1. Research Assistant, Dept. of Civil and Environmental Engineering, Michigan Technological Univ., 1400 Townsend Dr., Houghton, MI 49931-1295.
2. Associate Professor, Dept. of Civil and Environmental Engineering, Michigan Technological Univ., 1400 Townsend Dr., Houghton, MI 49931-1295 (corresponding author).
3. Professor, School of Civil Engineering and Architecture, Central South Univ., Changsha, Hunan, 410075, China.
4. Postdoctoral Research Associate, Dept.of Physics, Michigan Technological Univ., 1400 Townsend Dr., Houghton, MI 49931-1295.
5. Research Assistant Professor, Dept. of Civil Engineering, Clemson Univ., Clemson, SC 29634.
6. Professor, Department of Physics, Michigan Technological Univ., 1400 Townsend Dr., Houghton, MI 49931-1295.
7. Associate Research Professor, Civil Engineering, Western Transportation Institute, Montana State Univ., Bozeman, MT 59717-4250.