Modeling and Verification of Workflow Graphs
Modeling and Verification of Workflow Graphs
复制标题
工作流程图的建模和验证
DOI：
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发表时间：
1996
期刊：
影响因子：
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通讯作者：
M. Orlowska
中科院分区：
文献类型：
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作者：
Wasim Sadiq;M. Orlowska
近年来，工作流技术一直是一个活跃的研究领域。工作流的概念建模是了解业务流程的第一步，也可以说是最重要的一步。定义良好的工作流概念模型有助于开发有效的工作流应用程序。提出了一种工作流图形化建模技术。我们介绍了四个图形化建模对象：任务、条件、同步器和流。这些任务代表了主要的建模概念，并可以通过几个通用的和特定于工作流的特征进行分类，其中一些特征已经在本文中确定。使用四个建模对象，标识以下工作流建模构造：排序、替代、排他连接、并发、同步、迭代、开始/停止、嵌套和偶发。在构建大型工作流规范时，很容易陷入错误情况。我们提出了一组约束以确保工作流规范的正确性。简要介绍了任务补偿和任务结构的概念。我们还应用所提出的概念建模技术对一个处理某大学研究生录取过程的文档工作流应用程序进行了建模。本文介绍的概念被应用于一个用于工作流图建模和语法验证的CASE工具的开发。1工作流程在当今的商业环境中，计算机被广泛用于实现业务流程的自动化。这些组织被划分为几个职能领域，并为每个划分的领域开发信息系统。在开发和实施任何信息系统之前，了解业务流程的操作是至关重要的。为此，使用了业务数据和流程建模方法。为了对数据需求进行建模，采用了实体关系建模等概念数据建模方法。流程建模方法(如数据流图)用于识别业务流程并捕获它们之间的信息流。[GHS95]概述了业务流程建模、工作流管理方法和产品，以及当前工作流领域的研究方向。职能业务领域内的活动可以是手动的、自动的或两者的组合。对于大型组织来说，支持功能区的系统运行在异构性和分布式的硬件和软件环境中。一般来说，每个系统本身也是按照模块化方法开发的。所有这些模块和系统相互通信和协调，以实现其功能目标。这些自动或手动活动的协调历来是手动执行的。近年来，已经探索了自动化这些不同处理活动的执行协调的可能性，并称之为工作流。[WfMC96]将工作流定义为“整个或部分业务流程的自动化，在此过程中，文档、信息或任务根据一组程序规则从一个参与者传递到另一个参与者以进行操作。”工作流代表从一个处理实体到另一个处理实体的组织信息流，无论是手动的还是自动的。处理实体使用该信息来完成分配的任务。这些任务从前面的任务中获取一些信息，基于使用所分配的处理实体的服务接收到的信息执行一些工作，并继续执行工作流中的下一个任务。例如，在面向批量的会计系统中，其中一项任务是为出纳员收到的每一笔付款准备一份正式收据。这是一项人工任务，其处理实体是出纳员。白天，收银员会反复为不同的客户执行这项任务。一天结束时，他或她
The workflow technology has been an active area of research for the past few years. The conceptual modeling of workflows is the first, and arguably the most important, step towards understanding business processes. A well defined workflow conceptual model leads to the development of an effective workflow application. This paper presents a graphical modeling technique for workflows. We introduce four graphical modeling objects: tasks, conditions, synchronizers, and flows. The tasks represent the primary modeling concept and could be classified through several generic and workflow specific characteristics, some of which have been identified in this paper. Using the four modeling objects, the following workflow modeling constructs are identified: ordering, alternative, exclusive join, concurrency, synchronization, iteration, start/stop, nesting, and contingency. It is possible to easily get into error situations while building large workflow specifications. We present a set of constraints for ensuring the correctness of workflow specifications. A brief introduction to the concept of task compensation and task structures is given. We also apply the proposed conceptual modeling technique to model an example document workflows application for handling postgraduate admission process of a university. The concepts introduced in this paper are applied as a foundation to the development of a CASE tool for the modeling and syntactical verification of workflow graphs. 1 Workflows In today’s business environments, computers are extensively used for automating business processes. The organizations are partitioned into several functional areas and information systems are developed for each of the divided areas. It is essential to understand the operations of business processes before any information systems are developed and implemented. For this purpose, business data and process modeling methodologies are used. To model the data requirements, conceptual data modeling methodologies like entity-relationship modeling are applied. The process modeling methodologies, like data flow diagrams, are applied to identify business processes and capture the flow of information among them. The [GHS95] provides an overview of business process modeling, workflow management methodologies and products, and current research directions in the field of workflows. The activities within a functional business area are either manual, automated, or a combination of both. For big organizations, the systems supporting the functional areas run in heterogeneous and distributed hardware and software environments. Generally, each system itself is also developed following a modular approach. All these modules and systems communicate and coordinate with each other to achieve their functional objectives. The coordination of these automated or manual activities has historically been performed manually. In recent years, the possibility of automating the execution coordination of these different processing activities has been explored and called workflows. The [WfMC96] defines workflows as “The automation of a business process, in whole or part, during which documents, information or tasks are passed from one participant to another for action, according to a set of procedural rules.” The workflows represent the organizational flow of information from one processing entity , either manual or automated, to another. The processing entities use this information to accomplish assigned tasks. These tasks take some information from the preceding tasks, perform some work based on the information received using the services of the assigned processing entities, and proceed to the next tasks in the workflow. For example, in a batch oriented accounting system, one of the tasks is to prepare an official receipt for each payment received by the Cashier. This is a manual task and its processing entity is the Cashier. During the day, the Cashier would repeatedly perform this task for different customers. At the end of the day, he or she