• Membrane Interlayer with Pt Recombination Particles for Reduction of the Anodic Hydrogen Content in PEM Water Electrolysis 

  Klose, C.; Trinke, P.; Boehm, T.; Bensmann, B.; Vierrath, S.; Hanke-Rauschenbach, R.; Thiele, S. (Pennington, New Jersey : Electrochemical Society (ECS), 2018)

  Polymer electrolyte membrane (PEM) water electrolysis is a key technology for sustainable hydrogen based energy supply. Gas permeation through the PEM leads to hydrogen in oxygen at the anode side posing a safety hazard ...
• Local Current Density and Electrochemical Impedance Measurements within 50 cm Single-Channel PEM Electrolysis Cell 

  Immerz, C.; Bensmann, B.; Trinke, P.; Suermann, M.; Hanke-Rauschenbach, R. (Pennington : Electrochemical Society (ECS), 2018)

  The present analysis shows the local distribution of current density and EIS measurements along a 50 cm single-channel proton exchange membrane water electrolysis (PEMWE) cell. Measurements for operating modes with one ...
• Challenges and Opportunities of Very Light High-Performance Electric Drives for Aviation 

  Henke, Markus; Narjes, Gerrit; Hoffmann, Jan; Wohlers, Constantin; Urbanek, Stefan; Heister, Christian; Steinbrink, Joern; Canders, Wolf-Ruediger; Ponick, Bernd (Basel : MDPI, 2018)

  The demand for alternative fueling methods to reduce the need for fossil fuels is not limited to the electrification of ground vehicles. More-electric and all-electric aircraft pose challenges, with extensive requirements ...
• Mesh-based piecewise planar motion compensation and optical flow clustering for ROI coding 

  Meuel, Holger; Munderloh, Marco; Reso, Matthias; Ostermann, Joern (Cambridge : Cambridge University Press, 2015)

  For the transmission of aerial surveillance videos taken from unmanned aerial vehicles (UAVs), region of interest (ROI)-based coding systems are of growing interest in order to cope with the limited channel capacities ...
• Quasi-two-level PWM operation of modular multilevel converters : implementation, analysis, and application to medium-voltage drives 

  Kucka, Jakub (Hannover : Institutionelles Repositorium der Leibniz Universität Hannover, 2019)

  The low-frequency operation of modular multilevel converters, required by variable-speed drives, is generally challenging within the established operation modes. Especially when rated torque beginning from zero speed is ...
• Beiträge zu fehlertoleranten Fahrzeugantrieben mit Radnabenmotoren ohne Reibungsbremse 

  Krone, Tobias (Hannover : Institutionelles Repositorium der Leibniz Universität Hannover, 2019)

  Diese Arbeit beschäftigt sich mit fehlertoleranten Radnabenantrieben mit integrierter Leistungselektronik für Elektrofahrzeuge. Die Besonderheit des betrachteten Fahrzeugtyps ist, dass die Bremsfunktion an den angetriebenen ...
• Modellierung und Regelung von fünfphasigen Synchronmaschinen unter Berücksichtigung von Sättigungseffekten und Mehrfachanisotropien 

  Jonsky, Torben (Hannover : Institutionelles Repositorium der Leibniz Universität Hannover, 2019)

  Die Verwendung von elektrischen Maschinen mit einer Phasenzahl größer als drei bringt zahlreiche Vorteile mit sich, wie beispielsweise die Erhöhung der Systemleistungsdichte durch Nutzung der dritten Harmonischen und ...
• CPES Testing with mosaik: Co-Simulation Planning, Execution and Analysis 

  Steinbrink, Cornelius; Blank-Babazadeh, Marita; El-Ama, André; Holly, Stefanie; Bengt, Lüers; Nebel-Wenner, Marvin; Ramírez Acosta, Rebeca P.; Raub, Thomas; Schwarz, Jan Sören; Stark, Sanja; Astrid, Nieße; Lehnhoff, Sebastian (Basel : MDPI, 2019)

  The complex nature of cyber-physical energy systems (CPES) makes systematic testing of new technologies for these setups challenging. Co-simulation has been identified as an efficient and flexible test approach that allows ...
• Exploring the Causes of Power-Converter Failure in Wind Turbines based on Comprehensive Field-Data and Damage Analysis 

  Fischer, Katharina; Pelka, Karoline; Puls, Sebastian; Poech, Max-Hermann; Mertens, Axel; Bartschat, Arne; Tegtmeier, Bernd; Broer, Christian; Wenske, Jan (Basel : MDPI, 2019)

  Power converters are among the most frequently failing components of wind turbines. Despite their massive economic impact, the actual causes and mechanisms underlying these failures have remained in the dark for many years. ...
• Frequency-domain modeling of harmonic interactions in pulse-width modulated voltage-source inverter drives 

  John, Malte (Hannover : Institutionelles Repositorium der Leibniz Universität Hannover, 2019)

  The method presented in this thesis allows for the calculation of the current and voltage spectra of a drive system for the steady state, while considering the influence of interactions between the system components. The ...
• Representation and contextualization for document understanding 

  Tran, Nam Khanh (Hannover : Institutionelles Repositorium der Leibniz Universität Hannover, 2019)

  Document understanding requires discovery of meaningful patterns in text, which in turn involves analyzing documents and extracting useful information for a certain purpose. There is a multitude of problems that need to ...
• Concepts and tools for the effective and efficient use of web archives 

  Holzmann, Helge (Hannover : Institutionelles Repositorium der Leibniz Universität Hannover, 2019)

  Web archives constitute valuable sources for researchers in various disciplines. However, their sheer size, the typically broad scope and their temporal dimension make them difficult to work with. We have identified three ...
• Fast pulsed operation of a small non-radioactive electron source with continuous emission current control 

  Cochems, Philipp; Kirk, Ansgar T.; Bunert, Erik; Runge, M.; Goncalves, P.; Zimmermann, Stefan (College Park, MA : American Institute of Physics (AIP), 2015)

  Non-radioactive electron sources are of great interest in any application requiring the emission of electrons at atmospheric pressure, as they offer better control over emission parameters than radioactive electron sources ...
• A compact high-resolution X-ray ion mobility spectrometer 

  Reinecke, Tobias; Kirk, Ansgar T.; Heptner, Andre; Niebuhr, D.; Böttger, S.; Zimmermann, Stefan (College Park, MA : American Institute of Physics (AIP), 2016)

  For the ionization of gaseous samples, most ion mobility spectrometers employ radioactive ionization sources, e.g., containing 63Ni or 3H. Besides legal restrictions, radioactive materials have the disadvantage of a constant ...
• Shutterless ion mobility spectrometer with fast pulsed electron source 

  Bunert, Erik; Heptner, Andre; Reinecke, T.; Kirk, Ansgar T.; Zimmermann, Stefan (College Park, MA : American Institute of Physics (AIP), 2017)

  Ion mobility spectrometers (IMS) are devices for fast and very sensitive trace gas analysis. The measuring principle is based on an initial ionization process of the target analyte. Most IMS employ radioactive electron ...
• A sensitive gas chromatography detector based on atmospheric pressure chemical ionization by a dielectric barrier discharge 

  Kirk, Ansgar T.; Last, Torben; Zimmermann, Stefan (Amsterdam : Elsevier, 2017)

  In this work, we present a novel concept for a gas chromatography detector utilizing an atmospheric pressure chemical ionization which is initialized by a dielectric barrier discharge. In general, such a detector can be ...
• Ion mobility spectrometer with orthogonal X-Ray source for increased sensitivity 

  Bunert, Erik; Reinecke, Tobias; Kirk, Ansgar T.; Bohnhorst, Alexander; Zimmermann, Stefan (Amsterdam : Elsevier, 2018)

  Ion mobility spectrometers (IMS) are compact devices for extremely sensitive detection of proton and electron affine volatile compounds down to low pptv concentrations within less than a second. The measuring principle ...
• A simple centripetal force model for explaining the focusing effect of ion funnels 

  Allers, Maria; Kirk, Ansgar T.; Zimmermann, Stefan (Amsterdam : Elsevier, 2018)

  The ion funnel is one of the key components for transferring ions from higher pressure into vacuum. While known for over twenty years and thoroughly analyzed by mathematical means and simulations, its working principle ...
• Pulsed electron source for atmospheric pressure chemical ionization in ion mobility spectrometry 

  Bunert, Erik; Heptner, Andre; Kirk, Ansgar T.; Käbein, Oliver; Zimmermann, Stefan; Kusch, Alexander; Wurz, Marc Christopher (Piscataway, NJ : IEEE, 2017)

  Ion mobility spectrometers (IMS) are measurement devices for fast and ultra-sensitive trace gas analysis. Most IMS employ radioactive electron sources, such as 3 H or 63 Ni, to provide free electrons with high kinetic ...
• Ionenmobilitätsspektrometrie 

  Kirk, Ansgar T.; Zimmermann, Stefan (Weinheim : Wiley, 2016)

  Ionenmobilitätsspektrometer sind extrem schnelle und sensitive Sensoren für Spurengase, welche diese anhand ihrer Bewegung durch ein Neutralgas unter dem Einfluss eines elektrischen Feldes identifizieren. In diesem Artikel ...

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