Repository for natural sciences and technology
This repository provides free access to scientific publications from the fields of natural sciences and technology (open access). All authors may use RENATE free of charge to publish their research findings from natural sciences and technology, regardless their institutional affiliation. The publications deposited in this repository are permanently freely accessible and citable. The repository is operated by Technische Informationsbibliothek (TIB).In addition, RENATE serves as repository for the publication of reports to federally funded research projects (all subjects), e.g. funded by the Federal ministry of Research, Technology and Space. RENATE is also the recommended publishing place for reports to research projects funded by German Research Foundation (DFG) in the fields of natural sciences and technology. Information on uploading your research report can be found at tib.eu/dtf.

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- ItemAbschlussbericht HPC-UKF - Umweltfreundliches, kundenfreundliches und flächendeckendes High Power Charging(Hannover : Technische Informationsbibliothek, 2024-10-30) Esser, Marcel; von Haebler, JonasDatei-Upload durch TIB
- ItemVerbundprojekt: UAV/USV-Tandemsystems zur hochaufgelösten Datenerfassung an der Wasserstraße – RiverCloud; Entwicklung eines autonomen und vernetzten UAV/USV-Tandemsystems für die Erfassung und Bereitstellung von hochaufgelösten Daten zum Gewässermanagement sowie Ausbau und Unterhaltung von Wasserstraßen(Hannover : Technische Informationsbibliothek, 2024-06) Blankenbach, Jörg; Becker, Ralf; Chen, Siyu; Schelder, Martina; Weber, Frank-Andreas; Hoffmann, Magnus; Wehmeyer, David; Ramirez, Juan; Neumann, Enrico; Düster, Rudolf; Hansen, Issa; Teege, Julian; Drummer, Clara; Artz, Thomas; Heuner, Maike; Eberhardt, Benjamin; Leismann, Kristiina; Gattung, ThomasDatei-Upload durch TIB
- ItemInvestigation of Different Pole Configurations in New Asymmetric Permanent Magnet Synchronous Reluctance Machines(New York, NY : IEEE, 2025-01-13) Ajamloo, Akbar Mohammadi; Ghaheri, Aghil; Ibrahim, Mohamed N.; Sergeant, PeterThis paper investigates the impact of pole number and configuration on key performance characteristics of a new family of asymmetric permanent magnet synchronous reluctance machines (PMSynRMs). New variants of asymmetric PMSynRMs are presented here which integrate distinct interior PM (IPM) poles and reluctance poles into a single lamination. The torque enhancement principle relies on segregating the net torque into components generated by each pole type. Torque enhancement is achieved by optimally shifting the IPM poles relative to the reluctance poles, aligning the torque peaks generated by each pole type. A comprehensive comparative analysis is conducted between the proposed asymmetric and conventional topologies, with identical PM volume, copper loss, frequency, and frame size. The analysis evaluates torque production capability, unbalanced magnetic forces, torque ripple, losses, and power factor. The results reveal that the asymmetric PMSynRMs offer improved torque, power factor, and reduced torque ripple compared to conventional designs for pole numbers 4, 6, 8, and 10. However, some asymmetric designs exhibit the drawback of unbalanced magnetic forces, which should be taken into consideration. Finally, an asymmetric PMSynRM is prototyped and tested to verify the simulation results.
- ItemProperties of Additively Manufactured Soft and Hard Magnetic Cores for Electrical Machines: Methods and Materials − A Review(New York, NY : IEEE, 2025-05-20) Ajamloo, Akbar Mohammadi; Ibrahim, Mohamed N.; Sergeant, PeterAdditive Manufacturing (AM) is an emerging topic in the field of electrical machines (EMs), offering the potential to overcome challenges imposed by conventional manufacturing methods. This paper provides an overview of various AM methods and materials used to manufacture soft and hard magnetic cores for EMs, with a particular focus on their multiphysics properties. Since each AM method involves unique processes—such as particle bonding, melting, or sintering—the resulting microstructural properties of the printed cores differ, leading to varied multi-physics characteristics that require indepth study. The paper outlines both the benefits and challenges associated with AM techniques and materials. Importantly, it explores the detailed properties of Fe-Si and Fe-Co soft magnetic cores as well as hard magnetic cores including NdFeB, ferrite, and alnico printed through different AM methods, comparing them to traditional laminations and commercial hard magnets.
- ItemPrinciple of Torque-Axis Alignment in New Asymmetric PM Synchronous Reluctance Machines: Toward Less-Rare-Earth PM Machines(Piscataway, NJ : IEEE, 2024-12-05) Ajamloo, Akbar Mohammadi; Ghaheri, Aghil; Ibrahim, Mohamed N.; Sergeant, PeterThis article reveals the principle of a new torque-axis alignment technique as the basis for a new class of asymmetric permanent magnet synchronous reluctance machines (PMSynRMs). These machines are characterized by having distinct permanent magnet (PM) and SynRM poles. The objective is to precisely align peak torque from each pole type by adjusting the relative shift angle, minimizing the rare-Earth PM usage. A new analytical model is proposed, segregating torque generated by each pole type in a rotating dq reference frame. The impact of PM pole configuration—surface PM (SPM) and interior PM (IPM)—is examined, and the effects of cross-coupling and saturation are investigated. Two different torque separation models are used to describe key torque characteristics of the machines. The analysis indicates that the asymmetric IPMSynRM and SPMSynRM offer the same torque rating at a significantly lower PM volume usage compared with the conventional PM-assisted synchronous reluctance machine (PMaSynRM). In addition, it is observed that asymmetric IPMSynRM exhibits superior torque performance compared with asymmetric SPMSynRM, attributed to additional reluctance torque generated by IPM poles. Finally, a prototype is manufactured and tested to evaluate the presented principle in the asymmetric topologies.
- ItemDetektion von küstenhydrologischen Phänomenen und Artefakten in minütlichen Tidepegeldaten; Detektion von fehlerhaften Messungen und Artefakten sowie Bewertung in Abhängigkeit standortspezifischer und phänomenologischer Charakteristik (DePArT A); Entwurf und Realisierung von Algorithmen zur Detektion von küstenhydrologischen Phänomenen und anthropogenen Einflüssen in minütlichen Tidepegeldaten (DePArT B)(Hannover : Technische Informationsbibliothek, 2023) Soltau, Felix; Jensen, Jürgen; Kaehler, Christian; Arns, ArneDatei-Upload durch TIB
- ItemaZuR - automatisierte Zustandserfassung der Radwegeinfrastruktur(Hannover : Technische Informationsbibliothek, 2025-04-30) Lohmeier, Martina; Boeva, Alina; Van Zeebroeck, Thibe; Kühl, Jana; Michael, Moritz; Lorenzl, Holger; Rohwedder, JasminIm Rahmen der Förderung einer klimaschonenden Mobilität gewinnt das Fahrrad in Deutschland zunehmend an Bedeutung. Eine Umfrage zeigt, dass 39 % der Befragten regelmäßig das Fahrrad nutzen, während 46 % dies in Zukunft häufiger tun möchten. Ein wesentlicher Hemmfaktor ist der schlechte Zustand der Radwege, der bei 38 % der Befragten Unsicherheiten im Straßenverkehr hervorruft. Um den Radverkehr zu stärken, ist es unerlässlich, die Radwege zu verbessern, wofür eine fundierte Datengrundlage notwendig ist. Während das Erhaltungsmanagement für Straßeninfrastrukturen etabliert ist, befindet sich das für Radwege noch in der Entwicklungsphase. Aktuelle Regelwerke bieten unzureichende Definitionen und Kriterien für die Zustandserfassung von Radinfrastrukturen. Dieses Forschungsprojekt, aZuR – automatisierte Zustandserfassung und -bewertung von Außerortsradwegen, zielt darauf ab, ein System zu entwickeln, das mithilfe von LiDAR-Technologie eine effiziente und automatisierte Bewertung der Radwegoberflächen ermöglicht. Durch hochauflösende Oberflächenbilddaten soll die Genauigkeit der Zustandsbewertungen verbessert werden, um eine datengestützte Grundlage für Erneuerungs- und Ausbauentscheidungen zu schaffen. Das Projekt untersucht zudem die Genauigkeit der automatisierten LiDAR-Messdaten im Vergleich zur visuellen Erfassung nach bestehenden Regelwerken, um eine solide Basis für zukünftige Bewertungsverfahren und Qualitätsstandards zu schaffen.
- ItemOptimisation of Additively Manufactured Hairpin Windings for High Power Density Traction Motors(Piscataway, NJ : IEEE, 2025-07-04) Tesfamikael, Hadish Habte; Notari, Riccardo; Murataliyev, Mukhammed; Wang, Meiqi; Gerada, Chris; Degano, MicheleDespite the widespread use of hairpin winding (HW) in electric vehicle (EV) traction motors, several AC loss phenomena hinder its broader application at higher operating frequencies. This paper investigates methods for reducing AC copper losses, focusing on both design approaches and advanced manufacturing techniques, particularly additive manufacturing (AM). A comprehensive analysis of various HW layouts is conducted, evaluating AC copper losses through finite element (FE) and analytical approaches, while considering the effects of circulating currents and short pitching. Detailed analysis of a HW motor is performed to address the influence of magnetic saturation and rotor-magnetomotive force (MMF) on AC copper losses. Moreover, sizing of HW dimensions at a specific operating speed is carried out analytically and validated using FE analysis, with the aim of minimizing high-frequency losses. The potential of AM to enhance manufacturing flexibility and facilitate conductor size optimization is briefly explored. A case study with in-depth optimization is performed to determine the optimal HW dimensions at representative operating points along the torque-speed curve. As a result, the most suitable HW design for EV applications is proposed and benchmarked against results from rigorous optimization processes.
- ItemHelP - Hocheffiziente leistungsstarke Plasmastromquelle(Hannover : Technische Informationsbibliothek, 2025-06-30) Friedel, Jens; Laurisch, Markus; Päge, Maximilian; Strothmann , Benjamin; Schafmeiser, Frank; Zeiter, Oleg; Bönisch, Sven; Wällnitz, Robert; Lasslop, Markus; Orlob, HolgerAs part of the "HelP - Highly Efficient, High-Performance Plasma Power Source" project, an innovative power source for plasma cutting was developed that impresses with its increased efficiency and grid compatibility. The goal was to increase the efficiency of the power source through soft-switching converter topologies and reduce electrical energy consumption. The use of novel wide-bandgap semiconductors (silicon carbide SiC) enabled a significant reduction in switching losses. The project encompassed the conception, design, and control development, as well as the construction of functional prototypes and demonstrators. The results show a reduction in losses by almost tow thirds, with an efficiency of 95.8% at 8 kW. This resulted in a grid-friendly PFC rectifier circuit and a soft-switching current-controlled interleaved switching LLC resonant converter circuit. The partially successful implementation of the technical objectives and the preparation of a demonstrator for use in a plasma cutting system underscore the relevance of the project for energy efficiency in industry.
- ItemFakeNarratives - Narrative der Desinformation verstehen: ein Vergleich zwischen öffentlich-rechtlichen und alternativen Nachrichtenvideos; Teilvorhaben L3S: Multimodale Informationsextraktion aus Nachrichtenvideos(Hannover : Technische Informationsbibliothek, 2025-07-08) Müller-Budack, Eric; Cheema, Gullal S.; Ewerth, RalphDie digitale Medienlandschaft und soziale Medien haben die Informationsverbreitung grundlegend verändert. Dies hat zu diversen Herausforderungen bei der Unterscheidung von glaubwürdigen Nachrichten von Desinformation geführt. Desinformationen können nicht nur durch falsche Fakten, Deep Fakes etc. verbreitet werden, sondern auch durch narrative Muster der Desinformation. Das Ziel des Projekts FakeNarratives war es, Narrative der Desinformation durch einen Vergleich von öffentlich-rechtlichen und alternativen Nachrichtenvideos zu verstehen. Hierfür wurde ein interdisziplinärer Ansatz verfolgt, der Methoden aus den Digital Humanities, der Informatik und der multimodalen Semiotik verknüpft. Der Fokus des Teilprojekts L3S bestand in der Entwicklung von Ansätzen zur multimodalen Merkmalsextraktion aus Nachrichtenvideos mit aktuellen Ansätzen aus der Audioanalyse, des maschinellen Sehens und der natürlichen Sprachverarbeitung. Zudem wurde ein (semi-)automatischer Ansatz zur Erkennung von narrativen Muster in Nachrichtenvideos entwickelt.