1. Ph.D. Student, School of Transportation and Logistics, Dalian Univ. of Technology, No. 2, Linggong Rd., Ganjingzi District, Dalian 116023, China.
2. Professor, School of Transportation and Logistics, Dalian Univ. of Technology, No. 2, Linggong Rd., Ganjingzi District, Dalian 116023, China (corresponding author).