基于Bossa的工作流管理系统的开发方法

Petri网作为一个比较好的过程建模技术,在工作流模型的描述中有着一定的优势。基于Petri网的工作流模型如何投入到具体的工作流管理系统中,需要选择合适的工作流引擎,此引擎必须要能够完全支持基于Petri网的工作流模型的定义,Bigbross Bossa是各种工作流引擎中为数不多的采用Petri网来定义工作流的引擎之一,该文就Bossa工作流引擎的使用方法进行探讨和描述。     

着色Petri网在工作流建模中的应用

工作流建模是工作流管理系统进行工作流管理所必不可少的一个环节。而Petri网以其严格的数学基础、成熟的分析方法和工具而日益得到广泛的应用。本文介绍了着色Petri网在工作流建模中的作用，然后对一个具体的业务流程分别用经典Petri网和着色Petri网建立了过程模型并进行了比较。     

模糊着色Petri网及其在工作流建模中的应用

Petri网是当前工作流建模中广泛采用的工具之一，针对工作流过程定义中模糊信息的描述和处理问题，提出模糊着色Petri网的描述方法，并给出基于模糊着色Petri网的推理过程，最后给出一个简单业务流程的基于模糊着色Petri网的工作模型，并对该模型进行了分析。     

Petri网在工作流引擎中的应用分析

目前对工作流技术进行深入的研究对于提高企业的信息化程度、运行效率以及竞争能力都有重要的意义,而工作流引擎是整个工作流管理系统的核心。该文首先介绍了工作流引擎的定义和5个重要接口,以及Petri网的概念和建模优势。其次比较了Open WFE,jBpm,YAWL,Bossa等开源工作流引擎,指出基于Petri网调度算法的工作流引擎所具有的优势。在此基础上重点分析了Bossa引擎的调度算法,最后对Petri网在工作流引擎中的使用提出展望。     

UML和着争PETRI网在物资采购建模中的应用

本文讨论了如何用当今流行的建模语言UML对系统进行建模，列出了一个完整的物资采购实例，通过这个实例分析建模的全部过程，提出UML作为建模语言本身存在的问题，并就存在的问题提出了着色Petri的解决方案。将UML和Petri网联合起来对系统进行建模。     

基于着色Petri网的工作流模型研究

针对传统Petri网建模方法的不足,研究了通过资源结构建模的工作流建模方法.在着色Petri网的基础上提出资源/任务网(R/T-net),并给出基于R/T-net的工作流建模过程.R/T模型能够有效地实现产品数据结构和过程结构的统一,资源流对任务流的控制以及模型的仿真.     

UML和着色PETRI网在物资采购建模中的应用

本文讨论了如何用当今流行的建模语言UML对系统进行建模,列出了一个完整的物资实例,通过这个实例分析建模的全部过程,提出UML作为建模语言本身存在的问题,存在的问题提出了着色Petri的解决方案.将UML和Petri网联合起来对系统进行建模     

基于Petri网的建设工程项目实施阶段工作流建模与仿真

构建一个能够准确表达实施过程系统性、动态性和不确定性的工作流模型是实现建设工程项目实施阶段工作流管理与控制的有效途径。在对建设工程项目实施阶段工作流模型特点分析及工作流概念模型构建的基础上,基于分层赋时着色Petri网构建建设工程项目实施阶段工作流模型。通过运行该工作流模型,能够获得实施阶段的信息流、资源流、异常处理、持续时间等抽象内容,不仅为实现建设项目实施阶段的工作流管理与控制提供有力的方法支持,同时也是Petri网建模技术在建设工程领域中的应用拓广。借助CPN Tools仿真平台,以一般工业与民用建筑的实施阶段为例进行工作流模型的构建与仿真,验证了基于分层赋时着色Petri网构建建设工程项目实施阶段工作流模型的正确性和有效性。     

基于面向对象Petri网的工作流建模及性能分析

工作流技术作为一种过程建模和过程管理的核心技术，在计算机应用领域获得了迅速的发展。介绍了工作流技术；提出了将面向对象建模技术融入Petri网模型所形成的面向对象Petri网，并讨论了建立基于面向对象Petri网的工作流模型的步骤；运用面向对象Petri网建立了某制造企业的产品方案处理流程的工作流模型，并运用性能等价公式对工作流模型的性能进行了分析。     

基于着色工作流网的工作流模型的设计与实现

本文在扩展Petri网的基础上，提出了一个新的工作流模型——基于着色工作流网的工作流模型，并对其进行了详细设计。在此模型的基础上，本文实现了一个可视化的工作流建模工具，设计人员通过该工具建立业务过程，并根据模型的定义保存业务过程定义。     

基于UML的业务流程模型分析方法研究

基于UML的业务流程建模方法是业务流程建模领域中的一种重要方法,该文对基于UML的业务流程建模方法中的重要工具活动图进行形式化定义,给出了基于活动图的业务流程模型与工作流网之间的规范化转换方法,从而可以分析和检验基于UML的业务流程模型的静态和动态属性。     

Coloured Petri Nets and CPN Tools for modelling and validation of concurrent systems

Coloured Petri Nets (CPNs) is a language for the modelling and validation of systems in which concurrency, communication, and synchronisation play a major role. Coloured Petri Nets is a discrete-event modelling language combining Petri nets with the functional programming language Standard ML. Petri nets provide the foundation of the graphical notation and the basic primitives for modelling concurrency, communication, and synchronisation. Standard ML provides the primitives for the definition of data types, describing data manipulation, and for creating compact and parameterisable models. A CPN model of a system is an executable model representing the states of the system and the events (transitions) that can cause the system to change state. The CPN language makes it possible to organise a model as a set of modules, and it includes a time concept for representing the time taken to execute events in the modelled system. CPN Tools is an industrial-strength computer tool for constructing and analysing CPN models. Using CPN Tools, it is possible to investigate the behaviour of the modelled system using simulation, to verify properties by means of state space methods and model checking, and to conduct simulation-based performance analysis. User interaction with CPN Tools is based on direct manipulation of the graphical representation of the CPN model using interaction techniques, such as tool palettes and marking menus. A license for CPN Tools can be obtained free of charge, also for commercial use.     

Implementing Coloured Petri Nets Using a Functional Programming Language

Coloured Petri Nets (CPNs) are a graphically oriented modelling language for concurrent systems based on Petri Nets and the functional programming language Standard ML. Petri Nets provide the primitives for modelling concurrency and synchronisation. Standard ML provides the primitives for modelling data manipulation and for creating compact and parameterisable CPN models.Functional programming and Standard ML have played a major role in the development of CPNs and the CPN computer tools supporting modelling, simulation, verification, and performance analysis of concurrent systems. At the modelling language level, Standard ML has extended Petri Nets with the practical expressiveness required for modelling systems of the size and complexity found in typical industrial projects. At the implementation level, Standard ML has been used to implement the formal semantics of CPNs that provide the theoretical foundation of the CPN computer tools.This paper provides an overview of how functional programming and Standard ML are applied in the CPN modelling language and the supporting computer tools. We give a detailed presentation of the key algorithms and techniques used for implementing the formal semantics of CPNs, and we survey a number of case studies where CPNs have been used for the design and analysis of systems. We also demonstrate how the use of a Standard ML programming environment has allowed Petri Nets to be used for the implementation of systems.     

地理空间约束的业务流程建模方法

明晰了受地理空间约束的业务流程的两个基本概念:地理位置与地理空间信息.首先,提出了地理空间约束思想,分析了地理空间约束的内涵,并在工作流元模型的知识基础上构建了地理空间约束的UML语义框架;其次,以形式化的方式提出了地理空间约束的业务流程建模方法(LAWF-net),并描述了LAWF-net模型转化为CPN可执行模型的规则,探讨了地理空间约束对流程建模的影响;最后,通过案例结合GIS系统来扩展CPN Tools,不仅验证了LAWF-net建模方法的可行性,而且实现了地理空间约束的业务流程的可视化.     

YAWL: yet another workflow language

Based on a rigorous analysis of existing workflow management systems and workflow languages, a new workflow language is proposed: yet another workflow language (YAWL). To identify the differences between the various languages, we have collected a fairly complete set of workflow patterns. Based on these patterns we have evaluated several workflow products and detected considerable differences in their ability to capture control flows for non-trivial workflow processes. Languages based on Petri nets perform better when it comes to state-based workflow patterns. However, some patterns (e.g. involving multiple instances, complex synchronisations or non-local withdrawals) are not easy to map onto (high-level) Petri nets. This inspired us to develop a new language by taking Petri nets as a starting point and adding mechanisms to allow for a more direct and intuitive support of the workflow patterns identified. This paper motivates the need for such a language, specifies the semantics of the language, and shows that soundness can be verified in a compositional way. Although YAWL is intended as a complete workflow language, the focus of this paper is limited to the control-flow perspective.     

基于XML的Petri网流程描述及构造

工作流过程定义可以采用不同的建模方法,由于Petri网有坚实的理论基础和易于使用的图形表示,因而是一种理想的建模和分析工具,XPDL是基于XML技术的工作流过程定义语言。文中提出了六种基本的Petri网流程模块,给出了由Petri网向XPDL转换的方法以及由XPDL构造Petri网的方法。     

延迟时间Petri网的验证分析

延迟时间Petri网（Delay Time Petri Nets，DTPN）是一类重要的时间扩展Petri网系统，解决了其他时间扩展Petri网（如时间Petri网）在保存时间约束时所面临的困难。可调度验证的目的是验证工作流模型时间约束的合理性，对流程实例的时间可达性进行仿真。提出一种基于DTPN的时间约束工作流验证分析方法。给出了DTPN的相关定义，并结合工作流控制结构描述了变迁可触发的时间条件；提出了DTPN触发点的概念以及基于此的验证分析算法；简要分析了DTPN的特性。DTPN的研究丰富完善了现有时间Petri网体系，具有积极的意义。     

Verifying workflow processes: a transformation-based approach

Workflow modeling is a challenging activity and designers are likely to introduce errors, especially in complex industrial processes. Effective process verification is essential at design time because the cost of fixing errors during runtime is substantially higher. However, most user-oriented workflow modeling languages lack formal semantics that hinders such verification. In this paper, we propose a generic approach based on the model transformation to verify workflow processes. The model transformation includes two steps: first, it formalizes the desirable semantics of each modeling element; secondly, it translates a workflow process with clear semantics to an equivalent Petri net. Thus, we can verify the original workflow process using existing Petri net theory and analysis tools. As a comprehensive case study, verifying workflow processes in an industrial modeling language (TiPLM) is presented. Experimental evaluations on verifying real-world business processes validate our approach.     

基于面向对象时间Petri网的密码协议分析

利用面向对象技术和时间Petri网的优点,提出一种基于面向对象时间Petri网的密码协议分析方法。该方法可以降低建模复杂性和计算复杂性,提高建模效率,实现时间Petri网的高度模块化,能更好地适应密码协议分析过程中的重组和扩充。实例分析结果证明了该方法的有效性。     

A methodology to specify three-dimensional interaction using Petri Nets

This work presents a methodology to formally model and to build three-dimensional interaction tasks in virtual environments using three different tools: Petri Nets, the Interaction Technique Decomposition taxonomy, and Object-Oriented techniques. User operations in the virtual environment are represented as Petri Net nodes; these nodes, when linked, represent the interaction process stages. In our methodology, places represent all the states an application can reach, transitions define the conditions to start an action, and tokens embody the data manipulated by the application. As a result of this modeling process we automatically generate the core of the application's source code. We also use a Petri Net execution library to run the application code. In order to facilitate the application modeling, we have adapted Dia, a well-known graphical diagram editor, to support Petri Nets creation and code generation. The integration of these approaches results in a modular application, based on Petri Nets formalism that allows for the specification of an interaction task and for the reuse of developed blocks in new virtual environment projects.