@inproceedings{33296, author = {{Moritzer, Elmar and Netzband, Dennis and Ujma, Andreas }}, title = {{{Messtechnische Ermittlung der Strukurintensität bei spritzgegossenen, faserverstärkten Kunststoffen}}}, year = {{2022}}, } @inproceedings{33355, author = {{Klippstein, Sven Helge}}, location = {{Berlin}}, publisher = {{7. AM Forum Berlin}}, title = {{{Neue Polymerwerkstoffe - Der Schlüssel für die Industrialisierung}}}, year = {{2022}}, } @article{6579, abstract = {{An explicit approach using symplectic time integration in conjunction with traditional finite difference spatial derivatives to solve the wave equation in moving media is presented. A simple operator split of this second order wave equation into two coupled first order equations is performed, allowing these split equations to be solved symplectically. Orders of symplectic time integration ranging from first to fourth along with orders of spatial derivatives ranging from second to sixth are explored. The case of cylindrical acoustic spreading in air under a constant velocity in a 2D square structured domain is considered. The variation of the computed time-of-flight, frequency, and wave length are studied with varying grid resolution and the deviations from the analytical solutions are determined. It was found that symplectic time integration interferes with finite difference spatial derivatives higher than second order causing unexpected results. This is actually beneficial for unstructured finite volume tools like OpenFOAM where second order spatial operators are the state-of-the art. Cylindrical acoustic spreading is simulated on an unstructured 2D triangle mesh showing that symplectic time integration is not limited to the spatial discretization paradigm and overcomes the numerical diffusion arising with the in-built numerical methods which hinder wave propagation.}}, author = {{Inguva, Venkatesh and Feldmann, Nadine and Claes, Leander and Koturbash, Taras and Hahn-Jose, Thomas and Koutcherov, Vladimir and Kenig, Eugeny}}, journal = {{Engineering Reports}}, title = {{{An explicit symplectic approach to solving the wave equation in moving media}}}, doi = {{10.1002/eng2.12573}}, year = {{2022}}, } @inbook{33412, author = {{Schönhärl, Korinna}}, booktitle = {{Ökonomie und Moral im langen 20. Jahrhundert. Eine Anthologie}}, editor = {{Finger, Jürgen and Möckel, Benjamin}}, isbn = {{ISBN 978-3-8353-5200-1}}, pages = {{228–237}}, publisher = {{Wallstein-Verlag}}, title = {{{"Ein Steuerzahler!" Tax education in der frühen Bundesrepublik}}}, year = {{2022}}, } @inproceedings{31070, author = {{Bothe, Mike and Lutters, Nicole and Kenig, Eugeny Y.}}, location = {{Frankfurt am Main}}, title = {{{Untersuchung von Gefahrensituationen bei industriellen Absorption/Desorption-Prozessen mittels dynamischer Simulation}}}, year = {{2022}}, } @article{33497, author = {{Krüger, Jan Tobias}}, journal = {{crystals}}, title = {{{Adjustment of AgCaLa Phases in a FeMn Matrix via LBM for Implants with Adapted Degradation}}}, doi = {{https://doi.org/10.3390/cryst12081146}}, volume = {{12}}, year = {{2022}}, } @inbook{33500, abstract = {{This article is dedicated to piezoelectric ultrasonic power transducers that differ to well known medical ultrasonic diagnostic apparatus or non destructive testing devices by the level of power in use; typically several tens of up to more than thousand watts are used in a multitude of different applications. After a short introduction including historical development, the first focus is on theoretical background of the operating principle, design and mechanical modeling. As piezoelectric elements transform electrical to mechanical energy and vice versa, equivalent circuit modeling is also described. After that, sample applications are delineated by the matter wherein ultrasound generates unique effects: incredible high pressure level as well in air as in water, micro-bubbles generating temperature peaks for very short time instances in fluids, acoustoplastic effect, enhancement of diffusion and recrystallization in solids, friction manipulation, incremental deformation and micro-cracking of surfaces, or even generation of macroscopic movements in motors. At the end, some future directions ranging from novel modeling approaches to advanced control and new materials are addressed.}}, author = {{Hemsel, Tobias and Twiefel, Jens}}, booktitle = {{Reference Module in Materials Science and Materials Engineering}}, isbn = {{978-0-12-803581-8}}, keywords = {{Equivalent circuit model, Langevin transducer, Lumped parameter model, Piezoelectric transducer, Ultrasonic processes, Ultrasound}}, publisher = {{Elsevier}}, title = {{{Piezoelectric Ultrasonic Power Transducers}}}, doi = {{10.1016/b978-0-12-819728-8.00047-4}}, year = {{2022}}, } @inproceedings{33522, author = {{Bernemann, Sören Antonius and Maćkowiak, Jan and Maćkowiak, Jerzy and Bertling, René and Lutters, Nicole and Kenig, Eugeny}}, keywords = {{CFD, simulation, agricultural waste, multiphase}}, location = {{Frankfurt am Main}}, title = {{{Development of an innovative separation unit for nitrogen recovery from agricultural waste}}}, year = {{2022}}, } @article{33523, abstract = {{Die thermisch verursachte, plastische Verformung an statischen Druckplatten von Lamellenbremsen kann das Betriebsverhalten von Bremsen nachhaltig stören und sollte daher vermieden werden. So kann die plastische Verformung der Druckplatte beispielsweise zu einer Verkleinerung des Luftspalts führen und ungewollte Veränderung der Reibverhältnisse verursachen. Während des Bremsvorgangs dehnen sich hoch erwärmte Bereiche nah der Reibfläche aus und werden von den Zonen geringerer Temperatur an ihrer Ausdehnung gehindert. Überschreiten die daraus resultierenden Spannungen die Dehngrenze des Materials, kommt es zu plastischer Verformung. Dieser Artikel erläutert den physikalischen Verformungsprozess detailliert und darauf aufbauend, welche Maßnahmen zu einer Verringerung der Verformung ergriffen werden können. Dazu werden im Rahmen theoretischer Vorüberlegungen drei Ansätze identifiziert, die sowohl die Geometrie als auch die Werkstoffe der Druckplatten betreffen. Radiale Schlitze sollen die Behinderung der thermischen Dehnung verhindern und dadurch Spannungen reduzieren; die Werkstoffauswahl auf Basis der Thermoschockempfindlichkeit reduziert die plastische Verformung. Anhand einer kombinierten Simulation der Thermik und der Mechanik einer Druckplatte wird der Effekt dieser Ansätze an vier Varianten der Druckplatte überprüft. Experimentelle Untersuchungen an realen Prototypen der Druckplattenvarianten bestätigen die Ergebnisse der Simulation und weisen die Wirksamkeit der vorgeschlagenen Maßnahmen zur Reduzierung der plastischen Verformung nach.}}, author = {{Schadomsky, Magnus and Blumenthal, Lars Martin and Zimmer, Detmar and Peter, Simon and Boros, Laszlo}}, issn = {{0015-7899}}, journal = {{Forschung im Ingenieurwesen}}, keywords = {{General Engineering, Bremsen, Bremsscheiben, thermoplastische Verformung}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{Maßnahmen zur Reduzierung von plastischer Verformung an statischen Druckplatten von Lammellenbremsen infolge einseitig eingebrachter hoher Reibleistung}}}, doi = {{10.1007/s10010-022-00601-2}}, year = {{2022}}, } @phdthesis{33499, author = {{Otroshi, Mortaza}}, isbn = {{978-3-8440-8777-2}}, issn = {{1434-6915}}, pages = {{128}}, publisher = {{Shaker Verlag}}, title = {{{Damage modeling in the numerical simulation of mechanical joining processes}}}, doi = {{https://doi.org/10.2370/9783844087772}}, year = {{2022}}, } @inproceedings{30123, author = {{Otroshi, Mortaza and Meschut, Gerson}}, location = {{Pittsburg, Pennsylvania, USA}}, title = {{{Investigation of the three-dimensional stress state during loading of self-piercing riveted joints}}}, year = {{2022}}, } @inproceedings{33561, author = {{Tews, Karina and Teutenberg, Dominik and Meschut, Gerson}}, location = {{Blankenburg (Harz)}}, title = {{{Experimentelle Untersuchung des Ermüdungsverhaltens und Berechnung der Lebensdauer von Stahlklebverbindungen bei multiaxialer Belastung}}}, year = {{2022}}, } @inbook{33728, author = {{Bielak, C. R. and Böhnke, M. and Bobbert, M. and Meschut, G.}}, booktitle = {{The Minerals, Metals & Materials Series}}, isbn = {{9783031062117}}, issn = {{2367-1181}}, publisher = {{Springer International Publishing}}, title = {{{Development of a Numerical 3D Model for Analyzing Clinched Joints in Versatile Process Chains}}}, doi = {{10.1007/978-3-031-06212-4_15}}, year = {{2022}}, } @article{33859, author = {{Moritzer, Elmar and Elsner, Christian Lennart}}, journal = {{Macromolecular Symposia}}, location = {{Bukarest}}, number = {{1}}, publisher = {{Wiley}}, title = {{{Investigation and Improvement of Processing Parameters of a Copper-Filled Polymer Filament in Fused Filament Fabrication as a Basis for the Fabrication of Low-Porosity Metal Parts}}}, doi = {{https://doi.org/10.1002/masy.202100390}}, volume = {{404}}, year = {{2022}}, } @article{33861, author = {{Moritzer, Elmar and Wächter, Julian}}, journal = {{Macromolecular Symposia}}, location = {{Bukarest}}, number = {{1}}, publisher = {{Wiley}}, title = {{{Development of a Procedure for the Assessment of Material Potentials under Consideration of the Weld Seam Quality for Multi-Material Applications in the FDM Process}}}, doi = {{https://doi.org/10.1002/masy.202100389}}, volume = {{404}}, year = {{2022}}, } @book{33865, abstract = {{Lightweight materials such as aluminium and ultra-high-strength steel are increasingly being used in modern material mixed design in car body construction. As a fixing method for hybrid joining with structural adhesive, clinching has the advantage over other mechanical joining technologies that different materials can be joined without an auxiliary joining part and pre-hole. Due to the large degree of deformation in the joining partners, strong in-plane and out-of-plane material flows occur during the setting process, which can lead to plastic deformation. The aim of this work is the further development of shear-clinching for low-deformation of aluminium-steel joints. To gain a basic understanding of the joint deformation, the deformation of the joint partners during the setting process is identified step by step. Based on the knowledge gained, the deformation-related influencing factors are investigated experimentally. Thus, optimisation approaches as well as suggested handling methods for the production of a low-deformation shear-clinching joint are derived. For the realisation of the common narrow flange, which is to be characterised as deformation-sensitive due to a small edge distance, a numerically supported tool modification is carried out and subsequently experimentally validated. }}, author = {{Han, Daxin}}, title = {{{Deformationsarme Fügeverbindungen mittels prozessoptimiertem Schneidclinchen}}}, year = {{2022}}, } @article{33385, abstract = {{Abstract Background In Sub-Saharan African countries, rapid urbanization and increasing socio-economic status are associated with a transition to decreased physical activity (PA). A more sedentary lifestyle is linked to increased body fat leading to increments in leptin levels. Since rodent and human studies in high-income countries have shown that starvation-induced hypoleptinemia triggers high PA, efforts are warranted to pursue the hypothesis that low leptin levels in lean children of low- and middle-income countries (LMIC) are also associated with high PA. Methods In this cross-sectional study, we assessed seven-day PA with triaxial accelerometry (ActiGraph GT3X) among 223 primary school children (9 to 12 years of age) in rural Tanzania. Moderate-to-vigorous PA (MVPA) and total accelerometer counts per day were outcome variables. Leptin was determined using enzyme linked immunosorbent assay tests from dried blood spots. Anthropometric assessments were conducted and food insecurity and socio-demographic data were gathered using semi-structured interviews. Results In this sample of school children in rural Tanzania, leptin concentrations (median: 0.91 ng/mL, P25: 0.55, P75: 1.69), body mass index z-scores (median: -1.35, P25: -1.93, P75: -0.82), and height-for-age-z-scores (median: -1.16, P25: -1.96, P75: -0.61) were low. In contrast, PA levels were high with a median MVPA time of 119 min/day. Linear regression confirmed that leptin levels were negatively associated with MVPA (beta: -18.1; 95%CI: -29.7; -6.5; p = 0.002) and total accelerometer counts (beta: -90,256; 95%CI: -154,146; -26,365; p = 0.006). Children residing in areas with better infrastructure had lower MVPA levels (p < 0.001) and tended to have higher leptin levels (p = 0.062) than children residing in areas only reachable via dirt roads. Conclusion Our cross-sectional field study is the first that supports the hypothesis of low leptin levels as a potential endocrine trigger of high PA in lean children of a LMIC. We observed early signs of a PA transition towards a less active lifestyle in a subgroup residing in areas with better infrastructure that concomitantly tended to have higher leptin concentrations. Considering that area-dependent PA differences were more pronounced among girls than boys, whereas differences in leptin levels were less pronounced, not only biological, but also external factors explain PA transition. }}, author = {{Ludwig, Christine and Knoll-Pientka, Nadja and Mwanri, Akwilina and Erfle, Celina and Onywera, Vincent and Tremblay, Mark S. and Bühlmeier, Judith and Luzak, Agnes and Ferland, Maike and Schulz, Holger and Libuda, Lars and Hebebrand, Johannes}}, issn = {{1471-2458}}, journal = {{BMC Public Health}}, keywords = {{Public Health, Environmental and Occupational Health}}, number = {{1}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{Low leptin levels are associated with elevated physical activity among lean school children in rural Tanzania}}}, doi = {{10.1186/s12889-022-12949-9}}, volume = {{22}}, year = {{2022}}, } @inproceedings{33972, author = {{Mügge, Nils and Kronberg, Alexander and Glushenkov, Maxim and Inguva, Venkatesh and Kenig, Eugeny Y.}}, booktitle = {{1st Conference on Energy, Environment and Digital Transition E2DT}}, location = {{Mailand, Italien}}, title = {{{A Thermal Model for Recuperative Heat Engines Operating with Dense Working Fluids}}}, year = {{2022}}, } @article{33988, author = {{Moritzer, Elmar and Driediger, Christine}}, issn = {{1022-1360}}, journal = {{Macromolecular Symposia}}, keywords = {{digital light processing, material combination, reactive direct bonding, vat photopolymerization}}, number = {{1}}, publisher = {{Wiley}}, title = {{{Reactive Direct Bonding of Digital Light Process Components}}}, doi = {{10.1002/masy.202100396}}, volume = {{404}}, year = {{2022}}, } @misc{33987, author = {{Moritzer, Elmar and Elsner, Christian Lennart}}, booktitle = {{Kunststoffe}}, issn = {{0023–5563}}, title = {{{Mit Gestaltungsrichtlinien zum Erfolg}}}, volume = {{11/2022}}, year = {{2022}}, }