1. Ph.D. Student, Dept. of Civil Engineering, Institute of Transportation Research, Monash Univ., Victoria 3800, Australia (corresponding author). E-mail: ruimin.li@eng.monash.edu.au
2. Associate Professor, Dept. of Civil Engineering, Institute of Transportation Research, Monash Univ., Victoria 3800, Australia. E-mail: geoff.rose@eng.monash.edu.au
3. Lecturer, Dept. of Civil Engineering, Institute of Transportation Research, Monash Univ., Victoria 3800, Australia. E-mail: majid.sarvi@eng.monash.edu.au