1. Business School of University of Shanghai for Science and Technology, Shanghai, China
2. Department of Civil and Environmental Engineering, Rensselaer Polytechnic Institute, Troy, New York, USA
3. School of Civil and Environmental Engineering, and H. Milton Stewart School of Industrial and Systems Engineering, Georgia Institute of Technology, Atlanta, Georgia, USA
4. Key Laboratory of Road and Traffic Engineering of the Ministry of Education, Tongji University, Shanghai, China