Study Of Key Techniques In WEB-based Workflow Management Systems

Workflow management systems(WfMS) help to define and carry out these business processes in a heterogeneous and distributed environment. They make sure that within a business process the right activity is performed at the right time, at the right place, by the right people, with the right data, using the right tools. Applications that are built using workflow management systems are called workflow-based applications.With the development of network technologies such as Internet/Intranet/WWW, they provide the ideal design environment to the WfMS. It is easily to integrate varieties of distributing information resources in order to improve the efficiency of management systems by WEB-based WfMS. This thesis introduces the principle of design and method of realization of a WEB-based WfMS. Also this thesis provides some key studies of the WEB-based WfMS.Firstly, the WEB environment for running WfMS is described, and the idea of design and the blue print of implement are provided for WEB application framework. This WEB application framework extends the system structure of traditional tri-layer WEB structure to the five-layer model.Secondly, this thesis introduces a XML-based workflow reference model to resolve the problem of transporting data among dissimilar platform in workflow environment. This reference model uses the reference of WfMC workflow reference model. It also introduces a implement plan based on bus mechanism which uses XML to envelop the process of transporting data.In the end, it is discussed the design and implement of which correlative with workflow engine such as process definition model, scheming task and task dispatch. To solve the problem of concurrent collision while scheming task, this paper discusses a solution which uses locking technologies used by priority.