TY - JOUR A1 - Bauer, Franz A1 - Sterner, Michael T1 - Impacts of lifestyle changes on energy demand and greenhouse gas emissions in Germany JF - Renewable and Sustainable Energy Reviews N2 - Most energy scenario studies typically focus on technological options and fuel substitution for decarbonising future energy systems. Lifestyle changes are rarely considered, although they can significantly reduce energy demand and climate change mitigation efforts. By using an energy system model, this study shows that it is possible to reduce final energy demand in Germany by 61 % in 2050 relative to 2019 levels, resulting in an annual per capita energy demand of 44 GJ for a representative country of the Global North. This goal can be achieved through a combination of technological measures and lifestyle changes without sacrificing a decent standard of living. Societal chances can eliminate reliance on not-yet-established negative emission technologies, reduce energy dependency, and reduce the need for energy-intensive hydrogen and e-fuels. Downsizing the energy system provides an opportunity for strengthening climate change mitigation, decrease material demand and reduce land use. KW - Climate change mitigation KW - Energy system modelling KW - Sufficiency KW - Lifestyle changes KW - Climate neutrality KW - Low energy demand KW - German climate targets Y1 - 2025 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-77682 SN - 1364-0321 N1 - Corresponding author der OTH Regensburg: Franz Bauer VL - 207 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Mühlbauer, Andreas A1 - Keiner, Dominik A1 - Gerhards, Christoph A1 - Caldera, Upeksha A1 - Sterner, Michael A1 - Breyer, Christian T1 - Assessment of technologies and economics for carbon dioxide removal from a portfolio perspective JF - International Journal of Greenhouse Gas Control N2 - Carbon dioxide removal (CDR) is essential to achieve ambitious climate goals limiting global warming to less than 1.5◦C, and likely for achieving the 1.5◦C target. This study addresses the need for diverse CDR portfolios and introduces the LUT-CDR tool, which assesses CDR technology portfolios aligned with hypothetical societal preferences. Six scenarios are described, considering global deployment limitations, techno-economic factors, area requirements, technology readiness, and storage security for various CDR options. The results suggest the feasibility of large-scale CDR, potentially removing 500–1750 GtCO2 by 2100 to meet the set climate targets. For a 1.0◦C climate goal, CDR portfolios necessitate 12.0–37.5% more primary energy compared to a scenario without CDR. Remarkably, funding a 1.0◦C target requires only 0.42–0.65% of the projected global gross domestic product. Bioenergy carbon capture and sequestration and rainfall-based afforestation play limited roles, while secure sequestration of captured CO2 via direct air capture, electricity-based carbon sequestration, and desalination-based afforestation emerge as more promising options. The study offers crucial techno-economic parameters for implementing CDR options in future energy-industry-CDR system analyses and demonstrates the tool’s flexibility through alternative assumptions. It also discusses limitations, sensitivities, potential tradeoffs, and outlines options for future research in the area of large-scale CDR. Y1 - 2025 U6 - https://doi.org/10.1016/j.ijggc.2024.104297 VL - 141 PB - Elsevier ER - TY - JOUR A1 - Keiner, Dominik A1 - Walter, Lukas A1 - Bogdanov, Dmitrii A1 - Peters, Ian Marius A1 - Breyer, Christian T1 - Assessing the impact of bifacial solar photovoltaics on future power systems based on capacity-density-optimised power plant yield modelling JF - Solar Energy N2 - Bifacial solar photovoltaic (PV) technology is currently taking over the solar PV module market, exceeding a 90% share in 2025. This important technology must be included in energy system modelling. This study provides a method for calculating the yield of monofacial and bifacial power plants in fixed-tilted, single-axis tracking, and east-west facing vertical setup. A novel method is introduced to maximise the capacity density of solar PV power plants without the need for detailed land cost for the most efficient use of the occupied area. The results indicate a 15-20% yield gain from single-axis tracking compared to fixed-tilted power plants, and a limited bifacial gain of up to 10% for most areas of the world. Higher bifacial gains are sporadically possible in specific conditions. Fixed-tilted systems show higher bifacial gains. Optimising tilt angles and row pitch would allow for 147 MW/ km2 capacity density today, though on average 70-110 MW/km2 can be achieved for 20.2% module efficiency. The impact on the power system, studied in a free cost optimisation scenario and forcing vertical bifacial PV scenario, implying agrivoltaics, is not significant with a +/- 10% change in total solar PV capacity, change in installed wind power of on average-10%, increase of installed battery capacity of on average 5%, and an on average changed levelised cost of electricity of-2% globally. Bifacial solar PV technology has been found to be beneficial but no game changer for future power systems; system improvements are widely possible underlining the important role of this technology. KW - Bifacial KW - Capacity density KW - Energy system modelling KW - Monofacial KW - photovoltaics KW - Power plant Y1 - 2025 U6 - https://doi.org/10.1016/j.solener.2025.113543 VL - 295 PB - Elsevier ER - TY - JOUR A1 - Doepfert, Markus A1 - Candas, Soner A1 - Kraus, Hermann A1 - Tzscheutschler, Peter A1 - Hamacher, Thomas T1 - Assessing the techno-economic benefits of LEMs for different grid topologies and prosumer shares JF - iScience N2 - The shift toward decentralized and renewable energy sources has introduced significant challenges to traditional power systems, necessitating innovative market designs. Local energy markets present a viable solution for integrating distributed energy resources such as photovoltaic systems, electric vehicles, and heat pumps. This study investigates the techno-economic implications of local energy markets compared to conventional market designs, focusing on their impact on average energy prices and operational peak power. Through comprehensive simulations across various grid topologies with varying penetration levels of the distributed energy resources, totaling 400 simulation setups, we demonstrate that local energy markets can enhance economic efficiency and grid stability with 99% of the scenarios boasting lower average energy prices and 80% lower operational peak power levels. The findings suggest that local energy markets can play a role in the future energy system, provided that additional infrastructure, management costs, and bureaucratic complexity are kept to a minimum. Y1 - 2025 U6 - https://doi.org/10.1016/j.isci.2025.112493 VL - 28 IS - 6 PB - Elsevier - Cell Press ER - TY - JOUR A1 - Dahmen, Victoria A1 - Bogenberger, Klaus A1 - Weikl, Simone T1 - Modellierung des Verkehrsmittelwahlverhaltens mittels erklärbarem Maschinellem Lernen JF - Straßenverkehrstechnik N2 - Die Modellierung der Verkehrsmittelwahl ist für die Vorhersage und das Verständnis des Mobilitätsverhaltens unerlässlich. Hierbei wurden in den letzten Jahren mit maschinellem Lernen vielversprechende Ergebnisse erzielt, insbesondere für XGBoost- und Random-Forest-Modelle. Aufgrund der zunehmenden Verwendung von Tracking-basierten Smartphone-Apps zur Aufzeichnung des Mobilitätsverhaltens, wenden wir diese Modelle auf einen solchen Datensatz an. Zudem analysieren wir eingehend deren Interpretierbarkeit. Wir kommen zu dem Schluss, dass das XGBoost-Modell am leistungsstärksten und dennoch erklärbar ist. Die von solchen Modellen gewonnenen Erkenntnisse können beispielsweise genutzt werden, um die Verkehrsmittelwahl für beliebige Quelle-Ziel-Paare vorherzusagen. Y1 - 2025 U6 - https://doi.org/10.53184/SVT2-2025-3 SN - 0039-2219 VL - 69 IS - 2 SP - 96 EP - 102 PB - Kirschbaum ER - TY - CHAP A1 - Reichel, Tobias A1 - Gerstner, Mathias A1 - Schiller, Leo A1 - Attenberger, Andreas A1 - Hackenberg, Rudolf A1 - Dološ, Klara T1 - A forensic analysis of GNSS spoofing attacks on autonomous vehicles T2 - Cloud Computing 2025 : The Sixteenth International Conference on Cloud Computing, GRIDs, and Virtualization, 06.-10. April 2025, Valencia N2 - Global Navigation Satellite Systems (GNSSs) are essential for modern technology, enabling precise geographic positioning in aviation, maritime shipping, and automotive systems. In the future, their role will be even more critical for autonomous vehicles, which rely on accurate localization for navigation and decision-making. However, the increasing connectivity of autonomous vehicles exposes them to cyber threats, including GNSS spoofing attacks, which manipulate location data to mislead onboard systems. As reliance on GNSS grows, so does the risk posed by spoofing attacks, making it a critical security concern. This paper describes GNSS spoofing attacks on autonomous vehicles, focusing on their detection both during and after an attack. Furthermore, we analyze data storage strategies to facilitate effective forensic analysis. We highlight the importance of position, signal, and camera data, which should be preserved to ensure a comprehensive forensic investigation. Finally, we suggest a simulation setup that enables studying which data could be used for a forensic investigation. Additionally, we examine established data frameworks and decide whether they are suitable for detecting GNSS spoofing attacks. Y1 - 2025 UR - https://www.thinkmind.org/articles/cloud_computing_2025_1_50_28008.pdf SN - 978-1-68558-258-6 SN - 2308-4294 SP - 32 EP - 39 ER - TY - RPRT A1 - Bergmeier, Sonja A1 - Bock, Maximilian A1 - Fischer, Lukas A1 - Flassig, Nathanael A1 - Hidvégi, Barnabás A1 - Bächer, Tim A1 - Hierl, Jonas A1 - Kaltenbach, Dominik A1 - Lackermeier, Florian A1 - Laubmann, Julia A1 - Liebl, Jonas A1 - Pirthauer, Tobias A1 - Reif, Robin A1 - Roider, Stefan ED - Fuhrmann, Thomas ED - Hipp, Susanne ED - Niemetz, Michael ED - Sterz, Oliver T1 - FMS-Berichte Wintersemester 2024/25 BT - Seminar zu aktuellen Themen der Elektro- und Informationstechnik T2 - FMS-Berichte Wintersemester 2024/25 N2 - Dieser Bericht entstand ursprünglich auf Initiative der Studierenden des damals neuen Masterstudiengangs „Elektro- und Informationstechnik (MEI)“ an der OTH Regensburg, 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 ist im Laufe der Veranstaltung geeignete Literatur zu einem individuellen Thema zu recherchieren, sind Veröffentlichungen auf ihre Relevanz hin zu beurteilen und letztendlich gilt es eine eigene Ausarbeitung basierend auf der Literaturrecherche zu erstellen und diese in einem Vortrag zu präsentieren. Parallel dazu wird im Theorieteil die entsprechende Hinführung zu den verschiedenen Elementen der Wissenschaftskommunikation vermittelt: • 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 Die präsentierten Themen beruhen nicht auf eigener Forschungstätigkeit, sondern sind als einführende Reviewartikel zum jeweiligen vorgegebenen technischen oder gesellschaftspolitischen Forschungsthema zu verstehen. T3 - Forschungsmethoden-Seminar - 9 KW - Elektrotechnik KW - Informationstechnik KW - Energietechnik KW - Literaturrecherche Y1 - 2025 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-83121 VL - 2024 IS - 9 CY - Regensburg ER - TY - INPR A1 - Meisinger, Alexander A1 - Hofrichter, Andreas A1 - Bauer, Franz A1 - Sterner, Michael T1 - Unlocking Potential Energy Partnerships in Europe: a Case Study on the Way to a Franco-German Energy Transition N2 - Global warming is already causing global destabilization. Geopolitical challenges fuel this instability and highlight the need for trusted energy partnerships to ensure energy security. To limit global warming and increase energy security, it is essential to take joint action on an international and global scale. The European Green Deal contributes to this. However, specific national actions are still needed. This research presents a way forward for a Franco-German energy transition and unlocks the potential of energy partnerships within Europe, using a cost-based, sector-coupled optimization model. Both countries are coupled via an isolated country optimization approach. Thus, the focus is on the development of each national energy system. The results highlight the increase of energy security in line with the European Green Deal. The main pillars of the energy transition are solar energy (32- 33%), wind energy (25-38%) and biogenic energy sources (13-27%). Nuclear power is being phased out in Germany and France. The results show that a Franco-German energy partnership has great potential. Overall, France can cost-effectively cover 25% of Germany’s hydrogen import needs (122 TWh) in 2050. At the same time, France can also benefit from the energy partnership in terms of economic growth and joint action to mitigate climate crisis. KW - Decarbonization KW - Energy partnership KW - Energy system modelling KW - Energy transition KW - European Green Deal KW - Power-to-X Y1 - 2025 U6 - https://doi.org/10.2139/ssrn.5251699 PB - SSRN ER - TY - RPRT A1 - Volkenhoff, Tobias A1 - Gerstenberger, Marcus A1 - Breitbarth, Lutz A1 - Carstensen, Christian A1 - Dölger, Reiner A1 - Feldges, Michael A1 - Hegewald, Jessica A1 - Mutzbauer, Johannes A1 - Rose, Martin A1 - Schopf, Hans Jürgen A1 - Schroth, Max A1 - Schwietering, Christoph A1 - Seidel, Christian A1 - Sievers, Ariane A1 - Spangler, Matthias A1 - Trupat, Stefan A1 - Üstün, Ellen T1 - H NBA - Hinweise zum Einsatz von Netzbeeinflussungsanlagen KW - Verkehrstechnik KW - Netzbeeinflussungsanlagen KW - Verkehrsmanagement Y1 - 2025 SN - 978-3-86646-434-8 IS - 310/1 PB - FGSV CY - Köln ET - Ausgabe 2025 ER - TY - JOUR A1 - Schumm, Leon A1 - Brown, Tom A1 - Abdel-Khalek, Hazem A1 - Ueckerdt, Falko A1 - Sterner, Michael A1 - Fioriti, David A1 - Parzen, Max T1 - The impact of temporal hydrogen regulation on hydrogen exporters and their domestic energy transition JF - Nature Communications N2 - As global demand for green hydrogen rises, potential hydrogen exporters move into the spotlight. While exports can bring countries revenue, large-scale on-grid hydrogen electrolysis for export can profoundly impact 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-benefits of domestic carbon dioxide mitigation and hydrogen exports, whereby exports can reduce market-based costs for domestic electricity consumers while mitigation reduces costs for hydrogen exporters. However, increasing hydrogen exports in a fossil-dominated system can substantially raise market-based costs for domestic electricity consumers, but surprisingly, temporal matching of hydrogen production can lower these costs by up to 31% with minimal impact on exporters. Here, we show that 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 Y1 - 2025 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-84857 N1 - Die Preprint-Version ist ebenfalls in diesem Repositorium verzeichnet unter: https://opus4.kobv.de/opus4-oth-regensburg/7272 VL - 16 PB - Nature CY - London ER - TY - RPRT A1 - Bhardwaj, Prakhar A1 - Hauer, Franziska A1 - Mücke, Vanessa A1 - Dotter, Caroline A1 - Haug, Sonja A1 - Weikl, Simone A1 - Weber, Karsten T1 - Recording and understanding multi- and intermodal mobility - a review N2 - The transition to sustainable mobility requires detailed knowledge of actual mobility behavior. Recording mobility behavior through conventional, aggregated, or retrospective survey methods (e.g., counting stations, travel diaries) may yield incomplete insights. In addition, these methods are often expensive, prone to error, or not scalable. The aim of this literature review is to provide a systematic overview of the current state of the literature on recording and analysis of individual mobility data and, based on this, to identify possible research gaps and potential. The exploratory literature review includes social science surveys on multi- and intermodal mobility behavior, as well as an overview of possible ways to analyze travel data. The focus of the latter is on identifying relevant data sources and methodological approaches for segmentation, identification of transport mode, and trip purpose determination. Results from recent studies show that sensor-based data collection alone is not sufficient to fully and accurately map mobility behavior. One possible solution is a “best-of-both-worlds” approach that combines passive, automatic mobility data collection via smartphone sensors with targeted user corrections and additions (“human-in-the-loop”) within an app. The literature review shows that this approach yields the best data quality. Combining mobility surveys with passive collection of mobility data provides a comprehensive, accurate, and complete overview of mobility behavior. KW - multimodal mobility KW - mobility Y1 - 2025 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-87427 CY - Regensburg ER - TY - GEN A1 - Birett, Falk A1 - Schumm, Leon A1 - Hofrichter, Andreas A1 - Heusgen, Valentin A1 - Rahim, Stefan T1 - Wasserstoffatlas Deutschland (Hydrogen Map) [Data set] N2 - Input files required for Hydrogen Map workflow in the project "Wasserstoffatlas Deutschland", funded by the BMBF. Y1 - 2025 U6 - https://doi.org/10.5281/zenodo.13960465 N1 - Further versions linked on Zenodo. ER - TY - CHAP A1 - Hinterreiter, Marion A1 - Brückl, Oliver A1 - Rauch, Johannes ED - Schulz, Detlef T1 - Methodology for long-term reactive power forecasts of medium-voltage grids T2 - NEIS 2025 : Conference on Sustainable Energy Supply and Energy Storage Systems, Hamburg, September 15 – 16, 2025 N2 - Understanding and assessing the long-term behavior of reactive power is crucial for power system planning and invest-ment decisions. This is particularly growing relevant for the lower voltage-grid levels, which are gaining importance due to significant changes in grid behavior, operational strategies, energy generation and consumption patterns. Currently, standardized methodologies for forecasting reactive power in medium-voltage grids are lacking, creating a gap in research and practical applications. To optimize grid investments and expansions, informed decisions based on reliable research and accurate forecasts are essential. This paper presents a methodology for long-term reactive power forecasting in me-dium-voltage grids, introducing a new approach to account for low- and medium-voltage grid interactions while address-ing common challenges like limited available grid data and scenario framework definition. The aim of the forecast is the future reactive power behaviour of a medium-voltage-grid at the high-voltage side of the high-voltage to medium-voltage transformer. The medium-voltage-level is modelled using a grid model approach, while low-voltage grids are being mod-elled using generic distribution grids. A 209-bus medium-voltage-grid model is used as an application example and to provide two exemplary use cases for a reactive power forecast for 2045. KW - reactive power KW - forecasting KW - long-term KW - medium-voltage level KW - grid level interaction Y1 - 2025 SN - 978-3-8007-6633-8 SP - 218 EP - 223 PB - VDE Verlag ER - TY - CHAP A1 - Stadler, Andreas A1 - Kraus, Hermann A1 - Brückl, Oliver ED - Technische Universität München, T1 - Proposing an Optimization Model for a techno-economic Evaluation of Energy Storage Systems T2 - PESS 2025 – IEEE Power and Energy Student Summit, October 08 – 10, 2025 in Munich, Germany N2 - During the global energy crisis in 2022, electricity prices increased drastically. This lead, together with an overall higher price volatility to possibly higher electrical energy storage system (ESS) profitability. To test if the investment in an ESS can now be more profitable, an approach for a techno-economic evaluation of ESS is presented in this paper, using an optimization algorithm to determine the optimal way of covering a load flow profile with electricity trading products on the electricity market with and without the use of an energy storage system. The cost differences between using or not using the storage system are assumed to be the profits of the ESS, which must exceed the (interest-bearing) investment costs over its lifetime. The correct way of operation of the optimization model is validated and several storage sizes and capacities as well as several years of the electricity market data was analyzed, once with a perfect forecast of all prices of the electricity trading products and once with a forecast based on the previous years purchasing strategy. The results show that, using the prognosis and a 2 % p.a. interest rate, only the storage combinations for 2.5 MWh/ 2.5 MW and 1 MWh/ 1 MW show profitability in 2023, whereas 2017 and 2020 show no profitability. KW - energy storage systems KW - techno economic evaluation KW - electricity trading KW - optimization KW - ess profitability Y1 - 2025 SN - 978-3-8007-6656-7 SP - 97 EP - 102 PB - VDE ER - TY - CHAP A1 - Hinterreiter, Marion A1 - Brückl, Oliver A1 - Rauch, Johannes ED - Technische Universität München, T1 - Challenges and Approaches for Long-Term Reactive Power Forecasting in Power Systems T2 - PESS 2025 – IEEE Power and Energy Student Summit, October 08 – 10, 2025 in Munich, Germany N2 - The transition from fossil fuels to renewable energy sources is driving profound changes across all voltage levels of the electrical grid, altering active power (P) as well as reactive power (Q) behavior. This transformation involves a shift from predominantly top-down, unidirectional electricity flows to bidirectional and increasingly complex flow patterns, fundamentally altering the operation and utilization of power systems. Many countries are already reporting notable changes in their transmission grid Q. This can lead to increased costs for grid expansion and compensation equipment, as well as grid losses. To minimize these losses and ensure grid stability and efficiency, understanding and forecasting Q long-term becomes essential. This paper addresses the challenges of long-term (1-20 years) Q forecasting in general by analyzing Q behavior in grids, the main influencing grid parameters, and reviewing existing forecasting approaches. It evaluates the applicability of these approaches and highlights current research gaps and trends. By focusing on this underexplored area, the paper aims to support the development of more advanced and reliable long-term Q forecasting techniques. KW - reactive power KW - forecasting KW - long-term KW - network models Y1 - 2025 SN - 978-3-8007-6656-7 SP - 109 EP - 114 PB - VDE Verlag ER - TY - GEN A1 - Rill, Georg A1 - Eiselt, Uwe A1 - Kelichhaus, Thomas T1 - Vehicle dynamics with RecurDyn based on the TMeasy tire model T2 - 26th International Conference on Theoretical and Applied Mechanics (ICTAM), August 25-30, 2024, Daegu, Korea Y1 - 2024 UR - https://www.researchgate.net/publication/383658881_VEHICLE_DYNAMICS_WITH_RECURDYN_BASED_ON_THE_TMEASY_TIRE_MODEL ER - TY - JOUR A1 - Tremmel, Florian A1 - Nagler, Oliver A1 - Kutter, Christoph A1 - Holmer, Rainer T1 - Double-Beam Cantilever Probe for Crack Probability Analysis of Multilayer Substrates During Wafer Probing JF - IEEE Sensors Journal N2 - During wafer testing, small probes are contacting pads on the wafer surface to check the chip functionality and identify faulty dies. To prevent damaging structures underneath, a mechanical load limit needs to be defined. This is done by intentionally overstressing the pads and searching for cracks that appear. A customized test bench with a patented sensor-indenter (SI) system is currently used to perform the contact cycles and identify crack formations in real time using the generated acoustic emissions (AEs). This method is faster and more accurate compared with previous optical detection methods. This article presents an improved version of the SI system usable in a wafer prober, featuring a double-beam cantilever beam with an exchangeable indenter tip. This leads to measurement conditions closer to productive wafer testing, enabling more accurate load limit definitions. The cantilever beam contains a strain gauge Wheatstone bridge for contact force measurement and a piezoelectric sensor element for AE signal detection. Amplifier circuits are designed for both sensors, and a data acquisition (DAQ) system is developed. A prototype of the sensor cantilever combination (SCC) is shown together with simulated and experimental results. The accuracy of the force sensor ( ±0.5 → ±1.3 mN) and the signal-to-noise ratios (SNRs) of the AE signals ( 29.1 → 21 dB) show only a small decrease compared with the previous SI system. A crack probability analysis of a test specimen confirms the usability of the SCC, as AE crack signals are detected at a similar mechanical load with both sensor setups. KW - Acoustic emission (AE) testing KW - double-beam cantilever load senso KW - fracture load limit KW - operational amplifier circuit Y1 - 2024 U6 - https://doi.org/10.1109/JSEN.2024.3486355 VL - 24 IS - 24 SP - 40295 EP - 40304 PB - IEEE ER - TY - JOUR A1 - Sterner, Michael A1 - Hofrichter, Andreas A1 - Meisinger, Alexander A1 - Bauer, Franz A1 - Pinkwart, Karsten A1 - Maletzko, Annabelle A1 - Dittmar, Felix A1 - Cremers, Carsten T1 - 19 Import options for green hydrogen and derivatives - An overview of efficiencies and technology readiness levels JF - International Journal of Hydrogen Energy N2 - The import of hydrogen and derivatives forms part of many national strategies and is fundamental to achieving climate protection targets. This paper provides an overview and technical comparison of import pathways for hydrogen and derivatives in terms of efficiency, technological maturity and development and construction times with a focus on the period up to 2030. The import of hydrogen via pipeline has the highest system efficiency at 57-67 % and the highest technological maturity with a technology readiness level (TRL) of 8-9. The import of ammonia and methanol via ship and of SNG via pipeline shows efficiencies in the range of 39-64 % and a technological maturity of TRL 7 to 9 when using point sources. Liquid hydrogen, LOHC and Fischer-Tropsch products have the lowest efficiency and TRL in comparison. The use of direct air capture (DAC) reduces efficiency and TRL considerably. Reconversion of the derivatives to hydrogen is also associated with high losses and is not achievable for all technologies on an industrial scale up to 2030. In the short to medium term, import routes for derivatives that can utilise existing infrastructures and mature technologies are the most promising for imports. In the long term, the most promising option is hydrogen via pipelines. KW - Hydrogen KW - Derivatives KW - Power-to-X KW - Efficiency KW - TRL KW - Construction time KW - Technical assessment KW - Import KW - Hydrogen strategy KW - Energy system modelling Y1 - 2024 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-77756 SN - 0360-3199 N1 - Corresponding author der OTH Regensburg: Michael Sterner VL - 90 SP - 1112 EP - 1127 PB - Elsevier ER - TY - JOUR A1 - Salama, Amgad A1 - Kou, Jisheng A1 - Dawoud, Belal A1 - Simonson, Carey T1 - A modeling approach for capillary-driven flow of a wetting fluid in a rectangular open microchannel of arbitrary axisymmetric width profile BT - Application to heat pipes JF - International Journal of Thermal Sciences N2 - Microchips are intensively used in almost all nowadays electronic devices. With the continuous advancement of our technologies, they get smaller in size than ever before. They generate high-intensity heat loads that need to be transported effectively such that they may function properly. Heat pipes have proven to be very effective in transporting relatively large heat loads from miniature components. They are of seamless structure that involves a working fluid capable of evaporation and condensation at the working temperature of the electronic chips. The working fluid is derived to move from the condenser to the evaporator via multiple microgrooves using capillary forces. It is important that the condensate reaches the evaporator at a proper rate such that no dry-out or flooding occur. In this work, we are particularly interested in the case of capillary-driven flows in rectangular microchannels. A generalized model is developed that works for axe-symmetric rectangular channels of arbitrary, moderately varying width profiles. It also accounts for any contrast of viscosity between the liquid and the vapor under isothermal conditions. The model shows to reduce to the special case of imbibition in straight and uniform microchannels, for which comparisons with experimental and modeling works show an excellent match. Cases representing linearly and quadratically varying converging/diverging width profiles have been explored. It is found that the viscosity ratio has a significant influence on the rate at which the meniscus advances. The model also negates the common practice found in the literature of using the formula developed for imbibition rates in capillary tubes for rectangular microchannels by replacing the diameter of the tube with the hydraulic diameter. It is also found that the channel profile has an influential effect on the imbibition rates. For tapered microchannels, the capillary force increases along the channel length while it decreases for diverging ones. It is interestingly demonstrated that, for quadratically tapered microchannel, the speed of the meniscus increases towards the end of the microchannel compared with linearly varying microchannels. On the other hand, for diverging microchannels, the speed of the meniscus decreases due to the increase in the cross-sectional area. Computational fluid dynamics (CFD) analysis has been conducted to provide a framework for confirmation and verification for which very good match has been established, which builds confidence in the modeling approach. KW - Microfluidics KW - Miniature devices KW - Capillary-driven flows KW - Microchannels KW - Heat pipes Y1 - 2024 U6 - https://doi.org/10.1016/j.ijthermalsci.2023.108622 SN - 1290-0729 VL - 195 PB - Elsevier 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 - Rieger, Anna A1 - van de Par, Steven A1 - Rabl, Hans-Peter A1 - Oetjen, Arne T1 - Schärfeurteile für tonhaltige Geräusche und die Konsequenzen für die instrumentelle psychoakustische Analyse T2 - Fortschritte der Akustik - DAGA 2024, 50. Jahrestagung für Akustik, 18.-21. März 2024 in Hannover N2 - In einer vorrangegangenen Studie wurde der Einfluss psychoakustischer Parameter auf Präferenzurteile für konsonante und dissonante Geräusche untersucht. Diese Geräusche hatten die gleiche Lautheit und basierten auf einem festen Rauschhintergrund und eingebetteten hochfrequenten Tonkomponenten. Es zeigte sich, dass die Präferenzurteile eines Probandenkollektives durch ebenfalls erhobene Subjektivurteile zu Schärfe, Tonhaltigkeit und Dissonanz mit hoher Präzision vorhergesagt werden konnten.Durch das angewandte Versuchsdesign konnte diese rein auf Subjektivbeurteilungen bestehende Vorhersage mit einer instrumentellen Vorhersage der Präferenzurteile verglichen werden. Der Vergleich ergab einen niedrigeren Korrelationskoeffizienten für die modellbasierte Vorhersage, was auch durch die sehr niedrige Korrelation (R2<0,2) der berechneten Schärfe nach DIN45692 mit den Schärfe-Subjektivurteilen zu begründen war. Eine mögliche Erklärung der unzureichenden Prognose der Schärfeurteile könnte in der Bewertungsstrategie der Proband:innen zu finden sein. Für die getesteten Geräusche mit auffälligen tonalen Komponenten könnte statt der Schärfe des Gesamtgeräuschs nur die Schärfe des tonalen Geräuschobjekts berücksichtigt worden sein. Die Schärfe-Analyse der auf ihren tonalen Anteil reduzierten Signale zeigt eine sehr gute Übereinstimmung mit den Subjektivurteilen, was die Hypothese einer Trennung von Ton- und Rauschobjekten unterstützt. Es wird diskutiert, ob und wie das Paradigma der akustischen Objekttrennung in der Modellierung psychoakustischer Empfindungsgrößen Anwendung finden kann. Y1 - 2024 UR - https://pub.dega-akustik.de/DAGA_2024/konferenz?article=479 SN - 978-3-939296-22-5 SP - 1210 EP - 1213 PB - Deutsche Gesellschaft für Akustik e.V. (DAGA) CY - Berlin ER - TY - JOUR 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 JF - Energies N2 - The fluctuating nature of renewable energies results in the need for sustainable storage technologies to defossilize the energy system without other negative consequences for humans and the environment. In this study, a pilot-scale trickle-bed reactor for biological methanation and various scale-up scenarios for 2024 and 2050 were investigated using life cycle assessment. A best- and worst-case scenario for technology development until 2050 was evolved using cross-consistency analysis and a 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 electrolysis operation has an especially large impact on total emissions. The final Monte Carlo simulation shows that the technology is likely to achieve a low global warming potential with a median of 104.0 kg CO2-eq/MWh CH4 and thus can contribute to decarbonization. KW - Ökobilanzierung KW - Power-to-Gas KW - Elektrolyse KW - Methanisierung KW - erneuerbare Energien Y1 - 2024 U6 - https://doi.org/https://doi.org/10.3390/en17092206 SN - 1996-1073 VL - 17 IS - 9 PB - MDPI AG CY - Basel ER - TY - RPRT A1 - Brixner, Luis A1 - Gnerlich, Patrick A1 - Jakob, Jonas A1 - Kiener, Johannes A1 - Oberländer, Jonas A1 - Plößl, Moritz A1 - Schächinger, Stefan A1 - Stelz, Raphael A1 - Wartner, Felix ED - Fuhrmann, Thomas ED - Niemetz, Michael ED - Reindl, Andrea T1 - FMS-Berichte Wintersemester 2023/24 BT - Seminar zu aktuellen Themen der Elektro- und Informationstechnik N2 - Dieser Bericht entstand ursprünglich auf Initiative der Studierenden des damals neuen Masterstudiengangs „Elektro- und Informationstechnik (MEI)“ an der OTH Regensburg, 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 ist im Laufe der Veranstaltung geeignete Literatur zu einem individuellen Thema zu recherchieren, sind Veröffentlichungen auf ihre Relevanz hin zu beurteilen und letztendlich gilt es eine eigene Ausarbeitung basierend auf der Literaturrecherche zu erstellen und diese in einem Vortrag zu präsentieren. Parallel dazu wird im Theorieteil die entsprechende Hinführung zu den verschiedenen Elementen der Wissenschaftskommunikation vermittelt: • 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 Die präsentierten Themen beruhen nicht auf eigener Forschungstätigkeit, sondern sind als einführende Reviewartikel zum jeweiligen vorgegebenen technischen oder gesellschaftspolitischen Forschungsthema zu verstehen. T3 - Forschungsmethoden-Seminar - 7 KW - Elektrotechnik KW - Informationstechnik KW - Energietechnik KW - Literaturrecherche Y1 - 2024 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-77796 IS - 1 CY - Regensburg ER - TY - RPRT A1 - Blößer, Julia A1 - Branilovic, Fabio A1 - Michael, Bretz A1 - Ebner, Andreas A1 - Gleich, Ralf A1 - Inderst, Christian A1 - Kopp, Lorenz A1 - Müller, Markus A1 - Schächiner, Michael A1 - von Beerfelde, Rebekka ED - Fuhrmann, Thomas ED - Niemetz, Michael ED - Reindl, Andrea T1 - FMS-Berichte Sommersemester 2024 BT - Seminar zu aktuellen Themen der Elektro- und Informationstechnik T2 - FMS-Berichte Sommersemester 2024 N2 - Dieser Bericht entstand ursprünglich auf Initiative der Studierenden des damals neuen Masterstudiengangs „Elektro- und Informationstechnik (MEI)“ an der OTH Regensburg, 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 ist im Laufe der Veranstaltung geeignete Literatur zu einem individuellen Thema zu recherchieren, sind Veröffentlichungen auf ihre Relevanz hin zu beurteilen und letztendlich gilt es eine eigene Ausarbeitung basierend auf der Literaturrecherche zu erstellen und diese in einem Vortrag zu präsentieren. Parallel dazu wird im Theorieteil die entsprechende Hinführung zu den verschiedenen Elementen der Wissenschaftskommunikation vermittelt: • 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 Die präsentierten Themen beruhen nicht auf eigener Forschungstätigkeit, sondern sind als einführende Reviewartikel zum jeweiligen vorgegebenen technischen oder gesellschaftspolitischen Forschungsthema zu verstehen. T3 - Forschungsmethoden-Seminar - 8 KW - Elektrotechnik KW - Informationstechnik KW - Energietechnik KW - Literaturrecherche Y1 - 2024 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-77801 IS - 1 CY - Regensburg 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 N1 - Der Aufsatz wurde peer-reviewed veröffentlicht und ist ebenfalls in diesem Repositorium verzeichnet unter: https://opus4.kobv.de/opus4-oth-regensburg/8485 PB - Research Square Platform LLC ER - TY - JOUR A1 - Tremmel, Florian A1 - Nagler, Oliver A1 - Kutter, Christoph A1 - Holmer, Rainer T1 - Mechanical robustness analysis of semiconductors with a single needle probe card using acoustic emissions JF - e-Journal of Nondestructive Testing N2 - The combination of indentation testing and acoustic emission (AE) is widely used to analyze the fracture toughness of test substrates. In the manufacturing of semiconductor devices this material parameter also plays an important role. During the so-called wafer testing inside a wafer prober small probe tips are pressed onto the chip surface to check its performance. To prevent damaging the chip by that, the fracture toughness and load limit of it has to be defined in a prequalification step. This paper presents a test system that imitates the wafer testing process as close as possible and uses acoustic emission to detect appearing cracks and thereby also the load limit. The frontend of the test setup consists of a modular single needle probe card which can be placed in a wafer prober. Also, the indenter properties (tip diameter, stiffness, etc.) can be adjusted to the probe used later on during productive wafer testing to ensure realistic probing conditions. A piezoelectric sensor and a full strain gauge Wheatstone bridge are implemented close to the single indenter to measure the AEs and the applied contact force respectively. The signal-to-noise-ratios (SNRs) of both sensors are improved with an own analog amplifier module before recording them with an USB oscilloscope. A developed measurement software (LabVIEW) is used to adjust measurement parameters (trigger limit, record length, conversion factors, etc.) and automatically store and separate measurement data from different acoustic events and imprints. To evaluate the result files a second software tool (MATLAB) reads the files out and clusters the recorded events to separate crack signals from electrical and mechanical disturbances. With a prototype first test results are generated and the functionality and accuracy of the measurement concept is proven. KW - Acoustic Emission KW - Crack probability distribution KW - Fracture load limit KW - Wafer testing Y1 - 2024 U6 - https://doi.org/10.58286/30254 SN - 1435-4934 VL - 29 IS - 10 PB - NDT.net 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 - RPRT A1 - Andratschke, Christin A1 - Ceullo, Laura A1 - Dawoud, Belal A1 - Draeger, Susan A1 - Gerdes, Thorsten A1 - Giebisch, Matthias A1 - Grießhammer, Peter A1 - Haas, Katharina A1 - Haug, Sonja A1 - Helling, Dominik A1 - Kominis, Lena A1 - Lang, Christian A1 - Malz, Sebastian A1 - Melzl, Johannes A1 - Michlbauer, David A1 - Mühlberger, Thomas A1 - Nagl, Klaus A1 - Preis, Michael A1 - Rechenauer, Christian A1 - Riederer, Michael A1 - Rückerl, Alexander A1 - Saller, Tobias A1 - Schnabl, Andreas A1 - Stadler, Michael A1 - Steffens, Oliver A1 - Steininger, Peter A1 - Stelzl, André A1 - Toutouly, Lovis A1 - Trauner, Matthias A1 - Vetter, Miriam A1 - Walbrunn, Johannes A1 - Weber, Karsten A1 - Zielbauer, Lukas ED - Steffens, Oliver T1 - MAGGIE: Energetische Modernisierung des genossenschaftlichen Wohnquartiers Margaretenau in Regensburg BT - Musterlösungen für solaroptimiertes Wohnen mit innovativen solaraktiven Baustoffen und einem KI-gestützten Energiemanagement für eine netzdienliche, emissionsarme Strom- und Wärmelogistik; Ergebnisbericht N2 - Im Projekt MAGGIE wurden für das genossenschaftliche historische Stadtquartier „Margaretenau“ in Regensburg Musterlösungen für energieoptimiertes Wohnen mit innovativen Wandaufbauten aus solaraktiven Baukonstruktionen und einer vorhersagebasierten Versorgungstechnologie erforscht. Dazu wurde ein bestehendes Wohngebäude als Demonstrations- und Versuchsobjekt mit einem neuartigen, besonders effizienten Hybridsystem aus Wärmepumpentechnologie und Kraft- Wärme-Kopplung ausgestattet und untersucht, ergänzt durch eine dynamische Wärmelogistik zur Verringerung von Verteilungsverlusten. Das System wurde durch ein neu entwickeltes, allgemein einsetzbares Planungs-, Optimierungs- und Steuerungstool ausgelegt und im Betrieb geregelt. Die in Echtzeit laufende Nachoptimierung des Systems während des Betriebs greift dabei auf reale Monitoringdaten zu. Die Einbindung von Nutzerbedarfsprofilen, Strombörse und Wetterdaten in die Steuerung gestattet einen dynamischen und perspektivischen Anlagenbetrieb zur Maximierung der Solar- und Umweltwärme-Anteile der Energieversorgung und leistet damit einen wirksamen Beitrag zu einem emissionsarmen, klimafreundlichen Gebäudebetrieb. Für die denkmalgerechte Modernisierung der historischen Fassaden wurde ein solaraktives und solaradaptives Außenputzsystem entwickelt und in der Realität getestet. Am Bestandsgebäude kam anstelle eines Wärmedämmverbundsystems ein innovativer Dämmputz mit Mikrohohlglaskugeln zum Einsatz. Die Skalierbarkeit erlaubt eine abschnittsweise Modernisierung des gesamten Ensembles über mehrere Jahre. Durch die hohe Energieeffizienz wird die Warmmiete für die Bewohner der genossenschaftlichen Siedlung durch die Modernisierungsmaßnahmen nicht erhöht, so dass auch nach der Modernisierung ein bezahlbares Wohnen sichergestellt wird. KW - Altbaumodernisierung KW - Energieeinsparung KW - Energiebewusstes Bauen KW - Haus Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-53354 SN - 978-3-96256-100-0 N1 - Gefördert durch einen Beschluss des Bundestages durch das Bundesministerium für Wirtschaft und Klimaschutz (BMWK); Projektlaufzeit Oktober 2017 bis Juni 2022; Förderkennzeichen 03SBE0007A–E N1 - korrigierte Version unter: https://doi.org/10.35096/othr/pub-5901 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. T3 - Forschungsmethoden-Seminar - 5 KW - Elektrotechnik KW - Informationstechnik KW - Angewandte Wissenschaften KW - Literaturrecherche Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-60324 CY - Regensburg ER - TY - RPRT A1 - Andratschke, Christin A1 - Ceullo, Laura A1 - Dawoud, Belal A1 - Draeger, Susan A1 - Gerdes, Thorsten A1 - Giebisch, Matthias A1 - Grießhammer, Peter A1 - Haas, Katharina A1 - Haug, Sonja A1 - Helling, Dominik A1 - Kominis, Lena A1 - Lang, Christian A1 - Malz, Sebastian A1 - Melzl, Johannes A1 - Michlbauer, David A1 - Mühlberger, Thomas A1 - Nagl, Klaus A1 - Preis, Michael A1 - Rechenauer, Christian A1 - Riederer, Michael A1 - Rückerl, Alexander A1 - Saller, Tobias A1 - Schnabl, Andreas A1 - Stadler, Michael A1 - Steffens, Oliver A1 - Steininger, Peter A1 - Stelzl, André A1 - Toutouly, Lovis A1 - Trauner, Matthias A1 - Vetter, Miriam A1 - Walbrunn, Johannes A1 - Weber, Karsten A1 - Zielbauer, Lukas ED - Steffens, Oliver T1 - MAGGIE: Energetische Modernisierung des genossenschaftlichen Wohnquartiers Margaretenau in Regensburg BT - Musterlösungen für solaroptimiertes Wohnen mit innovativen solaraktiven Baustoffen und einem KI-gestützten Energiemanagement für eine netzdienliche, emissionsarme Strom- und Wärmelogistik; Ergebnisbericht N2 - Im Projekt MAGGIE wurden für das genossenschaftliche historische Stadtquartier „Margaretenau“ in Regensburg Musterlösungen für energieoptimiertes Wohnen mit innovativen Wandaufbauten aus solaraktiven Baukonstruktionen und einer vorhersagebasierten Versorgungstechnologie erforscht. Dazu wurde ein bestehendes Wohngebäude als Demonstrations- und Versuchsobjekt mit einem neuartigen, besonders effizienten Hybridsystem aus Wärmepumpentechnologie und Kraft- Wärme-Kopplung ausgestattet und untersucht, ergänzt durch eine dynamische Wärmelogistik zur Verringerung von Verteilungsverlusten. Das System wurde durch ein neu entwickeltes, allgemein einsetzbares Planungs-, Optimierungs- und Steuerungstool ausgelegt und im Betrieb geregelt. Die in Echtzeit laufende Nachoptimierung des Systems während des Betriebs greift dabei auf reale Monitoringdaten zu. Die Einbindung von Nutzerbedarfsprofilen, Strombörse und Wetterdaten in die Steuerung gestattet einen dynamischen und perspektivischen Anlagenbetrieb zur Maximierung der Solar- und Umweltwärme-Anteile der Energieversorgung und leistet damit einen wirksamen Beitrag zu einem emissionsarmen, klimafreundlichen Gebäudebetrieb. Für die denkmalgerechte Modernisierung der historischen Fassaden wurde ein solaraktives und solaradaptives Außenputzsystem entwickelt und in der Realität getestet. Am Bestandsgebäude kam anstelle eines Wärmedämmverbundsystems ein innovativer Dämmputz mit Mikrohohlglaskugeln zum Einsatz. Die Skalierbarkeit erlaubt eine abschnittsweise Modernisierung des gesamten Ensembles über mehrere Jahre. Durch die hohe Energieeffizienz wird die Warmmiete für die Bewohner der genossenschaftlichen Siedlung durch die Modernisierungsmaßnahmen nicht erhöht, so dass auch nach der Modernisierung ein bezahlbares Wohnen sichergestellt wird. KW - Altbaumodernisierung KW - Energieeinsparung KW - Energiebewusstes Bauen KW - Haus Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-59011 SN - 978-3-96256-100-0 N1 - Gefördert durch einen Beschluss des Bundestages durch das Bundesministerium für Wirtschaft und Klimaschutz (BMWK); Projektlaufzeit Oktober 2017 bis Juni 2022; Förderkennzeichen 03SBE0007A–E CY - Regensburg 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 - 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 - Huber, Lea A1 - Heindl, Melanie A1 - Schlosser, Marc A1 - Pfitzner, Arno A1 - Dawoud, Belal T1 - On the Cycle Stability and Macroscopic Structure of Iron Oxide Pellets for Thermochemical Hydrogen Storage: Influence of Water Content during the Pelletizing Process JF - Applied Sciences N2 - Hydrogen storage based on the repeated reduction and oxidation (redox) reactions of iron oxide/iron composites represents a promising technology. This work is dedicated to studying the influence of the amount of water added during the pelletizing process on the cycle stability and structure of iron oxide pellets. The storage composites were prepared from iron oxide (Fe2O3) and 10 wt.-% support material (cement) with different amounts of water (18 and 33 wt.-%) in a laboratory-scale pelletizing disk. To evaluate the cycle stability of the composites, the kinetics of the redox reactions were experimentally measured at 800 ∘ C in an atmosphere of 50% N2 and 50% H2 (reduction) or 50% steam (oxidation), respectively. Moreover, the structure of the pellets was analyzed by micro-computed tomography scans. It turned out that pellets with higher water contents attained faster kinetics and a higher cycle stability. The sample with the least water content (18 wt.-%) needed about 26 min and 19 min to reach a conversion rate of 80% during the reduction and oxidation reactions of the sixth redox cycle, respectively. In contrast, the sample with the highest water content (33 wt.-%) could achieve the same conversion rate after 18 min (reduction) and 13 min (oxidation) during the ninth redox cycle. KW - hydrogen storage KW - redox reactions KW - iron/iron oxide KW - pelletizing process KW - cycle stability KW - water content Y1 - 2023 U6 - https://doi.org/10.3390/app13116408 N1 - Corresponding author: Belal Dawoud VL - 13 IS - 11 PB - MDPI CY - 16 ER - TY - JOUR A1 - Mikhaeil, Makram A1 - Gaderer, Matthias A1 - Dawoud, Belal T1 - On the application of adsorber plate heat exchangers in thermally driven chillers BT - An experimental and analytical study JF - Applied Thermal Engineering N2 - The effect of both heat and mass transfer characteristic lengths (HTCL, MTCL) of two different adsorber plate heat exchangers (APHE), for application in an adsorption chiller, on the adsorption and desorption kinetics is investigated. Three representative test frames (TF1-TF3) are prepared to examine small-scale adsorbent samples of the microporous silica gel (Siogel of Oker-Chemie, Germany) applying the volumetric large-temperature-jump methodology at different operating conditions. Based on the obtained kinetic data, an analytical model has been developed to predict the specific cooling power (SCP) and the coefficient of performance (COP) of a single-bed adsorption chiller comprising the studied APHEs. It turned out that, within the tested range of HTCL and MTCL, it can be concluded that, the adsorption kinetics are mainly influenced by the MTCL, while the desorption kinetics are dominated by the HTCL of the adsorbent domain. Applying Siogel as loose pellets inside a newly introduced APHE results in of 423.3 and 182.7 W⋅kg−1, at the evaporator temperatures of 15 °C and 5 °C, respectively. Herein, the condenser and adsorber-end temperatures amount to 30 °C and the desorption-end temperature to 90 °C. The corresponding s amount to 0.50 and 0.40, respectively, which represent quite promising results for further design optimizations. Y1 - 2023 U6 - https://doi.org/10.1016/j.applthermaleng.2022.119713 VL - 220 PB - Elsevier ER - TY - RPRT A1 - Zacherl, Florian A1 - Wopper, Christoph A1 - Mieslinger, Johann A1 - Peis, Michael A1 - Rabl, Hans-Peter T1 - Schlussbericht zum Verbundvorhaben NAMOSYN: Nachhaltige Mobilität durch synthetische Kraftstoffe BT - Cluster FC1A: OME Für Dieselmotoren - Motorische Testung; Cluster FC2: C1-O Systeme für Ottomotoren N2 - Im Labor für Verbrennungsmotoren und Abgasnachbehandlung der OTH-Regensburg sollten im Zuge des NAMOSYN-Projektes zwei Vertreter klimaneutraler Kraftstoffe an verschiedenen Systemprüfständen (Motor-, Einspritzprüfstand, optisch zugängliche Einspritzkammer, …) und mit Hilfe von Simulationsmethoden für den Einsatz in bestehenden Verbrennungsmotoren untersucht werden. Synthetische Kraftstoffe aus der Gruppe der Oxymethylenether (OME) stellen eine CO2-neutrale Alternative zu fossilem Dieselkraftstoff dar. Für Ottomotoren wurde untersucht, ob der synthetische Kraftstoff DMC/MeFo (Dimethylcarbonat & Methylformiat) einen Ersatz für Ottokraftstoff darstellen kann, bzw. eine Drop-In-Fähigkeit gegeben ist. Die OTH Regensburg bearbeitete 2 unabhängige Teilvorhaben zur motorischen Testung von synthetischen Kraftstoffen: „FC 1A: Motorische Testung von OME“ und „FC 2: Untersuchung von C1-Oxygenaten für Ottomotoren“. Die Projektlaufzeit betrug 3,5 Jahre, inkl. kostenneutraler Verlängerung um 6 Monate aufgrund der Corona-Pandemie. Im FC1A "AP2-Nachrüstung Dieselmotoren" der OTH Regensburg lag der Fokus auf der Erforschung der Potentiale und der Umrüstung eines Einzylinder-Dieselmotors mit Pumpe-Leitung-Düse-(PLD)-Einspritzsystem des Projektpartners Motorenfabrik Hatz GmbH und Co. KG für OME-Betrieb. Im AP2.1 wurden umfangreiche Daten gesammelt und Simulationsmodelle des Motors und PLD-Einspritzsystems erstellt und mit Dieselkraftstoff und OME validiert. Nachfolgend wurden Parameterstudien zur Geometrie des Einspritzsystems und der physikalischen Eigenschaften von OME durchgeführt. In AP2.2 und AP2.3 wurden umfangreiche Untersuchungen an einem Motor- und Einspritzsystemprüfstand mit Diesel und OME durchgeführt und der Steuergerätedatensatz für den OME-Betrieb optimiert. Die Ergebnisse zeigen, dass die Umstellung des Kraftstoffs auf OME, insbesondere bei einfachen Motoren mit rudimentärer Einspritztechnik und ohne Mittel zur NOx-Reduzierung (keine AGR oder SCR), ein enormes Potenzial zur Steigerung des Wirkungsgrads bei gleichzeitiger Reduzierung aller regulierten Schadstoffe (NOx, 𝑃N, 𝑃M, CO und 𝑉OC) eröffnet. Die Ergebnisse und generierten Simulationsmodelle unterstützen eine schnelle Serienentwicklung und Einführung von OME-Umrüstlösungen. In FC 2 werden die vielversprechenden Kraftstoffe Methylformiat (MeFo) und Dimethylcarbonat (DMC) motorisch getestet. Untersuchungen am Kraftstoffsystem und wichtigen Komponenten dienen als Grundlage für das AP3. Im AP3 wird die Machbarkeit der DMC/MeFo-Verbrennung am Vollmotor demonstriert und die erwarteten Emissionsvorteile gegenüber herkömmlichen Ottokraftstoffen gezeigt. Abweichend von der ursprünglichen Planung werden an der OTH Regensburg Kraftstoffblends aus Benzin und MeFo untersucht, um den Einsatzbereich des Kraftstoffs zu erweitern. In AP5 werden potentielle Mischungsverhältnisse analysiert und die Eigenschaften der ausgewählten Kraftstoffmischungen an einem Einspritzratenprüfstand, an der Einspritzkammer und am Vollmotor untersucht. Es werden Einspritzverhalten, Gemischaufbereitung und Abgasemissionen bewertet. Zudem wird eine Kraftstoffmischanlage entwickelt und ein optischer Zugang am Vollmotor ermöglicht. Eine Ölverdünnungsmesstechnik wird eingesetzt, um den Kraftstoffeintrag ins Motoröl zu untersuchen KW - Synthetische Kraftstoffe KW - OME KW - DMC KW - MeFo KW - E-Fuels Y1 - 2023 CY - Regensburg ER - TY - CHAP A1 - Rill, Georg ED - Fleury, Agenor de T. T1 - Real-Time capable Multibody Model of dual Truck Front Axles T2 - Proceedings of DINAME 2023 - Selected Papers of the XIX International Symposium on Dynamic Problems of Mechanics, 26 Feb - 03 Mar 2023, Pirenópolis, Brazil N2 - Dual front steering axles are quite common in multi-axled heavy duty trucks. In standard layouts of such axle combinations, the steer motions of the wheels depend not only on the rotation of the steering wheel but also on the movements of the axles. As a consequence, the model complexity of the steering system should match with the complexity of the suspension model. The development of new technologies like advanced driver assistance systems or autonomous driving can only be accomplished efficiently using extensive simulation methods. Such kind of applications demand for computationally efficient vehicle models. This paper presents a steering system model for dual front axles of heavy duty trucks which supplements the suspension model of the axles. The model takes the torsional compliance of the steering column as well as the stiffness of the tie rods and the coupling rod into account. A quasi-static solution provides a straight forward computation including the partial derivatives required for an efficient implicit solver. The steering system model matches perfectly with comparatively lean, but sufficiently accurate multibody suspension models. KW - Steering System KW - Dual Axles KW - Multibody Model KW - Vehicle Dynamics KW - Real-Time Y1 - 2023 UR - https://www.researchgate.net/publication/369256274_Real-Time_capable_Multibody_Model_of_dual_Truck_Front_Axles PB - Springer 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 - JOUR A1 - Keiner, Dominik A1 - Thoma, Christian A1 - Bogdanov, Dmitrii A1 - Breyer, Christian T1 - Seasonal hydrogen storage for residential on- and off-grid solar photovoltaics prosumer applications: Revolutionary solution or niche market for the energy transition until 2050? JF - Applied Energy N2 - Appropriate climate change mitigation requires solutions for all actors of the energy system. The residential sector is a major part of the energy system and solutions for the implementation of a seasonal hydrogen storage system in residential houses has been increasingly discussed. A global analysis of prosumer systems including seasonal hydrogen storage with water electrolyser, hydrogen compressor, storage tank, and a fuel cell studying the role of such a seasonal household storage in the upcoming decades is not available. This study aims to close this research gap via the improved LUT-PROSUME model, which models a fully micro sector coupled residential photovoltaic prosumer system with linear optimisation for 145 regions globally. The modelling of the cost development of hydrogen storage components allows for the simulation of a residential system from 2020 until 2050 in 5-year steps in hourly resolution. The systems are cost-optimised for either on- or off-grid operation in eight scenarios including battery electric vehicles, which can act as an additional vehicle-to-home electricity storage for the system. Results show that implementation of seasonal hydrogen systems only occurs in least cost solutions in high latitude countries when the system is forced to run in off-grid mode. In general, a solar photovoltaic plus battery system including technologies that can cover the heat demand is the most economic choice and can even achieve lower cost than a full grid supply in off-grid operation for most regions until 2050. Additional parameters including the self-consumption ratio, the demand cover ratio, and the heat cover ratio can therefore not be improved by seasonal storage systems if economics is the main deciding factor for a respective system. Further research opportunities and possible limitations of the system are then identified. KW - Battery KW - Electrolyser KW - Fuel Cell KW - Hydrogen KW - ProsumerIridium KW - Residential seasonal storage KW - Rooftop solar photovoltaics Y1 - 2023 U6 - https://doi.org/10.1016/j.apenergy.2023.121009 VL - 340 PB - Elsevier ER - TY - JOUR A1 - Walter, Stefanie A1 - Schwanzer, Peter A1 - Hagen, Gunter A1 - Rabl, Hans-Peter A1 - Dietrich, Markus A1 - Moos, Ralf T1 - Soot Monitoring of Gasoline Particulate Filters Using a Radio-Frequency-Based Sensor JF - Sensors N2 - Owing to increasingly stringent emission limits, particulate filters have become mandatory for gasoline-engine vehicles. Monitoring their soot loading is necessary for error-free operation. The state-of-the-art differential pressure sensors suffer from inaccuracies due to small amounts of stored soot combined with exhaust gas conditions that lead to partial regeneration. As an alternative approach, radio-frequency-based (RF) sensors can accurately measure the soot loading, even under these conditions, by detecting soot through its dielectric properties. However, they face a different challenge as their sensitivity may depend on the engine operation conditions during soot formation. In this article, this influence is evaluated in more detail. Various soot samples were generated on an engine test bench. Their dielectric properties were measured using the microwave cavity perturbation (MCP) method and compared with the corresponding sensitivity of the RF sensor determined on a lab test bench. Both showed similar behavior. The values for the soot samples themselves, however, differed significantly from each other. A way to correct for this cross-sensitivity was found in the influence of exhaust gas humidity on the RF sensor, which can be correlated with the engine load. By evaluating this influence during significant humidity changes, such as fuel cuts, it could be used to correct the influence of the engineon the RF sensor. KW - dielectric properties KW - engine test bench KW - gasoline particulate filter (GPF) KW - microwave cavity perturbation KW - radio-frequency (RF) KW - soot mass determination Y1 - 2023 U6 - https://doi.org/10.3390/s23187861 SN - 1424-8220 N1 - This research work was funded by the Bavarian Research Foundation (Bayerische Forschungsstiftung, BFS) as part of the project “Load Sensor for GPF” (AZ-1288-17). VL - 23 IS - 18 SP - 1 EP - 19 PB - MDPI 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 - 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 - JOUR A1 - Gamisch, Bernd A1 - Ettengruber, Stefan A1 - Gaderer, Matthias A1 - Dawoud, Belal T1 - Dynamic simulation of isothermal and non-isothermal reduction and oxidation reactions of iron oxide for a hydrogen storage process JF - Renewable and Sustainable Energy N2 - This work aims first to develop a dynamic lumped model for the isothermal reactions of hydrogen/steam with a single iron oxide/iron pellet inside a tubular reactor and to validate the model results against the experimental reaction kinetic data with the help of our STA device. To describe the temporal change in mass, and consequently, the temporal heat of reaction, the shrinking core model, based on the geometrical contracting sphere, is applied. It turned out that, the simulation model can reproduce the experimental, temporal concentration and temperature-dependent conversion rates with a maximum deviation of 4.6% during the oxidation reactions and 3.1% during the reduction reactions. In addition, a measured isothermal storage process comprising one reduction and one oxidation phase with a holding phase in between on a single reacting pellet could be reproduced with a maximum absolute deviation in the conversion rate of 1.5%. Moreover, a lumped, non-isothermal simulation model for a pelletized tubular redox-reactor including 2kg of iron oxide pellets has been established, in which the heat of reaction, heat transfer to the ambient and heat transfer between the solid and gas phases are considered. The temporal courses of the outlet gas concentration as well as the temperatures of the gas stream and the solid material at a constant input gas flow rate and a constant reacting gas inlet concentration but different input gas temperatures are estimated. Because of the endothermic nature of the reduction reaction, the inlet reacting gas temperature shall be kept high to prevent the severe temperature drop in the solid phase and, consequently, the significant reduction of the reaction rate. Contrary to that, the oxidation process requires lower input gas temperatures to avoid the excessive overheating of the reaction mass and, consequently, the sintering of the reacting pellets. Finally, five of the previous reactors have been connected in series to explore the influence of the changing inlet gas temperatures and concentrations on the dynamic performance of each storage mass. KW - hydrogen storage KW - iron/iron oxide KW - redox reactions KW - lumped model KW - isothermal reactions KW - non-isothermal reactions KW - kinetics of reactions KW - Aspen Custom Modeler Y1 - 2023 U6 - https://doi.org/10.55092/rse20230004 N1 - Corresponding author: Belal Dawoud VL - 1 IS - 1 PB - ELSP, International Open Science Platform ER - TY - INPR A1 - Takayasu, Anna A1 - Weikl, Simone A1 - Dahmen, Victoria A1 - Bogenberger, Klaus T1 - Impact of Travel Stress and Infrastructure Quality on Cycling Mode Share: Insights From Multimodal Trajectory and Survey Data Analysis N2 - This study explores the relationship between travel stress, infrastructure quality, and cycling mode share. Utilizing multimodal trajectory data, survey responses on travel stress, and detailed road network information with geological and bicycle facility data, the study analyzes correlations between actual and perceived infrastructure quality, travel stress, and cycling mode share, as well as the impact of travel time and distance on cycling mode share. The results indicate significant correlations between perceived infrastructure quality and travel stress levels, and between travel stress levels and cycling mode share, particularly among regular bike users. However, clear correlations between actual and perceived infrastructure quality, and between perceived infrastructure quality and cycling mode share, were not observed. Additionally, direct effects of travel time and distance on cycling mode share were not evident. From these findings, three main insights emerge. Firstly, accurately estimating cycling mode share requires considering multiple parameters beyond travel time and distance. Secondly, to implement effective measures for bicycle facilities, a detailed analysis of perceived infrastructure quality, incorporating actual infrastructure design, is crucial. Lastly, travel stress, when carefully assessed with consideration of various factors beyond infrastructure design, emerges as a key determinant of travel mode choice. These insights have significant implications for future cycling research, including the development of travel mode choice models and estimating cycling demand. The study's valuable contributions advance efforts to promote cycling as a sustainable and preferred mode of transportation. Y1 - 2023 U6 - https://doi.org/10.13140/RG.2.2.30696.85766 PB - Researchgate 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 - JOUR A1 - Mikhaeil, Makram A1 - Nowak, Sebastian A1 - Palomba, Valeria A1 - Frazzica, Andrea A1 - Gaderer, Matthias A1 - Dawoud, Belal T1 - Experimental and analytical investigation of applying an asymmetric plate heat exchanger as an evaporator in a thermally driven adsorption appliance JF - Applied Thermal Engineering N2 - This communication presents an experimental and analytical study on the evaporation mechanism in a closed-structured asymmetric plate heat exchanger (PHE) employed as a stagnant water evaporator for the application in an adsorption heat transformation appliance. To this aim, an experimental unit is constructed, which comprises two identical PHEs, one acting as an vaporator/condenser and the second, as an adsorber/desorber. Two endoscopes are mounted inside the investigated evaporator to visualize the evaporation mechanism when performing adsorption-evaporation processes under different boundary conditions. It turned out that the evaporation mechanism is a partially covered, thin film evaporation. A heat transfer analysis is performed to evaluate the heat transfer coefficient of the thin film evaporation () inside the investigated evaporator, resulting in -values between 1330 and 160 [W∙m−2∙K−1] over the investigated adsorption-evaporation time. Correlating the obtained () to the film thickness and the wetted area results in -values between 0.34 and 0.78 [mm] and wetted to total area ratios of 0.78 to 0.16. Besides, an analytical model has been developed and introduced to correlate the overall evaporator heat transfer coefficient with the adsorption potential and the time rate of change of the water uptake. KW - Adsorption-evaporation KW - Evaporator KW - Plate heat exchanger KW - Thin film evaporation Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-61115 N1 - Corresponding author: Belal Dawoud IS - 228 PB - Elsevier 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 - 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 - RPRT A1 - Caspar, Stefan A1 - Dorfner, Manuel A1 - Engelmann, Uwe A1 - Erhardsberger, Ludwig A1 - Gressitzek, Tobias A1 - Michelmann, Björn A1 - Steinberger, Melanie A1 - Stuchlý, Jan ED - Meier, Hans ED - Niemetz, Michael ED - Fuhrmann, Thomas ED - Reindl, Andrea T1 - FMS-Berichte Sommersemester 2023 BT - Seminar zu aktuellen Themen der Elektro- und Informationstechnik N2 - Dieser Bericht entstand ursprünglich auf Initiative der Studierenden des damals neuen Masterstudiengangs „Elektro- und Informationstechnik (MEI)“ an der OTH Regensburg, 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 ist im Laufe der Veranstaltung geeignete Literatur zu einem individuellen Thema zu recherchieren, sind Veröffentlichungen auf ihre Relevanz hin zu beurteilen und letztendlich gilt es eine eigene Ausarbeitung basierend auf der Literaturrecherche zu erstellen und diese in einem Vortrag zu präsentieren. Parallel dazu wird im Theorieteil die entsprechende Hinführung zu den verschiedenen Elementen der Wissenschaftskommunikation vermittelt: • 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 Die präsentierten Themen beruhen nicht auf eigener Forschungstätigkeit, sondern sind als einführende Reviewartikel zum jeweiligen vorgegebenen technischen oder gesellschaftspolitischen Forschungsthema zu verstehen. T3 - Forschungsmethoden-Seminar - 6 KW - Elektrotechnik KW - Informationstechnik KW - Energietechnik KW - Literaturrecherche Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-77787 IS - 1 CY - Regensburg 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 - 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 -