@inproceedings{HaenninenNiemetzSchoepe, author = {H{\"a}nninen, Risto and Niemetz, Michael and Schoepe, Wilfried}, title = {Transition to turbulence in oscillatory superflows}, series = {ETC 2013 - 14th European Turbulence Conference 2020: 2 September 2013 - 4 September 2013, Lyon, France}, booktitle = {ETC 2013 - 14th European Turbulence Conference 2020: 2 September 2013 - 4 September 2013, Lyon, France}, abstract = {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.}, language = {en} } @inproceedings{RiegerMuehlbauerRabletal., author = {Rieger, Anna and M{\"u}hlbauer, Christian and Rabl, Hans-Peter and Weber, Rainer}, title = {Dissonanz als Bewertungskriterium multi-tonalen Schalls}, series = {Fortschritte der Akustik - DAGA 2020: 46. Deutsche Jahrestagung f{\"u}r Akustik}, booktitle = {Fortschritte der Akustik - DAGA 2020: 46. Deutsche Jahrestagung f{\"u}r Akustik}, publisher = {Deutsche Gesellschaft f{\"u}r Akustik e.V.}, pages = {788 -- 791}, language = {de} } @inproceedings{MuehlbauerRablRottengruber, author = {M{\"u}hlbauer, Christian and Rabl, Hans-Peter and Rottengruber, Herrmann}, title = {Development of a Methodology for Acoustic Analysis and Optimization of Mechatronic Fuel Injection Systems}, series = {Automotive Acoustics Conference 2019: Proceedings, 5. Internationale ATZ-Fachtagung Fahrzeugakustik}, booktitle = {Automotive Acoustics Conference 2019: Proceedings, 5. Internationale ATZ-Fachtagung Fahrzeugakustik}, editor = {Siebenpfeiffer, Wolfgang}, publisher = {Springer Vieweg}, address = {Wiesbaden}, isbn = {978-3-658-27668-3}, doi = {10.1007/978-3-658-27669-0_15}, pages = {211 -- 225}, abstract = {To identify the sound quality of fuel injection systems as a frontloading measure, a system test bench has been developed that simulates the structure and airborne noise emission. The setup of the system test bench includes an assembly of the acoustical relevant engine parts and an encapsulated drive for the high-pressure pump. A specific control unit enables a high variability for the operation strategy of the injection system. The focus of this study is on the development of a methodology to analyze and optimize the sound quality of gasoline direct injectors in critical operation points by suitable active means. For this, the injection parameters in engine idle have been identified and subsequently transferred to the system test bench. Additionally, the injection parameters have been optimized acoustically and the impacts on the key functions regarding injection rating and shot-to-shot scattering of the injected fuel mass are discussed.}, language = {en} } @inproceedings{ReindlMeierNiemetz, author = {Reindl, Andrea and Meier, Hans and Niemetz, Michael}, title = {Scalable, Decentralized Battery Management System Based on Self-organizing Nodes}, series = {Architecture of computing systems - ARCS 2020: 33rd international conference, Aachen, Germany, May 25-28, 2020, proceedings}, volume = {12155}, booktitle = {Architecture of computing systems - ARCS 2020: 33rd international conference, Aachen, Germany, May 25-28, 2020, proceedings}, editor = {Brinkmann, Andr{\´e} and Karl, Wolfgang and Lankes, Stefan and Tomforde, Sven and Pionteck, Thilo and Trinitis, Carsten}, publisher = {Springer International Publishing}, address = {Cham}, isbn = {978-3-030-52793-8}, doi = {10.1007/978-3-030-52794-5_13}, pages = {171 -- 184}, abstract = {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.}, language = {en} } @inproceedings{AndersBriemNovaketal., author = {Anders, M. and Briem, Ulrich and Novak, G. and Steinbach, G.}, title = {Neue VDI-Richtlinie f{\"u}r die Seiltriebauslegung}, series = {28. Internationale Kranfachtagung 2020 "Kran 4.0: Potenziale der Digitalisierung", 4. und 5. M{\"a}rz 2020, Magdeburg}, booktitle = {28. Internationale Kranfachtagung 2020 "Kran 4.0: Potenziale der Digitalisierung", 4. und 5. M{\"a}rz 2020, Magdeburg}, editor = {Katterfeld, Andr{\´e} and Krause, Friedrich and Pfeiffer, Dagmar and Richter, Klaus}, publisher = {LOGiSCH GmbH}, address = {Magdeburg}, isbn = {978-3-947068-08-1}, pages = {59 -- 72}, language = {de} } @inproceedings{DiamantidisSykora, author = {Diamantidis, Dimitris and S{\´y}kora, Miroslav}, title = {Reliability Differentiation and Uniform Risk in Standards}, series = {Scientific Symposium Future Trends in Civil Engineering, Zagreb,Croatia, 17 October 2029}, booktitle = {Scientific Symposium Future Trends in Civil Engineering, Zagreb,Croatia, 17 October 2029}, doi = {10.5592/CO/FTCE.2019.11}, pages = {241 -- 260}, abstract = {Reliability of structures and infrastructures is a major issue in structural engineering. Structural standards have traditionally been mainly concerned with public safety preventing loss of life or injury; this view has been shifting in recent years towards minimisation of economic loss. This contribution discusses the reliability differentiation principle in modern standards. Its aim is to achieve uniform risk levels for the various classes of structures. Codified criteria for reliability differentiation and risk informed decisions inherent in standards and especially in the Eurocodes are critically reviewed. It is shown that the classification of structures based on consequences of failure is an approach that has not been widely implemented in everyday design. Practical rules for the classification and implementation in design are needed and related proposals are presented.}, language = {en} } @inproceedings{Roesel, author = {R{\"o}sel, Birgit}, title = {A concept of a mainly digitalized course on control theory including problembased practical units and digital supported exams}, series = {HEAd'20: Sixth International Conference on Higher Education Advances, June 2 - June 5 2020, Valencia (Spain)}, booktitle = {HEAd'20: Sixth International Conference on Higher Education Advances, June 2 - June 5 2020, Valencia (Spain)}, doi = {10.4995/HEAd20.2020.11112}, abstract = {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.}, language = {en} } @article{MalzKrenkelSteffens, author = {Malz, Sebastian and Krenkel, Walter and Steffens, Oliver}, title = {Infrared Reflective Wall Paint in Buildings: Energy Saving Potentials and Thermal Comfort}, series = {Energy and Buildings}, volume = {224}, journal = {Energy and Buildings}, number = {October}, publisher = {Elsevier}, issn = {0378-7788}, doi = {10.1016/j.enbuild.2020.110212}, abstract = {The reduction of the energy demand of existing buildings is the main objective of building refurbishment. Managing the heat radiation properties of the wall construction is a possible way to develop highly effective and resource efficient insulation materials and concepts. The application of infrared reflective wall paints and coatings has been studied since the latter half of the 20th century. A brief review of the literature gives an account of the current research status. One has to realise that the conclusions are not uniformly consistent but depend strongly on the specific boundary conditions and investigated parameters. The study presented here discusses the usage of infrared reflective wall paint in conjunction with heat insulation for historic brick masonry. The possible energy savings are linked to the resulting thermal comfort. We identify critical parameters that must be taken into account when using infrared reflective wall paint and derive recommended design rules for the refurbishment of such building types. The findings prove that infrared reflective wall paint can decrease heat losses by 18\% and up to 22\% if comfort conditions are considered. Increasing energy savings can also cause the negative effect of high radiative asymmetry. Thus, each configuration must be observed in detail.}, language = {en} } @article{SchulzSchwarz, author = {Schulz, Carsten and Schwarz, Colin}, title = {Drivetrain fatigue strength characteristics of model-predictive control for wind turbines}, series = {Wind Energy}, volume = {23}, journal = {Wind Energy}, number = {12}, publisher = {Wiley}, doi = {10.1002/we.2520}, pages = {2137 -- 2149}, abstract = {Wind turbines play a crucial role in the revolution towards renewable resources. They need to be economically competitive to be sustainable. This still requires to lower the cost of energy (COE). To this end, nonlinear model predictive control (NMPC) is used within this paper. As known from literature, NMPC significantly improves the energy extracting performance as well as the mitigation of tower loads of wind turbines. As it is shown in this paper, the drivetrain fatigue strength drops disproportionally in parallel, which either increases the demands on the turbine design or decreases the lifetime of drivetrain components. Without additional boundary conditions to the underlying optimal control problems (OCPs), the application of energy-maximizing NMPC might so even raise the COE. Only penalizing axial torque oscillations by quadratic terms decreases energy-extracting performance below the level of classical wind turbine controllers. This makes more sophisticated conditions necessary. In this paper, the increase of the drivetrain damage by NMPC is analyzed, and appropriate boundary conditions are derived, to balance the two contradicting objectives of energy maximization and drivetrain load mitigation. An NMPC approach based on indirect methods is used, to obtain a solution of the OCPs very efficiently. It applies the Hamilton equations and Pontryagin's maximum principle. Its accuracy and efficiency to solve OCPs was presented over the last decades.}, language = {en} } @inproceedings{SippenauerBrueckl, author = {Sippenauer, Thomas and Br{\"u}ckl, Oliver}, title = {Verankerung von Flexibilit{\"a}t in der Netzplanung}, series = {ScienceLab (begleitender Workshop zur Konferenz Zuk{\"u}nftige Stromnetze: 29.-30. Januar 2020, Berlin)}, booktitle = {ScienceLab (begleitender Workshop zur Konferenz Zuk{\"u}nftige Stromnetze: 29.-30. Januar 2020, Berlin)}, publisher = {Conexio GmbH}, address = {Pforzheim}, isbn = {978-3-948176-07-5}, doi = {10.35096/othr/pub-5559}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-55592}, pages = {77 -- 81}, abstract = {Im Rahmen des Projektes C/sells wurden mehrere Mittelspannungsnetze modelliert, um die aktuellen Spannungsverh{\"a}ltnisse und Leitungsauslastungen nachbilden zu k{\"o}nnen. Zudem wurden, angelehnt an den Netzentwicklungsplan, Szenarien f{\"u}r den zuk{\"u}nftigen PV-Zubau und die potenzielle Entwicklung der Elektromobilit{\"a}t entworfen. Auf Basis der Ergebnisse l{\"a}sst sich eine Netzanalyse hinsichtlich Spannungs- und Stromgrenzwert{\"u}berschreitungen sowie zu deren potenziellen Auftrittszeitpunkten und Auftrittsdauern durchf{\"u}hren. Parallel wurde anhand von Sensitivit{\"a}tsanalysen untersucht, welche Wirksamkeit Flexibilit{\"a}tseins{\"a}tze an den verschiedenen Netzknoten auf den Engpass haben. Dadurch kann bestimmt werden, wie effektiv die verf{\"u}gbaren, in der Regel {\"o}rtlich gebundenen Flexibilit{\"a}tsanbieter eingesetzt werden k{\"o}nnen. Da die Sensitivit{\"a}ten arbeitspunktabh{\"a}ngig sind, wurden verschiedene Zeitpunkte im Jahresverlauf berechnet und die jeweilige {\"A}nderungen der Wirksamkeit ausgewertet. Neben der H{\"o}he der Leistungsabweichung wurde die Flexibilit{\"a}tsanforderung auch anhand der Einsatzzeitpunkte und Einsatzdauer sowie anhand der H{\"a}ufigkeit der n{\"o}tigen Flexibilit{\"a}tseins{\"a}tze charakterisiert. Aus den gewonnenen Erkenntnissen soll abgeleitet werden, inwiefern sich der flexible Einsatz der Verbrauchsanlagen in der Netzplanung verankern l{\"a}sst. Besonders relevant ist deshalb, mit welcher Verl{\"a}sslichkeit die Flexibilit{\"a}t abgerufen werden kann. Eine sehr hohe Verl{\"a}sslichkeit l{\"a}sst sich je nach Flexibilit{\"a}tsanbieter m{\"o}glicherweise nicht oder nur zu sehr hohen Preisen gew{\"a}hrleisten. Die Eignung der Flexibilit{\"a}tseins{\"a}tze wird somit sowohl aus technischer als auch aus wirtschaftlicher Sicht bewertet. Da eine vollst{\"a}ndige Verl{\"a}sslichkeit ohnehin nicht sichergestellt werden kann (technische St{\"o}rungen einer Anlage, Wettereinfl{\"u}sse, etc.), werden auch Fallback-Strategien, z. B. Einspeisespitzenkappung, in die Analyse einbezogen.}, language = {de} } @inproceedings{SippenauerBrueckl, author = {Sippenauer, Thomas and Br{\"u}ckl, Oliver}, title = {Erschließung der Flexibilit{\"a}tspotenziale eines Trinkwasserversorgungssystems}, series = {ScienceLab (begleitender Workshop zur Konferenz „Zuk{\"u}nftige Stromnetze": 2020, Berlin)}, booktitle = {ScienceLab (begleitender Workshop zur Konferenz „Zuk{\"u}nftige Stromnetze": 2020, Berlin)}, publisher = {Conexio GmbH}, address = {Pforzheim}, isbn = {978-3-948176-07-5}, doi = {10.35096/othr/pub-5562}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-55629}, pages = {126 -- 130}, abstract = {In Zusammenarbeit mit den Kreiswerken Cham wurde an der OTH Regensburg das Trinkwasserversorgungsgebiet mit allen relevanten Pumpen und Hochbeh{\"a}ltern nachgebildet. Mithilfe des Modells kann die aktuelle, f{\"u}llstandgesteuerte Betriebsweise unter Einhaltung der Randbedingungen (Grenzwerte der Beh{\"a}lterf{\"u}llst{\"a}nde, elektrische Verschaltung der Pumpen) simuliert werden. Daraus l{\"a}sst sich auch das gesicherte, f{\"u}r die Netzplanung geeignete Flexibilit{\"a}tspotenzial anhand der Leistungsabweichung gegen{\"u}ber dem regul{\"a}ren Fahrplan, der Einsatzdauer, dem Einsatzzeitpunkt und der Pause zwischen den Flexibilit{\"a}tsabrufen charakterisieren. In einem Feldversuch wurde vordergr{\"u}ndig untersucht, inwiefern der Einsatz von Flexibilit{\"a}t in der Trinkwasserversorgung technisch umsetzbar ist.}, language = {de} } @inproceedings{KrausBrueckl, author = {Kraus, Hermann and Br{\"u}ckl, Oliver}, title = {Use and Programmatic Extension of PowerFactory for the Implementation of Automated Network Planning at the Distribution Grid Level}, series = {2020 10th International Conference on Advanced Computer Information Technologies (ACIT): 16-18 Sept. 2020}, booktitle = {2020 10th International Conference on Advanced Computer Information Technologies (ACIT): 16-18 Sept. 2020}, publisher = {IEEE}, doi = {10.1109/ACIT49673.2020.9208900}, pages = {731 -- 736}, abstract = {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.}, language = {en} } @inproceedings{HopfenspergerDaubnerHerrmannetal., author = {Hopfensperger, Bernhard and Daubner, Andreas and Herrmann, Fabian and Hopkins, Andrew and Mellor, Phil}, title = {Investigation of Shifted PWM Methods for a Dual Three-Phase System to Reduce Capacitor RMS Current}, series = {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]}, booktitle = {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]}, publisher = {VDE-Verlag}, address = {Berlin, Offenbach}, isbn = {978-3-8007-5245-4}, pages = {124 -- 131}, abstract = {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.}, subject = {Elektroantrieb}, language = {en} } @incollection{LangSteinbornSteffensetal., author = {Lang, Christian and Steinborn, Florian and Steffens, Oliver and Lang, Elmar Wolfgang}, title = {Applying a 1D-CNN Network to Electricity Load Forecasting}, series = {Theory and Applications of Time Series Analysis}, booktitle = {Theory and Applications of Time Series Analysis}, editor = {Valenzuela, O. and Rojas, F. and Herrera, L.J. and Pomares, H. and Rojas, I.}, publisher = {Springer}, doi = {10.1007/978-3-030-56219-9_14}, pages = {205 -- 218}, abstract = {This paper presents a convolutional neural network (CNN) which can be used for forecasting electricity load profiles 36 hours into the future. In contrast to well established CNN architectures, the input data is one-dimensional. A parameter scanning of network parameters is conducted in order to gain information about the influence of the kernel size, number of filters and number of nodes. Furthermore, different dropout methods are applied to the CNN and are evaluated. The results show that a good forecast quality can already be achieved with basic CNN architectures, the dropout improves the forecast. The method works not only for smooth sum loads of many hundred consumers, but also for the load of single apartment buildings.}, language = {en} } @article{LangMonkman, author = {Lang, A. and Monkman, Gareth J.}, title = {An analysis of the electrical capacitance between two conducting spheres}, series = {Journal of Electrostatics}, volume = {108}, journal = {Journal of Electrostatics}, publisher = {Elsevier}, doi = {10.1016/j.elstat.2020.103518}, abstract = {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.}, language = {en} } @article{ChenZhangSongetal., author = {Chen, Rui and Zhang, Zhuo and Song, Ruizhou and Fang, Cheng and Sindersberger, Dirk and Monkman, Gareth J. and Guo, Jianglong}, title = {Time-dependent electroadhesive force degradation}, series = {Smart Materials and Structures}, volume = {29}, journal = {Smart Materials and Structures}, number = {5}, publisher = {IOP Publishing}, doi = {10.1088/1361-665X/ab79b5}, abstract = {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.}, language = {en} } @article{HaugVetterWeber, author = {Haug, Sonja and Vetter, Miriam and Weber, Karsten}, title = {Geb{\"a}udesanierung zwischen Energieeffizienz und Sozialvertr{\"a}glichkeit}, series = {TATuP - Zeitschrift f{\"u}r Technikfolgenabsch{\"a}tzung in Theorie und Praxis}, volume = {29}, journal = {TATuP - Zeitschrift f{\"u}r Technikfolgenabsch{\"a}tzung in Theorie und Praxis}, number = {3}, publisher = {oekom-Verlag}, issn = {2567-8833}, doi = {10.14512/tatup.29.3.56}, pages = {56 -- 63}, abstract = {Die Akzeptanz unter Bewohnern und Bewohnerinnen gewinnt bei hoch komplexen, technisch anspruchsvollen energetischen Sanierungen als „Innovationsmotor" zunehmend an Relevanz. Der Beitrag basiert auf zwei Fallstudien zur partizipativen Nutzereinbindung bei energetischen Sanierungen im genossenschaftlichen Wohnbau historischer Stadtquartiere in Regensburg. Neben einer sozialvertr{\"a}glichen Sanierung wurde jeweils ein hohes Maß an Energieeffizienz bei den technischen L{\"o}sungen ange-strebt. Haushaltsbefragungen und qualitative Interviews zeigen die hohe Akzeptanz von Sanierungsmaßnahmen, sofern die Senkung der Energiekosten die erh{\"o}hte Miete kompensiert. Abschließend werden Akzeptanzfaktoren wie Partizipation, Vertrauen, Sozialvertr{\"a}glichkeit und Autarkie er{\"o}rtert.}, subject = {Altbaumodernisierung}, language = {de} } @article{BringoutErbFrikel, author = {Bringout, Ga{\"e}l and Erb, Wolfgang and Frikel, J{\"u}rgen}, title = {A new 3D model for Magnetic Particle Imaging using realistic magnetic field topologies for algebraic reconstruction}, series = {Inverse Problems}, volume = {36}, journal = {Inverse Problems}, number = {12}, publisher = {IOP Publishing}, doi = {10.1088/1361-6420/abb446}, abstract = {We derive a new 3D model for magnetic particle imaging (MPI) that is able to incorporate realistic magnetic fields in the reconstruction process. In real MPI scanners, the generated magnetic fields have distortions that lead to deformed magnetic low-field volumes with the shapes of ellipsoids or bananas instead of ideal field-free points (FFP) or lines (FFL), respectively. Most of the common model-based reconstruction schemes in MPI use however the idealized assumption of an ideal FFP or FFL topology and, thus, generate artifacts in the reconstruction. Our model-based approach is able to deal with these distortions and can generally be applied to dynamic magnetic fields that are approximately parallel to their velocity field. We show how this new 3D model can be discretized and inverted algebraically in order to recover the magnetic particle concentration. To model and describe the magnetic fields, we use decompositions of the fields in spherical harmonics. We complement the description of the new model with several simulations and experiments, exploring the effects of magnetic fields distortion and reconstruction parameters on the reconstruction.}, language = {en} } @misc{Rauch, type = {Master Thesis}, author = {Rauch, Johannes}, title = {Entwicklung eines Regelverfahrens f{\"u}r einen optimierten und zentralen Blindleistungsabruf zur Beeinflussung des Blindleistungshaushalts von Mittelspannungsnetzen unter Einhaltung von Netzrestriktionen}, doi = {10.35096/othr/pub-659}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-6595}, school = {Ostbayerische Technische Hochschule Regensburg}, pages = {115}, abstract = {Die Energiewende f{\"u}hrt zu neuen Herausforderungen f{\"u}r Verteilungsnetzbetreiber hinsichtlich der Er-bringung von Systemdienstleistungen, der Integration weiterer Erzeugungsanlagen und Lasten sowie der Gew{\"a}hrleistung einer hohen Versorgungssicherheit und normgerechten Spannungsqualit{\"a}t. Die De-ckung der auftretenden Blindleistungsbedarfe seitens der Netzbetriebsmittel, Verbraucher und Erzeu-gungsanlagen gewinnt durch den Wegfall der Großkraftwerke f{\"u}r Netzbetreiber zunehmend an Bedeu-tung. Das Projekt SyNErgie besch{\"a}ftigt sich diesbez{\"u}glich mit der Entwicklung neuartiger Blindleis-tungsmanagementsysteme f{\"u}r Mittelspannungsnetze. Ziel ist es, das bisher ungenutzte, freie Blindleis-tungspotential betrieblicher Kompensationsanlagen und dezentraler Erzeugungsanlagen (allgemein: Blindleistungsquellen) zu nutzen, um die Blindleistungs{\"a}nderungsf{\"a}higkeit eines Verteilungsnetzes zu erh{\"o}hen. Diese Arbeit besch{\"a}ftigt sich mit der Entwicklung eines zentralen Blindleistungsregelsystems, bei dem Blindleistungsquellen auf Basis von „Optimal Power Flow"-Berechnungen {\"u}ber 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.}, language = {de} } @article{KeimParedesNonnetal., author = {Keim, Vincent and Paredes, Marcelo and Nonn, Aida and M{\"u}nstermann, Sebastian}, title = {FSI-simulation of ductile fracture propagation and arrest in pipelines}, series = {International Journal of Pressure Vessels and Piping}, volume = {182}, journal = {International Journal of Pressure Vessels and Piping}, number = {May}, publisher = {Elsevier}, doi = {10.1016/j.ijpvp.2020.104067}, abstract = {The fracture propagation and arrest control for pipelines transporting rich natural gases and high vapor pressure liquids is based on the Battelle Two-Curve Model (BTCM). Distinct limitations of this model were demonstrated for past and modern steels and gas mixtures. These can be related to the insufficient description of individual physical processes and interactions between the pipe material and transported mixture during the running ductile fracture. In the past, fluid-structure interaction (FSI) models enabled a more sophisticated, coupled analysis of the failure scenario. To quantify their capability of describing the multi-physical processes, the FSI models need to be verified by experimental data from full-scale burst tests (FSBT). Therefore, this paper deals with the simulation of five FSBTs from the literature on API grade X65 pipes with different pipe geometries, mixtures and initial conditions. The FSI is modeled by the coupled Euler-Lagrange (CEL) method. The modified Mohr-Coulomb (MMC) model is implemented in the CEL framework to describe the deformation and ductile fracture in the X65/L450 pipes. 3D Euler equations are used to calculate the mixture decompression with the GERG-2008 equation of state defining the volumetric behavior of a CO2-rich mixture, CH4 and H2. The extended model considers the effect of soil backfill on the pipe deformation and inertia. The numerical predictions agree well with the experimental findings in terms of the crack propagation speed and arrest length underlining the capability of the developed numerical tool.}, subject = {Bruchmechanik}, language = {en} } @techreport{RankHeberlSterner, author = {Rank, Daniel and Heberl, Michael and Sterner, Michael}, title = {Die CO2-Bilanz der OTH [Ostbayerischen Technische Hochschule Regenburg]}, language = {de} } @inproceedings{RillButzRill, author = {Rill, Daniel and Butz, Christiane and Rill, Georg}, title = {Dynamic Interaction of Heavy Duty Vehicles and Expansion Joints}, series = {Multibody Dynamics 2019, Proceedings of the 9th ECCOMAS Thematic Conference on Multibody Dynamics}, volume = {53}, booktitle = {Multibody Dynamics 2019, Proceedings of the 9th ECCOMAS Thematic Conference on Multibody Dynamics}, editor = {Kecskem{\´e}thy, Andr{\´e}s and Geu Flores, Francisco}, publisher = {Springer International Publishing}, address = {Cham}, isbn = {978-3-030-23131-6}, doi = {10.1007/978-3-030-23132-3_56}, pages = {471 -- 478}, abstract = {The "Smart Bridge (Intelligente Br{\"u}cke)" project cluster, initiated by the German Federal Highway Research Institute (Bundesanstalt f{\"u}r Straßenwesen, BASt) and the Federal Ministry of Transport and Digital Infrastructure (BMVI), focuses on "smart" monitoring devices that allow an efficient and economic maintenance management of bridge infrastructures. Among the participating projects, the one presented herein focuses on the development of a smart expansion joint, to assess the traffic parameters on site. This is achieved by measuring velocity and weight of crossing vehicles. In reference measurements, performed with a three-axle truck and a typical tractor semi-trailer combination with five axles in total, it was shown that the interaction between the vehicle and the expansion joint is highly dynamic and depends on several factors. To get more insight into this dynamic problem, a virtual test rig was set up. Although nearly all vehicle parameters had to be estimated, the simulation results conform very well with the measurements and are robust to vehicle parameter variations. In addition, they indicate a significant influence of the expansion joint dynamic to the peak values of the measured wheel loads, in particular on higher driving velocities. By compensating the relevant dynamic effects in the measurements, a "smart" data processing algorithm makes it possible to determine the actual vehicle weights in random traffic with reliability and appropriate accuracy.}, language = {en} } @inproceedings{RillArrietaCastro, author = {Rill, Georg and Arrieta Castro, Abel}, title = {A Novel Approach for Parametrization of Suspension Kinematics}, series = {Advances in Dynamics of Vehicles on Roads and Tracks: Proceedings of the 26th Symposium of the International Association of Vehicle System Dynamics (IAVSD 2019), August 12-16, 2019, Gothenburg, Sweden}, booktitle = {Advances in Dynamics of Vehicles on Roads and Tracks: Proceedings of the 26th Symposium of the International Association of Vehicle System Dynamics (IAVSD 2019), August 12-16, 2019, Gothenburg, Sweden}, editor = {Klomp, Matthijs and Bruzelius, Fredrik and Nielsen, Jens and Hillemyr, Angela}, publisher = {Springer International Publishing}, address = {Cham}, isbn = {978-3-030-38076-2}, doi = {10.1007/978-3-030-38077-9_210}, pages = {1848 -- 1857}, abstract = {n the automotive industry, simulations are needed to analyse the dynamics of vehicles and also of its main components and subsystems, e.g. tires, brakes and suspension systems. These simulations are required for an early-stage development and in consequence, they must deliver realistic results. Suspension systems plays a key role in comfort and safety of road vehicles. They usually consist of rigid links and force elements that are arranged with a specific topology. In addition, some of their functionalities are to carry the weight of the car and the passengers, and maintain a correct wheel alignment. In simulations involving suspension systems, lookup-tables are frequently used. They are obtained from a Kinematic and Compliance (KnC) test and then standardized for a specific vehicle simulation software. Nonetheless, lookup-tables require a reasonable number of characteristic points. Additionally, derivatives, interpolation, and extrapolation are not necessarily smooth. This produces results that depend on the interpolation technique and may be inaccurate. In this paper, a novel method called "design kinematics" is proposed. This method can describe the kinematic properties of almost any type of suspension systems. Comparisons with an analytic calculation and a KnC measurement shown that the design kinematics is able to represent the kinematic and compliance properties of suspension systems extremely well and very efficiently.}, language = {en} } @inproceedings{Rill, author = {Rill, Georg}, title = {TMeasy 6.0-A handling tire model that incorporates the first two belt eigenmodes}, series = {Proceedings of the XI International Conference on Structural Dynamics (EURODYN 2020): Athens, Greece, 23.11.2020 - 26.11.2020}, booktitle = {Proceedings of the XI International Conference on Structural Dynamics (EURODYN 2020): Athens, Greece, 23.11.2020 - 26.11.2020}, publisher = {EASD Procedia}, doi = {10.47964/1120.9054.18673}, pages = {676 -- 689}, abstract = {TMeasy 6.0, an extension to the standard TMeasy tire model of version 5.3, takes the relevant first two rigid body eigenmodes of the belt into consideration. These modes represent the in plane longitudinal and rotational movements of the belt relative to the rim. The dynamics of the longitudinal force is of higher order then and reproduces the tire wheel vibrations, required for indirect tire-pressure monitoring systems (iTPMS), sufficiently well. A tailored implicit solver, which takes the stiff coupling between the longitudinal force and the belt motions into account, still provides real-time performance in addition. Simulation examples show that a rigid body vehicle model equipped with TMeasy 6.0 makes it possible to investigate second generation indirect tire-pressure monitoring systems.}, language = {en} } @book{RillArrietaCastro, author = {Rill, Georg and Arrieta Castro, Abel}, title = {Road Vehicle Dynamics}, publisher = {CRC Press}, address = {Boca Raton, Fla.}, isbn = {9780429244476}, doi = {10.1201/9780429244476}, abstract = {Road Vehicle Dynamics: Fundamentals and Modeling with MATLAB®, Second Edition combines coverage of vehicle dynamics concepts with MATLAB v9.4 programming routines and results, along with examples and numerous chapter exercises. Improved and updated, the revised text offers new coverage of active safety systems, rear wheel steering, race car suspension systems, airsprings, four-wheel drive, mechatronics, and other topics. Based on the lead author's extensive lectures, classes, and research activities, this unique text provides readers with insights into the computer-based modeling of automobiles and other ground vehicles. Instructor resources, including problem solutions, are available from the publisher.}, subject = {Fahrdynamik}, language = {en} } @inproceedings{KetterlHeinrichReitmeieretal., author = {Ketterl, Hermann and Heinrich, Tobias and Reitmeier, Torsten and Hoelscher, Clemens}, title = {Emissionsabh{\"a}ngige Leistungsregelung f{\"u}r BHKW's}, series = {Tagungsband AALE 2020: Automatisierung und Mensch-Technik-Interaktion, 17. Fachkonferenz, 4. bis 6. M{\"a}rz 2020, Leipzig}, volume = {2020}, booktitle = {Tagungsband AALE 2020: Automatisierung und Mensch-Technik-Interaktion, 17. Fachkonferenz, 4. bis 6. M{\"a}rz 2020, Leipzig}, editor = {J{\"a}kel, Jens and Thiel, Robert}, publisher = {VDE-Verlag}, isbn = {978-3-8007-5180-8}, pages = {7}, language = {de} } @article{BruniMeijaardRilletal., author = {Bruni, S. and Meijaard, J. P. and Rill, Georg and Schwab, A. L.}, title = {State-of-the-art and challenges of railway and road vehicle dynamics with multibody dynamics approaches}, series = {Multibody System Dynamics}, volume = {49}, journal = {Multibody System Dynamics}, number = {1}, publisher = {Springer}, doi = {10.1007/s11044-020-09735-z}, pages = {1 -- 32}, abstract = {A review of the current use of multibody dynamics methods in the analysis of the dynamics of vehicles is given. Railway vehicle dynamics as well as road vehicle dynamics are considered, where for the latter the dynamics of cars and trucks and the dynamics of single-track vehicles, in particular motorcycles and bicycles, are reviewed. Commonalities and differences are shown, and open questions and challenges are given as directions for further research in this field.}, language = {en} } @article{SternerBauer, author = {Sterner, Michael and Bauer, Franz}, title = {Power-to-X im Kontext der Energiewende und des Klimaschutzes in Deutschland}, series = {Chemie-Ingenieur-Technik}, volume = {92}, journal = {Chemie-Ingenieur-Technik}, number = {1-2}, publisher = {Wiley}, issn = {0009-286X}, doi = {10.1002/cite.201900167}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-11669}, pages = {85 -- 90}, abstract = {Um den Einfluss verschiedener Power-to-X-Verfahren auf die Transformation des deutschen Energiesystems und das Erreichen der Klimaschutzziele zu {\"u}berpr{\"u}fen, wurde ein sektor{\"u}bergreifendes Energiesystemmodel entwickelt. Die daraus gewonnenen Ergebnisse zeigen: F{\"u}r 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.}, subject = {Power-to-Gas}, language = {de} } @article{MikhaeilGadererDawoud, author = {Mikhaeil, Makram and Gaderer, Matthias and Dawoud, Belal}, title = {On the development of an innovative adsorber plate heat exchanger for adsorption heat transformation processes; an experimental and numerical study}, series = {Energy}, volume = {207}, journal = {Energy}, number = {September}, publisher = {Elsevier}, doi = {10.1016/j.energy.2020.118272}, pages = {1 -- 13}, abstract = {An innovative adsorber plate heat exchanger (APHE), which is developed for application in adsorption heat pumps, chillers and thermal energy storage systems, is introduced. A test frame has been constructed as a representative segment of the introduced APHE for applying loose grains of AQSOA-Z02. Adsorption kinetic measurements have been carried out in a volumetric large-temperature-jump setup under typical operating conditions of adsorption processes. A transient 2-D model is developed for the tested sample inside the setup. The measured temporal uptake variations with time have been fed to the model, through which a micro-pore diffusion coefficient at infinite temperature of 2 E-4 [m2s-1] and an activation energy of 42.1 [kJ mol-1] have been estimated. A 3-D model is developed to simulate the combined heat and mass transfer inside the APHE and implemented in a commercial software. Comparing the obtained results with the literature values for an extruded aluminium adsorber heat exchanger coated with a 500 μm layer of the same adsorbent, the differential water uptake obtained after 300 s of adsorption (8.2 g/100 g) implies a sound enhancement of 310\%. This result proves the great potential of the introduced APHE to remarkably enhance the performance of adsorption heat transformation appliances.}, language = {en} } @article{MonkmanStrieglPremetal., author = {Monkman, Gareth J. and Striegl, Birgit and Prem, Nina and Sindersberger, Dirk}, title = {Electrical Properties of Magnetoactive Boron-Organo-Silicon Oxide Polymers}, series = {Macromolecular Chemistry and Physics}, volume = {221}, journal = {Macromolecular Chemistry and Physics}, number = {4}, publisher = {Wiley}, doi = {10.1002/macp.201900342}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-26488}, pages = {1 -- 8}, abstract = {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.}, language = {en} } @article{PremSindersbergerMonkman, author = {Prem, Nina and Sindersberger, Dirk and Monkman, Gareth J.}, title = {Infrared spectral analysis of low concentration magnetoactive polymers}, series = {Journal of Applied Polymer Science}, volume = {137}, journal = {Journal of Applied Polymer Science}, number = {7}, publisher = {Wiley}, organization = {WILEY}, issn = {1097-4628}, doi = {10.1002/app.48366}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-25913}, pages = {1 -- 7}, abstract = {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.}, language = {en} } @article{MetschSchmidtSindersbergeretal., author = {Metsch, P. and Schmidt, H. and Sindersberger, Dirk and Kalina, K. A. and Brummund, J. and Auernhammer, G{\"u}nter and Monkman, Gareth J. and K{\"a}stner, Markus}, title = {Field-Induced Interactions in Magneto-Active Elastomers}, series = {Smart Materials and Structures}, volume = {29}, journal = {Smart Materials and Structures}, number = {8}, publisher = {IOPscience}, doi = {10.1088/1361-665X/ab92dc}, pages = {1 -- 10}, abstract = {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.}, language = {en} } @inproceedings{FrauenschlaegerDentgenMottok, author = {Frauenschl{\"a}ger, Tobias and Dentgen, Manuel and Mottok, J{\"u}rgen}, title = {Systemarchitektur eines Sicherheitsmoduls im Energiesektor}, series = {Tagungsband 2. Symposium Elektronik und Systemintegration ESI 2020: "Intelligente Systeme und ihre Komponenten: Forschung und industrielle Anwendung"}, booktitle = {Tagungsband 2. Symposium Elektronik und Systemintegration ESI 2020: "Intelligente Systeme und ihre Komponenten: Forschung und industrielle Anwendung"}, address = {Landshut}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:860-opus4-2092}, pages = {29 -- 38}, abstract = {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 f{\"u}r {\"U}berwachungsfunktionen {\"u}bertragen. In den aktuellen Netzwerkarchitekturen findet diese Kommunikation ohne eine kryptografische Absicherung statt, was einen Angriffspunkt f{\"u}r gezielte Attacken und damit eine potenzielle Gef{\"a}hrdung 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 erf{\"u}llen, wurde eine spezielle Systemarchitektur auf Basis einer Aufgabenteilung entworfen. Diese Architektur und korrespondierende Designentscheidungen werden pr{\"a}sentiert.}, language = {de} } @inproceedings{MuehlbauerRablRottengruber, author = {M{\"u}hlbauer, Christian and Rabl, Hans-Peter and Rottengruber, Hermann}, title = {Akustische Analyse und Optimierung von mechatronischen Kraftstoffeinspritzsystemen}, series = {Tagungsband DAGA 2019 - 45. Jahrestagung f{\"u}r Akustik, 18.-21. M{\"a}rz 2019, Rostock}, booktitle = {Tagungsband DAGA 2019 - 45. Jahrestagung f{\"u}r Akustik, 18.-21. M{\"a}rz 2019, Rostock}, publisher = {Deutsche Gesellschaft f{\"u}r Akustik}, address = {Berlin}, isbn = {978-3-939296-14-0}, pages = {647 -- 650}, language = {de} } @inproceedings{SchneiderHotsLuftetal., author = {Schneider, Sebastian and Hots, Jan and Luft, Tommy and Rottengruber, Hermann and Verhey, Jesko L. and Rabl, Hans-Peter}, title = {Entwicklung einer empirischen Formel zur Bewertung der Tickerger{\"a}uschanteile von Motorger{\"a}uschen}, series = {DAGA 2019 - 45. Jahrestagung f{\"u}r Akustik, 8.-21. M{\"a}rz 2019, Rostock}, volume = {45}, booktitle = {DAGA 2019 - 45. Jahrestagung f{\"u}r Akustik, 8.-21. M{\"a}rz 2019, Rostock}, publisher = {Deutsche Gesellschaft f{\"u}r Akustik e.V.}, isbn = {978-3-939296-14-0}, pages = {643 -- 646}, language = {de} } @inproceedings{RiegerMuehlbauerWeberetal., author = {Rieger, Anna and M{\"u}hlbauer, Christian and Weber, Rainer and Rabl, Hans-Peter}, title = {Measures to Address the Dissonance Perception of Multiple Tonal Components in Sounds}, series = {DAGA 2019 - 45. Jahrestagung f{\"u}r Akustik, 18.-21. M{\"a}rz 2019, Rostock}, volume = {45}, booktitle = {DAGA 2019 - 45. Jahrestagung f{\"u}r Akustik, 18.-21. M{\"a}rz 2019, Rostock}, publisher = {Deutsche Gesellschaft f{\"u}r Akustik e.V.}, pages = {375 -- 378}, language = {en} } @misc{SchwanzerDietrichGadereretal., author = {Schwanzer, Peter and Dietrich, Markus and Gaderer, Matthias and Rabl, Hans-Peter}, title = {Monitoring von Partikelfiltern f{\"u}r den Einsatz in Fahrzeugen mit direkt- einspritzenden Ottomotoren mit einer Radio-Frequenz (RF-) Antenne}, series = {Kolloquium des Bayerischen Wissenschaftsforum}, journal = {Kolloquium des Bayerischen Wissenschaftsforum}, language = {de} } @misc{SchwanzerDietrichHaftetal., author = {Schwanzer, Peter and Dietrich, Markus and Haft, Gerhard and Gaderer, Matthias and Rabl, Hans-Peter}, title = {Oxidation Kinetics Determination of GDI Engine Soot by a Radio-Frequency Sensor}, series = {23rd Conference on Combustion Generated Nanoparticles 2019, June 17-20, Z{\"u}rich, Switzerland}, journal = {23rd Conference on Combustion Generated Nanoparticles 2019, June 17-20, Z{\"u}rich, Switzerland}, language = {en} } @article{SindersbergerPremMonkman, author = {Sindersberger, Dirk and Prem, Nina and Monkman, Gareth J.}, title = {Self-assembling structure formation in low-density magnetoactive polymers}, series = {Journal of Applied Polymer Science}, volume = {137}, journal = {Journal of Applied Polymer Science}, number = {3}, publisher = {Wiley}, doi = {10.1002/app.48291}, abstract = {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.}, language = {en} } @inproceedings{ReindlMeierNiemetz, author = {Reindl, Andrea and Meier, Hans and Niemetz, Michael}, title = {Software Framework for the Simulation of a Decentralized Battery Management System Consisting of Intelligent Battery Cells}, series = {2019 IEEE Student Conference on Research and Development (SCOReD), 15-17 Oct. 2019, Bandar Seri Iskandar, Malaysia}, booktitle = {2019 IEEE Student Conference on Research and Development (SCOReD), 15-17 Oct. 2019, Bandar Seri Iskandar, Malaysia}, doi = {10.1109/SCORED.2019.8896284}, pages = {75 -- 80}, abstract = {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.}, language = {en} } @inproceedings{HopkinsHopfenspergerMellor, author = {Hopkins, Andrew and Hopfensperger, Bernhard and Mellor, Phil}, title = {DC-link Capacitor Reduction in Low Voltage and High Power Integrated Modular Motor Drives}, series = {2019 IEEE Energy Conversion Congress and Exposition (ECCE), 29 Sept.-3 Oct. 2019, Baltimore, MD, USA}, booktitle = {2019 IEEE Energy Conversion Congress and Exposition (ECCE), 29 Sept.-3 Oct. 2019, Baltimore, MD, USA}, doi = {10.1109/ECCE.2019.8913213}, pages = {3208 -- 3214}, abstract = {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.}, language = {en} } @inproceedings{ScharfenbergElisHofmann, author = {Scharfenberg, Georg and Elis, Ludek and Hofmann, Gerhard}, title = {New Design Methodology - Using VHDL-AMS Models to Consider Aging Effects in Automotive Mechatronic Circuits for Safety Relevant Functions}, series = {2019 International Conference on Applied Electronics (AE), 10-11 Sept. 2019, Pilsen, Czech Republic}, booktitle = {2019 International Conference on Applied Electronics (AE), 10-11 Sept. 2019, Pilsen, Czech Republic}, doi = {10.23919/AE.2019.8867034}, pages = {1 -- 5}, abstract = {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.}, language = {en} } @inproceedings{BrkicCeranElmoghazyetal., author = {Brkic, Jovan and Ceran, Muaz and Elmoghazy, Mohamed and Kavlak, Ramazan and Haumer, Anton and Kral, Christian}, title = {Open Source PhotoVoltaics Library for Systemic Investigations}, series = {Proceedings of the 13th International Modelica Conference, March 4-6, 2019, Regensburg, Germany}, booktitle = {Proceedings of the 13th International Modelica Conference, March 4-6, 2019, Regensburg, Germany}, publisher = {Link{\"o}ing University Electronic Press}, doi = {10.3384/ecp1915741}, pages = {41 -- 50}, abstract = {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.}, language = {en} } @inproceedings{AlexanderHaumer, author = {Alexander, Grimm and Haumer, Anton}, title = {Parametrization Of A Simplified Physical Battery Model}, series = {Proceedings of the 13th International Modelica Conference, March 4-6, 2019, Regensburg, Germany}, booktitle = {Proceedings of the 13th International Modelica Conference, March 4-6, 2019, Regensburg, Germany}, publisher = {Link{\"o}ing University Electronic Press}, doi = {10.3384/ecp19157215}, pages = {215 -- 220}, abstract = {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.}, language = {en} } @inproceedings{DiamantidisSykora, author = {Diamantidis, Dimitris and S{\´y}kora, Miroslav}, title = {Implementing Information Gained through Structural Health Monitoring - Proposal for Standards}, series = {13th International Conference on Applications of Statistics and Probability in Civil Engineering, Mai 2019, Seoul, Korea}, booktitle = {13th International Conference on Applications of Statistics and Probability in Civil Engineering, Mai 2019, Seoul, Korea}, abstract = {With exception of a few issues such as design by testing, current standards do not include guidelines on the use and the quantification of value of additional information gained through Structural Health Monitoring (SHM). This contribution summarizes a recently developed draft of the guideline for practicing engineers in the framework of the EU-COST project 1402 and illustrates its application in engineering decision-making. Besides continuous and periodic monitoring, visual inspection, non-destructive evaluation and proof loading are included herein as a simple form of SHM. The guideline is independent of a type of structure, construction materials, loading, and of environmental conditions. It aims at a wide field of application including design of new structures, assessment of existing structures and type specific monitoring of a population of structures. The decision process related to the use of SHM is presented first together with relevant decision objectives and variables. Performance indicators are summarized and discussed with respect to the performance objectives. The evaluation of monitoring strategies based on life cycle costs is exposed and the selection of optimal intervention actions including safety measures is shown in representative case studies. The results demonstrate the potential of the use of monitoring to support engineering decisions and reflect though the practical benefits from the application of the guideline.}, language = {en} } @inproceedings{Briem, author = {Briem, Ulrich}, title = {Neue Methode zur Bestimmung der Biegesteifigkeit von Drahtseilen}, series = {Der Kran - Leistungssteigerung, Leichtbau und Automatisierung : 27. Internationale Kranfachtagung 2019 : Begleitband zur Kranfachtagung am 07. M{\"a}rz 2019 in Bochum}, booktitle = {Der Kran - Leistungssteigerung, Leichtbau und Automatisierung : 27. Internationale Kranfachtagung 2019 : Begleitband zur Kranfachtagung am 07. M{\"a}rz 2019 in Bochum}, editor = {Scholten, Jan}, publisher = {Selbstverlag der Ruhr-Universit{\"a}t Bochum}, address = {Bochum}, isbn = {3-89194-226-5}, pages = {103 -- 112}, language = {de} } @inproceedings{Briem, author = {Briem, Ulrich}, title = {Lebensdauerverhalten verdichteter Seildr{\"a}hte}, series = {Ilmenauer Drahttag 2019}, booktitle = {Ilmenauer Drahttag 2019}, publisher = {ISLE Steuerungstechnik und Leistungselektronik}, address = {Ilmenau}, isbn = {978-3- 938843-96-3}, pages = {73 -- 82}, language = {de} } @inproceedings{BuettnerBohigasBoladerasGottschalketal., author = {B{\"u}ttner, Johannes and Bohigas Boladeras, Pere and Gottschalk, Philipp and Kucera, Markus and Waas, Thomas}, title = {Performance Isolation of Co-located Workload in a Container-based Architecture for Automobile}, series = {9th International Conference on Ambient Computing, Applications, Services and Technologies 2019, 22-26.09.2019, Porto, Portugal}, booktitle = {9th International Conference on Ambient Computing, Applications, Services and Technologies 2019, 22-26.09.2019, Porto, Portugal}, isbn = {978-1-61208-739-9}, pages = {31 -- 37}, abstract = {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.}, language = {en} } @misc{Waas, author = {Waas, Thomas}, title = {Energy Monitoring and Saving in Medium-Sized Companies}, series = {5th International Congress on Energy Efficiency \& Energy Related Materials (ENEFM 2019), Gebze Technical University, Turkey, Book of Abstracts}, journal = {5th International Congress on Energy Efficiency \& Energy Related Materials (ENEFM 2019), Gebze Technical University, Turkey, Book of Abstracts}, editor = {Ahmet, Yavuz Oral and Zehra, Banu Oral and Mehmet, Sezer and Mehmet, Emre Ak{\"o}z and Seda, Kol and Onur, Alp and Aksan, Vala and Can, A{\c{s}}kan and Gamze, Sekicek}, pages = {21}, language = {en} } @article{BraunRablMatysik, author = {Braun, Peter and Rabl, Hans-Peter and Matysik, Frank-Michael}, title = {Investigations on the Liquid-Phase Decomposition of AdBlue Urea for the Selective Catalytic Reduction Process}, series = {Chemie Ingenieur Technik}, volume = {91}, journal = {Chemie Ingenieur Technik}, number = {7}, publisher = {Wiley}, doi = {10.1002/cite.201800055}, pages = {961 -- 968}, abstract = {Difficulties in decomposing AdBlue to ammonia limit the applicability of selective catalytic reduction systems at low exhaust temperatures. Investigations on the decomposition of AdBlue in the liquid phase under elevated pressure at temperatures up to 165 degrees C were carried out. Besides effects of inorganic catalysts, the impact of pH on urea decomposition was examined. After dissolution in aqueous phase, the compounds ZnO, WO3, and MoO3 were found to be effective in liquid-phase AdBlue decomposition. However, the efficiency was dropping significantly over few hours. Decomposition of AdBlue urea was also found to be favored for alkaline and acidic conditions.}, language = {en} }