1. Ph.D. Candidate, School of Control Science and Engineering, Public Transit Planning, Shandong Univ., 17923 Jingshi Rd., Jinan, Shandong 250061, China.
2. Associate Professor, School of Control Science and Engineering, Public Transit Planning, Shandong Univ., 17923 Jingshi Rd., Jinan, Shandong 250061, China (corresponding author).
3. Ph.D. Candidate, Dept. of Civil and Environmental Engineering, Univ. of Maryland, College Park, MD 20742.
4. Associate Professor, Dept. of Civil Engineering, Univ. of Wisconsin at Milwaukee, Milwaukee, WI 53201.
5. Professor, School of Control Science and Engineering, Shandong Univ., 17923 Jingshi Rd., Jinan, Shandong 250061, China.