1. Associate Professor, Dept. of Building, National Univ. of Singapore, 4 Architecture Dr., Singapore 117566.
2. Lecturer, School of Engineering and Technology, Central Queensland Univ., 400 Kent St., Sydney, NSW 2000, Australia (corresponding author).
3. Facilities Administrator, NetApp Singapore Pte Ltd, Millenia Tower, 1 Temasek Ave., Singapore 039192.