Invulnerability Research Of China High-Speed Railway Network Based On Complex Network Theory

With the rapid development of China high-speed railway and the continuous improvement of high-speed railway network,high-speed railway plays an increasingly important role in guaranteeing national travel and promoting the steady development of social economy.A stable and reliable high-speed railway network is of great significance to the daily travel and material transportation of Chinese residents.However,due to internal faults or force majeure factors,some of the high-speed railway network lines are interrupted and some stations are suspended from operation,which has different degrees of impact on the service capacity of the China high-speed railway network.In order to ensure the smooth operation of China high-speed railway network and actively deal with the high-speed railway network failure,in this paper,the basic theory and methods of complex network are used to conduct in-depth research on the high-speed railway network invulnerability from various perspectives.Firstly,the structure of China high-speed railway network is analyzed.On this basis,a topological model of China high-speed railway network with 208 nodes and 336 edges is constructed,and the topological properties of the network are analyzed statistically.It is found that China high-speed railway network has neither small-world characteristics nor scale-free characteristics.Then,the definition of invulnerability of China high-speed railway network is put forward.Five invulnerability measures are designed,including the ratio of reachable nodes,aggregation coefficient,network efficiency,average path length,relative size of maximum connected subgraph.Five attack strategies are selected:random attack,initial degree attack,initial betweenness attack,recalculated degree attack and recalculated betweenness attack.On this basis,the evaluation model of China high-speed railway network invulnerability in China is constructed.Next,the invulnerability of China high-speed railway network is simulated by using MATLAB software.The research content includes three aspects.Firstly,with the increasing number of invalid nodes or edges under different attack strategies,the changes of various invulnerability measures of China high-speed railway network are studied.It is found that under random attack strategy,the invulnerability of China high-speed railway network is better.When 30%of the nodes or edges in the network are removed,the invulnerability of the network remains at a high level.The anti-destructive performance of the network is poor.When 10%of the nodes or edges are removed,the anti-destructive performance of the network decreases sharply.Secondly,the influence of single node and edge failure on network invulnerability in China high-speed railway network is studied,and key nodes and edges affecting network invulnerability are found.Thirdly,the simulation evaluation of invulnerability of high-speed railway network under different edge-adding strategies is studied.It is found that the network invulnerability can be effectively improved by adding edges.The edge-adding strategy according to the minimum sum of node degree has the most significant effect on the high-speed railway network invulnerability in China.At last,on the basis of various simulation studies,the measures of high-speed railway network invulnerability optimization in China are put forward from two aspects of existing network protection and optimization of network structure.