Process Algebra In The Workflow Application

With the emergence of Internet/Intranet, computer and its application fields are having a profound revolution. Computer application is towards a cooperative way. At the same time, distribution technology is becoming more and more mature. Workflow management system has changed from creating a paper-free office environment initially to integrating company information environment and executing processes automatically. These changes bring workflow technology to a new development phrase, and make us study workflow profoundly and widely.Workflow model is the base of workflow application systems, which has an important role and whose quality affects workflow application scope and the ability to adapt easily variety. Now there is a lack of formal workflow to support process definition, evolution and analysis.So we apply process algebra to modelling workflow. Process algebra has precise formal semantics, rigorous math foundation and abundant calculation ways. After describing some common workflow patterns in CSP, we can see that the concepts of process algebra are easy, its ability of description is strong, and it can describe control flow in workflow applications well and thus can solve the problem of modeling complex systems. After modeling, we use model checker to check some of its key properties, which can guarantee the system's correctness and reliability.When using process algebra to model workflow, we only consider its formal semantics and its control flow. So when executing, we use some state information to identify its state and their dependence relations. We also apply proposition formulas to handle exceptions, which gives us much convenience to implementation.At last, according to the previous theory, we implemented a Hospital Booking System. This system uses light workflow engineer to allocate, manage and monitor the execution of tasks. For concurrent control we set User Trust Value to avoid robbing priority by registering many times, which guarantees justice quite well.