@article{45602, author = {{Karakaya, Yasin and Somnitz, H. and Hermsen, A. and Gonchikzhapov, Munko and Kasper, Tina}}, issn = {{2666-352X}}, journal = {{Applications in Energy and Combustion Science}}, keywords = {{Metastable particles, Nanomaterials, Quartz-crystal-microbalance, Molecular-beam mass spectrometry, Tetramethylsilane, Reaction kinetics}}, publisher = {{Elsevier BV}}, title = {{{Revisiting the initial reaction rates for TMS combustion and a new evidence for metastable silica nanoparticles in the gas-phase synthesis}}}, doi = {{10.1016/j.jaecs.2023.100152}}, volume = {{14}}, year = {{2023}}, } @inbook{46691, author = {{Dahms, Frederik and Homberg, Werner}}, booktitle = {{Lecture Notes in Mechanical Engineering}}, isbn = {{9783031410222}}, issn = {{2195-4356}}, location = {{Cannes, France}}, publisher = {{Springer Nature Switzerland}}, title = {{{Analysis and Modelling of the Deformation in the Manufacture of Flange-Contours by the Combined Friction-Spinning and Flow-Forming Process}}}, doi = {{10.1007/978-3-031-41023-9_72}}, year = {{2023}}, } @article{46483, abstract = {{The demands on joining technology are constantly increasing due to the consistent lightweight construction and the associated increasing material mix. To meet these requirements, the adaptability of the joining processes must be improved to be able to process different material combinations and to react to challenges caused by deviations in the process chain. One example of a highly adaptable process due to the two-step process sequence is thermomechanical joining with Friction Spun Joint Connectors (FSJCs) that can be individually adapted to the joint. In this paper, the potentials of the adaption in the two-stage joining process with aluminium auxiliary joining elements are investigated. To this end, it is first investigated whether a thermomechanical forming process can be used to achieve a uniform and controlled manufacturing regarding the process variable of the temperature as well as the geometry of the FSJC. Based on the successful proof of the high and good repeatability in the FSJC manufacturing, possibilities, and potentials for the targeted influencing of the process and FSJC geometry are shown, based on an extensive variation of the process input variables (delivery condition and thus mechanical properties of the raw parts as well as the process parameters of rotational speed and feed rate). Here it can be shown that above all, the feed rate of the final forming process has the strongest influence on the process and thus also offers the strongest possibilities for influencing it.}}, author = {{Borgert, Thomas and Henke, Maximilian and Homberg, Werner}}, issn = {{2504-4494}}, journal = {{Journal of Manufacturing and Materials Processing}}, keywords = {{Industrial and Manufacturing Engineering, Mechanical Engineering, Mechanics of Materials}}, number = {{4}}, publisher = {{MDPI AG}}, title = {{{Investigations on the Influences of the Thermomechanical Manufacturing of Aluminium Auxiliary Joining Elements}}}, doi = {{10.3390/jmmp7040147}}, volume = {{7}}, year = {{2023}}, } @inbook{46752, abstract = {{Due to current global challenges regarding energy security as well as climate change the importance of preserving the nature and all available resources is steadily increasing. In order to achieve the energy-saving and climate targets, it is not only necessary to develop new processes and processing possibilities, but also to optimise known process chains with regard to energy and resource efficiency in the area of production technology. Here, the recycling of supposed production waste represents an opportunity to save energy. In addition to the conventional and smelting metallurgical recycling process, extensive research activities have therefore been carried out for alternative solid-state recycling processes. One example is the friction-induced recycling process, which has been used in past studies to demonstrate the energy- and resource-efficient production of semi-finished products from aluminium scrap such as chips. In addition, properties like chemical composition and strength can be adjusted locally and in terms of processing time. This can be used to improve the versatility of further processing steps.}}, author = {{Borgert, Thomas and Homberg, Werner}}, booktitle = {{Lecture Notes in Mechanical Engineering}}, isbn = {{9783031413407}}, issn = {{2195-4356}}, publisher = {{Springer Nature Switzerland}}, title = {{{Friction-Induced Recycled Aluminium Semi-finished Products in Thermo-mechanical Joining Technology}}}, doi = {{10.1007/978-3-031-41341-4_1}}, year = {{2023}}, } @inproceedings{46762, author = {{Tchomgue Simeu, Arnold and Mahnken, Rolf}}, booktitle = {{XI International Conference on Adaptive Modeling and Simulation}}, publisher = {{CIMNE}}, title = {{{Mesh- and model adaptivity for elasto-plastic mean-field and full-field homogenization based on downwind and upwind approximations}}}, doi = {{10.23967/admos.2023.054}}, year = {{2023}}, } @article{46736, author = {{Pfister, Daniel and Jackson, Robin C and Güldenpenning, Iris and Williams, A Mark}}, journal = {{Human Movement Science}}, pages = {{103092}}, publisher = {{Elsevier}}, title = {{{Timing a fake punch: Inhibitory effects in a boxing-specific spatial attention task}}}, doi = {{https://doi.org/10.1016/j.humov.2023.103092}}, volume = {{89}}, year = {{2023}}, } @article{46815, abstract = {{In this work, the influence of the filler–matrix adhesion on the tensile properties of laser-sintered parts built with Polyamide 613 filled with glass beads was investigated. For this purpose, dry blends of glass beads with and without organosilane coupling agents and polyamide powder were prepared and processed into tensile specimens on an EOS P396 laser sintering system. The samples were tested both in the dry state and after an accelerated conditioning in a climate chamber. Furthermore, finite element method (FEM) simulations were performed to model the extreme cases of optimum adhesion and no adhesion. By correlating the tensile tests with the simulation results and by analyzing the fracture surfaces, it was shown that the filler–matrix adhesion is sufficient in the dry state but is strongly degraded by conditioning. Even the presence of various organosilane thin films could not prevent a strong deterioration of the filler–matrix adhesion and the associated deterioration of the mechanical properties. Since a comparison with an injection-molded sample of the same polymer filler combination shows identical behavior after conditioning, it is assumed that this problem is not limited to additively manufactured parts.}}, author = {{Kletetzka, Ivo and Kosanke, Maren and Meinderink, Dennis and Neßlinger, Vanessa and Grundmeier, Guido and Schmid, Hans-Joachim}}, issn = {{2363-9512}}, journal = {{Progress in Additive Manufacturing}}, keywords = {{Industrial and Manufacturing Engineering}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{Influence of the filler–matrix adhesion and the effects of conditioning on tensile properties of laser-sintered parts built with polyamide–glass bead dry blends}}}, doi = {{10.1007/s40964-023-00501-z}}, year = {{2023}}, } @article{43046, abstract = {{In the laser sintering technology, the semi-crystalline polymer material is exposed to elevated temperatures during processing, which leads to serious material ageing for most materials. This has already been investigated intensively by various authors. However, the ageing of the material at ambient temperatures during shelf life has not been the focus so far. The need to analyse the shelf life can be derived from an ecological and economic point of view. This work is focusing on the shelf life of PA2200 (PA12). To reduce the potential influences of powder production fluctuations, two different powder batches stored for 5.5 years and 6.5 years are investigated and compared to a reference powder produced 0.5 years before these investigations. Multiple powder analyses and part characterisations have been performed. A significant yellowing and molecular chain length reduction can be derived from the measurement results. Whereas the influence on mechanical part performance was minor, the parts built with the stored powders are more yellowish. As it is most likely that this is due to the consumption of polyamide stabilisers, it can be assumed that these parts will be subject to significantly faster ageing. Therefore, it is still not recommended to use the stored powders for critical parts or light intense and humid environments.}}, author = {{Klippstein, Sven Helge and Kletetzka, Ivo and Sural, Ilknur and Schmid, Hans-Joachim}}, journal = {{The International Journal of Advanced Manufacturing Technology }}, keywords = {{Selective laser sintering, Shelf life, Polyamide 12, powder, PA2200, material ageing}}, publisher = {{Springer}}, title = {{{Influence of a prolonged shelf time on PA12 laser sintering powder and resulting part properties}}}, doi = {{https://doi.org/10.1007/s00170-023-11243-1}}, year = {{2023}}, } @article{37466, abstract = {{Typically, head fakes in basketball are generated to, and actually do, deteriorate performance on the side of the observer. However, potential costs at the side of the producer of a fake action have only rarely been investigated before. It is thus not clear yet if the benefit (i.e., slowed reactions in the observer) of performing a head fake is overestimated due to concurrently arising fake production costs (i.e., slowed performance in the producer of a head fake). Therefore, we studied potential head-fake production costs with two experiments. Novice participants were asked to generate passes to the left or right side, either with or without head fakes. In Experiment 1, these actions were determined by an auditory stimulus (i.e., a 440 Hz or 1200 Hz sinus or jigsaw wave). After an interstimulus interval (ISI) of either 0 ms, 800 ms, or 1500 ms, which served the preparation of the action, the cued action had to be executed. In Experiment 2, passing to the left or right, either with or without a head fake, was determined by a visual stimulus (i.e., a player with a red or blue jersey defending either the right or left side). After an ISI of either 0 ms, 400 ms, 800 ms, or 1200 ms, the cued action had to be executed. In both experiments, we observed higher reaction times (RTs) for passes with head fakes as compared to passes without head fakes for no and an intermediate preparation interval (from ISI 0 ms to 800 ms), but no difference for a long preparation interval (for an ISI of 1200 ms and 1500 ms). Both experiments show that generating fake actions produces performance costs, however, these costs can be overcome by a longer preparation phase before movement execution.}}, author = {{Güldenpenning, Iris and Weigelt, Matthias and Böer, Nils Tobias and Kunde, Wilfried}}, issn = {{0167-9457}}, journal = {{Human Movement Science}}, keywords = {{Experimental and Cognitive Psychology, Orthopedics and Sports Medicine, General Medicine, Biophysics}}, publisher = {{Elsevier BV}}, title = {{{Producing deceptive actions in sports: The costs of generating head fakes in basketball}}}, doi = {{10.1016/j.humov.2022.103045}}, volume = {{87}}, year = {{2023}}, } @article{47065, abstract = {{The reform of the European academic landscape with the introduction of bachelor's and master's degree programs has brought about several profound changes for teaching and assessment in higher education. With regard to the examination system, the shift towards output-oriented teaching is still one of the most significant challenges. Assessments have to be integrated into the teaching and learning arrangements and consistently aligned towards the intended learning outcomes. In particular, assessments should provide valid evidence that learners have acquired competences that are relevant for a specific domain. However, it seems that this didactic goal has not yet been fully achieved in modeling education in computer science. The aim of this study is to investigate whether typical task material used in exercises and exams in modeling education at selected German universities covers relevant competences required for graphical modeling. For this purpose, typical tasks in the field of modeling are first identified by means of a content-analytical procedure. Subsequently, it is determined which competence facets relevant for graphical modeling are addressed by the task types. By contrasting a competence model for modeling with the competences addressed by the tasks, a gap was identified between the required competences and the task material analyzed. In particular, the gap analysis shows the neglect of transversal competence facets as well as those related to the analysis and evaluation of models. The result of this paper is a classification of task types for modeling education and a specification of the competence facets addressed by these tasks. Recommendations for developing and assessing student's competences comprehensively are given.}}, author = {{Soyka, Chantal and Ullrich, Meike and Striewe, Michael and Schaper, Niclas}}, journal = {{Enterprise Modelling and Information Systems Architectures}}, keywords = {{conceptual modeling, higher education, competence-oriented assessment, task analysis, graphical modeling}}, title = {{{Comparison of Required Competences and Task Material in Modeling Education}}}, doi = {{10.18417/EMISA.18.7}}, volume = {{18}}, year = {{2023}}, } @inproceedings{46957, abstract = {{Modern companies often face various challenges in concept development of products or systems. Design engineers prepare initial concepts as 3D models. These are then simulated by computational engineers. If requirements are not met, this necessitates an iterative process that runs between the design and computation departments until a valid concept is created. Design methods such as topology optimization are often used here. The upcoming result is then attempted to be adapted to certain manufacturing processes. These iteration loops can sometimes take a very long time, since the model construction and structural optimization generate large computational efforts. The present work shows on an example a methodical approach, which represents a first proof of concept, to solving this problem, including a description of methods and techniques, as well as possible problems in a detailed analysis concerning training data for neural networks and their abstraction capabilities. It is evident that additional research work needs to be conducted for further utilization in order to address all arising questions.}}, author = {{Ott, Manuel and Meihöfener, Niclas and Mozgova, Iryna}}, booktitle = {{Proceedings of the 34rd Annual International Solid Freeform Fabrication Symposium 2023}}, editor = {{Ott, Manuel}}, location = {{Austin, Texas, United States}}, title = {{{Methodical Approach to Reducing Design Time by using Neural Networks in Early Stages of Concept Development}}}, year = {{2023}}, } @article{47122, abstract = {{AbstractFeCo alloys are important materials used in pumps and motors in the offshore oil and gas drilling industry. These alloys are subjected to marine environments with a high NaCl concentration, therefore, corrosion and catastrophic failure are anticipated. So, the surface dissolution of additively manufactured FeCo samples is investigated in a quasi-in situ manner, in particular, the pitting corrosion in 5.0 wt pct NaCl solution. The local dissolution of the same sample region is monitored after 24, 72, and 168 hours. Here, the formation of rectangular and circular pits of ultra-fine dimensions (less than 0.5 µm) is observed with increasing immersion time. In addition, the formation of a corrosion-inhibiting surface layer is detected on the sample surface. Surface dissolution leads to a change in the surface structure, however, no change in grain shape or grain size is noticed. The surface topography after local dissolution is correlated to the grain orientation. Quasi-in situ analysis shows the preferential dissolution of high-angle grain boundaries (HAGBs) leading to a change in the fraction of HAGBs and low-angle grain boundaries fraction (LAGBs). For the FeCo sample, a potentiodynamic polarisation test reveals a corrosion potential (Ecorr) of − 0.475 V referred to the standard hydrogen electrode (SHE) and a corrosion exchange current density (icorr) of 0.0848 A/m2. Furthermore, quasi-in situ experiments showed that grains oriented along certain crystallographic directions are corroding more compared to other grains leading to a significant decrease in the local surface height. Grains with a plane normal close to the $$\langle {1}00\rangle$$ ⟨ 100 ⟩ direction reveal lower surface dissolution and higher corrosion resistance, whereas planes normal close to the $$\langle {11}0\rangle$$ ⟨ 110 ⟩ direction and the $$\langle {111}\rangle$$ ⟨ 111 ⟩ direction exhibit a higher surface dissolution.}}, author = {{Pramanik, Sudipta and Krüger, Jan Tobias and Schaper, Mirko and Hoyer, Kay-Peter}}, issn = {{1073-5623}}, journal = {{Metallurgical and Materials Transactions A}}, keywords = {{Metals and Alloys, Mechanics of Materials, Condensed Matter Physics}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{Quasi-In Situ Localized Corrosion of an Additively Manufactured FeCo Alloy in 5 Wt Pct NaCl Solution}}}, doi = {{10.1007/s11661-023-07186-7}}, year = {{2023}}, } @article{47117, abstract = {{Trotz der Annahme, dass Langzeitpraktika im Lehramts-studium hohe Belastungen für Studierende darstellen können, sind empirische Analysen zum Einfluss sozialer (z.B. die Betreuung eigener Kinder, Pflegeaufgaben) und organisationaler Bedingungsfaktoren (z.B. Erwerbstätigkeit, Fahrzeiten zur Praktikumsschule, Zusatzkosten) rar. Daher wurden in diesem Beitrag im Rahmen einer Sekundäranalyse evaluativer Daten Zusammenhänge zwischen dem Belastungserleben von N = 611 Lehramtsstudierenden im Praxissemester an der Universität Paderborn und verschiedenen Bedingungsfaktoren untersucht. Das Belastungserleben wurde vor und nach dem Praxissemester mit Hilfe des Maslach-Burnout-Inventars (MBI-SS) erfasst. Regressionsanalysen ergaben, dass soziale und organisationale Bedingungsfaktoren kaum Unterschiede im Belastungserleben aufklären. Als einzige bedeutende Faktoren mit kleinen Effekten erwiesen sich die Fahrzeit zur Praktikumsschule und die Höhe evtl. zusätzlicher Materialkosten. Auch durch Clusteranalysen ermittelte Gruppen von hochbelasteten Studierenden zeichnen sich nicht durch spezifische soziale oder organisationale Bedingungsfaktoren aus.}}, author = {{Vogelsang, Christoph and Brandhorst, André}}, journal = {{Herausforderung Lehrer* Innenbildung-Zeitschrift Zur Konzeption, Gestaltung Und Diskussion}}, keywords = {{Praxissemester, Belastung, Burnout, Lehramtsstudium, soziale Situation}}, number = {{1}}, title = {{{Schulpraktikum zwischen Kind und Nebenjob? Einfluss von sozialen und organisationalen Bedingungsfaktoren auf das Belastungserleben Lehramtsstudierender im Praxissemester}}}, doi = {{10.11576/HLZ-5818}}, volume = {{6}}, year = {{2023}}, } @inbook{47059, author = {{Weigelt, Matthias and Krause, Daniel and Güldenpenning, Iris}}, booktitle = {{Sport and Exercise Psychology}}, editor = {{Schüler, J. and Wegner, M. and Plessner, H. and Eklund, R. C. }}, isbn = {{9783031039201}}, pages = {{41--70}}, publisher = {{Springer}}, title = {{{Learning and Memory in Sports}}}, doi = {{10.1007/978-3-031-03921-8_3}}, year = {{2023}}, } @article{47155, abstract = {{»Über Geld spricht man nicht.« Diese Benimmregel erweist sich beim Blick in die Ver- gangenheit als Illusion. Keineswegs war Geld grundsätzlich ein Tabuthema zwischen- menschlicher Kommunikation. Ganz im Gegenteil: Mit dem Reden über Geld wird dieses mit Bedeutung aufgeladen. Die Autor*innen dieses Themenheftes untersuch en Gelddis- kurse und die Zuschreibungen von Bedeutung an Geld in der internationalen Geschichte.}}, author = {{Schönhärl, Korinna and Schotters, Frederike and Thiemeyer, Guido}}, journal = {{Werkstatt Geschichte}}, keywords = {{Financial History, Discourse Analysis, History of Money}}, title = {{{Editorial}}}, volume = {{88}}, year = {{2023}}, } @misc{47154, abstract = {{»Über Geld spricht man nicht.« Diese Benimmregel erweist sich beim Blick in die Vergangenheit als Illusion. Keineswegs war Geld grundsätzlich ein Tabuthema zwischenmenschlicher Kommunikation. Ganz im Gegenteil: Mit dem Reden über Geld wird dieses mit Bedeutung aufgeladen. Die Autor*innen dieses Themenheftes untersuchen Gelddiskurse und die Zuschreibungen von Bedeutung an Geld in der internationalen Geschichte.}}, booktitle = {{Werkstatt Geschichte}}, editor = {{Schönhärl, Korinna and Schotters, Frederike and Thiemeyer, Guido}}, keywords = {{Financial History, Discourse Analysis, History of Money}}, title = {{{Reden über Geld}}}, volume = {{88}}, year = {{2023}}, } @inproceedings{44694, author = {{Böer, Nils Tobias and Weigelt, Matthias and Kunde, Wilfried and Güldenpenning, Iris}}, booktitle = {{Human Performance – Assessment, Intervention & Analysen. Abstractband der 55. Jahrestagung der Arbeitsgemeinschaft für Sportpsychologie (asp)}}, editor = {{Schott, Nadja and Klotzbier, Thomas and Korbus, Heide and El-Rajab, I. and Holfelder, B. and Park, S-Y.}}, keywords = {{Perception, Action Preparation, Cognition}}, location = {{Stuttgart: Universität Stuttgart}}, pages = {{116--117}}, publisher = {{Universität Stuttgart}}, title = {{{The influence of effort instructions on the production of head fakes in basketball}}}, year = {{2023}}, } @inproceedings{45779, author = {{Böer, Nils Tobias and Weigelt, Matthias and Güldenpenning, Iris}}, booktitle = {{Abstracts of the 65th Conference of Experimental Psychologists (TeaP)}}, editor = {{Merz, Simon and Frings, Christian and Leuchtenberg, Bettina and Moeller, Birte and Mueller, Stefanie and Neumann, Roland and Pastötter, Bernhard and Pingen, Leah and Schui, Gabriel}}, keywords = {{perception, action preparation, movement planning, effort instructions}}, location = {{Trier}}, pages = {{66--67}}, title = {{{The influence of effort instructions on producing head fakes in basketball }}}, doi = {{https://doi.org/10.23668/psycharchives.12945}}, year = {{2023}}, } @inproceedings{46813, abstract = {{Modelling of dynamic systems plays an important role in many engineering disciplines. Two different approaches are physical modelling and data‐driven modelling, both of which have their respective advantages and disadvantages. By combining these two approaches, hybrid models can be created in which the respective disadvantages are mitigated, with discrepancy models being a particular subclass. Here, the basic system behaviour is described physically, that is, in the form of differential equations. Inaccuracies resulting from insufficient modelling or numerics lead to a discrepancy between the measurements and the model, which can be compensated by a data‐driven error correction term. Since discrepancy methods still require a large amount of measurement data, this paper investigates the extent to which a single discrepancy model can be trained for a physical model with additional parameter dependencies without the need for retraining. As an example, a damped electromagnetic oscillating circuit is used. The physical model is realised by a differential equation describing the electric current, considering only inductance and capacitance; dissipation due to resistance is neglected. This creates a discrepancy between measurement and model, which is corrected by a data‐driven model. In the experiments, the inductance and the capacity are varied. It is found that the same data‐driven model can only be used if additional parametric dependencies in the data‐driven term are considered as well.}}, author = {{Wohlleben, Meike Claudia and Muth, Lars and Peitz, Sebastian and Sextro, Walter}}, booktitle = {{Proceedings in Applied Mathematics and Mechanics}}, issn = {{1617-7061}}, keywords = {{Electrical and Electronic Engineering, Atomic and Molecular Physics, and Optics}}, publisher = {{Wiley}}, title = {{{Transferability of a discrepancy model for the dynamics of electromagnetic oscillating circuits}}}, doi = {{10.1002/pamm.202300039}}, year = {{2023}}, } @article{44312, abstract = {{Zusammenfassung Aufgrund aktueller Transformationsprozesse kommt der automatisierten und ressourceneffizienten Fertigung hochfester Leichtbauteile eine steigende Bedeutung zu, beispielsweise im Flugzeug- und Fahrzeugbau. Für kleine Losgrößen bietet sich hier insbesondere das Fertigungsverfahren des Drückwalzens an. Der konventionelle, industriell genutzte Drückwalzprozess stößt allerdings aufgrund der Prozesskomplexität hinsichtlich der Reproduzierbarkeit an seine Grenzen. Dies wird in der Praxis teilweise durch personengebundenes Erfahrungswissen kompensiert. Auch ist es nicht möglich, Bauteileigenschaften definiert einzustellen. Aus diesem Grund bietet der Einsatz einer neuartigen Eigenschaftsregelung Chancen zur Weiterentwicklung des Fertigungsprozesses und die Möglichkeit zur Prozessautomatisierung. Hier werden die Werkzeugbahnen abhängig einer Online-Eigenschaftsmessung über eine zusätzliche Reglerkaskade manipuliert. Die Entwicklung einer solchen Eigenschaftsregelung erfordert den Einsatz geeigneter, modellbasierter Entwurfsmethoden. In diesem Beitrag wird daher ein regelungstechnisches Systemmodell für das Drückwalzen metastabiler austenitischer Edelstähle vorgestellt. Das Simulationsmodell weist aufgrund seiner Echtzeitfähigkeit neben dem Einsatz als reines Entwurfsmodell weitere Nutzungsmöglichkeiten z.B. in Beobachtern auf und grenzt sich somit von domänenspezifischen Simulationstools wie der FEM ab.}}, author = {{Kersting, Lukas and Arian, Bahman and Rozo Vasquez, Julian and Trächtler, Ansgar and Homberg, Werner and Walther, Frank}}, issn = {{0178-2312}}, journal = {{at - Automatisierungstechnik}}, keywords = {{Electrical and Electronic Engineering, Computer Science Applications, Control and Systems Engineering}}, number = {{1}}, pages = {{68--81}}, publisher = {{Walter de Gruyter GmbH}}, title = {{{Echtzeitfähige Modellierung eines innovativen Drückwalzprozesses für die eigenschaftsgeregelte Bauteilfertigung}}}, doi = {{10.1515/auto-2022-0106}}, volume = {{71}}, year = {{2023}}, }