Robustness Of Train Operation Plan Adjustment On Railway Passenger Network Under Epidemic

During the COVID-19 epidemic,the Chinese government has adopted a policy of "preventing imports from abroad and preventing rebound from within".In order to reduce the risk of transmission between cities,railway authorities have adopted train operation adjustment programs,such as suspending some trains from severely affected areas and reducing passenger trains from affected areas.Although the spread of the epidemic has been effectively controlled,the structure and connectivity of China’s railway transport network have been greatly affected,and the robustness of the network has been affected.In this paper,we take the railway passenger transportation network in Liaoning Province as an example to study the impact of the adjustment of railway transportation train operation plan on the robustness of railway passenger transportation network under the epidemic.Firstly,the network structure of railway passenger transport network in Liaoning Province is constructed and the network characteristics are analyzed.The Space P and Space L methods are applied to construct the railroad passenger transport service network based on train operation respectively,and the network characteristics such as degree and degree distribution,agglomeration coefficient and average shortest path length are analyzed.Secondly,combing the transport organization policy regulations and train operation adjustment measures on railroad transport organization,two operation scheme adjustment measures of train complete suspensions and train partial suspensions are selected,and the differences in the process of robustness analysis of train operation scheme adjustment under epidemic are determined by comparing the general robustness analysis steps with the regional characteristics of epidemic transport control.Considering regional factors,the node degree value is used as an indicator to determine the regional importance,and then the importance ranking of network station nodes is determined.Finally,the changes of network service level are measured by three indicators: maximum connectivity subgraph,network efficiency,and accessibility,and the robustness of railway passenger transportation network under complete and partial train suspensions are simulated respectively.The robustness of the network is simulated under different scales,the robustness of single city failure,and the robustness of multiple cities failure under complete suspensions,and the robustness of the network is simulated under partial suspensions with different number of stations affected by the epidemic and different train suspensions ratios.The results show that the robustness of the network is better for different regional scales of transport service suspension under complete train suspensions,and the larger the range of scales chosen,the better the robustness of the network.The impact on the network under a single city failure is small,and a certain service level can be restored by adjusting the operation scheme,while the network is less robust under multiple city failures;under partial train suspensions,the maximum connectivity subgraph is less robust under a train suspension ratio greater than 70% or a number of station nodes greater than 10,network efficiency is less robust under a train suspension ratio greater than 30% or a number of station nodes greater than 10,and accessibility is less robust under a train suspension ratio The network performance degrades rapidly when the percentage of train suspensions is greater than 10% or the number of station nodes is greater than 9.By analyzing the robustness of the network for the adjustment of two train operation schemes,complete and partial suspensions,the impact of train stoppage or reduction on the network service level is observed while making transportation adjustment decisions due to controlling the spread of the epidemic.It helps to better coordinate the interrelationship between transportation control and transportation security,and provides a scientific and theoretical basis for railway transport enterprises to make adjustments to train operation plans under epidemic situations.