Study On The Location Of Emergency Resources Based On The Key Nodes In The Road Network

Road network as a whole,in practice,the generations of congestion in the network are not no rules to follow,it mainly by a certain intersection congestion that caused a range of road network paralysis.As the traffic jams caused by the traffic accidents and other emergency situations occur frequently,so,after the size of the road network has been basically determined,through the analysis of the topology of road network to identify the key nodes supporting road network,and the establishment of the emergency resource allocations to protect the nodes to avoid the complete collapse of road network,is a simple and effective way to improve the efficiency of urban road network operation.Based on the analyses and summarizations of the evaluation methods of key nodes, this paper pointed out the shortcomings of the existing evaluation methods,that is unable to use a single evaluation index to evaluate the importance of nodes. In order to evaluate the importance of nodes better,it needs to evaluate each indexes of the nodes comprehensively.On the basis of the research on the theories and clustering principles of the self-organization competitive neural network,this paper established the key nodes’ identification model based on the self-organizing competitive neural network,to make comprehensive evaluation on the importance of the nodes based on characteristic indexes.This paper studied the113nodes of the area network within the Second Ring Road in Beijing,using the node weighted degree,betweenness,load degree as the evaluation indexes,as the input of the identification model,through clustering arithmetic,the113nodes were divided into6classes,and according to the average characteristic parameters of each class,then the6classes were divided into4key levels. Trough comparing with the nodes’ actual situations,it illustrated the key nodes of self-organizing competitive neural network identification model was feasible.Then,on the basis of summarizing the solving methods of emergency resource location problems,and based on p-center problem,this paper established the emergency resource location model,and designed the model algorithm based on the genetic algorithm.This paper chose the first level key nodes as the research object,then established emergency resource location model in the area network within the Second Ring Road in Beijing,and usd MATLAB genetic algorithm toolbox to solve the model, finally arrived at the specific locations of the emergency resource allocations in the area network within the Second Ring Road in Beijing.The results showed that when the road network produced the emergency demand points,emergency resource allocation points could provide emergency services in the shortest possible time to prevent the congestion diffusion effectively and avoid total paralysis of the road network.