Research On The Use Of Colored Timed Petri Net And Stochastic Petri Net

Petri Net is a formal, graphical, executable technique for the specification and analysis of concurrent, discrete-event dynamic systems. However, when modeling complicated control systems, basic Petri net may lead to the problem of node number explosion. Colored Timed Petri Net(CTPN) is a way to solve this problem. Multi-paradigm modeling, concerned with the coupling of and transformation between models described in different formalisms, can give a representation of models in diverse formalisms, at different levels of abstraction, and the behavior-conserving transformation between the formalisms is demonstrated. So modeling of CTPN derived from rule description method, which takes advantages of two modeling methods, is presented. And also the method is illustrated through modeling process of auto-body control system, which will help to model, analyze and simulate for complicated systems.Workflow management techniques were developed in early 1990s. Workflow is the automation of a business process in whole or part. To achieve the function of workflow management, the business process must be abstracted from the real world and described by a kind of formal method. The result is workflow model. As a kind of graphical and mathematical modeling tools, Petri Net is applicable to the modeling requirement of workflow. A method of modeling for workflow based on Generalized Stochastic Petri Net (GSPN) is proposed, the workflow definition of Workflow Management Coalition is mapped to generalized stochastic workflow net. The validity and reliability is checked using reachable graph method. By utilizing the equivalence relation between GSPN and Markov chain, a method of combining GSPN and Markov chain is used to analyze the performance of workflow. The effectiveness of this method is verified by an application case.