Peninsular Provinces Based On Traffic Accessibility Center-Portal System Comparative Analysis

In the context of economic globalization,the economy and society have been updated and integrated,and an economically competitive urban area has been formed.Such basic units are composed of "gateway cities" and the hinterland subordinate to the gateway cities.Both can be regarded as It is a whole,that is,a "city area" with close connections.Based on the "core-edge" of Friedman,this paper builds a comprehensive impact index system for the center and the portal city by means of the GIS platform,and on this basis,the center-portal system of the Shandong Peninsula and the Liaodong Peninsula in 2002 and 2016 The comparative analysis is intended to provide new ideas and scientific basis for China’s urban construction and development.The results show that:(1)The two provinces have basically changed from a "weekend life circle" to a "one-day life circle",and their overall average availability has been reduced from 5.3 hours to 2.8 hours.Among them,the internal accessibility of the two provinces has improved significantly.The spatial pattern of urban internal accessibility presents a "central-peripheral" pattern with provincial capitals as the core and gradually increasing to peripheral areas.The external accessibility pattern shows that the dual-core characteristics of Liaoning Province are becoming more and more solidified.This is because the central city has wider access to the surrounding radiation than the portal city,and Shandong Province,due to the leading role of the portal city,shows a weak dual-core to single The development of nuclear structure.(2)The difference between the two provinces’ central-portal systems is obvious.There are five types of improvement from the hinterland cities to the portal cities,hinterland centers and gateway cities.The increase in the level of portal cities in Shandong Province is stronger than that in the hinterland cities.However,the level of Liaoning Province and the portal city has not changed much.(3)The two provinces’ central-portal system has a positioning order size distribution feature,which is spatially Pareto distribution mode,which shows that the agglomeration effect of the first city is too outstanding,and the upgrowth of tiny and polytechnic town is rather falling.The growth of ostium cities in Shandong Province is faster than that of mean cities,and its center-portal system is shifting towards an open portal.Due to the small gap between the development of the portal and the hinterland cities in Liaoning Province,the dual-core characteristics of the center-portal system are becoming more and more obvious.(4)The indicators of economy and traffic accessibility of the two provinces have a greater impact on the central-portal hierarchy system,and the centrality of the location is less affected.Shandong Province has emerged as a combination of the center and the portal city.