2Pattara-atikom W, Ponqpaibool P. Thaichayaponq S. Estimatingroad traffic congestion using vehicle velocity[C], chengdu : UESTC (电子科大): International Conference on ITS Telecommunications, 2006: 1001-1004.
3Ren Qiliang. Research on H-fuzzy evaluation method for traffic congestion of city road-network[J]. In- formation Management, Innovation Management and Industrial Engineering, 2008 ( 3 ) : 41-44.