Research on the Complex Characteristics of Urban Subway Network and the Identification Method of Key Lines

Based on the complex network theory, we established a topological of Beijing subway under Space L, P, and C. Then, analyzed characteristics each network, proposed global impact indexes (including aggregation coefficient, path length efficiency connectivity coefficient), interline degree centrality near-centrality coefficient intermediate higher value, more obvious effect other lines; sensitivity vulnerable to lines). At local levels, it is possible analyze different lines situation lines. The concept “line importance index” identify key in network. characterized by scale-free small-world but no L Subway Line 10, 9, 1, 2, 5 are five with highest importance. S1, Changping Line, Xijiao Capital Airport Daxing International lowest