Research On The Method Of Urban Agglomeration Hub Planning Based On Analysis Of Supply And Demand Structure

Since the "19th National Congress of the Communist Party of China",promoting the development of urban agglomerations has risen to a national strategic level.As a subsystem of the large social and economic system of urban agglomerations,the modern comprehensive transportation system plays the most important supporting and guaranteeing role in it.With the comprehensive promotion of the strategy of strengthening the country in transportation and the implementation of the comprehensive three-dimensional transportation network planning outline,promoting the construction of national-level urban agglomeration hub clusters has also become the main goal of the current urban agglomeration transportation system development.The internal traffic of urban agglomerations in my country still has problems such as partial imbalance,mismatch of supply and demand,and insufficient coordination between regional local traffic demand and the operation efficiency of the comprehensive transportation system of urban agglomerations.This also shows that although the construction of the main passenger transport hubs of urban agglomerations in my country can meet the needs of the main transportation lines,the radiation depth is not enough,and it lacks the effective support of regional secondary passenger transport hubs.Based on this,this paper proposes a set of optimization methods for the layout of secondary passenger hubs in urban agglomerations.Theoretical research is carried out according to the multi-dimensional system analysis framework of "travel demand orientation-supply structure optimizationnode hub screening-secondary passenger hub layout optimization".First of all,different from the existing research that considers the passenger traffic and sharing rate as indicators of the urban agglomeration travel demand structure from a macro perspective,this paper takes the satisfaction of urban agglomeration travelers with transportation services as the breakthrough point from a micro perspective,and proposes urban agglomeration residents.A method for analyzing the characteristics of travel demand structure.In order to refine the characteristics of travel demand that cannot be represented by explicit variables,this paper fully considers the impact of latent categories and latent variables on the travel demand structure of residents in urban agglomerations,and proposes a model based on LCA(Latent Class Analysis)and PLS-SEM(Partial Least Square method-Structural Equation Modeling)model of multi-group residents’ travel demand structure analysis method.Travelers are classified into four potential categories: "students living in the province","fixed cross-city work","employees living on business trips",and "management business trips",and extracting the travel demand preferences of different potential categories of travelers The difference of the different latent variables and the influence of different latent variables on traveler satisfaction under the condition of multiple latent categories,and then take the Beijing-Tianjin-Hebei urban agglomeration as an example to construct the spatial distribution of the demand structure of the Beijing-Tianjin-Hebei urban agglomeration.Secondly,in view of the problems in traditional clustering methods,such as difficulty in obtaining urban agglomeration county data and inaccurate clustering results,this paper proposes a spatial clustering traffic supply analysis method based on the consideration of urban agglomeration county traffic and socioeconomic characteristics.In this method,a quantification method of urban agglomeration county traffic accessibility based on the shortest path algorithm is proposed,and a regional socioeconomic principal component analysis model of urban agglomeration is constructed,which solves the collinearity problem among multiple socioeconomic influencing factors,and improves the efficiency of urban agglomeration.Accuracy of Spatial Cluster Analysis.Through the implementation and application of various spatial clustering methods,this paper verifies that the SOM(Self-Organizing Mapping)spatial clustering method is more suitable for the problem of supply clustering and grading in urban agglomeration counties.Furthermore,taking the Beijing-Tianjin-Hebei urban agglomeration as an example,it proposes four levels and characteristics that represent the transportation supply capacity,and constructs the spatial distribution of the supply structure of the Beijing-Tianjin-Hebei urban agglomeration in counties.Thirdly,in view of the problem that the existing hub planning methods fail to fully consider the relationship between urban agglomeration regional transportation supply and demand and the relationship between transportation development and social and economic development,this paper regards the mutual feedback effect between transportation infrastructure and regional economic development as a secondary passenger transportation hub.Based on the main basis for selecting points,a method for constructing alternative sets of regional secondary transportation hubs in urban agglomerations based on different supply and demand relationships is proposed.In order to solve the problem of non-stationary characteristics of time series data of regional transportation infrastructure and social and economic development in urban agglomerations,a cross-feedback between transportation infrastructure and regional economic development based on Granger causality test and VAR(Variance Analysis Report)analysis is proposed.The effect analysis method can realize the quantification of the degree of mutual influence between the two in a cycle under the scenarios of "supply level is greater than demand level","supply level is equal to demand level",and "supply level is less than demand level".Finally,in view of the problem of less consideration of the supply and demand structure of urban agglomerations in the existing hub layout optimization methods,this paper proposes a multi-period urban agglomeration secondary passenger transport hub hierarchical layout optimization model based on the feasibility judgment of secondary passenger transport hub candidate points.First,the candidate set optimization based on the mutual feedback effect between transportation infrastructure and regional economic development,and then the "two-stage" hub planning method based on the optimization of the hierarchical layout of secondary passenger transport hubs,realizes the large-scale secondary passenger transport in urban agglomerations.Improved efficiency of hub layout optimization.In order to solve the problem that the value of the mathematical model is too different from the actual situation,fuzzy planning is introduced into the optimization method to fuzzify the passenger travel demand.,which can achieve the development goals and policy orientations of different regions and propose layout optimization results that meet the conditions.