The Workflow Model Based On Petri Nets In The Research And Analysis

The Petri Net is an effective modeling tool for describing events with characteristics of concurrency and discretion. When Petri Net is used to model for workflow, the created models should be performed performance analysis in order that those models can describe enterprise management and process of task execution fully and systematically. Calculating the total equivalent service time is an important part in the research of the workflow model. However, in reality, the model tends to have big sizes and be very complex, which bring great difficulties to calculating the total service time.Considering above problems, this paper mainly studied reasonableness and correctness of modeling for workflow based on Petri Net, the details are as follows:Firstly, based on the four basic models of Petri Net, the detailed procedures and methods for simply stratifying complex workflow models were proposed, which made the complex workflow models easier to be analyzed quantitatively.Next, by the use of some mathematic means like order statistic, distribution function, probability density function and convolution integral etc., the calculating equivalent service time formula for three models, that is series models, parallel models and choice models, were deducted.And then, based on the describing workflow with Petri Net, a instance model of sale computer example was created. After layered simplification was done to the model, the deducted equivalent service time formula was used to calculate and analyze, which verified the reasonableness of the formula.Finally, the software ExSpect was used for the simulation of the sale computer model. Comparisons between academic calculation results and simulation results were carried out and analyzed.