1. MOE Key Laboratory for Transportation Complex Systems Theory and Technology, School of Traffic and Transportation, Beijing Jiaotong Univ., 100044 Beijing, People’s Republic of China (corresponding author).
2. Professor, Dept. of Transportation Studies, Texas Southern Univ., 3100 Cleburne Ave., Houston, 77004 TX and Yangtzi River Scholar, Beijing Jiaotong Univ., People’s Republic of China.
3. Graduate Research Assistant, Dept. of Transportation Studies, Texas Southern Univ., 3100 Cleburne Ave., Houston, 77004 TX.