Research On Risk Analysis And Maintenance Strategy Of Railway Emergency Rescue Network Considering Space-time Accessibility

The rational allocation and optimization of railway emergency rescue network are directly related to the efficiency of railway emergency rescue work.However,the railway emergency disposal has the characteristics of strong timeliness,complex and diverse events,and large-scale emergency network,which makes the maintenance and optimization of the entire railway emergency rescue network limited by many factors,such as resource types,personnel distribution,lines,etc.The general description of transport networks in the past may not take into account the specificity of time and space differences in rescue transport,making resource allocation and maintenance enhancement strategies unreasonable.The convenience of using existing rescue stations,transportation networks and other transportation means in railway rescue from emergency rescue resource allocation points to accident occurrence points in the region can be well reflected by space-time accessibility,thus reflecting the comprehensive rescue accessibility of railway emergency network system.Therefore the classical travel time budget model is firstly improved to construct a space-time accessibility model,and the space-time accessibility of resource allocation nodes and edges of the railway emergency rescue network was deeply explored.Then the risk model of the emergency rescue network with accessibility characteristics and the global optimization model of maintenance allocation were constructed to rationalize the maintenance cost of auxiliary emergency rescue departments.It is of great practical significance to maximize railway emergency rescue capability under limited cost.The specific research contents are as follows:Space-time accessibility identification of the railway emergency rescue network: Firstly,the definition and model construction of the railway emergency rescue network are completed.Then,the space-time accessibility identification of emergency resource allocation nodes is identified,and the classical travel time budget model is used to complete the space-time accessibility identification of emergency rescue network resource allocation points considering travel time uncertainty.At the same time,the improved DEMATEL multi-attribute group decision-making evaluation algorithm is used to evaluate the existing capacity of resource allocation points in space-time accessibility identification,revealing the ambiguity of resource allocation capacity and improving the accuracy of space-time accessibility identification results.Finally,combined with the space-time accessibility of resource allocation nodes,the space-time accessibility identification of edges is completed,and the corresponding space-time characteristic parameters of resource allocation nodes and edges are provided.The maintenance risk strategy model of railway emergency rescue network based on space-time accessibility: Firstly,a risk model of railway emergency rescue network considering space-time accessibility is established based on mathematical expectation,combined with the space-time accessibility values of resource allocation nodes and edges in railway emergency rescue network.Secondly,the minimum risk of input failure is taken as the objective of the study,and the objective function of the maintenance allocation strategy model for this railway emergency rescue network is determined in a risk-oriented manner under the constraint of limited total maintenance cost.Finally,the solution method of this maintenance allocation strategy model is determined,and the Lagrangian operator is introduced to complete the analysis of this model to obtain the global optimal solution instead of the local Pareto solution,and compare with other heuristic algorithms and average allocation algorithms.Finally,combined with the actual rescue network data of a railway bureau,this proposed model is solved,and the railway geographic information Arc GIS software is used to realize the visualization of the railway emergency rescue network and its jurisdiction area.Then the space-time accessibility of resource allocation nodes and edges in the emergency rescue network is determined and analyzed.At the same time,the allocation results of maintenance strategies under different inputs are obtained,and the effectiveness and accuracy of the proposed method are analyzed and discussed through comparative experiments.The experimental results show that the proposed method fits the actual characteristics of the resource allocation point of the railway bureau,and the more accurate global optimal solution can be obtained in the allocation process,which can provide some support for the railway emergency management department to formulate the maintenance plan reasonably...