TY - CONF AU - Schryen, Guido AU - Marrone, Mauricio AU - Yang, Jiaqi ID - 47427 T2 - Proceedings of the 57th Hawaii International Conference on System Science (HICSS 2024) TI - Adopting Generative AI for Literature Reviews: An Epistemological Perspective ER - TY - CONF AU - Betke, Hans AU - Sperling, Martina AU - Schryen, Guido AU - Sackmann, Stefan ID - 47429 T2 - Proceedings of the 57th Hawaii International Conference on System Science (HICSS 2024) TI - A Design Theory for Spontaneous Volunteer Coordination Systems in Disaster Response ER - TY - JOUR AU - Weich, Tobias AU - Guedes Bonthonneau, Yannick AU - Guillarmou, Colin ID - 32097 JF - Journal of Differential Geometry (to appear) -- arXiv:2103.12127 TI - SRB Measures of Anosov Actions ER - TY - JOUR AB - When it comes to NP, its natural definition, its wide applicability across scientific disciplines, and its timeless relevance, the writing is on the wall: There can be only one. Quantum NP, on the other hand, is clearly the apple that fell far from the tree of NP. Two decades since the first definitions of quantum NP started rolling in, quantum complexity theorists face a stark reality: There's QMA, QCMA, QMA1, QMA(2), StoqMA, and NQP. In this article aimed at a general theoretical computer science audience, I survey these various definitions of quantum NP, their strengths and weaknesses, and why most of them, for better or worse, actually appear to fit naturally into the complexity zoo. AU - Gharibian, Sevag ID - 48544 IS - 4 JF - ACM SIGACT News TI - Guest Column: The 7 faces of quantum NP VL - 54 ER - TY - JOUR AU - Schryen, Guido ID - 50301 JF - Journal of Parallel and Distributed Computing TI - Speedup and efficiency of computational parallelization: A unifying approach and asymptotic analysis ER - TY - JOUR AB - We show how to learn discrete field theories from observational data of fields on a space-time lattice. For this, we train a neural network model of a discrete Lagrangian density such that the discrete Euler--Lagrange equations are consistent with the given training data. We, thus, obtain a structure-preserving machine learning architecture. Lagrangian densities are not uniquely defined by the solutions of a field theory. We introduce a technique to derive regularisers for the training process which optimise numerical regularity of the discrete field theory. Minimisation of the regularisers guarantees that close to the training data the discrete field theory behaves robust and efficient when used in numerical simulations. Further, we show how to identify structurally simple solutions of the underlying continuous field theory such as travelling waves. This is possible even when travelling waves are not present in the training data. This is compared to data-driven model order reduction based approaches, which struggle to identify suitable latent spaces containing structurally simple solutions when these are not present in the training data. Ideas are demonstrated on examples based on the wave equation and the Schrödinger equation. AU - Offen, Christian AU - Ober-Blöbaum, Sina ID - 46469 IS - 1 JF - Chaos SN - 1054-1500 TI - Learning of discrete models of variational PDEs from data VL - 34 ER - TY - JOUR AB - Broadband coherent anti-Stokes Raman scattering (BCARS) is a powerful spectroscopy method combining high signal intensity with spectral sensitivity, enabling rapid imaging of heterogeneous samples in biomedical research and, more recently, in crystalline materials. However, BCARS encounters spectral distortion due to a setup-dependent non-resonant background (NRB). This study assesses BCARS reproducibility through a round robin experiment using two distinct BCARS setups and crystalline materials with varying structural complexity, including diamond, 6H-SiC, KDP, and KTP. The analysis compares setup-specific NRB correction procedures, detected and NRB-removed spectra, and mode assignment. We determine the influence of BCARS setup parameters like pump wavelength, pulse width, and detection geometry and provide a practical guide for optimizing BCARS setups for solid-state applications. AU - Hempel, Franz AU - Vernuccio, Federico AU - König, Lukas AU - Buschbeck, Robin AU - Rüsing, Michael AU - Cerullo, Giulio AU - Polli, Dario AU - Eng, Lukas M. ID - 49652 IS - 1 JF - Applied Optics KW - Atomic and Molecular Physics KW - and Optics KW - Engineering (miscellaneous) KW - Electrical and Electronic Engineering SN - 1559-128X TI - Comparing transmission- and epi-BCARS: a round robin on solid-state materials VL - 63 ER - TY - JOUR AU - Domenik Ackermann ID - 50101 JF - Quick And Easy Journal Title TI - New Quick And Easy Publication - Will be edited by LibreCat team ER - TY - JOUR AU - Domenik Ackermann ID - 50099 JF - Quick And Easy Journal Title TI - New Quick And Easy Publication - Will be edited by LibreCat team ER - TY - CHAP AU - Prediger, Susanne AU - Wessel, Lena ED - Efing, Christian ED - Kalkavan-Aydin, Zeynep ID - 50554 SN - 978-3-11-074544-3 T2 - Berufs-und Fachsprache Deutsch in Wissenschaft und Praxis TI - 31 Sprachbildung im berufsbezogenen Mathematikunterricht. VL - Band 3 ER - TY - JOUR AU - Huybrechts, Yves AU - Karaca, Resul ID - 49772 JF - Synergies Pays germanophones SN - 1866-5268 TI - BelgienNet – une plateforme pour l’accès aux langues et cultures de la Belgique VL - 16 ER - TY - JOUR AU - Moretto, Giordano AU - Schnell, Nicolas AU - Frey, Jonathan AU - Karakaya, Yasin AU - Amstutz, Alois AU - Diehl, Moritz AU - Kasper, Tina AU - Onder, Christopher ID - 50841 JF - Control Engineering Practice TI - Fast model-based calibration of multiple injections for a CI engine using nonlinear optimal control VL - 145 ER - TY - JOUR AB - Ferroelectric domain wall (DW) conductivity (DWC) can be attributed to two separate mechanisms: (a) the injection/ejection of charge carriers across the Schottky barrier formed at the (metal-)electrode-DW junction and (b) the transport of those charge carriers along the DW. Current-voltage (I-U) characteristics, recorded at variable temperatures from LiNbO3 (LNO) DWs, are clearly able to differentiate between these two contributions. Practically, they allow us to directly quantify the physical parameters relevant to the two mechanisms (a) and (b) mentioned above. These are, for example, the resistance of the DW, the saturation current, the ideality factor, and the Schottky barrier height of the electrode-DW junction. Furthermore, the activation energies needed to initiate the thermally activated electronic transport along the DWs can be extracted. In addition, we show that electronic transport along LNO DWs can be elegantly viewed and interpreted in an adapted semiconductor picture based on a double-diode, double-resistor equivalent-circuit model, the R2D2 model. Finally, our R2D2 model was checked for its universality by successfully fitting the I-U curves of not only z-cut LNO bulk DWs, but equally of z-cut thin-film LNO DWs, and of x-cut thin-film DWs as reported in literature. AU - Zahn, Manuel AU - Beyreuther, Elke AU - Kiseleva, Iuliia AU - Lotfy, Ahmed Samir AU - McCluskey, Conor J. AU - Maguire, Jesi R. AU - Suna, Ahmet AU - Rüsing, Michael AU - Gregg, J. Marty AU - Eng, Lukas M. ID - 51156 IS - 2 JF - Physical Review Applied KW - General Physics and Astronomy SN - 2331-7019 TI - Equivalent-circuit model that quantitatively describes domain-wall conductivity in ferroelectric lithium VL - 21 ER - TY - GEN AB - We rigorously derive novel and sharp finite-data error bounds for highly sample-efficient Extended Dynamic Mode Decomposition (EDMD) for both i.i.d. and ergodic sampling. In particular, we show all results in a very general setting removing most of the typically imposed assumptions such that, among others, discrete- and continuous-time stochastic processes as well as nonlinear partial differential equations are contained in the considered system class. Besides showing an exponential rate for i.i.d. sampling, we prove, to the best of our knowledge, the first superlinear convergence rates for ergodic sampling of deterministic systems. We verify sharpness of the derived error bounds by conducting numerical simulations for highly-complex applications from molecular dynamics and chaotic flame propagation. AU - Philipp, Friedrich M. AU - Schaller, Manuel AU - Boshoff, Septimus AU - Peitz, Sebastian AU - Nüske, Feliks AU - Worthmann, Karl ID - 51160 T2 - arXiv:2402.02494 TI - Extended Dynamic Mode Decomposition: Sharp bounds on the sample efficiency ER - TY - GEN AU - Peckhaus, Volker ED - Zalta, Edward N.. ED - Nodelman, Uri ID - 17740 T2 - The Stanford Encyclopedia of Philosophy, first published Sep 4, 2009, substantive revision Feb 2, 2024 TI - Leibniz’s Influence on 19th Century Logic ER - TY - GEN AU - Schmidt, Rebecca ID - 51301 T2 - SozMethode TI - Automatische Transkriptionssoftware – ein Erfahrungsbericht. ER - TY - JOUR AU - Weich, Tobias AU - Guedes Bonthonneau, Yannick AU - Guillarmou, Colin AU - Hilgert, Joachim ID - 32101 JF - J. Europ. Math. Soc. TI - Ruelle-Taylor resonaces of Anosov actions ER - TY - GEN AU - Hilgert, Joachim ID - 51501 TI - Quantum-Classical Correspondences for Locally Symmetric Spaces ER - TY - JOUR AU - Cui, Tie Jun AU - Zhang, Shuang AU - Alu, Andrea AU - Wegener, Martin AU - Pendry, John AU - Luo, Jie AU - Lai, Yun AU - Wang, Zuojia AU - Lin, Xiao AU - Chen, Hongsheng AU - Chen, Ping AU - Wu, Rui-Xin AU - Yin, Yuhang AU - Zhao, Pengfei AU - Chen, Huanyang AU - Li, Yue AU - Zhou, Ziheng AU - Engheta, Nader AU - Asadchy, V. S. AU - Simovski, Constantin AU - Tretyakov, Sergei A AU - Yang, Biao AU - Campbell, Sawyer D. AU - Hao, Yang AU - Werner, Douglas H AU - Sun, Shulin AU - Zhou, Lei AU - Xu, Su AU - Sun, Hong-Bo AU - Zhou, Zhou AU - Li, Zile AU - Zheng, Guoxing AU - Chen, Xianzhong AU - Li, Tao AU - Zhu, Shi-Ning AU - Zhou, Junxiao AU - Zhao, Junxiang AU - Liu, Zhaowei AU - Zhang, Yuchao AU - Zhang, Qiming AU - Gu, Min AU - Xiao, Shumin AU - Liu, Yongmin AU - Zhang, Xiaoyu AU - Tang, Yutao AU - Li, Guixin AU - Zentgraf, Thomas AU - Koshelev, Kirill AU - Kivshar, Yuri S. AU - Li, Xin AU - Badloe, Trevon AU - Huang, Lingling AU - Rho, Junsuk AU - Wang, Shuming AU - Tsai, Din Ping AU - Bykov, A. Yu. AU - Krasavin, Alexey V AU - Zayats, Anatoly V AU - McDonnell, Cormac AU - Ellenbogen, Tal AU - Luo, Xiangang AU - Pu, Mingbo AU - Garcia-Vidal, Francisco J AU - Liu, Liangliang AU - Li, Zhuo AU - Tang, Wenxuan AU - Ma, Hui Feng AU - Zhang, Jingjing AU - Luo, Yu AU - Zhang, Xuanru AU - Zhang, Hao Chi AU - He, Pei Hang AU - Zhang, Le Peng AU - Wan, Xiang AU - Wu, Haotian AU - Liu, Shuo AU - Jiang, Wei Xiang AU - Zhang, Xin Ge AU - Qiu, Chengwei AU - Ma, Qian AU - Liu, Che AU - Li, Long AU - Han, Jiaqi AU - Li, Lianlin AU - Cotrufo, Michele AU - Caloz, Christophe AU - Deck-Léger, Z.-L. AU - Bahrami, A. AU - Céspedes, O. AU - Galiffi, Emanuele AU - Huidobro, P. A. AU - Cheng, Qiang AU - Dai, Jun Yan AU - Ke, Jun Cheng AU - Zhang, Lei AU - Galdi, Vincenzo AU - Di Renzo, Marco ID - 51519 JF - Journal of Physics: Photonics KW - Electrical and Electronic Engineering KW - Atomic and Molecular Physics KW - and Optics KW - Electronic KW - Optical and Magnetic Materials SN - 2515-7647 TI - Roadmap on electromagnetic metamaterials and metasurfaces ER - TY - GEN AU - Staffel, Florian Lukas ID - 51624 IS - 2 T2 - Sehepunkte TI - Christian Marx: Wegbereiter der Globalisierung. Multinationale Unternehmen der westeuropäischen Chemieindustrie in der Zeit nach dem Boom (1960er-2000er Jahre) (= Nach dem Boom), Göttingen 2023. VL - 24 ER - TY - JOUR AB - We derive efficient algorithms to compute weakly Pareto optimal solutions for smooth, convex and unconstrained multiobjective optimization problems in general Hilbert spaces. To this end, we define a novel inertial gradient-like dynamical system in the multiobjective setting, which trajectories converge weakly to Pareto optimal solutions. Discretization of this system yields an inertial multiobjective algorithm which generates sequences that converge weakly to Pareto optimal solutions. We employ Nesterov acceleration to define an algorithm with an improved convergence rate compared to the plain multiobjective steepest descent method (Algorithm 1). A further improvement in terms of efficiency is achieved by avoiding the solution of a quadratic subproblem to compute a common step direction for all objective functions, which is usually required in first-order methods. Using a different discretization of our inertial gradient-like dynamical system, we obtain an accelerated multiobjective gradient method that does not require the solution of a subproblem in each step (Algorithm 2). While this algorithm does not converge in general, it yields good results on test problems while being faster than standard steepest descent. AU - Sonntag, Konstantin AU - Peitz, Sebastian ID - 46019 JF - Journal of Optimization Theory and Applications TI - Fast Multiobjective Gradient Methods with Nesterov Acceleration via Inertial Gradient-Like Systems ER - TY - GEN AB - The efficient optimization method for locally Lipschitz continuous multiobjective optimization problems from [1] is extended from finite-dimensional problems to general Hilbert spaces. The method iteratively computes Pareto critical points, where in each iteration, an approximation of the subdifferential is computed in an efficient manner and then used to compute a common descent direction for all objective functions. To prove convergence, we present some new optimality results for nonsmooth multiobjective optimization problems in Hilbert spaces. Using these, we can show that every accumulation point of the sequence generated by our algorithm is Pareto critical under common assumptions. Computational efficiency for finding Pareto critical points is numerically demonstrated for multiobjective optimal control of an obstacle problem. AU - Sonntag, Konstantin AU - Gebken, Bennet AU - Müller, Georg AU - Peitz, Sebastian AU - Volkwein, Stefan ID - 51334 T2 - arXiv:2402.06376 TI - A Descent Method for Nonsmooth Multiobjective Optimization in Hilbert Spaces ER - TY - GEN AB - Estimating the infection risks in indoor environments comprises the assessment of the behavior of virus-laden aerosols, i.e. spreading, mixing, removal by air purifiers etc. A promising experimental approach is based on using non-hazardous surrogate aerosols of similar size, e.g. salt particles, to mimic the virus aerosol behavior. This manuscript addresses the issue how a successful transfer of such experiments can be accomplished. Corresponding experiments in two very different environments, a large community hall and a seminar room, with optional use of air purifiers in various constellations were conducted. While high particle concentrations are advantageous in terms of avoiding influence of background aerosol concentrations, it is shown that appropriate consideration of aggregation and settling are vital to theoretically describe the experimentally determined course of particle concentrations. A corresponding model equation for a well-mixed situation is derived and the required parameters are thoroughly determined in separate experiments independently. It is demonstrated that clean air delivery rates (CADR) of air purifiers determined with this approach may differ substantially from common approaches not explicitly taking into account aggregation. AU - Beimdiek, Janis AU - Schmid, Hans-Joachim ID - 51731 KW - surrogate aerosols KW - indoor air cleaners KW - ultra-fine particles KW - COVID-19 KW - test method KW - field experiments: clean air delivery rate T2 - Atmosphere TI - Evaluation of Surrogate Aerosol Experiments to Predict Spreading and Removal of Virus-Laden Aerosols ER - TY - CHAP AU - Richter, Susanne ED - Kieslinger, Daniel ED - Owsianowski, Judith ID - 51790 SN - 978-3-7841-3666-0 T2 - Inklusiver Kinderschutz – Anforderungen, Herausforderungen, Perspektiven TI - Herausforderungen in der inklusiven Mädchenarbeit: Begleitforschung der „Inklusiven anonymen Zuflucht“ des Mädchenhaus Bielefeld e.V. ER - TY - JOUR AB - We present a convolutional framework which significantly reduces the complexity and thus, the computational effort for distributed reinforcement learning control of dynamical systems governed by partial differential equations (PDEs). Exploiting translational equivariances, the high-dimensional distributed control problem can be transformed into a multi-agent control problem with many identical, uncoupled agents. Furthermore, using the fact that information is transported with finite velocity in many cases, the dimension of the agents’ environment can be drastically reduced using a convolution operation over the state space of the PDE, by which we effectively tackle the curse of dimensionality otherwise present in deep reinforcement learning. In this setting, the complexity can be flexibly adjusted via the kernel width or by using a stride greater than one (meaning that we do not place an actuator at each sensor location). Moreover, scaling from smaller to larger domains – or the transfer between different domains – becomes a straightforward task requiring little effort. We demonstrate the performance of the proposed framework using several PDE examples with increasing complexity, where stabilization is achieved by training a low-dimensional deep deterministic policy gradient agent using minimal computing resources. AU - Peitz, Sebastian AU - Stenner, Jan AU - Chidananda, Vikas AU - Wallscheid, Oliver AU - Brunton, Steven L. AU - Taira, Kunihiko ID - 40171 JF - Physica D: Nonlinear Phenomena TI - Distributed Control of Partial Differential Equations Using Convolutional Reinforcement Learning VL - 461 ER - TY - JOUR AB - athematische Kompetenzen digital zu fördern und digitale Kompetenzen mathematisch zu fördern – dies ist eine Forderung der neuen Bildungsstandards mit Blick auf eine Bildung in der digitalen Welt. Gerade das Potenzial digitaler Medien für das fachliche Lernen wurde in vielen Studien bestätigt. Eine sinnvoll gestaltete Einbettung digitaler Medien bietet die Chance, allen fünf Prinzipien eines guten Unterrichts gerecht zu werden: Verstehensorientierung, Durchgängigkeit, kognitive Aktivierung, Lernendenorientierung & Adaptivität und Kommunikationsförderung. Die flächendeckende Nutzung digitaler Medien etabliert sich bislang nur zögerlich. Aber wie können wir Lehrkräfte stärken, digitale Medien sinnvoll einzusetzen? Wir möchten hier die Bandbreite der Möglichkeiten an Beispielen verdeutlichen, ihren Einsatz motivieren und Wege für einen guten Unterricht aufzeigen. AU - Barzel, Bärbel AU - Greefrath, Gilbert AU - Nagel, Mareike AU - Hoffmann, Max ID - 51841 JF - mathematik lehren TI - Digitalisierung als Chance für alle Prinzipien guten Unterrichts VL - 242 ER - TY - GEN AU - Riedl, Lars ID - 50728 SN - 978-3-8376-6682 T2 - Kölner Zeitschrift für Soziologie und Sozialpsychologie TI - Soziologie des Flitzers ER - TY - JOUR AB - In der Professionalisierung von Lehrkräften ist die Selbst-reflexion eine wesentliche Voraussetzung, da sie zentral für die Weiterentwicklung der eigenen Kompetenzen ist. Daraus ergibt sich die Notwendigkeit, bereits in der ersten Phase der Lehrkräftebildung die Selbstreflexion und die Weiterentwicklungsorientierung zu fördern. Hierzu sind auf Grund des sozialen Settings gezielte reflexionsorientierte Workshops chancenreich. Um die Effekte von reflexionsorientierten Workshops und dabei den Zusammenhang zwischen der Selbst-reflexion und der Weiterentwicklungsorientierung zu überprüfen, wurden anhand einer Stichprobe von N = 646 Lehramtsstudierenden die Entwicklung der Selbst-reflexion und Weiterentwicklungsorientierung beim Besuch von Workshops zu überfachlichen Kompetenzen untersucht. Die Datenerhebung erfolgte vor, direkt nach und erneut vier bis sechs Wochen nach den reflexionsorientierten Workshops mittels eines Fragebogens. Durch Varianzanalysen können in Bezug auf die Selbst-reflexion direkt nach den Workshops signifikante Effekte sowie eine konstante Ausprägung vier bis sechs Wochen später nachgewiesen werden. Weiterhin konnte ein signifikanter Anstieg bei der Weiterentwicklungsorientierung über die drei Messzeitpunkte verzeichnet werden. Ebenso zeigte sich ein positiver Effekt der Selbstreflexion auf den Anstieg der Weiterentwicklungsorientierung. AU - Kleine, Sabrina M AU - Sohlau, Sylvia AU - Seifert, Andreas AU - Buhl, Heike M. ID - 52328 IS - 1 JF - Herausforderung Lehrer*innenbildung - Zeitschrift zur Konzeption, Gestaltung und Diskussion TI - Förderung der Selbstreflexion und Weiterentwicklungsorientierung durch reflexionsorientierte Workshops im Lehramtsstudium VL - 7 ER - TY - JOUR AU - Beimdiek, Janis AU - Schmid, Hans-Joachim ID - 52357 IS - 3 JF - Atmosphere KW - surrogate aerosols KW - indoor air cleaners KW - ultra-fine particles KW - COVID-19 KW - test method KW - field experiments: clean air delivery rate SN - 2073-4433 TI - Evaluation of Surrogate Aerosol Experiments to Predict Spreading and Removal of Virus-Laden Aerosols VL - 15 ER - TY - JOUR AU - Al-Lami, Abbas J.S. AU - Kenig, Eugeny Y. ID - 51122 JF - Case Studies in Thermal Engineering KW - Fluid Flow and Transfer Processes KW - Engineering (miscellaneous) SN - 2214-157X TI - New pressure drop and heat transfer correlations for turbulent forced convection in internally channeled tube heat exchanger ducts ER - TY - GEN AU - Breckner, Anne ID - 52465 TI - All you need is love… Gedanken für das neue Jahr ER - TY - JOUR AU - Kundisch, Heike AU - Kremer, H.-Hugo AU - Otto, Franziska ID - 52503 IS - 3 JF - QfI - Qualifizierung für Inklusion Online-Zeitschrift zur Forschung über Aus-, Fort- und Weiterbildung pädagogischer Fachkräfte TI - Selbstinszenierungspraktiken als Weg zu Stärkenorientierung, Selbstbestimmung und Teilhabe – eine Kollegiale Weiterbildung für multiprofessionelle Akteursgruppen im (inklusiven) Übergang Schule-Beruf VL - 5 ER - TY - CHAP AB - Sind „soziale Medien“ überhaupt ein Thema für die Geschichtswissenschaft? Ja, denn die längere Geschichte der Digitalisierung, in der die „sozialen Medien“ einzuordnen sind, zählt bereits über 80 Jahre. Konrad Zuse und andere Ingenieure entwickelten seit 1941 die ersten Digitalcomputer, Unternehmer*innen, Wissenschaftler*innen und Staatenlenker*innen setzten diese seit den 1950er Jahren für ihre Zwecke ein, die Zivilgesellschaft adaptierte sie in den darauffolgenden Dekaden – all das prägte die sozio-digitale Landschaft der späteren „sozialen Medien“. Als unmittelbar „nach dem Boom“ etwa um 1970 zahlreiche Industriegesellschaften einen strukturellen Wandel in Wirtschaft, Gesellschaft und Politik durchlebten, war eine Antwort darauf die vermehrte Digitalisierung und Vernetzung. Daraus entwickelte sich die 1990er Jahre als markante Dekade von World Wide Web, Google und Chatdiensten. Die Entwicklung der „sozialen Medien“ ist also unter anderem in eine ökonomische und gesellschaftliche Entwicklung der Aufmerksamkeitsökonomie und in die längeren Veränderungen von Wirtschafts- und Gesellschaftsordnungen der Ausdifferenzierung und partiellen Individualisierung seit den 1960er Jahren einzuordnen. Dadurch lässt sich besser verstehen, welche Prämissen ihnen zugrunde lagen, welche Möglichkeitsräume und Probleme sich daraus ergaben und warum sie die heutige Öffentlichkeit in einer bestimmten Art und Weise dominieren – ohne sie jedoch zu determinieren. AU - Schmitt, Martin ID - 52511 KW - Digitalgeschichte KW - Soziale Medien KW - Technikgeschichte KW - World Wide Web KW - Digitalisierung T2 - Soziale Medien – wie sie wurden, was sie sind TI - Die Vorgeschichte der „sozialen Medien“. Über die Träume digitaler Vergemeinschaftung und freier Kommunikation ER - TY - CHAP AB - Twitter ist jetzt X und befindet sich auf dem absteigenden Ast. Auf diesem Ast sitzt Facebook bereits seit längerem. Der Kurzvideodienst Vine, Vorgänger von TikTok, ist Geschichte. Und auch bei Google klingeln die Alarmglocken angesichts der „neuen“ Konkurrenz durch Microsoft und ChatGPT. Umso dringlicher wird also die Historisierung der „sozialen Medien“, das heißt, sie in ihren historischen Kontext einzuordnen und ihren Mythos zu entzaubern. Dabei wartet das Vorhaben mit einer doppelten Herausforderung auf: Erstens, dass es sich bei den Unternehmen der Branche und zweitens auch bei den dort gebildeten Gemeinschaften um recht flüchtige, wandelhaften Gestalten handelt. Scheitern und Wandel ist Teil der „sozialen Medien“ – und sei es nur in der schnellen Abfolge der Moden des „nächsten großen Dings“. Dementsprechend versucht dieser Beitrag mit einem systematischeren Ansatz als dem der gesellschaftlichen Selbstbeschreibung, die Entwicklung des sozio-digitalen Phänomens „soziale Medien“ in dessen Zeitkontext einzuordnen. AU - Schmitt, Martin ID - 52538 KW - Digitalgeschichte KW - Soziale Medien KW - Technikgeschichte KW - Wirtschaftsgeschichte KW - Digitalisierung KW - Twitter KW - Facebook KW - Meta T2 - Soziale Medien – wie sie wurden, was sie sind TI - Alles geht? Die jüngste Geschichte der „sozialen Medien“. Zwischen Wirtschaft und Gemeinschaft ER - TY - JOUR AB - Data-driven models for nonlinear dynamical systems based on approximating the underlying Koopman operator or generator have proven to be successful tools for forecasting, feature learning, state estimation, and control. It has become well known that the Koopman generators for control-affine systems also have affine dependence on the input, leading to convenient finite-dimensional bilinear approximations of the dynamics. Yet there are still two main obstacles that limit the scope of current approaches for approximating the Koopman generators of systems with actuation. First, the performance of existing methods depends heavily on the choice of basis functions over which the Koopman generator is to be approximated; and there is currently no universal way to choose them for systems that are not measure preserving. Secondly, if we do not observe the full state, we may not gain access to a sufficiently rich collection of such functions to describe the dynamics. This is because the commonly used method of forming time-delayed observables fails when there is actuation. To remedy these issues, we write the dynamics of observables governed by the Koopman generator as a bilinear hidden Markov model, and determine the model parameters using the expectation-maximization (EM) algorithm. The E-step involves a standard Kalman filter and smoother, while the M-step resembles control-affine dynamic mode decomposition for the generator. We demonstrate the performance of this method on three examples, including recovery of a finite-dimensional Koopman-invariant subspace for an actuated system with a slow manifold; estimation of Koopman eigenfunctions for the unforced Duffing equation; and model-predictive control of a fluidic pinball system based only on noisy observations of lift and drag. AU - Otto, Samuel E. AU - Peitz, Sebastian AU - Rowley, Clarence W. ID - 33461 IS - 1 JF - SIAM Journal on Applied Dynamical Systems TI - Learning Bilinear Models of Actuated Koopman Generators from Partially-Observed Trajectories VL - 23 ER - TY - JOUR AB - Der Beitrag stellt ein Qualifizierungsformat für (multi)professionelle Bildungsakteur*innen zur entwicklungsförderlichen Nutzung von Selbstinszenierungspraktiken vor. Die Konzeption und Entwicklung des Weiterbildungsformats ist im Rahmen eines Forschungs- und Entwicklungs­projekts für Jugendliche in ausbildungsvorbereitenden Bildungsgängen angesiedelt, die einen besonderen Förderbedarf im Zuge des Übergangs von der Schule in die Berufs- und Arbeitswelt aufweisen. Diese sollen durch offene und kreative Selbstdarstellungs- und Erhebungsformate dabei unterstützt werden, ihre Stärken zu erkennen, zu dokumentieren und sichtbar zu machen, sowie hierüber gleichsam für den Übergang Schule-Beruf gestärkt werden.   Wir stellen zunächst den Projektrahmen vor und schärfen in diesem Kontext den Zugang über eine Grundlegung zu Selbstinszenierung sowie deren Potenziale im Kontext der inklusiven Berufsbildung und zur Stärkung der Zielgruppe. Das im Projekt entwickelte Rahmenkonzept bietet eine Orientierung zur standort- respektive bildungsgangbezogenen Anpassung und stellt damit Herausforderungen und einen entsprechenden Qualifizierungsbedarf für Bildungsakteur­*innen heraus. Darauf basierend stellen wir die konzeptionellen Grundlagen, die methodische und inhaltliche Ausgestaltung zum Ansatz der ‚Kollegialen Weiterbildung‘ zur entwicklungsför­derlichen Nutzung von Selbstinszenierungspraktiken vor und adressieren u. a. das Zusammen­spiel von innovativer Entwicklung, Schärfung von Rollen und Kompetenzentwicklung der Bil­dungsakteur*innen. Abschließend diskutieren wir die konzeptionellen Entwicklungen und den Implementations- und Transferansatz. Abstract The article presents a qualification format for multi-professional actors in the educational context on the developmental use of 'Selbstinszenierungspraktiken' (which means a combination of practices for self-awareness, self-realisation and self-accep­tance in a process which we are developing in our project). The concept and development of the further education format is located within the framework of a research and development project for young people with wide-ranging needs in pre-vocational education units at the transition from school to work. They will be supported in recognizing, documenting and showing their strengths through open and creative self-expression and survey formats, as well as being strengthened for the transition from school to work. First, we present the project framework and clarify the approach by a theoretical grounding of ‚Selbstinszenierung‘ (similar to a combination of self-awareness, self-realisation and self-accep­tance) as well as its potentials in the context of inclusive vocational education by strengthening the target group. The developed framework provides a basis for the adaptation of the concept to a specific location or educational programme and highlights challenges and qualification needs for actors in the educational context. We present the conceptual basis, the methodologi­cal and content-related design of the collegial training approach on the developmental use of 'Selbstinszenierungspraktiken'. We address the interaction of innovative development, cla­rification of roles and competence development of actors in the educational context. Finally, we discuss the conceptual developments and the implementation and transfer approach. AU - Kundisch, Heike AU - Kremer, H.-Hugo AU - Otto, Franziska ID - 52620 IS - 3 JF - QfI - Qualifizierung für Inklusion. Online-Zeitschrift zur Forschung über Aus-, Fort- und Weiterbildung pädagogischer Fachkräfte KW - General Medicine SN - 2699-2477 TI - Selbstinszenierungspraktiken als Weg zu Stärkenorientierung, Selbstbestimmung und Teilhabe – eine Kollegiale Weiterbildung für multiprofessionelle Akteursgruppen im (inklusiven) Übergang Schule-Beruf VL - 5 ER - TY - JOUR AU - Herdramm, Henrike ID - 52652 JF - BloKK. Der Blog des Zentrums für Komparative Theologie und Kulturwissenschaften KW - Ideologiekritik KW - Tiertheologie KW - Tierethik TI - Das Potenzial von Ideologiekritik im Religionsunterricht ER - TY - JOUR AB - We explore the polarization hysteretic behaviour and field-dependent permittivity of ferroelectric-dielectric 2D materials formed by random dispersions of low permittivity inclusions in a ferroelectric matrix, using finite element simulations. We show how the degree of impenetrability of dielectric inclusions plays a substantial role in controlling the coercive field, remnant and saturation polarizations of the homogenized materials. The results highlight the significance of the degree of impenetrability of inclusion in tuning the effective polarization properties of such ferroelectric composites: coercive field drops significantly as percolation threshold is attained and remnant polarization decreases faster than a linear decay. AU - Myroshnychenko, Viktor AU - Mulavarickal Jose, Pious Mathews AU - Farheen, Henna AU - Ejaz, Shafaq AU - Brosseau, Christian AU - Förstner, Jens ID - 52700 IS - 4 JF - Physica Scripta KW - tet_topic_ferro SN - 0031-8949 TI - From Swiss-cheese to discrete ferroelectric composites: assessing the ferroelectric butterfly shape in polarization loops VL - 99 ER - TY - JOUR AB - The editorial introduces the special issue Knowledge by Design in Education: Key challenges and experiences from research practice, posing key questions, offering an insight into ongoing discussions, and presenting an overview of the included articles. AU - Brase, Alexa Kristin AU - Jenert, Tobias ID - 52702 IS - 1 JF - EDeR. Educational Design Research SN - 2511-0667 TI - Knowledge by Design in Education VL - 8 ER - TY - JOUR AB - Heteroclinic structures organize global features of dynamical systems. We analyse whether heteroclinic structures can arise in network dynamics with higher-order interactions which describe the nonlinear interactions between three or more units. We find that while commonly analysed model equations such as network dynamics on undirected hypergraphs may be useful to describe local dynamics such as cluster synchronization, they give rise to obstructions that allow to design of heteroclinic structures in phase space. By contrast, directed hypergraphs break the homogeneity and lead to vector fields that support heteroclinic structures. AU - Bick, Christian AU - von der Gracht, Sören ID - 52726 IS - 2 JF - Journal of Complex Networks KW - Applied Mathematics KW - Computational Mathematics KW - Control and Optimization KW - Management Science and Operations Research KW - Computer Networks and Communications SN - 2051-1329 TI - Heteroclinic dynamics in network dynamical systems with higher-order interactions VL - 12 ER - TY - JOUR AB - Due to the hydrolytic instability of LiPF6 in carbonate-based solvents, HF is a typical impurity in Li-ion battery electrolytes. HF significantly influences the performance of Li-ion batteries, for example by impacting the formation of the solid electrolyte interphase at the anode and by affecting transition metal dissolution at the cathode. Additionally, HF complicates studying fundamental interfacial electrochemistry of Li-ion battery electrolytes, such as direct anion reduction, because it is electrocatalytically relatively unstable, resulting in LiF passivation layers. Methods to selectively remove ppm levels of HF from LiPF6-containing carbonate-based electrolytes are limited. We introduce and benchmark a simple yet efficient electrochemical in situ method to selectively remove ppm amounts of HF from LiPF6-containing carbonate-based electrolytes. The basic idea is the application of a suitable potential to a high surface-area metallic electrode upon which only HF reacts (electrocatalytically) while all other electrolyte components are unaffected under the respective conditions. AU - Ge, Xiaokun AU - Huck, Marten AU - Kuhlmann, Andreas AU - Tiemann, Michael AU - Weinberger, Christian AU - Xu, Xiaodan AU - Zhao, Zhenyu AU - Steinrueck, Hans-Georg ID - 52372 JF - Journal of The Electrochemical Society KW - Materials Chemistry KW - Electrochemistry KW - Surfaces KW - Coatings and Films KW - Condensed Matter Physics KW - Renewable Energy KW - Sustainability and the Environment KW - Electronic KW - Optical and Magnetic Materials SN - 0013-4651 TI - Electrochemical Removal of HF from Carbonate-based LiPF6-containing Li-ion Battery Electrolytes VL - 171 ER - TY - JOUR AU - Boeddeker, Christoph AU - Subramanian, Aswin Shanmugam AU - Wichern, Gordon AU - Haeb-Umbach, Reinhold AU - Le Roux, Jonathan ID - 52958 JF - IEEE/ACM Transactions on Audio, Speech, and Language Processing KW - Electrical and Electronic Engineering KW - Acoustics and Ultrasonics KW - Computer Science (miscellaneous) KW - Computational Mathematics SN - 2329-9290 TI - TS-SEP: Joint Diarization and Separation Conditioned on Estimated Speaker Embeddings VL - 32 ER - TY - GEN AU - Banh, Ngoc Chi AU - Scharlau, Ingrid ID - 53069 TI - Effects of task difficulty on visual processing speed ER - TY - JOUR AB - In this work, we consider optimal control problems for mechanical systems with fixed initial and free final state and a quadratic Lagrange term. Specifically, the dynamics is described by a second order ODE containing an affine control term. Classically, Pontryagin's maximum principle gives necessary optimality conditions for the optimal control problem. For smooth problems, alternatively, a variational approach based on an augmented objective can be followed. Here, we propose a new Lagrangian approach leading to equivalent necessary optimality conditions in the form of Euler-Lagrange equations. Thus, the differential geometric structure (similar to classical Lagrangian dynamics) can be exploited in the framework of optimal control problems. In particular, the formulation enables the symplectic discretisation of the optimal control problem via variational integrators in a straightforward way. AU - Leyendecker, Sigrid AU - Maslovskaya, Sofya AU - Ober-Blöbaum, Sina AU - Almagro, Rodrigo T. Sato Martín de AU - Szemenyei, Flóra Orsolya ID - 53101 JF - Journal of Computational Dynamics KW - Optimal control problem KW - Lagrangian system KW - Hamiltonian system KW - Variations KW - Pontryagin's maximum principle. SN - 2158-2491 TI - A new Lagrangian approach to control affine systems with a quadratic Lagrange term ER - TY - BOOK AB - Tax evasion, tax avoidance and tax resistance are widespread phenomena in political, economic, social and fiscal history from antiquity through medieval, early modern and modern times. Histories of Tax Evasion, Avoidance and Resistance shows how different groups and individuals around the globe have succeeded or failed in not paying their due taxes, whether in kind or in cash, on their properties or on their crops. It analyses how, throughout history, wealthy and poor taxpayers have tried to avoid or reduce their tax burden by negotiating with tax authorities, through practices of legal or illegal tax evasion, by filing lawsuits, seeking armed resistance or by migration, and how state authorities have dealt with such acts of claim making, defiance, open resistance or elusion. It fills an important research gap in tax history, addressing questions of tax morale and fairness, and how social and political inequality was negotiated through taxation. It gives rich insights into the development of citizen-state relationships throughout the course of history. The book comprises case studies from Ancient Athens, Roman Egypt, Medieval Europe, Early Modern Mexico, the Ottoman Empire, Nigeria under British colonial rule, the United Kingdom of the early 20th century, Greece during the Second World War, as well as West Germany, Switzerland, Sweden and the United States in the 20th century, including transnational entanglements in the world of late-modern offshore finance and taxation. The authors are experts in fiscal, economic, financial, legal, social and/or cultural history. The book is intended for students, researchers and scholars of economic and financial history, social and world history and political economy. The Open Access version of this book, available at www.taylorfrancis.com, has been made available under a Creative Commons Attribution-Share Alike 4.0 license. AU - Schönhärl, Korinna AU - Hürlimann, Gisela AU - Rohde, Dorothea ID - 34544 KW - Tax History KW - Financial History SN - 9781003333197 TI - Histories of Tax Evasion, Avoidance and Resistance ER - TY - CHAP AB - Jean Bodin's list on how the absolutist monarchical state could raise its revenue ranked taxation only in seventh place. From a modern legal perspective, taxes are compulsory transfers of resources that households and enterprises pay to one or several government bodies without receiving an individual, specific benefit in return. Historians have dealt with not paying taxes in various contexts, such as analysing tax resistance and tax resistance movements in history. Tax law is best understood as an outcome of long-term, often conflictual, negotiations and as an expression of specific political mentalities and ideologies. As a consequence, tax law and sometimes even the tax juridical system have a strongly politicised character. Loopholes in tax legislation that enable or facilitate avoidance or evasion can thus be regarded as a result of the interest-driven politics of parliamentary majorities, as the success of concerted lobby pressure. AU - Schönhärl, Korinna AU - Hürlimann, Gisela AU - Rohde, Dorothea ED - Schönhärl, Korinna ED - Hürlimann, Gisela ED - Rohde, Dorothea ID - 34546 T2 - Histories of Tax Evasion, Avoidance and Resistance TI - The Ability and Intention of Not Paying Taxes in History. Some Introductory Observations ER - TY - CHAP AB - As a case study, this chapter examines two tax education films that were produced 11 years apart in the USA and Western Germany during and after World War II: “The New Spirit” and “Putzke wants to know”. In contrast to America's most popular cartoon character 11 years earlier, Erwin Putzke is in a terrible mood at the beginning of the short film “Putzke wants to know”. The family father and electrician with a workshop of his own is annoyed and upset by the duty of filling in his tax return, grumbling at his wife and daughter and even at their budgie. The film's tax morale message is conveyed to its audience against the backdrop of a sober post-war reality characterised by allied occupation and the Allies' say in West German tax policies during a period of laborious economic build-up after a lost war. AU - Schönhärl, Korinna ED - Schönhärl, Korinna ED - Hürlimann, Gisela ED - Rohde, Dorothea ID - 34547 T2 - Histories of Tax Evasion, Avoidance and Resistance TI - How to Create a Taxpaying Spirit. A Transnational Examination of an US American and a Western German Tax Education Film in and after World War II ER - TY - JOUR AB - As in almost every other branch of science, the major advances in data science and machine learning have also resulted in significant improvements regarding the modeling and simulation of nonlinear dynamical systems. It is nowadays possible to make accurate medium to long-term predictions of highly complex systems such as the weather, the dynamics within a nuclear fusion reactor, of disease models or the stock market in a very efficient manner. In many cases, predictive methods are advertised to ultimately be useful for control, as the control of high-dimensional nonlinear systems is an engineering grand challenge with huge potential in areas such as clean and efficient energy production, or the development of advanced medical devices. However, the question of how to use a predictive model for control is often left unanswered due to the associated challenges, namely a significantly higher system complexity, the requirement of much larger data sets and an increased and often problem-specific modeling effort. To solve these issues, we present a universal framework (which we call QuaSiModO: Quantization-Simulation-Modeling-Optimization) to transform arbitrary predictive models into control systems and use them for feedback control. The advantages of our approach are a linear increase in data requirements with respect to the control dimension, performance guarantees that rely exclusively on the accuracy of the predictive model, and only little prior knowledge requirements in control theory to solve complex control problems. In particular the latter point is of key importance to enable a large number of researchers and practitioners to exploit the ever increasing capabilities of predictive models for control in a straight-forward and systematic fashion. AU - Peitz, Sebastian AU - Bieker, Katharina ID - 21199 JF - Automatica TI - On the Universal Transformation of Data-Driven Models to Control Systems VL - 149 ER - TY - JOUR AB - Videografien eigenen Unterrichts sind ein mögliches methodisches Werkzeug zur Förderung der professionellen Kompetenz angehender Lehrkräfte, das allerdings innerhalb der Lehramtsausbildung noch nicht breit implementiert ist. Ein möglicher Grund hierfür könnte neben organisatorischen Herausforderungen auch in einer geringen Akzeptanz von Eigenvideografien durch Lehramtsstudierende liegen. Um besser abschätzen zu können, mit welchen Voraussetzungen affektiv-emotionaler Art bei einer breiteren Implementierung im Lehramtsstudium gerechnet werden kann, wurden N = 938 Lehramtsstudierende im Masterstudium an der Universität Paderborn zu ihren Emotionen und Bereitschaften zur Arbeit mit Eigenvideografien befragt. Dabei wurde auch erfasst, wie sich diese je nach bestehenden Erfahrungen zur Arbeit mit Videografien unterscheiden. In den Ergebnissen zeigen sich kaum affektiv-emotionale Reaktionen zur Eigenvideografie, und wenn, vor allem Gefühle der Unsicherheit. Zu beachten ist, dass zwar bei gut der Hälfte der Studierenden eine eher hohe generelle Bereitschaft zur Eigenvideografie besteht, eine konkrete Intention bzw. eine konkrete Volition zur Videografie aber geringer ist. Die ca. 10 % der Studierenden mit Eigenvideografieerfahrung im Studium zeigen erwartungsgemäß höhere Bereitschaften, aber unerwartet keine signifikant positiveren Emotionen. Insgesamt verdeutlichen die Ergebnisse, dass bzgl. der Akzeptanz der Studierenden ein höheres Potenzial zur Implementation von Eigenvideografien im Studium vorliegt, als aktuell ausgeschöpft wird. AU - Vogelsang, Christoph AU - Pollmeier, Pascal AU - Gockeln, Theresa AU - Rogge, Tim ID - 35831 JF - Zeitschrift für Bildungsforschung KW - Lehrerbildung KW - Videografie KW - Praxissemester KW - Emotionen KW - Akzeptanz TI - Zu unangenehm, zu viel Aufwand oder keine Möglichkeit? – Emotionen und Bereitschaft von Lehramtsstudierenden zur Videografie eigenen Unterrichts ER - TY - JOUR AB - Abstract. The miniaturisation of components leads to new demands on measurement systems. One of these is the resolution. As a volumetric analysis method and method of non-destructive testing, industrial X-ray computed tomography (XCT) has the ability to measure geometrical features and their corresponding dimensions without destroying them and can therefore be used for quality assurance. However, the concept of resolution is not trivial for XCT and has not yet been finally clarified. In particular, the interface structural resolution, the detectability of two surfaces facing each other after surface segmentation, faces a lack of a test specimen, a corresponding measurand and a reliable method. Simulation-based XCT investigations of a method to determine this type of resolution are presented in this article using the geometry of a test specimen that contains several radially arranged holes of the same size. The borehole diameters correspond to the distance between the holes to investigate the resolvability of surfaces and interfaces. The evaluation is based on mean and extreme values of grey value profiles between the individual boreholes of the reconstructed volume. It is shown that the geometrical detectability of the test specimen surface and interface can be extended by a reasonable choice of the threshold value for surface segmentation within a defined interval. With regard to the resolving capability, a distinction is made between assured detectability and possible detectability, as well as the threshold value used when using the ISO50 threshold for surface segmentation and measurement chain completion. AU - Busch, Matthias AU - Hausotte, Tino ID - 36800 IS - 1 JF - Journal of Sensors and Sensor Systems KW - Electrical and Electronic Engineering KW - Instrumentation SN - 2194-878X TI - Simulation-based investigation of the metrological interface structural resolution capability of X-ray computed tomography scanners VL - 12 ER - TY - CONF AU - Richter, Cedric AU - Haltermann, Jan Frederik AU - Jakobs, Marie-Christine AU - Pauck, Felix AU - Schott, Stefan AU - Wehrheim, Heike ID - 35426 T2 - 37th IEEE/ACM International Conference on Automated Software Engineering TI - Are Neural Bug Detectors Comparable to Software Developers on Variable Misuse Bugs? ER - TY - CONF AU - Pauck, Felix ID - 35427 T2 - 37th IEEE/ACM International Conference on Automated Software Engineering TI - Scaling Arbitrary Android App Analyses ER - TY - JOUR AB - Chemical phenomena are only observable on a macroscopic level, whereas they are explained by entities on a non-visible level. Students often demonstrate limited ability to link these different levels. Augmented reality (AR) offers the possibility to increase contiguity by embedding virtual models into hands-on experiments. Therefore, this paper presents a pre- and post-test study investigating how learning and cognitive load are influenced by AR during hands-on experiments. Three comparison groups (AR, animation and filmstrip), with a total of N = 104 German secondary school students, conducted and explained two hands-on experiments. Whereas the AR group was allowed to use an AR app showing virtual models of the processes on the submicroscopic level during the experiments, the two other groups were provided with the same dynamic or static models after experimenting. Results indicate no significant learning gain for the AR group in contrast to the two other groups. The perceived intrinsic cognitive load was higher for the AR group in both experiments as well as the extraneous load in the second experiment. It can be concluded that AR could not unleash its theoretically derived potential in the present study. AU - Peeters, Hendrik AU - Habig, Sebastian AU - Fechner, Sabine ID - 37613 IS - 2 JF - Multimodal Technologies and Interaction KW - augmented reality KW - chemistry education KW - models KW - experiment KW - cognitive load SN - 2414-4088 TI - Does Augmented Reality Help to Understand Chemical Phenomena during Hands-On Experiments?–Implications for Cognitive Load and Learning VL - 7 ER - TY - THES AB - Für den Erwerb fachmethodischer Fähigkeiten stellen Laborpraktika eine zentrale Lerngelegenheiten des Physikstudiums dar. Trotz ihrer hohen Bedeutung fehlt ein hochschulfachdidaktischer Diskurs zu einer lehr-lerntheoretischen Fundierung. Zudem wird ihre Lernwirksamkeit aufgrund der bestehenden didaktischen Gestaltung kritisiert. Die weit verbreiteten engmaschigen Aufgabenstellungen enthalten keine Anreize zur tiefergehenden Auseinandersetzung mit den Inhalten. Um der Diskrepanz zwischen den Zielsetzungen und den von den Lernenden erworbenen Fähigkeiten entgegenzuwirken, liegen aktuell nur wenige und zudem nur punktuelle Grundlagen für eine evidenzbasierte Überarbeitung dieses Veranstaltungsformates vor. Ziel dieser Arbeit ist daher, einen Vorschlag für ein performanzorientiertes Kompetenzstrukturmodell auf universitärem Niveau zu entwickeln, das die Inhaltsbereiche, die experimentellen Fähigkeiten und Fertigkeiten sowie die Qualitätsausprägungen experimenteller Handlungen systematisiert.Die Modellierung ist auf Basis der Analyse videografierter experimenteller Performanz von 16 unterschiedlich fähigen Proband:innen realisiert worden. Für die Entwicklung der Dimensionen Fachmethodik und Qualitätsausprägung werden unter Nutzung der qualitativen Forschungsansätze Dokumentarische Methode und Typenbildung die charakteristischen Merkmale universitären Experimentierens identifiziert und anschließend systematisiert. Zur Prüfung der Passung des Modells zur Perspektive der Wissenschaft Physik ist ein Interrating mit einem Fachwissenschaftler durchgeführt worden, das sehr gute Übereinstimmungswerte liefert. Die Passung des Modells zur Perspektive der Praktikumsleiter:innen ist durch ein Expertenrating erfolgt. Ein Rangfolgen-Vergleich zeigt hohe Übereinstimmungswerte. AU - Bauer, Anna Brigitte ID - 37645 TI - Experimentelle Kompetenz Physikstudierender ER - TY - GEN AB - We consider the data-driven approximation of the Koopman operator for stochastic differential equations on reproducing kernel Hilbert spaces (RKHS). Our focus is on the estimation error if the data are collected from long-term ergodic simulations. We derive both an exact expression for the variance of the kernel cross-covariance operator, measured in the Hilbert-Schmidt norm, and probabilistic bounds for the finite-data estimation error. Moreover, we derive a bound on the prediction error of observables in the RKHS using a finite Mercer series expansion. Further, assuming Koopman-invariance of the RKHS, we provide bounds on the full approximation error. Numerical experiments using the Ornstein-Uhlenbeck process illustrate our results. AU - Philipp, Friedrich AU - Schaller, Manuel AU - Worthmann, Karl AU - Peitz, Sebastian AU - Nüske, Feliks ID - 38031 T2 - arXiv:2301.08637 TI - Error bounds for kernel-based approximations of the Koopman operator ER - TY - CONF AB - Jupyter notebooks enable developers to interleave code snippets with rich-text and in-line visualizations. Data scientists use Jupyter notebook as the de-facto standard for creating and sharing machine-learning based solutions, primarily written in Python. Recent studies have demonstrated, however, that a large portion of Jupyter notebooks available on public platforms are undocumented and lacks a narrative structure. This reduces the readability of these notebooks. To address this shortcoming, this paper presents HeaderGen, a novel tool-based approach that automatically annotates code cells with categorical markdown headers based on a taxonomy of machine-learning operations, and classifies and displays function calls according to this taxonomy. For this functionality to be realized, HeaderGen enhances an existing call graph analysis in PyCG. To improve precision, HeaderGen extends PyCG's analysis with support for handling external library code and flow-sensitivity. The former is realized by facilitating the resolution of function return-types. Furthermore, HeaderGen uses type information to perform pattern matching on code syntax to annotate code cells. The evaluation on 15 real-world Jupyter notebooks from Kaggle shows that HeaderGen's underlying call graph analysis yields high accuracy (96.4% precision and 95.9% recall). This is because HeaderGen can resolve return-types of external libraries where existing type inference tools such as pytype (by Google), pyright (by Microsoft), and Jedi fall short. The header generation has a precision of 82.2% and a recall rate of 96.8% with regard to headers created manually by experts. In a user study, HeaderGen helps participants finish comprehension and navigation tasks faster. All participants clearly perceive HeaderGen as useful to their task. AU - Shivarpatna Venkatesh, Ashwin Prasad AU - Wang, Jiawei AU - Li, Li AU - Bodden, Eric ID - 36522 KW - static analysis KW - python KW - code comprehension KW - annotation KW - literate programming KW - jupyter notebook TI - Enhancing Comprehension and Navigation in Jupyter Notebooks with Static Analysis ER - TY - JOUR AU - Pfeiffer, Jella AU - Gutschow, Julia AU - Haas, Christian AU - Möslein, Florian AU - Maspfuhl, Oliver AU - Borgers, Frederik AU - Alpsancar, Suzana ID - 41874 JF - Business & Information Systems Engineering KW - Information Systems SN - 2363-7005 TI - Algorithmic Fairness in AI ER - TY - GEN AU - Süßmann, Johannes ID - 41948 T2 - wissen/leben. Die Zeitung der WWU Münster TI - Zu »wahrer Glückseligkeit« anleiten. WWU-Gründervater Franz von Fürstenberg wollte vor allem den Fortbestand des Landes sichern – ein Gastbeitrag VL - 17/1 ER - TY - JOUR AU - Matthias Philipper ID - 42154 JF - Quick And Easy Journal Title TI - New Quick And Easy Publication - Will be edited by LibreCat team ER - TY - GEN AB - The goal of this paper is to make a strong point for the usage of dynamical models when using reinforcement learning (RL) for feedback control of dynamical systems governed by partial differential equations (PDEs). To breach the gap between the immense promises we see in RL and the applicability in complex engineering systems, the main challenges are the massive requirements in terms of the training data, as well as the lack of performance guarantees. We present a solution for the first issue using a data-driven surrogate model in the form of a convolutional LSTM with actuation. We demonstrate that learning an actuated model in parallel to training the RL agent significantly reduces the total amount of required data sampled from the real system. Furthermore, we show that iteratively updating the model is of major importance to avoid biases in the RL training. Detailed ablation studies reveal the most important ingredients of the modeling process. We use the chaotic Kuramoto-Sivashinsky equation do demonstarte our findings. AU - Werner, Stefan AU - Peitz, Sebastian ID - 42160 T2 - arXiv:2302.07160 TI - Learning a model is paramount for sample efficiency in reinforcement learning control of PDEs ER - TY - JOUR AB - Regularization is used in many different areas of optimization when solutions are sought which not only minimize a given function, but also possess a certain degree of regularity. Popular applications are image denoising, sparse regression and machine learning. Since the choice of the regularization parameter is crucial but often difficult, path-following methods are used to approximate the entire regularization path, i.e., the set of all possible solutions for all regularization parameters. Due to their nature, the development of these methods requires structural results about the regularization path. The goal of this article is to derive these results for the case of a smooth objective function which is penalized by a piecewise differentiable regularization term. We do this by treating regularization as a multiobjective optimization problem. Our results suggest that even in this general case, the regularization path is piecewise smooth. Moreover, our theory allows for a classification of the nonsmooth features that occur in between smooth parts. This is demonstrated in two applications, namely support-vector machines and exact penalty methods. AU - Gebken, Bennet AU - Bieker, Katharina AU - Peitz, Sebastian ID - 27426 IS - 3 JF - Journal of Global Optimization TI - On the structure of regularization paths for piecewise differentiable regularization terms VL - 85 ER - TY - JOUR AU - Alhaddad, Samer AU - Förstner, Jens AU - Grynko, Yevgen ID - 43018 JF - Journal of Quantitative Spectroscopy and Radiative Transfer KW - tet_topic_scattering SN - 0022-4073 TI - Numerical study of light backscattering from layers of absorbing irregular particles larger than the wavelength VL - 302 ER - TY - CONF AU - Hoffmann, Max AU - Biehler, Rolf ED - Trigueros, Marı́a ED - Barquero, Berta ED - Hochmuth, Reinhard ED - Peters, Jana ID - 31849 KW - Teaching and learning of specific topics in university mathematics KW - Transition to KW - across and from university mathematics KW - Student Teachers KW - Geometry KW - Congruence KW - Double Discontinuity. T2 - Proceedings of the Fourth Conference of the International Network for Didactic Research in University Mathematics (INDRUM 2022, 19-22 October 2022) TI - Student Teachers ’ Knowledge of Congruence before a University Course on Geometry ER - TY - CONF AU - Florensa, Ignasio AU - Hoffmann, Max AU - Romo Vázquez, Avenilde AU - Zandieh, Michelle AU - Martínez-Planell, Rafael ED - Trigueros, Marı́a ED - Barquero, Berta ED - Hochmuth, Reinhard ED - Peters, Jana ID - 43097 T2 - Proceedings of the Fourth Conference of the International Network for Didactic Research in University Mathematics (INDRUM 2022, 19-22 October 2022) TI - Innovations in university teaching based on mathematic education research ER - TY - GEN AU - Süßmann, Johannes ID - 43186 TI - Pantheon ER - TY - JOUR AB - Lightweight design is a common approach to reduce energy demand in the use stage of vehicles. The production of lightweight materials is usually associated with an increase in energy demand, so the environmental impacts of lightweight structures need to be assessed holistically using a life cycle assessment. To estimate the life cycle environmental impacts of a product in its developmental stage, for example, by life cycle engineering, future changes in relevant influencing factors must be considered. Prospective life cycle assessment provides methods for integrating future scenarios into life cycle assessment studies. However, approaches for integrating prospective life cycle assessment into product development are limited. The objective of this work is to provide the methodological foundation for integrating future scenarios of relevant influencing factors in the development of lightweight structures. The applicability of the novel methodology is demonstrated by a case study of a structural component in a steel, aluminium, and hybrid design. The results show that appropriate decarbonisation measures can reduce the life cycle greenhouse gas emissions by up to 95 percent until 2050. We also found that shifts in the environmentally optimal design are possible in future scenarios. Therefore, the methodology and data provided contribute to improved decision-making in product development. AU - Ostermann, Moritz AU - Grenz, Julian AU - Triebus, Marcel AU - Cerdas, Felipe AU - Marten, Thorsten AU - Tröster, Thomas AU - Herrmann, Christoph ID - 43464 IS - 8 JF - Energies KW - Life Cycle Engineering KW - Life Cycle Assessment KW - Lightweight Design KW - Prospective LCA KW - Future-oriented LCA KW - Energy System KW - Material production KW - Sustainable production SN - 1996-1073 TI - Integrating Prospective Scenarios in Life Cycle Engineering: Case Study of Lightweight Structures VL - 16 ER - TY - JOUR AB - A relatively small body of research has been conducted on the near- and long-term effects of study abroad (SA) to date. This existing research suggests that SA effects on language skills tend to be volatile, while the impact on various aspects of learners’ personal, academic, and professional development may be longer-lasting. Yet, learner perspectives on the dynamics and durability of such effects, in particular in the context of short-term SA programs, remain largely unexplored. This study hence investigates the near-term impact of short-term SA programs as experienced by students within the first months and years following their sojourns. A qualitative case-study design is employed to examine the accounts of four American students of German, who studied abroad in Austria for four weeks and were interviewed repeatedly over a period of up to 40 months after their sojourns. The results suggest that, from the students’ perspective, many effects deteriorate in the near term, although the overall sojourn experience still appears influential. Abstract in German Nur wenige Forschungsvorhaben haben sich bislang den mittel- bis langfristigen Auswirkungen studentischer Auslandsaufenthalte gewidmet; die bisherige Datenlage deutet jedoch darauf hin, dass die Auswirkungen auf sprachliche Kompetenzen eher unbeständig sind, wohingegen die persönliche, studiums- und berufsbezogene Entwicklung der Lernenden länger von einem Auslandsaufenthalt beeinflusst wird. Die Dynamik und Beständigkeit derartiger Auswirkungen wurden jedoch kaum mit Blick auf kurze Auslandsaufenthalte (≤ acht Wochen) sowie aus der Perspektive der Studierenden erforscht, was die vorliegende Studie insbesondere hinsichtlich mittelfristiger Effekte fokussiert. Mittels eines qualitativen Fallstudiendesigns werden die Interviewdaten vier amerikanischer Deutschlernender untersucht, die sich vier Wochen in Österreich aufhielten und in einem Zeitraum von bis zu 40 Monaten nach ihrem Aufenthalt wiederholt befragt wurden. Die Ergebnisse zeigen, dass viele Auswirkungen eines solchen Aufenthalts aus studentischer Perspektive mittelfristig verblassen, auch wenn der Auslandsaufenthalt im Gesamten weiterhin als einflussreiche Erfahrung wahrgenommen wird. AU - Müller, Mareike ID - 44058 IS - 1 JF - Frontiers: The Interdisciplinary Journal of Study Abroad SN - 2380-8144 TI - Near-Term Effects of Short-Term Study Abroad: A Longitudinal Examination of Learner Perceptions VL - 35 ER - TY - JOUR AB - Die Wirtschaftlichkeit von Wärmemotoren wird maßgeblich durch die Rückführung von Wärme in Rekuperatoren beeinflusst. Beim isobaren Expansionsmotor vom Bush-Typ, einem Wärmemotor, welcher bereits mit Wärmequellen ab 60°C betrieben werden kann, steigt der thermische Wirkungsgrad durch den Einsatz von Rekuperatoren signifikant. Gleichzeitig wirken sich das Fluidvolumen des Wärmeübertragers sowie der beim Betrieb auftretende Druckverlust negativ auf den thermischen Wirkungsrad aus. In dieser Arbeit wird der Zusammenhang von Totvolumen, Druckverlust und Wärmerückgewinnung untersucht und Empfehlungen für den Betrieb von Rekuperatoren am isobaren Expansionsmotor gegeben. AU - Mügge, Nils AU - Kronberg, Alexander AU - Glushenkov, Maxim AU - Kenig, Eugeny Y. ID - 42252 IS - 5 JF - Chemie Ingenieur Technik KW - Isobarer Expansionsmotor KW - Dynamische Wärmeübertragungsmodellierung KW - Phasenwechsel KW - dichte Arbeitsmedien TI - Untersuchung überlagerter Effekte von Druckverlust und Totvolumen durch Rekuperation am isobaren Expansionsmotor VL - 95 ER - TY - JOUR AB - AbstractThe use of structured measuring systems to prevent wall slip is a common approach to obtain absolute rheological values. Typically, only the minimum distance between the measuring surfaces is used for further calculation, implying that no flow occurs between the structural elements. But this assumption is misleading, and a gap correction is necessary. To determine the radius correction $$\Delta r$$ Δ r for specific geometries, we conducted investigations on three Newtonian fluids (two silicon oils and one suspension considered to be Newtonian in the relevant shear rate range). The results show that $$\Delta r$$ Δ r is not only shear- and material-independent, but geometry-dependent, providing a Newtonian flow behaviour in a similar viscosity range. Therefore, a correction value can be determined with only minute deviations in different Newtonian fluids. As the conducted laboratory measurements are very time-consuming and expensive, a CFD-approach with only very small deviations was additionally developed and compared for validation purposes. Therefore, simulation is an effective and resource-efficient alternative to the presented laboratory measurements to determine $$\Delta r$$ Δ r for the correction of structured coaxial geometries even for non-Newtonian fluids in the future. AU - Josch, Sebastian AU - Jesinghausen, Steffen AU - Dechert, Christopher AU - Schmid, Hans-Joachim ID - 36983 JF - Rheologica Acta KW - rheology KW - rheometry KW - suspension KW - coaxial KW - correction SN - 0035-4511 TI - Experimental and simulative determination and correction of the effective gap extension in structured coaxial measuring systems ER - TY - CONF AB - We present an approach for guaranteed constraint satisfaction by means of data-based optimal control, where the model is unknown and has to be obtained from measurement data. To this end, we utilize the Koopman framework and an eDMD-based bilinear surrogate modeling approach for control systems to show an error bound on predicted observables, i.e., functions of the state. This result is then applied to the constraints of the optimal control problem to show that satisfaction of tightened constraints in the purely data-based surrogate model implies constraint satisfaction for the original system. AU - Schaller, Manuel AU - Worthmann, Karl AU - Philipp, Friedrich AU - Peitz, Sebastian AU - Nüske, Feliks ID - 30125 IS - 1 T2 - IFAC-PapersOnLine TI - Towards reliable data-based optimal and predictive control using extended DMD VL - 56 ER - TY - JOUR AB - AU - Heck, Tamara AU - Steinhardt, Isabel AU - Rahal, Rima-Maria AU - Schubotz, Moritz AU - Scholl, Dominik AU - Behrens, Sarah ID - 43094 JF - Research Ideas and Outcomes KW - Open Science SN - 2367-7163 TI - Bootstrapping the Open Science culture: The fellowship approach VL - 9 ER - TY - GEN ED - Meine, Sabine ED - Otto, Arnold ED - Süßmann, Johannes ID - 35062 SN - 978-3-8260-7218-5 TI - Musiklandschaften zwischen Rhein und Weser. Pluralisierung und Verflechtung entlang des Hellwegs in der Frühen Neuzeit. Unter Mitarbeit v. Markus Lauert VL - 13 ER - TY - JOUR AB - High-contrast slab waveguide Bragg gratings with 1D periodicity are investigated. For specific oblique excitation by semi-guided waves at sufficiently high angles of incidence, the idealized structures do not exhibit any radiative losses, such that reflectance and transmittance for the single port mode add strictly up to one. We consider a series of symmetric, fully and partly etched finite gratings, for parameters found in integrated silicon photonics. These can act as spectral filters with a reasonably flattop response. Apodization can lead to more box shaped reflectance and transmittance spectra. Together with a narrowband Fabry–Perot filter, these configurations are characterized by reflection bands, or transmittance peaks, with widths that span three orders of magnitude. AU - Hammer, Manfred AU - Farheen, Henna AU - Förstner, Jens ID - 43245 IS - 4 JF - Journal of the Optical Society of America B KW - tet_topic_waveguide SN - 0740-3224 TI - How to suppress radiative losses in high-contrast integrated Bragg gratings VL - 40 ER - TY - GEN AU - Meier, Torsten AU - Grisard, S. AU - Trifonov, A.V. AU - Rose, Hendrik AU - Reichhardt, R. AU - Reichelt, Matthias AU - Schneider, C. AU - Kamp, M. AU - Höfling, S. AU - Bayer, M. AU - Akimov, I.A ID - 43132 T2 - arxiv:2302.02480 TI - Temporal sorting of optical multi-wave-mixing processes in semiconductor quantum dots ER - TY - JOUR AB - We present strong enhancement of third harmonic generation in an amorphous silicon metasurface consisting of elliptical nano resonators. We show that this enhancement originates from a new type of multi-mode Fano mechanism. These ‘Super-Fano’ resonances are investigated numerically in great detail using full-wave simulations. The theoretically predicted behavior of the metasurface is experimentally verified by linear and nonlinear transmission spectroscopy. Moreover, quantitative nonlinear measurements are performed, in which an absolute conversion efficiency as high as ηmax ≈ 2.8 × 10−7 a peak power intensity of 1.2 GW cm−2 is found. Compared to an unpatterned silicon film of the same thickness amplification factors of up to ~900 are demonstrated. Our results pave the way to exploiting a strong Fano-type multi-mode coupling in metasurfaces for high THG in potential applications. AU - Hähnel, David AU - Golla, Christian AU - Albert, Maximilian AU - Zentgraf, Thomas AU - Myroshnychenko, Viktor AU - Förstner, Jens AU - Meier, Cedrik ID - 44097 IS - 1 JF - Light: Science & Applications KW - tet_topic_meta SN - 2047-7538 TI - A multi-mode super-fano mechanism for enhanced third harmonic generation in silicon metasurfaces VL - 12 ER - TY - BOOK AU - Bauer, Anna Brigitte ID - 44083 SN - 978-3-8325-5625-9 TI - Experimentelle Kompetenz Physikstudierender. Entwicklung und erste Erprobung eines performanzorientierten Kompetenzstrukturmodells unter Nutzung qualitativer Methoden VL - 352 ER - TY - GEN AU - Schürmann, Patrick ID - 43374 TI - A Formal Comparison of Advanced Digital Signature Primitives ER - TY - JOUR AB - Microcellular wood fiber reinforced polymers offer the possibility to reduce the use of fossil raw materials. In particular, thick-walled structures with thicknesses greater than 6 mm offer a high potential for weight savings. This study investigates the cell structures and mechanical properties of injection-molded test specimens. The influence of different thicknesses (6–10 mm) along with different chemical blowing agents (endothermic, exothermic) with varying dosages (0–2 wt%) is analyzed. The investigations reveal that exothermic chemical blowing agents form finer cells consistently to thin-walled structures than endothermic ones. Higher foaming agent content leads to higher pore fractions, with many small cells coalescing into a large open-pore cell network. The mechanical properties depend mainly on the pore content of the sample. The specific tensile properties deteriorate with the use of chemical blowing agents (CFA), whereas the sandwich structure produced with compact edge layers has a positive influence on the specific flexural properties. AU - Moritzer, Elmar AU - Flachmann, Felix ID - 42515 IS - 3 JF - Journal of Cellular Plastics KW - Materials Chemistry KW - Polymers and Plastics KW - General Chemistry SN - 0021-955X TI - Morphological and mechanical properties of foamed thick-walled Wood-Plastic-Composite structures VL - 59 ER - TY - JOUR AU - Burmeister, Sascha Christian AU - Schryen, Guido ID - 42179 JF - Energy Systems TI - Distribution Network Optimization: Predicting computation times to design scenario analysis for network operators ER - TY - JOUR AB - Abstract The accessibility to rheological parameters for concrete is becoming more and more relevant. This is mainly related to the constantly emerging challenges, such as not only the development of high-strength concretes is progressing very fast but also the simulation of the flow behaviour is of high importance. The main problem, however, is that the rheological characterisation of fresh concrete is not possible via commercial rheometers. The so-called concrete rheometers provide valuable relative values for comparing different concretes, but they cannot measure absolute values. Therefore, we developed an adaptive coaxial concrete rheometer (ACCR) that allows the measurement of fresh concrete with particles up to d max = 5.5 mm {d}_{{\rm{\max }}}=5.5\hspace{.5em}{\rm{mm}} . The comparison of the ACCR with a commercial rheometer showed very good agreement for selected test materials (Newtonian fluid, shear thinning fluid, suspension, and yield stress fluid), so that self-compacting concrete was subsequently measured. Since these measurements showed a very high reproducibility, the rheological properties of the fresh concrete could be determined with high accuracy. The common flow models (Bingham (B), Herschel–Bulkley, modified Bingham (MB) models) were also tested for their applicability, with the Bingham and the modified Bingham model proving to be the best suitable ones. AU - Josch, Sebastian AU - Jesinghausen, Steffen AU - Schmid, Hans-Joachim ID - 43034 IS - 1 JF - Applied Rheology KW - Condensed Matter Physics KW - General Materials Science SN - 1617-8106 TI - Development of an adaptive coaxial concrete rheometer and rheological characterisation of fresh concrete VL - 33 ER - TY - CHAP AB - State education in honest tax payment can be understood as a facet of training in citizenship, i.e. as an attempt by the modern state to standardize the behavior of its citizens and to prevent deviations. Based on this Foucauldian understanding, this exploratory article examines tax education in the United States, Spain, and West Germany from the mid-1940s to the late 1980s. During this period, the USA asserted itself as the champion of tax education and Spain consistently tried to emulate this example, albeit with more modest means and different semantic strategies from as early as the 1960s, when it was still under a autoritarian regime. The FRG, however, completely discontinued its few early attempts at tax education from the mid-1950s onwards. Even during the economic crises and tax scandals of the 1970s, there was no relaunch of the programs. The article locates the reasons for this highly uneven development in the different ideal images of the citizen in the three states. AU - Schönhärl, Korinna AU - Düll, Nasrin AU - Ramírez Lugo , Nadya Melina ED - Sébastien, Guex ED - Hadrien, Buclin ID - 44249 T2 - Tax Evasion and Tax Havens since the Nineteenth Century TI - Tax Education After WWII: How Spain, the USA, and West Germany Tried to Make Their Citizens Pay Honestly ER - TY - JOUR AU - Neumann, Phillip ID - 44321 IS - 5 JF - Zeitschrift für Heilpädagogik KW - Inklusion KW - Sonderpädagogik KW - Bildung KW - Bildungsstudien KW - Integration SN - 0513-9066 TI - Studien zu Schulleistungen und ihre Aufbereitung VL - 74 ER - TY - CHAP AU - Meine, Sabine AU - Otto, Arnold AU - Süßmann, Johannes ID - 35063 SN - 978-3-8260-7218-5 T2 - Musiklandschaften zwischen Rhein und Weser. Pluralisierung und Verflechtung entlang des Hellwegs in der Frühen Neuzeit. Unter Mitarbeit v. Markus Lauert TI - Musiklandschaften zwischen Rhein und Weser – Einführung ER - TY - CONF AU - Gharibian, Sevag AU - Watson, James AU - Bausch, Johannes ID - 20841 T2 - Proceedings of the 40th International Symposium on Theoretical Aspects of Computer Science (STACS) TI - The Complexity of Translationally Invariant Problems beyond Ground State Energies VL - 254 ER - TY - GEN AB - For open world applications, deep neural networks (DNNs) need to be aware of previously unseen data and adaptable to evolving environments. Furthermore, it is desirable to detect and learn novel classes which are not included in the DNNs underlying set of semantic classes in an unsupervised fashion. The method proposed in this article builds upon anomaly detection to retrieve out-of-distribution (OoD) data as candidates for new classes. We thereafter extend the DNN by $k$ empty classes and fine-tune it on the OoD data samples. To this end, we introduce two loss functions, which 1) entice the DNN to assign OoD samples to the empty classes and 2) to minimize the inner-class feature distances between them. Thus, instead of ground truth which contains labels for the different novel classes, the DNN obtains a single OoD label together with a distance matrix, which is computed in advance. We perform several experiments for image classification and semantic segmentation, which demonstrate that a DNN can extend its own semantic space by multiple classes without having access to ground truth. AU - Uhlemeyer, Svenja AU - Lienen, Julian AU - Hüllermeier, Eyke AU - Gottschalk, Hanno ID - 44512 T2 - arXiv:2305.00983 TI - Detecting Novelties with Empty Classes ER - TY - JOUR AB - With enhancing digitalization, condition monitoring is used in an increasing number of application fields across various industrial sectors. By its application, increased reliability as well as reduced risks and costs can be achieved. Based on different approaches, technical systems are monitored and measured data is analyzed to enable condition-based or predictive maintenance. To this end, machine learning approaches are usually implemented to diagnose the health states or predict the health index of the monitored system. However, these trained models are often black-box models, not intuitively explainable for a human. To overcome this shortcoming, a model-based approach based on physics is developed for piezoelectric bending actuators. Such a model enables a transparent representation of the system. Moreover, the model-based approach is extended by a parameter-estimation to account for sudden changes in behavior e. g. caused by occurring cracks. AU - Bender, Amelie ID - 44672 JF - Sensors and Actuators A: Physical KW - Condition Monitoring KW - Model-based approach Diagnostics KW - Varying conditions KW - Explainability KW - Piezoelectric bending actuators SN - 0924-4247 TI - Model-based condition monitoring of piezoelectric bending actuators VL - 357 ER - TY - CONF AU - Ahmed, Qazi Arbab AU - Awais, Muhammad AU - Platzner, Marco ID - 44194 T2 - The 24th International Symposium on Quality Electronic Design (ISQED'23), San Francisco, Califorina USA TI - MAAS: Hiding Trojans in Approximate Circuits ER - TY - JOUR AB - Dispersion is present in every optical setup and is often an undesired effect, especially in nonlinear-optical experiments where ultrashort laser pulses are needed. Typically, bulky pulse compressors consisting of gratings or prisms are used to address this issue by precompensating the dispersion of the optical components. However, these devices are only able to compensate for a part of the dispersion (second-order dispersion). Here, we present a compact pulse-shaping device that uses plasmonic metasurfaces to apply an arbitrarily designed spectral phase delay allowing for a full dispersion control. Furthermore, with specific phase encodings, this device can be used to temporally reshape the incident laser pulses into more complex pulse forms such as a double pulse. We verify the performance of our device by using an SHG-FROG measurement setup together with a retrieval algorithm to extract the dispersion that our device applies to an incident laser pulse. AU - Geromel, René AU - Georgi, Philip AU - Protte, Maximilian AU - Lei, Shiwei AU - Bartley, Tim AU - Huang, Lingling AU - Zentgraf, Thomas ID - 44044 IS - 8 JF - Nano Letters KW - Mechanical Engineering KW - Condensed Matter Physics KW - General Materials Science KW - General Chemistry KW - Bioengineering SN - 1530-6984 TI - Compact Metasurface-Based Optical Pulse-Shaping Device VL - 23 ER - TY - JOUR AB - Hydrothermal carbonization (HTC) is an efficient thermochemical method for the conversion of organic feedstock to carbonaceous solids. HTC of different saccharides is known to produce microspheres (MS) with mostly Gaussian size distribution, which are utilized as functional materials in various applications, both as pristine MS and as a precursor for hard carbon MS. Although the average size of the MS can be influenced by adjusting the process parameters, there is no reliable mechanism to affect their size distribution. Our results demonstrate that HTC of trehalose, in contrast to other saccharides, results in a distinctly bimodal sphere diameter distribution consisting of small spheres with diameters of (2.1 ± 0.2) μm and of large spheres with diameters of (10.4 ± 2.6) μm. Remarkably, after pyrolytic post-carbonization at 1000 °C the MS develop a multimodal pore size distribution with abundant macropores > 100 nm, mesopores > 10 nm and micropores < 2 nm, which were examined by small-angle X-ray scattering and visualized by charge-compensated helium ion microscopy. The bimodal size distribution and hierarchical porosity provide an extraordinary set of properties and potential variables for the tailored synthesis of hierarchical porous carbons, making trehalose-derived hard carbon MS a highly promising material for applications in catalysis, filtration, and energy storage devices. AU - Wortmann, Martin AU - Keil, Waldemar AU - Diestelhorst, Elise AU - Westphal, Michael AU - Haverkamp, René AU - Brockhagen, Bennet AU - Biedinger, Jan AU - Bondzio, Laila AU - Weinberger, Christian AU - Baier, Dominik AU - Tiemann, Michael AU - Hütten, Andreas AU - Hellweg, Thomas AU - Reiss, Günter AU - Schmidt, Claudia AU - Sattler, Klaus AU - Frese, Natalie ID - 44837 IS - 21 JF - RSC Advances KW - General Chemical Engineering KW - General Chemistry SN - 2046-2069 TI - Hard carbon microspheres with bimodal size distribution and hierarchical porosity via hydrothermal carbonization of trehalose VL - 13 ER - TY - CONF AU - Dreiling, Dmitrij AU - Itner, Dominik AU - Hetkämper, Tim AU - Birk, Carolin AU - Gravenkamp, Hauke AU - Henning, Bernd ID - 45205 SN - 978-3-9819376-8-8 T2 - SMSI 2023 Conference TI - Improved determination of viscoelastic material parameters using a pulse-echo measurement setup ER - TY - GEN AU - Koch, Angelina ID - 43375 TI - Privacy-Preserving Collection and Evaluation of Log Files ER - TY - JOUR AU - Schryen, Guido AU - Sperling, Martina ID - 44361 IS - September JF - Computers & Operations Research TI - Literature Reviews in Operations Research: A New Taxonomy and a Meta Review VL - 157 ER - TY - JOUR AB - Dielectric metasurfaces provide a unique platform for efficient harmonic generation and optical wavefront manipulation at the nanoscale. Tailoring phase and amplitude of a nonlinearly generated wave with a high emission efficiency using resonance-based metasurfaces is a challenging task that often requires state-of-the-art numerical methods. Here, we propose a simple yet effective approach combining a sampling method with a Monte Carlo approach to design the third-harmonic wavefront generated by all-dielectric metasurfaces composed of elliptical silicon nanodisks. Using this approach, we theoretically demonstrate the full nonlinear 2π phase control with a uniform and highest possible amplitude in the considered parameter space, allowing us to design metasurfaces operating as third harmonic beam deflectors capable of steering light into a desired direction with high emission efficiency. The TH beam deflection with a record calculated average conversion efficiency of 1.2 × 10–1 W–2 is achieved. We anticipate that the proposed approach will be widely applied as alternative to commonly used optimization algorithms with higher complexity and implementation effort for the design of metasurfaces with other holographic functionalities. AU - Hähnel, David AU - Förstner, Jens AU - Myroshnychenko, Viktor ID - 45596 JF - ACS Photonics KW - tet_topic_meta SN - 2330-4022 TI - Efficient Modeling and Tailoring of Nonlinear Wavefronts in Dielectric Metasurfaces ER - TY - CHAP AU - Freymuth, Nina ED - Balz, HHans-Jürgen ED - Huneke, Annika ED - Kuhlmann, Carola ED - Römisch, Kathrin ID - 45606 T2 - Diskriminierungsprozesse und Teilhabeperspektiven - Herausforderungen für die Praxis der Inklusion. Ausgewählte Master-Thesen 2018-2022 des Masterstudiengangs "Soziale Inklusion: Gesundheit und Bildung" der Evangelischen Hochschule Rheinland-Westfalen-Lippe TI - Alternative für alle? Inklusionsspezifische Analyse der AfD und ihrer Wähler*innen ER - TY - JOUR AU - Dieter, Peter AU - Caron, Matthew AU - Schryen, Guido ID - 44383 IS - 1 JF - European Journal of Operational Research (EJOR) TI - Integrating driver behavior into last-mile delivery routing: Combining machine learning and optimization in a hybrid decision support framework VL - 311 ER - TY - JOUR AU - Meier, Jana AU - Janzen, Thomas AU - Wotschel, Philipp AU - Vogelsang, Christoph ID - 45672 JF - die hochschullehre TI - Rollenspielbasierte Simulationen als Übungs- und Prüfungsformate im Lehramtsstudium. Eine explorative Studie zu Erfahrungen und Einschätzungen aus Studierendensicht. VL - 9 ER - TY - CONF AU - Hotegni, Sedjro Salomon AU - Mahabadi, Sepideh AU - Vakilian, Ali ID - 45695 KW - Fair range clustering T2 - Proceedings of the 40th International Conference on Machine Learning, Honolulu, Hawaii, USA. PMLR 202, 2023. TI - Approximation Algorithms for Fair Range Clustering ER - TY - CONF AU - Hebrok, Sven Niclas AU - Nachtigall, Simon AU - Maehren, Marcel AU - Erinola, Nurullah AU - Merget, Robert AU - Somorovsky, Juraj AU - Schwenk, Jörg ID - 43060 T2 - 32nd USENIX Security Symposium TI - We Really Need to Talk About Session Tickets: A Large-Scale Analysis of Cryptographic Dangers with TLS Session Tickets ER - TY - JOUR AB - Faradaic reactions including charge transfer are often accompanied with diffusion limitation inside the bulk. Conductive two-dimensional frameworks (2D MOFs) with a fast ion transport can combine both - charge transfer and fast diffusion inside their porous structure. To study remaining diffusion limitations caused by particle morphology, different synthesis routes of Cu-2,3,6,7,10,11-hexahydroxytriphenylene (Cu3(HHTP)2), a copper-based 2D MOF, are used to obtain flake- and rod-like MOF particles. Both morphologies are systematically characterized and evaluated for redox-active Li+ ion storage. The redox mechanism is investigated by means of X-ray absorption spectroscopy, FTIR spectroscopy and in situ XRD. Both types are compared regarding kinetic properties for Li+ ion storage via cyclic voltammetry and impedance spectroscopy. A significant influence of particle morphology for 2D MOFs on kinetic aspects of electrochemical Li+ ion storage can be observed. This study opens the path for optimization of redox active porous structures to overcome diffusion limitations of Faradaic processes. AU - Wrogemann, Jens Matthies AU - Lüther, Marco Joes AU - Bärmann, Peer AU - Lounasvuori, Mailis AU - Javed, Ali AU - Tiemann, Michael AU - Golnak, Ronny AU - Xiao, Jie AU - Petit, Tristan AU - Placke, Tobias AU - Winter, Martin ID - 44116 IS - 26 JF - Angewandte Chemie International Edition KW - General Chemistry KW - Catalysis SN - 1433-7851 TI - Overcoming Diffusion Limitation of Faradaic Processes: Property‐Performance Relationships of 2D Conductive Metal‐Organic Framework Cu3(HHTP)2 for Reversible Lithium‐Ion Storage VL - 62 ER - TY - GEN ED - Eckel, Julia ED - Ernst, Christoph ED - Schröter, Jens ID - 36842 IS - 1 KW - tech demo KW - technology demonstration KW - demo or die SN - 1619-1641 T2 - Navigationen - Zeitschrift für Medien- und Kulturwissenschaften TI - Navigationen: Tech | Demo VL - 23 ER -