Workflow Patterns

Differences in features supported by the various contemporary commercial workflow management systems point to different insights of suitability and different levels of expressive power. The challenge, which we undertake in this paper, is to systematically address workflow requirements, from basic to complex. Many of the more complex requirements identified, recur quite frequently in the analysis phases of workflow projects, however their implementation is uncertain in current products. Requirements for workflow languages are indicated through workflow patterns. In this context, patterns address business requirements in an imperative workflow style expression, but are removed from specific workflow languages. The paper describes a number of workflow patterns addressing what we believe identify comprehensive workflow functionality. These patterns provide the basis for an in-depth comparison of a number of commercially availablework flow management systems. As such, this paper can be seen as the academic response to evaluations made by prestigious consulting companies. Typically, these evaluations hardly consider the workflow modeling language and routing capabilities, and focus more on the purely technical and commercial aspects.     

基于J2EE的交互式工作流管理系统

针对目前工作流系统在描述能力、跨平台能力和交互性上的不足,该文提出了一个基于J2EE技术的交互式工作流管理系统,系统使用分层描述的方法将复杂的业务过程分解为多个简单的业务过程,通过事件驱动机制来实现分解后的过程间的交互,可以完成与原来复杂过程相同的业务逻辑。实际应用表明,该系统在提高描述能力、降低建模复杂性、增强模型间交互能力及跨平台能力方面都有较明显优点。     

VIVACE: A framework for the systematic evaluation of variability support in process-aware information systems

ContextThe increasing adoption of process-aware information systems (PAISs) such as workflow management systems, enterprise resource planning systems, or case management systems, together with the high variability in business processes (e.g., sales processes may vary depending on the respective products and countries), has resulted in large industrial process model repositories. To cope with this business process variability, the proper management of process variants along the entire process lifecycle becomes crucial.ObjectiveThe goal of this paper is to develop a fundamental understanding of business process variability. In particular, the paper will provide a framework for assessing and comparing process variability approaches and the support they provide for the different phases of the business process lifecycle (i.e., process analysis and design, configuration, enactment, diagnosis, and evolution).MethodWe conducted a systematic literature review (SLR) in order to discover how process variability is supported by existing approaches.ResultsThe SLR resulted in 63 primary studies which were deeply analyzed. Based on this analysis, we derived the VIVACE framework. VIVACE allows assessing the expressiveness of a process modeling language regarding the explicit specification of process variability. Furthermore, the support provided by a process-aware information system to properly deal with process model variants can be assessed with VIVACE as well.ConclusionsVIVACE provides an empirically-grounded framework for process engineers that enables them to evaluate existing process variability approaches as well as to select that variability approach meeting their requirements best. Finally, it helps process engineers in implementing PAISs supporting process variability along the entire process lifecycle.     

基于过程模型的工作流执行语义研究

针对现有工作流建模语言难以兼顾语言的可理解性、执行语义的形式化和描述维度的单一性等问题,提出利用可视化的过程模型作为工作流建模语言。过程模型能从过程、数据、资源、组织等多个角度描述企事业的业务工作流程。根据过程模型的语法和工作流系统的特点,定义形式化执行语义,为过程模型的分析、验证和执行提供理论依据。     

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.     

一个面向工作流的过程建模平台的实现

在工作流系统中，对业务过程的抽象需要过程描述语言和过程建模工具的支持。介绍了一种过程描述语言的基本结构，基于这种描述语言的过程建模平台的系统设计、应用实例以及发展方向。     

Model-as-you-go: An Approach for an Advanced Infrastructure for Scientific Workflows

Most of the existing scientific workflow systems rely on proprietary concepts and workflow languages. We are convinced that the conventional workflow technology that is established in business scenarios for years is also beneficial for scientists and scientific applications. We are therefore working on a scientific workflow system based on business workflow concepts and technologies. The system offers advanced flexibility features to scientists in order to support them in creating workflows in an explorative manner and to increase robustness of scientific applications. We named the approach Model-as-you-go because it enables users to model and execute workflows in an iterative process that eventually results in a complete scientific workflow. In this paper, we present main ingredients of Model-as-you-go, show how existing workflow concepts have to be extended in order to cover the requirements of scientists, discuss the application of the concepts to BPEL, and introduce the current prototype of the system.     

Enhancing Workflow Management in the Manufacturing Information System of a Small-Medium Enterprise: An Agent-Based Approach

One shortcoming of manufacturing information systems is their inability to integrate and to enhance different information and related functionalities, such as those found in workflow management. Software agents, once added as a new software layer to an existing system, can overcome this problem. Of the fields applying software agent technology, manufacturing, and especially workflow management, is perhaps the most promising for the development of distributed systems. This potential is reflected in the several ongoing research projects that focus on workflow management and share the final aim of integrating and coordinating plant and business activities.The approach presented in this paper can be regarded as an agent-based architecture applied to an existing workflow management system in order to manage new functionalities, e.g., customer relationship management in electronic commerce. This approach is particularly suitable for small medium enterprises with simple manufacturing information requirements and simple or nonexistent computer based workflow management.The model and some important features of system implementation, such as the knowledge modeling graphical user interface, the communication model, and a simple practical example of the architecture's use, are described.     

Patterns-based evaluation of open source BPM systems: The cases of jBPM,OpenWFE, and Enhydra Shark

In keeping with the proliferation of free software development initiatives and the increased interest in the business process management domain, many open source workflow and business process management systems have appeared during the last few years and are now under active development. This upsurge gives rise to two important questions: What are the capabilities of these systems? and How do they compare to each other and to their closed source counterparts? In other words: What is the state-of-the-art in the area?. To gain an insight into these questions, we have conducted an in-depth analysis of three of the major open source workflow management systems – jBPM, OpenWFE, and Enhydra Shark, the results of which are reported here. This analysis is based on the workflow patterns framework and provides a continuation of the series of evaluations performed using the same framework on closed source systems, business process modelling languages, and web-service composition standards. The results from evaluations of the three open source systems are compared with each other and also with the results from evaluations of three representative closed source systems: Staffware, WebSphere MQ, and Oracle BPEL PM. The overall conclusion is that open source systems are targeted more toward developers rather than business analysts. They generally provide less support for the patterns than closed source systems, particularly with respect to the resource perspective, i.e. the various ways in which work is distributed amongst business users and managed through to completion.     

Fundamentals of control flow in workflows

Abstract. Although workflow management emerged as a research area well over a decade ago, little consensus has been reached as to what should be essential ingredients of a workflow specification language. As a result, the market is flooded with workflow management systems, based on different paradigms and using a large variety of concepts. The goal of this paper is to establish a formal foundation for control-flow aspects of workflow specification languages, that assists in understanding fundamental properties of such languages, in particular their expressive power. Workflow languages can be fully characterized in terms of the evaluation strategy they use, the concepts they support, and the syntactic restrictions they impose. A number of results pertaining to this classification will be proven. This should not only aid those developing workflow specifications in practice, but also those developing new workflow engines. Received 16 January 2001 / 13 November 2002 This research is supported by an ARC SPIRT grant “Component System Architecture for an Open Distributed Enterprise Management System with Configurable Workflow Support” between QUT and Mincom.     

An overview of workflow management: From process modeling to workflow automation infrastructure

Today's business enterprises must deal with global competition, reduce the cost of doing business, and rapidly develop new services and products. To address these requirements enterprises must constantly reconsider and optimize the way they do business and change their information systems and applications to support evolving business processes. Workflow technology facilitates these by providing methodologies and software to support (i) business process modeling to capture business processes as workflow specifications, (ii) business process reengineering to optimize specified processes, and (iii) workflow automation to generate workflow implementations from workflow specifications. This paper provides a high-level overview of the current workflow management methodologies and software products. In addition, we discuss the infrastructure technologies that can address the limitations of current commercial workflow technology and extend the scope and mission of workflow management systems to support increased workflow automation in complex real-world environments involving heterogeneous, autonomous, and distributed information systems. In particular, we discuss how distributed object management and customized transaction management can support further advances in the commercial state of the art in this area. Recomended by: Omran Bukhres and e. Kühn     

Standards-based approaches to B2B workflow integration

E-business automates the overall activities of a company and allows distributed systems to communicate their information. Process automation and information sharing improve a company’s productivity and responsiveness, while Business-to-Business (B2B) workflow systems electronically aid the progress of business processes among trading partners, and also help companies to monitor and administrate their process execution. This study analyzes the technologies and standards for B2B workflow integration, and extracts a reference model for B2B workflow integration. Based on the reference model, three approaches to B2B workflow integration will be introduced here. In addition, we have developed a prototype system of one approach and have illustrated an example for B2B workflow integration. The result of our research can help business partners understand the workflow standards and the messaging technologies for B2B workflow integration, and also help them understand how to implement workflow integration systems that are appropriate to their e-business environments.     

一种改进的基于模板的工作流过程定义方法

随着工作流技术在企业业务流程管理中的广泛应用,人们对工作流管理系统的描述能力和动态变更能力提出了更高的要求。针对目前的工作流过程定义方法在这两个方面的不足,本文提出了一种基于模板机制的工作流过程定义方法。该方法在现有的工作流过程定义模型的基础上,加入了新的过程模板和活动接口元素。本文由此扩展了工作流过程定义语言,增加了支持模板描述的机制。实际应用的结果表明,该方法和现有的工作流过程定义方法相比,显著提高了模型描述能力,使得过程模型具有了较强的可重用性和可扩展性,并具备了一定的动态变更能力。     

基于Internet支持群组决策的工作流管理系统的设计与实现

工作流管理是ＣＳＣＷ中的一个重要领域．采用工作流管理系统企业能够简单快速地实现业务处理过程,迅速适应市场的变化,从而获得更好的经济效益．本文介绍了一个基于Ｉｎｔｅｒｎｅｔ并支持群组决策的工作流管理平台——ＮＥＵＷｏｒｋ的设计模型,讨论了ＮＥＵＷｏｒｋ实现中的几个关键问题——基于功能网的图形化工作流模型建立工具,协调机制的实现及群组决策支持的实现．     

面向生物信息的网格工作流开发与运行环境

网格工作流系统通过组合网格计算结点上的资源为生物计算等领域的复杂计算任务提供了支持。为了解决已有系统中用户需要对流程语言细节有较深入了解以及操作和配置较为复杂等问题,设计和实现了面向生物信息领域的网格工作流开发与运行环境。生物信息领域的用户使用该系统,可以通过web的方式实现对生物计算模型较高抽象层次的在线流程设计、流程作业的提交、作业状态的管理以及计算结果的查看等操作。最后通过生物计算领域的基因计算任务说明了系统对生物信息学应用的支撑功能。