【摘要】 基于路增益概念 ,证明了无回路加权事件图位置不变量的存在性 ,并给出了其位置不变量集合的表达形式和最小位置不变量的计算方法。讨论了两个 Petri网基于位置并的位置不变量 ,通过把无回路 Petri网分解成一些加权事件图基于位置的并 ,给出了无回路 Petri网位置不变量的存在性判别及确定的几何方法更多还原

【Abstract】 Based on the concept of path gain the existance of loop free weighted event graph place invariant is proved and the form of its place invariant and the minimum place invariant are embodied.The place invariant of Petri net which is merged by two Petri nets on places is discussed. A geometrical approach to compute place invariant and judge its existence is presented via decomposing loop free Petri net into some weighed event graphs merged on places.更多还原