@inproceedings{15987, author = {{Lauter, Christian and Frantz, Meike and Kohler, J. P. and Tröster, Thomas}}, location = {{Venice, Italy}}, title = {{{Crash tests of hybrid structures consisting of sheet metal and local CFRP reinforcements}}}, year = {{2012}}, } @inproceedings{15988, author = {{Lauter, Christian and Sarrazin, M. and Tröster, Thomas}}, location = {{Porto, Portugal}}, title = {{{Joining technologies for hybrid materials consisting of sheet metal and carbon fibre reinforced plastics}}}, year = {{2012}}, } @article{15989, author = {{Ickert, Leif and Thomas, Dieter and Tröster, Thomas and Eckstein, Lutz}}, issn = {{2192-7863}}, journal = {{FAT-Schriftenreihe 244}}, number = {{244}}, publisher = {{Forschungsvereinigung Automobiltechnik e.V.}}, title = {{{Beitrag zum Fortschritt im Automobilleichtbau durch belastungsgerechte Gestaltung und innovative Lösungen für lokale Verstärkungen von Fahrzeugstrukturen in Mischbauweise}}}, year = {{2012}}, } @inproceedings{16004, author = {{Lauter, Christian and Siewers, Bernd and Zanft, B. and Tröster, Thomas}}, location = {{Porto }}, title = {{{Crash worthiness of hybrid pillar structures consisting of sheet metal and local CFRP reinforcements}}}, year = {{2012}}, } @inproceedings{16007, author = {{Thöne, M. and Leuders, S. and Riemer, A. and Tröster, Thomas and Richard, H. A.}}, location = {{Austin, Texas, USA}}, title = {{{Influence of heat-treatment on Selective Laser Melting products - e.g. Ti6Al4V}}}, year = {{2012}}, } @article{16008, author = {{Riemer, A. and Leuders, S. and Tröster, Thomas and Richard, H. A.}}, journal = {{DVM-Bericht 139, Werkstoffe und Fügeverfahren - Neue Herausforderungen für die Betriebsfestigkeit}}, publisher = {{Deutscher Verband für Materialforschung und -prüfung e.V.}}, title = {{{Untersuchung zyklisch belasteter SLM-Bauteile aus der Titan-Aluminium-Legierung TiAl6V4}}}, year = {{2012}}, } @inproceedings{16009, author = {{Leuders, S. and Riemer, A. and Tröster, Thomas and Richard, H. A.}}, location = {{Kassel}}, title = {{{Characterization and Comparison of Mechanical Properties of SLM Materials with Regard to Process Cycle Time Improvement}}}, year = {{2012}}, } @article{16015, author = {{Leuders, S. and Thöne, M. and Riemer, A. and Niendorf, T. and Tröster, Thomas and Richard, H.A. and Maier, H.J.}}, issn = {{0142-1123}}, journal = {{International Journal of Fatigue}}, pages = {{300--307}}, title = {{{On the mechanical behaviour of titanium alloy TiAl6V4 manufactured by selective laser melting: Fatigue resistance and crack growth performance}}}, doi = {{10.1016/j.ijfatigue.2012.11.011}}, year = {{2012}}, } @inproceedings{22164, abstract = {{Generative production techniques have the advantage of manufacturing parts via an additive process without needing a forming tool. One of these additive manufacturing technologies is "Fused Deposition Modeling" (FDM). It is one of the most used additive manufacturing processes to produce prototypes and end-use parts. From a 3D-CAD data set, components and assemblies are manufactured out of thermoplastic material layer by layer by means of an additive process. An extrusion head deposits the molten thermoplastic filament to create each layer with a particular tool path. Due to the thermal fusion the material bonds with the layer beneath and solidifies. Thus a permanent bonding of two layers is formed. In this paper the mechanical data of parts, manufactured with the system Fortus 400mc from Stratasys with the material Ultem*9085 are presented. Tensile and flexural tests according to both, the ASTM and the ISO standard, are conducted. Test specimens are generated with the standard parameters of the native software in different build directions. The tests show different strength and strain characteristics that depend on the given structure as a result of the build direction. Furthermore tensile specimens according to the ASTM standard are generated with changed parameters of the native software to increase the mechanical strength properties. The results are compared to injection molded strength properties.}}, author = {{Bagsik, A. and Schöppner, Volker and Klemp, E.}}, booktitle = {{1st International Conference on Thermo-Mechanically Graded Materials}}, isbn = {{9783942267588}}, pages = {{129--134}}, title = {{{Tensile and Flexural Properties of Fused Deposition Modeling Parts Manufactured with ULTEM*9085}}}, volume = {{1}}, year = {{2012}}, } @inproceedings{22024, abstract = {{Generative production techniques have the advantage of manufacturing parts via an additive process without needing a forming tool. One of these additive manufacturing technologies is “Fused Deposition Modeling” (FDM). It is one of the most used additive manufacturing processes to produce prototypes and end-use parts. From a 3D-CAD data set, components and assemblies are manufactured out of thermoplastic material layer by layer by means of an additive process. An extrusion head deposits the molten thermoplastic filament to create each layer with a particular tool path. In this paper the mechanical data of parts, manufactured with the system Fortus 400mc from Stratasys with the material Ultem*9085 are presented. Tensile specimens are generated with the standard parameters as well as with changed parameters of the native software to analyze the influence of these parameters on the mechanical strength properties. The tensile tests show different strength and strain characteristics that depend on the given structure and as a result of the build direction. Furthermore the toolpath parameters have an effect on the strength characteristics and the break behavior. In addition, tensile specimens are tested under the influence of different temperatures and after a thermal cycling. }}, author = {{Bagsik, A. and Schöppner, Volker and Klemp, E.}}, booktitle = {{5th International Conference on Polymer and Mould Innovations}}, pages = {{266--272}}, publisher = {{Centre for Polymer and Material Technology, Univ. College, Ghent Univ.}}, title = {{{Extensive Analysis of the mechanical strength properties of Fused Deposition Modeling Parts manufactured with ULTEM 9085}}}, doi = {{https://www.tib.eu/de/suchen/id/TIBKAT%3A756276616}}, volume = {{5}}, year = {{2012}}, } @inproceedings{34718, author = {{Behrent, Sigrid and Lorenz, Gunter}}, booktitle = {{Excellent und initiativ. Qualitätsentwicklung und -sicherung in der Sprachausbildung an Hochschulen. Dokumentation der 26. Arbeitstagung 2010.}}, editor = {{Reich, Astrid and Spänkuch, Enke}}, location = {{Bochum}}, pages = {{59--68}}, publisher = {{AKS-Verlag}}, title = {{{Lifelong Learning - auch für Lehrkräfte?! Angebote zur Fort- und Weiterbildung an Sprachenzentren}}}, volume = {{12}}, year = {{2012}}, } @article{31300, author = {{Potzuweit, A. and Weich, Tobias and Barkhofen, Sonja and Kuhl, U. and Stöckmann, H.-J. and Zworski, M.}}, issn = {{1539-3755}}, journal = {{Physical Review E}}, keywords = {{Industrial and Manufacturing Engineering, Metals and Alloys, Strategy and Management, Mechanical Engineering}}, number = {{6}}, publisher = {{American Physical Society (APS)}}, title = {{{Weyl asymptotics: From closed to open systems}}}, doi = {{10.1103/physreve.86.066205}}, volume = {{86}}, year = {{2012}}, } @inproceedings{65968, author = {{Dziwok, Stefan and Heinzemann, Christian and Tichy, Matthias}}, booktitle = {{Proceedings of the 14th International Conference on Coordination Languages and Models (COORDINATION 2012), IFIP International Federation for Information Processing (2012)}}, editor = {{Sirjani, Marjan}}, pages = {{166–180}}, title = {{{Real-Time Coordination Patterns for Advanced Mechatronic Systems}}}, year = {{2012}}, } @phdthesis{19619, author = {{Korzeniowski, Miroslaw}}, isbn = {{978-3-942647-08-3}}, publisher = {{Verlagsschriftenreihe des Heinz Nixdorf Instituts, Paderborn}}, title = {{{Dynamic Load Balancing in Peer-to-Peer Networks}}}, volume = {{289}}, year = {{2011}}, } @inproceedings{1968, abstract = {{Infrastructure as a Service providers use virtualization to abstract their hardware and to create a dynamic data center. Virtualization enables the consolidation of virtual machines as well as the migration of them to other hosts during runtime. Each provider has its own strategy to efficiently operate a data center. We present a rule based mapping algorithm for VMs, which is able to automatically adapt the mapping between VMs and physical hosts. It offers an interface where policies can be defined and combined in a generic way. The algorithm performs the initial mapping at request time as well as a remapping during runtime. It deals with policy and infrastructure changes. We extended the open source IaaS solution Eucalyptus and we evaluated it with typical policies: maximizing the compute performance and VM locality to achieve a high performance and minimizing energy consumption. The evaluation was done on state-of-the-art servers in our own data center and by simulations using a workload of the Parallel Workload Archive. The results show that our algorithm performs well in dynamic data centers environments.}}, author = {{Kleineweber, Christoph and Keller, Axel and Niehörster, Oliver and Brinkmann, André}}, booktitle = {{Proc. Int. Conf. on Parallel, Distributed and Network-Based Computing (PDP)}}, title = {{{Rule Based Mapping of Virtual Machines in Clouds}}}, doi = {{10.1109/PDP.2011.69}}, year = {{2011}}, } @article{1971, abstract = {{System virtualization has become the enabling technology to manage the increasing number of different applications inside data centers. The abstraction from the underlying hardware and the provision of multiple virtual machines (VM) on a single physical server have led to a consolidation and more efficient usage of physical servers. The abstraction from the hardware also eases the provision of applications on different data centers, as applied in several cloud computing environments. In this case, the application need not adapt to the environment of the cloud computing provider, but can travel around with its own VM image, including its own operating system and libraries. System virtualization and cloud computing could also be very attractive in the context of high‐performance computing (HPC). Today, HPC centers have to cope with both, the management of the infrastructure and also the applications. Virtualization technology would enable these centers to focus on the infrastructure, while the users, collaborating inside their virtual organizations (VOs), would be able to provide the software. Nevertheless, there seems to be a contradiction between HPC and cloud computing, as there are very few successful approaches to virtualize HPC centers. This work discusses the underlying reasons, including the management and performance, and presents solutions to overcome the contradiction, including a set of new libraries. The viability of the presented approach is shown based on evaluating a selected parallel, scientific application in a virtualized HPC environment. }}, author = {{Birkenheuer, Georg and Brinkmann, André and Kaiser, Jürgen and Keller, Axel and Keller, Matthias and Kleineweber, Christoph and Konersmann, Christoph and Niehörster, Oliver and Schäfer, Thorsten and Simon, Jens and Wilhelm, Maximilan}}, journal = {{Software: Practice and Experience}}, publisher = {{John Wiley & Sons}}, title = {{{Virtualized HPC: a contradiction in terms?}}}, doi = {{10.1002/spe.1055}}, year = {{2011}}, } @inproceedings{1972, abstract = {{We present a multi-agent system on top of the IaaS layer consisting of a scheduler agent and multiple worker agents. Each job is controlled by an autonomous worker agent, which is equipped with application specific knowledge (e.g., performance functions) allowing it to estimate the type and number of necessary resources. During runtime, the worker agent monitors the job and adapts its resources to ensure the specified quality of service - even in noisy clouds where the job instances are influenced by other jobs. All worker agents interact with the scheduler agent, which takes care of limited resources and does a cost-aware scheduling by assigning jobs to times with low energy costs. The whole architecture is self-optimizing and able to use public or private clouds.}}, author = {{Niehörster, Oliver and Keller, Axel and Brinkmann, André}}, booktitle = {{Proc. Int. Meeting of the IEEE Int. Symp. on Modeling, Analysis and Simulation of Computer and Telecommunication Systems (MASCOTS)}}, title = {{{An Energy-Aware SaaS Stack}}}, doi = {{10.1109/MASCOTS.2011.52}}, year = {{2011}}, } @inproceedings{19845, abstract = {{In dieser Arbeit stellen wir ein flexibles System zur Entwicklung und Evaluation von 3-D-Renderingalgorithmen vor, das die Visualisierung komplexer virtueller Szenen auf einem breiten Spektrum an Geräten erlaubt. Die Aufbereitung und Echtzeitdarstellung solcher virtueller Szenen, wie sie beispielsweise aus detaillierten CAD-Daten erzeugt werden, stellt in vielerlei Hinsicht eine algorithmische und technische Herausforderung dar. Die 3-D-Szenendaten können nach dem Dateiimport aus einem Austauschformat in eine Vielzahl unterschiedlicher Datenstrukturen überführt werden. Es muss ein geeignetes Renderingverfahren ausgewählt und eingestellt werden, welches sowohl die Eigenschaften der Szene (Zahl der Polygone, Grad der Verdeckung etc.) als auch die Fähigkeiten der Hardware berücksichtigt. Auf der einen Seite stellt die Darstellung auf mobilen Endgeräten wie Smartphones besonders hohe Anforderungen aufgrund der Speicherbeschränkung und der geringen Leistungsfähigkeit der Grafikhardware. Auf der anderen Seite stehen bei Großprojektionssystemen, wie beispielsweise dem HD-Visualisierungscenter des Heinz Nixdorf Instituts, die hohe Bildqualität bei stereoskopischer Darstellung und die Unterstützung von Trackingsystemen im Vordergrund. Der Fokus des von uns entwickelten Systems PADrend liegt in der Bereitstellung einer flexiblen und leicht erweiterbaren Grundlage für die Entwicklung und Evaluation von 3-D-Renderingalgorithmen und räumlichen Datenstrukturen im Bereich der Forschung und der universitären Ausbildung. Durch den modularen Aufbau und die große Bandbreite an unterstützten Systemen wird gewährleistet, dass eine Vielzahl unterschiedlicher Entwicklungen und Anwendungen auf PADrend aufsetzen können. In diesem Artikel geben wir einen Überblick über den Aufbau und die Fähigkeiten des Systems. Des Weiteren geben wir ein Beispiel für ein Anwendungsszenario, in dem PADrend eingesetzt wird: die Visualisierung von architektonischen Modellen auf einem Multiprojektionssystem.}}, author = {{Jähn, Claudius and Petring, Ralf and Eikel, Benjamin}}, booktitle = {{Augmented & Virtual Reality in der Produktentstehung}}, pages = {{159----170}}, publisher = {{Verlagsschriftenreihe des Heinz Nixdorf Instituts, Paderborn}}, title = {{{PADrend: Platform for Algorithm Development and Rendering}}}, volume = {{295}}, year = {{2011}}, } @book{25878, author = {{Aufenanger, Mark}}, publisher = {{Verlagsschriftenreihe des Heinz Nixdorf Instituts, Paderborn}}, title = {{{Situativ trainierte Regeln zur Ablaufsteuerung in Fertigungssystemen und ihre Integration in Simulationssysteme}}}, volume = {{269}}, year = {{2011}}, } @book{26185, author = {{Brink, Volker}}, publisher = {{Verlagsschriftenreihe des Heinz Nixdorf Instituts, Paderborn}}, title = {{{Verfahren zur Entwicklung konsistenter Produkt- und Technologiestrategien}}}, volume = {{280}}, year = {{2011}}, }