software framework is introduced, which implements the Parallel Active Object pattern and thus provides the possibility of using task or data parallel patterns, for example Map, Reduce and Divide-and-Conquer, on the active object's calculations. The proposed framework is evaluated against two other popular libraries, namely OpenMP and Intel Threading Building Blocks. Through utilization of the C++11 standard and template classes a simple user interface is provided, which abstracts the distribution of workloads among the worker threads. By making use of the C++ Standard Template Library the framework can easily be ported to embedded systems and by extending the pattern through real-time capabilities, which ensure a timely and reliable execution of the method requests, the intention of providing the framework for time critical environments is also targeted in the future. Y1 - 2018 UR - https://ieeexplore.ieee.org/document/8385426 SN - 978-3-8007-4559-3 ER - TY - CHAP A1 - Reuter, Rebecca A1 - Hauser, Florian A1 - Muckelbauer, Daniel A1 - Stark, Theresa A1 - Antoni, Erika A1 - Mottok, Jürgen A1 - Wolff, Christian T1 - Using augmented reality in software engineering education? First insights to a comparative study of 2D and AR UML modeling T2 - Proceedings of the 52nd Hawaii International Conference on System Sciences (HICSS) and 31st Conference on Software Engineering Education and Training (CSEE&T), January 8 - 11, 2019 Grand Wailea, Hawaii N2 - Although there has been much speculation about the potential of Augmented Reality (AR) in teaching for learning material, there is a significant lack of empirical proof about its effectiveness and implementation in higher education. We describe a software to integrate AR using the Microsoft Hololens into UML (Unified Modeling Language) teaching. Its user interface is laid out to overcome problems of existing software. We discuss the design of the tool and report a first evaluation study. The study is based upon effectiveness as a metric for students performance and components of motivation. The study was designed as control group experiment with two groups. The experimental group had to solve tasks with the help of the AR modeling tool and the control group used a classic PC software. We identified tendencies that participants of the experimental group showed more motivation than the control group. Both groups performed equally well Y1 - 2019 U6 - https://doi.org/10.24251/HICSS.2019.938 SP - 7798 EP - 7807 ER - TY - CHAP A1 - Nagengast, Christian A1 - Osinski, Lukas A1 - Mottok, Jürgen T1 - Synchronization Techniques for Parallel Redundant Execution of Applications T2 - 32nd International Conference on Architecture of Computing Systems, ARCS Workshop 2019, 20-21 May 2019, Copenhagen, Denmark N2 - In fault tolerant systems, applications are replicated and executed to enable error detection and recovery. If one replica application fails, another is able to take its place and provide the correct results. This concept can benefit from parallel execution on separate execution units. The rise of multicore platforms supports the development of parallel software, by providing the adequate hardware. However, this raises challenges regarding the synchronization of the redundant strings of execution. Replica determinism means that given the same input, identical programs provide the same output. To ensure replica determinism, requirements regarding the synchronization can be split in two domains: data and time. This paper examines the state of the art of synchronization techniques for parallel replicated execution in the context of fault tolerant systems. We analyze the requirements regarding synchronization within the time and data domain and compare different concepts of hardware (multicore, multiprocessor and multi-PCB) and software (processes, threads). Y1 - 2019 UR - http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=8836209&isnumber=8836190 SP - 1 EP - 8 PB - IEEE ER - TY - CHAP A1 - Reuter, Rebecca A1 - Jahn, Sabrina A1 - Figas, Paula A1 - Bartel, Alexander A1 - Mottok, Jürgen A1 - Hagel, Georg T1 - Learning Tasks for Software Engineering Education: An exemplary development of learning tasks for software engineering based on didactic function and knowledge type T2 - Proceedings of the 3rd European Conference of Software Engineering Education (ECSEE'18), JUne 2018, Seeon, Bavaria, Germany N2 - Learning tasks play an important role in education and especially in higher education. However, there is a significant lack in research regarding these in higher education. A learning task shows several characteristics, whereas the didactic function of a task is mostly considered. Two characteristics of learning tasks are focused in this paper: The didactic function and the type knowledge. Existing types of learning tasks are presented as well as a proposal for learning tasks in software engineering education that considers didactic functions, like elaboration, training or application and types of knowledge, i.e. factual, conceptual, procedural and metacognitive knowledge. This paper aims to serve as a guidance for lecturers who have the purpose to create learning tasks that address both characteristics -- the didactic function and the type of knowledge. Y1 - 2018 U6 - https://doi.org/10.1145/3209087.3209097 SP - 1 EP - 7 ER - TY - CHAP A1 - Tomer, Amir A1 - Hagel, Georg A1 - Mottok, Jürgen A1 - Alt, Dorit A1 - Barak, Miriam I. A1 - Hadar, Irit T1 - CAPELLA: A conceptual framework for adaptive life-long learning T2 - IEEE Global Engineering Education Conference (EDUCON), 25-28 April 2017, Athens, Greece N2 - In this paper we describe a proposed framework for Cooperative Adaptive Personalized Education for Life-long Learning and Activation (CAPELLA). CAPELLA comprises four models: A Knowledge Organization Model, a Learning Process Model, a Community Collaboration Model and a Gaming Model. The underlying pedagogical approach is based on the four pillars of learning: Learning to know, learning to do, learning to collaborate and learning to be. Based on these models and principles, CAPELLA provides a theoretical framework that may assist IT developers to develop state-of-the-art educational platforms and advanced learning applications. Using an example of a UML Diagramming Workshop we demonstrate how CAPELLA incorporates the principles of Adaptive Learning. Y1 - 2017 U6 - https://doi.org/10.1109/EDUCON.2017.7943041 SP - 1463 EP - 1472 ER - TY - CHAP A1 - Osinski, Lukas A1 - Langer, Tobias A1 - Mottok, Jürgen T1 - A Survey of Fault Tolerance Approaches at Different Architecture Levels T2 - 30th International Conference on Architecture of Computing Systems, ARCS 2017, 3-6 April 2017, Vienna, Austria N2 - In the recent years the development trends for computing platforms moved to multicore systems. Associated with this trend, feature sizes decreased with each new hardware generation and consequently led to a rise of transient and permanent error frequency in memory and CPUs. In this context, researchers presented several approaches which exploit the inherent redundancy of multicore platforms to provide fault tolerance. We present a discussion of fault tolerance approaches based on redundancy at different levels of architecture regarding theirsphereofreplication,performanceaswellaserrordetection and recovery capability. Y1 - 2017 UR - https://ieeexplore.ieee.org/document/7948561 SP - 1 EP - 9 ER - TY - RPRT A1 - Soska, Alexander A1 - Mottok, Jürgen ED - Baier, Wolfgang T1 - An Experimental Card Game for Software Testing T2 - Forschungsbericht 2017 der Ostbayersichen Technischen Hochschule Regensburg Y1 - 2017 UR - https://doi.org/10.35096/othr/pub-1383 CY - Regensburg ER - TY - CHAP A1 - Reuter, Rebecca A1 - Hauser, Florian A1 - Gold-Veerkamp, Carolin A1 - Stark, Theresa A1 - Kis, Juliane A1 - Mottok, Jürgen A1 - Abke, Jörg A1 - Meyer, Dany T1 - Towards the construction of a questionnaire for the identification of learning obstacles T2 - 2018 IEEE Global Engineering Education Conference (EDUCON 2018), 17-20 April, 2018, Santa Cruz de Tenerife, Spain N2 - This paper deals with the identification of learning ob-stacles using the questionnaire method. Therefore, two iterations were proceeded: The first one was part of a survey that was carried out at four lo-cations at universities of applied sciences. We asked students about obstructive facts in general providing items for five learning ob-stacle dimensions that were set up before; emotional/motivational, epistemological/cognitive, didactical, resource-related and meta-cognitive learning obstacle dimensions. After the general part, we asked them to answer the same question, but in relation to the – in their opinion – most difficult learning content. With this question, we aim to get indications regarding to epistemological obstacles. In a second step, we used the “Motivated Strategies for Learning Questionnaire”, which was developed by Pintrich [1] as a basis to develop a questionnaire that extracts learning obstacles. In its original version, the “Motivated Strategies for Learning Question-naire” was intended to measure students’ learning strategies, but, as the obstacle dimensions were partly derived from learning strategy classification, we chose this already validated question-naire [2]. Within this iteration, we could confirm a five-factor structure of the questionnaire that could be mapped to the five be-fore set learning obstacle dimensions. Y1 - 2018 U6 - https://doi.org/10.1109/EDUCON.2018.8363266 SP - 457 EP - 466 ER - TY - CHAP A1 - Osinski, Lukas A1 - Langer, Tobias A1 - Schmid, Michael A1 - Mottok, Jürgen T1 - PyFI – Fault Injection Plattform for Real Hardware T2 - 31th International Conference on Architecture of Computing Systems, ARCS Workshop 9-12 April 2018, Braunschweig, Germany N2 - Today, due to the rapidly evolving technology within the automotive industry, the automation level of cars is continuously increasing. As a consequence, the software code base implementing the automated driving functionality is growing in both, complexity and size. Simultaneously, the semiconductor industry continues with structure and voltage downscaling due to diminishing design margins and stringent power constraints. This trend leads to highly integrated hardware on the one hand, whilst provoking an increase in sensitivity against external causes for hardware faults, e.g., radiation effects or electromagnetic interference. Among the available dependability assessment techniques, fault injection (FI) is widely adopted and ISO 26262 strongly recommends applying it to validate, that functional and technical safety mechanisms are implemented correctly and effectively. We present PyFI (Python backend for Fault Injection), a fault injection backend for the Infineon Aurix TriCore which utilizes an iSystem On-chip Analyzer to inject faults into the application data or instructions that are visible at the assembly level. PyFI allows the injection of bit flips and stuck-at faults in memory and register cells of the hardware which trigger our error symptoms on application level. Furthermore, it implements fault collapsing algorithms to reduce the number of faults and the duration for single experiments by gathering statistics about the static and dynamic application execution. Y1 - 2018 UR - https://ieeexplore.ieee.org/document/8385427 SP - 1 EP - 7 ER - TY - BOOK A1 - Weilkiens, Tim A1 - Huwaldt, Alexander A1 - Mottok, Jürgen A1 - Roth, Stephan A1 - Willert, Andreas T1 - Modellbasierte Softwareentwicklung für eingebettete Systeme verstehen und anwenden N2 - Die Beherrschung von Komplexität ist eine der größten Engineering-Herausforderungen des 21. Jahrhunderts. Themen wie das „Internet der Dinge“ (IoT) und „Industrie 4.0“ beschleunigen diesen Trend. Die modellgetriebene Entwicklung leistet einen entscheidenden Beitrag, um diesen Herausforderungen erfolgreich begegnen zu können. Die Autoren geben einen fundierten Einstieg und praxisorientierten Überblick über die Modellierung von Software für eingebettete Systeme von den Anforderungen über die Architektur bis zum Design, der Codegenerierung und dem Testen. Für jede Phase werden Paradigmen, Methoden, Techniken und Werkzeuge beschrieben und ihre praktische Anwendung in den Vordergrund gestellt. Darüber hinaus wird auf die Integration von Werkzeugen, funktionale Sicherheit und Metamodellierung eingegangen sowie die Einführung eines modellbasierten Ansatzes in einer Organisation und die Notwendigkeit zum lebenslangen Lernen erläutert. Der Leser erfährt in diesem Buch, wie ein modellbasiertes Vorgehen nutzbringend in der Praxis für die Softwareentwicklung eingesetzt wird. Das Vorgehen wird unabhängig von Modellierungswerkzeugen vorgestellt. Zahlreiche Beispiele – exemplarisch auch auf Basis konkreter Werkzeuge – helfen bei der praktischen Umsetzung. Y1 - 2018 SN - 978-3-86490-524-7 PB - dpunkt.Verlag CY - Heidelberg ER - TY - CHAP A1 - Hauser, Florian A1 - Gegenfurtner, Andreas A1 - Hutzler, Ivonne A1 - Reuter, Rebecca A1 - Mottok, Jürgen T1 - Eye movement patterns in source code review T2 - EARLI SIG 17 and 25 Biennial Conference 2018, Cambridge, United Kingdom N2 - This study is based on the work of Uwano, Nakamura, Monden and Matsumoto (2006) who tried to identify programmers’ eye movements in source code reviews by using eye tracking technology. The researchers were able to identify certain eye movement patterns but due to the technical limitations of earlier eye tracking systems and a small sample they could not find a valid proof for their existence. Now, twelve years later, the eye tracking technology has made significant improvements and is able to capture programmers’ reading behavior in an unobtrusive and precise way. Now the goal is to verify the described patterns by using eye tracking data from expert and novice programmers. In the experiment they have to detect errors in six different codes and take part in a retrospective interview. At the moment, data collections are ongoing. At the time of the conference, we will present the results of our analyses. Y1 - 2018 ER - TY - CHAP A1 - Reuter, Rebecca A1 - Knietzsch, Marco A1 - Hauser, Florian A1 - Mottok, Jürgen T1 - Supporting Abstraction Skills Using Augmented Reality? T2 - ITiCSE '19, Proceedings of the 2019 ACM Conference on Innovation and Technology in Computer Science Education, July 2019, Aberdeen Scotland UK N2 - We investigated the potential of augmented reality (AR) to enable visualization of abstract concepts and present the first iteration of a teaching experiment that evaluates the use of AR as support for abstraction skills. Students were confronted with the task to present and explain information to different groups of stakeholders at the example of a coffee machine. Results show that students find it helpful to have a visual app-prototype and especially one that can be disassembled in different levels. The main goal was to sensitize students for the need to think about and to abstract information for certain roles and perspectives. Y1 - 2019 U6 - https://doi.org/10.1145/3304221.3325562 ER - TY - CHAP A1 - Hutzler, Ivonne A1 - Hauser, Florian A1 - Reuter, Rebecca A1 - Mottok, Jürgen A1 - Gruber, Hans T1 - Will the noun/verb analysis be used to generate class diagrams? An eye tracking study T2 - IATED, 11th International Conference of Education, Research and Innovation (ICERI 2018), 12-14 November 2018, Seville, Spain Y1 - 2018 U6 - https://doi.org/10.21125/iceri.2018.1103 SP - 505 EP - 514 ER - TY - CHAP A1 - Hauser, Florian A1 - Mottok, Jürgen A1 - Reuter, Rebecca A1 - Hutzler, Ivonne A1 - Gruber, Hans T1 - Eye movement patterns in software engineering – What differs the expert from the novice? T2 - IATED, 11th International Conference of Education, Research and Innovation (ICERI 2018), 12-14 November 2018, Seville, Spain Y1 - 2018 U6 - https://doi.org/10.21125/iceri.2018.1129 ER - TY - CHAP A1 - Osinski, Lukas A1 - Langer, Tobias A1 - Mader, Ralph A1 - Mottok, Jürgen T1 - Challenges and Opportunities with Embedded Multicore Platforms BT - Spotlight on Real-Time and Dependability Concepts T2 - 9th European Congress Embedded Real Time Software and Systems (ERTS 2018), January 31st to Febraury 2nd 2018, Toulouse, France Y1 - 2018 UR - https://hal.archives-ouvertes.fr/hal-02156232/ ER - TY - RPRT A1 - Hauser, Florian A1 - Mottok, Jürgen ED - Baier, Wolfgang T1 - Eye movement patterns im Software Engineering T2 - Forschung 2018 / Ostbayerische Technische Hochschule Regensburg Y1 - 2018 UR - https://doi.org/10.35096/othr/pub-1382 SP - 48 EP - 49 ER - TY - CHAP A1 - De, Sangita A1 - Niklas, Michael A1 - Rooney, Brian A1 - Mottok, Jürgen A1 - Brada, Premek T1 - Towards Translation of Semantics of Automotive Interface Description Models from Franca to AUTOSAR Frameworks BT - An Approach using Semantic Synergies T2 - 2019 International Conference on Applied Electronics (AE), 10-11 Sept. 2019, Pilsen, Czech Republic N2 - The automotive industry is eventually evolving into a complex network of services. The heterogeneous and distributed nature of automotive software systems demands flexible software components which can operate in different environments. Because of heterogeneous automotive development environments, the domain experts, must cope with too many diversities, adaption layers, and incompatibilities to design applications for the current generation of autonomous driving vehicles. In this context, interface adaptation is a promising approach to achieve flexibility without directly changing the respective components. AUTOSAR, which is the de-facto standard for describing automotive system architecture and is a hugely comprehensive standard allowing designers full control from abstract system description to bare metal level deployment. However, the vehicle subsystems have still evolved to include multifarious high-level domains not covered by AUTOSAR e.g. Infotainment, Telematics etc. Therefore, it seems beneficial to bridge the semantic gaps between AUTOSAR applications and other standards of automotive application domains. The goal of this paper is to investigate interface semantic mapping and achieve transparent integration of domain-specific applications using the translation of semantics among the AUTOSAR platform software component models and other software components models of open source development platforms e.g. GENIVI. A key goal of such a modelling approach is the reuse of existing interface description languages and respective code generators. This will enhance future interoperability and decrease in incompatibility among these platforms. KW - Adaptation models KW - ARXML KW - Automotive engineering KW - component model KW - Connectors KW - FRAMEWORK KW - Franca IDL KW - interface KW - Receivers KW - semantic KW - synergy KW - traits Y1 - 2019 U6 - https://doi.org/10.23919/AE.2019.8867018 SP - 1 EP - 6 PB - University of West Bohemia ER - TY - CHAP A1 - De, Sangita A1 - Mottok, Jürgen A1 - Brada, Premek ED - Pinker, Jiří T1 - Design Approach to Platform Agnostic Service API Modeling for Interoperability of Cross-enterprise Vehicle Applications T2 - 26th 2021 International Conference on Applied Electronics (AE): 7-8 September 2021, University of West Bohemia, Pilsen, Czech Republik N2 - In the last few years, the collaboration of services between the service-oriented, cross-enterprise vehicle application frameworks has gradually increased to generate novel and more complicated vehicle services for the automotive industry. In these service collaboration scenarios, where heterogeneous application frameworks participate to realize complex vehicle services, a source of discord that emerges is that the service providers must always check, before the service deployment, whether the clients or service consumers on the other side of the communication link are compatible with a given service's API (Application Program Interface). While using standardized templates like ontologies for API's semantic specifications are crucial for a service discovery and semantic interoperability, nevertheless, accessing these service APIs' semantic data using a standardized and understandable syntactical specification template is also equally substantial to ease services interoperability. In fact, such complex service collaboration scenarios motivate this research work which proposes a design approach towards standardized, domain-specific, platform-agnostic semantic and syntactic specification of vehicle services API models. This paper also uses a typical vehicle domain case study to illustrate the design approach and a reference mapping between the platform-agnostic semantics specifications of a vehicle service API ontological model and its corresponding language-neutral, syntactic representation using the OpenAPI standard. KW - interoperability KW - Semantic Web KW - API KW - RESTful KW - ontology Y1 - 2021 SN - 978-80-261-0973-0 U6 - https://doi.org/10.23919/AE51540.2021.9542890 SP - 1 EP - 6 PB - IEEE ER - TY - CHAP A1 - Schmid, Michael A1 - Mottok, Jürgen ED - Queudet, Audrey T1 - Response Time Analysis of Parallel Real-Time DAG Tasks Scheduled by Thread Pools T2 - 29th International Conference on Real-Time Networks and Systems (RTNS 2021): 07.04. - 09 04 2021, Nantes, France N2 - Modern high-end embedded systems nowadays have to process enormous amounts of data. In order to speed up the computations and fully exploit the resources of the underlying hardware architectures, software developers can avail parallelism frameworks such as Intel Threading Building Blocks or compiler extensions as OpenMP. They ease the development of parallel applications by providing interfaces for common parallel design patterns and by internally distributing the work among the workers of a thread pool. However, such frameworks and compiler extensions do not yet support the stringent timing requirements of real-time systems and therefore, an adaption of their computation model to the sector of real-time systems needs to be conducted. In this paper, we address the problem of scheduling parallel real-time directed acyclic graphs tasks on multiprocessor architectures where the subtasks are dispatched among and executed by the workers of a thread pool. In contrast to existing work in the state-of-the-art, we limit the maximum parallelism of real-time tasks not by the number of processors in the system, but by the number of worker threads used in the thread pool of each real-time application. For this model, we derive a worst-case response time analysis for task sets scheduled by a preemptive global fixed-priority scheduler. In order to evaluate the performance of our response time analysis, we further perform schedulability tests on generated task sets and compare the results to existing feasibility analyses in the current state-of-the-art. KW - directed acyclic graph KW - parallel task KW - Real-time systems KW - real-time, scheduling KW - response time analysis KW - thread pool Y1 - 2021 SN - 9781450390019 U6 - https://doi.org/10.1145/3453417.3453419 SP - 173 EP - 183 PB - Association for Computing Machinery CY - New York ER - TY - CHAP A1 - De, Sangita A1 - Niklas, Michael A1 - Mottok, Jürgen A1 - Brada, Přemek T1 - A Semantic Analysis of Interface Description Models of Heterogeneous Vehicle Application Frameworks: An Approach Towards Synergy Exploration T2 - MODELSWARD 2019: Proceedings of the 7th International Conference on Model-Driven Engineering and Software Development, 20.02.2019 - 22.02.2019, Prague, Czech Republic N2 - As the world is getting more connected, the demands of services in automotive industry are increasing with the requirements such as IoT (Internet of Things) in cars, automated driving, etc. Eventually, the automotive industry has evolved to a complex network of servi ces, where each organization depends on the other organizations, to satisfy its service requirements in different phases of the vehicle life cycle. Because of these heterogeneous and complex development environments, most of the vehicle component interface models need to be specified in various manifest ations to satisfy the semantic and syntactic requirements, specific to different application development environments or frameworks. This paperdescribes an approach to semantic analysis of components interfaces description models of heterogeneous frameworks, that are used for vehicle applications. The proposed approach intends to ensure that interface description models of different service-based vehicle frameworks can be compared, correlated and re-used based on semantic synergies, across different vehicle platforms, development environments and organizations. The approach to semantic synergy exploration could further provide the knowledge base for the increase in interoperability, overall efficiency and development of an automotive domain specific general software solutions, by facilitating coexistence of components of heterogeneous frameworks in the same high-performance ECU for future vehicle software. KW - Application: Framework KW - IDL KW - Semantic: Mapping Y1 - 2019 SN - 978-989-758-358-2 SP - 394 EP - 401 PB - SCITEPRESS ER - TY - RPRT A1 - Taiber, Joachim A1 - Chowdury, M. A1 - Hammond, G. A1 - Hipp, V. A1 - Huttner, B. A1 - Lonien, J. A1 - Mottok, Jürgen A1 - Neukart, F. A1 - Stengel, T. T1 - Unsettled Topics Concerning the Impact of Quantum Technologies on Automotive Cybersecurity N2 - Quantum computing is considered the “next big thing” when it comes to solving computational problems impossible to tackle using conventional computers. However, a major concern is that quantum computers could be used to crack current cryptographic schemes designed to withstand traditional cyberattacks. This threat also impacts future automated vehicles as they become embedded in a vehicle-to-everything (V2X) ecosystem. In this scenario, encrypted data is transmitted between a complex network of cloud-based data servers, vehicle-based data servers, and vehicle sensors and controllers. While the vehicle hardware ages, the software enabling V2X interactions will be updated multiple times. It is essential to make the V2X ecosystem quantum-safe through use of “post-quantum cryptography” as well other applicable quantum technologies. This SAE EDGE™ Research Report considers the following three areas to be unsettled questions in the V2X ecosystem: How soon will quantum computing pose a threat to connected and automated vehicle technologies? What steps and measures are needed to make a V2X ecosystem “quantum-safe?” What standardization is needed to ensure that quantum technologies do not pose an unacceptable risk from an automotive cybersecurity perspective? Y1 - 2020 U6 - https://doi.org/10.4271/EPR2020026 SN - 2640-3536 CY - Warrendale, Pennsylvania, USA ER - TY - GEN A1 - Hauser, Florian A1 - Reuter, Rebecca A1 - Gegenfurtner, Andreas A1 - Gruber, Hans A1 - Mottok, Jürgen A1 - Hutzler, Ivonne T1 - Heuristics in Software Modelling: An Eyetracking Study T2 - Earli Book of Abstracts N2 - To investigate the role of heuristics in the domain of software engineering, an eye tracking study was conducted in which experts and novices were compared. The study focused on one of the most challenging parts in this domain: the generation of an object model for a software product based on a requirements specification. During their training, software engineers are taught different techniques to solve this task. One of these techniques is the noun/verb analysis. However, it is still unclear to what extent novice and expert programmers are making use of it. Ideally, the noun/verb analysis works as a heuristic and helps programmers to make fast and accurate decisions. Participants in the study were 40 software programmers at four levels of expertise (novices, intermediates, experienced rogrammers, experts). They were presented with ten decision tasks. In each task, participants read a requirement specification and then had to choose one out of three presented class diagrams that they considered the best solution. During the task, their eye movements were recorded. Results show that all participants used the noun/verb analysis as a heuristic. Programmers with higher levels of expertise, however, outperformed programmers with lower levels of expertise. Interestingly, the more experienced programmers were not following the noun/verb analysis in a blindfolded way. They realised that the noun/verb analysis would produce diagrams, but a skilled software architect would not model them in this way. Instead they created their models in a way that they perceived as more logical and realistic Y1 - 2019 UR - https://earli.org/sites/default/files/2019-09/BOA-2019.pdf PB - RWTH Aachen ER - TY - JOUR A1 - Diermeier, Andreas A1 - Sindersberger, Dirk A1 - Krenkel, Lars A1 - Rosell, X. C. A1 - Monkman, Gareth J. T1 - Controllable Magnetoactive Polymer Conduit JF - The Open Mechanical Engineering Journal N2 - Objective: Magneto-active Polymers (MAP) are smart materials whose mechanical characteristics, such as elastic and shear moduli, may be controllable by means of an externally applied magnetic field. Methods: Various additives may be used to influence the characteristics of the polymer matrix whilst a suspension of soft and/or hard magnetic particles determine the magnetic properties of the composite. Both pre-cure and post-cure magnetization is possible. Results: A range of control strategies have been investigated for evaluation of the system using fluids of differing kinematic viscosity. Conclusion: Depending on the degree of magnetic field homogeneity, magneto-deformation and magnetostriction contribute to MAP actuation. This paper presents a novel application in the form of a peristaltic MAP tube system, applicable to flow control and pumping of hemorheological fluids in blood circulatory systems for biomedical research purposes. Y1 - 2018 UR - https://www.benthamopen.com/ABSTRACT/TOMEJ-12-192 N1 - Corresponding authro: Gareth J. Monkman VL - 12 IS - 1 SP - 192 EP - 200 PB - Bentham ER - TY - JOUR A1 - Fuhrmann, Thomas A1 - Mottok, Jürgen T1 - Ethical, intercultural and professional impulses integrated into a transmission systems lecture JF - 2017 IEEE Global Engineering Education Conference (EDUCON), 25-28 April 2017, Athens, Greece N2 - In the sixth semester of the bachelor study course “Electrical Engineering and Information Technology”, a lecture “Transmission Systems” is given. It explains basic principles, circuits and systems of electrical and optical transmission systems. Short intellectual impulses, which address professional, intercultural and ethical issues of engineers' working life are integrated into this regular lecture. In each lecture unit, an impulse with one specific topic is given approximately in the middle of the lecture hour. An evaluation was done at the end of the semester, which shows that most of the students remember the discussed topics and state high interest due to high importance for their professional life. Due to these encouraging results, this concept will be developed further. KW - Engineering Education KW - Ethics Education KW - Electrical Engineering Y1 - 2017 U6 - https://doi.org/10.1109/EDUCON.2017.7942829 SP - 92 EP - 95 PB - IEEE ER - TY - JOUR A1 - Freiling, Felix A1 - Grimm, Rüdiger A1 - Großpietsch, Karl-Erwin A1 - Keller, Hubert B. A1 - Mottok, Jürgen A1 - Münch, Isabel A1 - Rannenberg, Kai A1 - Saglietti, Francesca T1 - Technische Sicherheit und Informationssicherheit. Unterschiede und Gemeinsamkeiten JF - Informatik-Spektrum Y1 - 2014 U6 - https://doi.org/10.1007/s00287-013-0748-2 VL - 37 IS - 1 SP - 14 EP - 24 PB - Springer ER - TY - CHAP A1 - Tao, Ye A1 - Liu, Guozhu A1 - Mottok, Jürgen A1 - Hackenberg, Rudolf A1 - Hagel, Georg A1 - Mottok, Jürgen T1 - Just-in-Time Teaching in software engineering: A Chinese-German empirical case study T2 - 2014 IEEE Global Engineering Education Conference (EDUCON), 3-5 April 2014, Istanbul, Turkey N2 - Learning centered teaching becomes an important factor in a global perspective of learning software engineering. The Just-in-Time Teaching approach is used in a Chinese-German empirical case study. In a one year terminated project we will analyze the performance of our students in an active learning scenario with Just-in-Time Teaching and Peer Instruction. We will contribute an inter-cultural comparison of achieved competencies by student’s self-assessment and teacher’s observation. KW - Activating Learning KW - Blended Learning KW - Conferences KW - Educational institutions KW - E-Learning KW - ISO Standards KW - JiTT KW - Just-in-Time Teaching KW - Materials KW - Practical Learning KW - Software KW - Software engineering Y1 - 2014 U6 - https://doi.org/10.1109/EDUCON.2014.6826220 SP - 983 EP - 986 PB - IEEE ER - TY - CHAP A1 - Hauser, Florian A1 - Mottok, Jürgen A1 - Gruber, Hans ED - Mottok, Jürgen T1 - Eye Tracking Metrics in Software Engineering T2 - Proceedings of the 3rd European Conference of Software Engineering Education (ECSEE'18); Seeon/ Bavaria Germany, 14.06.2018 -15.06.2018 N2 - This paper aims to provide an overview of the interdisciplinary combination of educational science, psychology, software engineering and the eye tracking methodology. The domain of software engineering is offering great potential for applied eye tracking research and in turn it can benefit from the possibilities of this upcoming technology as well. Nevertheless, software engineering has to struggle with some obstacles. These are namely the different terms, missing guidelines for experimental setups and a lack of common and standardized metrics. If eye tracking should be used in a broader way these problems must be solved. The main purpose of this paper is to list all eye tracking metrics which are relevant for software engineering and to give guidelines to help beginners by avoiding possible pitfalls. Y1 - 2018 SN - 9781450363839 U6 - https://doi.org/10.1145/3209087.3209092 SP - 39 EP - 44 PB - ACM CY - New York, NY ER - TY - GEN ED - Mottok, Jürgen T1 - Proceedings of the 3rd European Conference of Software Engineering Education (ECSEE'18); Seeon/ Bavaria Germany, 14.06.2018 -15.06.2018 Y1 - 2018 SN - 9781450363839 U6 - https://doi.org/10.1145/3209087 PB - ACM CY - New York, NY, USA ER - TY - JOUR A1 - Schmid, Michael A1 - Fritz, Florian A1 - Mottok, Jürgen T1 - Fine-grained parallelism framework with predictable work-stealing for real-time multiprocessor systems JF - Journal of Systems Architecture N2 - Lately, parallel task models have received much attention in the development of real-time multiprocessor systems, as they allow highly compute-intensive tasks to have shorter deadlines which is very much required in modern reactive systems. However, missing modularity and portability can make parallel programming a cumbersome endeavor. As a consequence, compute-intensive sectors in the desktop and server segment have relied on parallelism frameworks such as Intel Threading Building Blocks, Cilk and OpenMP. These parallelism frameworks, however, are optimized for decent average case performance and consequently, do not meet the strict requirements imposed by real-time systems. In this paper, we present a proof-of-concept parallelism framework which was implemented in particular for soft real-time systems and having tight timing and safety requirements of such critical systems in mind. The proposed runtime system implements static memory allocation in a work-stealing environment that conforms to the strict space and tight probabilistic time bounds of work-stealing schedulers. Furthermore, we evaluate the performance of this framework by conducting multiprogrammed benchmarks on a real-time embedded multicore architecture. Y1 - 2022 U6 - https://doi.org/10.1016/j.sysarc.2022.102393 N1 - Corrigendum: https://www.sciencedirect.com/science/article/pii/S1383762123000528?via%3Dihub VL - 124 IS - March PB - Elsevier ER - TY - JOUR A1 - De, Sangita A1 - Brada, Premek A1 - Mottok, Jürgen A1 - Niklas, Michael T1 - The Empirical Evaluation of Semantic Alignment Quality Metrics for Vehicle Domain Component Frameworks Interface Ontologies JF - FLAIRS 2021 : The 34th International FLAIRS Conference. Proceedings N2 - Semantic alignment of application software components’ ontologies represents a great interest in vehicle application domains that manipulate heterogeneous overlapping knowledge application frameworks. In the past few years, with the growth in the novel vehicle service requirements such as autonomous driving, V2X (Vehicle-to-Vehicle communication) and many others, automotive application software component models are becoming increasingly collaborative with other qualified cross-enterprise industrial partners to accomplish these complex service requirements. The most daunting impediment to this cross-enterprise collaboration is semantic interoperability. For efficient services collaboration through cross-enterprise semantic interoperability between the vehicle application frameworks’ software components, aligning the interface ontologies of these components by identifying the depth of semantic alignment relationships between the concepts of the interface ontologies is the major focus of this paper. In contrast to several existing ontology structural metrics, this work defines, evaluates and validates ontology metrics to measure the depth of semantic alignment between the vehicle domain software component frameworks’ interface ontological models. To emphasize the substantial role of semantic alignment of software component frameworks’ interface ontologies in semantic interoperability, a typical vehicle domain case study involving vehicle applications is considered for demonstration. Y1 - 2021 U6 - https://doi.org/10.32473/flairs.v34i1.128512 VL - 34 IS - 1 PB - LibraryPress@UF ER - TY - CHAP A1 - Frauenschläger, Tobias A1 - Mottok, Jürgen T1 - Security-Gateway for SCADA-Systems in Critical Infrastructures T2 - 27th International Conference on Applied Electronics (AE): 06-07 September 2022, Pilsen, CZ N2 - Supervisory Control and Data Acquisition (SCADA) systems are used to control and monitor components within the energy grid, playing a significant role in the stability of the system. As a part of critical infrastructures, components in these systems have to fulfill a variety of different requirements regarding their dependability and must also undergo strict audit procedures in order to comply with all relevant standards. This results in a slow adoption of new functionalities. Due to the emerged threat of cyberattacks against critical infrastructures, extensive security measures are needed within these systems to protect them from adversaries and ensure a stable operation. In this work, a solution is proposed to integrate extensive security measures into current systems. By deploying additional security-gateways into the communication path between two nodes, security features can be integrated transparently for the existing components. The developed security-gateway is compliant to all regulatory requirements and features an internal architecture based on the separation-of-concerns principle to increase its security and longevity. The viability of the proposed solution has been verified in different scenarios, consisting of realistic field tests, security penetration tests and various performance evaluations. KW - Critical Infrastructure KW - Certification KW - Supervisory Control and Data Acquisition KW - Security KW - Dependability Y1 - 2022 U6 - https://doi.org/10.1109/AE54730.2022.9920070 PB - IEEE ER - TY - CHAP A1 - Pozzobon, Enrico A1 - Renner, Sebastian A1 - Mottok, Jürgen A1 - Matoušek, Václav T1 - An optimized Bitsliced Masked Adder for ARM Thumb-2 Controllers T2 - 27th International Conference on Applied Electronics (AE): Sep 6, 2022 - Sep 7, 2022, Pilsen, Czech Republic N2 - The modular addition is used as a non-linear operation in ARX ciphers because it achieves the requirement of introducing non-linearity in a cryptographic primitive while only taking one clock cycle to execute on most modern architectures. This makes ARX ciphers especially fast in software implementations, but comes at the cost of making it harder to protect against side-channel information leakages using Boolean masking: the best known 2-shares masked adder for ARM Thumb micro-controllers takes 83 instructions to add two 32-bit numbers together. Our approach is to operate in bitsliced mode, performing 32 additions in parallel on a 32-bit microcontroller. We show that, even after taking into account the cost of bitslicing before and after the encryption, it is possible to achieve a higher throughput on the tested ciphers (CRAX and ChaCha20) when operating in bitsliced mode. Furthermore, we prove that no first-order information leakage is happening in either simulated power traces and power traces acquired from real hardware, after sufficient countermeasures are put into place to guard against pipeline leakages. KW - ARM Thumb KW - bitsliced KW - side-channel KW - Boolean masking Y1 - 2022 U6 - https://doi.org/10.1109/AE54730.2022.9919884 PB - IEEE ER - TY - CHAP A1 - Schmid, Michael A1 - Mottok, Jürgen T1 - Investigation of Scheduling Algorithms for DAG. Tasks through Simulations T2 - ERTS 2022, 11th European Congress Embedded Real Time Systems: 1-2 June, Toulouse, France N2 - In the real-time systems sector, various task models and corresponding tests exist to model and verify the schedulability of task sets on the system at hand. While those models and schedulability tests have intensively been studied from a theoretical point of view, it is hard to ma e use of them to compare the actual execution behavior of scheduling algorithms on a real system. In contrast to schedulability tests, simulators can help to investigate the performance of specific scheduling algorithms. One of the most generalized task models to describe parallel tasks is the Directed Acyclic Graph model that allows to represent tasks as a series of subtasks that depict the potentially parallel computations and precedence constraints that denote the order in which the subtasks are allowed to execute. In this paper, we investigate various scheduling algorithms for the Directed Acyclic Graph model. For that, we first recapitulate the examined scheduling algorithms in detail and point out relevant differences. Subsequently, we present the evaluation of different global and federated scheduling algorithms using fine-grained parallel tasks. To this end, we generate random Directed Acyclic Graph tasks and simulate their execution on multiprocessor systems using scheduling algorithms such as global rate-monotonic and semi-federated scheduling as well as global scheduling policies using the thread pool model. KW - real-time KW - scheduling KW - task models KW - simulation Y1 - 2022 UR - https://hal.archives-ouvertes.fr/hal-03700472/document ER - TY - CHAP A1 - Grabinger, Lisa A1 - Hauser, Florian A1 - Mottok, Jürgen T1 - Accessing the Presentation of Causal Graphs and an Application of Gestalt Principles with Eye Tracking T2 - 2022 IEEE International Conference on Software Analysis, Evolution and Reengineering (SANER 2022), 1st Workshop on Advances in Human-Centric Experiments in Software Engineering (HUMAN 2022): 15-18 March 2022, Honolulu, HI, USA N2 - The discipline of causal inference uses so-called causal graphs to model cause and effect relations of random variables. As those graphs only encode a relation structure there is no hard rule concerning their alignment. The present paper presents a study with the aim of working out the optimal alignment of causal graphs with respect to comprehensibility and interestingness. In addition, the study examines whether the central gestalt principles of psychology apply for causal graphs. Data from 29 participants is acquired by triangulating eye tracking with a questionnaire. The results of the study suggest that causal graphs should be aligned downwards. Moreover, the gestalt principles proximity, similarity and closure are shown to hold true for causal graphs. KW - causal graphs KW - gestalt principles KW - eye tracking Y1 - 2022 U6 - https://doi.org/10.1109/SANER53432.2022.00153 SP - 1278 EP - 1285 PB - IEEE ER - TY - CHAP A1 - Münch, Andreas A1 - Frauenschläger, Tobias A1 - Mottok, Jürgen T1 - Integration of a Security Gateway for Critical Infrastructure into Existing PKI Systems T2 - 3. Symposium Elektronik und Systemintegration (ESI 2022), Tagungsband: 06. April 2022, Hochschule Landshut, Deutschland Y1 - 2022 SN - 978-3-9818439-7-2 SP - 88 EP - 97 PB - Hochschule Landshut CY - Landshut ER - TY - JOUR A1 - Fuxen, Philipp A1 - Schönhärl, Stefan A1 - Schmidt, Jonas A1 - Gerstner, Mathias A1 - Jahn, Sabrina A1 - Graf, Julian A1 - Hackenberg, Rudolf A1 - Mottok, Jürgen T1 - A Cybersecurity Education Platform for Automotive Penetration Testing JF - International Journal On Advances in Security N2 - The paper presents a penetration testing framework for automotive IT security education and evaluates its realization. The automotive sector is changing due to automated driving functions, connected vehicles, and electric vehicles. This development also creates new and more critical vulnerabilities. This paper addresses a possible countermeasure, automotive IT security education. Some existing solutions are evaluated and compared with the created Automotive Penetration Testing Education Platform (APTEP) framework. In addition, the APTEP architecture is described. It consists of three layers representing different attack points of a vehicle. The realization of the APTEP is a hardware case and a virtual platform referred to as the Automotive Network Security Case (ANSKo). The hardware case contains emulated control units and different communication protocols. The virtual platform uses Docker containers to provide a similar experience over the internet. Both offer two kinds of challenges. The first introduces users to a specific interface, while the second combines multiple interfaces, to a complex and realistic challenge. This concept is based on modern didactic theories, such as constructivism and problem-based/challenge-based learning. Computer Science students from the Ostbayerische Technische Hochschule (OTH) Regensburg experienced the challenges as part of a elective subject. In an online survey evaluated in this paper, they gave positive feedback. Also, a part of the evaluation is the mapping of the ANSKo and the maturity levels in the Software Assurance Maturity Model (SAMM) practice Education & Guidance as well as the SAMM practice Security Testing. The scientific contribution of this paper is to present an APTEP, a corresponding learning concept and an evaluation method. KW - Challenge-based Learning KW - Education Framework KW - Penetration Testing KW - Automotive KW - IT-Security Education Y1 - 2022 UR - http://www.iariajournals.org/security/sec_v15_n34_2022_paged.pdf SN - 1942-2636 VL - 15 IS - 3&4 SP - 106 EP - 118 PB - IARIA ER - TY - CHAP A1 - Renner, Sebastian A1 - Pozzobon, Enrico A1 - Mottok, Jürgen ED - Li, Wenjuan ED - Furnell, Steven ED - Meng, Weizhi T1 - Evolving a Boolean Masked Adder Using Neuroevolution T2 - Attacks and Defenses for the Internet-of-Things, 5th International Workshop, ADIoT 2022: Copenhagen, Denmark, September 30, 2022, Revised Selected Papers N2 - The modular addition is a popular building block when designing lightweight ciphers. While algorithms mainly based on the addition can reach very high performance, masking their implementations results in a huge penalty. Since efficient protection against side-channel attacks is a requirement in lots of use cases, we focus on optimizing the Boolean masking of the modular addition. Contrary to recent related work, we target evolving a masked full adder instead of parts of a parallel prefix adder. We study how techniques typically found in neural network evolution and genetic algorithms can be adapted in order to help in evolving an efficiently masked adder. We customize a well-known neuroevolution algorithm, develop an optimized masked adder with our new approach and implement the ChaCha20 cipher on an ARM Cortex-M3 controller. We compare the performance of the protected neuroevolved implementation to solutions found by traditional search methods. Moreover, the leakage of our new solution is validated by a t-test conducted with a leakage simulator. We present under which circumstances our masked implementation outperforms related work and prove the feasibility of successfully using neuroevolution when searching for complex Boolean networks. Y1 - 2022 SN - 978-3-031-21310-6 U6 - https://doi.org/10.1007/978-3-031-21311-3_2 SP - 21 EP - 40 PB - Springer Nature CY - Cham ER - TY - CHAP A1 - Homann, Alexander A1 - Grabinger, Lisa A1 - Hauser, Florian A1 - Mottok, Jürgen T1 - An Eye Tracking Study on MISRA C Coding Guidelines T2 - ECSEE '23: Proceedings of the 5th European Conference on Software Engineering Education, Seeon/Germany, June 19 - 21, 2023 N2 - C is one of the most widely used programming languages - MISRA C is one of the most known sets of coding guidelines for C. This paper examines the usefulness and comprehensibility of the MISRA C:2012 guidelines in an eye tracking study. There, subjects encounter non-compliant code in four different code review settings: with no additional reference, with an actual MISRA C guideline, with a case-specific interpretation of a MISRA C guideline, and with a compliant version of the code. The data collected was analyzed not only in terms of the four presentation styles, but also by dividing the subjects into experience levels based on their semesters of study or years of work experience. Regarding the difference between actual and interpreted guidelines, we found that for interpreted guidelines the error detection rate is higher whereas the duration and frequency of visits to the guideline itself are mainly lower. This suggest that the actual guidelines are less useful and more difficult to understand. The former is contradicted by the subjects’ opinions: when surveyed, they rated the usefulness of the actual guidelines higher. Y1 - 2023 SN - 978-1-4503-9956-2 U6 - https://doi.org/10.1145/3593663.3593671 SP - 130 EP - 137 PB - ACM ER - TY - CHAP A1 - Grabinger, Lisa A1 - Hauser, Florian A1 - Mottok, Jürgen T1 - Evaluating Graph-based Modeling Languages T2 - Proceedings of the 5th European Conference on Software Engineering Education, Seeon/Germany, June 19 - 21, 2023 N2 - As humans, we tend to use models to describe reality. Modeling languages provide the formal frameworks for creating such models. Usually, the graphical design of individual model elements is based on subjective decisions; their suitability is determined at most by the prevalence of the modeling language. With other words: there is no objective way to compare different designs of model elements. The present paper addresses this issue: it introduces a systematic approach for evaluating the elements of graph-based modeling languages comprising 14 criteria – derived from standards, usability analyses, or the design theories ‘Physics of Notations’ and ‘Cognitive Dimensions of Notations’. The criteria come with measurement procedures and evaluation schemes based on reasoning, eye tracking, and questioning. The developed approach is demonstrated with a specific use case: three distinct sets of node elements for causal graphs are evaluated in an eye tracking study with 41 subjects. Y1 - 2023 SN - 978-1-4503-9956-2 U6 - https://doi.org/10.1145/3593663.3593664 SP - 120 EP - 129 PB - ACM ER - TY - CHAP A1 - Bittner, Dominik A1 - Hauser, Florian A1 - Nadimpalli, Vamsi Krishna A1 - Grabinger, Lisa A1 - Staufer, Susanne A1 - Mottok, Jürgen T1 - Towards Eye Tracking based Learning Style Identification T2 - Proceedings of the 5th European Conference on Software Engineering Education, Seeon/Germany, June 19 - 21, 2023 N2 - The dropout rate at universities has been very high for years. Thereby, the inexperience and lack of knowledge of students in dealing with individual learning paths in various courses of study plays a decisive role. Adaptive learning management systems are suitable countermeasures, in which learners’ learning styles are classified using questionnaires or computationally intensive algorithms before a learning path is suggested accordingly. In this paper, a study design for student learning style classification using eye tracking is presented. Furthermore, qualitative and quantitative analyses clarify certain relationships between students’ eye movements and learning styles. With the help of classification based on eye tracking, the filling out of questionnaires or the integration of computationally or cost-intensive algorithms can be made redundant in the future. Y1 - 2023 SN - 978-1-4503-9956-2 U6 - https://doi.org/10.1145/3593663.3593680 SP - 138 EP - 147 PB - ACM ER - TY - CHAP A1 - Hauser, Florian A1 - Grabinger, Lisa A1 - Mottok, Jürgen T1 - Something Short Gets Even Shorter: Adapting the LIST-K for the Use in an Online Learning Management System T2 - Proceedings of the 5th European Conference on Software Engineering Education, Seeon/Germany, June 19 - 21, 2023 N2 - This study examines how Klingsieck’s LIST-K questionnaire [22] can be shortened and adapted to the requirements of an online learning management system. In a study with 213 participants, the questionnaire is subjected to an exploitative factor analysis. In a next step, the results are evaluated in terms of their reliability. This process creates a modified factor structure for the LIST-K, comprising a total of eight factors. The reliability of the modified questionnaire is at an α of .770. The shortened version of the LIST-K questionnaire is currently being used on an experimental basis in different courses. Y1 - 2023 SN - 978-1-4503-9956-2 U6 - https://doi.org/10.1145/3593663.3593684 SP - 65 EP - 72 PB - ACM ER - TY - JOUR A1 - De, Sangita A1 - Premek, Brada A1 - Mottok, Jürgen T1 - Derivation of Optimized Threshold of Semantic Alignment Metrics for Intepretation of Interoperability and Reusability of Cross-enterprise Vehicle Service Interface Models JF - Informatica N2 - Over the past decade, cars have turned gradually into real cyber physical systems. The collaboration of services between the service-oriented, cross-enterprise vehicle application frameworks has increased to generate novel, smart and complicated vehicle services. Consequently, from an interoperability perspective, semantically mapping of vehicle service component’s interface ontological models emerged as a big research interest in automotive application domain that manipulates several cross-enterprise synergy knowledge applications frameworks. The ontological metamodeling lays the foundation for building semantic bridge and exploring semantic associations between service components’ interface models based on the domain knowledge for semantic interoperability. Also, several semantic quality metrics has been defined over time for the vehicle service interface ontological metamodels. The empirically evaluated values of these metrics can be used to assess progress in cross-enterprise interoperability between the service and the clients’ APIs ontological models in vehicle domain. Despite potential benefits of semantic alignment quality metrics, the effective use of these metrics for vehicle service interface ontologies have proven elusive. Yes, such metrics can be used successfully for quantification, but then they mostly fail to provide adequate annotations in subsequent decision-making in the direction of semantic interoperability and reusability. The effective use of ontology semantic alignment quality metrics is basically hindered in the absence of the meaningful thresholds. In fact, the absence of an effective and meaningful threshold for the semantic similarity measure between various vehicle service interface ontological metamodels, motivates this research work which not only proposes a design approach to an optimized threshold for the semantic similarity metrics but also applies this threshold on few defined semantic alignment quality metrics. This paper also uses a real-world vehicle domain industrial case study to illustrate the design approach. KW - interface KW - automotive services KW - semantic KW - metrics KW - optimized threshold KW - framework KW - metamodels KW - ontologies Y1 - 2023 U6 - https://doi.org/10.31449/inf.v47i7.4739 SN - 0350-5596 VL - 47 IS - 7 PB - Slovenian Society Informatika ER - TY - CHAP A1 - Hauser, Florian A1 - Grabinger, Lisa A1 - Mottok, Jürgen A1 - Jahn, Sabrina A1 - Nadimpalli, Vamsi Krishna T1 - The Expert’s View: Eye Movement Modeling Examples in Software Engineering Education T2 - Proceedings of the 5th European Conference on Software Engineering Education, Seeon/Germany, June 19 - 21, 2023 N2 - This study investigates the impact of eye movement modeling examples in Software Engineering education. Software Engineering is a highly visual domain. The daily tasks of a software engineer (e.g., formulating requirements, creating UML diagrams, or conducting a code review) require in many cases the use of certain visual strategies. Although these strategies can be found for experts, it has been observed in different eye tracking studies that students have difficulties in learning and applying them. To familiarize students with these visual strategies and to provide them with a better understanding for the cognitive processes involved, a total of seven eye movement modeling examples was created. The seven eye movement modeling examples cover relevant parts of an introductory Software Engineering lecture; they are focused on typical situations in which visual strategies are applied. The results of a questionnaire-based evaluation shows that students consider the eye movement modeling examples as useful, feel supported in their learning process, and would like to see more use of them in the Software Engineering lecture. Furthermore, the students suggested that eye movement modeling examples should also be used in other lectures. Y1 - 2023 SN - 978-1-4503-9956-2 U6 - https://doi.org/10.1145/3593663.3593683 SP - 148 EP - 152 PB - ACM ER - TY - CHAP A1 - Nadimpalli, Vamsi Krishna A1 - Hauser, Florian A1 - Bittner, Dominik A1 - Grabinger, Lisa A1 - Staufer, Susanne A1 - Mottok, Jürgen ED - Mottok, Jürgen T1 - Systematic Literature Review for the Use of AI Based Techniques in Adaptive Learning Management Systems T2 - Proceedings of the 5th European Conference on Software Engineering Education, Seeon/Germany, June 19 - 21, 2023 N2 - Nowadays, learning management systems are widely employed in all educational institutions to instruct students as a result of the increasing in online usage. Today’s learning management systems provide learning paths without personalizing them to the characteristics of the learner. Therefore, research these days is concentrated on employing AI-based strategies to personalize the systems. However, there are many different AI algorithms, making it challenging to determine which ones are most suited for taking into account the many different features of learner data and learning contents. This paper conducts a systematic literature review in order to discuss the AI-based methods that are frequently used to identify learner characteristics, organize the learning contents, recommend learning paths, and highlight their advantages and disadvantages. Y1 - 2023 SN - 978-1-4503-9956-2 U6 - https://doi.org/10.1145/3593663.3593681 SP - 83 EP - 92 PB - Association for Computing Machinery CY - New York ER - TY - CHAP A1 - Bugert, Flemming A1 - Grabinger, Lisa A1 - Bittner, Dominik A1 - Hauser, Florian A1 - Nadimpalli, Vamsi Krishna A1 - Staufer, Susanne A1 - Mottok, Jürgen T1 - Towards Learning Style Prediction based on Personality T2 - Proceedings of the 5th European Conference on Software Engineering Education, Seeon/Germany, June 19 - 21, 2023 N2 - This paper assesses the relation between personality, demographics, and learning style. Hence, data is collected from 200 participants using 1) the BFI-10 to obtain the participant’s expression of personality traits according to the five-factor model, 2) the ILS to determine the participant’s learning style according to Felder and Silverman, and 3) a demographic questionnaire. From the obtained data, we train and evaluate a Bayesian network. Using Bayesian statistics, we show that age and gender slightly influence personality and that demographics as well as personality have at least a minor effect on learning styles. We also discuss the limitations and future work of the presented approach. Y1 - 2023 SN - 978-1-4503-9956-2 U6 - https://doi.org/10.1145/3593663.3593682 SP - 48 EP - 55 PB - ACM ER - TY - CHAP A1 - Bittner, Dominik A1 - Hendricks, Ricky-Ricardo A1 - Horn, Luca A1 - Mottok, Jürgen T1 - In-depth Benchmarking of Transfer Learning Techniques for Improved Bottle Recognition T2 - 2023 IEEE 13th International Conference on Pattern Recognition Systems (ICPRS), Guayaquil, Ecuador, 04-07 July 2023 N2 - An immense diversity in bottle types requires high accuracy during sorting for recycling purposes by breweries. This extremely complex and time-consuming procedure can result in enormous additional costs for them. This paper presents transfer learning-based algorithms for classifying beer bottle brands using camera images, applicable in individual sorting solutions for different use cases. The problem is tackled using customised EfficientNet, InceptionResNet and VGG models along with an augmented dataset. In addition, a detailed analysis of different model and parameter combinations is performed, enabling tailor-made technologies for specific conditions and resource limitations. In accompanying validations and subsequent tests, a test accuracy of 100% in the recognition of beer brands could be achieved, proving the proposed method fully contributes to the solution of the problem. KW - Analytical models KW - Costs KW - Transfer learning KW - Benchmark testing KW - Cameras KW - Pattern recognition KW - Recycling Y1 - 2023 SN - 979-8-3503-3337-4 U6 - https://doi.org/10.1109/ICPRS58416.2023.10178995 SP - 1 EP - 6 PB - IEEE ER - TY - JOUR A1 - Maier, Robert A1 - Grabinger, Lisa A1 - Urlhart, David A1 - Mottok, Jürgen T1 - Causal Models to Support Scenario-Based Testing of ADAS JF - IEEE Transactions on Intelligent Transportation Systems N2 - In modern vehicles, system complexity and technical capabilities are constantly growing. As a result, manufacturers and regulators are both increasingly challenged to ensure the reliability, safety, and intended behavior of these systems. With current methodologies, it is difficult to address the various interactions between vehicle components and environmental factors. However, model-based engineering offers a solution by allowing to abstract reality and enhancing communication among engineers and stakeholders. Applying this method requires a model format that is machine-processable, human-understandable, and mathematically sound. In addition, the model format needs to support probabilistic reasoning to account for incomplete data and knowledge about a problem domain. We propose structural causal models as a suitable framework for addressing these demands. In this article, we show how to combine data from different sources into an inferable causal model for an advanced driver-assistance system. We then consider the developed causal model for scenario-based testing to illustrate how a model-based approach can improve industrial system development processes. We conclude this paper by discussing the ongoing challenges to our approach and provide pointers for future work. KW - automated driving systems KW - Automation KW - Bayesian networks KW - Causal inference KW - Data models KW - ISO Standards KW - model-based testing KW - Safety KW - Task analysis KW - Testing KW - Vehicles Y1 - 2023 U6 - https://doi.org/10.1109/TITS.2023.3317475 SN - 1524-9050 SP - 1 EP - 17 PB - IEEE ER - TY - CHAP A1 - Unold, Heiko ED - Dölling, Hanna ED - Schäfle, Claudia ED - Kürsten, Susanne ED - Hunger, Marianne ED - Hirtt, Jim ED - Riegler, Peter T1 - Analog Discovery: Das Elektrotechnik-Labor im Hörsaal. Zwei Experimente für die Grundlagen der Elektrotechnik T2 - TAGUNGSBAND MINT SYMPOSIUM 2023 - Lehre gemeinsam gestalten, Lehre erforschen, Wissen teilen N2 - Anhand zweier Beispiele wird ein interaktives System vorgestellt, mit welchem Live-Messungen an elektronischen Bauteilen und Schaltungen im Hörsaal durchgeführt werden können. Das System basiert auf dem USB-Messgerät „Analog Discovery 2“ der Firma Digilent, erweitert um eine Adapterplatine mit Steckbrett und eine Webcam. Zunächst werden drei Aspekte erläutert, in welchen ein solches System positive Auswirkungen auf den Kompetenzerwerb haben kann: Praxisbezug, Aktivierung und Vernetzung. Anschließend werden die zwei Beispiele ausgeführt. In Beispiel 1 wird die persönliche Alltagserfahrung mit Akkus über interaktive Clicker-Fragen und begleitende Messungen mit dem Modell der linearen Quelle verknüpft. Die Studierenden lernen, oberflächliche Lösungen wie die Messung der Leerlaufspannung zu hinterfragen und das Verhalten realer Quellen anhand der gemessenen I-U-Kennlinien zu verstehen. Beispiel 2 zeigt kurz die Möglichkeiten auf, den abstrakten Formalismus der komplexen Wechselstromrechnung am Beispiel des Serienschwingkreises im Zeit- und Frequenzbereich messtechnisch erlebbar zu machen. KW - Elektrotechnik KW - Experimentiersysten KW - Didaktik Y1 - 2023 UR - https://didaktikzentrum.de/Tagungsband/MINT-Symposium-2023 SN - 1612-4537 VL - DiNa Sonderausgabe SP - 192 EP - 198 CY - München ER - TY - CHAP A1 - Nadimpalli, Vamsi Krishna A1 - Bugert, Flemmimg A1 - Bittner, Dominik A1 - Hauser, Florian A1 - Grabinger, Lisa A1 - Staufer, Susanne A1 - Mottok, Jürgen ED - Gómez Chova, Luis ED - González Martínez, Chelo ED - Lees, Joanna T1 - Towards personalized learning paths in adaptive learning management systems: bayesian modelling of psychological theories T2 - Proceedings of the 16th annual International Conference of Education, Research and Innovation (ICERI 2023), Seville, Spain, 11/13/2023 - 11/14/2023 N2 - In educational research, non-personalized learning content increases learners' cognitive load, causing them to lower their performance and sometimes drop out of the course. Personalizing learning content with learners’ unique characteristics, like learning styles, personality traits, and learning strategies, is being suggested to improve learners’ success. Several theories exist for assessing learners’ unique characteristics. By the end of 2020, 71 learning style theories have been formulated, and research has shown that combining multiple learning style theories to recommend learning paths yields better results. As of the end of 2022, there is no single research that demonstrates a relationship between the Index of Learning Styles (ILS) based Felder-Silverman learning style model (FSLSM) dimensions, Big Five (BFI-10) based personality traits, and the Learning strategies in studying (LIST-K) based learning strategies factors for personalizing learning content. In this paper, an innovative approach is proposed to estimate the relationship between these theories and map the corresponding learning elements to create personalized learning paths. Respective questionnaires were distributed to 297 higher education students for data collection. A three-step approach was formulated to estimate the relationship between the models. First, a literature search was conducted to find existing studies. Then, an expert interview was carried out with a group of one software engineering education research professor, three doctoral students, and two master’s students. Finally, the correlations between the students' questionnaire responses were calculated. To achieve this, a Bayesian Network was built with expert knowledge from the three-step approach, and the weights were learned from collected data. The probability of individual FSLSM learning style dimensions was estimated for a new test sample. Based on the literature, the learning elements were mapped to the respective FSLSM learning style dimensions and were initiated as learning paths to the learners. The next steps are proposed to extend this framework and dynamically recommend learning paths in real time. In addition, the individual levels of learning style dimensions, personality traits, and learning strategies can be considered to improve the recommendations. Further, using probabilities for mapping learning elements to learning styles can increase the chance of initiating multiple learning paths for an individual learner. Y1 - 2023 U6 - https://doi.org/10.21125/iceri.2023.1144 SP - 4593 EP - 4603 PB - IATED ER - TY - CHAP A1 - Staufer, Susanne A1 - Hauser, Florian A1 - Grabinger, Lisa A1 - Bittner, Dominik A1 - Nadimpalli, Vamsi Krishna A1 - Mottok, Jürgen ED - Gómez Chova, Luis ED - González Martínez, Chelo ED - Lees, Joanna T1 - Learning elements in online learning management systems T2 - Proceedings of the 16th annual International Conference of Education, Research and Innovation (ICERI 2023), Seville, Spain, 11/13/2023 - 11/14/2023 Y1 - 2023 U6 - https://doi.org/10.21125/iceri.2023.0815 SP - 3121 EP - 3130 PB - IATED ER - TY - CHAP A1 - Franke, Ariane ED - Uhl, Christian ED - Walter, Michael ED - Stiehl, Annika T1 - Electricity load forecasting for industrial microgrid and load management T2 - Applied Research Conference 2022 Conference Proceedings: 4th July 2022, University of Applied Sciences Ansbach (Onsite Conference) N2 - As more energy systems from renewable sources and the electricity market becomes more volatile, new solutions to ensure the security of supply are tested. Microgrids offer a possibility to prevent construction downtime. In order to use the energy sources and storage facilities of the microgrid effectively, load forecasting algorithms are essential. Thus, in this study a short term load forecasting model for a construction company is designed, that will be used for managing a microgrid as well as the general load consumption. This paper proposes the use of the XGBoost algorithm for the 36-hour forecast including predictors based on past measurements as well as information extracted from the timestamp. Moreover, it is shown that including load profiles attained by conventional methods has the potential to improve the accuracy of the model. KW - load forecast KW - XGBoost KW - load profile Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-68231 SP - 405 EP - 409 PB - Hochschule Ansbach CY - Ansbach ER - TY - JOUR A1 - Johnson, Ebin M. A1 - Anwer, Shakil A1 - Xu, Yongchao A1 - Fuhrmann, Thomas A1 - Mandl, Roland T1 - Contactless Low-Cost Position Sensor using a D-Shaped Polymer Optical Fiber JF - IEEE Sensors Journal N2 - This article describes a contactless fiber-optic position sensor. It comprises a Polymer Optical Fiber that is grinded to form a D-shaped cross-section with an exposed fiber core. This sensor has two photodiodes at both fiber ends to measure the emitted light intensity. Light is coupled using a red LED at the side face into the exposed core of the fiber at a defined position. The position of the LED at the length of the fiber is measured by calculating the optical power quotient measured by both photodiodes. To test this sensor, Polymer Optical Fibers with different side surface roughness are produced and qualified. Measurements show that the optical power quotient is reproducible and nearly linear over the length of the fiber. It is also seen that the fiber attenuation increases when grinding the fiber side-face with rougher sandpaper. Position measurements show an absolute position error of this sensor in the range of a few millimeters. Microscope images show surface defects along the polished side face of the fiber that are expected to lead to a nonuniform attenuation along the fiber and cause the position errors. Overall, it is proven that this sensor principle works as a contactless low-cost position sensor for short distances with an absolute position standard deviation error lower than 1 mm. KW - Optical fibers KW - Optical fiber sensors KW - Sensors KW - Photodiodes KW - Optical surface waves KW - Surface roughness KW - Rough surfaces KW - Fiber-optic sensor KW - Position measurement KW - Polymer Optical Fiber Y1 - 2024 U6 - https://doi.org/10.1109/JSEN.2023.3348127 PB - IEEE ER - TY - CHAP A1 - Bauer, Franz A1 - Gawlik, Julia A1 - Sterner, Michael A1 - Hamacher, Thomas ED - Ausfelder, Florian ED - Du Tran, Dinh T1 - Übergreifende Energiesystemmodellierung T2 - Optionen für ein nachhaltiges Energiesystem mit Power-to-X-Technologien: Transformation - Anwendungen – Potentiale. 4. Roadmap des Kopernikus-Projektes P2X, Phase II Y1 - 2022 UR - https://www.kopernikus-projekte.de/lw_resource/datapool/systemfiles/elements/files/EC7C18F68BCE7C0DE0537E695E86F60F/live/document/221025_DEC_P2X4_V08_Web.pdf SN - 978-3-89746-238-0 SP - 17 EP - 35 PB - DECHEMA Gesellschaft für Chemische Technik und Biotechnologie e.V. CY - Frankfurt a.M. ER - TY - CHAP A1 - Bauer, Franz A1 - Gawlik, Julia A1 - Sterner, Michael A1 - Hamacher, Thomas ED - Ausfelder, Florian ED - Dura, Hanna T1 - Übergreifende Energiesystemmodellierung T2 - Optionen für ein nachhaltiges Energiesystem mit Power-to-X-Technologien: Transformation - Anwendungen – Potentiale. 3. Roadmap des Kopernikus-Projektes P2X, Phase II Y1 - 2021 UR - https://www.kopernikus-projekte.de/lw_resource/datapool/systemfiles/elements/files/CBE2878A53D522EEE0537E695E868061/live/document/DEC_P2X_II_V06_Online_small.pdf SN - 978-3-89746-236-6 SP - 19 EP - 33 PB - DECHEMA Gesellschaft für Chemische Technik und Biotechnologie e.V. CY - Frankfurt a.M. ER - TY - JOUR A1 - Fuhrmann, Thomas A1 - Mandl, Roland A1 - Shamonin (Chamonine), Mikhail T1 - Analysis of learning improvement on changing lab course from single experiments to projects JF - International Journal of Electrical Engineering Education N2 - During recent years, there has been a trend to replace traditional lab courses by project-based learning activities. However, there is currently little scientific evidence for educational improvements through such changes. Some years ago, a lab course on electrical measurements in our bachelor Electrical Engineering and Information Technology was modified from single experiments to projects. This change led to a significant increase in the necessary manpower and lab costs. To justify these higher efforts, it is important to investigate if the learning success increased. We carried out the surveys and collected the statistical data from the students who attended this course. In order to see if the students appreciated this lab course and if there was an objective increase of the students' knowledge, these results were evaluated. Evaluation of the grades in the lecture and lab courses shows that the increase of the students' theoretical and practical knowledge is statistically significant. KW - Electrical engineering education KW - project-based learning KW - student experiments Y1 - 2015 U6 - https://doi.org/10.1177/0020720915583863 VL - 52 IS - 4 SP - 287 EP - 297 PB - SAGE ER - TY - RPRT A1 - Lermer, Valentin josef A1 - Heiß, Simon A1 - Gierl, Philipp A1 - Rappl, Veronika A1 - Ardaya-Lieb, Samuel A1 - Möhring, Christoph A1 - Solisch, Matthias A1 - Solisch, Tobias A1 - Garschhammer, Kilian A1 - Kammerl, Andreas A1 - Kolb, Moritz A1 - Hohenadler, Franz A1 - Reber, Luis A1 - Hartwig, Anton A1 - Schaller, Jonas A1 - Meyer, Katrin A1 - Lausser, Florian ED - Meier, Hans ED - Niemetz, Michael ED - Fuhrmann, Thomas ED - Reindl, Andrea T1 - FMS-BERICHTE SOMMERSEMESTER 2022 BT - Seminar zu aktuellen Themen der Elektro- und Informationstechnik N2 - Dieser Bericht entstand im Rahmen der Lehrveranstaltung „Forschungsmethoden und Seminar (FMS)“ im Sommersemester 2022 auf Initiative der Studierenden des Masterstudiengangs „Elektro- und Informationstechnik (MEI)“. Diese Lehrveranstaltung hat das Ziel, systematisch an das wissenschaftliche Arbeiten, speziell die Wissenschaftskommunikation, heranzuführen. Daher war geeignete Literatur zu einem individuellen Thema zu recherchieren, Veröffentlichungen auf ihre Relevanz hin zu beurteilen und letztendlich eine eigene Ausarbeitung basierend auf der Literaturrecherche zu erarbeiten und diese in einem Vortrag zu präsentieren. Parallel dazu erfolgte im Theorieteil die entsprechende Hinführung zu den verschiedenen Elementen der Wissenschaftskommunikation: • Bedeutung der Wissenschaftskommunikation für die Arbeit der Ingenieure in Forschung und Entwicklung • Literaturrecherche, Suchmaschinen, Sichtung und Analyse vorhandener Publikationen, Bewertung der Qualität aufgefundener Fachliteratur, Auswahl geeigneter Materialien für die eigene Arbeit • Aufbereitung und Darstellung der recherchierten technischer Inhalte in Form einer seitenanzahlbegrenzten wissenschaftlichen Ausarbeitung • Einhalten formaler Randbedingungen bzgl. Strukturierung, einschl. Bildnachweise und Zitationsstile • Peer-review-Prozess bei wertschätzender Beurteilung der Leistung anderer • Publikumsangepasstes Aufbereiten komplexer fachlicher Inhalte mit hochschulöffentlicher Präsentation der Ergebnisse • Führen mündlicher wissenschaftlicher Diskurse Nachdem die Masterstudierenden in der Regel über noch keine eigene wissenschaftliche Forschungserfahrung bzw. -inhalte verfügen, lag der wählbare Schwerpunkt der Literatursuche auf der Bearbeitung von vorgegeben aktuellen technischen oder gesellschaftspolitischen Forschungsthemen. KW - Literaturrecherche KW - Energietechnik KW - Informationstechnik KW - Elektrotechnik KW - Angewandte Wissenschaften Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-54685 CY - Regensburg ER - TY - RPRT A1 - Bräuer, Armin A1 - Zwick, Christian A1 - Reif, Florian A1 - Kick, Andreas A1 - Albrecht, Manuel A1 - Mayer, Christoph A1 - Baddour, Mahmoud A1 - Stober, Lukas A1 - Kirmeier, Andreas A1 - Griesbeck, Sebastian A1 - Reger, Simon ED - Meier, Hans ED - Niemetz, Michael ED - Fuhrmann, Thomas ED - Reindl, Andrea T1 - FMS-BERICHTE WINTERSEMESTER 2021/2022 BT - Seminar zu aktuellen Themen der Elektro- und Informationstechnik N2 - Dieser Bericht entstand im Rahmen der Lehrveranstaltung „Forschungsmethoden und Seminar (FMS)“ im Wintersemester 2021/22 auf Initiative der Studierenden des Masterstudiengangs „Elektro- und Informationstechnik (MEI)“. Diese Lehrveranstaltung hat das Ziel, systematisch an das wissenschaftliche Arbeiten, speziell die Wissenschaftskommunikation, heranzuführen. Daher war geeignete Literatur zu einem individuellen Thema zu recherchieren, Veröffentlichungen auf ihre Relevanz hin zu beurteilen und letztendlich eine eigene Ausarbeitung basierend auf der Literaturrecherche zu erarbeiten und diese in einem Vortrag zu präsentieren. Parallel dazu erfolgte im Theorieteil die entsprechende Hinführung zu den verschiedenen Elementen der Wissenschaftskommunikation: • Bedeutung der Wissenschaftskommunikation für die Arbeit der Ingenieure in Forschung und Entwicklung • Literaturrecherche, Suchmaschinen, Sichtung und Analyse vorhandener Publikationen, Bewertung der Qualität aufgefundener Fachliteratur, Auswahl geeigneter Materialien für die eigene Arbeit • Aufbereitung und Darstellung der recherchierten technischer Inhalte in Form einer seitenanzahlbegrenzten wissenschaftlichen Ausarbeitung • Einhalten formaler Randbedingungen bzgl. Strukturierung, einschl. Bildnachweise und Zitationsstile • Peer-review-Prozess bei wertschätzender Beurteilung der Leistung anderer • Publikumsangepasstes Aufbereiten komplexer fachlicher Inhalte mit hochschulöffentlicher Präsentation der Ergebnisse • Führen mündlicher wissenschaftlicher Diskurse Nachdem die Masterstudierenden in der Regel über noch keine eigene wissenschaftliche Forschungserfahrung bzw. -inhalte verfügen, lag der wählbare Schwerpunkt der Literatursuche auf der Bearbeitung von vorgegeben aktuellen technischen oder gesellschaftspolitischen Forschungsthemen. KW - Elektrotechnik KW - Informationstechnik KW - Angewandte Wissenschaften KW - Literaturrecherche KW - Energietechnik Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-54371 CY - Regensburg ER - TY - RPRT A1 - Geiss, Florian A1 - Liedl, Lucia A1 - Thalhammer, Florian A1 - Mauderer, Johannes A1 - Meier, Maximilian A1 - Geitner, Florian A1 - Bindl, Jakob A1 - Belz, Reinhold ED - Meier, Hans ED - Niemetz, Michael ED - Fuhrmann, Thomas ED - Reindl, Andrea T1 - FMS-BERICHTE WINTERSEMESTER 2022/23 BT - Seminar zu aktuellen Themen der Elektro- und Informationstechnik N2 - Dieser Bericht entstand auf Initiative der Studierenden des Masterstudiengangs „Elektro- und Informationstechnik (MEI)“, die an der Pflichtlehrveranstaltung „Forschungsmethoden und Seminar (FMS)“ im Wintersemester 2022/23 teilnahmen. Diese Lehrveranstaltung hat das Ziel, systematisch an das wissenschaftliche Arbeiten, speziell die Wissenschaftskommunikation, heranzuführen. Daher war geeignete Literatur zu einem individuellen Thema zu recherchieren, Veröffentlichungen auf ihre Relevanz hin zu beurteilen und letztendlich eine eigene Ausarbeitung basierend auf der Literaturrecherche zu erarbeiten und diese in einem Vortrag zu präsentieren. Parallel dazu erfolgte im Theorieteil die entsprechende Hinführung zu den verschiedenen Elementen der Wissenschaftskommunikation: • Bedeutung der Wissenschaftskommunikation für die Arbeit der Ingenieure in Forschung und Entwicklung • Literaturrecherche, Suchmaschinen, Sichtung und Analyse vorhandener Publikationen, Bewertung der Qualität aufgefundener Fachliteratur, Auswahl geeigneter Materialien für die eigene Arbeit • Aufbereitung und Darstellung der recherchierten technischer Inhalte in Form einer seitenanzahlbegrenzten wissenschaftlichen Ausarbeitung • Einhalten formaler Randbedingungen bzgl. Strukturierung, einschl. Bildnachweise und Zitationsstile • Peer-review-Prozess bei wertschätzender Beurteilung der Leistung anderer • Publikumsangepasstes Aufbereiten komplexer fachlicher Inhalte mit hochschulöffentlicher Präsentation der Ergebnisse • Führen mündlicher wissenschaftlicher Diskurse Nachdem die Masterstudierenden in der Regel über noch keine eigene wissenschaftliche Forschungserfahrung bzw. -inhalte verfügen, lag der wählbare Schwerpunkt der Literatursuche auf der Bearbeitung von vorgegeben aktuellen technischen oder gesellschaftspolitischen Forschungsthemen. Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-60324 PB - Ostbayerische Hochschule Regensburg CY - Regensburg ER - TY - JOUR T1 - Energieforschung BT - geförderte Projekte 2017 bis 2019 N2 - Über uns Das Regensburg Center of Energy and Resources (RCER) bündelt seit 2012 die Aktivitäten der Ostbayerischen Technischen Hochschule Regensburg (OTH Regensburg) und der regionalen Wirtschaftsunternehmen auf dem Strategiefeld „Energie und Ressourcen“. Mission: Energieforschung: vernetzen, voranbringen, vermitteln Das RCER fördert die Vernetzung verschiedener Disziplinen der Energieforschung innerhalb der OTH Regensburg und mit externen Partnern (Firmen, Förderträgern, Forschungsinstitutionen, öffentlichen Einrichtungen). Das RCER ist Ihr Partner beim Voranbringen von Kooperationen und Forschungsvorhaben durch Unterstützung in der Antragsphase, bei der Einwerbung von Projektmitteln und Projektbegleitung im Energiebereich. Das RCER steht für die Vermittlung von Know-how, Basiswissen, aktuellen Fragen und den Technologietransfer rund um das Thema Energie zwischen Wissenschaft, Wirtschaft, Gesellschaft und Politik. Vision Wir sind Ihr erster Ansprechpartner und Motor für innovative Energieforschung. Werte Verlässlichkeit, Kompetenz, Verantwortungsbewusstsein.Regional verwurzelt und weltoffen Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-65439 PB - OTH Regensburg ET - Ausgabe 2020 ER - TY - JOUR T1 - Energieforschung BT - geförderte Projekte 2013 bis 2016; Netzwerke und Tendenzen: Ziele und Ausrichtung des RCER; Energie und Ressourcen: Projekte stellen sich vor; Wissenstransfer: Energiekongress und Infotage N2 - Das Regensburg Center of Energy and Resources (RCER) bündelt seit 2012 die Aktivitäten der Ostbayerischen Technischen Hochschule Regensburg (OTH Regensburg) und der regionalen Wirtschaftsunternehmen auf dem Strategiefeld „Energie und Ressourcen“. Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-66948 PB - OTH Regensburg ET - Ausgabe 2016 ER - TY - JOUR A1 - Glavan, Gašper A1 - Belyaeva, Inna A1 - Shamonin (Chamonine), Mikhail T1 - Transient Response of Macroscopic Deformation of Magnetoactive Elastomeric Cylinders in Uniform Magnetic Fields JF - Polymers N2 - Significant deformations of bodies made from compliant magnetoactive elastomers (MAE) in magnetic fields make these materials promising for applications in magnetically controlled actuators for soft robotics. Reported experimental research in this context was devoted to the behaviour in the quasi-static magnetic field, but the transient dynamics are of great practical importance. This paper presents an experimental study of the transient response of apparent longitudinal and transverse strains of a family of isotropic and anisotropic MAE cylinders with six different aspect ratios in time-varying uniform magnetic fields. The time dependence of the magnetic field has a trapezoidal form, where the rate of both legs is varied between 52 and 757 kA/(s·m) and the maximum magnetic field takes three values between 153 and 505 kA/m. It is proposed to introduce four characteristic times: two for the delay of the transient response during increasing and decreasing magnetic field, as well as two for rise and fall times. To facilitate the comparison between different magnetic field rates, these characteristic times are further normalized on the rise time of the magnetic field ramp. The dependence of the normalized characteristic times on the aspect ratio, the magnetic field slew rate, maximum magnetic field values, initial internal structure (isotropic versus anisotropic specimens) and weight fraction of the soft-magnetic filler are obtained and discussed in detail. The normalized magnetostrictive hysteresis loop is introduced, and used to explain why the normalized delay times vary with changing experimental parameters. KW - magnetoactive elastomer KW - magnetorheological elastomer KW - macroscopic deformation KW - magnetostriction KW - time-varying magnetic field Y1 - 2024 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-71067 SN - 2073-4360 N1 - Corresponding author der OTH Regensburg: Gašper Glavan VL - 16 IS - 5, Special Issue Magnetic Polymer Composites: Design and Application II PB - MDPI CY - Basel, Schweiz ER - TY - JOUR A1 - Deubzer, Michael A1 - Mottok, Jürgen A1 - Bärwald, Andreas T1 - Dependability-Betrachtung von Multicore-Scheduling JF - HANSER Automotive N2 - Der Embedded Markt stellt sich auf eine neue Herausforderung ein: denUmstieg von Singlecore- auf Multicore-Prozessorsysteme. Dabei soll dieUmsetzung der Norm ISO 26262 die Funktionale Sicherheit der elektri-schen und elektronischen Systeme im Kraftfahrzeug gewährleisten. In diesem Beitrag betrachten die Hochschule Regensburg und die TÜV SüdAutomotive GmbH das Scheduling eines Echtzeitsystems als ein sicher-heitsrelevantes Sub-System. Y1 - 2010 UR - https://res.cloudinary.com/sternwald-systems/raw/upload/v1/hugoprd/ARTIKEL_ATTACH/00207DD4_0669BA3F5B24/4b2124fb030a4d3d5a42a83aaec4bddadebe3077/AM_2010_11_Dependability-Betrachtung-von-Multicore-Scheduling.pdf IS - 11 SP - 24 EP - 27 ER - TY - CHAP A1 - Renner, Sebastian A1 - Pozzobon, Enrico A1 - Mottok, Jürgen ED - Meng, Weizhi T1 - A Hardware in the Loop Benchmark Suite to Evaluate NIST LWC Ciphers on Microcontrollers T2 - Information and Communications Security: 22nd International Conference, ICICS 2020, Copenhagen, Denmark, August 24-26, 2020, Proceedings N2 - The National Institute of Standards and Technology (NIST) started the standardization process for lightweight cryptography algorithms in 2018. By the end of the first round, 32 submissions have been selected as 2nd round candidates. NIST allowed designers of 2nd round submissions to provide small updates on both their specifications and implementation packages. In this work, we introduce a benchmarking framework for evaluating the performance of NIST Lightweight Cryptography (LWC) candidates on embedded platforms. We show the features and application of the framework and explain its design rationale. Moreover, we provide information on how we aim to present up-to-date performance figures throughout the NIST LWC competition. In this paper, we present an excerpt of our software benchmarking results regarding speed and memory requirements of selected ciphers. All up-to-date results, including benchmarking different test cases for multiple variants of each 2nd round algorithm on five different microcontrollers, are periodically published to a public website. While initially only the reference implementations were available, the ability of automatically testing the performance of the candidate algorithms on multiple platforms becomes especially relevant as more optimized implementations are developed. Finally, we show how the framework can be extended in different directions: support for more target platforms can be easily added, different kinds of algorithms can be tested, and other test metrics can be acquired. The focus of this paper should rather lay on the framework design and testing methodology than on the current results, especially for reference code. KW - Lightweight cryptography KW - Benchmarking KW - Embedded systems KW - RISC-V Y1 - 2020 U6 - https://doi.org/10.1007/978-3-030-61078-4_28 SP - 495 EP - 509 PB - Springer CY - Cham ER - TY - CHAP A1 - Seebauer, Stefan A1 - Jahn, Sabrina A1 - Mottok, Jürgen T1 - Learning from Escape Rooms? A Study Design Concept Measuring the Effect of a Cryptography Educational Escape Room T2 - 2020 IEEE Global Engineering Education Conference (EDUCON): 27-30 April 2020, Porto, Portugal N2 - Experts predict that more IT-Security specialists will be needed in the coming years, but in current higher education in engineering disciplines, this topic is hardly addressed. Newer learning methods such as game-based learning (GBL) are enjoying an increasing popularity as their improvement in the education of subject specific topics can be proven by a variety of studies. We chose Educational Escape Rooms (EduER) as a GBL-tool to impart IT-Security in higher education of engineers. In our Escape Room (ER), the students try to solve puzzles and riddles with learned knowledge on the emphasis of cryptography. This paper first deals with a brief introduction to GBL and EduERs, followed by the design of our ER concept, containing different tasks with focus on the topic of cryptography. The tasks cover different cryptographic methods and hash algorithms, e.g. AES, RSA, SHA3. Afterwards the experimental study is presented. The study of the EduER was carried out with students from the bachelor's program in Electrical Engineering and Information Technology at the OTH Regensburg. The participants were divided into three groups of 5 to 8 persons each. They received a briefing with important information, followed by the ER execution, a debriefing afterwards and an exam-like evaluation sheet to test their learned knowledge. Finally, first basic results are presented. Y1 - 2020 U6 - https://doi.org/10.1109/EDUCON45650.2020.9125333 SP - 1684 EP - 1685 ER - TY - CHAP A1 - Klopp, Marco A1 - Gold-Veerkamp, Carolin A1 - Abke, Jörg A1 - Borgeest, Kai A1 - Reuter, Rebecca A1 - Jahn, Sabrina A1 - Mottok, Jürgen A1 - Sedelmaier, Yvonne A1 - Lehmann, Alexander A1 - Landes, Dieter T1 - Totally Different and yet so Alike: Three Concepts to Use Scrum in Higher Education T2 - Proceedings of the 4th European Conference on Software Engineering Education (ECSEE '20): June 2020, Seeon/Bavaria, Germany N2 - Software process models are important in software projects in order to give the work of a project guidelines or a framework. However, teaching process models in higher education seems to be quite challenging. This has to do with the fact that undergraduates have no experience with projects in which process models are used. The theoretical mediation of process models is initially on a very abstract level. For this reason, we chose to combine two didactic approaches, namely problem-based learning and project work. Various traditional plan-driven process models have been expanded in courses in Software Engineering with agile process models. The Scrum Framework is the focus of consideration of this paper. Three Universities of Applied Sciences which cooperate in the EVELIN project focused on Scrum as a process model and integrated it into their teaching. Since the respective concepts of implementation differ, they should be presented and compared in this article to presents some practice approaches. The goal of this presentation of is a uniform evaluation in order to obtain insights from different perspectives. This comparison can draw conclusions for possible necessary improvements of the respective concepts. Y1 - 2020 U6 - https://doi.org/10.1145/3396802.3396817 SP - 12 EP - 21 ER - TY - CHAP A1 - Dentgen, Manuel A1 - Renner, Sebastian A1 - Mottok, Jürgen ED - Brinkmann, André ED - Karl, Wolfgang ED - Lankes, Stefan ED - Tomforde, Sven ED - Pionteck, Thilo ED - Trinitis, Carsten T1 - Equally Distributed Bus-Communication Access Rights for Inter MCU Communication Using Multimaster SPI T2 - Architecture of Computing Systems - ARCS 2020: 33rd international conference, Aachen, Germany, May 25-28, 2020, proceedings T2 - Lecture notes in computer science ; Bd. 12155 N2 - With the rising complexity and processing power of modern computer systems, the amount of MCU on a single PCB also rises. These microcontrollers often need to communicate with each other to exchange payload and control information in a bidirectional manner. Today’s well-established communication protocols in MCUs either do not fit modern transmission speed requirements or do have an inappropriate master-slave attribute, which does not allow the communication partners to have equal bus access rights. Therefore, this paper introduces an extension of the Serial Peripheral Interface (SPI) to allow an equally distributed access right for the communication interface between two microcontrollers. It simultaneously does fit modern transmission speed requirements of a common network interface, so that the message transmission does not constitute a bottleneck in data processing. Besides the protocol design, we do also provide a first prototype implementation, which constitutes a proof of concept. Y1 - 2020 U6 - https://doi.org/10.1007/978-3-030-52794-5_15 SP - 200 EP - 212 ER - TY - CHAP A1 - Reuter, Rebecca A1 - Stark, Theresa A1 - Sedelmaier, Yvonne A1 - Landes, Dieter A1 - Mottok, Jürgen A1 - Wolff, Christian T1 - Insights in Students’ Problems during UML Modeling T2 - 2020 IEEE Global Engineering Education Conference (EDUCON): Proceedings N2 - UML (Unified Modeling Language) is the current de facto as well as de jure standard (ISO/IEC 19505:2012) notation to visualize models in software development. UML provides essential guidelines and rules to visualize and understand complex software systems. This is the reason why it has become part of curricula for software engineering courses at many universities worldwide. It is well known, however, that UML is hard to grasp for novices, mainly due to its complexity. In order to tackle the problem of teaching UML to novice students appropriately, it is inevitable to understand their needs and problems much better than we do now. This paper presents empirical insights into students' problems when developing common UML diagrams. Identified problems are generalized, giving rise to a problem catalogue that is derived from our empirical findings, thus establishing a basis for addressing these problems through focused learning arrangements. KW - UML KW - UML problems KW - software engineering KW - higher education KW - visual notation Y1 - 2020 U6 - https://doi.org/10.1109/EDUCON45650.2020.9125110 SP - 592 EP - 600 ER - TY - CHAP A1 - Hauser, Florian A1 - Stark, Theresa A1 - Mottok, Jürgen A1 - Gruber, Hans A1 - Reuter, Rebecca T1 - Deliberate Practice in Programming: How is it carried out by programmers? T2 - ECSEE '20: Proceedings of the 4th European Conference on Software Engineering Education, Seeon, Germany, June 2020 N2 - This work in progress study examines through which activities programmers perform deliberate practice to improve their own skills in coding and programming. For this reason, a qualitative questionnaire was developed and conducted with a sample of 22 participants. The results indicate that programmers perform formal and informal forms of training and learning. Typically, a classical programming training in the context of a university course or for work-related reasons is a first step in the acquisition of expertise. Building on these basic skills, non-formal and informal learning activities are carried out by the learners. Especially the social interaction and the collaborative work with other programmers is of great importance in this context. The activities mentioned by the test persons fulfil the characteristics of deliberate practice and will be examined more closely in a further study. Y1 - 2020 SN - ISBN 9781450377522 U6 - https://doi.org/10.1145/3396802.3396815 SP - 42 EP - 46 ER - TY - CHAP A1 - Gruber, Hans A1 - Wolff, Christian A1 - Mottok, Jürgen A1 - Bazo, Alexander A1 - Hauser, Florian A1 - Schreistetter, Stefan T1 - Tutorial on Software Engineering Education in Co-Located Multi-User Eye-Tracking-Environments T2 - Proceedings of the 32nd IEEE Conference on Software Engineering Education and Training: Munich, November 2020 N2 - We briefly describe a tutorial on the application of Eye-Tracking technology for Software Engineering Education. We will showcase our setup of a large-scale Eye-Tracking-Classroom and its usage for real-time improvement of traditional learning scenarios in Software Engineering Education. We will focus on the integration of gaze data into modern integrated development environments (IDEs) and demonstrate a complete workflow for its usage in co-located multi-user Eye-Tracking-Environments. KW - eye-tracking KW - software engineering education KW - multi-user eye tracking KW - real-time learning scenarios Y1 - 2020 U6 - https://doi.org/10.1109/CSEET49119.2020.9206170 ER - TY - CHAP A1 - Inderwies, Tom A1 - Mottok, Jürgen T1 - Secure Software Update of a Secure Module in the Power Grid T2 - Proceedings of the Regensburg Applied Research Conference 2020 (RARC 2020), July 31st Y1 - 2020 UR - https://doi.org/10.35096/othr/pub-641 SP - 25 EP - 31 ER - TY - CHAP A1 - Mottok, Jürgen A1 - Schiller, Frank T1 - MISRA C++:2008 and safely embedded software – a safety framework for C++ T2 - Proceedings of the Automotive Safety & Security Conference Y1 - 2008 UR - http://docplayer.org/53952332-Misra-c-2008-safely-embedded-software-ses.html ER - TY - CHAP A1 - Schirdewahn, B. A1 - Mottok, Jürgen T1 - Implementierungslösungen für die Eigenentwicklung eines deterministischen, nicht preemptiven Echtzeit Betriebssystems zur Verwaltung eingebetteter Applikationen T2 - Embedded Software Engineering Kongress, Tagungsband ; 8. bis 10. Dezember 2008, Sindelfingen Y1 - 2008 SP - 141 EP - 147 ER - TY - GEN A1 - Deubzer, Michael A1 - Mottok, Jürgen A1 - Flug, Christian A1 - Zeitler, Thomas T1 - A method of performance analysis for embedded system architectures BT - Poster-Session T2 - 8. Tag der Technik am 13. Juni 2008 an der Hochschule Regensburg Y1 - 2008 ER - TY - CHAP A1 - Hobelsberger, Martin A1 - Mottok, Jürgen A1 - Dumke, Reiner T1 - Modellbasierte Sicherheitsanalysen von Software-Architekturen T2 - Embedded Software Engineering Kongress, Tagungsband ; 8. bis 10. Dezember 2008, Sindelfingen Y1 - 2008 SP - 436 EP - 443 ER - TY - JOUR A1 - Mottok, Jürgen T1 - Aktuelle Forschungsergebnisse aus dem "Laboratory for Safe and Secure Systems"(LaS3) JF - Jahresrückblick 2008 des Bayerischen IT-Sicherheitsclusters Y1 - 2008 SP - 13 EP - 15 ER - TY - JOUR A1 - Deubzer, Michael A1 - Mottok, Jürgen A1 - Hobelsberger, Martin T1 - Profiling in Embedded Real-Time Software Systemen JF - Jahresrückblick 2008 des Bayerischen IT-Sicherheitsclusters Y1 - 2008 ER - TY - JOUR A1 - Hobelsberger, Martin A1 - Mottok, Jürgen A1 - Deubzer, Michael T1 - Modellbasierte Sicherheitsanalysen von Software Architekturen JF - Jahresrückblick 2008 des Bayerischen IT-Sicherheitsclusters Y1 - 2008 ER - TY - CHAP A1 - Schmidt, P. A1 - Mottok, Jürgen T1 - "Werkstattbericht" Bioagile Softwareentwicklung T2 - Embedded Software Engineering Kongress, Tagungsband ; 8. bis 10. Dezember 2008, Sindelfingen Y1 - 2008 SP - 455 EP - 460 ER - TY - CHAP A1 - Mottok, Jürgen T1 - Safely embedded software- a safety framework for c++ T2 - Proceedings of the 1st Embedded Software Engineering Conference, 8. bis 10. Dezember 2008, Sindelfingen Y1 - 2008 SP - 444 EP - 449 ER - TY - CHAP A1 - Deubzer, Michael A1 - Margull, Ulrich A1 - Mottok, Jürgen A1 - Niemetz, Michael A1 - Wirrer, Gerhard T1 - Partitionierungs-Scheduling von Automotive Restricted Tasksystemen auf Multiprozessorplattformen T2 - Proceedings of the 2nd Embedded Software Engineering Congress, 8. bis 10. Dezember 2009, Sindelfingen Y1 - 2009 SP - 536 EP - 542 ER - TY - CHAP A1 - Studt, Reimer A1 - Mottok, Jürgen A1 - Utesch, Matthias A1 - Landes, Dieter T1 - Anwendung der Bloom´schen Taxonomie auf Lehrinhalte des Software-Engineerings T2 - Proceedings of the 2nd Embedded Software Engineering Congress, 8. bis 10. Dezember 2009, Sindelfingen Y1 - 2009 SP - 583 EP - 593 ER - TY - CHAP A1 - Krämer, Stefan A1 - Mottok, Jürgen A1 - Meier, Hans T1 - Modifikation des Taskzustandsmodells des LLREF-Schedulers auf einem Dual-Core-Prozessor T2 - Proceedings of the 2nd Embedded Software Engineering Congress, 8. bis 10. Dezember 2009, Sindelfingen Y1 - 2009 SP - 628 EP - 636 ER - TY - CHAP A1 - Mottok, Jürgen A1 - Hagel, Georg A1 - Utesch, Matthias A1 - Waldherr, Franz T1 - Konstruktivistische Didaktik - ein Rezept für eine bessere Software Engineering Ausbildung? T2 - Proceedings of the 2nd Embedded Software Engineering Congress, 8. bis 10. Dezember 2009, Sindelfingen Y1 - 2009 SP - 601 EP - 610 ER - TY - CHAP A1 - Hobelsberger, Martin A1 - Mottok, Jürgen T1 - Software Qualität – eine Glaubensfrage? Ein Überblick über Modelle der Softwarezuverlässigkeit T2 - Proceedings of the 2nd Embedded Software Engineering Congress, 8. bis 10. Dezember 2009, Sindelfingen Y1 - 2009 SP - 134 EP - 148 ER - TY - CHAP A1 - Stamatescu, G. A1 - Deubzer, Michael A1 - Mottok, Jürgen A1 - Popescu, Dan T1 - Migration overhead in multiprocessor scheduling T2 - Proceedings of the 2nd Embedded Software Engineering Congress, 8. bis 10. Dezember 2009, Sindelfingen Y1 - 2009 SP - 645 EP - 654 ER - TY - GEN A1 - Hobelsberger, Martin A1 - Mottok, Jürgen A1 - Dumke, Reiner T1 - A model based safety analysis approach for embedded system architectures T2 - Tag der Technik 2008 Y1 - 2008 ER - TY - CHAP A1 - Schmidt, P. A1 - Mottok, Jürgen T1 - Memorandum der Bioagile Software- und Systementwicklung T2 - Proceedings of the 2nd Embedded Software Engineering Congress, 8. bis 10. Dezember 2009, Sindelfingen Y1 - 2009 SP - 487 EP - 497 ER - TY - CHAP A1 - Mottok, Jürgen A1 - Schiller, Frank T1 - Safely embedded software and MISRA C++: 2008 – a safety framework for c++ T2 - Proceedings of the SAFETY@SIEMENS Conference Y1 - 2008 ER - TY - CHAP A1 - Steindl, Michael A1 - Mottok, Jürgen A1 - Meier, Hans A1 - Schiller, Frank A1 - Früchtl, M. T1 - Safeguarded Processing of Sensor Data T2 - IT-SecurityArea (IT-SA 2009) vom 13.-15. Oktober 2009, Nürnberg N2 - The spectrum of software tasks no longer includes only rare function controlling tasks for sensor actuator chains in reactive embedded systems. However, more and more responsible challenges like safety-critical scenarios are tackled. Therefore sensor data have to be safeguarded by several mechanism. An obvious and widely used approach is the use of two redundant hardware controllers, but this comes along with an additional cost, space and energy factor. Another way to fulfill certain safety properties is to implement a second diverse software channel in a single micro-controller architecture according the Safely Embedded Software (SES) approach. However, a lack of performance occurs by implementing this diverse channel for complex computations e.g. floating-point operations. This paper gives an approach for transferring the SES into a coprocessor and to migrate SES to a flexible and powerful FPGA architecture. KW - Safety embedded software KW - FPGA KW - Diverse instructions KW - Safety code weaving Y1 - 2009 UR - https://hal.archives-ouvertes.fr/hal-02268737 ER - TY - JOUR A1 - Deubzer, Michael A1 - Schiller, Frank A1 - Mottok, Jürgen A1 - Niemetz, Michael A1 - Margull, Ulrich T1 - Effizientes Multicore-Scheduling in Eingebetteten Systemen – Teil 1: Algorithmen für zuverlässige Echtzeitsysteme JF - atp - Automatisierungstechnische Praxis N2 - Eingebettete Systeme unterliegen neben den funktionalen Anforderungen besonders nicht funktionalen Qualitätsanforderungen wie Effizienz, Zuverlässigkeit und Echtzeitfähigkeit. Mit steigendem Bedarf an Rechenkapazität können bisherige Konzepte zur Leistungssteigerung von Singlecore-Systemen jedoch nicht mehr eingesetzt werden – der Umstieg auf Multicore-Systeme wird erforderlich. Im ersten Teil dieser Arbeit werden eine mögliche Prozessorarchitektur für zukünftige Automotive Multicore-Systeme und die Abstraktion der Software für diese Systeme vorgestellt. Nach einer Klassifkation von Multicore-Scheduling-Algorithmen präsentieren wir exemplarisch einen Algorithmus mit statischer Taskallokation und einen Algorithmus mit dynamischer Taskallokation. Bei beiden Algorithmen handelt es sich um eine Überführung theoretisch behandelter Algorithmen auf Automotive Systeme. Y1 - 2010 UR - https://docplayer.org/4474533-Effizienter-einsatz-von-multicore-systemen.html IS - 9 SP - 60 EP - 67 ER - TY - CHAP A1 - Deubzer, Michael A1 - Hobelsberger, Martin A1 - Mottok, Jürgen A1 - Schiller, Frank A1 - Dumke, Reiner A1 - Siegle, Markus A1 - Margull, Ulrich A1 - Niemetz, Michael A1 - Wirrer, Gerhard T1 - Modeling and Simulation of Embedded Real-Time Multi-Core Systems T2 - Proceedings of the 3rd Embedded Software Engineering Congress, 7. bis 9. Dezember 2010, Sindelfingen KW - Real-Time Systems KW - Multicore KW - Model-Driven Development KW - Architecture Description Language KW - Simulation Y1 - 2010 UR - https://www.unibw.de/technische-informatik/mitarbeiter/professoren/siegle/publikationen/ese2010_muco_modsim.pdf ER - TY - CHAP A1 - Bierl, Rudolf A1 - Boehm, M. A1 - Fraunhoffer, Judith A1 - Gardeia, Armin A1 - Mottok, Jürgen A1 - Schneider, Ralph A1 - Streubel, J. T1 - “Regensburger Modell zu den P-Seminaren” – Ein Konzept zur Gestaltung der Schnittstelle Gymnasium – Hochschule und zur Praxis einer kooperativen Lehr-Lern-Didaktik für Informationstechnik T2 - 3rd Embedded Software Engineering Congress, 7. bis 9. Dezember, Sindelfingen Y1 - 2010 PB - Vogel Business Media CY - Würzburg ER - TY - CHAP A1 - Hobelsberger, Martin A1 - Dumke, Reiner A1 - Mottok, Jürgen A1 - Niemetz, Michael A1 - Wirrer, Gerhard T1 - An Experience-Based Repository of Reusable Components for an Component-Based Automotive Software System T2 - Applied Software Measurement, proceedings of the joined International Conferences on Software Measurement IWSM/MetriKon/Mensura 2010, 10.-12. November 2010, Stuttgart, Germany Y1 - 2010 SP - 218 EP - 240 ER - TY - CHAP A1 - Hagel, Georg A1 - Mottok, Jürgen A1 - Utesch, Matthias A1 - Landes, Dieter A1 - Studt, Reimer T1 - Software Engineering Lernen für die berufliche Praxis – Erfahrungen mit dem konstruktivistischen Methodenbaukasten T2 - Proceedings of the 3rd Embedded Software Engineering Congress, 7. bis 9. Dezember 2010, Sindelfingen Y1 - 2010 ER - TY - CHAP A1 - Braun, Jürgen A1 - Mottok, Jürgen A1 - Miedl, Christian A1 - Greyer, D. A1 - Minas, Mark T1 - Fail-Safe und Fault-Tolerant Mechanismen T2 - Proceedings of the 3rd Embedded Software Engineering Congress, 7. bis 9. Dezember 2010, Sindelfingen Y1 - 2010 SP - 378 EP - 386 ER - TY - JOUR A1 - Deubzer, Michael A1 - Mottok, Jürgen T1 - Dependability von Systemen mit dynamischen Multicore-Schedulingalgorithmen JF - safetronic Y1 - 2010 ER - TY - JOUR A1 - Raab, Peter A1 - Mottok, Jürgen A1 - Meier, Hans T1 - OSEK-RTOS für Jedermann (Teil 1) JF - Embedded Software Engineering Report Y1 - 2009 VL - 53 IS - September SP - 14 EP - 15 ER - TY - CHAP A1 - Braun, Jürgen A1 - Mottok, Jürgen A1 - Miedl, Christian A1 - Geyer, Dirk A1 - Minas, Mark T1 - Overview and Evaluation of Fail-Safe and Fault-Tolerant Mechanisms for the Electromobility according to ISO26262 T2 - 1st International Electromobility Congress, 12. - 13. 5. 2011, Prague Y1 - 2011 ER - TY - CHAP A1 - Krämer, Stefan A1 - Mottok, Jürgen A1 - Meier, Hans T1 - Osek-basierende Implementierung des LLREF-Scheduling-Algorithmus für eine Dual-Core-Architektur T2 - 2. Landshuter Symposium Mikrosystemtechnik, Tagungsband, 24. une 25. Februar 2010, Hochschule Landshut Y1 - 2010 SP - 343 EP - 349 ER - TY - CHAP A1 - Steindl, Michael A1 - Mottok, Jürgen A1 - Meier, Hans A1 - Schiller, Frank A1 - Früchtl, M. T1 - Safeguarded Processing of Sensor Data T2 - 5th Embedded Real Time Software and Systems Conference (ERTS2 2010), May 2010, Toulouse, France Y1 - 2010 ER - TY - CHAP A1 - Raab, Peter A1 - Krämer, Stefan A1 - Mottok, Jürgen T1 - Cyclic codes and error detection during data processing in embedded software systems T2 - Proceedings of the 4rd Embedded Software Engineering Congress (ESE), 5.-9. Dezember 2011, Sindelfingen Y1 - 2011 SP - 577 EP - 590 ER - TY - CHAP A1 - Schmidhuber, Stefan A1 - Deubzer, Michael A1 - Mottok, Jürgen T1 - Parallelisierte Echtzeitanalyse von Eingebetteten Systemen T2 - Proceedings of the 4rd Embedded Software Engineering Congress (ESE), 5.-9. Dezember 2011, Sindelfingen Y1 - 2011 SP - 516 EP - 524 ER - TY - JOUR A1 - Bärwald, Andreas A1 - Hauff, Harald A1 - Mottok, Jürgen T1 - Qualifizierung und Zertifizierung von Software-Entwicklungswerkzeugen JF - Hanser Automotive Y1 - 2010 SP - 34 EP - 39 ER - TY - JOUR A1 - Krämer, Stefan A1 - Mottok, Jürgen A1 - Meier, Hans T1 - Multi-Core Scheduling in Embedded Systemen, Teil 1 JF - Hanser Automotive Y1 - 2010 IS - 1-2 SP - 18 EP - 22 ER - TY - JOUR A1 - Krämer, Stefan A1 - Mottok, Jürgen A1 - Meier, Hans T1 - Multi-Core Scheduling in Embedded Systemen, Teil 2 JF - Hanser Automotive Y1 - 2010 IS - 3-4 SP - 23 EP - 25 ER - TY - JOUR A1 - Krämer, Stefan A1 - Mottok, Jürgen A1 - Meier, Hans T1 - Multi-Core Scheduling in Embedded Systemen, Teil 3 JF - Hanser Automotive Y1 - 2010 IS - 5-6 SP - 14 EP - 16 ER - TY - CHAP A1 - Mottok, Jürgen A1 - Gardeia, Armin T1 - The regensburg concept of p-seminars – how to organize the interface between secondary school and university education to create a didactic cooperation between teaching and learning of software engineering with lego mindstorms nxt embedded robot systems T2 - 2011 IEEE Global Engineering Education Conference (EDUCON), Amman, Jordan, 2011 N2 - This paper describes the background and the theory of the learning arrangement “The Regensburg Concept of P 1 - Seminars” and its potential fields of application. This conception was designed to meet the various requirements caused by the Bologna Accords and the restructuring of the senior years of German secondary school education. At the same time it aims at finding solutions for a severe problem topical in Germany: the lack of students qualifying in MINT (the fields of mathematics, informatics, natural sciences and techniques.) The focus of this conception is on the cooperation between universities and schools hence a draft of the P-Seminar has already been realized and evaluated during a pilot phase at a local secondary school. These experiences serve as a solid basis for the development of a concrete plan that makes it possible to transfer the concept to similar projects in future. In the following paragraphs keywords that are applied to the lexical field of the Regensburg Concept are elaborated e.g. "practive learning", an interaction of practical and active learning. Y1 - 2011 U6 - https://doi.org/10.1109/EDUCON.2011.5773255 SP - 917 EP - 920 ER - TY - CHAP A1 - Altmann, Andreas A1 - Birkner, Wolfgang A1 - Häckl, Franz-Xaver A1 - Hanner, Christopher A1 - Liebhart, Peter A1 - Metschl, Samuel A1 - Weck, Florian A1 - Farmbauer, Michael A1 - Heiß, Manfred A1 - Cuno, H.-H. A1 - Fuhrmann, Thomas A1 - Mandl, Roland A1 - Mottok, Jürgen A1 - Niemetz, Michael T1 - Payload development and launch of a stratosphere balloon mission T2 - IEEE Global Engineering Education Conference (EDUCON 2014), 3-5 April 2014, Istanbul, Turkey N2 - During a student project a stratosphere balloon was developed and launched. This project included the definition of the balloon parameters and the scientific instruments for performing atmospheric measurements, the development of all mechanical and electronic parts, the administration of the project as well as the management tasks related to the balloon launch. The main challenge for the students was the high complexity of the project due to tasks involving many different knowledge domains and the long project duration from the initial definition to the launch. Y1 - 2014 U6 - https://doi.org/10.1109/EDUCON.2014.6826065 ER - TY - JOUR A1 - Raab, Peter A1 - Krämer, Stefan A1 - Mottok, Jürgen A1 - Vavricka, Vlastimil T1 - Isomorphism between Linear Codes and Arithmetic Codes for Safe Data Processing in Embedded Software Systems JF - Computing and Informatics (CAI) N2 - We present a transformation rule to convert linear codes into arithmetic codes. Linear codes are usually used for error detection and correction in broadcast and storage systems. In contrast, arithmetic codes are very suitable for protection of software processing in computer systems. This paper shows how to transform linear codes protecting the data stored in a computer system into arithmetic codes safeguarding the operations built on this data. Combination of the advantages of both coding mechanisms will increase the error detection capability in safety critical applications for embedded systems by detection and correction of arbitrary hardware faults. Y1 - 2014 UR - https://pdfs.semanticscholar.org/eb7c/f626eb4dcf33bb9c615d477099188eadc76b.pdf?_ga=2.23977850.1374482597.1614464499-73487869.1612391519 VL - 33 SP - 721 EP - 734 ER - TY - CHAP A1 - Mottok, Jürgen A1 - Scharfenberg, Georg T1 - Forschendes Lernen im Masterstudiengang Applied Research in Engineering Sciences T2 - 4th Applied Research Conference, 5th July 2014, Ingolstadt Y1 - 2014 SN - 978-3-8440-2875-1 SP - 55 EP - 61 PB - Shaker CY - Aachen ER - TY - CHAP A1 - Scharfenberg, Georg A1 - Mottok, Jürgen T1 - Forschungsmaster entwickelt sich zum Wirtschaftsfaktor in Bayern T2 - 4th Applied Research Conference, 5th July 2014, Ingolstadt Y1 - 2014 SN - 978-3-8440-2875-1 SP - 55 EP - 61 PB - Shaker CY - Aachen ER - TY - CHAP A1 - Raab, Peter A1 - Mottok, Jürgen T1 - Modellbasierte Zuverlässigkeitsanalysen von arithmetischen Operationen in einem Prozessorsystem T2 - Proceedings of safe.tech 2014, 20. und 21. Mai 2014, München Y1 - 2014 ER - TY - CHAP A1 - Mottok, Jürgen T1 - Storytelling: Finite state machines Lernen leicht gemacht! T2 - Proceedings of the 4rd Embedded Software Engineering Congress (ESE), 5.-9. Dezember 2011, Sindelfingen Y1 - 2011 ER - TY - CHAP A1 - Mottok, Jürgen T1 - General purpose computing on graphics processing unit by using cuda T2 - Applied Research Conference 2011 (ARC 2011), 6. April, Regensburg Y1 - 2011 ER - TY - CHAP A1 - Mottok, Jürgen T1 - Ses and the iso 26262 T2 - Applied Research Conference 2011 (ARC 2011), 6. April, Regensburg Y1 - 2011 ER - TY - CHAP A1 - Mottok, Jürgen A1 - Alfranseder, Martin A1 - Schmidhuber, Stefan A1 - Mucha, Matthias A1 - Sailer, Andreas ED - Teodorescu, Horia-Nicolai ED - Kirschenbaum, Alan ED - Cojocaru, Svetlana ED - Bruderlein, Claude T1 - How to improve the reactiveness and efficiency of embedded multicore systems by use of probabilistic simulation and optimization techniques T2 - Improving Disaster Resilience and Mitigation - New Means and Tools. NATO Science for Peace and Security Series C: Environmental Security N2 - Safe and reliable multi-core technology becomes more and more important in the field of embedded systems. Today’s and future embedded systems require increasing performance while being more energy efficient. Moreover, the functional safety for these embedded systems has to be improved or developed completely new. In this chapter, we first address the challenges of embedded multi-core real-time systems. To raise the resilience of such systems we use the deadlock-free synchronization model of Block et al. (A flexible real-time locking protocol for multiprocessors. 2012 IEEE international conference on embedded and real-time computing systems and applications, vol 0, pp 47–56, 2007). The metric mean Normalized Blocking Time (mNBT) is hereby used to measure the timing effects of the blocking behavior of strongly interacting tasks. In a second step, we present a model-based approach to map the tasks of an embedded real-time system to the cores of a multi-core processor. Moreover, we derive an execution time model from runtime measurements of software functions. This information is then used to perform precise probabilistic simulations of different task-to-core mappings and evaluate them with regard to task response times, inter-task blocking overhead and load distribution. Subsequently, we integrate the probabilistic simulation within an optimization technique to systematically improve the task-to-core mapping. We conclude with a case-study, where we demonstrate the effectiveness of the presented approach by optimizing the task-to-core mapping of a practical automotive powertrain system. KW - Embed System KW - Functional Safety KW - Arrival Curve KW - Task Allocation Problem KW - Deadline Violation Y1 - 2014 U6 - https://doi.org/10.1007/978-94-017-9136-6_16 SP - 253 EP - 268 PB - Springer CY - Dodrecht ER - TY - CHAP A1 - Figas, Paula A1 - Knörl, Susanne A1 - Mörtlbauer, Stefanie A1 - Sedelmaier, Yvonne A1 - Schroll-Decker, Irmgard ED - Hagel, Georg ED - Mottok, Jürgen T1 - Developing Software Engineering Education as a Didactical Discipline in its own right T2 - 1st European Conference on Software Engineering Education (ECSEE) at Seon Monastery, Germany N2 - Simultaneously to the growing significance of the discipline software engineering (SE) also its education becomes more important. This reinforces the need of a theoretical foundation of software engineering education, but there is still a lack of scientifically justified didactical concepts. In the context of the project EVELIN (Experimental Improvement in Learning Software Engineer-ing) the authors want to give a decisive impulse for the development of a “Fachdidaktik software engineering” (FD-SE). In order to compile an adequate theoretical basis for a Fachdidaktik of software engineering “Allgemeine Did-aktik” (AD)1, its relation to “Fachdidaktik” (FD) in general, the special branch of science of software engineering and related scientific disciplines are dis-cussed. This analysis is used to justify the necessity of an autonomous scientific discipline Fachdidaktik software engineering which meets the challenges of teaching and learning software engineering. The main contributions of this pa-per are proposals on how this FD can be built scientifically upon AD, on the one hand, and how it can be implemented by specific didactical approaches for software engineering, on the other hand. KW - Fachdidaktik KW - Software Engineering KW - Lehre KW - Hochschule Y1 - 2014 UR - https://www.researchgate.net/publication/269762126_Developing_Software_Engineering_Education_as_a_Didactical_Discipline_in_its_own_right SP - 1 EP - 15 PB - Shaker Verlag ER - TY - CHAP A1 - Schmidhuber, Stefan A1 - Deubzer, Michael A1 - Mader, Ralph A1 - Niemetz, Michael A1 - Mottok, Jürgen T1 - Towards the Derivation of Guidelines for the Deployment of Real-Time Tasks on a Multicore Processor T2 - 4th International Symposium on Model-Based Safety and Assessment (IMBSA 2014), Munich, Germany, October 27-29, 2014, Proceedings N2 - The deployment of automotive software on a multicore processor includes the task of mapping executables to cores. Given the number of possible solutions, integrators have to solve a complex problem. Considering multiple, often conflicting goals like minimizing task response times and memory consumption, complexity further increased with the advent of multicore processors. We present a model-based approach for deriving design rules supporting integrators with statically mapping tasks to a multicore ECU. First, an evolutionary algorithm is used to sample the design space. For each sample, a model-based analysis is performed, resulting in the required fitness values according to the system metric objectives. Finally, subsets of the sample population are used to derive deployment guidelines by evaluating similarities between highly ranked solutions. This reduces the number of solutions to be considered by the integrators by orders of magnitude. In a case-study, we demonstrate the developed approach on an artificial automotive engine management system. KW - Real-time systems KW - embedded multicore systems KW - runnable partitioning KW - task-to-core mapping KW - software integration KW - design space exploration KW - evolutionary algorithm Y1 - 2014 SN - 978-3-319-12213-7 U6 - https://doi.org/10.1007/978-3-319-12214-4_12 SP - 152 EP - 165 PB - Springer CY - Munich ER - TY - CHAP A1 - Oklapi, Erna A1 - Deubzer, Michael A1 - Schmidhuber, Stefan A1 - Lalo, Erjola A1 - Mottok, Jürgen T1 - Optimization of Real-Time Multicore Systems Reached by a Genetic Algorithm Approach for Runnable Sequencing T2 - 2014 International Conference on Applied Electronics, Pilsen, Czech Republic N2 - The deployment of complex real-time systems with everyday increasing demands and possibilities, is a challenging task for engineers when performance and efficiency have to be maximized while cost have to be minimized at the same time. For already designed systems it became necessary to perform different modifications in order to find optimal software architecture configuration by respecting all timing constraints which are essential when speaking of real-time systems. In this work, we present a model-based approach of optimizing the execution sequence of runnables within tasks in order to reduce the system's reaction times by improving the overall signal flow duration. Hereby, a genetic optimization algorithm is used to create and evaluate multiple solutions for the runnable sequencing problem. We conclude by demonstration the efficiency of the presented approach with experimental results. KW - runnable sequencing KW - embedded real-time systems KW - genetic algorithms KW - multi-core KW - optimization Y1 - 2014 U6 - https://doi.org/10.1109/AE.2014.7011709 SP - 233 EP - 238 ER - TY - CHAP A1 - Soska, Alexander A1 - Mottok, Jürgen T1 - A New Conceptual Contribution for Serious Games in Academic Software Engineering Education T2 - European Conference on Software Engineering Education 2014 (ECSEE), 27 and 28 November 2014 in Seeon Monastery N2 - Nowadays, the popularity and field of application of serious games grows steadily. This educational method offers attractive pportunities for teaching and training by combining playful elements with learning content. By using game mechanics, thinking and technique, theoretical subject matters are treated in a fun and engaging way. Thereby, serious games utilize our intrinsic motivation to discover the surroundings in a playful manner. Embedded in educational settings, the goal is to mediate academic and non-academic knowledge to the students. Especially in the field of software engineering it is important to have skills which go beyond pure technical knowledge. Yet, the use of serious games is still a manageable amount. With this paper, we give a contribution to the theoretical design and development of serious games based on playful learning method and its relation to research-based learning in universal context. In addi- tion we analyze the existing serious games in software engineering and present our thoughts about planning our own. Y1 - 2014 UR - https://www.researchgate.net/publication/277266392_A_New_Conceptual_Contribution_for_Serious_Games_in_Academic_Software_Engineering_Education SN - 978-3-8440-3067-9 SP - 241 EP - 254 PB - Shaker CY - Aachen ER - TY - CHAP A1 - Soska, Alexander A1 - Schumm, Michael A1 - Joseph, Saskia A1 - Reschke, Michael A1 - Mottok, Jürgen A1 - Niemetz, Michael A1 - Schroll-Decker, Irmgard T1 - Comparison of Frontal Lecture and Workshop Learning Arrangements in a Software Engineering Education Project T2 - 2014 IEEE Global Engineering Education Conference (EDUCON), Istanbul, Turkey N2 - The increase in complexity of software and its creation over the last decades requires an increase in the quality of the education of software engineering professionals. The number of Universities which answer this call by replacing or extending lectures with simulated software projects is constantly rising. However, the question how to best transfer new technological knowledge needed to be successful within this projects to the students remains open. Therefore this paper will present a comparison between the classical frontal lecture and a modern workshop learning arrangement used within these projects. By the use of workshops not only the knowledge transfer but also the acquisition of personal and social competences will be facilitated. Furthermore positive experiences with workshops at university level will support life-long learning. Y1 - 2014 U6 - https://doi.org/10.1109/EDUCON.2014.6826162 SP - 653 EP - 658 ER - TY - CHAP A1 - Krämer, Stefan A1 - Raab, Peter A1 - Mottok, Jürgen A1 - Racek, Stanislav T1 - Comparison of Enhanced Markov Models and Discrete Event Simulation – for evaluation of probabilistic Faults in safety-critical real-time task sets T2 - Proceedings of EUROMICRO DSD 2014 - 17th Euromicro Conference on Digital System Design N2 - In this paper we present simulation and model based approaches for evaluating and validating the temporal and safety relevant properties of software intensive safety-critical real-time embedded systems. A high level reliability model of a safe task execution is described by a continuous-time Markov process, enhanced by the modeling of execution times. It is shown that the behavior - regarding real-time and safety metrics - of this theoretical model can be transferred into an abstract system timing model, which then can be analyzed by a discrete event simulation approach. The verification of the discrete event simulation by Markov models offers the possibility of a holistic approach for reliability analysis combined with schedulability analysis of complex safety-critical multicore real-time systems by the discrete event simulation. KW - Model KW - Stochastic simulation KW - reliability analysis KW - safe software processing KW - real-time operating system KW - multicore scheduling KW - discrete event simulation KW - fault injection Y1 - 2014 U6 - https://doi.org/10.1109/DSD.2014.42 SP - 591 EP - 598 ER - TY - CHAP A1 - Krämer, Stefan A1 - Simsek, Erol A1 - Braun, Jürgen A1 - Deubzer, Michael A1 - Stingl, Armin A1 - Hobelsberger, Martin A1 - Mottok, Jürgen T1 - Mut zu Fehlern, um die Qualität zu steigern – Fault-Injection zur Steigerung der Zuverlässigkeit T2 - Tagungsband, 6th Embedded Software Engineering, Kongress 2013, 2. bis 6. Dezember 2013, Sindelfingen Y1 - 2013 SN - 978-3-8343-2408-5 SP - 577 EP - 585 ER - TY - CHAP A1 - Oklapi, Erna A1 - Deubzer, Michael A1 - Schmidhuber, Stefan A1 - Mottok, Jürgen T1 - Verification of an Evolutionary Optimization Algorithm for Runnable Sequencing Problem T2 - 4th Applied Research Conference, 5th July 2014, Ingolstadt Y1 - 2014 ER - TY - CHAP A1 - Schmittner, Christoph A1 - Scharfenberg, Georg A1 - Mottok, Jürgen A1 - Strassmeier, Stefan A1 - Limmer, Thomas T1 - Analysis of the functional and electrical safety of charging stations T2 - 2nd Applied Research Conference 2012 (ARC 2012), 25./26. June 2012, Nuremberg N2 - The number of public charging stations for electric vehicles is rising. It's estimated that in 2014 more than 1.000.000 public charging stations will be installed worldwide. Currently there is no specific standard for Functional Safety and the standard for Electrical Safety is derived from standards for similar systems. The intent of this paper is to examine the existing safety architecture of mode 3 charging stations. First the standards for the charging process and the different modes are presented. Then a standard architecture for a mode 3 charging station, based on the IEC 61841, is described. After that a risk analysis of this model is performed and the electrical and Functional Safety of the architecture are analyzed. Both analyses are based on the general safety standards VDE 0100 and IEC 61508. After that possibilities for improvements and future challenges with Mode 4 charging are discussed. Y1 - 2012 SP - 80 EP - 85 ER - TY - JOUR A1 - Braun, Jürgen A1 - Geyer, Dirk A1 - Mottok, Jürgen T1 - Alternative measure for safety related software JF - ATZelektronik N2 - Wie kann die funktionale Sicherheit in Fahrzeugen zukunftssicher und effektiv gewährleistet werden? Und wie kann dies speziell in elektrifizierten Antrieben gelingen? Mit dieser Aufgabenstellung haben sich AVL in Kooperation mit dem LaS³ und der Universität der Bundeswehr München in einem Forschungsprojekt beschäftigt. Die Antwort lautet: Die automatischen Speichertests in Zusammenspiel mit der Programmfluss-Überwachung und redundanter Hardware können besonders effektiv durch die „Codierte Verarbeitung“ ersetzt werden. Denn hier wird die Diversität in Software erhöht, um die aufwendigere und kostspielige Redundanz von Hardware zu reduzieren. Y1 - 2012 SN - 1862-1791 IS - 04 SP - 40 EP - 43 ER - TY - CHAP A1 - Schmidhuber, Stefan A1 - Deubzer, Michael A1 - Mottok, Jürgen ED - Mottok, Jürgen ED - Ziemann, Olaf T1 - Genetic optimization of real-time multicore systems with respect to communication-based metrics T2 - 2nd Applied Research Conference 2012 (ARC 2012) 25./26. June 2012, Nuremberg Y1 - 2012 SN - 978-3-8440-1093-0 SP - 21 EP - 25 PB - Shaker CY - Aachen ER - TY - CHAP A1 - Sailer, Andreas A1 - Schmidhuber, Stefan A1 - Deubzer, Michael A1 - Hobelsberger, Martin A1 - Mottok, Jürgen T1 - Requirements engineering for a continuous design flow and methodology T2 - 2nd Applied Research Conference 2012 (ARC 2012) 25./26. June 2012, Nuremberg Y1 - 2012 SN - 978-3-8440-1093-0 SP - 76 EP - 79 PB - Shaker CY - Aachen ER - TY - CHAP A1 - Schmidhuber, Stefan A1 - Sailer, Andreas A1 - Deubzer, Michael A1 - Hobelsberger, Martin A1 - Mottok, Jürgen T1 - Overview of the itea2-project amalthea T2 - 2nd Applied Research Conference 2012 (ARC 2012) 25./26. June 2012, Nuremberg Y1 - 2012 SN - 978-3-8440-1093-0 SP - 60 EP - 62 PB - Shaker CY - Aachen ER - TY - JOUR A1 - Ostermeier, Daniel A1 - Mottok, Jürgen A1 - Knorr, Christine A1 - Huber, Michael ED - Mottok, Jürgen ED - Ziemann, Olaf T1 - Competence Atlas for Save and Green Road Vehicles in the Electro Mobility Cluster Regensburg JF - Applied Research Conference 2012 (ARC 2012) 25./26. June 2012, Nuremberg Y1 - 2012 SP - 86 EP - 92 ER - TY - CHAP A1 - Alfranseder, Martin A1 - Mottok, Jürgen T1 - Benchmarking parallelisierbarer Algorithmen auf cuda Architekturen T2 - Tagungsband 5th Embedded Software Engineering Kongress, 3. bis 7. Dezember 2012, Sindelfingen Y1 - 2012 PB - Vogel Business Media CY - Würzburg ER - TY - CHAP A1 - Mottok, Jürgen T1 - Migration path for secure and economic smart power grid devices with transitional smart metering support T2 - 2nd Applied Research Conference 2012 (ARC 2012), 25./26. June 2012, Nuremberg Y1 - 2012 SP - 64 EP - 70 ER - TY - JOUR A1 - Mottok, Jürgen T1 - Embedded functional safety, funktional safety in der praxis JF - Bayern Innovativ Y1 - 2012 ER - TY - CHAP A1 - Bock, T. A1 - Mottok, Jürgen A1 - Köhler, T. ED - Mottok, Jürgen ED - Ziemann, Olaf T1 - A gesture-based human-machine interface using stereoscopic depth images T2 - 2nd Applied Research Conference 2012 (ARC 2012), 25./26. June 2012, Nuremberg N2 - Reasonable integration of gesture-based automotive HMI-functionality offers potential safety benefits by reducing driver distractions and glance times to operate tertiary in-car devices. Stereo camera systems are a well investigated choice to perform the task of generating depth data for spatial gesture recognition. This paper describes the functionality of our stereo vision software, which is intended for application in a target system based on CMOS wafer-level cameras. The retrieved point cloud data was passed to a gesture-based sample application. Y1 - 2012 SP - 166 EP - 169 PB - Shaker CY - Aachen ER - TY - CHAP A1 - Landes, Dieter A1 - Sedelmaier, Yvonne A1 - Pfeiffer, Volkhard A1 - Mottok, Jürgen A1 - Hagel, Georg T1 - Learning and teaching software process models T2 - Proceedings of the 2012 IEEE Global Engineering Education Conference (EDUCON), 17-20 April 2012, Marrakech, Morocco N2 - Software process models are fairly abstract tools for organizing large, complex software development projects. Since particularly undergraduate students commonly do not have any experience in being part of such a project, their understanding of the benefits and shortcomings of particular process models is very limited. Even more, frequently they are not aware of the need to follow a particular process model since their previous one-person software assignments were too small for requiring any such model at all. Y1 - 2012 U6 - https://doi.org/10.1109/EDUCON.2012.6201191 ER - TY - CHAP A1 - Abke, Jörg A1 - Brune, Philipp A1 - Haupt, Wolfram A1 - Hagel, Georg A1 - Landes, Dieter A1 - Mottok, Jürgen A1 - Niemetz, Michael A1 - Pfeiffer, Volkhard A1 - Studt, Reimer A1 - Schroll-Decker, Irmgard A1 - Sedelmaier, Yvonne T1 - Evelin – ein Forschungsprojekt zur systematischen Verbesserung des Lernens von Software Engineering T2 - Tagungsband 5th Embedded Software Engineering Kongress, 3. bis 7. Dezember 2012, Sindelfingen Y1 - 2012 SN - 978-3-8343-2407-8 SP - 653 EP - 658 ER - TY - CHAP A1 - Joseph, Saskia A1 - Schumm, Michael A1 - Schroll-Decker, Irmgard A1 - Niemetz, Michael A1 - Mottok, Jürgen T1 - Anmerkungen zur Kompetenz-Performanz-Relation: Software Engineering im Spannungsfeld der beruflichen Anforderungen T2 - Tagungsband 5th Embedded Software Engineering Kongress, 3. bis 7. Dezember 2012, Sindelfingen Y1 - 2012 ER - TY - BOOK A1 - Gebhard, Vera A1 - Rieger, Gerhard M. A1 - Mottok, Jürgen A1 - Gießelbach, Christian T1 - Funktionale Sicherheit nach ISO 26262 BT - Ein Praxisleitfaden zur Umsetzung KW - Funktionssicherheit KW - ISO/DIS 26262 KW - Kraftfahrzeugbau KW - OEM KW - Produktentwicklung Y1 - 2013 SN - 978-3-89864-788-5 PB - dpunkt.verlag CY - Heidelberg ER - TY - CHAP A1 - Nick, Matthias A1 - Schorer, Michael A1 - Mottok, Jürgen ED - Mottok, Jürgen ED - Ziemann, Olaf T1 - Feasibility Study of a Build System Performing Automated Builds Based on Model-Based Build Descriptions T2 - 2nd Applied Research Conference 2012 (ARC 2012), 25./26. June 2012, Nuremberg Y1 - 2012 SP - 71 EP - 75 PB - Shaker CY - Aachen ER - TY - CHAP A1 - Steindl, Michael A1 - Mottok, Jürgen T1 - Deriving an integration order in a component-based embedded system using simulated annealing T2 - Proceedings of the 13. Mitteldeutschen Nachwuchswissenschaftlerkonferenz (NWK13), April 2012, Goerlitz, Germany Y1 - 2012 SN - 978-3-86870-436-5 ER - TY - CHAP A1 - Steindl, Michael A1 - Mottok, Jürgen T1 - Optimizing Software Integration Testing by Considering Integration Testability and Test Complexity T2 - 10th IEEE Workshop on Intelligent Solutions in Embedded Systems, 2012, Klagenfurt, Austria Y1 - 2012 ER - TY - CHAP A1 - Mottok, Jürgen T1 - Dependable multicore scheduling T2 - Continental Software Conference Y1 - 2012 ER - TY - CHAP A1 - Beslmeisl, Magdalena A1 - Schroll-Decker, Irmgard A1 - Mottok, Jürgen T1 - Application of a Reflective Learning Approach in Software Engineering. Circularity as a relevant characteristic of a reflective teaching and learning approach T2 - European Conference of Software Engineering Education (ECSEE2016), 30 June and 1 July 2016 in Seeon Monastery, Germany N2 - The pedagogic motivation of this contribution is to develop, to adapt and to examine a specific tertiary teaching-learning situation and its changes due to a constant reflection. Within the scope of the BMBF fostered project " EVELIN " the learning teaching-Arrangement (TLA) " The Online Learning Journal (OLJ) – a tool complementing the software engineering lecture " is realized a second time at the OTH Regensburg. This further development is examined from a pedagogic perspective. This paper deals with issues concerning the conscious modification of specific teaching actions, therefore the changes of the teachers' attitude as well as the reaction of the students regarding this teaching actions. Two important findings are: (1) The teaching staff is able to adapt their teaching–actions on given conditions because of the awareness of their own teaching-attitude. (2) Due to a reflective teaching practice, there is a great potential for goal oriented learning in the context of higher education. Y1 - 2016 SP - 19 EP - 33 PB - Shaker CY - Aachen ER - TY - CHAP A1 - Nivala, Markus A1 - Hauser, Florian A1 - Mottok, Jürgen A1 - Gruber, Hans T1 - Developing visual expertise in software engineering: An eye tracking study T2 - IEEE Global Engineering Education Conference (EDUCON), 10-13 April 2016, Abu Dhabi, UAE N2 - Program comprehension and the ability to find program errors are key skills of software engineering. The aim of this pilot study was to examine the visual processes of novice and advanced programmers in authentic tasks. Fifteen novices and eight advanced programmers were given eight short pieces of code. Their task was to either identify an error or give the output of the code. Eye movements and keyboard activity were recorded. On average, the novices spent more time reading the code than composing the response, whereas the more advanced programmers started composing the response sooner and spent more time on it. In general, the advanced programmers had shorter fixations and saccades. The results suggest that the advanced programmers are quicker to grasp the essence of the code and able to see more details in it. The advanced programmers had shorter fixations and saccade lengths during the second phase which might indicate the process of chunking. KW - program comprehension KW - debugging KW - software engineering KW - visual expertise KW - eye tracking Y1 - 2016 U6 - https://doi.org/10.1109/EDUCON.2016.7474614 SP - 613 EP - 620 ER - TY - CHAP A1 - Knorl, Susanne A1 - Soska, Alexander A1 - Schroll-Decker, Irmgard A1 - Mottok, Jürgen T1 - Reconstructing students’ subjective theories on self-directed learning a qualitative research approach in Software Engineering education T2 - 2015 IEEE Global Engineering Education Conference (EDUCON), 18-20 March 2015, Tallinn, Estonia N2 - Considering the claim of furthering self-directed learning in higher education in general and in Software Engineering education in particular, this paper deals with a new approach on understanding and facilitating self-directed learning. This approach involves the concept of subjective theories, which are expected to influence students' self-directed learning. Therefore this paper presents the intended qualitative research design for reconstructing these subjective theories and for developing ways of integrating them in didactical situations in higher education and especially in Software Engineering education. Y1 - 2015 U6 - https://doi.org/10.1109/EDUCON.2015.7095990 SP - 314 EP - 317 ER - TY - CHAP A1 - Soska, Alexander A1 - Mottok, Jürgen A1 - Wolff, Christian T1 - Playful learning in academic software engineering education T2 - 2015 IEEE Global Engineering Education Conference (EDUCON), 18-20 March 2015, Tallinn, Estonia N2 - Within this thesis, we present our suggestions why playful learning in software engineering education is useful to mediate generic competences in academic teaching. Therefor we identified competences which are addressed by playful learning and mapped them to demanded generic competences in software engineering. Due to the well compliance, we analyzed current implementations of playful learning and their design regarding the mediation of required soft skills. Based on the lack of effective implementation, we close our paper with an exemplary design for playful learning. Y1 - 2015 U6 - https://doi.org/10.1109/EDUCON.2015.7095992 SP - 324 EP - 332 ER - TY - CHAP A1 - Beslmeisl, Magdalena A1 - Krekeler, T. A1 - Schroll-Decker, Irmgard A1 - Mottok, Jürgen T1 - Der begleitende Einsatz des Online Lerntagebuchs (OLTB) im Software Engineering; als Instrument zur individuellen Lernstandortbestimmung T2 - 2. HD MINT Symposium, 2015, Nürnberg Y1 - 2015 SP - 148 EP - 154 ER - TY - CHAP A1 - Ye Tao, A1 - Guozhu Liu, A1 - Mottok, Jürgen A1 - Hackenberg, Rudolf A1 - Hagel, Georg T1 - Just-in-Time-Teaching experience in a Software Design Pattern course T2 - 2015 IEEE Global Engineering Education Conference (EDUCON), 18-20 March 2015, Tallinn, Estonia Y1 - 2015 SP - 915 EP - 919 ER - TY - CHAP A1 - Martin, Felix A1 - Sailer, Andreas A1 - Deubzer, Michael A1 - Mottok, Jürgen T1 - Automatische Multicore-Echtzeitvalidierung – Ein Prozess für modellbasierte Softwareentwicklung T2 - Tagungsband 8th Embedded Software Engineering Kongress (ESE), 30.11. - 04.12.2015, Sindelfingen Y1 - 2015 ER - TY - CHAP A1 - Beslmeisl, Magdalena A1 - Schroll-Decker, Irmgard A1 - Mottok, Jürgen T1 - Turning to adaption through exploration in the education of Software Engineering T2 - Proceedings of the Exploring Teaching for Active Learning in Engineering Education (ETALEE), 11 - 12 November 2015, Copenhagen Y1 - 2015 ER - TY - CHAP A1 - Martin, Felix A1 - Sailer, Andreas A1 - Deubzer, Michael A1 - Mottok, Jürgen T1 - Automation of a Closed Loop Model-Based Development Process T2 - Applied Research Conference 2015 (ARC 2015), 3rd July 2015, Nürnberg Y1 - 2015 ER - TY - CHAP A1 - Soska, Alexander A1 - Reuter, Rebecca A1 - Hauser, Florian A1 - Reiß, Markus A1 - Mottok, Jürgen T1 - Scaffolding in der Lehre von Design Pattern. Neue Konzepte für anwendungsorientiertes und aktivierendes Lernen T2 - Tagungsband zum 3. Symposium zur Hochschullehre in den MINT-Fächern, 25. / 26. September 2017, TH Nürnberg N2 - Design Pattern sind wiederverwendbare Entwurfsmuster für Probleme in objektorientierten Programmiersprachen. Gene-rell wird dieser Lerninhalt als sehr abstrakt, theoretisch und schwer verständlich beurteilt. Eine durchgeführte Studie mit Studierenden zu den Lernhindernissen während unseres Soft-ware Engineering Curriculums belegen diese Annahmen. Trotz heterogener Studierendengruppe mit unterschiedlichen Vor-kenntnissen, wird das Verständnis der Konzepte von Design Pattern, verglichen mit anderen Lehrinhalten, als die größte Herausforderung angesehen. Zur Verbesserung des Lernens von Design Pattern, wurde aufgrund dieser Erkenntnisse ein Lehrkonzept zur Beseitigung der Lernhindernisse entwickelt. Dieses basiert auf einem angepassten Scaffolding-Ansatz, welcher u.a. durch die systematische Anwendung von studie-rendenzentrierten Methoden die Aneignung von theoretischen als auch praktischen Inhalten sukzessive fördert. Eine anschlie-ßende Evaluation belegt die Wirkungsweise des Lehrkonzepts. Y1 - 2017 UR - https://www.th-nuernberg.de/fileadmin/abteilungen/sll/Dokumente/Hochschuldidaktik/MINT_Symposium/Tagungsband_MINT_Symposium_2017.pdf SP - 112 EP - 116 ER - TY - CHAP A1 - Langer, Tobias A1 - Osinski, Lukas A1 - Mottok, Jürgen T1 - A Survey of Parallel Hard-Real Time Scheduling on Task Models and Scheduling Approaches T2 - ARCS 2017; 30th International Conference on Architecture of Computing Systems, 3-6 April 2017, Vienna, Austria N2 - The trend towards multi-core systems becomes increasinglyomnipresentandhasalreadyreachedhardreal-time systems. In the recent years more and more researchers tackle the problem of scheduling parallel tasks with real-time constraints. We present a discussion of these recent approaches to hard real-time scheduling tasks consisting of multiple threads. We identify categories in scheduling mechanisms and task systems and discuss their features, as well as the research already achieved in their ???elds. In the domain of task models we identi???ed the gang constrained task model, the order constrained task model and the unconstrained task model. These task models differ regardingtheamountandtypeofthreadexecutionconstraints, which can be expressed using the model. Regarding scheduling algorithms, we identi???ed transformation based and nontransformation based scheduling schemes. The former rely on off-line task transformation, whereas the latter doesn???t require any prior information about task structures. The presented classi???cations show, that applied scheduling algorithms mostly are not restricted to certain task models, but that they are applied quite independently. Y1 - 2017 UR - https://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=7948560 ER - TY - CHAP A1 - Sailer, Andreas A1 - Deubzer, Michael A1 - Lüttgen, Gerald A1 - Mottok, Jürgen T1 - Comparing Trace Recordings of Automotive Realtime Software T2 - RTNS '17: Proceedings of the 25th International Conference on Real-Time Networks and Systems, Grenoble, France, IEEE N2 - The process of engineering models of existing real-time system components is often difficult and time consuming, especially when legacy code has to be re-used or information about the exact timing behaviour is needed. In order to tackle this reverse engineering problem, we have developed the tool CoreTAna. CoreTAna derives an AUTOSAR compliant model of a real-time system by conducting dynamic analysis using trace recordings. Motivated by the challenge of assessing the quality of reverse engineered models of real-time software, we present a novel mathematical measure for comparing trace recordings from embedded real-time systems regarding their temporal behaviour. We also introduce a benchmark framework based on this measure, for evaluating reverse engineering tools such as CoreTAna. This considers common system architectures and also includes randomly generated systems and three systems of industrial automotive projects. Finally, an industrial case study demonstrates other use cases of our measure, such as impact analysis. Y1 - 2017 U6 - https://doi.org/10.1145/3139258.3139265 SP - 118 EP - 127 ER - TY - CHAP A1 - Soska, Alexander A1 - Mottok, Jürgen A1 - Wolff, Christian T1 - Pattern oriented card game development: SOFTTY - A card game for academic learning of software testing T2 - IEEE Global Engineering Education Conference (EDUCON), 25-28 April 2017, Athens, Greece N2 - One of the biggest problems of educational games is the adequate integration of learning content into the game environment. Thereby the main challenge is to create a balance between gameplay and learning objectives and the correct transfer of learning principles into the game design. A useful approach is to identify game components and their specific learning constraints and the relationship between each other. By mapping learning elements to Game Design Pattern, we elaborate fundamentals for the concrete game design, focusing on card games. A shared description and an understanding of how the game design aligns with learning content facilitates the development of high quality educational games. A short illustration of our further developed implementation summarizes our experiences and shows an exemplary realization. Y1 - 2017 U6 - https://doi.org/10.1109/EDUCON.2017.7942996 ER - TY - CHAP A1 - Reuter, Rebecca A1 - Beslmeisl, Magdalena A1 - Mottok, Jürgen T1 - Work in Progress: Teaching-Obstacles in Higher Software Engineering Education T2 - 8th IEEE Global Engineering Education Conference (EDUCON 2017), Athens, Greece N2 - Software Engineering is very abstract and complex by nature. Teaching Software Engineering in higher education is therefore still a big challenge. Although we implemented inductive teaching and learning methods in our courses for several years, we do not have a panacea. This paper aims to identify the remaining teaching obstacles in our Software Engineering courses with regard to the concrete teaching content. We present first ideas on how to overcome these teaching obstacles by the application of Augmented and/or Virtual Reality techniques with regard to the identified obstacles. Y1 - 2017 U6 - https://doi.org/10.1109/EDUCON.2017.7943067 SP - 1631 EP - 1635 ER - TY - CHAP A1 - Reuter, Rebecca A1 - Hauser, Florian A1 - Gold-Veerkamp, Carolin A1 - Mottok, Jürgen A1 - Abke, Jörg T1 - Towards a Definition and Identification of Learning Obstacles in Higher Software Engineering Education T2 - EDULEARN17 Proceedings, 9th International Conference on Education and New Learning Technologies, 3-5 July, 2017, Barcelona, Spain KW - Hochschuldidaktik KW - Software Engineering Y1 - 2017 SN - 978-84-697-3777-4 U6 - https://doi.org/10.21125/edulearn.2017.0943 SN - 2340-1117 SP - 10259 EP - 10267 ER - TY - CHAP A1 - Hauser, Florian A1 - Reiß, Markus A1 - Nivala, Markus A1 - Mottok, Jürgen A1 - Gruber, Hans T1 - Eye tracking applied: Visual expertise in code reviews T2 - 9th International Conference on Education and New Learning Technologies, EDULEARN17, 3-5 July, 2017, Barcelona, Spain, Proceedings Y1 - 2017 U6 - https://doi.org/10.21125/edulearn.2017.1084 SP - 379 EP - 389 ER - TY - CHAP A1 - Nivala, Markus A1 - Hauser, Florian A1 - Jossberger, Helen A1 - Reiß, Markus A1 - Mottok, Jürgen A1 - Gruber, Hans T1 - Detecting errors in program flow diagrams: Comparing novices and advanced programmers T2 - EARLI Biennial Conference 2017, 17th European Association for Research on Learning and Instruction, 29 August - 2 September, 2017 - University of Tampere, Finland Y1 - 2017 ER - TY - CHAP A1 - Reuter, Rebecca A1 - Kuhn, Martina A1 - Mottok, Jürgen T1 - A Two-Sided Approach of Applying Software Engineering Perspectives in Higher Education T2 - Teaching and Learning in a Digital World, ICL 2017, Proceedings of the 20th International Conference on Interactive Collaborative Learning - Volume 1 Y1 - 2017 SP - 460 EP - 467 ER - TY - CHAP A1 - Weiherer, Kerstin A1 - Osinski, Lukas A1 - Mottok, Jürgen T1 - Software-Based Triple Modular Redundancy with Fault-Tolerant Replicated Voters T2 - 32nd International Conference on Architecture of Computing Systems, ARCS Workshop 2019, 20-21 May 2019, Copenhagen, Denmark N2 - New computing-intensive applications such as assisted or highly automated driving are rapidly expanding the domain of safety-critical embedded systems, driven by the vision of the driverless car. This development makes it necessary to use high performance multi-core systems which are commercially available and provide more parallelism in terms of redundant execution units, however, at the cost of being less reliable. With the continuous down-scaling of semiconductor technology, computing hardware exhibits an increasing vulnerability against random hardware faults. Since these high-performance controller provide less or no hardware redundancy to ensure a safe execution of the application, software-only fault tolerance approaches are under current investigation. Our Scalable Software Support for Dependable Embedded Systems (S3DES) approach achieves fault tolerance by utilizing software-based triple modular redundancy for computational and optimized arithmetic encoded voter processes to ensure fault detection and error handling on application level. In S3DES voters are replicated to allow the compensation of voting failures. However, new challenges with regard to error propagation and multiple voting result outputs are introduced by this extension. We describe how mutual voter monitoring and threshold value checks could be used to establish a hierarchy among the replicated voters without re-introducing a reliability bottleneck in the sense of a single point of failure and resolve the aforementioned challenges. Y1 - 2019 UR - https://ieeexplore.ieee.org/abstract/document/8836210 SP - 1 EP - 8 ER - TY - CHAP A1 - Osinski, Lukas A1 - Mottok, Jürgen T1 - Control Flow Errors: A Discussion of Different Injection Strategies T2 - 32nd International Conference on Architecture of Computing Systems, ARCS Workshop 2019, 20-21 May 2019, Copenhagen, Denmark N2 - Among the available dependability assessment techniques, fault injection (FI) is widely adopted and strongly recommended by safety standards for the validation that functional and technical safety mechanisms are implemented correctly and effectively. The main challenge in fault injection assessments is the increasing complexity of system-on-chips as well as the increasing size of memory, which leads to enormous efforts to test every possible fault introduced to the system. Therefore, a number of publicly available fault injection frameworks utilize fault space pruning techniques to reduce the overall fault space and consequently the overall experiment duration. Most of the fault space pruning techniques mainly discuss the reduction of the number of data errors which have to be injected into registers and memory locations. However, control flow errors represent a further domain of possible errors on the application level. Usually for the evaluation of effectiveness of fault tolerance mechanisms against data errors, a single fault assumption at microarchitectural level (e.g. bit-flips) is assumed. In most cases, this assumption is equivalently applied to the program counter to investigate possible control flow errors. Due to this approach, the error space is consciously or unconsciously reduced to the possible erroneous jump targets that can be reached by a specific set of bit-flips in the program counter at a specified time during the program execution. This approach is considered valid regarding the corresponding fault assumption, but leads to negative effects on the significance of the injection and the resulting effectiveness of the tested fault tolerance mechanism. In this paper, we discuss different strategies for the analysis and injection of control flow errors and the resulting differences by considering the single fault assumption at microarchitectural and application level. Y1 - 2019 UR - http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=8836207&isnumber=8836190 SP - 1 EP - 7 ER - TY - CHAP A1 - Hauser, Florian A1 - Reuter, Rebecca A1 - Gruber, Hans A1 - Mottok, Jürgen T1 - Research competence: Modification of a questionnaire to measure research competence at universities of applied sciences T2 - IEEE Global Engineering Education Conference (EDUCON), 17-20 April 2018, Santa Cruz de Tenerife, Spain N2 - This paper deals with the validation and modification of the German questionnaire "F-Komp". In its original version, it was intended to measure university students' research competences. In the beginning of this study, there were only a few tools available which were reliable. For the purposes of this study, they were not suitable. At the same time, there was no validated version of the F-Komp available, which made the whole validation process for further usage necessary. This questionnaire is based on a structure, which consist of different skills and knowledge and is focused on measuring research competence in general. The validation and modification of the F-Komp is therefore the aim of our contribution as well as a revised version of the questionnaire. We proceeded an explorative factor and a reliability analysis to do a general evaluation of the tool. Some modifications were done in the questionnaire to make it more suitable to the requirements of technical oriented universities of applied sciences [5]. Our revised version is slightly longer and contains several items to gather data about the participants demographics. The modified questionnaire is based on a more appropriate factor structure. This structure is more practically oriented and pays attention to ethical issues. In future cases, this questionnaire will be used in research oriented courses to measure students' progress in acquiring the knowledge and methods which are necessary to perform as a scientist in different research areas. KW - research oriented teaching KW - research competence KW - competence model KW - modification of a questionnaire Y1 - 2018 U6 - https://doi.org/10.1109/EDUCON.2018.8363216 SP - 109 EP - 117 ER - TY - CHAP A1 - Schmid, Michael A1 - Mottok, Jürgen ED - Schoeberl, Martin ED - Hochberger, Christian ED - Uhrig, Sascha ED - Brehm, Jürgen ED - Pionteck, Thilo T1 - Asynchronous Critical Sections in Real-Time Multiprocessor Systems T2 - Architecture of Computing Systems - ARCS 2019, 32nd International Conference, Copenhagen, Denmark, May 20-23, 2019, Proceedings N2 - Sharing data across multiple tasks in multiprocessor systems has intensively been studied in the past decades. Various synchronization protocols, the most well-known being the Priority Inheritance Protocol or the Priority Ceiling Protocol, have been established and analyzed so that blocking times of tasks waiting to access a shared resource can be upper bounded. To the best of our knowledge, all of these protocols share one commonality: Tasks that want to enter a critical section, that is already being executed by another task, immediately get blocked. In this paper, we introduce the Asynchronous Priority Ceiling Protocol (A-PCP), which makes use of aperiodic servers to execute the critical sections asynchronously, while the calling task can continue its work on non-critical section code. For this protocol, we provide a worst-case response time analysis of the asynchronous computations, as well as necessary and sufficient conditions for a feasibility analysis of a set of periodic tasks using the proposed synchronization model on a system that preemptively schedules the tasks under the rate-monotonic priority assignment. Y1 - 2019 U6 - https://doi.org/10.1007/978-3-030-18656-2_5 SP - 56 EP - 67 PB - Springer CY - Cham ER - TY - CHAP A1 - Osinski, Lukas A1 - Mottok, Jürgen ED - Schoeberl, Martin ED - Hochberger, Christian ED - Uhrig, Sascha ED - Brehm, Jürgen ED - Pionteck, Thilo T1 - S 3DES - Scalable Software Support for Dependable Embedded Systems T2 - Architecture of Computing Systems - ARCS 2019, 32nd International Conference, Copenhagen, Denmark, May 20-23, 2019, Proceedings N2 - Scalable Software Support for Dependable Embedded Systems (S3DES) achieves fault tolerance by utilizing spatial software-based triple modular redundancy for computational and voter processes on application level. Due to the parallel execution of the replicas on distinct CPU cores it makes a step towards software-based fault tolerance against transient and permanent random hardware errors. Additionally, the compliance with real-time requirements in terms of response time is enhanced compared to similar approaches. The replicated voters, the introduced mutual voter monitoring and the optimized arithmetic encoding allow the detection and compensation of voter failures without the utilization of backward recovery. Fault injection experiments on real hardware reveal that S3DES can detect and mask all injected data and program flow errors under a single fault assumption, whereas an uncoded voting scheme yields approx. 12% silent data corruptions in a similar experiment. Y1 - 2019 U6 - https://doi.org/10.1007/978-3-030-18656-2_2 SP - 15 EP - 27 PB - Springer CY - Cham ER - TY - CHAP A1 - Renner, Sebastian A1 - Pozzobon, Enrico A1 - Mottok, Jürgen A1 - Hackenberg, Rudolf T1 - Benchmarking Software Implementations of 1st Round Candidates of the NIST LWC Project on Microcontrollers T2 - 3rd Lightweight Cryptography Workshop at NIST, Gaithersburg, USA N2 - This paper introduces a custom framework for benchmarking software implementations from the National Institute of Standards and Technology (NIST) Lightweight Cryptography (LWC) project on embedded devices. We present the design and core functions of the framework and apply it to various NIST LWC authenticated encryption with associated data (AEAD) ciphers. Altogether, we evaluate the speed of 213 submitted algorithm vari-ants on four different microcontroller units (MCUs), including 32 bit ARM and 8 bit AVR architectures. To allow a more meaningful comparison, we also conduct code size tests on all four boards and RAM utilization tests on one test platform. Y1 - 2019 UR - https://csrc.nist.gov/CSRC/media/Events/lightweight-cryptography-workshop-2019/documents/papers/benchmarking-software-implementations-lwc2019.pdf ER - TY - CHAP A1 - Rudolph, Alexander A1 - Voget, Stefan A1 - Mottok, Jürgen T1 - A consistent safety case argumentation for artificial intelligence in safety related automotive systems – An Evaluation of a New Conceptual Functional Safety Approach T2 - Embedded Real-Time Software and Systems Conference (ERST²), Jan 2018, Toulouse/France N2 - Regarding the actual automotive safety norms the use of artificial intelligence (AI) in safety critical environments like autonomous driving is not possible. This paper introduces a new conceptual safety modelling approach and a safety argumentation to certify AI algorithms in a safety related context. Therefore, a model of an AI-system is presented first. Afterwards, methods and safety argumentation are applied to the model, whereas it is limited to a specific subset of AI-systems, i.e. off-board learning deterministic neural networks in this case. Other cases are left over for future research. The result is a consistent safety analysis approach that applies state of the art safety argumentations from other domains to the automotive domain. This will enforce the adaptation of the functional safety norm ISO26262 to enable general AI methods in safety critical systems in future. Y1 - 2018 UR - https://hal.archives-ouvertes.fr/hal-02156048 ER - TY - CHAP A1 - Mottok, Jürgen A1 - Reichenberger, Marcus T1 - Use of Static Analysis and Coding Guidelines in embedded Systems Software T2 - 1st Applied Research Conference, ARC 2019, 8 July 2019, Regensburg Y1 - 2019 SN - 978-3-96409-182-6 SP - 571 EP - 578 PB - Pro BUSINESS ER - TY - CHAP A1 - Osinski, Lukas A1 - Mottok, Jürgen T1 - Das FORMUS³IC Forschungsvorhaben im Verbund – Vom Stand der Technik zu neuen Entwicklungen T2 - Embedded Software Engineering Kongress (ESE 2018), 3.-7.12.2018, Sindelfingen, Tagungsband Y1 - 2018 ER - TY - CHAP A1 - Soska, Alexander A1 - Mottok, Jürgen ED - Pivec, M. ED - Gründler, J. T1 - An Integrated Puzzle Game for Learning Programming Based on Students Syntactical Errors T2 - 11th European Conference on Game-Based Learning, Oct 5 - Oct 6, 2017, Graz N2 - Practical implementations are important for understanding the concepts and principles of programming. Self-employed coding encourages learners to acquire learning content and fosters the theory-practice transfer. Thereby, the earners face various difficulties and obstacles. Misconceptions and faults accompany the learners’ coding process and result in non-executable coding artefacts. The integrated compiler of programming environments provides information concerning error messages that indicate incorrect coding constructs. Usually due to unspecific and generic formulation, learners find it hard to understand these error messages. Yet these observable errors give valuable information about the learner’s coding behaviour and indicate current problems. These provide a link for adopted and appropriate learning assistance during the coding process. In this work in progress paper, we present first assumptions in assisting learners’ understanding and correction of programming errors by a game-based learning method. Our first approach focuses on the integration of a puzzle game into a programming environment. The game content adjusts to the error messages based on the analysis of the learner’s log file. We suggest that the integration of this approach rises the learner’s motivation to self-employed error handling and the quality of learning programming. Y1 - 2017 PB - Academic Conferences and Publishing International ER - TY - CHAP A1 - Langer, Tobias A1 - Osinski, Lukas A1 - Schmid, Michael A1 - Mottok, Jürgen T1 - Work-in-Progress: Real-Time Scheduling of Parallel Applications with Gang Scheduling T2 - International Conference on Architecture of Computing Systems (ARCS) Workshop, 9-12 April 2018, Braunschweig, Germany N2 - Future embedded systems demand increasingly more computation performance, which can only be provided by exploiting parallelism in real-time applications. Due to scheduling and scalability issues, parallelism still is an open issue especially in hard real-time systems. In this work-in-progress paper, we describe and discuss a hierarchical gang-scheduling based approach to address the scalability issue. We use gang scheduling to schedule tasks consisting of multiple kernel level threads. The execution budget provided by the kernel level threads is used for scheduling of user level threads using a lightweight threading library running in user space. Further, the first steps towards an implementation in the realtime operating system kernel Erika OS are described and possible benefits and risks of this approach are shown. Y1 - 2018 ER - TY - CHAP A1 - Bartel, Alexander A1 - Soska, Alexander A1 - Wolff, Christian A1 - Hagel, Georg A1 - Mottok, Jürgen ED - Burghardt, M. ED - Wimmer, R. ED - Wolff, Christian ED - Womser-Hacker, C. T1 - Entwicklung eines Manifests für spielifizierte Hochschullehre T2 - Mensch und Computer 2017, Tagungsband N2 - In dieser Veröffentlichung präsentieren die Autoren erste Ergebnisse Ihrer Forschungsarbeit an einem Manifest für spielifizierte Hochschullehre. Ausgehend von einer Literaturrecherche über den aktuellen Forschungsstand werden erste Auszüge der aktuellen Arbeit dargestellt, auf deren Basis ein aktiver wissenschaftlicher Diskurs angeregt werden soll. Y1 - 2017 U6 - https://doi.org/10.18420/muc2017-mci-0277 SP - 299 EP - 304 CY - Regensburg ER - TY - CHAP A1 - Knietzsch, Marco A1 - Muckelbauer, Daniel A1 - Reuter, Rebecca A1 - Mottok, Jürgen ED - Chova, L. G. ED - Martínez, A. L. ED - Torres, I. C. T1 - Experimental Verification of Indicated Benefits Of Integrating Augmented Reality into Academic Software Engineering Classes T2 - IATED, 11th International Conference of Education, Research and Innovation (ICERI 2018), 12-14 November 2018, Seville, Spain Y1 - 2018 SN - 978-84-09-05948-5 U6 - https://doi.org/10.21125/iceri.2018.1057 SN - 2340-1095 SP - 243 EP - 252 ER - TY - CHAP A1 - Jahn, Sabrina A1 - Gold-Veerkamp, Carolin A1 - Reuter, Rebecca A1 - Mottok, Jürgen A1 - Abke, Jörg T1 - Secure Software Engineering in academic education: students’ sreconceptions of it security T2 - 12th International Conference of Education, Research and Innovation (ICERI2019), 11-13 November 2019, Seville, Spain Y1 - 2019 U6 - https://doi.org/10.21125/iceri.2019.1624 SP - 6825 EP - 6834 ER - TY - CHAP A1 - Hauser, Florian A1 - Reuter, Rebecca A1 - Gegenfurtner, Andreas A1 - Gruber, Hans A1 - Mottok, Jürgen T1 - Eye movements in software modelling – what do they tell us about heuristics T2 - 12th International Conference of Education, Research and Innovation (ICERI 2019), Conference Proceedings, 2019, Seville (Spain) Y1 - 2019 SN - 978-84-09-14755-7 U6 - https://doi.org/10.21125/iceri.2019.1469 SP - 6064 EP - 6070 ER - TY - CHAP A1 - Müller, L. A1 - Jahn, Sabrina A1 - Reuter, Rebecca A1 - Mottok, Jürgen ED - Chova, L. G. ED - Martínez, A. L. ED - Torres, I. C. T1 - A Task Design Concept For A Virtual Classroom For Requirements Engineering Education T2 - ICERI 2018 Proceedings, Seville, Spain Y1 - 2018 U6 - https://doi.org/10.21125/iceri.2018.1216 SP - 911 EP - 920 ER - TY - CHAP A1 - Seidl, M. A1 - Krämer, Stefan A1 - Mottok, Jürgen T1 - Improving the reliability of an embedded real-time system by applying coded processing T2 - 4th Applied Research Conference, 5th July 2014, Ingolstadt Y1 - 2014 SN - 978-3-8440-2875-1 SP - 70 EP - 74 PB - Shaker CY - Aachen ER - TY - CHAP A1 - Seebauer, Stefan A1 - Jahn, Sabrina A1 - Mottok, Jürgen T1 - Escape Rooms for teaching IT-Security T2 - 12th International Conference of Education, Research and Innovation (ICERI2019), 11-13 November 2019, Seville, Spain Y1 - 2019 U6 - https://doi.org/10.21125/iceri.2019.1623 SP - 6815 EP - 6824 ER - TY - CHAP A1 - Schreistetter, Stefan A1 - Hauser, Florian A1 - Reuter, Rebecca A1 - Jahn, Sabrina A1 - Mottok, Jürgen T1 - Using Eye Tracking Data to analyze students’ tasks solving behavior in classroom contexts T2 - 12th International Conference of Education, Research and Innovation (ICERI 2019), Conference Proceedings, 2019, Seville (Spain) Y1 - 2019 SN - 978-84-09-14755-7 U6 - https://doi.org/10.21125/iceri.2019.1473 SN - 2340-1095 SP - 6087 EP - 6096 ER - TY - CHAP A1 - Hansch, G. A1 - Staudte, Ch. A1 - Gerhager, S. A1 - Hackenberg, Rudolf A1 - Mottok, Jürgen ED - Mottok, Jürgen ED - Ziemann, Olaf T1 - Migration path for secure and economic smart power grid devices with transitional smart metering support T2 - Applied Research Conference 2012 (ARC 2012), 25./26. June 2012 Nuremberg Y1 - 2012 SN - 2012 978-3-8440-1093-0 SP - 63 EP - 69 PB - Shaker CY - Aachen ER - TY - JOUR A1 - De, Sangita A1 - Niklas, Michael A1 - Brian, Rooney A1 - Mottok, Jürgen A1 - Brada, Premek T1 - Semantic Mapping of Component Framework Interface Ontologies for Interoperability of Vehicle Applications JF - Procedia Computer Science N2 - Over the past few years, ontology merging, and ontology semantic alignment has gained significant interest as research topics in automotive application domain for finding solutions to semantic data heterogeneity. To accomplish the complex and novel vehicle service requirements such as autonomous driving, V2X (Vehicle-to-Vehicle communication), etc. the automotive applications involve collaborations of several platform-specific data from heterogeneous enterprises component frameworks and consequently there has been increase in data interoperability issues. At the application component level, data interoperability relies on the semantic alignment or mapping between the various component framework interfaces data models represented as XML schemas (XSD). With the XML schemas being the preferred standard for the interface description exchange between most of the automotive application domain components, however, the data interoperability between the semantically equivalent but structurally different data constructs of multiple heterogeneous XSDs stands as a challenge in the absence of an ontology-based approach. To confront this crucial requirement for data interoperability and to increase in effect the reuse of existing components through their interfaces, we propose an approach to semantically map the various component framework interface data models when expressed as ontology schemas, based on the exploration of semantic synergies. The transformation between XSD and RDF (Resource Description Framework) schema representations and the use of queries over the ontology schemas for semantic mapping are demonstrated including a real-world case study. KW - component KW - interface KW - mapping KW - ontology KW - semantic Y1 - 2020 U6 - https://doi.org/10.1016/j.procs.2020.03.151 VL - 170 IS - 2 SP - 813 EP - 818 PB - Elsevier ER - TY - CHAP A1 - Renner, Sebastian A1 - Mottok, Jürgen ED - Trinitis, Carsten ED - Pionteck, Thilo T1 - Towards Key Management Challenges in the Smart Grid T2 - ARCS Workshop 2019 - 32nd International Conference on Architecture of Computing Systems, 20-21 May 2019, Copenhagen, Denmark N2 - The used technology in the power system is subject of great change. Through the use of smart devices, the systems in the power grid get interconnected between each other and remote networks. Especially the remote access to the critical smart grid environment involves new challenges in the area of security. To ensure the transmitted data and the access to the system is secured, cryptographic mechanisms have to be implemented. One critical part in this task is the management of cryptographic keys. This paper explains and defines a set of basic requirements for cryptographic key management in the smart grid. These requirements are derived from challenges present in common corporate environments. Then, basic approaches in the field of key management are stated and evaluated for the applicability in the power system. Different protocols for the implementation of key management strategies are shown and an assessment regarding their suitability for the defined requirements is conducted. KW - Cryptographic key management KW - smart grid security KW - post-quantum cryptography Y1 - 2019 UR - https://ieeexplore.ieee.org/document/8836205 SN - 978-3-8007-4957-7 PB - VDE-Verlag CY - Berlin ER - TY - CHAP A1 - De, Sangita A1 - Mottok, Jürgen A1 - Niklas, Michael A1 - Brada, Premek ED - Trinitis, Carsten ED - Pionteck, Thilo T1 - Semantic Synergy Exploration in Interface Description Models of Heterogeneous Vehicle Frameworks: Towards Automotive Meta Interface Description Model T2 - ARCS 2019: 32nd GI/ITG International Conference on Architecture of Computing Systems May 20 - 21, 2019, Technical University of Denmark, Copenhagen, Denmark Workshop, Proceedings N2 - This The vehicle is evolving to a complex network of heterogeneous subsystems of ECUs, sensors and actuators, each with different computational requirements. These sub-systems are connected via bus systems following different communication paradigms like e.g. signal based or service-oriented communications. This has led to the heterogeneous syntax of describing interfaces even though the semantics of the interfaces are similar. The wide variety of Interface Description Languages (IDLs) in automotive industry hinders partly with the efficient collaboration between different suppliers and the OEMs in the automotive industry. Given this wide variety of automotive IDLs, what could be more beneficial, from a software engineering point of view, is a generic automotive domain specific IDL that can satisfy all the fundamental requirements of the heterogeneous subsystems. This paper describes an approach to compare and correlate IDLs based on semantic similarities of the languages, considering the two aspects: application description and underlying message frameworks used in the different domains of given automotive subsystems. With the exploration of semantic synergies between the IDLs, various domain specific and domain-agnostic frameworks can be compared and correlated. The results can be generalized and abstracted to define a generic Meta IDL which could support use cases like e.g. domain-agnostic functional models and migration of software components between different kinds of automotive subsystems. Y1 - 2019 UR - https://ieeexplore.ieee.org/document/8836199 SN - 978-3-8007-4957-7 SP - 63 EP - 70 PB - VDE VERLAG CY - Berlin ER - TY - CHAP A1 - Thomeczek, Ludwig A1 - Attenberger, Andreas A1 - Kolb, Johannes A1 - Matoušek, Václav A1 - Mottok, Jürgen ED - Unger, Herwig T1 - Betrachtungen zu Latenzquellen und deren Beobachtung in POSIX-Systemen am Beispiel von Container-Runtimes T2 - Echtzeit 2019 N2 - Die am weitesten verbreiteten autonomen Systeme der Zukunft sind aller Voraussicht nach intelligente Fahrzeuge, welche selbständig im Straßenverkehr navigieren und mit der Umgebung interagieren. Diese neuen Funktionen erfordern den Einsatz von performanten Mehrkernprozessoren sowie von komplexen (POSIX-kompatiblen) Betriebssystemen. Gleichzeitig erfordert der Einsatz im Automobil hohe funktionale Sicherheit (ASIL-Level), was unter anderem robuste Echtzeiteigenschaften der verwendeten Hard- und Software voraussetzt. Den Echtzeiteigenschaften steht die erhöhte Komplexität mit neuen Quellen für nichtdeterministische Latenzen gegenüber. In diesem Paper präsentieren wir eine Übersicht über diese neuen Einflussfaktoren, und vermessen anschließend Containerlaufzeitumgebungen und deren Latenzverhalten. Wir zeigen dabei, das Netzwerkbrücken unter Last erheblichen Einfluss (Faktor 4–5) auf die Netzwerklatenz ausüben können. Y1 - 2019 SN - 978-3-658-27807-6 U6 - https://doi.org/10.1007/978-3-658-27808-3_12 VL - 35 SP - 109 EP - 118 PB - Springer Fachmedien Wiesbaden CY - Wiesbaden ER - TY - CHAP A1 - Thomeczek, Ludwig A1 - Attenberger, Andreas A1 - Kolb, Johannes A1 - Matoušek, Vaclav A1 - Mottok, Jürgen ED - Trinitis, Carsten ED - Pionteck, Thilo T1 - Measuring Safety Critical Latency Sources using Linux Kernel eBPF Tracing T2 - ARCS 2019: 32nd International Conference on Architecture of Computing Systems : workshop proceedings, May 20- 21, 2019, Technical University of Denmark, Copenhagen, Denmark Y1 - 2019 UR - https://ieeexplore.ieee.org/abstract/document/8836200 SN - 978-3-8007-4957-7 PB - VDE VERLAG GMBH CY - Berlin ER - TY - CHAP A1 - Jahn, Sabrina A1 - Weiss, Nils A1 - Akcakoca, Ugur A1 - Mottok, Jürgen ED - Gómez Chova, L. ED - López Martínez, A. ED - Candel Torres, I. T1 - Under The Hood - A Concept for Virtualized Automotive Security Education T2 - EDULEARN21: Proceedings N2 - In recent years, our society faced a massive interconnection of computer-based everyday objects, which opens these items for cyber-attacks. Dependent on the physical capabilities, successful attacks can vary from data exposure or a loss of functionality to a threat to life and limb. Connected- and autonomous vehicles are extremely safety-critical systems with a huge damage potential. This global trend, together with existing and upcoming regulations (ISO 270xx, ISO 21434, UNECE WP.29, UNECE R155), and the lack of qualified professionals create a tension field for the entire automotive industry. Hence, new education concepts for engineers of safety-critical and connected systems are necessary to secure our daily and future systems against cyber-attacks and raise awareness and knowledge of the topic of IT-Security. Existing automotive security education systems have one common problem: All systems are hardware-based and therefore have very steep learning curves for beginners. Hardware-based systems, in general, are expensive in their initial costs, require regular maintenance, and add diverse operational difficulties independent of the aspired education goal. Additionally, the global pandemic increased the necessity of virtual education concepts for security training in cyber-physical systems. Therefore, we present a novel concept for the education of cyber-security professionals for automotive systems based on discovery and problem-based learning in a virtual learning environment (VLE). Our concept contains individual exercises focusing on the topics of vulnerabilities and attacks in automotive networks and systems. Each exercise relates those topics to the corresponding security goals and countermeasures for mitigation. The learners work collaboratively in a self-contained manner within the VLE to acquire the necessary information to answer questions or find a solution to the given problem. To consider the heterogeneous background (e.g. knowledge, experience, preconceptions) of the learners, the topics can be presented in different difficulties, enabling an adaptable learning environment and different learning trajectories within the exercises. The concept is based on a VLE, consisting of automotive networks and components, which simulate the behavior of a vehicle. This environment provides a hands-on, "real-life" scenario, which allows discovery and problem-based learning in a realistic, but cheap and scalable education environment. Furthermore, virtualization removes common difficulties, always present in training on real hardware. This aims to decrease complexity, prevent learning obstacles related to hardware handling, and enables a location-independent learning environment. The target group of our education concept is Bachelor and Master students of computer science, engineering (e.g. electrical engineering, mechatronics), or similar studies, and (experienced) engineers from the industry. In summary, our publication contains two contributions. We present an adaptable virtual learning environment for automotive security education, combined with an educational concept based on discovery and problem-based learning techniques. The goals of our concept are the education of cyber-security professionals for safety-critical, connected automotive systems and the support of life-long learning reaching from academic education to training in the industry. KW - automotive systems KW - discovery learning KW - higher education KW - inductive teaching KW - problem-based learning KW - security education KW - virtual learning environment Y1 - 2021 SN - 978-84-09-31267-2 U6 - https://doi.org/10.21125/edulearn.2021.1231 SN - 2340-1117 SP - 6109 EP - 6118 ER - TY - JOUR A1 - Schmid, Michael A1 - Fritz, Florian A1 - Mottok, Jürgen T1 - Fine-Grained Parallel Applications in Real-Time Multiprocessor Systems JF - Journal of Systems Architecture N2 - Lately, parallel task models have received much attention in the development of real-time multiprocessor systems, as they allow highly compute-intensive tasks to have shorter deadlines which is very much required in modern reactive systems. However, missing modularity and portability can make parallel programming a cumbersome endeavor. As a consequence, compute-intensive sectors in the desktop and server segment have relied on parallelism frameworks such as Intel Threading Building Blocks, Cilk and OpenMP. These parallelism frameworks, however, are optimized for decent average case performance and consequently, do not meet the strict requirements imposed by real-time systems. In this paper, we present a proof-of-concept parallelism framework which was implemented in particular for soft real-time systems and having tight timing and safety requirements of such critical systems in mind. The proposed runtime system implements static memory allocation in a work-stealing environment that conforms to the strict space and tight probabilistic time bounds of work-stealing schedulers. Furthermore, we evaluate the performance of this framework by conducting multiprogrammed benchmarks on a real-time embedded multicore architecture. KW - Real-time KW - Work-stealing KW - Thread pool KW - Task model KW - Parallel programming Y1 - 2021 U6 - https://doi.org/10.1016/j.sysarc.2022.102393 VL - 124 PB - Elsevier ER - TY - JOUR A1 - Weiss, Nils A1 - Pozzobon, Enrico A1 - Mottok, Jürgen A1 - Matoušek, Václav T1 - Automated Reverse Engineering of CAN Protocols JF - Neural Network World N2 - Car manufacturers define proprietary protocols to be used inside their vehicular networks, which are kept an industrial secret, therefore impeding independent researchers from extracting information from these networks. This article describes a statistical and a neural network approach that allows reverse engineering proprietary controller area network (CAN)-protocols assuming they were designed using the data base CAN (DBC) file format. The proposed algorithms are tested with CAN traces taken from a real car. We show that our approaches can correctly reverse engineer CAN messages in an automated manner. Y1 - 2021 U6 - https://doi.org/10.14311/NNW.2021.31.015 SN - 1210-0552 VL - 31 IS - 4 SP - 279 EP - 295 ER - TY - GEN A1 - Stark, T. A1 - Schreistetter, Stefan A1 - Reuter, R. A1 - Hauser, Florian A1 - Holmqvist, K. A1 - Mottok, Jürgen A1 - Gruber, Hans T1 - Learning from Gaze: Eye Movement Modeling Examples in Software Engineering Education T2 - Earli Book of Abstracts Y1 - 2021 UR - https://earli.org/assets/files/BOA-2021.pdf SP - 291 PB - Earli ER - TY - CHAP A1 - Studt, Reimer A1 - Weiß, Florian A1 - Mottok, Jürgen A1 - Weiss, Florian A1 - Mottok, Jürgen T1 - An engineering approach to developing lecture material for new study courses T2 - 2014 IEEE Global Engineering Education Conference (EDUCON), 3-5 April 2014, Istanbul, Turkey N2 - Professional software development is a complex task with many inputs and a complex output. In order to handle complex topics as software or complex engineering projects, structured processes as the V-model or iterative development processes exist. Similarly, the development of a software engineering lecture is a task with many inputs, and a complex output. A structured and methodological approach to the development of a lecture is presented, which applies the same principles as used in the development of software. KW - biomedical engineering KW - competence model KW - computer science education KW - Education KW - Insulin KW - Knowledge engineering KW - lecture development KW - Materials KW - Software KW - Software engineering KW - Unified modeling language Y1 - 2014 U6 - https://doi.org/10.1109/EDUCON.2014.6826153 SP - 592 EP - 597 PB - IEEE ER - TY - CHAP A1 - Kopp, Felix A1 - Köhler, Thorsten A1 - Mottok, Jürgen ED - Ivanov, Artem ED - Bicker, Marc ED - Patzelt, Peter T1 - Bildgebende Verfahren zur dreidimensionalen Rekonstruktion aus Bildsequenzen basierend auf der Bundler SFM Toolchain T2 - 4. Landshuter Symposium Mikrosystemtechnik : Mikrosystemtechnik als Schlüsseltechnologie der Systemintegration, Tagungsband zum Symposium 12./13. März 2014, Hochschule Landshut N2 - Vorgestellt wird der Structure from Motion (SFM)Toolchain Bundler zur Erzeugung von Punktwolken aus unkalibrierten Kameraaufnahmen und deren Optimierungsmöglichkeiten durch zeitnahe Verfahren zur Interessenpunktextraktion. Das Extrahieren markanter Punkte aus Bildern beinhaltet eines der zeitintensivsten sowie herausforderndsten Aufgaben im dreidimensionalen Rekonstruktionsprozess. Vor allem im Hinblick auf die Integration von Structure from Motion Verfahren auf eingebettete Systeme sind Rechenzeit und Speicherverbrauch von hohem Interesse. Für dreidimensionale Rekonstruktionsalgorithmen ist das Finden akkurater Punktkorrespondenzen von hoher Priorität. Die Anforderungen an Punktdetektor, -deskriptor und -matcher sind dementsprechend hoch. Untersucht wurden die Ansätze zur Interessenpunktextraktion. Hierzu gehören, der von der Bundler SFM Toolchain genutzte, Scale-invariant feature transform (SIFT) sowie Speeded Up Robust Features (SURF), Binary Robust Invariant Scalable Keypoints (BRISK) und Fast Retina Keypoint (FREAK). Es wird gezeigt, dass das Ersetzen von SIFT in der Toolchain vor allem durch die binären Deskriptoren BRISK und FREAK zu wesentlich kürzeren Laufzeiten führen kann. Dies ist vor allem für eingebettete Systeme mit eingeschränkter Rechenleistung von Bedeutung. In Bezug auf die Genauigkeit der gefundenen Punktkorrespondenzen übertreffen sowohl FREAK als auch BRISK die nicht binären Ansätze im Anwendungsprofil. Zur Beschreibung von Interessenpunkten sind die binären Ansätze eine sinnvolle Optimierungsmöglichkeit hinsichtlich Laufzeit und Genauigkeit, während der in BRISK enthaltene Detektor nicht an die Performance der nicht binären Alternativen herankommt. Insgesamt betrachtet wurden die besten Ergebnisse (Laufzeit und Genauigkeit) mit den Kombinationen SURF/FREAK und SURF/BRISK erreicht. Die evaluierten Algorithmen(SIFT,SURF,BRISK,FREAK) sollen künftig in der Umgebung einer kompletten 3D-Rekonstruktions-Toolchain getestet und ausgewertet werden. Hierbei ist auch auf die Abhängigkeit von verschiedenen Matching-Verfahren zu achten. Darüber hinaus sollen weitere Optimierungsmöglichkeiten für Anwendungen basierend auf Bündelausgleichung untersucht werden. KW - Bildfolge KW - Bildgebungsverfahren KW - Bildrekonstruktion KW - Bündelung KW - dreidimensionale Struktur KW - Oberflächenrekonstruktion Y1 - 2014 SN - 978-3-9812696-5-9 SP - 118 EP - 125 CY - Landshut ER - TY - CHAP A1 - Bayer, Michael A1 - Noebauer, Josef A1 - Mottok, Jürgen T1 - Weiterentwicklung eines portablen OSEK-OS basierten Echtzeitbetriebssystems zu einem konfigurierbaren AUTOSAR-OS T2 - 4. Landshuter Symposium Mikrosystemtechnik, Mikrosystemtechnik als Schlüsseltechnologie der Systemintegration, Tagungsband zum Symposium 12./13. März 2014, Hochschule Landshut N2 - AUTOSAR spezifiziert ein statisches Echtzeitbetriebssystem (AUTOSAR-OS), welches auf die Bedürfnisse der Automobilindustrie zugeschnitten ist. Dabei stellt die AUTOSAR-OS-Spezifikation im Wesentlichen eine Weiterentwicklung von OSEK-OS dar. Die Unterschiede zu einem OSEK-OS sind im Wesentlichen eine erweiterte Programmierschnittstelle für Counter, Schedule Tables zur Abbildung komplexer zeitgesteuerter Abläufe und Stack Monitoring. Der Scheduler arbeitet prioritätsbasiert und unterstützt unterbrechbare und nicht unterbrechbare Tasks. Eine Ressourcenverwaltung mit Priority Ceiling Protokoll verhindert Deadlocks und Prioritäteninversion. Tasks sind entweder als "Basic Tasks" oder "Extended Tasks" konfiguriert. Nach einer kurzen Vorstellung der OS-Spezifikation wird eine darauf basierte Architektur für das Betriebssystem hergeleitet. Die konkrete Implementierung ist aufgeteilt in einen konfigurationsabhängigen Teil und einen statischen Quellcodeteil. Der konfigurationsabhängige Teil wird von einem Quellcodegenerator erzeugt. Der statische Teil wird in einer Schichtenarchitektur erstellt, um eine Trennung zwischen plattformabhängigem und plattformunabhängigem Quellcode zu erreichen, da die hierfür vorgesehene AUTOSAR-Methode nicht ausreicht. Die Portierung des OS auf eine neue Hardwareplattform zeigt, dass nur die plattormabhängige Quellcodeschicht des Betriebssystems geändert werden muss. Bei der Validierung des Betriebssystems wurde neben einem funktionellen Test auch die Performance für charakteristische Aufgaben, wie beispielsweise einem Kontextwechsel, gemessen. Diese Werte werden mit einem kommerziellen, stark optimierten AUTOSAR-OS verglichen. KW - Auftragsverwaltung (DV) KW - Automobilindustrie KW - Echtzeitbetriebssystem KW - Echtzeitsystem KW - eingebettetes System KW - Quellencodierung KW - Systemarchitektur KW - Task-Management KW - Validierung Y1 - 2014 SN - 978-3-9812696-5-9 SP - 154 EP - 161 CY - Landshut ER - TY - CHAP A1 - Thomeczek, Ludwig A1 - Attenberger, Andreas A1 - Matoušek, Václav A1 - Mottok, Jürgen T1 - Latenzen von POSIX Betriebssystemen im Kontext von Hypervisoren in Real-Time Systemen T2 - Echtzeit und Sicherheit - Echtzeit 2018, Fachtagung des gemeinsamen Fachausschusses Echtzeitsysteme von Gesellschaft für Informatik e.V. (GI), VDI/VDE-Gesellschaft für Mess- und Automatisierungstechnik (GMA) und Informationstechnischer Gesellschaft im VDE (ITG), Boppard, 15. und 16. November 2018 N2 - Neu eingeführte Funktionen in der Automobilindustrie, wie zum Beispiel das autonome Fahren, erfordern den Einsatz von performanten Mehrkernprozessoren sowie von komplexen (POSIXkompatiblen) Betriebssystemen. Im Rahmen des branchenspezifischen Preisdrucks kommt es zudem zu einer Konsolidierung von Steuergeräten. Gleichzeitig erfordert der Einsatz im Automobil hohe funktionale Sicherheit (ASIL-Level), was unter anderem robuste Echtzeiteigenschaften der verwendeten Hard- und Software voraussetzt. Als Folge dessen werden zur Trennung von harten und weichen Echtzeitsystemen auf derselben Hardware Hypervisoren eingesetzt. Dieses Paper beleuchtet die Latenzauswirkungen diverser Softwarekonfigurationen auf Hardware der nächsten Generation mithilfe eines vorgestellten Testsetups und dessen Ergebnissen. Y1 - 2018 SN - 978-3-662-58095-0 SN - 978-3-662-58096-7 U6 - https://doi.org/10.1007/978-3-662-58096-7_11 SP - 99 EP - 108 ER - TY - JOUR A1 - Joseph, Saskia A1 - Schumm, Michael A1 - Rummel, Otmar A1 - Soska, Alexander A1 - Renschke, Michael A1 - Mottok, Jürgen A1 - Niemetz, Michael A1 - Schroll-Decker, Irmgard T1 - Teaching finite state machines with case method and role play JF - 2014 IEEE Global Engineering Education Conference (EDUCON 2014) : Istanbul, Turkey, 3 - 5 April 2014 N2 - The professional requirements in Software Engineering have become highly volatile due to the complexities of project development and rapid and innovative changes occurring in the field. Therefore, the development of inter-personal and social competences has gained central importance in the training of software developers. This paper will present a concept allowing to acquire competences by using Case Method and Role Play as instruments in several lectures of Software Engineering. By approaching the issue of competence acquisition on a technical as well as on an educational and social level, life-long learning is facilitated and supported. KW - Case Method KW - competences KW - learning arrangement KW - life-long learning KW - Role Play Y1 - 2013 U6 - https://doi.org/10.1109/EduCon.2013.6530275 SP - 1302 EP - 1305 PB - IEEE ER - TY - CHAP A1 - De, Sangita A1 - Niklas, Michael A1 - Rooney, Brian A1 - Mottok, Jürgen A1 - Brada, Premek T1 - Towards Semantic model-to-model Mapping of Cross-Domain Component Interfaces for Interoperability of Vehicle Applications : An Approach towards Synergy Exploration T2 - MDE4IoT & ModComp 2019: Model-Driven Engineering for the Internet of Things (MDE4IoT) & Interplay of Model-Driven and Component-Based Software Engineering (ModComp); joint proceedings of the Workshop on Model-Driven Engineering for the Internet of Things (MDE4IoT) & of the Workshop on Interplay of Model-Driven and Component-Based Software Engineering (ModComp); co-located with the IEEE/ACM 22nd International Conference on Model Driven Engineering Languages and Systems (MODELS 2019), Munich, Germany, September 15 and 17, 2019 N2 - With the increase in demand of services in the automotive industry, automotive enterprises prefer to collaborate with other qualified cross-domain partners to provide complex automotive functions (or services), such as autonomous driving, OTA (Over The Air) vehicle update, V2X (Vehicle-to-Vehicle communication), etc. One key element in cross-domain enterprise collaboration is the mutual agreement between interfaces of software components. In this context, model-to-model mappings of software component models of heterogeneous frameworks for automotive services and to explore the synergies in their interface semantics, have become an essential factor in improving the interoperability among the automotive and other cross-domain enterprises. However, one of the challenges in achieving cross-domain component interface model-to-model mappings at an application level lies in detecting the interface semantics and the semantic relations that are conveyed in different component models in different frameworks. This paper addresses this challenge using a Model Driven Architecture (MDA) based analytical approach to explore interface semantic synergies in the cross-domain component meta-models that are used for automotive services. The approach applies manual semantic checking measurements at an application interface level to understand the meanings and relations between the different meta-model entities of cross-domain framework software components. In this research, we attempt to ensure that interface description models of software components from heterogeneous frameworks can be compared, correlated and re-used for automotive services based on semantic synergies. We have demonstrated our approach using component meta-models from cross-domain enterprises, that are used for the automotive application domain. Y1 - 2019 UR - https://ceur-ws.org/Vol-2442/paper8.pdf U6 - https://doi.org/10.13140/RG.2.2.28765.15840 PB - RWTH Aachen CY - Aachen ER - TY - CHAP A1 - Maier, Robert A1 - Mottok, Jürgen ED - Trapp, Mario ED - Saglietti, Francesca ED - Spisländer, Marc ED - Bitsch, Friedemann T1 - BayesianSafety - an Open-Source Package for Causality-Guided, Multi-Model Safety Analysis T2 - Computer Safety, Reliability, and Security, 41st International Conference (SAFECOMP 2022): Munich, Germany, September 6–9, 2022, Proceedings T2 - Lecture notes in computer science ; 13414 N2 - Development and verification of modern, dependable automotive systems require appropriate modelling approaches. Classic automotive safety is described by the normative regulations ISO 26262, its relative ISO/PAS 21448, and their respective methodologies. In recent publications, an emerging demand to combine environmental influences, machine learning, or reasoning under uncertainty with standard-compliant analysis techniques can be noticed. Therefore, adapting established methods like FTA and proper tool support is necessary. We argue that Bayesian Networks (BNs) can be used as a central component to address and merge these demands. In this paper, we present our Open-Source Python package BayesianSafety. First, we review how BNs relate to data-driven methods, model-to-model transformations, and causal reasoning. Together with FTA and ETA, these models form the core functionality of our software. After describing currently implemented features and possibilities of combining individual modelling approaches, we provide an informal view of the tool’s architecture and of the resulting software ecosystem. By comparing selected publicly available safety and reliability analysis libraries, we outline that many relevant methodologies yield specialized implementations. Finally, we show that there is a demand for a flexible, unifying analysis tool that allows researching system safety by using multi-model and multi-domain approaches. KW - Package BayesianSafety KW - Causality KW - Bayesian Networks KW - Event Tree Analysis KW - Fault Tree Analysis Y1 - 2022 U6 - https://doi.org/10.1007/978-3-031-14835-4_2 SP - 17 EP - 30 PB - Springer Nature CY - Cham ER - TY - CHAP A1 - Maier, Robert A1 - Grabinger, Lisa A1 - Urlhart, David A1 - Mottok, Jürgen ED - Seguin, Christel ED - Zeller, Marc ED - Prosvirnova, Tatiana T1 - Towards Causal Model-Based Engineering in Automotive System Safety T2 - Model-Based Safety and Assessment, 8th International Symposium, IMBSA 2022: Munich, Germany, September 5–7, 2022, Proceedings N2 - Engineering is based on the understanding of causes and effects. Thus, causality should also guide the safety assessment of complex systems such as autonomous driving cars. To ensure the safety of the intended functionality of these systems, normative regulations like ISO 21448 recommend scenario-based testing. An important task here is to identify critical scenarios, so-called edge and corner cases. Data-driven approaches to this task (e.g. based on machine learning) cannot adequately address a constantly changing operational design domain. Model-based approaches offer a remedy – they allow including different sources of knowledge (e.g. data, human experts) into safety considerations. With this paper, we outline a novel approach for ensuring automotive system safety. We propose to use structural causal models as a probabilistic modelling language to combine knowledge about an open-context environment from different sources. Based on these models, we investigate parameter configurations that are candidates for critical scenarios. In this paper, we first discuss some aspects of scenario-based testing. We then provide an informal introduction to causal models and relate their development lifecycle to the established V-model. Finally, we outline a generic workflow for using causal models to identify critical scenarios and highlight some challenges that arise in the process. Y1 - 2022 U6 - https://doi.org/10.1007/978-3-031-15842-1_9 SP - 116 EP - 129 PB - Springer Nature CY - Cham ER - TY - CHAP A1 - De, Sangita A1 - Mottok, Jürgen A1 - Brada, Premek ED - Miraz, M.H. ED - Southall, G. ED - Ali, M. ED - Ware, A. T1 - Evaluation of Semantic Interoperability of Automotive Service API Models Based on Metamodels Similarity Metrics Using a Semi-automated Approach T2 - iCETiC 2022 : 5th International Conference on Emerging Technologies in Computing 2022: Aug 15, 2022 - Aug 16, 2022, Chester, UK N2 - In recent years, mapping of application software components’ ontologies semantically emerged as a big research challenge in automotive application domain that manipulates several cross-enterprise synergy knowledge application frameworks. The same knowledge formalized by different experts in different vehicle application frameworks leads to heterogeneous representations of components’ interface data. Consequently, this causes the most daunting impediment in semantic interoperability between the service components in cooperative automotive systems. From a modeling perspective, in the absence of standardized domain-based unified modeling techniques, the orchestration and resolution of semantic data interoperability between various vehicle application frameworks’ components’ interface models remain a challenge. However, this challenge could be addressed using ontological metamodeling by specifying semantic associations between components’ interface model concepts based on the domain knowledge. Apart from the semantic mapping of interface ontological metamodels, this work also defines quality metrics to determine the degree of semantic alignment achieved between the various interface ontologies. Additionally, to reduce development time and cost towards semantic interoperability, this work proposes a semi-automated plugin tool for the applicability of the evaluated quality metrics to semantic mapping of real-world components’ interface models. KW - Framework KW - Interface KW - Metamodel KW - Metrics KW - Ontology KW - Semantic Y1 - 2023 U6 - https://doi.org/10.1007/978-3-031-25161-0_2 SP - 14 EP - 28 PB - Springer CY - Cham ER - TY - CHAP A1 - Renner, Sebastian A1 - Pozzobon, Enrico A1 - Mottok, Jürgen ED - Li, Wenjuan ED - Furnell, Steven ED - Meng, Weizhi T1 - The Final Round: Benchmarking NIST LWC Ciphers on Microcontrollers T2 - Attacks and Defenses for the Internet-of-Things, 5th International Workshop, ADIoT 2022: Copenhagen, Denmark, September 30, 2022, Revised Selected Papers N2 - In this work, we present our benchmarking results for the ten finalist ciphers of the Lightweight Cryptography (LWC) project initiated by National Institute of Standards and Technology (NIST). We evaluate the speed and code size of various software implementations on five different platforms featuring four different architectures. Moreover, we benchmark the dynamic memory utilization of the remaining NIST LWC algorithms on one 32-bit ARM controller. We describe our test cases and methodology and provide some information regarding the design and properties of the finalists before showing and discussing our results. Altogether, we evaluated almost 300 implementations of the 3rd round candidates and pick the most appropriate and best (primary) implementation of each cipher for our comparisons. We include a variant of AES-GCM in our benchmarking in order to be able to compare the state-of-the-art to the novel LWC ciphers. Our research gives an overview over the performance of the latest software implementations of the NIST LWC finalists and shows under which circumstances which candidate is performing the best in our individual test cases. Additionally, we make all benchmarking results, the code for our test framework and every tested implementation available to the public to ensure a transparent testing process. Y1 - 2022 SN - 978-3-031-21311-3 U6 - https://doi.org/10.1007/978-3-031-21311-3_1 SP - 1 EP - 20 PB - Springer Nature CY - Cham ER - TY - CHAP A1 - Maier, Robert A1 - Mottok, Jürgen T1 - Causality and Functional Safety - How Causal Models Relate to the Automotive Standards ISO 26262, ISO/PAS 21448, and UL 4600 T2 - 27th International Conference on Applied Electronics (AE): 06-07 September 2022, Pilsen, CZ N2 - With autonomous driving, the system complexity of vehicles will increase drastically. This requires new approaches to ensure system safety. Looking at standards like ISO 26262 or ISO/PAS 21448 and their suggested methodologies, an increasing trend in the recent literature can be noticed to incorporate uncertainty. Often this is done by using Bayesian Networks as a framework to enable probabilistic reasoning. These models can also be used to represent causal relationships. Many publications claim to model cause-effect relations, yet rarely give a formal introduction of the implications and resulting possibilities such an approach may have. This paper aims to link the domains of causal reasoning and automotive system safety by investigating relations between causal models and approaches like FMEA, FTA, or GSN. First, the famous “Ladder of Causation” and its implications on causality are reviewed. Next, we give an informal overview of common hazard and reliability analysis techniques and associate them with probabilistic models. Finally, we analyse a mixed-model methodology called Hybrid Causal Logic, extend its idea, and build the concept of a causal shell model of automotive system safety. KW - Causality KW - Reliability KW - Functional Safety Y1 - 2022 U6 - https://doi.org/10.1109/AE54730.2022.9920053 PB - IEEE ER - TY - CHAP A1 - De, Sangita A1 - Niklas, M. A1 - Brada, Premek A1 - Mottok, Jürgen T1 - Model Transformation of Application Software Component from Classic to Adaptive AUTOSAR: An Approach to Migrate Software Components T2 - SEAA 2018, the 44th EUROMICRO Conference on Software Engineering and Advanced Applications, August 29 - 31 2018, Prague, Czech Republic Y1 - 2018 SN - 978-3-902457-50-9 ER - TY - CHAP A1 - Hauser, Florian A1 - Grabinger, Lisa A1 - Mottok, Jürgen A1 - Gruber, Hans T1 - Visual Expertise in Code Reviews: Using Holistic Models of Image Perception to Analyze and Interpret Eye Movements T2 - ETRA '23: 2023 Symposium on Eye Tracking Research and Applications, Tubingen Germany 30 May 2023- 2 June 2023 N2 - This study uses holistic models of image perception to analyze and interpret eye movements during a code review. 23 participants (15 novices and 8 experts) take part in the experiment. The subjects’ task is to review six short code examples in C programming language and identify possible errors. During the experiment, their eye movements are recorded by an SMI 250 REDmobile. Additional data is collected through questionnaires and retrospective interviews. The results implicate that holistic models of image perception provide a suitable theoretical background for the analysis and interpretation of eye movements during code reviews. The assumptions of these models are particularly evident for expert programmers. Their approach can be divided into different phases with characteristic eye movement patterns. It is best described as switching between scans of the code example (global viewing) and the detailed examination of errors (focal viewing). Y1 - 2023 U6 - https://doi.org/10.1145/3588015.3589189 SP - 1 EP - 7 PB - ACM ER - TY - CHAP A1 - Hauser, Florian A1 - Staufer, Susanne A1 - Grabinger, Lisa A1 - Röhrl, Simon A1 - Mottok, Jürgen ED - Gómez Chova, Luis ED - González Martínez, Chelo ED - Lees, Joanna T1 - On the analysis of student learning strategies: using the LIST-K questionnaire ro generate ai-based individualized learning paths T2 - Proceedings of the 16th annual International Conference of Education, Research and Innovation (ICERI 2023), Seville, Spain, 11/13/2023 - 11/14/2023 N2 - This paper presents the results of a data collection with the LIST-K questionnaire. This questionnaire measures students’ learning strategies and shows which strategies are particularly dominant or rather weak. Learning strategies have long been a major area of research in educational science and psychology. In these disciplines, learning strategies are understood as intentional behaviors and cognitive skills that learners employ to effectively complete learning tasks, by selecting, acquiring, organizing, and integrating information into their existing knowledge for long-term retention. The LIST-K, developed by Klingsieck in 2018, was chosen for accessing learning strategies due to its thematic suitability, widespread use, and test economy. It covers a total of four main categories (i.e., cognitive strategies, metacognitive strategies, management of internal resources, and management of external resources), each of which are subdivided into further subscales. With a total of 39 items answered via a 5-step Likert scale, the LIST-K can cover the topic relatively comprehensively and at the same time be completed in a reasonable amount of time of approximately 10 minutes. The LIST-K was used as part of a combined data collection along with other questionnaires on their personal data, their preferences regarding certain learning elements, their learning style (i.e. the ILS), and personality (i.e. the BFI-10). A total of 207 students from different study programs participated via an online survey created using the survey tool "LimeSurvey". Participation in the study was voluntary, anonymously, and in compliance with the GDPR. Overall, the results of the LIST-K show that students are willing to work intensively on relevant topics intensively and to perform beyond the requirements of the course seeking additional learning material. At the same time, however, it is apparent that the organization of their own learning process could still be improved. For example, students start repeating content too late (mean=2.70; SD=0.92) and do not set goals for themselves and do not create a learning plan (mean=3.19; SD=0.90). They also learn without a schedule (mean=2.23; SD=0.97) and miss opportunities to learn together with other students (mean=3.17; SD=0.94). The findings of the data collection will be used to create an AI-based adaptive learning management system that will create individualized learning paths for students in their respective courses. From the results of the LIST-K, it appears that the adaptive learning management system should primarily support organizational aspects of student learning. Even small impulses (an individual schedule of when to learn what or a hierarchical structuring of the learning material) could help students to complete their courses more successfully and improve their learning. Y1 - 2023 U6 - https://doi.org/10.21125/iceri.2023.1147 SP - 4611 EP - 4620 PB - IATED ER - TY - CHAP A1 - Bittner, Dominik A1 - Ezer, Timur A1 - Grabinger, Lisa A1 - Hauser, Florian A1 - Mottok, Jürgen ED - Gómez Chova, Luis ED - González Martínez, Chelo ED - Lees, Joanna T1 - Unveiling the secrets of learning styles: decoding eye movements via machine learning T2 - Proceedings of the 16th annual International Conference of Education, Research and Innovation (ICERI 2023), Seville, Spain, 11/13/2023 - 11/14/2023 N2 - Universities are faced with a rising number of dropouts in recent years. This is largely due to students' limited capability of finding individual learning paths through various course materials. However, a possible solution to this problem is the introduction of adaptive learning management systems, which recommend tailored learning paths to students – based on their individual learning styles. For the classification of learning styles, the most commonly used methods are questionnaires and learning analytics. Nevertheless, both methods are prone to errors: questionnaires may give superficial answers due to lack of time or motivation, while learning analytics do not reflect offline learning behavior. This paper proposes an alternative approach to classify students' learning styles by integrating eye tracking in combination with Machine Learning (ML) algorithms. Incorporating eye tracking technology into the classification process eliminates the potential problems arising from questionnaires or learning analytics by providing a more objective and detailed analysis of the subject's behavior. Moreover, this approach allows for a deeper understanding of subconscious processes and provides valuable insights into the individualized learning preferences of students. In order to demonstrate this approach, an eye tracking study is conducted with 117 participants using the Tobii Pro Fusion. Using qualitative and quantitative analyses, certain patterns in the subjects' gaze behavior are assigned to their learning styles given by the validated Index of Learning Styles (ILS) questionnaire. In short, this paper presents an innovative solution to the challenges associated with classifying students' learning styles. By combining eye tracking data with ML algorithms, an accurate and insightful understanding of students' individual learning paths can be achieved, ultimately leading to improved educational outcomes and reduced dropout rates. Y1 - 2023 SN - 978-84-09-55942-8 U6 - https://doi.org/10.21125/iceri.2023.1291 SP - 5153 EP - 5162 PB - IATED ER - TY - CHAP A1 - Ezer, Timur A1 - Greiner, Matthias A1 - Grabinger, Lisa A1 - Hauser, Florian A1 - Mottok, Jürgen ED - Gómez Chova, Luis ED - González Martínez, Chelo ED - Lees, Joanna T1 - Eye tracking al technology in education; data quality analysis and improvements T2 - Proceedings of the 16th annual International Conference of Education, Research and Innovation (ICERI 2023), Seville, Spain, 11/13/2023 - 11/14/2023 N2 - Eye tracking has proven to be a powerful tool in a variety of empirical research areas; hence, it is steadily gaining attention. Driven by the expanding frontiers of Artificial Intelligence and its potential for data analysis, eye tracking technology offers promising applications in diverse fields, from usability research to cognitive research. The education sector in particular can benefit from the increased use of eye tracking technology - both indirectly, for example by studying the differences in gaze patterns between experts and novices to identify promising strategies, and directly by using the technology itself to teach in future classrooms. As with any empirical method, the results depend directly on the quality of the data collected. That raises the question of which parameters educators or researchers can influence to maximize the data quality of an eye tracker. This is the starting point of the present work: In an empirical study of eye tracking as an (educational) technology, we systematically examine factors that influence the data quality, such as illumination, sampling frequency, and head orientation - parameters that can be varied without much additional effort in everyday classroom or research use - using two human subjects, an artificial face, and the Tobii Pro Spectrum. We rely on metrics derived from the raw gaze data, such as accuracy or precision, to measure data quality. The obtained results derive practical advice for educators and researchers, such as using the lowest sampling frequency appropriate for a certain purpose. Thereby, this research fills a gap in the current understanding of eye tracker performance and, by offering best practices, enables researchers or teachers to produce data of the highest quality possible and therefore best results when using eye trackers in laboratories or future classrooms. Y1 - 2023 U6 - https://doi.org/10.21125/iceri.2023.1127 SP - 4500 EP - 4509 PB - IATED ER - TY - INPR A1 - Heberl, Michael A1 - Withelm, Christian A1 - Kaul, Anja A1 - Rank, Daniel A1 - Sterner, Michael T1 - Prospective Life Cycle Assessment of Biological Methanation in a Trickle-Bed Pilot Plant and a Potential Scale-Up N2 - In this study, a pilot-scale trickle-bed reactor for biological methanation and various scale-up scenarios for 2023 and 2050 were investigated using LCA. A best- and worst-case scenario for technology development until 2050 was evolved using cross consistency analysis and morphological field, based on which the data for the ecological models were determined.The results show that the plant scale-up has a very positive effect on the ecological consequences of methanation. In the best-case scenario, the values are a factor of 23-780 lower than those of the actual plant today. A hot-spot analysis showed that especially electrolysis operation has a large impact on total emissions. The final Monte-Carlo simulation shows that the technology is likely to achieve a low GWP with a median of 104.0 kg CO2-eq / MWh CH4. Y1 - 2023 U6 - https://doi.org/10.2139/ssrn.4635066 PB - SSRN ER - TY - JOUR A1 - Pozzobon, Enrico A1 - Weiß, Nils A1 - Mottok, Jürgen A1 - Matoušek, Václav T1 - An evolutionary fault injection settings search algorithm for attacks on safe and secure embedded systems JF - Neural Network World (NNW) Y1 - 2023 U6 - https://doi.org/10.14311/NNW.2023.33.020 VL - 33 IS - 5 SP - 357 EP - 374 PB - Czech Technical University in Prague ER - TY - RPRT A1 - Sörgel, Dominika A1 - Luderer, Gunnar A1 - Emelianova, Polina A1 - Koch, Otto A1 - Timpe, Christof A1 - Bauer, Franz A1 - Sterner, Michael T1 - Kopernikus-Szenarienvergleich - Robuste Eigenschaften von Klimaschutzpfaden zur Treibhausgasneutralität 2045 und relevante Unsicherheiten N2 - Im Rahmen der vier Kopernikus-Projekte – Ariadne, ENSURE, P2X und SynErgie – wird die Transformation des deutschen Energiesystems hin zur Klimaneutralität analysiert. Im vorliegenden Bericht werden hierbei robuste Kernaussagen und relevante Unsicherheiten derjenigen Szenarien der Kopernikus-Schwesterprojekte dargestellt, die zur Zielsetzung die Klimaneutralität 2045 haben. Hierbei liegt der Fokus auf Indikatoren, die eine besonders hohe klimapolitische Relevanz haben. Y1 - 2023 UR - https://publications.pik-potsdam.de/pubman/faces/ViewItemFullPage.jsp?itemId=item_29216 PB - Kopernikus-Projekte CY - Potsdam ER - TY - CHAP A1 - Fuhrmann, Thomas A1 - Niemetz, Michael T1 - Analysis and Improvement of Engineering Exams Toward Competence Orientation by Using an AI Chatbot T2 - Towards a Hybrid, Flexible and Socially Engaged Higher Education: Proceedings of the 26th International Conference on Interactive Collaborative Learning (ICL2023), Volume 1 N2 - ChatGPT is currently one of the most advanced general chatbots. This development leads to diverse challenges in higher education, like new forms of teaching and learning, additional exam methods, new possibilities for plagiarism, and many more topics. On the other side with the development of advanced AI tools, pure knowledge will be less and less important, and demands from industry will change toward graduates with higher competencies. Education has therefore to be changed from knowledge-centered toward competence centered. The goal of this article is to use ChatGPT for analyzing and improving the competence orientation of exams in engineering education. The authors use ChatGPT to analyze exams from different engineering subjects to evaluate the performance of this chatbot and draw conclusions about the competence orientation of the tested exams. The obtained information is used to develop ideas for increasing the competence orientation of exams. From this analysis, it is visible that ChatGPT gives good performance mainly where knowledge is tested. It has, however, much more problems with transfer questions or tasks where students need creativity or complex insights for finding new solutions. Based on this result, exams and also lectures can be optimized toward competence orientation. KW - Engineering education KW - Competence orientation KW - Exam analysis KW - AI chatbot KW - ChatGPT Y1 - 2024 SN - 9783031519789 U6 - https://doi.org/10.1007/978-3-031-51979-6_42 SN - 2367-3370 SP - 403 EP - 411 PB - Springer Nature CY - Cham ER - TY - CHAP A1 - Fuhrmann, Thomas T1 - Let the students publish T2 - IEEE International Conference on Teaching, Assessment and Learning for Engineering (TALE), 26-29 August 2013, Bali Dynasty Resort, Kuta, Indonesia N2 - In technical study programs on the bachelor level the focus is mainly directed on the scientific education in theory and practice. Publication is usually started during the PhD phase when students write their first scientific papers. During the last years some very successful projects were made at the university of applied sciences Regensburg to motivate bachelor students doing their first own small publications. The results of these projects are presented in this paper and ideas how students can publish are given. KW - Education KW - Engineering education KW - Educational technology KW - Student project Y1 - 2013 SN - 978-1-4673-6355-6 U6 - https://doi.org/10.1109/TALE.2013.6654515 PB - IEEE ER - TY - CHAP A1 - Niemetz, Michael A1 - Fuhrmann, Thomas T1 - Wie können wir Professorinnen und Professoren ein überfachliches Studium vermitteln? T2 - Tagungsband zum 3. Symposium zur Hochschullehre in den MINT-Fächern (MINT-Symposium), Nürnberg 25. und 26.09.2017 N2 - Die Transdisziplinarität ist als wichtiger Innovationsmotor in aller Munde, entstehen doch an den Schnittstellen und in den Zwischenräumen der etablierten Wissenschaften neue Ideen und damit die zukünftige Wertschöpfung unserer Industrie. Wir alle wurden in der Welt von gestern sozialisiert, für die meisten Tätigkeiten in der Industrie war tiefes und spezialisiertes Fachwissen essentiell und auch ausreichend. Wir wurden zu Spezialisten ausgebildet und aufgrund dieser Kompetenz in der Arbeitswelt geschätzt und auch auf unsere Professuren berufen. Doch ist dies eine ausreichende Basis, um unsere Absolventinnen und Absolventen auf die neue komplexe Welt ubiquitär verfügbaren und durchsuchbaren Wissens adäquat vorzubereiten? Können wir mit unserem Mindset aus der Vergangenheit die benötigten überfachlichen Kompetenzen für die Zukunft vermitteln? Diese selbstkritische Auseinandersetzung ist schmerzhaft, doch nur durch diese Analyse können wir unsere alten Denkmuster in engen Fachdisziplinen ablegen und zu einem neuen vernetzten Denken für eine zukunftsgerichtete Lehre kommen. Y1 - 2017 UR - https://www.researchgate.net/publication/323119092_Wie_konnen_wir_Professorinnen_und_Professoren_ein_uberfachliches_Studium_vermitteln UR - https://didaktikzentrum.de/images/cwattachments/381_c76aeb3b834947e657aef252c88f6e62.pdf ER - TY - CHAP A1 - Fuhrmann, Thomas A1 - Niemetz, Michael T1 - Transdisciplinary Bachelor Course Connecting Business and Electrical Engineering T2 - 4th International Conference on Higher Education Advances (HEAd'18), 2018, Universitat Politècnica de València, València N2 - The OTH Regensburg has a broad variety of study programs in technical, business, social and health sciences. Up to now there is no integral connection in the bachelor curricula between business and technical faculties except for some small subjects. The scope of this project is to develop a new course specialization which connects engineering and business thinking. Electrical engineering students should learn basics of business science and how managers think. Business students should vice versa learn fundamentals of engineering and how engineers solve problems. Students from both faculties work together in projects where they act like start-up companies developing a new product and bringing it into the market. It is seen a transdisciplinary effect: These projects gain innovative results between the disciplines compared to student projects of one isolated discipline. Evaluation results from the first two cohorts indicate high student satisfaction, high learning success as well as directions for further improvement. KW - Business Education KW - Engineering Education KW - Project Based Learning KW - Transdisciplinary Education Y1 - 2018 U6 - https://doi.org/10.4995/HEAd18.2018.8056 ER - TY - JOUR A1 - Steinkirchner, Alfons A1 - Fuhrmann, Thomas A1 - Niemetz, Michael T1 - Channel Coded Processor for Enhanced Safety JF - International Journal of Future Computer and Communication (IJFCC) N2 - Several concepts are known for improving processor safety, all of them having their pros and cons. Some are very resource intensive, others have limited capabilities regarding the provided error safety. In this paper we use research on channel coding of noisy communication channels known from communication theory as an analogy to random bit errors in processors. We incorporate this knowledge into processor design to suggest a new error correction concept by using channel coding in processors. The new concept of a Channel Coded Processor could provide effective implementation of redundancy by the channel coding that enables error correction. The concept could also create a complete chain of redundancy in all areas and components of the processor ranging from the code compiler through the processing hardware to the output of the information. KW - Channel coded processor concept KW - communication theory KW - safety KW - soft error Y1 - 2017 U6 - https://doi.org/10.18178/ijfcc.2017.6.2.489 SN - 2010-3751 VL - 6 IS - 2 SP - 58 EP - 62 PB - International Association of Computer Science and Information CY - Singapore ER - TY - CHAP A1 - Westner, Markus A1 - Fuhrmann, Thomas A1 - Waas, Thomas A1 - Skelton, David T1 - Internationalization of a Computer Science Faculty BT - Lessons learned from a regional german technical university of applied sciences T2 - 9th Annual International Conference on Computer Science Education: Innovation and Technology (CSEIT 2018), 2018, Singapore N2 - The paper at hand describes how a regional university of applied sciences tried to internationalize its learning and teaching environment. It describes the challenges encountered, the managerial approach taken, illustrates the implemented initiatives, and how effective they turned out. The results might be relevant to faculty staff in managerial positions at regional universities all over the world that face the challenge to internationalize their teaching and learning environment for the benefit of their domestic students. KW - Internationalization KW - Faculty development KW - Change management KW - PDCA KW - Internationalisierung KW - Hochschule für angewandte Wissenschaften KW - Lernumwelt Y1 - 2018 U6 - https://doi.org/10.5176/2251-2195_CSEIT18.118 SP - 33 EP - 38 ER - TY - CHAP A1 - Cantalloube, Faustine A1 - Gomez-Gonzalez, Carlos A1 - Absil, Olivier A1 - Cantero, Carles A1 - Bacher, Regis A1 - Bonse, Markus A1 - Bottom, Michael A1 - Dahlqvist, Carl-Henrik A1 - Desgrange, Célia A1 - Flasseur, Olivier A1 - Fuhrmann, Thomas A1 - Henning, Thomas H. A1 - Jensen-Clem, Rebecca A1 - Kenworthy, Matthew A1 - Mawet, Dimitri A1 - Mesa, Dino A1 - Meshkat, Tiffany A1 - Mouillet, David A1 - Müller, André A1 - Nasedkin, Evert A1 - Pairet, Benoit A1 - Piérard, Sébastien A1 - Ruffio, Jean-Baptiste A1 - Samland, Matthias A1 - Stone, Jordan A1 - van Droogenbroeck, Marc ED - Schmidt, Dirk ED - Schreiber, Laura ED - Vernet, Elise T1 - Exoplanet imaging data challenge: benchmarking the various image processing methods for exoplanet detection T2 - Adaptive Optics Systems VII : 14-22 December 2020, online only, United States N2 - The Exoplanet Imaging Data Challenge is a community-wide effort meant to offer a platform for a fair and common comparison of image processing methods designed for exoplanet direct detection. For this purpose, it gathers on a dedicated repository (Zenodo), data from several high-contrast ground-based instruments worldwide in which we injected synthetic planetary signals. The data challenge is hosted on the CodaLab competition platform, where participants can upload their results. The specifications of the data challenge are published on our website https://exoplanet-imaging-challenge.github.io/. The first phase, launched on the 1st of September 2019 and closed on the 1st of October 2020, consisted in detecting point sources in two types of common data-set in the field of high-contrast imaging: data taken in pupil-tracking mode at one wavelength (subchallenge 1, also referred to as ADI) and multispectral data taken in pupil-tracking mode (subchallenge 2, also referred to as ADI+mSDI). In this paper, we describe the approach, organisational lessons-learnt and current limitations of the data challenge, as well as preliminary results of the participants’ submissions for this first phase. In the future, we plan to provide permanent access to the standard library of data sets and metrics, in order to guide the validation and support the publications of innovative image processing algorithms dedicated to high-contrast imaging of planetary systems. Y1 - 2020 SN - 9781510636835 U6 - https://doi.org/10.1117/12.2574803 PB - SPIE ER - TY - CHAP A1 - Fuhrmann, Thomas A1 - Niemetz, Michael T1 - Planned Chaos in Electrical Engineering Education T2 - 6th International Conference on Higher Education Advances (HEAd'20): 02.06.2020 - 05.06.2020, Valencia N2 - This paper presents the idea to intentionally introduce planned chaos into electrical engineering lectures and lab courses to improve students’ learning success. The reason to present this idea are several personal experiences in daily teaching. If students experience some uncertainty in their study program, it is seen that they have higher challenges and therefore higher learning success in managing uncertain situations. In these ways, students acquire methodical and social competences to deal with uncertainty and achieve productive results in an unstable working environment. If, however, the chaos is too large, students are over-strained with the situation, distracted from the actual learning targets and consequently learning results will be worse, drop-out rates will increase and they will be frustrated. The beneficial level of uncertainty depends on the student culture, academic progress and personality characteristics. The competence to deal with complex situations is essential for later professional life where unexpected circumstances occur regularly. Introducing planned chaos into lectures and lab courses has not to be confused with a missing didactic concept and is no justification for a bad preparation. Planned chaos is a demanding concept for professors to find the right implementation for an optimized learning outcome. These described findings are experienced from practical work and student evaluations. KW - Active Learning KW - Electrical engineering education KW - Planned Chaos Y1 - 2020 SN - 9788490488119 U6 - https://doi.org/10.4995/head20.2020.10989 PB - Universitat Politècnica de València ER - TY - CHAP A1 - Fuhrmann, Thomas A1 - Farmbauer, Michael A1 - Niemetz, Michael T1 - Integrating GNU Radio into a Virtual Course about Communication Systems T2 - 44th International Convention on Information, Communication and Electronic Technology (MIPRO): 27.09. - 01.10.2021, Opatija, Croatia N2 - Due to the COVID-19 pandemic, the course Communication Systems was transferred from presence to a virtual lecture. No hands-on lab experiments were possible. Therefore, a GNU Radio practical part was integrated into the lecture. A tutorial was written to guide students through the first steps with GNU Radio to decrease initial problems and increase student motivation. Several examples were given regarding digital signal processing, analogue and digital modulation and demodulation. Software Defined Radio receivers were set up in the amateur radio lab of the university and connected to the internet so that students were able to get real radio data to be analyzed and demodulated with their own GNU Radio models. This enables a knowledge transfer from simulated signal processing to the analysis and demodulation of real live signals. Students showed medium to high interest in practical examples during the lectures and tried their own GNU Radio simulations. Overall, the integration of GNU Radio and Software Defined Radio receivers into this virtual lecture gave additional benefits for the students to deal with signal processing and demodulation experiments. It is planned to use GNU Radio in the future for complementary practical examples to the hands-on experiments in the lab. KW - Communication engineering education KW - Communication systems KW - Data models KW - Digital modulation KW - Digital signal processing KW - GNU Radio KW - Pandemics KW - radio communication KW - Receivers KW - Software Defined Radio Y1 - 2021 SN - 978-953-233-101-1 U6 - https://doi.org/10.23919/MIPRO52101.2021.9596700 SP - 1565 EP - 1570 PB - IEEE ER - TY - CHAP A1 - Niemetz, Michael A1 - Fuhrmann, Thomas A1 - Farmbauer, Michael T1 - Comprehensive Amateur Radio Education including Public Outreach T2 - IEEE Integrated STEM Education Conference (ISEC), 16-16 March 2019, Princeton, NJ, USA N2 - An amateur radio lecture was developed and is conducted within the general education program of the Ostbayerische Technische Hochschule Regensburg. This course enables the students to participate in a variety of activities within the university. Different learning formats for communication engineering are carried out in combination with an amateur radio station of the university. Additionally, some of the projects serve as anchor points for increased visibility of the university in local society, e.g. by carrying out public events in connection with the local amateur radio community. It is seen that this course together with the amateur radio station have several positive effects for technical education and university visibility. KW - Amateur Radio KW - Antennas KW - Communication engineering education KW - Conferences KW - Education KW - Education Outreach KW - Licenses KW - PROPAGATION KW - radio communication KW - STEM Education Program Y1 - 2019 U6 - https://doi.org/10.1109/ISECon.2019.8882078 SP - 98 EP - 103 PB - IEEE ER - TY - CHAP A1 - Fuhrmann, Thomas T1 - Experiences from Transforming a Lecture “Communication Systems” from Presence to Virtual Format during the COVID-19 Pandemic T2 - 7th International Conference on Higher Education Advances (HEAd'21): 22.06.2021 - 23.06.2021, Valencia N2 - This article describes the transitions of an existing lecture “Communication Systems” from a conventional presence format to a virtual format due to the COVID-19 pandemic. The process of transformation, the evolution of the lecture during the virtual semester and the lessons learned are characterized. The changed exam format from presence to virtual format with the experiences are described. Results of a student evaluation at the end of the semester are shown. KW - communication engineering KW - Computer aided instruction KW - Electrical engineering KW - Electronic learning KW - Engineering Education KW - STEM Y1 - 2021 U6 - https://doi.org/10.4995/head21.2021.12430 SP - 297 EP - 305 PB - Universitat Politècnica de València CY - Valencia ER - TY - JOUR A1 - Westner, Markus A1 - Fuhrmann, Thomas T1 - Internationale Gastdozierende virtuell und vor Ort JF - Die Neue Hochschule Y1 - 2017 UR - https://www.hlb.de/fileadmin/hlb-global/downloads/dnh/full/2017/DNH_2017-6.pdf SP - 6 PB - hlb Hochschullehrerbund e.V. ER - TY - CHAP A1 - Fuhrmann, Thomas A1 - Niemetz, Michael T1 - Ideas on Digitally Supported Individualization of Teaching and Learning for Evolving Competency Requirements T2 - Ninth International Conference on Higher Education Advances (HEAd 23), València, June 19, 2023 – June 22, 2023 N2 - The world is changing rapidly, mainly due to the digitalization of all areas of living. A huge amount of information is accessible via the Internet, and since it is no longer possible for individual humans to keep track of it, artificial intelligence (AI) is analyzing this data. In this rapidly changing world, students have to be educated for a successful career during their whole working life. These boundary conditions lead to completely new challenges for the education of students that are unprecedented in this form. Digitalization in education can help to cope with these challenges but can only be a means, not a goal. Personal interaction with students remains the most important task in education to address individual weaknesses and further develop strengths and talents. With the increasing amount of openly available information and the consequently increasing diversity of experiences within the group of students, differentiation is advancing to become the key to successful education. Digitization can help with this challenging task and support communication between students and their experienced instructors. But computers cannot replace human interaction and attempts to improve teaching efficiency by replacing this communication with electronic means endangers the learning success for complex concepts. This article analyzes education demands and possibilities for digitally supported teaching and learning. KW - Digitalization KW - higher education KW - student competencies KW - differentiation Y1 - 2023 U6 - https://doi.org/10.4995/HEAd23.2023.16232 SN - 2603-5871 SP - 1399 EP - 1406 PB - Universitat Polit`ecnica de Val`encia ER - TY - CHAP A1 - Diehl, Andreas A1 - Wolff, Lilli A1 - Fuhrmann, Thomas A1 - Niemetz, Michael A1 - Mörtlbauer, Stefanie A1 - Dirnberger, Sandra T1 - Compact Freshmen Welcome Seminar for Engineering Students T2 - Procedia - Social and Behavioral Sciences N2 - The Faculty of Electrical Engineering and Information Technology of the OTH Regensburg developed and implemented a compact freshmen seminar for the afternoon of the first day of study. The intention of this seminar is to help the freshmen during their transition between school and study without losing lecture time in the first semester. The concept was tested with one small study group at the beginning of the summer semester 2015. To rate the impact of the seminar and to find aspects for continuous improvement an evaluation method was developed and used. Due to the good student resonance during the first run, this introduction seminar was held again in the winter semester 2015/16. It is planned to integrate this seminar as a regular session for all freshmen of the faculty curriculum and monitor the long-term effects of student motivation and success. KW - Engineering Education KW - Freshmen Seminar Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-31034 N1 - Corresponding author: Thomas Fuhrmann IS - 228 SP - 45 EP - 52 PB - Elsevier ER - TY - GEN A1 - Hipp, Susanne T1 - Small antennas in huge environments - simulation using hybrid methods T2 - Workshop des ITG-Fachausschuss HF1: Innovative Beamforming Antennas Y1 - 2022 ER - TY - CHAP A1 - Schweiberer, Philipp A1 - Rauch, Johannes A1 - Brückl, Oliver T1 - Control strategy for industrial reactive power sources depending on a specified reactive power setpoint value T2 - ETG Kongress 2023: Die Energiewende beschleunigen, 25.-26. Mai 2023, Kassel, Germany N2 - Industrial plants can provide reactive power (Q) for system- and grid-serving behavior, for which a functioning reactive power management system is essential. To make reactive power retrieval as efficient and safe as possible, the selection of reactive power sources to meet the Q-demand must consider their sensitivities and the restrictions of the industrial grid, such as operating equipment utilization or voltage limits. On this basis, a concept for a sensitivity-based control strategy that manages the reactive power retrieval of multiple reactive power sources depending on a predefined reactive power demand value is proposed. Based on the simulation of an industrial plant in the medium-voltage grid, which can provide reactive power in the form of industrial compensation systems (ICS) and generators, the operation of the algorithm is shown. Y1 - 2023 UR - https://ieeexplore.ieee.org/document/10173014/authors#authors SN - 978-3-8007-6108-1 SP - 553 EP - 558 PB - VDE VERLAG CY - Berlin ER - TY - CHAP A1 - Fuhrmann, Thomas T1 - Motivation Centered Learning T2 - 2018 IEEE Frontiers in Education Conference (FIE), 3-6 Oct. 2018, San Jose, CA, USA N2 - This Research Work in Progress Paper evaluates students’ motivation sources and shows the high impact that work of professors has on students’ motivation. Common goal of most professors is to help students acquiring knowledge and competencies that are relevant for their further life. From the beginning of Universities’ history, lectures are usually chosen to reach this goal but it is seen in recent years that they are in many cases not the optimal choice. In the last years, many efforts were made to increase students knowledge gain. From learning and motivation psychology research, many details are known how humans remember and transfer knowledge. These research results are used to create new lecture formats to activate students. Research based learning, project based lab courses, problem based learning, feedback systems, flipped classroom, blended learning and gamification in lectures are only some examples for new formats. Common goal of all these new types of learning formats is to increasing students’ motivation and to enhance learning success. In this paper, evaluations using a questionnaire with open questions were done among first year students, bachelor students before graduation and alumni, about their sources of motivation and demotivation. Interesting curricula and lectures with application related topics and possibilities for own work are the main sources of motivation. Enthusiastic professors with high competences and good lecture didactics also contribute to students’ motivation. On the other side, demotivated professors with boring lectures play a much higher role for demotivating students. Therefore, it is necessary to integrate aspects of student motivation into curriculum and lecture design and professors should become aware that they are important role-models for motivating or demotivating students. KW - Computational modeling KW - Electrical engineering KW - Information technology KW - Psychology KW - Social networking (online) KW - Task analysis KW - Urban areas Y1 - 2018 U6 - https://doi.org/10.1109/FIE.2018.8658436 SP - 1 EP - 5 PB - IEEE ER - TY - JOUR A1 - Fuhrmann, Thomas T1 - Spherical lens aberration minimization method for short-range free-space light transmission JF - Optical Engineering N2 - Spherical aberrations of lenses lead to increased spot radii on the focal plane. Several methods, such as optimizing thickness and radii or building lens groups, are known to minimize these spherical aberrations. Here, an innovative method for spherical aberration minimization is introduced; it can be used for short-range free-space optical communication systems, such as unit power afocal relay trains, lens waveguides, and periodic lens systems. This spherical aberration compensation principle is based on the combination of two identical spherical convex lenses at an optimal distance. Due to the higher refractive power for rays with an larger axis distance, rays from the outer area of the first lens intersect the inner area of the second lens, and vice versa. With this setup, the radial refractive power deviation of the two lenses compensate each other. Analytic calculations and numerical simulations are done to confirm this behavior, and measurements using two symmetric spherical lenses with polymer optical fibers as light feed confirm the calculations. Simulations and measurements show a very good matching behavior except for an unknown systematic error. At a lens distance of 300 mm, the optical attenuation decreased by ∼2 dB compared with a very small lens distance. This leads to the conclusion that this proposed spherical aberration minimization method works as theoretically predicted. KW - Monochromatic aberrations KW - Signal attenuation KW - Spherical lenses KW - Polymer optical fibers KW - Monte Carlo methods KW - Free space optics KW - Optical testing KW - Distance measurement KW - Optical engineering KW - Optical simulations Y1 - 2022 U6 - https://doi.org/10.1117/1.OE.61.8.085101 SN - 1560-2303 SN - 0036-1860 SN - 0091-3286 VL - 61 IS - 8 PB - SPIE CY - Bellingham, Wash. ER - TY - CHAP A1 - Wick, Michael A1 - Lindner, Gerhard A1 - Zimmer, Katja A1 - Schreiner, Rupert A1 - Fuhrmann, Thomas A1 - Seebauer, Gudrun A1 - Xu, Boqing A1 - Zheng, Jihong A1 - Wang, Ning ED - Liu, Xu ED - Zhang, Xi-Cheng T1 - German-Chinese cooperative Bachelor in engineering physics/optoelectronics T2 - 14th Conference on Education and Training in Optics and Photonics: ETOP 2017; Hangzhou, China 29.05.2017 - 31.05.2017 N2 - The University of Shanghai for Science and Technology (USST), the Coburg University of Applied Sciences and Arts (CUASA) and the OTH Regensburg, University of Applied Sciences (OTHR) established an English taught international cooperative bachelor program in the area of Engineering Physics/Optoelectronics. Students from China study their first four semesters at USST. They continue their studies in Germany for the last three semesters, including an internship and a bachelor thesis, graduating with a Chinese and a German bachelor degree. Students from Germany study their third and fourth semester at USST to gain international experience. While the first cohort of Chinese students is currently in Germany, the second cohort of German students is in Shanghai. Up to now the feedback regarding this study program is completely positive, thus it is planned to develop it further. Y1 - 2017 SN - 9781510613812 U6 - https://doi.org/10.1117/12.2269943 PB - SPIE ER - TY - CHAP A1 - Zheng, Jihong A1 - Fuhrmann, Thomas A1 - Xu, Boqing A1 - Schreiner, Rupert A1 - Jia, Hongzhi A1 - Zhang, Wei A1 - Wang, Ning A1 - Seebauer, Gudrun A1 - Zhu, Jiyan T1 - Curriculum design and German student exchange for Sino-German Bachelor program majored in optoelectronics engineering T2 - 14th Conference on Education and Training in Optics and Photonics (ETOP 2017), 29-31.05.2017, Hangzhou, China, 29-31.05.2017 N2 - Different higher education backgrounds in China and Germany led to challenges in the curriculum design at the beginning of our cooperative bachelor program in Optoelectronics Engineering. We see challenges in different subject requirements from both sides and in the German language requirements for Chinese students. The curriculum was optimized according to the AS IIN criteria, which makes it acceptable and und erstandable by both countries. German students are integrated into the Chinese class and get the sa me lectures like their Chinese colleagues. Intercultural and curriculum challenges are successfully solved. The results are summarized to provide an example for other similar international programs. KW - cooperative bachelor program KW - optoelectronics KW - microsystems KW - student exchange Y1 - 2017 U6 - https://doi.org/10.1117/12.2269574 PB - SPIE ER - TY - CHAP A1 - Blank, M. A1 - Brunner, Stefan A1 - Fuhrmann, Thomas A1 - Meier, Hans A1 - Niemetz, Michael T1 - Embedded Linux in engineering education T2 - 2015 IEEE Global Engineering Education Conference (EDUCON), 18-20 March 2015, Tallinn, Estonia N2 - With the availability of cost effective embedded Linux solutions and the increasing complexity of embedded devices because of growing calculation power and communication demand, Linux is getting increasingly interesting as an operating system for the design of embedded control solutions. This is the case for almost all technical applications in electrical engineering like energy distribution systems, high level communication, signal processing or industrial automation. In the engineering master courses at the OTH Regensburg, a lecture is offered introducing students to Linux with a strong focus on embedded applications. This paper describes the concept of the lecture including the laboratory set up and gives some examples of embedded Linux projects performed by students. KW - Engineering Education KW - Linux KW - Operating systems KW - Ports (Computers) KW - Universal Serial Bus KW - Vehicles KW - Wireless communication Y1 - 2015 U6 - https://doi.org/10.1109/EDUCON.2015.7095964 SP - 145 EP - 150 PB - IEEE ER - TY - CHAP A1 - Fuhrmann, Thomas T1 - Realizing a complex student project over several semesters T2 - Proceedings of the 2012 IEEE Global Engineering Education Conference (EDUCON), 17-20 April 2012, Marrakech, Morocco N2 - Project Based Learning (PBL) has become a popular method for lab courses to teach practical topics. Most of the student projects are tailored in their complexity and need a defined time for a student team within one semester. With this defined and often reduced complexity of the projects the practical relevance is doubtful. In this here shown approach for a PBL lab an industry project with the original complexity is used and structured into several parts. These are sequentially dependent and have to be solved in a defined order by student groups. Each group has to develop one component and has the responsibility for a working result at the end of their subproject. Each group interacts with other groups during the same semester to develop a working system. Student groups in the following semesters take the results from previous semesters and develop the entire project further on. With this type of PBL an own dynamic of the student work is evolving which is not possible with small complexity tailored projects. Y1 - 2012 SN - 978-1-4673-1456-5 SN - 978-1-4673-1457-2 SN - 978-1-4673-1455-8 U6 - https://doi.org/10.1109/EDUCON.2012.6201067 SN - 2165-9567 SN - 2165-9559 PB - IEEE ER - TY - GEN ED - Mottok, Jürgen ED - Ehrlich, Ingo ED - Haumer, Anton T1 - Regensburger Applied Research Conference 2020 (RARC 2020), July 31st BT - Proceedings N2 - The Applied Research Conference which is held every year at another University of Applied Sciences in Bavaria is the main event for all students in the Master of Applied Research program. They come together to present their work in oral presentations and full papers, which are published in the proceedings, as well as poster presentations of the students after their 1st semester. For sure it is interesting for Professors and interested people to see the results of upcoming scientists and researchers. Due to the Corona pandemic, this year it is not possible to organize the conference as usual in presence. We have to refrain from face-to-face discussions, having together a cup of coffee. We as Professors at the OTH Regensburg wanted to give our students the chance to finish this semester successfully – despite all limitations due to the pandemic situation. Therefore we decided to organize the RARC 2020 – Regensburg Applied Research Conference 2020 – for the Master of Applied Research students of OTH Regensburg as an online conference. However, for a Technical University the situation is rather a challenge than a problem. Using a variety of online tools for teaching during this semester, we have enough experience to find a setup for RARC2020. We received 28 submissions for full papers, which were peer reviewed and 26 of them were accepted – you will find them in this proceedings, and they will be presented orally on July 31st, 2020. Additionally, there are 22 posters which will be presented on the same day. During the Plenary Opening Session, after a welcome by our President Prof. Dr. Wolfgang Baier we will have 3 Keynote speakers: Prof. Dr. phil. habil. Karsten Weber: Erkenntnistheorie für Ingenieure Prof. em. Georg Scharfenberg: 11 Years Master of Applied Research Alumnis Veronika Fetzer: Entrepreneurship KW - Applied Research Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-6417 CY - Regensburg ER - TY - CHAP A1 - Kraus, Hermann A1 - Brückl, Oliver T1 - Automated use of wired measures in grid planning for solving current and voltage band problems T2 - Power and Energy Student Summit (PESS) 2019, Magdeburg N2 - This work deals with the use of cable exchange and parallel cabling as network expansion measures in the context of an automated grid planning for the elimination of current and voltage band problems in a distribution network. Inter alia, reference is made to a higher-level program, which is being developed in the EU project "CrossEnergy", and the procedures for remedying the limit value violations are presented. KW - Netzplanung KW - Automatisierung KW - Netzverstärkung KW - Leitungsmaßnahme Y1 - 2019 SN - 978-3-944722-84-9 U6 - https://doi.org/10.24352/UB.OVGU-2019-086 VL - 77 SP - 207 EP - 211 PB - Otto-von-Guericke-Universität, Institut für Elektrische Energiesysteme CY - Magdeburg ER - TY - JOUR A1 - Kriegl, Raphael A1 - Jezeršek, Matija A1 - Kravanja, Gaia A1 - Hribar, Luka A1 - Mukhi, Soham A1 - Kokot, Gašper A1 - Drevenšek-Olenik, Irena A1 - Shamonin, Mikhail T1 - Tunable rebound of millimeter-sized rigid balls by magnetic actuation of elastomer-based surface microstructures JF - Smart Materials and Structures N2 - A novel method for controlling the rebound behavior of small balls made of Al2O3 with a radius of 2.381 mm is presented. It uses different types of micro-structured surfaces of soft magnetoactive elastomers. These surfaces were fabricated via laser micromachining and include fully ablated surfaces as well as micrometer-sized lamellas with a fixed width of 90 µm, height of 250 µm and three different gap sizes (15, 60 and 105 µm). The lamellas can change their orientation from edge-on to face-on configuration according to the direction of the external magnetic field from a permanent magnet. The orientation of the external magnetic field significantly influences the rebound behavior of the balls, from a coefficient of restitution e of to < 0.1. The highest relative change in the coefficient of restitution between zero field and face-on configuration of is observed for lamellas with a gap of 60 µm. Other characteristics of the ball rebound such as the penetration depth into an Magnetoactive elastomer and the maximum deceleration are investigated as well. The proposed method does not require a constant power supply due to the use of permanent magnets. It may find novel applications in the field of impact engineering. Y1 - 2024 U6 - https://doi.org/10.1088/1361-665X/ad41a9 VL - 33 IS - 6 PB - IOP Science ER - TY - JOUR A1 - Marterer, Verena A1 - Radouchová, Michaela A1 - Soukup, Radek A1 - Hipp, Susanne A1 - Blecha, Tomáš T1 - Wearable textile antennas: investigation on material variants, fabrication methods, design and application JF - Fashion and Textiles N2 - With the ongoing miniaturization of wireless devices, the importance of wearable textiles in the antenna segment has increased significantly in recent years. Due to the widespread utilization of wireless body sensor networks for healthcare and ubiquitous applications, the design of wearable antennas offers the possibility of comprehensive monitoring, communication, and energy harvesting and storage. This article reviews a number of properties and benefits to realize comprehensive background information and application ideas for the development of lightweight, compact and low-cost wearable patch antennas. Furthermore, problems and challenges that arise are addressed. Since both electromagnetic and mechanical specifications must be fulfilled, textile and flexible antennas require an appropriate trade-off between materials, antenna topologies, and fabrication methods—depending on the intended application and environmental factors. This overview covers each of the above issues, highlighting research to date while correlating antenna topology, feeding techniques, textile materials, and contacting options for the defined application of wearable planar patch antennas. KW - Wearable communication KW - Textile antenna KW - Patch antenna KW - Design requirements KW - Smart textiles KW - E-textiles Y1 - 2024 U6 - https://doi.org/10.1186/s40691-023-00369-1 VL - 11 PB - Springer Open ER - TY - INPR A1 - Schumm, Leon A1 - Abdel-Khalek, Hazem A1 - Brown, Tom A1 - Ueckerdt, Falko A1 - Sterner, Michael A1 - Fioriti, Davide A1 - Parzen, Max T1 - The impact of temporal hydrogen regulation on hydrogen exporters and their domestic energy transition N2 - As global demand for green hydrogen rises, potential hydrogen exporters move into the spotlight. However, the large-scale installation of on-grid hydrogen electrolysis for export can have profound impacts on domestic energy prices and energy-related emissions. Our investigation explores the interplay of hydrogen exports, domestic energy transition and temporal hydrogen regulation, employing a sector-coupled energy model in Morocco. We find substantial co-benets of domestic climate change mitigation and hydrogen exports, whereby exports can reduce domestic electricity prices while mitigation reduces hydrogen export prices. However, increasing hydrogen exports quickly in a system that is still dominated by fossil fuels can substantially raise domestic electricity prices, if green hydrogen production is not regulated. Surprisingly, temporal matching of hydrogen production lowers domestic electricity cost by up to 31% while the effect on exporters is minimal. This policy instrument can steer the welfare (re-)distribution between hydrogen exporting firms, hydrogen importers, and domestic electricity consumers and hereby increases acceptance among actors. KW - Energy Transition KW - Hydrogen regulation KW - Hydrogen export KW - Climate-neutral KW - Domestic prices KW - Hydrogen prices KW - Power-to-X Y1 - 2024 U6 - https://doi.org/10.21203/rs.3.rs-4285425/v1 PB - Research Square Platform LLC ER - TY - CHAP A1 - Haumer, Anton T1 - Modeling and Control Design of an Educational Magnetic Levitation System T2 - Proceedings of the 15th International Modelica Conference 2023, Aachen, October 9-11 N2 - A magnetic levitation system is a perfect educational example of a nonlinear unstable system. Only with suitable control, a small permanent magnet can be held floating stable below a coil. After modeling and simulation of the system, control of the system can be developed. At the end, the control algorithm can be coded on a microcontroller, connected to a pilot plant. KW - mechatronics KW - magnetic levitation KW - time-discrete control KW - functional mockup interface Y1 - 2023 U6 - https://doi.org/10.3384/ecp204763 SN - 1650-3686 PB - Linköping University Electronic Press ER - TY - JOUR A1 - Loo, Xuyan A1 - Nagaraju, Bhavana A1 - Pathivada, Sai A1 - Bartsch, Alexander A1 - Schratzenstaller, Thomas A1 - Sattler, Robert A1 - Monkman, Gareth J. T1 - Electrical properties of bisphenol-A-free magnetoactive borosilicate polymers JF - AIP Advances N2 - The recent REACH regulations require the elimination of bisphenol-A and titanium dioxide from commercially available boron-based polymers. This has led to changes in some of the mechanical characteristics, which strongly influence the properties of magnetoactive borosilicate polymers. This work delivers results on the electrical properties and discusses some implications for future research using bisphenol-A and titanium-dioxide-free substitutes. KW - Electrical components KW - Electrical properties and parameters KW - Dielectric properties KW - Electrical resistivity KW - Magnetic materials KW - Viscoelasticity KW - Polymers KW - Non Newtonian fluids KW - Magnetic fluids Y1 - 2024 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-72936 SN - 2158-3226 N1 - Corresponding author der OTH Regensburg: Gareth J. Monkman VL - 14 IS - 5 PB - AIP Publishing ER - TY - JOUR A1 - Keiner, Dominik A1 - Ram, Manish A1 - Barbosa, Larissa de Souza Noel Simas A1 - Bogdanov, Dmitrii A1 - Breyer, Christian T1 - Cost optimal self-consumption of PV prosumers with stationary batteries, heat pumps, thermal energy storage and electric vehicles across the world up to 2050 JF - Solar Energy N2 - Globally, PV prosumers account for a significant share of the total installed solar PV capacity, which is a growing trend with ever-increasing retail electricity prices. Further propelled by performance improvements of solar PV and innovations that allow for greater consumer choice, with additional benefits such as cost reductions and availability of incentives. PV prosumers may be one of the most important enablers of the energy transition. PV prosumers are set to gain the most by maximising self-consumption, while avoiding large amounts of excess electricity being fed into the grid. Additionally, electricity and heat storage technologies, heat pumps and battery electric vehicles are complementary to achieve the highest possible self-consumption shares for residential PV prosumer systems, which can reach grid-parity within this decade in most regions of the world. This research finds the cost optimal mix of the various complementary technologies such as batteries, electric vehicles, heat pumps and thermal heat storage for PV prosumers across the world by exploring 4 different scenarios. Furthermore, the research presents the threshold for economical maximum battery capacity per installed PV capacity, along with self-consumption ratios, demand cover ratios and heat cover ratios for 145 different regions across the world. This is a first of its kind study to conduct a global analysis of PV prosumers with a range of options to meet their complete energy demand from a future perspective, up to 2050. Maximising self-consumption from solar PV generation to meet all energy needs will be the most economical option in the future, for households across most regions of the world. KW - Battery KW - Electric vehicle KW - EMISSIONS KW - Heat pump KW - LIFE-CYCLE COST KW - Optimization KW - Photovoltaics KW - POWER-TO-HEAT KW - Prosumer KW - RESIDENTIAL HEAT KW - SYSTEMS KW - TECHNOLOGIES KW - Thermal energy storage KW - Vehicle-to-home Y1 - 2019 U6 - https://doi.org/10.1016/j.solener.2019.04.081 VL - 185 SP - 406 EP - 423 PB - Elsevier ER - TY - JOUR A1 - Kral, Christian A1 - Haumer, Anton A1 - Kapeller, Hansjörg A1 - Pirker, Franz T1 - Design and Thermal Simulation of Induction Machines for Traction in Electric and Hybrid Electric Vehicles JF - World Electric Vehicle Journal N2 - An electric traction machine for an electric or a hybrid electric vehicle is usually designed for a specific operating point or cycle. For such an operating point or cycle, the masses and the cooling circuit of the electric machine determine the time dependent temperature distribution within the machine. For a specific load cycle, the thermal simulation of the machine can reveal possible mass and size reductions for a given insulation class of the machine. In addition, such simulations allow the comparison of various cooling concepts. In the machine design process, the first step is a conventional electromagnetic machine design. From the geometric data of this design and the material properties, the parameters of a thermal equivalent circuit can be derived. The differential and algebraic equations of the thermal equivalent circuit are solved by a simulation tool to predict the temperatures of the critical parts in the electric machine. A thermal equivalent circuit is accurate enough to predict the thermal behavior of the critical parts in the electric machine, and yet not too complex, to obtain simulation results with moderate numerical effort. This enables an iterative design process to optimize the drive. KW - Induction Motor KW - Electric Drive KW - Modeling KW - Simulation KW - Thermal Management Y1 - 2007 U6 - https://doi.org/10.3390/wevj1010190 SN - 2032-6653 VL - 1 IS - 1 SP - 190 EP - 196 PB - MDPI ER - TY - JOUR A1 - Maier, Robert A1 - Schlattl, Andreas A1 - Guess, Thomas A1 - Mottok, Jürgen T1 - CausalOps - Towards an industrial lifecycle for causal probabilistic graphical models JF - Information and Software Technology N2 - Context: Causal probabilistic graph-based models have gained widespread utility, enabling the modeling of cause-and-effect relationships across diverse domains. With their rising adoption in new areas, such as safety analysis of complex systems, software engineering, and machine learning, the need for an integrated lifecycle framework akin to DevOps and MLOps has emerged. Currently, such a reference for organizations interested in employing causal engineering is missing. This lack of guidance hinders the incorporation and maturation of causal methods in the context of real-life applications. Objective: This work contextualizes causal model usage across different stages and stakeholders and outlines a holistic view of creating and maintaining them within the process landscape of an organization. Method: A novel lifecycle framework for causal model development and application called CausalOps is proposed. By defining key entities, dependencies, and intermediate artifacts generated during causal engineering, a consistent vocabulary and workflow model to guide organizations in adopting causal methods are established. Results: Based on the early adoption of the discussed methodology to a real-life problem within the automotive domain, an experience report underlining the practicability and challenges of the proposed approach is discussed. Conclusion: It is concluded that besides current technical advancements in various aspects of causal engineering, an overarching lifecycle framework that integrates these methods into organizational practices is missing. Although diverse skills from adjacent disciplines are widely available, guidance on how to transfer these assets into causality-driven practices still need to be addressed in the published literature. CausalOps’ aim is to set a baseline for the adoption of causal methods in practical applications within interested organizations and the causality community. KW - Causal engineering KW - Model lifecycle KW - MLOps KW - Causal graphical models Y1 - 2024 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-73350 SN - 0950-5849 N1 - Corresponding author der OTH Regensburg: Robert Maier PB - Elsevier ER - TY - GEN A1 - Marterer, Verena T1 - Simulation of the Electromagnetic Properties of Knitted Structures N2 - Designing textile Antennas is still challenging, as normal antenna design does not account for the textile nature of the materials: The e-Tex project investigates knitted and embroidered antennas to enhance the design process. The presentation shows first investigations in particular of knitted structures using measurement, simulation and theoretical models. In addition, plans to include measured models in simulation, in order to yield accurate results, will be presented. KW - Textile Antennas KW - Wearables KW - Periodic Structure Y1 - 2024 ER -