Resear ch on Road Network Accessibility Based on Time Impedance Function
基于时间阻抗函数的路网可达性研究

The paper elaborates the accessibility concept and application scope in the different disciplines simply,analyzes the factors influencing accessibility,summarizes quantification method used commonly at the present stage in geometry topology,points out application conditions and insufficiency of the gravity model,the distance model,the accumulation opportunity method.In this foundation,discovers that quantification limiting to the spatial criterion can not respond the relation of the spatial network accurately,in view of this question,proposes the quantification model basing on the time impedance function,which takes the main variable by the practice capacity.This model can respond the spatial demand intensity indirectly.Then the paper introduces the node importance concept,it can reflect factors influencing accessibility in the road network even more directly,such as society,economy,transportation.This model can make up for the insufficiency of space and time method.