1. Associate Professor, Civil Engineering Dept., Univ. of Malaya, 50603 Kuala Lumpur, Malaysia (corresponding author).
2. Senior Lecturer, Civil Engineering Dept., Univ. of Malaya, 50603 Kuala Lumpur, Malaysia.
3. Graduate Student, Mechanical Engineering Dept., Univ. of Malaya, 50603 Kuala Lumpur, Malaysia.
4. Professor, Mechanical Engineering Dept., Univ. Malaysia Pahang, 26300 Kuantan, Malaysia.