1. Research Fellow, Dept. of Building and Real Estate, The Hong Kong Polytechnic Univ., Hung Hom, Kowloon, Hong Kong ZN703, China (corresponding author).
2. Professor and Interim Dean, Faculty of Construction and Environment, Dept. of Building and Real Estate, The Hong Kong Polytechnic Univ., Hung Hom, Kowloon, Hong Kong ZN738, China.