1. Dept. of Construction Management, Harbin Institute of Technology, Harbin, China.
2. Assistant Professor, Dept. of Applied Physics and Electronics, Umeå Univ., Umeå, Sweden (corresponding author).
3. Associate Professor, Dept. of Construction Management, Harbin Institute of Technology, Harbin, China.
4. Professor, Dept. of Applied Physics and Electronics, Umeå Univ., Umeå, Sweden.