Research On Invulnerability Of Jiangsu Railway And Waterway Freight Transportation Network

Jiangsu’s freight railway network and trunk waterway channel network are important component of the integrated multidimensional transportation network,at the same time,with the vigorous implementation of the "road to railway" and "road to water" for bulk cargo and container transportation,the freight railway network and trunk waterway channel network in Jiangsu Province will play a greater role in the future integrated multidimensional transportation network.However,as an open complex system,they face various uncertain risks in the operation process at all times.Once an emergency occurs,the normal operation of the network will be affected.Therefore,how to improve the network’s resistance to emergencies and ensure the smooth and efficient operation of the network is of great significance.Based on the freight railway network and trunk waterway channel network planned and constructed by Jiangsu Province in 2035,this reasearch firstly constructs the freight railway network model,trunk waterway channel network model and railway-waterway composite freight network model respectively by using the theory of complex network,and analyzes the topological structure characteristics of different networks by calculating the relevant topological structure parameters.The results show that Jiangsu’s freight railway network has scale-free characteristics,but without smallworld characteristics,while trunk waterway channel network and railway-waterway composite freight network don’t have scale-free characteristics and small-world characteristics.Secondly,according to the definition of invulnerability of the studied network,seven node attack strategies and three edge attack strategies are proposed,and the network efficiency,the relative scale of the largest connected subgraph and the number of discrete subgroups are selected as the measurement indicators of network invulnerability,and then the network invulnerability evaluation model is established accordingly.The simulation of all kinds of attack strategies is realized by Matlab software,and the evolution curves of Jangsu’s freight railway network,trunk waterway channel network and railway-waterway composite freight network under different attack strategies and different indestructibility measures are obtained.The reaserch found that the three kinds of network have strong invulnerability to random attack strategy,but weak resistance to intentional attacks.Then,the network efficiency decline rate curve of the three kinds of networks under the same attack strategy is further compared and analyzed,and it is found that the invulnerability of Jiangsu’s freight railway network has the worst invulnerability,the trunk channel network is the strongest,and the railway-waterway composite freight network is in the middle.Finally,the relative change rate of network efficiency is used to measure the impact of single node or single edge failure on network performance,identify the key nodes and critical edges of the railway-waterway composite freight network,and the optimization strategies for network invulnerability are proposed.The conclusions of this dissertation on the invulnerability research of the freight railway network,trunk waterway channel network and railway-waterway composite freight network in Jiangsu Province can help to identify the weak links in the network,help the traffic management department to formulate network protection measures,and improve the network’s ability to resist damage.It also can provide reference suggestions for the integrated multidimensional transportation network planning in Jiangsu Province.