@article{34442, abstract = {{Radial shaft seals are used in a variety of applications, where rotating shafts in steady housings have to be sealed. Typical examples are crankshafts, camshafts, differential gear or hydraulic pumps. In the operating state the elastomeric seal ring and the shaft are separated by a lubrication film of just a few micrometers. Due to shear strain and fluid friction the contact area is subject to a higher temperature than the rest of the seal ring. The stiffness of the elastomeric material is intensely influenced by this temperature and thus contact pressure, friction and wear also strongly depend on the contact temperature. In order to simulate the contact behavior of elastomer seal rings it is essential to use a comprehensive approach which takes into consideration the interaction of temperature, friction and wear. Based on this idea a macroscopic simulation model has been developed at the MEGT. It combines a finite element approach for the simulation of contact pressure at different wear states, a semi-analytical approach for the calculation of contact temperature and an empirical approach for the calculation of friction. In this paper the model setup is presented, as well as simulation and experimental results.}}, author = {{Frölich, D. and Magyar, Balázs and Sauer, B.}}, issn = {{0043-1648}}, journal = {{Wear}}, keywords = {{Radial shaft seal ring, Contact temperature, Wear, Friction torque, Finite element simulation}}, number = {{1}}, pages = {{71--80}}, title = {{{A comprehensive model of wear, friction and contact temperature in radial shaft seals}}}, doi = {{https://doi.org/10.1016/j.wear.2013.12.030}}, volume = {{311}}, year = {{2014}}, } @inproceedings{9784, abstract = {{Piezoelectric inertia motors use the inertia of a body to drive it by means of a friction contact in a series of small steps. These motors can operate in ``stick-slip'' or ``slip-slip'' mode, with the fundamental frequency of the driving signal ranging from several Hertz to more than 100 kHz. To predict the motor characteristics, a Coulomb friction model is sufficient in many cases, but numerical simulation requires microscopic time steps. This contribution proposes a much faster simulation technique using one evaluation per period of the excitation signal. The proposed technique produces results very close to those of timestep simulation for ultrasonics inertia motors and allows direct determination of the steady-state velocity of an inertia motor from the motion profile of the driving part. Thus it is a useful simulation technique which can be applied in both analysis and design of inertia motors, especially for parameter studies and optimisation.}}, author = {{Hunstig, Matthias and Hemsel, Tobias and Sextro, Walter}}, booktitle = {{Ultrasonics Symposium (IUS), 2012 IEEE International}}, issn = {{1948-5719}}, keywords = {{friction, ultrasonic motors, Coulomb friction model, efficient simulation technique, friction contact, high-frequency piezoelectric inertia motor, motor characteristics prediction, numerical simulation, slip-slip mode, stick-slip mode, time-step simulation, ultrasonic inertia motor, Acceleration, Acoustics, Actuators, Computational modeling, Friction, Numerical models, Steady-state}}, pages = {{277--280}}, title = {{{An efficient simulation technique for high-frequency piezoelectric inertia motors}}}, doi = {{10.1109/ULTSYM.2012.0068}}, year = {{2012}}, } @article{45933, author = {{Karátson, J. and Kovács, Balázs}}, issn = {{0898-1221}}, journal = {{Computers & Mathematics with Applications}}, keywords = {{Computational Mathematics, Computational Theory and Mathematics, Modeling and Simulation}}, number = {{3}}, pages = {{449--459}}, publisher = {{Elsevier BV}}, title = {{{Variable preconditioning in complex Hilbert space and its application to the nonlinear Schrödinger equation}}}, doi = {{10.1016/j.camwa.2012.04.021}}, volume = {{65}}, year = {{2012}}, } @inproceedings{23858, abstract = {{A large proportion of plastics today is compounded, which means the process from refining a raw material to the processable material. For this process compounding extruders are used which mostly involve tightly intermeshing, co-rotating twin screw extruders. These extruders consist of two closely spaced screws which rotate in the same direction and convey the raw material to the screw tip. These screws are surrounded by several barrel modules which heat or cool the material. As the whole design of the machine is modularly arranged the process behavior of a twin screw extruder depends for the main part on the arrangement of the screw and the barrel elements. Until today this arrangement and process optimization is conducted by experienced engineers and with the help of trial-and-error methods. Furthermore, theoretical models are used with which the behavior of the extruder is estimated. As these models are mostly very complex they are only made available with the realization in different software projects. One of the tools is called SIGMA. Within this paper SIGMA is introduced as a software to optimize a twin screw extruder. SIGMA supports the engineer already in the early stages of the extruder arrangement.}}, author = {{Kretzschmar, Nils and Schöppner, Volker}}, booktitle = {{Proceedings of the 2010 Summer Computer Simulation Conference}}, keywords = {{process optimization, polymer engineering, compounding, twin screw extruder, simulation}}, pages = {{133–140}}, publisher = {{Society for Computer Simulation International}}, title = {{{Simulating Tightly Intermeshing, Co-Rotating Twin Screw Extruders with SIGMA}}}, year = {{2010}}, } @article{3693, abstract = {{Erbschaftsteuer | Inheritance tax | Steuerreform | Tax reform | Steuerwirkung | Tax effects | Steuereinnahmen | Tax revenue | Mikrodaten | Microdata | Simulation | Deutschland | Germany}}, author = {{Maiterth, Ralf and Houben, Henriette and Broekelschen, Wiebke and Müller, Jens and Sureth-Sloane, Caren}}, journal = {{Statistik und Wissenschaft}}, keywords = {{Erbschaftsteuer | Inheritance tax | Steuerreform | Tax reform | Steuerwirkung | Tax effects | Steuereinnahmen | Tax revenue | Mikrodaten | Microdata | Simulation}}, pages = {{163----183}}, title = {{{Mikroanalytische Begleitung der Steuerpolitik am Beispiel der Erbschaftsteuerreform}}}, year = {{2009}}, } @inbook{33813, abstract = {{Today, mobile and embedded real-time systems have to cope with the migration and allocation of multiple software tasks running on top of a real-time operating system (RTOS) residing on one or several system processors. Each RTOS has to be configured towards the individual needs of the application and environment. For this, different scheduling strategies and task priorities have to be evaluated in order to keep execution and response times for a given task set. Abstract RTOS simulation is applied to analyze different parameters in early design phases. This chapter presents a SystemC RTOS library for abstract yet accurate RTOS sim- ulation, supporting modeling of preemption in the presence of prioritized and nested interrupts. After introducing basic principles of abstract RTOS simula- tion, we present our SystemC library in detail. Thereafter, we discuss related approaches and close with applications in electronic automotive systems design and some evaluations.}}, author = {{Zabel, Henning and Müller, Wolfgang and Gerstlauer, Andreas}}, booktitle = {{Hardware Dependent Software - Principles and Practice}}, editor = {{Ecker, Wolfgang and Müller, Wolfgang and Dömer, Rainer}}, isbn = {{978-1-4020-9435-4}}, keywords = {{RTOS Modelling, RTOS Simulation, SystemC, Task Scheduling, Interrupt Analysis}}, pages = {{233--260}}, publisher = {{Springer Verlag}}, title = {{{Accurate RTOS Modelling and Analysis with SystemC}}}, doi = {{10.1007/978-1-4020-9436-1_9}}, year = {{2009}}, } @inproceedings{17272, abstract = {{In developmental research, tutoring behavior has been identified as scaffolding infants' learning processes. It has been defined in terms of child-directed speech (Motherese), child-directed motion (Motionese), and contingency. In the field of developmental robotics, research often assumes that in human-robot interaction (HRI), robots are treated similar to infants, because their immature cognitive capabilities benefit from this behavior. However, according to our knowledge, it has barely been studied whether this is true and how exactly humans alter their behavior towards a robotic interaction partner. In this paper, we present results concerning the acceptance of a robotic agent in a social learning scenario obtained via comparison to adults and 8-11 months old infants in equal conditions. These results constitute an important empirical basis for making use of tutoring behavior in social robotics. In our study, we performed a detailed multimodal analysis of HRI in a tutoring situation using the example of a robot simulation equipped with a bottom-up saliency-based attention model. Our results reveal significant differences in hand movement velocity, motion pauses, range of motion, and eye gaze suggesting that for example adults decrease their hand movement velocity in an Adult-Child Interaction (ACI), opposed to an Adult-Adult Interaction (AAI) and this decrease is even higher in the Adult-Robot Interaction (ARI). We also found important differences between ACI and ARI in how the behavior is modified over time as the interaction unfolds. These findings indicate the necessity of integrating top-down feedback structures into a bottom-up system for robots to be fully accepted as interaction partners.}}, author = {{Vollmer, Anna-Lisa and Lohan, Katrin Solveig and Fischer, Kerstin and Nagai, Yukie and Pitsch, Karola and Fritsch, Jannik and Rohlfing, Katharina and Wrede, Britta}}, booktitle = {{Development and Learning, 2009. ICDL 2009. IEEE 8th International Conference on Development and Learning}}, keywords = {{robot simulation, hand movement velocity, robotic interaction partner, robotic agent, robot-directed interaction, multimodal analysis, Motionese, Motherese, intelligent tutoring systems, immature cognitive capability, human computer interaction, eye gaze, child-directed speech, child-directed motion, bottom-up system, bottom-up saliency-based attention model, adult-robot interaction, adult-child interaction, adult-adult interaction, human-robot interaction, action learning, social learning scenario, social robotics, software agents, top-down feedback structures, tutoring behavior}}, pages = {{1--6}}, publisher = {{IEEE}}, title = {{{People modify their tutoring behavior in robot-directed interaction for action learning}}}, doi = {{10.1109/DEVLRN.2009.5175516}}, year = {{2009}}, } @inproceedings{37075, abstract = {{Complex control oriented embedded systems with hard real-time constraints require real-time operation system (RTOS) for predictable timing behavior. To support the evaluation of different scheduling strategies and task priorities, we use an abstract RTOS model based on SystemC. In this article, we present an annotation method for time estimation that supports flexible simulation and validation of real-time-constraints for task migration between different target processors without loss of simulation performance and less memory overhead.}}, author = {{Zabel, Henning and Müller, Wolfgang}}, editor = {{Kleinjohann, L. and Kleinjohann, B.}}, isbn = {{978-0-387-09660-5}}, keywords = {{Execution Time Schedule Strategy Simulation Speed Task Migration Atomic Block}}, publisher = {{Springer Verlag}}, title = {{{An Efficient Time Annotation Technique in Abstract RTOS Simulations for Multiprocessor Task Migration}}}, doi = {{10.1007/978-0-387-09661-2_18}}, volume = {{271}}, year = {{2008}}, } @article{2412, abstract = {{ Reconfigurable architectures that tightly integrate a standard CPU core with a field-programmable hardware structure have recently been receiving impact of these design decisions on the overall system performance is a challenging task. In this paper, we first present a framework for the cycle-accurate performance evaluation of hybrid reconfigurable processors on the system level. Then, we discuss a reconfigurable processor for data-streaming applications, which attaches a coarse-grained reconfigurable unit to the coprocessor interface of a standard embedded CPU core. By means of a case study we evaluate the system-level impact of certain design features for the reconfigurable unit, such as multiple contexts, register replication, and hardware context scheduling. The results illustrate that a system-level evaluation framework is of paramount importance for studying the architectural trade-offs and optimizing design parameters for reconfigurable processors.}}, author = {{Enzler, Rolf and Plessl, Christian and Platzner, Marco}}, journal = {{Microprocessors and Microsystems}}, keywords = {{FPGA, reconfigurable computing, co-simulation, Zippy}}, number = {{2-3}}, pages = {{63--73}}, publisher = {{Elsevier}}, title = {{{System-level performance evaluation of reconfigurable processors}}}, doi = {{10.1016/j.micpro.2004.06.004}}, volume = {{29}}, year = {{2005}}, } @inproceedings{2422, abstract = {{Reconfigurable computing architectures aim to dynamically adapt their hardware to the application at hand. As research shows, the time it takes to reconfigure the hardware forms an overhead that can significantly impair the benefits of hardware customization. Multi-context devices are one promising approach to overcome the limitations posed by long reconfiguration times. In contrast to more traditional reconfigurable architectures, multi-context devices hold several configurations on-chip. On demand, the device can quickly switch to another context. In this paper we present a co-simulation environment to investigate design trade-offs for hybrid multi-context architectures. Our architectural model comprises a reconfigurable unit closely coupled to a CPU core. As a case study, we discuss the implementation of a FIR filter partitioned into several contexts. We outline the mapping process and present simulation results for single- and multi-context reconfigurable units coupled with both embedded and high-end CPUs.}}, author = {{Enzler, Rolf and Plessl, Christian and Platzner, Marco}}, booktitle = {{Proc. Int. Conf. on Engineering of Reconfigurable Systems and Algorithms (ERSA)}}, isbn = {{1-932415-05-X}}, keywords = {{Zippy, co-simulation}}, pages = {{174--180}}, publisher = {{CSREA Press}}, title = {{{Co-simulation of a Hybrid Multi-Context Architecture}}}, year = {{2003}}, } @article{45418, author = {{Mahnken, Rolf and Tikhomirov, D. and Stein, E.}}, issn = {{0045-7949}}, journal = {{Computers & Structures}}, keywords = {{Computer Science Applications, Mechanical Engineering, General Materials Science, Modeling and Simulation, Civil and Structural Engineering}}, number = {{2}}, pages = {{135--143}}, publisher = {{Elsevier BV}}, title = {{{Implicit integration scheme and its consistent linearization for an elastoplastic-damage model with application to concrete}}}, doi = {{10.1016/s0045-7949(99)00089-9}}, volume = {{75}}, year = {{2002}}, } @article{45423, author = {{Mahnken, Rolf}}, issn = {{1069-8299}}, journal = {{Communications in Numerical Methods in Engineering}}, keywords = {{Applied Mathematics, Computational Theory and Mathematics, General Engineering, Modeling and Simulation, Software}}, number = {{10}}, pages = {{745--754}}, publisher = {{Wiley}}, title = {{{Improved implementation of an algorithm for non-linear isotropic/kinematic hardening in elastoplasticity}}}, doi = {{10.1002/(sici)1099-0887(199910)15:10<745::aid-cnm288>3.0.co;2-r}}, volume = {{15}}, year = {{2002}}, } @article{45422, author = {{Mahnken, Rolf}}, issn = {{0045-7949}}, journal = {{Computers & Structures}}, keywords = {{Computer Science Applications, Mechanical Engineering, General Materials Science, Modeling and Simulation, Civil and Structural Engineering}}, number = {{2}}, pages = {{179--200}}, publisher = {{Elsevier BV}}, title = {{{A comprehensive study of a multiplicative elastoplasticity model coupled to damage including parameter identification}}}, doi = {{10.1016/s0045-7949(98)00296-x}}, volume = {{74}}, year = {{2002}}, } @article{45432, author = {{Mahnken, Rolf and Stein, E}}, issn = {{0965-0393}}, journal = {{Modelling and Simulation in Materials Science and Engineering}}, keywords = {{Computer Science Applications, Mechanics of Materials, Condensed Matter Physics, General Materials Science, Modeling and Simulation}}, number = {{3A}}, pages = {{597--616}}, publisher = {{IOP Publishing}}, title = {{{The identification of parameters for visco-plastic models via finite-element methods and gradient methods}}}, doi = {{10.1088/0965-0393/2/3a/013}}, volume = {{2}}, year = {{2002}}, } @inbook{34448, abstract = {{We present a rigorous but transparent semantic definition for VHDL corresponding to the IEEE VHDL’ 93 standard [68, 9, 84]. Our definition covers the full behavior of signal and variable assignments as well as the behavior of the various wait statements including delta, time, and postponed cycles. We consider explicitly declared signals, ports, local variables, and shared variables. Our specification defines an abstract VHDL ’ 93 interpreter in the form of transition rules for an evolving algebra machine (EA-Machine) [60]. It faithfully reflects and supports the view of simulation given in the IEEE VHDL ’ 93 standard language reference manual. The definition can be understood without any prior formal training. We illustrate our definition by running the example VHDL program set out in the Introduction to this volume.}}, author = {{Börger, Egon and Glässer, Uwe and Müller, Wolfgang}}, booktitle = {{Semantics of VHDL}}, editor = {{Delgado Kloos, C. and Breuer, Peter T.}}, isbn = {{978-1-4615-2237-9}}, keywords = {{Transition Rule Formal Verification Variable Assignment Kernel Process Simulation Cycle}}, pages = {{107 -- 139}}, publisher = {{Kluwer Academic Publishers}}, title = {{{A Formal Definition of an Abstract VHDL'93 Simulator by EA-Machines}}}, doi = {{10.1007/978-1-4615-2237-9_5}}, year = {{1995}}, } @article{40218, author = {{Lasser, R. and Rösler, Margit}}, issn = {{0304-4149}}, journal = {{Stochastic Processes and their Applications}}, keywords = {{Applied Mathematics, Modeling and Simulation, Statistics and Probability}}, number = {{2}}, pages = {{279--293}}, publisher = {{Elsevier BV}}, title = {{{Linear mean estimation of weakly stationary stochastic processes under the aspects of optimality and asymptotic optimality}}}, doi = {{10.1016/0304-4149(91)90095-t}}, volume = {{38}}, year = {{1991}}, }