2STEPHEN J K, ROBERT G S. An Analysis of Inter- change Operation in an Urban Automated Highway Net- work[J]. Transportation Research, 1972, 6 (4): 381-101.
3MICHEL V A, SAM Y. Volume Effects on Speeds of 2- lane Highways in Ontario[J]o Transportation Research Part A, 1983,17(4) :301-313.
4SANDEEP D, SATISH S. Impact of Cold and Snow on Temporal and Spatial Variations of Highway Traffic Vol- umes[J]. Journal of Transport Geography, 2008,16 (5) : 358-372.
5ESMAEEL A, EHSAN A. Investigation on the Role of Traffic Volume in Accidents on Urban Highways[J]o Journal of Safety Research, 2011,42(3):209-214.