TY - CHAP AU - Herzig, Bardo AU - Martin, Alexander AU - Klar, Tilman-Mathies ED - Knopf, Julia ED - Abraham, Ulf ID - 20123 SN - 978-3-8340-2048-2 T2 - Deutsch Digital. Band 1 Theorie (2. Aufl.) TI - Mobile Medien – Medienpädagogische und technische Grundlagen, Potential für den Deutschunterricht und Beispiele. ER - TY - GEN AU - Kundisch, Dennis AU - Beverungen, Daniel ID - 20131 TI - Als Wirtschaftsinformatiker die digitale Transformation in Organisationen gestalten ER - TY - CONF AU - Spliethöver, Maximilian AU - Wachsmuth, Henning ID - 20139 T2 - Proceedings of the 7th Workshop on Argument Mining (ArgMining 2020) TI - Argument from Old Man's View: Assessing Social Bias in Argumentation ER - TY - CONF AU - Dorsch, Jonas AU - Wachsmuth, Henning ID - 20140 T2 - Proceedings of the 7th Workshop on Argument Mining (ArgMining 2020) TI - Semi-Supervised Cleansing of Web Argument Corpora ER - TY - GEN AB - Der Karosseriebau ist zunehmend durch die Verwendung unterschiedlicher Werkstoffe in Mischbauweise gekennzeichnet, was zu einem Einsatz von mechanischen Fügeverfahren geführt hat. Hieraus resultieren die Zielsetzungen, die mechanischen Fügeverfahren in ihrer Effizienz und ihren Einsatzbereichen zu erweitern, sowie die Anzahl der Experimente zu reduzieren und Entwicklungszyklen zu verkürzen. Dies erfolgt mit Unterstützung der numerischen Simulation. Neben der Beschreibung des plastischen Verhaltens gilt es auch, das Schädigungsverhalten abzubilden. Der Fügeprozess bzw. die Fügerichtung erfolgt senkrecht zur Blechoberfläche und führt somit zu einem dreidimensionalen Zustand der Fügelemente. Hieraus leitet sich die Herausforderung ab, das Werkstoffversagen in Abhängigkeit der Beanspruchungssituation zu beschreiben. Ein einfacher Ansatz zur Abbildung des Durchdringens ist ein geometrisches Trennkriterium. Ein solches Kriterium basiert i.d.R. auf einem experimentell beobachteten Verhalten und ist somit nicht prognosefähig für Variationen bzgl. Werkzeugkonfigurationen, Blechdicken- und Werkstoffgüten-Kombinationen. In diesem Projekt wird das Schädigungsmodell GISSMO (Generalized Incremental Stress State dependent damage Model) verwendet, um die Entwicklung der duktilen Schädigung zu beschreiben und den Bruchbeginn während des Stanzniet- und Schneidclinchens vorherzusagen. Der Spannungszustand während der Prozesssimulation wird untersucht und die verschiedenen Schädigungsproben werden experimentell erprobt, um die Versagenskurven zu charakterisieren. Die Versagenskurven werden im Schädigungsmodell GISSMO definiert. Um die Genauigkeit des Modells zu gewährleisten, wird die Verifizierung des Modells durch die Simulation von Schädigungsproben mit dem Schädigungsmodell durchgeführt. Zur Validierung des Modells wird die Simulation des Fügeprozesses mit dem Schädigungsmodell durchgeführt und die Ergebnisse von Simulation und Experiment verglichen. Darüber hinaus werden Sensitivitätsanalysen durchgeführt, um die Einflüsse der Fertigungsprozesse, der Lackierung und des Diskretisierungsgrades auf das Schädigungsverhalten des Materials zu identifizieren. Das IGF-Vorhaben „Methodenentwicklung zur Schädigungsmodellierung für die numerische Prozesssimulation mechanischer Fügeverfahren" der Forschungsvereinigung EFB e.V. wurde unter der Fördernummer AiF 19452N über die Arbeitsgemeinschaft industrieller Forschungsvereinigungen (AiF) im Rahmen des Programms zur Förderung der Industriellen Gemeinschaftsforschung (IGF) vom Bundesministerium für Wirtschaft und Energie aufgrund eines Beschlusses des Deutschen Bundestages gefördert. Der Abschlussbericht ist als EFB-Forschungsbericht Nr. 527 erschienen und bei der EFB-Geschäftsstelle und im Buchhandel erhältlich. AU - Otroshi, Mortaza AU - Meschut, Gerson ID - 20145 SN - 978-3-86776-582-4 TI - Methodenentwicklung zur Schädigungsmodellierung für die numerische Prozesssimulation mechanischer Fügeverfahren ER - TY - CONF AB - Joining technology is regarded as a key technology for reducing energy consumption and CO2 imitation as well as the use of innovative materials and development of new, resource-saving products. Punch riveting is a widely used and established joining process in many sectors. The white and brown goods, electrical engineering, construction and, in particular, the automotive industry are some of the sectors mentioned here. Since the design and assessment of punch rivet components with regard to structural durability can only be carried out experimentally using prototypes due to a lack of experience and calculation concepts, the improvement of this uneconomical and time-consuming procedure is the goal of this contribution. Therefore, a numerical simulation and design method for cyclically loads punched riveted joints shall be introduced. This concept shall be based on the notch strain concept. The following steps are necessary to achieve the goal shown above: Tensile tests on all materials involved in the joint for determination of tensile strength and quasi-static stress-strain curves Estimation of the cyclic material properties from the tensile strength in order to obtain the strain-life curve and the cyclic stress-strain curve Estimation of mean stress sensitivity from the tensile strength to conduct an amplitude transformation for variable amplitude loadings. Execution of a 2D forming simulation of the joining process to determine the geometry and the stresses and degrees of deformation present in the connection Transferring the results of the forming simulation into a static-mechanical load simulation for determining the relation between the external load and the elastic-plastic strain at the critical point Estimation of the service life by means of the damage parameter Wöhler curves calculated from the strain-life curve In order to verify the simulation and calculation method, service life investigations have been carried out on punched riveted components under constant and variable amplitude load. The test results, as well as the workflow through the fatigue assessment and its accuracy in estimation the fatigue life will be shown in this contribution. AU - Masendorf, Lukas AU - Wächter, Michael AU - Horstmann, Stephan AU - Otroshi, Mortaza AU - Esderts, Alfons AU - Meschut, Gerson ID - 20146 KW - punch rivet KW - notch strain conept KW - structural durability SN - 978-3-9820591-0-5 TI - Linear damage accumulation of self-pierce riveted joints ER - TY - CONF AB - Let G = (V,E) be an undirected graph on n vertices with non-negative capacities on its edges. The mincut sensitivity problem for the insertion of an edge is defined as follows. Build a compact data structure for G and a given set S ⊆ V of vertices that, on receiving any edge (x,y) ∈ S×S of positive capacity as query input, can efficiently report the set of all pairs from S× S whose mincut value increases upon insertion of the edge (x,y) to G. The only result that exists for this problem is for a single pair of vertices (Picard and Queyranne, Mathematical Programming Study, 13 (1980), 8-16). We present the following results for the single source and the all-pairs versions of this problem. 1) Single source: Given any designated source vertex s, there exists a data structure of size 𝒪(|S|) that can output all those vertices from S whose mincut value to s increases upon insertion of any given edge. The time taken by the data structure to answer any query is 𝒪(|S|). 2) All-pairs: There exists an 𝒪(|S|²) size data structure that can output all those pairs of vertices from S× S whose mincut value gets increased upon insertion of any given edge. The time taken by the data structure to answer any query is 𝒪(k), where k is the number of pairs of vertices whose mincut increases. For both these versions, we also address the problem of reporting the values of the mincuts upon insertion of any given edge. To derive our results, we use interesting insights into the nearest and the farthest mincuts for a pair of vertices. In addition, a crucial result, that we establish and use in our data structures, is that there exists a directed acyclic graph of 𝒪(n) size that compactly stores the farthest mincuts from all vertices of V to a designated vertex s in the graph. We believe that this result is of independent interest, especially, because it also complements a previously existing result by Hariharan et al. (STOC 2007) that the nearest mincuts from all vertices of V to s is a laminar family, and hence, can be stored compactly in a tree of 𝒪(n) size. AU - Baswana, Surender AU - Gupta, Shiv AU - Knollmann, Till ED - Grandoni, Fabrizio ED - Herman, Grzegorz ED - Sanders, Peter ID - 20159 KW - Mincut KW - Sensitivity KW - Data Structure SN - 1868-8969 T2 - 28th Annual European Symposium on Algorithms (ESA 2020) TI - Mincut Sensitivity Data Structures for the Insertion of an Edge VL - 173 ER - TY - CONF AB - Upcoming sensing applications (acoustic or video) will have high processing requirements not satisfiable by a single node or need input from multiple sources (e.g., speaker localization). Offloading these applications to cloud or mobile edge is an option, but when running in a wireless senor network (WSN), it might entail needlessly high data rate and latency. An alternative is to spread processing inside the WSN, which is particularly attractive if the application comprises individual components. This scenario is typical for applications like acoustic signal processing. Mapping components to nodes can be formulated as wireless version of the NP-hard Virtual Network Embedding (VNE) problem, for which various heuristics exist. We propose a Reinforcement Learning (RL) framework, which relies on Q-Learning and uses either Greedy Epsilon or Epsilon Decay for exploration. We compare both exploration methods to the result of an optimization approach and show empirically that the RL framework achieves good results in terms of network delay within few number of steps. AU - Afifi, Haitham AU - Karl, Holger ID - 20164 T2 - 2020 Thirteenth International Workshop on Selected Topics in Mobile and Wireless Computing (STWiMob'2020) TI - Reinforcement Learning for Virtual Network Embedding in Wireless Sensor Networks ER - TY - CONF AU - Bondarenko, Alexander AU - Fröbe, Maik AU - Beloucif, Meriem AU - Gienapp, Lukas AU - Ajjour, Yamen AU - Panchenko, Alexander AU - Biemann, Chris AU - Stein, Benno AU - Wachsmuth, Henning AU - Potthast, Martin AU - Hagen, Matthias ID - 20166 T2 - CEUR Workshop Proceedings TI - Overview of Touché 2020: Argument Retrieval VL - 2696 ER - TY - JOUR AU - Otroshi, Mortaza AU - Meschut, Gerson ID - 20170 IS - 7/20 JF - Umformtechnik Blech Rohre Profile SN - 0300-3167 TI - Spannungszustandsabhängige Schädigungsmodellierung zum Halbhohlstanznieten ER - TY - CONF AU - Castenow, Jannik AU - Harbig, Jonas AU - Jung, Daniel AU - Knollmann, Till AU - Meyer auf der Heide, Friedhelm ED - Devismes, Stéphane ED - Mittal, Neeraj ID - 20185 SN - 978-3-030-64347-8 T2 - Stabilization, Safety, and Security of Distributed Systems - 22nd International Symposium, SSS 2020, Austin, Texas, USA, November 18-21, 2020, Proceedings TI - Brief Announcement: Gathering in Linear Time: A Closed Chain of Disoriented & Luminous Robots with Limited Visibility VL - 12514 ER - TY - JOUR AB - A dielectric step-index optical fiber with tube-like profile is considered, being positioned with a small gap on top of a dielectric slab waveguide. We propose a 2.5-D hybrid analytical/numerical coupled mode model for the evanescent excitation of the tube through semi-guided waves propagating in the slab at oblique angles. The model combines the directional polarized modes supported by the slab with analytic solutions for the TE-, TM-, and orbital-angular-momentum (OAM) modes of the tube-shaped fiber. Implementational details of the scheme are discussed, complemented by finite-element simulations for verification purposes. Our results include configurations with resonant in-fiber excitation of OAM modes with large orbital angular momentum and strong field enhancement. AU - Hammer, Manfred AU - Ebers, Lena AU - Förstner, Jens ID - 20189 JF - Optical and Quantum Electronics KW - tet_topic_waveguides SN - 0306-8919 TI - Hybrid coupled mode modelling of the evanescent excitation of a dielectric tube by semi-guided waves at oblique angles VL - 52 ER - TY - GEN AU - Hemsen, Paul AU - Hesse, Marc AU - Löken, Nils AU - Nouri, Zahra ID - 20191 T2 - 2nd Crowdworking Symposium TI - Platform-independent Reputation and Qualification System for Crowdwork ER - TY - GEN AB - In many real-world applications, the relative depth of objects in an image is crucial for scene understanding, e.g., to calculate occlusions in augmented reality scenes. Predicting depth in monocular images has recently been tackled using machine learning methods, mainly by treating the problem as a regression task. Yet, being interested in an order relation in the first place, ranking methods suggest themselves as a natural alternative to regression, and indeed, ranking approaches leveraging pairwise comparisons as training information ("object A is closer to the camera than B") have shown promising performance on this problem. In this paper, we elaborate on the use of so-called \emph{listwise} ranking as a generalization of the pairwise approach. Listwise ranking goes beyond pairwise comparisons between objects and considers rankings of arbitrary length as training information. Our approach is based on the Plackett-Luce model, a probability distribution on rankings, which we combine with a state-of-the-art neural network architecture and a sampling strategy to reduce training complexity. An empirical evaluation on benchmark data in a "zero-shot" setting demonstrates the effectiveness of our proposal compared to existing ranking and regression methods. AU - Lienen, Julian AU - Hüllermeier, Eyke ID - 20211 T2 - arXiv:2010.13118 TI - Monocular Depth Estimation via Listwise Ranking using the Plackett-Luce model ER - TY - GEN AU - Yeole, Paresh Kishor ID - 20221 TI - Plurality Consensus in Hybrid Networks ER - TY - JOUR AB - The challenge of designing new tunable nonlinear dielectric materials with tailored properties has attracted an increasing amount of interest recently. Herein, we study the effective nonlinear dielectric response of a stochastic paraelectric-dielectric composite consisting of equilibrium distributions of circular and partially penetrable disks (or parallel, infinitely long, identical, partially penetrable, circular cylinders) of a dielectric phase randomly dispersed in a continuous matrix of a paraelectric phase. The random microstructures were generated using the Metropolis Monte Carlo algorithm. The evaluation of the effective permittivity and tunability were carried out by employing either a Landau thermodynamic model or its Johnson’s approximation to describe the field-dependent permittivity of the paraelectric phase and solving continuum-electrostatics equations using finite element calculations. We reveal that the percolation threshold in this composite governs the critical behavior of the effective permittivity and tunability. For microstructures below the percolation threshold, our simulations demonstrate a strong nonlinear behaviour of the field-dependent effective permittivity and very high tunability that increases as a function of dielectric phase concentration. Above the percolation threshold, the effective permittivity shows the tendency to linearization and the tunability dramatically drops down. The highly reduced permittivity and extraordinarily high tunability are obtained for the composites with dielectric impenetrable disks at high concentrations, in which the triggering of the percolation transition is avoided. The reported results cast light on distinct nonlinear behaviour of 2D and 3D stochastic composites and can guide the design of novel composites with the controlled morphology and tailored permittivity and tunability. AU - Myroshnychenko, Viktor AU - Smirnov, Stanislav AU - Jose, Pious Mathews Mulavarickal AU - Brosseau, Christian AU - Förstner, Jens ID - 20233 JF - Acta Materialia SN - 1359-6454 TI - Nonlinear dielectric properties of random paraelectric-dielectric composites VL - 203 ER - TY - JOUR AU - Heyser, Per AU - Sartisson, Vadim AU - Meschut, Gerson AU - Droß, Marcel AU - Dröder, Klaus ID - 20235 JF - Materials Testing SN - 0025-5300 TI - Increased load bearing capacity of mechanically joined FRP/metal joints using a pin structured auxiliary joining element ER - TY - THES AU - Hoof, Simon ID - 20240 TI - Essays on Cooperation in Differential Games ER - TY - JOUR AU - Böhne, Christoph AU - Meschut, Gerson AU - Biegler, Max AU - Rethmeier, Michael ID - 20269 IS - 7 JF - Science and Technology of Welding and Joining TI - Avoidance of liquid metal embrittlement during resistance spot welding by heat input dependent hold time adaption VL - 25 ER - TY - CONF AU - Biegler, Max AU - Rethmeier, Michael AU - Böhne, Christoph AU - Meschut, Gerson ID - 20273 T2 - Joining in Car Body Engineering TI - Resistance spot welding simulation can determine the critical stress- and strain-conditions leading to liquid metal embrittlement formation ER -