中文摘要：

为提高网系统的日常安全管理水平,实现系统重要节点的重点监管,以基本Petri网系统为对象,提出考虑相继故障的节点重要性评价方法。先将变迁间的关联结构关系划分为串联顺序、选择关联和非关联3种,并给出相应的形式化判别方法和变迁节点失效传递规则。在此基础上,建立基本Petri网系统中变迁节点的全局重要性评价指标及算法。最后以高速铁路中临时限速实施过程为算例,进行方法验证。结果表明：所建立的Petri网节点重要性评价方法能够体现网络系统的相继故障特性,并且能够解决节点删除法造成的网络不连通性问题。

英文摘要：

To improve system daily safety management level and realize that more important nodes can get more attention, considering the cascading failures, a node evaluation method was worked out for elementary Petri nets. First of all, associated structure types between transition nodes were divided into three types such as sequential structure, alternative structure and reserve structure. Then the formal judgmental conditions and the consequences after any node failure occurs considering cascading failures were given respectively. Lastly, an algorithm was put forward for calculating the importance evaluation index. The complexity of the algorithm is much lower than that of approaches using shortest path such as betweenness. A numerical example of temporary speed constraint commands in high-speed railway was given at the end to verify the functional correctness and performance of the evaluation method. The results show that the evaluation method based on Petri nets can reflect system cascading failure and avoid splitting the network caused by using the node deletion method ,for example.