1. Ph.D. Candidate, School of Transportation and Logistics, Southwest Jiaotong Univ., 111 the Second Ring Rd. North, Chengdu, Sichuan 610031, China.
2. Associate Professor, Ingram School of Engineering, Texas State Univ., San Marcos, TX 78666 (corresponding author).
3. Research Associate, Institute for Multimodal Transportation, Jackson State Univ., 1230 Raymond Rd. 900, Jackson, MS 39204.
4. Professor, School of Transportation and Logistics, Southwest Jiaotong Univ., 111 the Second Ring Rd. North, Chengdu, Sichuan 610031, China.