@inproceedings{39032, abstract = {{Executable UML models are nowadays gaining interest in embedded systems design. This domain is strongly devoted to the modeling of reactive behavior using StateChart variants. In this context, the direct execution of UML state machines is an interesting alternative to native code generation approaches since it significantly increases portability. However, fully featured UML 2.0 State Machines may contain a broad set of features with complex execution semantics that differ significantly from other StateChart variants. This makes their direct execution complex and inefficient. In this paper, we demonstrate how such state machines can be represented using a small subset of the UML state machine features that enables efficient execution. We describe the necessary model transformations in terms of graph transformations and discuss the underlying semantics and implications for execution.}}, author = {{Schattkowsky, Tim and Müller, Wolfgang}}, booktitle = {{Proceedings of VL/HCC 05}}, isbn = {{0-7695-2443-5}}, keywords = {{Unified modeling language, Software design, Virtual machining, Embedded system, Programming, Documentation, Hardware, Computer languages, Operating systems, Runtime}}, title = {{{Transformation of UML State Machines for Direct Execution}}}, doi = {{10.1109/VLHCC.2005.64}}, year = {{2005}}, } @inproceedings{39061, abstract = {{This article presents an approach, which combines theorem proving-based refinement with model checking for state based real-time systems. Our verification flow starts from UML state diagrams, which are translated to the formal B language and are model checked for real-time properties. By means of the B language and a B theorem prover, refined state diagrams are verified against their abstract representation. The approach is presented by means of the refinement of a digital echo cancellation unit.}}, author = {{Krupp, Alexander and Müller, Wolfgang and Oliver, Ian}}, booktitle = {{Proceedings of DATE’04 Designers' Forum}}, isbn = {{0-7695-2085-5}}, keywords = {{Echo cancellers, Logic, Unified modeling language, Automata, Data structures, Boolean functions, Electronic design automation and methodology, Prototypes, Specification languages, Constraint theory}}, title = {{{Formal Refinement and Model Checking of An Echo Cancellation Unit}}}, doi = {{10.1109/DATE.2004.1269214}}, year = {{2004}}, } @inproceedings{39069, abstract = {{We present the syntax and semantics of a past- and future-oriented temporal extension of the Object Constraint Language (OCL). Our extension supports designers to express time-bounded properties over a state-oriented UML model of a system under development. The semantics is formally defined over the system states of a mathematical object model. Additionally, we present a mapping to Clocked Linear Temporal Logic (Clocked LTL) formulae, which is the basis for further application in verification with model checking. We demonstrate the applicability of the approach by the example of a buffer specification in the context of a production system.}}, author = {{Flake, Stephan and Müller, Wolfgang}}, booktitle = {{Proceedings of SEFM´04}}, isbn = {{0-7695-2222-X}}, keywords = {{Unified modeling language, Logic, Clocks, Boolean functions, Application software, Time factors, Real time systems, Formal verification, Buffer storage, Software packages}}, publisher = {{IEEE}}, title = {{{Past- and Future-Oriented Time-Bound Temporal Properties with OCL}}}, doi = {{10.1109/SEFM.2004.1347516}}, year = {{2004}}, } @inproceedings{39403, abstract = {{The Unified Modeling Language (UML) has received wide acceptance as a standard language in the field of software specification by means of different diagram types. In a recent version of UML, the textual Object Constraint Language (OCL) was introduced to support specification of constraints for UML models. But OCL currently does not provide sufficient means to specify constraints over the dynamic behavior of a model. This article presents an OCL extension that is consistent with current OCL and enables modelers to specify state-related time-bounded constraints. We consider the case study of a flexible manufacturing system and identify typical real-time constraints. The constraints are presented in our temporal OCL extension as well as in temporal logic formulae. For general application, we define a semantics of our OCL extension by means of a time-bounded temporal logic based on Computational Tree Logic (CTL).}}, author = {{Flake, Stephan and Müller, Wolfgang}}, booktitle = {{Proceedings of HICSS-35}}, isbn = {{0-7695-1435-9}}, keywords = {{Unified modeling language, Logic, Formal verification, Real time systems, Programming profession, Vehicle dynamics, Software standards, Flexible manufacturing systems, Electronics industry, Protocols}}, location = {{Big Island, HI, USA }}, title = {{{Specification of Real-Time Properties for UML Models}}}, doi = {{10.1109/HICSS.2002.994469}}, year = {{2002}}, } @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}}, } @inproceedings{39411, abstract = {{Rapid prototyping based on 3D models is well accepted for several applications. This article addresses the application of animated virtual 3D prototypes for the development of computer-based systems supporting early collaboration of the system designer with the external customer. Our methodology seamlessly integrates illustration through 3D animation with the main tasks of computer-based real-time systems development, i.e., implementation and verification. The approach is outlined by the example of the design of a flexible manufacturing system.}}, author = {{Flake, Stephan and Geiger, Christian and Müller, Wolfgang and Ruf, Jürgen}}, booktitle = {{Proceedings of IEEE KMN 2001}}, isbn = {{0-7695-1269-0}}, keywords = {{Virtual prototyping, Animation, Collaboration, System analysis and design, Feedback, Application software, Power system modeling, Handicapped aids, Process design, Contracts}}, title = {{{Customer-Oriented Systems Design through Virtual Prototyps}}}, doi = {{10.1109/ENABL.2001.953425}}, year = {{2001}}, } @inproceedings{39421, abstract = {{We present a rigorous but transparent semantics definition of SystemC that covers method, thread, and clocked thread behavior as well as their interaction with the simulation kernel process. The semantics includes watching statements, signal assignment, and wait statements as they are introduced in SystemC V1.O. We present our definition in form of distributed Abstract State Machines (ASMs) rules reflecting the view given in the SystemC User's Manual and the reference implementation. We mainly see our formal semantics as a concise, unambiguous, high-level specification for SystemC-based implementations and for standardization. Additionally, it can be used as a sound basis to investigate SystemC interoperability with Verilog and VHDL.}}, author = {{Müller, Wolfgang and Ruf, Jürgen and Hoffmann, D. W. and Gerlach, Joachim and Kropf, Thomas and Rosenstiehl, W.}}, booktitle = {{Proceedings of the Design, Automation, and Test in Europe (DATE’01)}}, isbn = {{0-7695-0993-2}}, keywords = {{Yarn, Formal verification, Kernel, Hardware design languages, Electronic design automation and methodology, Algebra, Computational modeling, Logic functions, Computer languages, Clocks}}, publisher = {{IEEE}}, title = {{{The Simulation Semantics of SystemC}}}, doi = {{10.1109/DATE.2001.915002}}, year = {{2001}}, } @inproceedings{39487, abstract = {{This article introduces and discusses different innovative means for visual specification and animation of complex concurrent systems. It introduces the completely visual programming language Pictorial Janus (PJ) and its application in the customer-oriented design process. PJ implements a completely visual programming language with inherent animation facilities. The article outlines the transformation of purely visual PJ programs into textual imperative programming languages. The second part of the article investigates animated 3D-presentations and introduces a novel approach to an animated 3D programming language for interactive customer-oriented illustrations.}}, author = {{Geiger, Christian and Lehrenfeld, G. and Müller, Wolfgang}}, booktitle = {{Proceedings of HICSS-32}}, isbn = {{0-7695-0001-3}}, keywords = {{Animation, Computer languages, Object oriented modeling, Collaboration, Process design, Graphical user interfaces, Jacobian matrices, Standardization, Feedback, Software prototyping}}, location = {{Maui, Hawaii}}, title = {{{Visual Specification, Modeling, and Illustrations of Complex Systems}}}, doi = {{10.1109/HICSS.1999.772621}}, year = {{1999}}, } @inproceedings{39505, abstract = {{3D-graphics are becoming popular in a steadily increasing number of areas such as entertainment, scientific visualization, simulation, and virtual reality. Despite this rapid growth the generation of animated 3D scenes is by no means trivial. Since animated 3D objects evolve over time the authors denote these objects as 4D. The article presents a novel approach to the rapid prototyping of 4D models. They introduce the AAL (Animated Agent Layer) system. AAL is an interpreter-based approach covering a textual (AAL-PR) as well as a visual command language (AAL-VL) for the specification of the dynamics in 4D scenes. AAL provides support for different levels of abstraction: primitives, structured objects, animated objects, and animated (autonomous) agents.}}, author = {{Dücker, M. and Geiger, Christian and Hunstock, R. and Lehrenfeld, Georg and Müller, Wolfgang}}, booktitle = {{Proceedings of the 1997 IEEE Symposium on Visual Languages}}, isbn = {{0-8186-8144-6}}, keywords = {{Prototypes, Layout, Animation, Command languages, Application software, Libraries, Virtual reality, Computer graphics, Hardware, Context modeling}}, title = {{{Visual-Textual Prototyping of 4D Scenes}}}, doi = {{10.1109/VL.1997.626601}}, year = {{1997}}, } @inproceedings{39538, abstract = {{This article discusses the application of Pictorial Janus (PJ) for the rapid development and analysis of protocols by animation and complete visualization. In order to make PJ applicable in the context of hardware description we first extend PJ by timing facilities (Timed PJ) and introduce an approach for integrating VHDL models into this visual framework preserving the simulation semantics of VHDL. We finally give the example of the specification and animation of a non interlocked protocol.}}, author = {{Müller, Wolfgang and Lehrenfeld, Georg and Tahedl, C.}}, booktitle = {{Proceedings of ASP-DAC'95/CHDL'95/VLSI'95 with EDA Technofair}}, isbn = {{4-930813-67-0}}, keywords = {{Animation, Protocols, Timing, Computer languages, Electronic mail, Context modeling, Visualization, Control systems, Flow graphs, Trademarks}}, title = {{{Complete Visual Specification and Animations of Protocols}}}, doi = {{10.1109/ASPDAC.1995.486383}}, 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}}, }