1. Professor, School of Traffic and Transportation Engineering, Changsha Univ. of Science and Technology, Changsha 410114, China.
2. M.S. Student, School of Traffic and Transportation Engineering, Changsha Univ. of Science and Technology, Changsha 410114, China (corresponding author).
3. M.S. Student, Hunan Huida Planning, Survey and Design Research Co., Ltd., No. 31, Xiangfu West Rd., Tianxin District, Changsha 410114, China.
4. M.S. Student, School of Traffic and Transportation Engineering, Changsha Univ. of Science and Technology, Changsha 410114, China.