Research On Topological Structure Characteristics And Robustness Of Urban Public Transport Network Space

Public transportation is an important travel mode for residents,and with its advantages of strong transportation capacity,high transportation efficiency,and low operating energy consumption,it has become an important means to alleviate urban traffic pressure.At present,major cities have vigorously developed the construction of urban public transport networks,and have generally formed a relatively mature urban conventional bus network.The construction of urban rail transit networks is also taking shape.Based on the key project of the National Natural Science Foundation of China,"Theory and Method for Collaborative Planning of Urban Multimodal Transport Networks Based on Generalized Transport Hubs"(Project Approval No.51638004),this paper conducts research on the spatial topological structure characteristics and robustness of urban public transport networks by introducing complex network theory and based on urban conventional trunk bus and rail transit networks,Provide theoretical reference for urban public transportation construction and operation management,and promote the full play of the coupling efficiency of urban public transportation system.Considering a more accurate abstract representation of the urban public transport network,a topological network model of the urban public transport subnetworks Space L_p and Space L_lis proposed,and a construction method of the urban public transport coupling topological network based on conventional trunk bus and rail transit is given,laying a methodological and theoretical foundation for constructing the urban public transport topological network model.Introduce the collection and preprocessing process of urban public transport network GIS data and swiping card data,and select Harbin regular trunk bus network and rail transit network as examples to obtain and preprocess the data;Under the guidance of the network topology modeling method in Chapter 2,the model is constructed,and random shortest path acquisition is performed on the constructed topology network to verify the connectivity and accuracy of the constructed network model;At the same time,complete the data matching between the card reading data and the topological network model,providing a network model and data foundation for Chapter 4 to explore the characteristics of the topological structure of the network space.Propose indicators for the spatial distribution characteristics of urban public transport networks,and construct an indicator system for the spatial topological structure characteristics of urban public transport networks.Using the Shannon entropy of road network orientation for reference,urban public transport routes and network orientation entropy are proposed to measure the spatial orientation distribution of urban public transport networks.At the same time,the indicators selected in the current specifications that can reflect the spatial distribution pattern of the network and the bus network orientation entropy together constitute the spatial distribution characteristic indicators of urban public transport networks;The topological structure characteristic index of public transport network is composed of basic static geometric characteristic indexes in complex network theory.Taking the public transport network in Harbin as an example,research was conducted on the spatial orientation distribution and topological structure characteristics of the network,exploring the correlation between subnetworks and coupling networks.Explain the connotation of the robustness of urban public transport networks,and select indicators for measuring the robustness of urban public transport networks;The attack test is introduced as an analysis method for network robustness.The attack modes are divided into random attacks and deliberate attacks based on the ranking of node degree centrality,intermediate number centrality,proximity degree centrality,and core number.The attack object is divided into initial network and dynamic network according to network mode,and a program is written using Python language to analyze the changes in robustness indicators of Harbin public transport subnetwork and coupling network under network attack.The research shows that the initial network of Harbin rail transit is very sensitive to random attacks by nodes,while the intentional attacks launched according to the size of node proximity in dynamic network mode are more destructive to the network;For the public transport coupling network in Harbin,the conventional trunk bus network contributes more than 98%of the nodes and connections.The variation trend of the robustness indicators of the coupling network and the conventional trunk bus network is similar.When faced with deliberate attacks under dynamic networks,the robustness of the coupling network and the conventional trunk bus network is weak.