Study the Spatial Influence of Urban Economic in ChongQing
利用空间相互作用引力模型分析重庆市的经济影响力，通过与周边中心城市对比，将区域划分为四个引力影响等级，为重庆主体功能区划提供参考。
Using the gravity model of the spatial interaction that analysing the urban economic impact-force of Chongqing.Based on the contrast of attractive force between Chongqing and its neighboring central city(Chengdu,Xi'an,Wuhan,Changsha,Guiyang and Kunming),we can divide the region into four different parts,namely : The first part which Chongqing gravity is greater than the sum of the other cities in the region,is named strong gravitational influence zone;The second part which Chongqing gravity is greater than maximum gravity-affected of the other cities in the region,is named secondary strong zone;The third part which is greater than the average of other cities in the region,is named moderate gravity-affected zone;And the fourth part which smaller than the average of other cities in the region,is the weak gravitational influence zone.The results show that: the strong economic impact zone has been expanded to Sichuan and Guizhou provinces;a high gravitational influence value belt is formed between Chengdu,Chongqing and Guiyang,for their influence have penetrated through the breaking point into each other zone;the gravitational break points between Chongqing and the other ceties(Kunming,Xi'an,Changsha,Wuhan) are located in the border areas of the four provinces,these areas are usually away over 200-300km from the provincial capital city.Dividing the Gravitational strength grade of the region can be referenced by the Major Function Oriented Zoning in Chongqing.