• Query Optimization Techniques For Scaling Up To Data Variety 

  Rohde, Philipp Daniel (Hannover : Institutionelles Repositorium der Leibniz Universität Hannover, 2019)

  Even though Data Lakes are efficient in terms of data storage, they increase the complexity of query processing; this can lead to expensive query execution. Hence, novel techniques for generating query execution plans are ...
• The medium isn’t the message: Introducing a measure of adaptive virtual communication 

  Handke, Lisa; Schulte, Eva-Maria; Schneider, Kurt; Kauffeld, Simone (London : Informa UK Limited, 2018)

  Media use can be considered as an integral part of virtual communication and thus of present-day human interaction. Nevertheless, research on media use and effects still largely relies on laboratory experiments, treating ...
• Group Affective Tone and Team Performance: A Week-Level Study in Project Teams 

  Paulsen, Hilko; Klonek, Florian E.; Schneider, Kurt; Kauffeld, Simone (Lausanne : Frontiers Media S.A., 2016)

  Group affective tone is an emergent state that can be shared by group members during interdependent tasks. Groups can experience positive group affective tone (PGAT), a shared feeling of e.g., excitement, enthusiasm, or ...
• Experimental investigation of low-frequency pulsed Lorentz force influence on the motion of Galinstan melt 

  Musaeva, Diana; Ilyin, Vladimir K.; Geža, Vadims; Baake, Egbert (Amsterdam : Elsevier B.V., 2016)

  The paper presents the results of the numerical and physical experiments, aimed at assessing the influence of pulsed force of electromagnetic field on the melt motion and the fluid velocities. The experiment was performed ...
• Automatic refinement of training data for classification of satellite imagery 

  Büschenfeld, Torsten; Ostermann, Jörn (Göttingen : Copernicus GmbH, 2012)

  In this paper, we present a method for automatic refinement of training data. Many classifiers from machine learning used in applications in the remote sensing domain, rely on previously labelled training data. This labelling ...
• Back to the future: origins and directions of the “Agile Manifesto” – views of the originators 

  Hohl, Philipp; Klünder, Jil; Bennekum, Arie van; Lockard, Ryan; Gifford, James; Münch, Jürgen; Stupperich, Michael; Schneider, Kurt (Heidelberg : SpringerOpen, 2018)

  In 2001, seventeen professionals set up the manifesto for agile software development. They wanted to define values and basic principles for better software development. On top of being brought into focus, the manifesto has ...
• Improving spectral efficiency using hybrid system solutions 

  Le Thi, Chung (Hannover : Institutionelles Repositorium der Leibniz Universität Hannover, 2019)

  As frequency bands become increasingly crowded, one of the major research challenges for future wireless communication networks is how to use the radio frequency bands more efficiently. In wireless communication networks, ...
• 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 ...

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