Petri网的公平性及分析

Overview: Fairness in Petri Net,Analysis and Application

公平性是反映了在资源竞争时Petri网模型系统中行为的无饥饿性。公平关系分为三个层次,即公平关系、弱公平关系和广义公平关系,并衍生出亚公平关系和准公平关系;对应的系统网模型包括公平网、弱公平网,亚公平网等。同时相对公平网严格要求,系统的Petri网模型存在分组公平和局部公平,反映了网系统局部行为的公平关系。在Petri网模型简化和子网合成时的公平性保性,反映简化和合成后资源共享的保持特性。综述了以上公平性及判定方法,介绍公平性在系统中的应用,并给出公平性的细化定义和同步距离的关系,展望了Petri网公平性在连续系统与离散事件系统中的未来研究方向和应用难点,对公平关系今后的研究具有一定的指导意义。

Fairness in Petri net is an important characteristic which expresses starvation-free characteristic of actions in the system model.The fair relations of the transitions in the system model are divided to three levels which are defined as fair relations,weak fair relations and extended fair relations in Petri net.The fairness of the model,the distinguishing methods and the application in distribute system were reviewed.Finally,fair relations were more refined,relation with synchronic distance was analyzed,and the research direction and application problems in the continuous systems and discrete event systems were discussed.