Study On The Resilience Measurement Of Network Structure Of Cities At Prefecture Level And Above In China

As a strong guarantee to measure the sustainable and stable development of a region,network structure resilience focuses on the influence of the urban network structure on the regional responding to shock and recovery,maintenance or improvement of the original system characteristics and key functions.Meanwhile,it also helps to improve regional stability and is of great significance to the coordinated development of regional space.Starting from the field of resilience,the exploration of regional network structure,on the one hand,is helpful to understand and master the current situation of regional resilience while enriching and developing the resilience theory;on the other hand,it can provide an important reference for regional development planning.Based on Baidu index,Tencent location service and social statistics data,this study took 346 cities at prefecture level and above in China as the research object,and 2017 as the time cut-off point,by calculating the intensity of information flow,population flow,economic connection,and comprehensive connection,the information,traffic,economic and comprehensive connection networks were constructed respectively.With the help of the Geiphi network analysis tool and the ArcGIS spatial analysis software,this study analyzed the topological characteristics of network connection strength,centrality(degree centrality,closeness centrality,betweenness centrality)and network cluster structure.On this basis,from the perspective of resilience,the network structure was measured and evaluated in terms of hierarchy,assortativity,and the interruption scenario transmission and diversity at the regional and individual levels respectively,to put forward strategies and suggestions for the optimization of network structure in the study area.The results were as follows:(1)There are significant differences in information,traffic,economic and comprehensive network among cities at prefecture level and above in China.Although the spatial distribution pattern of each network is "dense in the east and sparse in the west",compared with the traffic connection network,the urban information network has a flatter "diamond" spatial structure,and the information communication between cities is more active,which is less limited by the region and distance,and tends to pay close attention to the developed city or region.The economic connection network is affected by the distance attenuation.The economic elements communication between cities shows a more conservative trend.The ability of cross-regional interaction is weak,and the gap between rich and poor in the east and the west is large.The comprehensive connection network has the most diverse connection paths,with the least difference between the east and the west,and the overall interconnection state is relatively good.(2)The centrality of information,traffic,economic and comprehensive connection network among cities at prefecture level and above in China has significant differences.Cities in the information and economic connection network have a higher centrality,while cities in the traffic and comprehensive connection network have a lower centrality.Cities with higher centrality are mainly distributed in the middle east and coastal areas,and Hu Huanyong line still controls the flow pattern of elements among cities.In the west of the Huhuanyong line,only Lanzhou,Yinchuan,Xining,Hohhot,Lhasa and other provincial capitals have higher centrality.(3)The information,traffic,economic and comprehensive connection network of cities at prefecture level and above in China have different urban cluster structures.The clusters of information,traffic,and comprehensive connection network have relatively complete provincial boundaries.The cluster structure of the information network is characterized by "diverse in the east and single in the west".The traffic network has not formed a large and continuous network cluster structure.In the comprehensive network cluster structure,Hubei and Henan Province show the "lock-in" effect in the province,and the communication with the outside is not obvious.The economic connection network cluster does not have a complete provincial boundary.It has formed a relatively mature economic zone in the Yangtze River Delta and the Pearl River Delta region.The cities are not only closely connected,but also effectively promote the development of the surrounding areas.(4)The hierarchical differences among the information,traffic and economic connection networks of cities at prefecture level and above in China are more significant.The order of hierarchy from strong to weak is economic,information and traffic network.Large cities and provincial capitals with relatively developed economies,rapid information dissemination,and superior traffic location conditions have higher hierarchy in network and are important distribution nodes of resource circulation.Although the economic network structure has the highest hierarchy and the most significant level structure among cities,the over-concentration of "rights" is not conducive to the formation of "robustness" of network structure.(5)The information,traffic and economic networks of cities at prefecture level and above in China are all heterogeneous networks.In information networks,high weighted nodes tend to be connected with low weighted nodes,that is,the network has the highest heterogeneous resilience,followed by traffic and economic networks.Besides,a small number of low weighted nodes in the network have low weighted neighbor nodes,which have a great influence on the circulation and dissemination of elements in the whole network,so the interactive ability between them and high weighted nodes should be strengthened.(6)The results of transmission and diversity resilience of information,traffic and economic networks show that the attenuation of the same city has basically the same impact on network transmission and diversity.From strong to weak,the order of transmission and diversity resilience is information,economic,and traffic network.The cities that have the greatest impact on network transmission and diversity are consistent,with information,traffic,economic and comprehensive connection networks corresponding to Chengdu,Chongqing,Beijing,and Shanghai respectively.There are 12 dominant nodes,all of which are cities with high economic development level and relatively complete comprehensive transportation junction.They play an important regional advantage in resource distribution and allocation and are the key nodes to support the network structure.There are 93 vulnerable nodes in total,mainly some cities far away from the provincial capital or located at the provincial border and minority areas,most of which are "dead corner cities" caused by administrative barriers.