1. Ph.D. Student, School of Vehicle and Mobility, Tsinghua Univ., Beijing 100084, China.
2. Graduate Student, School of Information Engineering, Chang’an Univ., Xi’an 710064, China.
3. Assistant Researcher, School of Civil Engineering, Tsinghua Univ., Beijing 100084, China (corresponding author).
4. Marie Curie Fellow, Dept. of Architecture and Civil Engineering, Chalmers Univ. of Technology, Gothenburg SE-41296, Sweden.