Research On Evolution Model Of Metro-bus Coupling Network And Application

With the rapid development of urban rail transit,more and more cities have gradually formed a multi-mode public transportation system with conventional public transportation and subway as the main body,which undoubtedly increases the complexity of public transit network planning.In order to restore the generation of real public transportation network and reduce the cost of public transportation network planning,this paper aims at the coupling relationship between the two public transportation networks,uses complex network theory to mine the bus network data of five cities,and combined with the urban road network,makes an exploratory study on the evolution of public transport network in urban space.Firstly,based on the coupling relationship between the conventional transit network and the metro network,the topology model of the basic-core public transportation network is established;using the model to establish the topology network of Beijing public transport,comparing and analyzing the degree distribution,average path length,clustering coefficient and other basic topological characteristics of Beijing transit coupling network and its sub networks in SPACE-L and SPACE-P,and it is found that the basic characteristics of coupling network are determined by the basic network,but the embedding of metro network can improve the service quality of the whole public transport system,so the advantages of metro-bus coupling network are verified.Then,in order to study the evolution characteristics of coupling network,this paper selects five urban transit networks with different scales but the same network structure to take empirical research.By comparing the topological evolution and spatial layout evolution indicators including network density,cumulative degree distribution,average degree of neighbor nodes of five transit networks,the generation cycle of transit network is found,and the evolution characteristic parameters of different scale networks are determined.With the further study,obtaining the coupling characteristics of the metro network and the conventional transit network,the spatial layout characteristics of the initial and terminal stations and transfer stations of the metro network,which fills the blank of the existing research on the evolution of the metro network.It is found that the stations in the initial stage of the metro network tend to be generated in the urban space with high coupling strength,and with the increase of the network scale,the generation and connection of metro stations gradually presents randomness.Next,in order to restore the generation of the real network in urban space,aiming at the shortcomings of the existing evolution model,based on the obtained evolution rules and evolution characteristic parameters of the transit coupling network,this paper constructs a two-stage evolution model of the metro-bus coupling network with using the urban road network data to embed spatial information for the evolving transit stations.The model restores the basic shape of Shijiazhuang public transit network,and the distribution of each evaluation indicator is consistent with the real network,which verifies the feasibility and practical significance of the model.Finally,in order to evaluate the importance of stops more accurately,two new evaluation indicators,congestion degree and coupling degree,are proposed and use them to find the key stops of Shijiazhuang original network and model prediction network.The importance level distribution map of bus stops is drawn,which can locate the key stops and potential congested sections in city to provides decision-making guidance for the planning and operation of urban transit network.