基于模糊时间Petri网的网络计划模型

A Model of Project Planning Based on Fuzzy-Timing Petri Nets

针对工程计划中工序作业时间的不确定性以及传统网络计划方法缺乏数学表达能力等问题 ,提出了用模糊时间Petri网 (fuzzy timingPetrinet,FTPN)表达工程计划、求取关键路径的新模型。在给出了时间模糊数、FTPN的形式化描述、FTPN触发规则及数学特性和工程计划FTPN建模规则的基础上 ,把求取工程计划的关键路径问题转化为一个基于FTPN代数方程求取特定标识问题 ,在此基础上 ,进一步计算了工程计划在约束条件下按时完工的可能性。结果表明 ,所提出的模型既能正确、直观地表达工程计划问题 ,又能形式化描述、计算工程计划关键路径问题。

In view of the time uncertainty of activities and the lack of a formal description of project planning, a new model is proposed based on the fuzzy-timing Petri net(FTPN). On the basis of the formal definition, trigger rules and mathematical properties, FTPN is used to represent the project planning clearly, and the problem of critical path is turned into a special mark of FTPN. The possibility of project completion is also discussed in the time restriction. The conclusion is drawn that FTPN can not only be used to express the project planning properly and clearly, but also give a formal representation and computation easily.