Research On The Topology Structure Of Highway Network In China

Since the reform and opening up,the mileage of highways in China has grown significantly,gradually becoming networked and scaled.However,due to the influence of economy,policy and geographical environment,the complexity of its network structure has become increasingly apparent in the process of rapid development of highways.Insufficient cognition of the highway network structure may lead to unbalanced highway development,which is not conducive to the improvement and performance of the overall network performance.Therefore,this study analyzes the development law of highway network from the perspective of evolution,aiming at clarifying the "trend" problem of the structure of the highway network evolution,planning the construction by means of regulation,realizing the orderly and efficient development of the highway network,and then improving the overall benefits.First,the highway evolution model is measured.the node connection patterns and the connection preferences are clarified.Based on the highway connectivity data between cities in China from 1990 to 2016,the L-space mapping method is adopted.Taking 318 cities in China as the nodes and highways as the inter-city connection lines,the highway topology map of China based on time series is constructed.This paper analyzes the evolution model of expressway network.The analysis of the highway network evolution model shows that,after 2003,China's highway network is characterized by “small world” and the addition of “shortcut” and the connection of “sub-picture” in the network greatly improve the network performance;from 1990 to 2004,there was a preference for preferential connections in the new nodes;after 2004,this connection preference gradually weakened and fluctuated after 2011.Second,the highway network structure and node evolution characteristics are analyzed.The evolution of China's highway network is visualized.Based on the parameters of complex network indicators,the mean value,degree variance,network aggregation coefficient and network global efficiency are used to analyze the evolution characteristics of highway network structure in China and the intermediate degree and closeness degree are selected to analyze the evolution characteristics of highway network nodes in China.According to the connection mode and preference of nodes in the above network,the network shape evolution and network structure index characteristics are explained,the reasons are analyzed,and the suggestions for improving the overall efficiency of the network are proposed.The top ten cities in the annual ranking are summarized based on the node indicators.According to the relationship between the evolution of node indicators and the city,whether the “structural status” and “functional status” of the city are consistent with each other is analyzed,so as to propose relevant suggestions that can give play to the advantage of location and promote the maximization of network benefits.Finally,the relationship between network density and regional attributes and node metrics is analyzed.According to the evolution law of nodes,the assumption that the node indicators are related to network density and regional attributes is proposed.China is divided into seven regions of East China,South China,Central China,North China,Northwest China,Southwest China and Northeast China and the differences of node indicators in different regions are compared and sorted.According to the analysis results,suggestions for improvement are proposed for specific regions.Combining the complex network theory,this paper analyzes the topology structure of China's expressway network from the perspective of evolution,and studies the connection mechanism of nodes,the evolution of network morphology,the evolution of network structure,the evolution of network nodes and regional differences.This paper can improve the general understanding of the evolution characteristics and laws of highway networks in China,and has certain practical significance for guiding the planning and connection of highways between cities.