@article{23902, author = {{Grydin, Olexandr and Andreiev, Anatolii and Sotirov, Nikolay and Stolbchenko, Mykhailo and Behr, Teresa M. and Ashkelianets, Anton and Frolov, Iaroslav and Schaper, Mirko}}, issn = {{1047-4838}}, journal = {{JOM}}, pages = {{407--418}}, title = {{{Water Quenching of Hot-Rolled Aluminum Strips: Process Integrated Heat Treatment of the Alloy EN AW-6082}}}, doi = {{10.1007/s11837-018-3144-1}}, year = {{2018}}, } @article{23903, author = {{Lossen, Benjamin and Andreiev, Anatolii and Stolbchenko, Mykhailo and Homberg, Werner and Schaper, Mirko}}, issn = {{0924-0136}}, journal = {{Journal of Materials Processing Technology}}, pages = {{242--250}}, title = {{{Friction-spinning—Grain structure modification and the impact on stress/strain behaviour}}}, doi = {{10.1016/j.jmatprotec.2018.06.015}}, year = {{2018}}, } @article{25911, abstract = {{Different types of reduced graphene oxide and graphene oxide particles have been studied regarding their influence on the curing behaviour of epoxy-amine resins. Especially the specific surface area of reduced graphene oxide was selectively influenced by controlled drying of the material. The different types of reduced graphene oxide particles were used to produce epoxy-amine composites that significantly change their curing behaviour and mechanical properties. A variety of surface areas and compositions were prepared by combination of a fast heating rate and different drying methods. The combination of freeze drying with a fast heating rate leads to a large specific surface area of 680 m2/g. The morphologies of the particles were observed by scanning electron microscope and the BET surface area was measured with nitrogen-physisorption. The exfoliation quality was measured by XRD. The generated graphene oxide and thermally reduced graphene oxide particles were mixed with epoxy-amine resin. The curing behaviour was studied with rheological and differential scanning calorimetry (DSC) measurements. We observed that different surface functionalities lowers the Glass transition temperature and the gel time of an epoxy-amine curing system. In addition, we found that generated graphene oxide acts as flexibilizer. An increase of the deformation from 2.5 mm to 3.1 mm was measured by Erichsen Cupping Test.}}, author = {{Wolk, Andreas and Rosenthal, Marta and Weiß, Julia and Voigt, Markus and Wesendahl, Jan-Niklas and Hartmann, Marc and Grundmeier, Guido and Wilhelm, Rene and Meschut, Gerson and Tiemann, Michael and Bremser, Wolfgang}}, issn = {{0300-9440}}, journal = {{Progress in Organic Coatings}}, pages = {{280--289}}, title = {{{Graphene oxide as flexibilizer for epoxy amine resins}}}, doi = {{10.1016/j.porgcoat.2018.05.028}}, year = {{2018}}, } @article{6571, author = {{Jurgelucks, Benjamin and Claes, Leander and Walther, Andrea and Henning, Bernd}}, issn = {{1055-6788}}, journal = {{Optimization Methods and Software}}, number = {{4-6}}, pages = {{868----888}}, publisher = {{Taylor and Francis Ltd.}}, title = {{{Optimization of triple-ring electrodes on piezoceramic transducers using algorithmic differentiation}}}, doi = {{10.1080/10556788.2018.1435652}}, volume = {{33}}, year = {{2018}}, } @inbook{36478, author = {{Bruns, Julia and Eichen, Lars}}, booktitle = {{Mathematikfortbildungen professionalisieren. Konzepte, Beispiele und Erfahrungen des Deutschen Zentrums für Lehrerbildung Mathematik}}, editor = {{Biehler, Rolf and Lange, Thomas and Leuders, Timo and Rösken-Winter, Bettina}}, pages = {{417--434}}, publisher = {{Springer}}, title = {{{EmMa - Fortbildung für elementarpädagogische Fachpersonen zur frühen mathematischen Bildung}}}, doi = {{10.1007/978-3-658-19028-6_21}}, year = {{2018}}, } @article{46732, author = {{Güldenpenning, Iris and Alhaj Ahmad Alaboud, Mustafa and Kunde, Wilfried and Weigelt, Matthias}}, journal = {{German Journal of Exercise and Sport Research}}, number = {{3}}, pages = {{366–375}}, publisher = {{Springer}}, title = {{{The impact of global and local context information on the processing of deceptive actions in game sports: Both higher head-fake frequencies and head-fake repetitions reduce the size of the head-fake effect in basketball. }}}, doi = {{https://doi.org/10.1007/s12662-018-0493-4}}, volume = {{48}}, year = {{2018}}, } @inproceedings{46910, author = {{Koester, Dirk and Schütz, Christoph and Güldenpenning, Iris and Schack, Thomas}}, booktitle = {{Computational Approaches to Cognitive Science. Proceedings of the 14th Biannual Conference of the German Cognitive Science Society (KOGWIS) }}, editor = {{Rothkopf, C. and Balfanz, D. and Galuske, R. and Jäkel, F. and Kersting, K. and Macke, J. and Mohler, B.}}, location = {{Darmstadt}}, pages = {{30}}, title = {{{What does the EEG reveal about how athletes process head fakes in basketball?}}}, year = {{2018}}, } @article{42716, abstract = {{Die Vereinbarkeit einer erfolgreichen Bildungs- und Leistungssportkarriere steht immer wieder zur Diskussion. Mit dem Ziel die Doppelbelastung aus Schule und Sport abzupuffern und gleichzeitig eine positive Entwicklung der Sportler*innen zu fördern, werden in NRW seit 2006 Sportschulen eingerichtet. Die Ergebnisse einer Studie an einer solchen Realschule belegen, dass die sportlichen Heranwachsenden hinsichtlich der Bildungskarriere im Untersuchungszeitraum nicht benachteiligt sind.}}, author = {{Kehne, Miriam and Breithecker, Jennifer and Strotmeyer, Anne}}, journal = {{Sportunterricht}}, number = {{10}}, pages = {{446--450}}, title = {{{NRW-Sportschule: Sportliche Leistung fördern - schulische Ausbildung sichern}}}, volume = {{67}}, year = {{2018}}, } @inproceedings{46906, author = {{Koester, Dirk and Schütz, Christoph and Güldenpenning, Iris and Schack, Thomas}}, booktitle = {{Die Psychophysiologie der Handlung. Abstractband der 50. Jahrestagung der Arbeitsgemeinschaft für Sportpsychologie (asp)}}, editor = {{Borges, U. and Bröker, L. and Hoffmann, S. and Hosang, T.J. and Laborde, S. and Liepelt, R. and Lobinger, B. and Löffler, J. and Musculus, L. and Raab, M.}}, location = {{Köln}}, pages = {{33--34}}, title = {{{Wie verarbeiten Basketball-Athleten Blickfinten? Eine EEG-Studie}}}, year = {{2018}}, } @inproceedings{47007, author = {{Polzien, A. and Güldenpenning, Iris and Weigelt, Matthias}}, booktitle = {{Die Psychophysiologie der Handlung. Abstractband der 50. Jahrestagung der Arbeitsgemeinschaft für Sportpsychologie (asp)}}, editor = {{Borges, U. and Bröker, L. and Hoffmann, S. and Hosang, T. and Laborde, S. and Liepelt, R. and Lobinger, B. and Löffler, J. and Musculus, L. and Raab, M.}}, location = {{Köln}}, pages = {{29}}, title = {{{Effektorspezifische Bahnungsprozesse bei der Handlungsbeobachtung im Kampfsport}}}, year = {{2018}}, } @inproceedings{47005, author = {{Polzien, A. and Güldenpenning, Iris and Weigelt, Matthias}}, booktitle = {{Abstracts of the 60th Conference of Experimental Psychologists (TeaP)}}, editor = {{Schütz, A. C. and Schubö, A. and Endres, D. and Lachnit, H.}}, location = {{Marburg}}, pages = {{201}}, publisher = {{Pabst Science Publishers}}, title = {{{Effector priming during action observation in combat sports}}}, year = {{2018}}, } @article{19943, abstract = {{In this paper we continue our study of bifurcations of solutions of boundary-value problems for symplectic maps arising as Hamiltonian diffeomorphisms. These have been shown to be connected to catastrophe theory via generating functions and ordinary and reversal phase space symmetries have been considered. Here we present a convenient, coordinate free framework to analyse separated Lagrangian boundary value problems which include classical Dirichlet, Neumann and Robin boundary value problems. The framework is then used to prove the existence of obstructions arising from conformal symplectic symmetries on the bifurcation behaviour of solutions to Hamiltonian boundary value problems. Under non-degeneracy conditions, a group action by conformal symplectic symmetries has the effect that the flow map cannot degenerate in a direction which is tangential to the action. This imposes restrictions on which singularities can occur in boundary value problems. Our results generalise classical results about conjugate loci on Riemannian manifolds to a large class of Hamiltonian boundary value problems with, for example, scaling symmetries. }}, author = {{McLachlan, Robert I and Offen, Christian}}, journal = {{New Zealand Journal of Mathematics}}, keywords = {{Hamiltonian boundary value problems, singularities, conformal symplectic geometry, catastrophe theory, conjugate loci}}, pages = {{83--99}}, title = {{{Hamiltonian boundary value problems, conformal symplectic symmetries, and conjugate loci}}}, doi = {{10.53733/34 }}, volume = {{48}}, year = {{2018}}, } @inproceedings{1588, abstract = {{The exploration of FPGAs as accelerators for scientific simulations has so far mostly been focused on small kernels of methods working on regular data structures, for example in the form of stencil computations for finite difference methods. In computational sciences, often more advanced methods are employed that promise better stability, convergence, locality and scaling. Unstructured meshes are shown to be more effective and more accurate, compared to regular grids, in representing computation domains of various shapes. Using unstructured meshes, the discontinuous Galerkin method preserves the ability to perform explicit local update operations for simulations in the time domain. In this work, we investigate FPGAs as target platform for an implementation of the nodal discontinuous Galerkin method to find time-domain solutions of Maxwell's equations in an unstructured mesh. When maximizing data reuse and fitting constant coefficients into suitably partitioned on-chip memory, high computational intensity allows us to implement and feed wide data paths with hundreds of floating point operators. By decoupling off-chip memory accesses from the computations, high memory bandwidth can be sustained, even for the irregular access pattern required by parts of the application. Using the Intel/Altera OpenCL SDK for FPGAs, we present different implementation variants for different polynomial orders of the method. In different phases of the algorithm, either computational or bandwidth limits of the Arria 10 platform are almost reached, thus outperforming a highly multithreaded CPU implementation by around 2x.}}, author = {{Kenter, Tobias and Mahale, Gopinath and Alhaddad, Samer and Grynko, Yevgen and Schmitt, Christian and Afzal, Ayesha and Hannig, Frank and Förstner, Jens and Plessl, Christian}}, booktitle = {{Proc. Int. Symp. on Field-Programmable Custom Computing Machines (FCCM)}}, keywords = {{tet_topic_hpc}}, publisher = {{IEEE}}, title = {{{OpenCL-based FPGA Design to Accelerate the Nodal Discontinuous Galerkin Method for Unstructured Meshes}}}, doi = {{10.1109/FCCM.2018.00037}}, year = {{2018}}, } @inproceedings{1590, abstract = {{We present the submatrix method, a highly parallelizable method for the approximate calculation of inverse p-th roots of large sparse symmetric matrices which are required in different scientific applications. Following the idea of Approximate Computing, we allow imprecision in the final result in order to utilize the sparsity of the input matrix and to allow massively parallel execution. For an n x n matrix, the proposed algorithm allows to distribute the calculations over n nodes with only little communication overhead. The result matrix exhibits the same sparsity pattern as the input matrix, allowing for efficient reuse of allocated data structures. We evaluate the algorithm with respect to the error that it introduces into calculated results, as well as its performance and scalability. We demonstrate that the error is relatively limited for well-conditioned matrices and that results are still valuable for error-resilient applications like preconditioning even for ill-conditioned matrices. We discuss the execution time and scaling of the algorithm on a theoretical level and present a distributed implementation of the algorithm using MPI and OpenMP. We demonstrate the scalability of this implementation by running it on a high-performance compute cluster comprised of 1024 CPU cores, showing a speedup of 665x compared to single-threaded execution.}}, author = {{Lass, Michael and Mohr, Stephan and Wiebeler, Hendrik and Kühne, Thomas and Plessl, Christian}}, booktitle = {{Proc. Platform for Advanced Scientific Computing (PASC) Conference}}, isbn = {{978-1-4503-5891-0/18/07}}, keywords = {{approximate computing, linear algebra, matrix inversion, matrix p-th roots, numeric algorithm, parallel computing}}, location = {{Basel, Switzerland}}, publisher = {{ACM}}, title = {{{A Massively Parallel Algorithm for the Approximate Calculation of Inverse p-th Roots of Large Sparse Matrices}}}, doi = {{10.1145/3218176.3218231}}, year = {{2018}}, } @inproceedings{1204, author = {{Riebler, Heinrich and Vaz, Gavin Francis and Kenter, Tobias and Plessl, Christian}}, booktitle = {{Proc. ACM SIGPLAN Symposium on Principles and Practice of Parallel Programming (PPoPP)}}, isbn = {{9781450349826}}, keywords = {{htrop}}, publisher = {{ACM}}, title = {{{Automated Code Acceleration Targeting Heterogeneous OpenCL Devices}}}, doi = {{10.1145/3178487.3178534}}, year = {{2018}}, } @inbook{56342, author = {{Kokew, Stephan Matthias}}, booktitle = {{Diversität historisch. Repräsentationen und Praktiken gesellschaftlicher Differenzierung im Wandel}}, editor = {{Florin, Moritz and Gutsche, Victoria and Krentz, Natalie}}, isbn = {{9783839444016}}, pages = {{193--209}}, title = {{{Islamische Konzeptionen zum Umgang mit religiöser Diversität: Zarathustrier und Buddhisten}}}, doi = {{10.1515/9783839444016-010}}, year = {{2018}}, } @inbook{56343, author = {{Kokew, Stephan Matthias}}, booktitle = {{Islamisches Recht in Wissenschaft und Praxis. Festschrift für Hans-Georg Ebert}}, editor = {{Elliesie, Hatem and Anam, Beate and Hanstein, Thoralf}}, pages = {{329--345}}, title = {{{Überlegungen zum Prinzip der Schutzverpflichtung als Bestandteil islamischer Schutzgewährung}}}, doi = {{10.3726/b15031}}, year = {{2018}}, } @article{59979, abstract = {{Currently, it is state of the art to use precipitation hardening 6000-series aluminum alloys to manufacture high-strength aluminum automotive parts by extrusion or in a cold forming process. Alternatively, it is also possible to produce such parts by the use of non-precipitation hardening 5000-series aluminum alloys in a work-hardened condition. Therefore, BENTELER Automobiltechnik GmbH developed a special sheet forming process, henceforth referred to as "flash forming process". The application of the flash forming process, consisting of a rapid heat treatment and a subsequent cold die stamping, increases the forming capability of the work-hardened 5000-series aluminum sheets and results in high-strength parts with a very good ductility and weldability. In addition, this thermal assisted forming process allows a cost-saving production of such high-strength aluminum parts due to lower material costs of 5000-series aluminum alloys than those of a 6000-series material. Furthermore, the weight-saving effects of "flash formed" parts can be higher compared to extruded or cold formed 6000-series aluminum alloys. The suitability of the process is evaluated by forming a commercial AW-5182 H18 aluminum sheet to a crash-relevant automotive part. However, to accurately simulate the flash forming process itself, a temperature dependent fracture model is necessary. Investigations on a coupon basis also showed that the effect of adiabatic heating due to plastic work cannot be neglected. In cooperation with Paderborn University, a detailed mechanical testing, aided by digital image correlation (DIC) and thermal imaging, is carried out to characterize the yield, hardening and fracture behavior at elevated temperatures. The experimental tests are followed by the calibration of a FLD and an incremental stress state dependent fracture model in LS-DYNA. Finally, the simulation models are validated on a cross die deep drawn cup.}}, author = {{Camberg, A A and Bohner, F and Tölle, J and Schneidt, A and Meiners, S and Tröster, Thomas}}, issn = {{1757-899X}}, journal = {{IOP Conference Series: Materials Science and Engineering}}, publisher = {{IOP Publishing}}, title = {{{Formability enhancement of EN AW-5182 H18 aluminum alloy sheet metal parts in a flash forming process: testing, calibration and evaluation of fracture models}}}, doi = {{10.1088/1757-899x/418/1/012018}}, volume = {{418}}, year = {{2018}}, } @inproceedings{16048, author = {{Ahlers, Dominik and Tröster, Thomas and Hermann, S. and Koppa, P. and Gloetter, P. and Schaper, Mirko and Peters, M. and Burns, M. and Hengsbach, Florian and Altmann, A.}}, booktitle = {{Contributed Papers from MS&T17}}, isbn = {{9780873397667}}, title = {{{Selective Laser Melting of Ti6Al4V with High Build Rates and Following Hot Isostatic Pressing}}}, doi = {{10.7449/2018mst/2018/mst_2018_117_124}}, year = {{2018}}, } @inproceedings{15960, author = {{Weiß-Borkowski, Nathalie and Lian, Junhe and Camberg, Alan Adam and Tröster, Thomas and Münstermann, Sebastian and Bleck, Wolfgang and Gese, Helmut and Richter, Helmut}}, title = {{{Forming limit curves of DP600 determined in high-speed Nakajima tests and predicted by two different strain-rate-sensitive models}}}, doi = {{10.1063/1.5035024}}, year = {{2018}}, }