1. Postdoctoral Fellow, Dept. of Building and Real Estate, The Hong Kong Polytechnic Univ., Hung Hom, Kowloon, Hong Kong Special Administrative Region, China (corresponding author).
2. Professor and Associate Head, Dept. of Building and Real Estate, The Hong Kong Polytechnic Univ., Hung Hom, Kowloon, Hong Kong Special Administrative Region, China.