检索结果-内蒙古大学图书馆

Journal of Knowledge Management 2005年第5期9卷 97-107页

作者： Haase, Peter Völker, Johanna Sure, York Knowledge Management Group Institute of Applied Computer Science and Formal Description Methods University of Karlsruhe 76128 Karlsruhe Germany Institute of AIFB University of Karlsruhe 76128 Karlsruhe Germany Institute of Applied Computer Sciences and Formal Description Methods University of Karlsruhe 76128 Karlsruhe Germany

Purpose - This paper presents a framework for ontology evolution tailored to Digital Libraries, which makes use of two different sources for change detection and propagation, the usage of ontologies by users and the changes of available data. Design/methodology/approach - After presenting the logical architecture of the evolution framework, we first illustrate how to deal with usage-driven changes, that is changes derived from the actual usage of ontologies. Second, we describe the generation of data-driven ontology changes based on the constant flow of documents coming into digital libraries. Findings - The proposed framework for ontology ontology evolution, which is currently applied and evaluated in the case studies, significantly reduces the costs of ontology updates and improves the quality of the ontology with respect to the user's requirements. Practical implications - The management of dynamic knowledge is crucial for many knowledge management applications. Our approach for usage-driven and data-driven change discovery not only assures the consistency of ontologies modeling dynamic knowledge, but also reduces the burden of manual ontology engineering. Originality/value - This paper presents the first approach towards a common framework for ontology evolution based on usage-driven and data-driven change discovery. © Emerald Group Publishing Limited.

关键词： Data handling Digital libraries Information retrieval Knowledge management

来源：评论

学校读者我要写书评

暂无评论

Complexity results for checking distributed implementability

Complexity results for checking distributed implementability

引用

International Conference on Application of Concurrency to System Design

作者： K. Heljanko A. Stefanescu Laboratory for Theoretical Computer Science Helsinki University of Technology Finland Institute for Formal Methods in Computer Science University of Stuttgart Stuttgart Germany

We consider the distributed implementability problem: Given a labeled transition system TS together with a distribution /spl Delta/ of its actions over a set of processes, does there exist a distributed system over /spl Delta/ such that its global transition system is 'equivalent' to TS? We work with the distributed system models of synchronous products of transition systems (Arnold, 1994) and asynchronous automata (Zielonka, 1987). In this paper we provide complexity bounds for the above problem with three interpretations of 'equivalent': as transition system isomorphism, as language equivalence, and as bisimilarity. In particular, we solve problems left open in Castellani et al. (1999) and Morin (1999).

关键词： Automata computer science Computational complexity Petri nets Laboratories Upper bound Testing Polynomials Hardware Concurrent computing

来源：评论

学校读者我要写书评

暂无评论

A graph based tool for modelling planning processes in building engineering

A graph based tool for modelling planning processes in build...

引用

2005 ASCE International Conference on Computing in Civil Engineering

作者： Klinger, A. König, M. Berkhahn, V. University of Hannover Institute of Computer Science Civil Engineering Callinstraße 34 30167 Hannover Germany Bauhaus University Weimar Theoretical Methods for Project Management Marienstraße 7 99423 Weimar

ISBN: (纸本)0784407940

The planning process of a building is very complex. Many participants with different technical disciplines are involved and work on certain tasks. To manage the planning process the project leader has to organize participants, tasks and building data. For this purpose modern information and communication technologies can be used very efficiently. But these technologies require a formal description of the planning process. Within the research project "Relation Based Process Modelling of Co-operative Building Planning" we have defined a consistent mathematical process model for planning processes and have developed a prototype implementation of an application for modelling these processes. Our project is embedded in the priority program 1103 "Network-based Co-operative Planning Processes in Structural Engineering" promoted by the German Research Foundation (DFG). In this paper we present the mathematical concept of our relational process model and the tool for building up the model and checking the structural consistency and correctness.

关键词： Structural design

来源：评论

学校读者我要写书评

暂无评论

Reachability analysis of synchronized PA systems

Reachability analysis of synchronized PA systems

引用

Proceedings of the 6th International Workshop on Verification of Infinite-State Systems (INFINITY 2004)

作者： Bouajjani, Ahmed Esparza, Javier Touili, Tayssir Liafa University of Paris 7 2 place Jussieu 75251 Paris Cedex 5 France Institute for Formal Methods in Computer Science University of Stuttgart Universitätstr. 38 70569 Stuttgart Germany

We present a generic approach for the analysis of concurrent programs with (unbounded) dynamic creation of threads and recursive procedure calls. We define a model for such programs based on a set of term rewrite rules where terms represent control configurations. The reachability problem for this model is undecidable. Therefore, we propose a method for analyzing such models based on computing abstractions of their sets of computation paths. Our approach allows to compute such abstractions as least solutions of a system of (path language) constraints. More precisely, given a program and two regular sets of configurations (process terms) T and T′, we provide (1) a construction of a system of constraints which characterizes the set of computation paths leading from T to T′, and (2) a generic framework, based on abstract interpretation, allowing to solve this system in various abstract domains leading to abstract analysis with different precision and cost. © 2005 Elsevier B.V. All rights reserved.

关键词： Synchronization

来源：评论

学校读者我要写书评

暂无评论

Analysis and prediction of the long-run behavior of probabilistic sequential programs with recursion

Analysis and prediction of the long-run behavior of probabil...

引用

Annual IEEE Symposium on Foundations of computer science

作者： T. Brazdil J. Esparza A. Kucera Faculty of Informatics Masaryk University Bmo Czech Republic Institute for Formal Methods in Computer Science University of Stuttgart Germany

We introduce a family of long-run average properties of Markov chains that are useful for purposes of performance and reliability analysis, and show that these properties can effectively be checked for a subclass of infinite-state Markov chains generated by probabilistic programs with recursive procedures. We also show how to predict these properties by analyzing finite prefixes of runs, and present an efficient prediction algorithm for the mentioned subclass of Markov chains.

关键词： Logic Automata Personal digital assistants computer science Algorithm design and analysis Informatics Performance analysis Prediction algorithms Failure analysis computer errors

来源：评论

学校读者我要写书评

暂无评论

Quantitative analysis of probabilistic pushdown automata: expectations and variances

Quantitative analysis of probabilistic pushdown automata: ex...

引用

Annual Symposium on Logic in computer science

作者： J. Esparza A. Kucera R. Mayr Institute for Formal Methods in Computer Science University of Stuttgart Stuttgart Germany Faculty of Informatics Masaryk University Brno Czech Republic Department of Computer Science North Carolina State University Raleigh NC USA

Probabilistic pushdown automata (pPDA) have been identified as a natural model for probabilistic programs with recursive procedure calls. Previous works considered the decidability and complexity of the model-checking problem for pPDA and various probabilistic temporal logics. In this paper we concentrate on computing the expected values and variances of various random variables defined over runs of a given probabilistic pushdown automaton. In particular, we show how to compute the expected accumulated reward and the expected gain for certain classes of reward functions. Using these results, we show how to analyze various quantitative properties of pPDA that are not expressible in conventional probabilistic temporal logics.

关键词： Analysis of variance Automata computer science Probabilistic logic Random variables Informatics Probability distribution Performance analysis H infinity control

来源：评论

学校读者我要写书评

暂无评论

Hopping models of charge transfer in a complex environment: Coupled memory continuous-time random walk approach

引用

Physical Review E 2005年第6期72卷 061101-061101页

作者： Ewa Gudowska-Nowak Kinga Bochenek Agnieszka Jurlewicz Karina Weron Marian Smoluchowski Institute of Physics Jagellonian University ul. Reymonta 4 30-059 Kraków Poland Hugo Steinhaus Center for Stochastic Methods and Institute of Mathematics and Computer Science Wrocław University of Technology ul. Wybrzeże Wyspiańskiego 27 50-370 Wrocław Poland Institute of Physics Wrocław University of Technology ul. Wybrzeże Wyspiańskiego 27 50-370 Wrocław Poland

Charge transport processes in disordered complex media are accompanied by anomalously slow relaxation for which usually a broad distribution of relaxation times is adopted. To account for those properties of the environment, a standard kinetic approach in description of the system is addressed either in the framework of continuous-time random walks (CTRWs) or fractional diffusion. In this paper the power of the CTRW approach is illustrated by use of the probabilistic formalism and limit theorems that allow one to rigorously predict the limiting distributions of the paths traversed by charges and to derive effective relaxation properties of the entire system of interest. In particular, the standard CTRW scenario is generalized to a new class of coupled memory CTRWs that effectivly can lead to the well known Havriliak-Negami response. Application of the method is discussed for nonexponential electron-transfer processes controlled by dynamics of the surrounding medium.

关键词： Charge transfer

来源：评论

学校读者我要写书评

暂无评论

Verifying probabilistic procedural programs

Lecture Notes in Computer Science (including subseries Lectu...

引用

Lecture Notes in computer science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) 2004年 3328卷 16-31页

作者： Esparza, Javier Etessami, Kousha Institute for Formal Methods in Computer Science University of Stuttgart Germany School of Informatics University of Edinburgh United Kingdom

Monolithic finite-state probabilistic programs have been abstractly modeled by finite Markov chains, and the algorithmic verification problems for them have been investigated very extensively. In this paper we survey recent work conducted by the authors together with colleagues on the algorithmic verification of probabilistic procedural programs ([BKS, EKM04, EY04]). Probabilistic procedural programs can more naturally be modeled by recursive Markov chains ([EY04]), or equivalently, probabilistic pushdown automata ([EKM04]). A very rich theory emerges for these models. While our recent work solves a number of verification problems for these models, many intriguing questions remain open. © Springer-Verlag Berlin Heidelberg 2004.

关键词： Chains

来源：评论

学校读者我要写书评

暂无评论

Model checking probabilistic pushdown automata

Model checking probabilistic pushdown automata

引用

Annual Symposium on Logic in computer science

作者： J. Esparza A. Kucera R. Mayr Institute for Formal Methods in Computer Science University of Stuttgart Stuttgart Germany Institute for Formal Methods in Computer Science University of Stuttgart Germany Faculty of Informatics Masaryk University Brno Czech Republic Department of Computer Science Albert Ludwigs University of Freiburg Freiburg im Breisgau Germany

We consider the model checking problem for probabilistic pushdown automata (pPDA) and properties expressible in various probabilistic logics. We start with properties that can be formulated as instances of a generalized random walk problem. We prove that both qualitative and quantitative model checking for this class of properties and pPDA is decidable. Then, we show that model checking for the qualitative fragment of the logic PCTL and pPDA is also decidable. Moreover, we develop an error-tolerant model checking algorithm for general PCTL and the subclass of stateless pPDA. Finally, we consider the class of properties definable by deterministic Buchi automata, and show that both qualitative and quantitative model checking for pPDA is decidable.

关键词： Automata computer science Probabilistic logic Personal digital assistants Informatics Uncertainty Protocols Fault tolerant systems Asynchronous communication Concurrent computing

来源：评论

学校读者我要写书评

暂无评论

Formalization of UML object dynamics and behavior

Formalization of UML object dynamics and behavior

引用

IEEE International Conference on Systems, Man and Cybernetics

作者： T. Bouabana-Tebibel M. Belmesk Laboratory of System Conception Methods National Institute of Computer Science Algiers Algeria Collége Edouard Montpetit Longueuil Canada

UML has emerged as the industry standard for object-oriented modeling. However, it still lacks a well-defined semantic base enabling it to perform formal verification tasks. Our goal is to provide system designers a life cycle of software development integrating the UML user-friendliness and the Petri nets rigor and reliability. For this purpose, we propose a methodology to specify using UML and then to systematically verify and validate by way of the Petri nets. This methodology is based on a technique which derives colored Petri nets from UML object, statechart, collaboration and sequence diagrams. The proposed approach associates the formalization of the dynamics and the behavior of objects identified by identities and attribute values. A case study is provided to illustrate this technique.

关键词： Unified modeling language Petri nets Object oriented modeling Collaboration Formal specifications Laboratories Graphics Real time systems

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：