@inbook{61537, author = {{Schloots, Franziska Margarete}}, booktitle = {{Virtuelles Essen- Interdisziplinäre Perspektiven auf Ernährungspraktiken im digitalen Zeitalter}}, editor = {{Jürgens, Jane Lia and Lewandowski, Kira and Aßmann, Sandra}}, isbn = {{978-3-8394-7633-8}}, keywords = {{Selbstvermessung, Wearables, Diet Tracking, Quantifizierung}}, pages = {{225--251}}, publisher = {{transcript Verlag}}, title = {{{Essen nach Zahlen - Die Quantifizierung von Ernährung im Alltag}}}, doi = {{10.14361/9783839476338}}, year = {{2025}}, } @article{61279, abstract = {{Spin waves represent an important class of low-energy excitations in magnetic solids, which influence the thermodynamic properties and play a major role in technical applications, such as spintronics or magnetic data storage. Despite the enormous advances of ab initio simulations in materials science, quantitative calculations of spin-wave spectra still pose a significant challenge, because the collective nature of the spin dynamics requires an accurate treatment of the Coulomb interaction between the electrons. As a consequence, simple lattice models like the Heisenberg Hamiltonian are still widespread in practical investigations, but modern techniques like time-dependent density-functional theory or many-body perturbation theory also open a route to material-specific spin-wave calculations from first principles. Although both are in principle exact, actual implementations necessarily employ approximations for electronic exchange and correlation as well as additional numerical simplifications. In this review, we recapitulate the theoretical foundations of ab initio spin-wave calculations and analyze the common approximations that underlie present implementations. In addition, we survey the available results for spin-wave dispersions of various magnetic materials and compare the performance of different computational approaches. In this way, we provide an overview of the present state of the art and identify directions for further developments.}}, author = {{Neugum, Michael and Schindlmayr, Arno}}, issn = {{1996-1944}}, journal = {{Materials}}, number = {{18}}, publisher = {{MDPI}}, title = {{{Ab initio calculations of spin waves: A review of theoretical approaches and applications}}}, doi = {{10.3390/ma18184431}}, volume = {{18}}, year = {{2025}}, } @article{60959, abstract = {{Miller's rule originated as an empirical relation between the nonlinear and linear optical coefficients of materials. It is now accepted as a useful tool for guiding experiments and computational materials discovery, but its theoretical foundation had long been limited to a derivation for the classical Lorentz model with a weak anharmonic perturbation. Recently, we developed a mathematical framework which enabled us to prove that Miller's rule is equally valid for quantum anharmonic oscillators, despite different dynamics due to zero-point fluctuations and further quantum-mechanical effects. However, our previous derivation applied only to one-dimensional oscillators and to the special case of second- and third-harmonic generation in a monochromatic electric field. Here we extend the proof to three-dimensional quantum anharmonic oscillators and also treat all orders of the nonlinear response to an arbitrary multi-frequency field. This makes the results applicable to a much larger range of physical systems and nonlinear optical processes. The obtained generalized Miller formulae rigorously express all tensor elements of the frequency-dependent nonlinear susceptibilities in terms of the linear susceptibility and thus allow a computationally inexpensive quantitative prediction of arbitrary parametric frequency-mixing processes from a small initial dataset.}}, author = {{Meyer, Maximilian Tim and Schindlmayr, Arno}}, issn = {{2673-8716}}, journal = {{Dynamics}}, number = {{3}}, publisher = {{MDPI}}, title = {{{Generalized Miller formulae for quantum anharmonic oscillators}}}, doi = {{10.3390/dynamics5030034}}, volume = {{5}}, year = {{2025}}, } @misc{61787, author = {{Hälterlein, Jens}}, booktitle = {{NETZPOLITIK.ORG}}, title = {{{KI im Krieg. „Wir brauchen mehr kritische Debatten und zivilgesellschaftliches Engagement“}}}, year = {{2025}}, } @article{57472, abstract = {{In this paper we introduce, in a Hilbert space setting, a second order dynamical system with asymptotically vanishing damping and vanishing Tikhonov regularization that approaches a multiobjective optimization problem with convex and differentiable components of the objective function. Trajectory solutions are shown to exist in finite dimensions. We prove fast convergence of the function values, quantified in terms of a merit function. Based on the regime considered, we establish both weak and, in some cases, strong convergence of trajectory solutions toward a weak Pareto optimal solution. To achieve this, we apply Tikhonov regularization individually to each component of the objective function. This work extends results from single objective convex optimization into the multiobjective setting.}}, author = {{Bot, Radu Ioan and Sonntag, Konstantin}}, journal = {{Journal of Mathematical Analysis and Applications}}, keywords = {{Pareto optimization, Lyapunov analysis, gradient-like dynamical systems, inertial dynamics, asymptotic vanishing damping, Tikhonov regularization, strong convergence}}, title = {{{Inertial dynamics with vanishing Tikhonov regularization for multobjective optimization}}}, year = {{2025}}, } @article{61860, author = {{Kunert, Irene Dorothea}}, journal = {{PhiN Beiheft 40: Verdichtung und Auffächerung. (Übersetzte) Literatur zwischen Präsenz und Virtualität}}, pages = {{136 -- 154}}, title = {{{Auffächerung im Spiegel der Übersetzung und darüber hinaus: La Grande Peur dans la montagne von Charles Ferdinand Ramuz und die beiden deutschen Übersetzungen dieses Romans}}}, year = {{2025}}, } @misc{59615, author = {{Schmitt, Martin}}, booktitle = {{HSozKult}}, keywords = {{Rechenzentren, Geschichte, Umweltgeschichte, Nachhaltigkeit, Supercomputing, Technikgeschichte}}, title = {{{Geschichte und Umwelt von Rechenzentren; Rezension zu: Dommann, Monika; Rickli, Hannes; Stadler, Max (Hrsg.): Data Centers. Edges of a Wired Nation, Zürich 2020; Gugerli, David; Wichum, Ricky: An den Grenzen der Berechenbarkeit. Supercomputing in Stuttgart, Zürich 2021}}}, year = {{2025}}, } @article{62016, author = {{Hälterlein, Jens}}, journal = {{European Journal of International Security}}, title = {{{The more-than-human biopolitics of swarming – complexity, emergence, and control in military robotics}}}, doi = {{10.1017/eis.2025.10023}}, year = {{2025}}, } @article{61762, abstract = {{Abstract In punch-bending, products such as brackets, electronic contacts or spring elements are produced from wire-shaped semi-finished products using separation processes and several successive forming processes. Within the multi-stage straightening and bending processes, cross-stage and quantity-dependent effects have a significant influence on the quality of the end product. In order to optimize the punch-bending process with regard to the resulting component deviations and waste rate, this article presents the concept of a digital twin for an innovative hybrid model of a multi-stage punch-bending process. To ensure efficient development and implementation of the digital twin, the graphical modeling notation DSL4DPiFS is used for additional support. It makes it possible to derive the required interfaces of the Asset Administration Shell of the hybrid data-driven model.}}, author = {{Peters, Henning and Mazur, Andreas and Pandey, Ankit Kumar and Trächtler, Ansgar and Hammer, Barbara and Homberg, Werner}}, issn = {{0178-2312}}, journal = {{at - Automatisierungstechnik}}, number = {{3}}, pages = {{173--184}}, publisher = {{Walter de Gruyter GmbH}}, title = {{{Development of a digital twin for data-driven modeling of punch-bending processes using a graphical modeling notation}}}, doi = {{10.1515/auto-2024-0112}}, volume = {{73}}, year = {{2025}}, } @inproceedings{61763, abstract = {{Abstract. Within the punch-bending process semi-finished products of strip or wire material are formed and punched in several subsequent steps into a finished product like brackets, mounts, contacts or spring elements. In the context of those multi-stage straightening and bending processes, cross-stage and quantity-dependent effects significantly leads to undesired component deviations. To optimize the punch-bending process with regard to these component deviations and thus the waste rate, the concept of a hybrid data-driven model is presented. To automatically acquire and process this hybrid data while also enable the usage by multiple clients, a digital twin has to be developed. In this paper the communication infrastructure between the punch-bending system and the digital twin is presented, using the Asset Administration Shell as specification. This automated communication is validated using exemplary data from the punch-bending system.}}, author = {{Peters, Henning and Mazur, Andreas and Trächtler, Ansgar and Hammer, Barbara}}, booktitle = {{Materials Research Proceedings}}, issn = {{2474-395X}}, publisher = {{Materials Research Forum LLC}}, title = {{{Integration of a digital twin for data-driven modeling of punch-bending processes using the asset administration shell}}}, doi = {{10.21741/9781644903599-166}}, volume = {{54}}, year = {{2025}}, } @article{61761, abstract = {{Abstract Data-driven methods are increasingly utilized in metal forming processes for monitoring and quality optimization. An adapted modeling notation DSL4DPiFS for forming processes is presented to model hardware, software, and data flow aspects to support the design and analysis of data-driven methods. DSL4DPiFS enables metal forming and automation experts to model field-level information as data sources, and the data sinks for data analysis. The notation was adapted to the requirements of selected metal forming processes and evaluated in three case studies.}}, author = {{Vogel-Heuser, Birgit and Zhang, Mingxi and Krüger, Marius and Vicaria, Alejandra and Gardill, Markus and Jiang, Yuyao and Trächtler, Ansgar and Peters, Henning and Liewald, Mathias and Schenek, Adrian and Heinzelmann, Pascal and Weyrich, Michael}}, issn = {{0178-2312}}, journal = {{at - Automatisierungstechnik}}, number = {{4}}, pages = {{232--250}}, publisher = {{Walter de Gruyter GmbH}}, title = {{{DSL4DPiFS – a graphical notation to model data pipeline deployment in forming systems}}}, doi = {{10.1515/auto-2024-0114}}, volume = {{73}}, year = {{2025}}, } @inbook{61765, author = {{Mazur, Andreas and Peters, Henning and Artelt, André and Koller, Lukas and Hartmann, Christoph and Trächtler, Ansgar and Hammer, Barbara}}, booktitle = {{Lecture Notes in Computer Science}}, isbn = {{9783032045546}}, issn = {{0302-9743}}, publisher = {{Springer Nature Switzerland}}, title = {{{Studying the Generalization Behavior of Surrogate Models for Punch-Bending by Generating Plausible Counterfactuals}}}, doi = {{10.1007/978-3-032-04555-3_16}}, year = {{2025}}, } @inproceedings{59907, abstract = {{Abstract. Flow forming is recognized for its precision in producing rotationally symmetric components, but the use of metastable austenitic stainless steel (AISI 304L) introduces challenges due to uncontrolled strain-induced α’ martensite formation. Variations in factors such as eccentricity and batch inconsistencies lead to unpredictable microstructural profiles, limiting reproducibility [1,2]. This study addresses these issues by incorporating thermal actuators for cryogenic cooling and induction heating to regulate forming temperatures, enabling control of the α’-martensite content. Experimental investigations demonstrate that local tempering during thermomechanical reverse flow forming produces discernible variations in microstructure, affecting mechanical and magnetic properties [3]. Controlled local adjustments of α’-martensite content allow for customization of properties in seamless tubes, advancing manufacturing capabilities for complex, defect-free components. The results presented demonstrate promising strategies for implementation within the context of closed-loop property control in flow forming.}}, author = {{Arian, Bahman and Homberg, Werner and Kersting, Lukas and Trächtler, Ansgar and Rozo Vasquez, Julian and Walther, Frank}}, booktitle = {{Materials Research Proceedings}}, editor = {{Carlone, Pierpaolo and Filice, Luigino and Umbrello, Domenico}}, issn = {{2474-395X}}, keywords = {{Flow Forming, Thermomechanical Forming, α’-Martensite, Property Control}}, location = {{Paestum, Italy}}, publisher = {{Materials Research Forum LLC}}, title = {{{Advanced thermomechanical flow forming: A novel approach to α’-martensite control for enhanced material properties}}}, doi = {{10.21741/9781644903599-127}}, volume = {{54}}, year = {{2025}}, } @article{62024, abstract = {{Abstract This paper presents a characterization of the microstructural evolution and its correlation with the magnetic structure due to flow forming of semi-finished tubes of austenitic stainless steel AISI 304L. The plastic deformation triggers a phase transformation of the metastable austenite into α’-martensite. Depending on the combination of production parameters, different fractions of strain-induced α’-martensite were measured by means non-destructive micromagnetic techniques and correlated with the evolution of hardness and the microstructure using electron backscatter diffraction analyses. The magneto-optical Kerr effect analysis was used as a tool to perform a qualitative analysis of the evolution of the magnetic domain structure correlated with the formation of α’-martensite. An analysis of these data allowed to derive surface magnetization hysteresis loops that were compared with integral hysteresis loops of the specimens. It was proven by both methods that the formation of martensite increases the magnetic energy and the spontaneous magnetization of the specimens. The results of this investigation contribute to a better understanding of micromagnetic sensors to monitor and control the formation of α’-martensite in a flow forming. Furthermore, various techniques have demonstrated the evolution of the magnetic properties of the material, which can be applied in applications for invisible coding of workpieces.}}, author = {{Rozo Vasquez, Julian and Tappe, Jan and Arian, Bahman and Kersting, Lukas and Homberg, Werner and Trächtler, Ansgar and Walther, Frank}}, issn = {{2195-8599}}, journal = {{Practical Metallography}}, number = {{9-10}}, pages = {{617--633}}, publisher = {{Walter de Gruyter GmbH}}, title = {{{Magneto-optical Kerr effect analysis of strain-induced martensite formation during flow forming of metastable austenitic steel AISI 304L}}}, doi = {{10.1515/pm-2025-0059}}, volume = {{62}}, year = {{2025}}, } @inproceedings{62022, abstract = {{Abstract. The incremental flow forming process features a large number of process parameter combinations that can be varied from pass to pass or during a pass. In the future however, a more efficient utilization of this large number of process parameter combinations and a compensation of process disturbances could be required. This is due to a rising demand for increasing the part complexity, e.g. by graded property structures or a more complex geometry. In this context, innovative approaches like closed-loop property control and optimal control are advantageous, but require fast process models of flow forming that are not state of the art. This paper thus proposes a new modelling approach of multi-pass flow forming especially taking the transfer behavior between process parameters and wall thickness evolution from pass to pass into focus. A hybrid modelling approach is developed that combines knowledge about the incremental process character with empirical data regression to a basic analytic relation. The basic relation is further extended by a multi-layer neural network to enhance the overall model accuracy. This hybrid modelling approach is finally validated using experimental data. Thus, it is shown that a suitable model structure was found in context of a future closed-loop control or optimal control for multi-pass flow forming.}}, author = {{Kersting, Lukas and Gunasagran, Sharin Kumar and Arian, Bahman and Rozo Vaszquez, Julian and Trächtler, Ansgar and Homberg, Werner and Walther, Frank}}, booktitle = {{Materials Research Proceedings}}, issn = {{2474-395X}}, publisher = {{Materials Research Forum LLC}}, title = {{{Real-time modelling of incremental multi-pass flow forming by a hybrid, data-based model}}}, doi = {{10.21741/9781644903599-140}}, volume = {{54}}, year = {{2025}}, } @article{62023, abstract = {{Zusammenfassung Die Eigenschaftsregelung mit einer online-Messung der Bauteileigenschaften ist ein in der Umformtechnik viel diskutiertes, aber kaum validiertes Konzept, um den Automatisierungsgrad bei der Bauteilfertigung weiter zu erhöhen. Dieser Artikel soll helfen, die Lücke beispielhaft für den Fertigungsprozess des Drückwalzens metastabiler Austenite zu schließen. Der metastabile austenitische Edelstahl ändert hierbei während der Verformung seinen α′-Martensitgehalt und damit verbunden die magnetischen Eigenschaften. Deshalb soll über die Regelung das definierte Einstellen des α′-Martensitgehaltes möglich werden. Im Rahmen des vorliegenden Artikels wird gezeigt, wie mittels des modellbasierten Entwurfs die Eigenschaftsregelung ausgelegt und parametriert werden kann. Zudem beinhaltet der Artikel experimentelle Validierungsergebnisse der zuvor entworfenen Eigenschaftsregelung.}}, 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}}, number = {{7}}, pages = {{527--540}}, publisher = {{Walter de Gruyter GmbH}}, title = {{{Modellbasierter Entwurf und Validierung einer Eigenschaftsregelung für das Drückwalzen metastabiler Austenite}}}, doi = {{10.1515/auto-2024-0127}}, volume = {{73}}, year = {{2025}}, } @article{62021, author = {{Kersting, Lukas and Arian, Bahman and Rozo Vasquez, Julian and Trächtler, Ansgar and Homberg, Werner and Walther, Frank}}, issn = {{2405-8963}}, journal = {{IFAC-PapersOnLine}}, number = {{1}}, pages = {{109--114}}, publisher = {{Elsevier BV}}, title = {{{State-space modelling approach for control and observer design in property-controlled reverse flow forming}}}, doi = {{10.1016/j.ifacol.2025.03.020}}, volume = {{59}}, year = {{2025}}, } @unpublished{61999, author = {{Münzmay, Andreas}}, pages = {{24}}, title = {{{Beethovens Eigenbearbeitungen und digitale Heuristik. Erkundungen mit den synoptischen Doppeleditionen und Analysewerkzeugen des Projekts Beethovens Werkstatt}}}, year = {{2025}}, } @article{62045, author = {{Naumann, Marius and Henne, Kevin and Ostermann, Moritz and Schlosser, Florian and Meschede, Henning}}, journal = {{Procedia CIRP}}, location = {{Manchester}}, pages = {{1351--1358}}, publisher = {{Elsevier}}, title = {{{Modular Energy Demand Modeling of Manufacturing Processes for Energy Efficiency Improvement}}}, doi = {{doi.org/10.1016/j.procir.2025.08.001}}, volume = {{135}}, year = {{2025}}, } @article{62064, abstract = {{SYCL is an open standard for targeting heterogeneous hardware from C++. In this work, we evaluate a SYCL implementation for a discontinuous Galerkin discretization of the 2D shallow water equations targeting CPUs, GPUs, and also FPGAs. The discretization uses polynomial orders zero to two on unstructured triangular meshes. Separating memory accesses from the numerical code allow us to optimize data accesses for the target architecture. A performance analysis shows good portability across x86 and ARM CPUs, GPUs from different vendors, and even two variants of Intel Stratix 10 FPGAs. Measuring the energy to solution shows that GPUs yield an up to 10x higher energy efficiency in terms of degrees of freedom per joule compared to CPUs. With custom designed caches, FPGAs offer a meaningful complement to the other architectures with particularly good computational performance on smaller meshes. FPGAs with High Bandwidth Memory are less affected by bandwidth issues and have similar energy efficiency as latest generation CPUs.}}, author = {{Büttner, Markus and Alt, Christoph and Kenter, Tobias and Köstler, Harald and Plessl, Christian and Aizinger, Vadym}}, issn = {{1573-0484}}, journal = {{The Journal of Supercomputing}}, number = {{6}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{Analyzing performance portability for a SYCL implementation of the 2D shallow water equations}}}, doi = {{10.1007/s11227-025-07063-7}}, volume = {{81}}, year = {{2025}}, }