| With the vigorous development of China’s rail transit industry,the rail transit network in various places has been gradually improved,and rail transit has entered a new situation of networked operation.After the emergence of the new crown epidemic,rail transit is now facing more severe challenges,and the reliability of rail transit networks has also ushered in a greater test.Therefore,how to effectively identify the weak points and risk points in the rail transit network,so as to strengthen the security protection,improve the reliability of the rail transit network under the background of the normalization of the epidemic,and reduce the operational risk,has become the focus of the current urban rail transit operation management.First of all,this paper analyzes the passenger flow characteristics of Beijing’s rail transit network during the COVID-19 epidemic,summarizes the passenger flow trend from the three levels of line network,line and station,and summarizes the passenger flow characteristics of the urban rail transit network under the epidemic.Secondly,according to the basic theory of urban rail transit complex network,the Space L method is used to construct the unweighted topology network model and weighted topology network model of Beijing rail transit,and the complex characteristics of the two networks are statistically analyzed.The average path length of the transportation network is large,and the network clustering coefficient is small,showing obvious scale-free characteristics.Then,an improved Page Rank algorithm is proposed and applied to the weighted network of Beijing’s rail transit,to identify important stations in Beijing’s rail transit network during the COVID-19 epidemic,and through analysis,it is found that the node PR value and node strength have a relatively obvious positive correlation,and the algorithm is more reasonable for important node identification.Finally,the concept of urban rail transit network reliability under the epidemic is proposed,and the global network efficiency,the relative size of the largest connected subgraph and the transportation volume ratio are used as network reliability measurement indicators,and the reliability of Beijing’s rail transit network under the epidemic is obtained through simulation.The change trend of the measurement index.The simulation results show that random attacks have little impact on the reliability of urban rail transit networks,but will be severely damaged in a short period of time under deliberate attacks,indicating that important stations in the network have a greater impact on reliability.In addition,the simulation in this paper also verifies that using PR value to evaluate the importance of nodes has good accuracy,which can provide theoretical support for the evaluation of node importance in the network,and has certain practical value and practical significance. |
