@inproceedings{39363, abstract = {{The textual Object Constraint Language (OCL) is an of- ficial part of the Unified Modeling Language (UML). It is primarily used to formulate restrictions for UML class di- agrams. Additionally, it is possible to refer to UML State- chart states in OCL expressions to reason about currently activated states. However, neither the current OCL standard nor the pro- posal for the new OCL 2.0 version integrate Statecharts on the language definition level, i.e., the semantics of State- chart states in the context of OCL expressions is not suf- ficiently defined so far. To overcome this deficiency, this article provides a formal semantics for state-oriented OCL expressions for application with UML Statecharts.}}, author = {{Flake, Stephan and Müller, Wolfgang}}, booktitle = {{Proceedings of SEKE 2003}}, title = {{{Semantics of State-Oriented Expressions in the Object Constraint Language}}}, year = {{2003}}, } @inproceedings{39367, abstract = {{Confidentiality and security in data access and transmission over multiple open networks are of utmost importance for most collaborative engineering environments. In this article, we review smart card based security technologies for their application in computer-based collaborative engineering environments. We focus on most recent microprocessor-based smart cards and on JavaCard as a development infrastructure and operating system. Since JavaCard supports the integration of multiple applications on one card, it enables smart cards to integrate large sets of additional applications. In that context, we identify and discuss three potential key applications: authentication with biometrics, certification, and advanced profile management.}}, author = {{Wang, J. and Müller, Wolfgang}}, booktitle = {{Proceedings of CCE'03}}, title = {{{SmartCard for Secure Collaborative Engineering}}}, year = {{2003}}, } @inproceedings{39360, author = {{Krupp, Alexander and Müller, Wolfgang}}, title = {{{Formale Verfeinerung und Modelchecking von zeitbehafteten endlichen Automaten}}}, year = {{2003}}, } @inproceedings{39368, author = {{Krupp, Alexander and Müller, Wolfgang}}, booktitle = {{Proceedings of FDL'03}}, title = {{{Combining Formal Refinement and Model Checking for Analysis of Realtime Systems}}}, year = {{2003}}, } @inproceedings{39369, abstract = {{The latest OCL 2.0 proposal provides two semantic descriptions, i.e., a metamodel based semantics that uses UML itself to associate the semantic domain with the language concepts and a formal semantics based on a set-theoretic approach called object model. Unfortunately, these two semantics are currently neither consistent nor complete, as (a) the formal semantics does not consider the newly introduced concept of OCL messages and (b) both semantics lack an integration of Statecharts and a semantic denition of state-related operations. This article focuses on a formal semantics for OCL messages as a foundation for consistency among,the two OCL semantics. We extend object models and present an extended denition of a system state that comprises all relevant information to be able to evaluate OCL expressions also w.r.t. OCL messages.}}, author = {{Flake, Stephan and Müller, Wolfgang}}, booktitle = {{Proceedings of the Workshop OCL 2.0 at UML 2003}}, title = {{{Formal Semantics of OCL Messages}}}, year = {{2003}}, } @inbook{34447, abstract = {{The Object Constraint Language (OCL) was introduced to support the specification of constraints for UML diagrams and is mainly used to formulate invariants and operation pre- and postconditions. Though OCL is also applied in behavioral diagrams, e.g., as guards for state transitions, it is currently not possible to specify constraints concerning the dynamic behavior and timing properties of such diagrams. This article discusses OCL’s application for the dynamic behavior of UML Statechart diagrams and presents an OCL extension for specification of state-oriented time-bounded constraints.We introduce operations to extract state configurations from diagrams and define additional predicates over states and state configurations. The semantics of our OCL extension is given by employing time-bounded Computational Tree Logic (CTL) formulae. An example of a flexible manufacturing system with automated guided vehicles demonstrates the application of our extension.}}, author = {{Flake, Stephan and Müller, Wolfgang}}, booktitle = {{Advances in Object Modelling with the OCL}}, editor = {{Clark, T. and Warmer, J.}}, isbn = {{978-3-540-45669-8}}, keywords = {{Model Check Temporal Logic Object Constraint Language Execution Path Kripke Structure}}, pages = {{150 -- 171}}, publisher = {{Springer-Verlag}}, title = {{{An OCL Extension for Real-Time Constraints}}}, doi = {{10.1007/3-540-45669-4_8}}, year = {{2002}}, } @article{34576, author = {{Eikerling, H. J. and Müller, Wolfgang and Wegener, J.}}, journal = {{it+ti}}, pages = {{128--136}}, publisher = {{Oldenbourg Verlag}}, title = {{{Werkzeugintegration und -verwaltung in heterogenen Computernetzwerken}}}, year = {{2002}}, } @book{53586, editor = {{Bücker, Ulrich and Eikerling, Heinz Josef and Müller, Wolfgang}}, isbn = {{3-826598-84-9}}, title = {{{Proceedings of the VHE Workshop}}}, year = {{2002}}, } @inproceedings{39371, abstract = {{With the increasing availability of various web-enabled mobile devices, content has to be effectively adapted to their different limitations. So, web content need rearrangement, i.e., a transcoding, to better fit on small displays when, for instance, layout specific HTML structures like tables and frames are used. In this article, we present a description language to define generic rules for this purpose and introduce RDL/TT (Rule Description Language for Tree Transformation). RDL/TT specifies sets of transcoding functions generic to user and hardware profiles. A Java-oriented syntax is used to describe the transcoding functions which operate on the DOM (Document Object Model) tree representation of an HTML or XML document.}}, author = {{Schäfer, Robbie and Dangberg, Andreas and Müller, Wolfgang}}, booktitle = {{Proceedings of the VHE Workshop}}, title = {{{RDL/TT - A Description Language for Profile-Dependent Transcoding of XML Documents}}}, year = {{2002}}, } @inproceedings{39370, abstract = {{Within this paper we propose architecture ideas of a distributed Video on Demand network which base on peer to peer technology. Each peer offers video streams to other peers and may receive a video stream from another peer simultaneously. This results in an optimization problem depending on different factors which we approximate with the help of an simulation environment. Our approach bases on a peer to peer framework by Sun called Project JXTA which provides a set of protocols for P2P applications.}}, author = {{Loeser, Chris and Altenbernd, Peter and Ditze, Michael and Müller, Wolfgang}}, booktitle = {{Proceedings of the Intl. Workshop on Real-Time LANs in the Internet Age (RTLIA 2002)}}, title = {{{Distributed Video-on-Demand Services on Peer to Peer Basis}}}, year = {{2002}}, } @inproceedings{39378, author = {{Schäfer, Robbie and Müller, Wolfgang and Dangberg, Andreas}}, booktitle = {{Proceedings of the HICSS-35}}, title = {{{Fuzzy Rules for the Transcoding of HTML Files}}}, year = {{2002}}, } @inproceedings{39398, abstract = {{This article presents a UML profile for an OCL extension that enables modelers to specify behavioral, state-oriented real-time constraints in OCL. In order to perform a seamless integration into the upcoming UML2.0 standard, we take the latest OCL2.0 metamodel proposal by Warmer et al. [22] as a basis. A formal semantics of our temporal OCL extension is given by a mapping to time-annotated temporal logics formulae. To give an example of the applicability of our extension, we consider a modeling approach for manufacturing systems called MFERT. We present a corresponding UML profile for that approach and combine both profiles for formal verification by real-time model checking.}}, author = {{Flake, Stephan and Müller, Wolfgang}}, booktitle = {{Proceedings of the UML 2002 - The Unified Modeling Language}}, publisher = {{Springer-Verlag}}, title = {{{A UML Profile for Real-Time Constraints with the OCL}}}, year = {{2002}}, } @inproceedings{39393, author = {{Dangelmeier, Wilhelm and Darnedde, C. and Flake, Stephan and Müller, Wolfgang and Pape, U.}}, title = {{{Graphische Spezifikation und Echtzeitverifikation von Produktionsautomatisierungssystemen}}}, year = {{2002}}, } @inproceedings{39382, abstract = {{We present a rigorous but transparent semantics definition of the SpecC language that covers the execution of SpecC behaviors and their interaction with the kernel process. The semantics include wait, wait for, par, and try statements as they are introduced in SpecC. We present our definition in form of distributed abstract state machine (ASM) rules strictly following the lines of the SpecC Language Reference Manual. We mainly see our formal semantics in three application areas. First, it is a concise, unambiguous description for documentation and standardization. Second, it applies as a high-level, pseudo code-oriented specification for the implementation of a SpecC simulator. Finally, it is a first step for SpecC synthesis in order to identify similar concepts with other languages like VHDL and SystemC for the definition of common patterns and language subsets.}}, author = {{Müller, Wolfgang and Dömer, Rainer and Gerstlauer, Andreas}}, booktitle = {{Proceedings of the ISSS02}}, isbn = {{1-58113-576-9}}, keywords = {{Standardization, Kernel, Permission, Formal verification, Logic functions, Documentation, Reasoning about programs, Specification languages, Formal specifications, Software systems}}, title = {{{The Formal Execution Semantics of SpecC}}}, doi = {{10.1145/581199.581234 }}, year = {{2002}}, } @inproceedings{39387, abstract = {{This paper compares the use of three different approaches to transcoding of XML [Extensible Markup Language]-based user interface descriptions to other target formats. The source is the interface section of the XML-based markup language for user interfaces, UIML [User Interface Markup Language], which has been extended with a vocabulary for the description of generic user interfaces. Target formats used as examples for the comparison are HTML [Hypertext Markup Language], and VoiceXML. The compared means for transcoding are XSLT [Extensible Stylesheet Language Transformation], the UIML peers section with enhancements for transcoding, and RDL/TT [Rule Description Language for Tree Transformation], a Java-like transcoding language. Rendered by www.RenderX.com Comparing Transcoding Tools for Use with a Generic User Interface Format.}}, author = {{Plomp, Johan and Schäfer, Robbie and Müller, Wolfgang}}, booktitle = {{Proceedings of the Extreme Markup Languages 2002}}, title = {{{Comparing Transcoding Tools for Use with a Generic User Interface Format}}}, year = {{2002}}, } @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}}, } @inproceedings{39402, abstract = {{Die Object Constraint Language (OCL) wurde entwickelt, um Modelleinschränkungen beim objektorientierten Softwareentwurf mit der UML [14] ausdrücken zu können. Sie wird hauptsächlich benutzt, um Invarianten für Objekte sowie Vor-und Nachbedingungen von Operationen zu spezifizieren. Zurzeit bieten OCL und Echtzeiterweiterungen der UML nur bedingt geeignete Mittel, um temporale zeitbehaftete Modelleigenschaften zu beschreiben. Insbesondere kann man mit OCL keine Einschränkunge uber das dynamische Verhalten eines UML-Modells formulieren, die die Reihenfolge von Objektzuständen und Zustandsübergängen betreffen. Um ein korrektes Systemverhalten zu garantieren, ist es jedoch insbesondere bei zeitkritischen Anwendungen notwendig, solche zustandsbasierten zeitbehafteten Einschränkungen in einer formalen Art und Weise ausdrücken zu können. Es sind daher verschiedene Vorschläge veröffentlicht worden, in denen die OCL erweitert worden ist, um Modellierern die Möglichkeit zu geben, temporale Einschränkungen zu formulieren. Dieser Artikel gibt eine Überblick über die zurzeit bekannten Vorschläge und zeigt Ansätze für weitere Entwicklungen in diesem Bereich auf.}}, author = {{Flake, Stephan and Müller, Wolfgang}}, title = {{{Temporale Erweiterungen der OCL - Überblick und Aussichten}}}, 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{39407, abstract = {{This article presents challenges, visions, and solutions for a true Pan- European collaborative engineering infrastructure that is a target of the IST project E-COLLEG. The consortium aims at the definition of a transparent infrastructure that will enable engineers from various domains to collaborate during the design of complex heterogeneous systems. In this context, we introduce an advanced collaborative infrastructure (ACI). ACI covers dynamic Tool Registration and Management Services (TRMS) for distance-spanning, tool integration and administration, as well as open interfaces for XML-based data exchange. TRMS will constitute a backbone for E-COLLEG-related pan-European collaborative research and engineering studies by fostering a combination of most recent Plug- and-Play techniques employing agent-based communication based on XML- oriented integration technologies. This new enabling technology for collaborative engineering is validated in two application scenarios.}}, author = {{Bauer, M. and Eikerling, Heinz-Josef and Müller, Wolfgang and Pawlak, A. and Siekierska, K. and Soderberg, D. and Warzee, X.}}, title = {{{Advanced Infrastructure for PAN-European Collaborative Engineering}}}, 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}}, }