Characteristic analysis of basic unit and complex network for urban rail transit

The characteristics of urban rail network were comprehensively studied from part and overall perspectives.From part perspective, the 2-line, 3-line and 4-line basic units of urban rail transit network were analyzed.Indicators such as transfer times, coverage intensity of attraction zone and load of transfer station were proposed to evaluate each basic unit.From overall perspective, complex network theory was used, and in topological Space P, indicators such as the degree, clustering coefficient of node and average path length were proposed to characterize overall network, and network characteristics were understood from topological network.Analysis result shows that the basic units of urban rail transit network are radiation, cross and ring.Triangle with ring, triangle with triangle and multiple triangles are relatively ideal complex forms.In the urban rail network of Beijing, with the increase of node degree, its probability distribution follows the trend of first increasing and then decreasing.The clustering coefficients of many stations are 1, and travels with no more than one time transfer are more than 80%, so the current rail network of Beijing is comparatively convenient.