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 - JOUR A1 - Haug, Sonja A1 - Vetter, Miriam A1 - Weber, Karsten T1 - Gebäudesanierung zwischen Energieeffizienz und Sozialverträglichkeit BT - Zwei empirische Fallstudien JF - TATuP - Zeitschrift für Technikfolgenabschätzung in Theorie und Praxis N2 - 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 sozialverträglichen Sanierung wurde jeweils ein hohes Maß an Energieeffizienz bei den technischen Lösungen ange-strebt. Haushaltsbefragungen und qualitative Interviews zeigen die hohe Akzeptanz von Sanierungsmaßnahmen, sofern die Senkung der Energiekosten die erhöhte Miete kompensiert. Abschließend werden Akzeptanzfaktoren wie Partizipation, Vertrauen, Sozialverträglichkeit und Autarkie erörtert. T2 - Building restoration between energy efficiency and user acceptance KW - Altbaumodernisierung KW - Energieeinsparung KW - Sozialverträglichkeit KW - Fallstudie KW - energy-efficient building restoration KW - user acceptance KW - household survey KW - historic quarter KW - renewable energy Y1 - 2020 U6 - https://doi.org/10.14512/tatup.29.3.56 SN - 2567-8833 VL - 29 IS - 3 SP - 56 EP - 63 PB - oekom-Verlag ER - TY - CHAP A1 - Weber, Karsten A1 - Haug, Sonja T1 - Automatisiertes Fahren: Evolutionäre Weiterentwicklung statt Disruption T2 - Vierte Jahreskonferenz des Netzwerks INDIGO zum Thema "Mobilität", 23.11.2018, , TH Deggendorf Y1 - 2018 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 - JOUR A1 - Selmair, Maximilian A1 - Maurer, Tobias A1 - Lai, Chun-Han A1 - Grant, David T1 - Enhancing the efficiency of charging & parking processes for Autonomous Mobile Robot fleets BT - A simulative evaluation JF - Journal of Power Sources N2 - The allocation of tasks to Autonomous Mobile Robots in a production setting in combination with the most efficient parking and charging processes are the focus of this paper. This study presents a simulative evaluation of the theoretical allocation methods developed in Selmair and Maurer (2020) combined with either hard or dynamic availability rules to ascertain the most efficient parameters of an Autonomous Mobile Robot System. In order to quantify this efficiency, the following Key Performance Indicator (KPI) were considered: number of delayed orders, driven fleet metres and the percentage of available Autonomous Mobile Robot as determined by their state of charge. Additionally, as an alternative energy source, a fast-charging battery developed by Battery Streak Inc. was included in this study. The results show that, in comparison to a conventional and commonly used trivial strategy, our developed strategies provide superior results in terms of the relevant KPI. KW - AMR KW - Autonomous Mobile Robot KW - Battery charging KW - Battery management systems KW - Benchmarking KW - Fleet operations KW - Mobile robots KW - NAVIGATION KW - Secondary batteries KW - Vehicle Fleet Charging Y1 - 2022 U6 - https://doi.org/10.1016/j.jpowsour.2021.230894 VL - 521 IS - 3 PB - Elsevier 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 - Boccara, R. A1 - Diamantidis, Dimitris A1 - Sýkora, Miroslav T1 - Optimal design of ground-mounted solar systems T2 - Safety and reliability : methodology and applications : proceedings of the European Safety and Reliability Conference, ESREL 2014, Wrocław, Poland, 14-18 September 2014 N2 - Solar energy represents a clean, natural and sustainable source of energy. Solar photovoltaic panels can be installed on roofs of structures or in the ground. This contribution focusses on ground-mounted systems, which are presently widely implemented. At present limited guidelines on the design of solar ground-mounted structures are available. Usually standards for the design of normal buildings are applied. However, the design of ground-mounted structures significantly differs from common structural design by: (1) a lower design lifetime (20-25 years) is accepted; (2) failure is not associated with the loss of human life; (3) resistance uncertainties need due attention; (4) uplift wind forces dominating structural reliability are associated with a large scatter. That is why the reliability analysis and optimal design of ground-mounted solar systems is investigated herein. The failure costs and especially their ratio to the initial costs are analyzed considering the data provided from the industry. Probabilistic reliability analyses are carried out and optimum design levels are computed for representative cost ratios. The optimal target reliability depends on the ratio between failure and initial costs; reliability index of 3.5 corresponds to a reasonable cost ratio of 10. KW - Dach KW - Montagesystem KW - Montiergerät KW - nachhaltiges Sourcing KW - Solarenergie KW - Solarmodul KW - Windkraft (Energiequelle) Y1 - 2014 SN - 978-1-138-02681-0 SP - 2175 EP - 2181 PB - CRC Press CY - Boca Raton ER - TY - CHAP A1 - Kaspar, Marcel A1 - Kleiner, Florian A1 - Rabl, Hans-Peter T1 - Online-Analyse und Optimierung der Schmierölverdünnung bei direkteinspritzenden Ottomotoren T2 - 7. VDI-Fachtagung mit Fachausstellung Zylinderlaufbahn, Kolben, Pleuel : Baden-Baden, 03. und 04. Juni 2014 N2 - Bei Ottomotoren mit Direkteinspritzung besteht beim Kaltstart, den Warmlaufphasen und auch durch den Einfluss anderer Parameter wie z. B. des Einspritzzeitpunkts oder des Einspritzdrucks die Problematik, dass Kraftstoff an die Zylinderlaufbahn aufgetragen wird und sich mit dem Motoröl vermischen kann. Eine Verstärkung dieses Kraftstoffauftrags ist unter anderem der Verschiebung der Motorbetriebspunkte zu höheren Mitteldrücken und damit einem Wirkungsgrad optimaleren Betrieb geschuldet. Eine Veränderung der physikalischen und chemischen Eigenschaften des Motoröls durch die Verdünnung mit Kraftstoff ist die Folge. Durch die Verringerung der Viskosität des Motoröls kann es zu einer verminderten Schmierwirkung des Öls kommen, die im schlimmsten Fall zur Schädigung des Motors führt. Existierende Offline-Analysemethoden die zeitintensive Laboranalysen nach sich ziehen, als auch Online-Messverfahren die nicht den technischen Anforderungen hinsichtlich Genauigkeit und einer kurzen Messdauer entsprechen, stellen aktuell die einzigen Messmethoden zur Bestimmung der Schmierölverdünnung dar. Durch neue Entwicklungstrends bei Ottomotoren ist es jedoch unbedingt notwendig, die Mechanismen des Kraftstoffein- und -austrags in das und aus dem Motoröl genauer zu untersuchen. Mit der an der OTH Regensburg neu entwickelten Messtechnik wurde eine Vorgehensweise erarbeitet, mit der die zeitlichen Verläufe des Kraftstoffein- und -austragsverhaltens bei Ottomotoren quantitativ in kurzer Zeit bestimmt und optimiert werden können. Especially at cold start and the warm-up operation GDI engines have an issue with oil dilution. Parameters such as injection timing and injection pressure impact the entry of fuel in the engine oil as well. With the adjustment of engine operating points to higher mean effective pressures resulting in downsizing concepts also an additional increase of fuel entry occurs. Fuel gets into the oil pan and is mixed with the engine oil so that the physical and chemical properties of the engine oil are changed. With the reduction of engine oil viscosity due to fuel entry a reduced lubricating effect can be caused. In the worst case damage to the engine occurs, To determine oil dilution online and offline measurement methods exist. A rather long analysis time in the laboratory is a disadvantage of the offline methods. Online methods are not correlating with technical requirements in terms of accuracy and a short measurement time. New trends in the development of gasoline engines require investigations of fuel in oil sorption and desorption processes. A new measurement technique which is developed at the OTH Regensburg enables to determine quantitative fuel in oil sorption and desorption processes. With this technique a procedure was generated to measure the oil dilution at gasoline engines and optimize them in a short time. KW - Direkteinspritzerottomotor KW - Direkteinspritzung KW - Kaltstart KW - Kraftstoff KW - Motoröl KW - Online-Analyse KW - Online-Messverfahren KW - Ottomotor KW - Viskositätsverringerung Y1 - 2014 SN - 978-3-18-092230-0 SP - 65 EP - 77 PB - VDI-Verlag CY - Düsseldorf ER - TY - JOUR A1 - Keim, Vincent A1 - Marx, P. A1 - Nonn, Aida A1 - Münstermann, Sebastian T1 - Fluid-structure-interaction modeling of dynamic fracture propagation in pipelines transporting natural gases and CO2-mixtures JF - International Journal of Pressure Vessels and Piping N2 - As part of current design standards, the Battelle Two-Curve Model (BTCM) is still widely used to predict and secure ductile crack arrest in gas transmission pipelines. For modern linepipe steels and rich natural gases or CO2 mixtures, the BTCM might lead to incorrect predictions. On the one hand, it suffers from the insufficient description of the individual physical processes in the pipe material and fluid itself. Furthermore, the model does not account for fluid-structure-interaction (FSI) effects during simultaneous running-ductile fracture (RDF) and mixture decompression. Numerical FSI models allow for a more sophisticated, coupled analysis of the driving forces for the failure of pipelines. This paper deals with the development of an FSI model for the coupled prediction of 3D pressure profiles acting on the inner pipe wall during crack propagation. The coupled Euler-Lagrange (CEL) method is used to link the fluid and structure models. In a Lagrange formulation, the modified Bai-Wierzbicki (MBW) model describes the plastic deformation and ductile fracture as a function of the underlying stress/strain conditions. The fluid behavior is calculated in a 3D model space by Euler equations and the GERG-2008 reference equation of state (EOS). The coupled CEL model is used to predict the RDF in small-diameter pipe sections for different fluid mixtures. The calculated 3D pressure distributions ahead and behind the running crack tip (CT) significantly differ in axial and circumferential directions depending on the mixture composition. The predicted FSI between the pipe wall and fluid decompression in 3D CEL/FSI model provides reliable knowledge about the pressure loading of the pipeline during RDF. KW - Fluid-Struktur-Wechselwirkung KW - Rissausbreitung KW - Pipeline KW - Gas KW - Pipeline failure KW - Fluid-structure-interaction KW - CO2 decompression KW - Running ductile fracture Y1 - 2019 U6 - https://doi.org/10.1016/j.ijpvp.2019.103934 VL - 175 IS - August PB - Elsevier ER - TY - JOUR A1 - Keim, Vincent A1 - Nonn, Aida A1 - Münstermann, Sebastian T1 - Application of the modified Bai-Wierzbicki model for the prediction of ductile fracture in pipelines JF - International Journal of Pressure Vessels and Piping N2 - The complex mechanical and corrosive loads of modern pipeline systems transporting oil, natural gas and CO2 impose steadily increasing requirements on material properties. The majority of current design standards still limit the application of modern high toughness linepipe steels due to the simple specification of material requirements in terms of energy levels from Charpy impact or Battelle Drop-Weight-Tear (BDWT) tests. In consequence, research activities have been conducted recently aiming at developing modified or novel experimental methods for the characterization of the ductile fracture behavior. To quantify the effects of various parameters on fracture behavior and derive suitable correlations, it is necessary to accompany these activities by numerical simulations with appropriate ductile damage models. In this paper, the MBW model is applied to study the structural behavior of pipelines in ductile fracture regime. Due to its precise incorporation of the underlying load conditions, the damage model is successfully used to simulate the slant fracture behavior in Battelle Drop weight tear test specimens and pipe sections. In comparison to ductile damage models applied in former studies, namely the Gurson-Tvergaard-Needleman and Cohesive Zone model, the presented numerical methodology allows for a more detailed investigation of loading, material and geometry effects on fracture and crack arrest behavior of pipelines. KW - Running ductile fracture KW - Stress state conditions KW - MBW model KW - Pipeline failure KW - Slant fracture Y1 - 2019 U6 - https://doi.org/10.1016/j.ijpvp.2019.02.010 VL - 171 IS - March SP - 104 EP - 116 PB - Elsevier ER -