The Reserch And Application Of Railway Transportation Safety Based On Petri Net

The railway transportation is a main mean of transportation in our country. Safety and punctuality are two basic requirements of railway transportation. But with the progress of railway modernization in our country, rapid development of the railway system and the increasing train operation speed and density, the contradictions of railway transport capacity and traffic volume are increasingly prominent. Railway transportation is facing unprecedented challenges and severe tests not only in security but also in punctuality. How to utilize the limited resources of railway to achieve efficient, safe and punctual railway transport is the core problem to promote the development of railway transportation industry. There are many unpredictable human or non-human factors in the process of train running. It results in the train delays and even collision accidents as the train cannot run accurately according to the train diagram. So in order to avoid such accidents, it is in urgent need of the accurate and punctual train scheduling.In this paper, an extended fuzzy Petri net (EFPN) was proposed in order to ease the current situation of train delays. On the basis of the critical factors which can usually result in the train delays, a causal relationship was given and a train delays causation analysis model based on EFPN was built after simulating and analyzing the causality of the given factors. EFPN reasoning algorithm was used to analyze and calculate the validity of the factors which lead to train delays. The factor with highest validity is the most critical factor.A fuzzy time characteristic Petri net (FTCPN) was proposed to solve the problem of the train delays and collision accidents according to the train diagram during the train running. Compared with current research on the safety and punctuality of train running, FTCPN gives the concept of characteristics for tokens based on the features of fuzzy time Petri net. FTCPN was mainly used to analyze the problem of how to avoid train collision in the case of giving priority to train punctuality.