TY - CHAP AU - Ganguin, S. AU - Meister, Dorothee M. ED - Ganguin, S. ED - Meister, Dorothee M. ID - 18092 T2 - Digital native oder digital naiv? Medienpädagogik der Generationen TI - Medienpädagogik der Generation - Einführende Überlegungen ER - TY - JOUR AB - We present recent advances in numerical implementations of hybrid functionals and the GW approximation within the full-potential linearized augmented-plane-wave (FLAPW) method. The former is an approximation for the exchange–correlation contribution to the total energy functional in density-functional theory, and the latter is an approximation for the electronic self-energy in the framework of many-body perturbation theory. All implementations employ the mixed product basis, which has evolved into a versatile basis for the products of wave functions, describing the incoming and outgoing states of an electron that is scattered by interacting with another electron. It can thus be used for representing the nonlocal potential in hybrid functionals as well as the screened interaction and related quantities in GW calculations. In particular, the six-dimensional space integrals of the Hamiltonian exchange matrix elements (and exchange self-energy) decompose into sums over vector–matrix–vector products, which can be evaluated easily. The correlation part of the GW self-energy, which contains a time or frequency dependence, is calculated on the imaginary frequency axis with a subsequent analytic continuation to the real axis or, alternatively, by a direct frequency convolution of the Green function G and the dynamically screened Coulomb interaction W along a contour integration path that avoids the poles of the Green function. Hybrid-functional and GW calculations are notoriously computationally expensive. We present a number of tricks that reduce the computational cost considerably, including the use of spatial and time-reversal symmetries, modifications of the mixed product basis with the aim to optimize it for the correlation self-energy and another modification that makes the Coulomb matrix sparse, analytic expansions of the interaction potentials around the point of divergence at k=0, and a nested density and density-matrix convergence scheme for hybrid-functional calculations. We show CPU timings for prototype semiconductors and illustrative results for GdN and ZnO. AU - Friedrich, Christoph AU - Betzinger, Markus AU - Schlipf, Martin AU - Blügel, Stefan AU - Schindlmayr, Arno ID - 18542 IS - 29 JF - Journal of Physics: Condensed Matter SN - 0953-8984 TI - Hybrid functionals and GW approximation in the FLAPW method VL - 24 ER - TY - CONF AB - The quality of laser sintered parts, in this work, manufactured by polymer laser sintering by using an EOSINT P395 Laser Sintering system, depends on several steps along the process chain. The first step is the characterization of the powder quality, whereas the rheological and physical investigations of nylon 12 powder are shown. By changing some important influencing factors, for example the powder ratio, the powder ageing and the moisture content, the influence on mechanical and physical properties, density and porosity, are investigated. The composition of the used powder is known. The previous process (storage conditions, etc.) as well as the laser sintering process (regarding energy density, temperature, etc.) is kept constant for the duration of this work. Regarding the post process in this work the cooling down phase is investigated as well. With an automatically blasting system it is possible to keep the post process parameters blasting distance and blasting time, constant. All of the tests will be performed using dry and conditioned test specimens. This work is showing the dependence on mechanical, rheological and physical parameters by varying important influencing factors along the laser sintering process quality chain. AU - Rüsenberg, Stefan AU - Weiffen, R. AU - Knoop, F. AU - Schmid, Hans-Joachim ID - 22174 T2 - 23rd Annual International Solid Freeform Fabrication Symposium TI - Controlling the Quality of Laser Sintered Parts Along the Process Chain VL - 23 ER - TY - CONF AB - Material properties of parts from additive manufacturing are influenced by a huge number of material, operational and job parameters. This work aims to identify the most important ones and to investigate mechanical properties as depending on those parameters. Test specimens were produced with standard PA12 powder on an EOSINT P390 and P395, respectively. The influence of the orientation and placement of parts in the building chamber were investigated systematically. The mechanical properties AU - Rüsenberg, Stefan AU - Schmid, Hans-Joachim ID - 22204 T2 - The European Forum on Additive Manufacturing TI - Mechanical Properties as a Result of multitude of Parameters VL - 17 ER - TY - CONF AU - Adam, Guido AU - Zimmer, Detmar ID - 22364 TI - Elementbasierte Erarbeitung von Konstruktionsregeln für additive Fertigung ER - TY - JOUR AU - Zimmer, Detmar AU - Lessmeier, Christian AU - Hameyer, Kay AU - Piantsop Mbo'o, Christelle AU - Coenen, Isabel ID - 22365 JF - ant Journal - Anwendungsnahe Forschung für Antriebstechnik im Maschinenbau TI - Untersuchung von Bauteilschäden elektrischer Antriebsstränge im Belastungsprüfstand mittels Statorstromanalyse VL - 1 ER - TY - CONF AU - Kriegel, Nils-Peter AU - Wecker, Markus AU - Zimmer, Detmar ID - 22366 T2 - VDI-Konferenz Innovative Bremstechnik TI - Anforderungen an Bremssysteme in der industriellen Antriebstechnik VL - 2 ER - TY - BOOK AU - Lessmeier, Christian AU - Piantsop Mbo'o, Christelle AU - Coenen, Isabel AU - Zimmer, Detmar AU - Hameyer, Kay ID - 22367 SN - 978-3-941277-17-5 TI - Untersuchung von Bauteilschäden elektrischer Antriebsstränge im Belastungsprüfstand mittels Statorstromanalyse VL - 81 ER - TY - JOUR AU - Kriegel, Nils-Peter AU - Zimmer, Detmar ID - 22368 JF - Newsletter der Wissenschaftlichen Gesellschaft für Produktentwicklung SN - 1613-5504 TI - Anforderungen an Bremssysteme der industriellen Antriebstechnik VL - 2 ER - TY - CONF AU - Nolte, Karsten AU - Zimmer, Detmar ID - 22369 T2 - International Sealing Conference TI - Low friction Rotary Shaft Seal. Verlustleistungsreduziertes Dichtsystem VL - 17 ER - TY - CONF AU - Hölscher, Christian AU - Zimmer, Detmar AU - Keßler, Jan Henning AU - Kruger, Martin AU - Trächtler, Ansgar ID - 22370 SN - 978-1-467303-12-5 T2 - IEEE International Conference on Industrial Informatics TI - Hierarchical optimization of coupled self-optimizing systems VL - 10 ER - TY - CONF AU - Fiekens, Nicolas AU - Zimmer, Detmar AU - Michaelis, Stefanie AU - Schöppner, Volker AU - Hallmann, Tobias ID - 22371 T2 - DKT 2012. Deutsche Kautschuk Tagung TI - Entwicklung eines modularen Antriebssystems für Kautschukinnenmischer ER - TY - BOOK AU - Zimmer, Detmar ID - 22372 SN - 978-3-446-43000-6 TI - Elektromechanische Antriebe ER - TY - GEN AB - The phenomenon that groups or people work together when they face an opponent, although they have little in common otherwise, has been termed the "common enemy effect". We study a model of network formation, where players can use links to build a network, knowing that they are facing a common enemy who can disrupt the links within the network, and whose goal it is to minimize the sum of the benefits of the network. We find that introducing a common enemy can lead to the formation of stable and efficient networks as well as fragmented networks and the empty network. AU - Hoyer, Britta AU - De Jaegher, Kris ID - 2249 TI - Network Disruption and the Common Enemy Effect VL - 12-06 ER - TY - CONF AU - Becker, Matthias AU - Luckey, Markus AU - Becker, Steffen ID - 22737 KW - model-driven performance engineering KW - self-* KW - Self-adaptation KW - software performance SN - 978-1-4503-1346-9 T2 - {Proceedings of the 8th International ACM SIGSOFT Conference on Quality of Software Architectures (QoSA)} TI - Model-driven Performance Engineering of Self-adaptive Systems: A Survey ER - TY - JOUR AU - Gries, Thomas AU - Prior, Ulrich AU - Sureth-Sloane, Caren ID - 22920 IS - 3 JF - Journal of Public Economic Theory TI - A Tax Paradox for Investment Decisions under Uncertainty VL - 14 ER - TY - JOUR AU - Yildirim, Ömer AU - Kiss, Anton A. AU - Hüser, Nicole AU - Leßmann, Katharina AU - Kenig, Eugeny ID - 22929 JF - Chemical Engineering Journal SN - 1385-8947 TI - Reactive absorption in chemical process industry: A review on current activities ER - TY - CONF AU - Low, Cheng AU - Aldemir, Mustafa AU - Aziz, Norheliena AU - Dumitrescu, Roman AU - Anacker, Harald ID - 22936 T2 - Proceedings of the 1st German-Malaysian Workshop, Hannover, 27. - 29. Jun. 2012 TI - Strategy Planning of Collaborative Humanoid Soccer Robots based on Principle Solution ER - TY - CONF AU - Bauer, Frank AU - Gausemeier, Jürgen AU - Köchling, Daniel AU - Oestersötebier, Felix ID - 23150 T2 - Tag des Systems Engineerings TI - Simulative Absicherung mechatronischer Systeme in der frühen Phase der Produktentstehung ER - TY - CONF AU - Oestersötebier, Felix AU - Dziwok, Stefan AU - Bauer, Frank AU - Trächtler, Ansgar AU - Schäfer, Wilhelm AU - Gausemeier, Jürgen ID - 23151 T2 - Tag des Systems Engineerings TI - Unterstützung des mechatronischen Entwurfs durch die effektive Suche nach Lösungselementen mithilfe von semantischen Technologien ER -