The Research On High-level Petri-net-based Modeling And Analyzing Technologies

Workflow modeling and analyzing technology is the base of commercial organization, management, also the one of workflow management system (WFMS) design and realization. Before designing and developing WFMS, the first thing is to use a formalized method to describe business process correctly and clearly, which is the key to the realization of WFMS.The thesis begins from Petri nets'characteristics and formidable modeling superiority, and then in view of the limitation of traditional Petri nets, the high-level Petri net is proposed, which is a colored, timed and hierarchical expands. On the project characteristic basis, this paper brings forward the modeling thought of essential-bussiness-based workflow engine. Then, the thesis discusses the details of designing workflow model with it. Moreover, it makes a detailed exploration in how to carry out process definition to adopt the standard language XPDL. In this application, we need to solve two key questions: transaction processing and concurrent controlling. After the introduction of workflow transaction-processing logic, the thesis proposes the"compensate-substitute transaction processing logic", which is combined with Sagas and Contracts model thoughts and solves the long transaction problem effectively. To avoid concurrent accessing conflicts to those shared resources in workflow system, this paper also puts forward"the lock tie mechanism based on PRI"to solve this problem.The article debates two workflow model analyzing technologies: qualitative analysis and quantitative analysis. It also gives the accessibility analysis, the queuing theory and structure analysis in detail. The process resolving layer-based is proposed on the combinable identity of workflow basis. On the basis of workflow net, this thesis advances workflow stochastic Petri nets and Continuous-Time Markov Chain. According to quoting the simplification method based on the stochastic Petri nets and the approximate analysis method, this paper calculates process/activity average execution time. In addition, it describes simulation analysis method and concrete application by a series of examples. Finally, the thesis summarizes the research work, points out the disadvantages of this paper and gives some ideas for the further work. Keyword:Workflow, Petri nets, Workflow Modeling, Process Definition,...