1. Head, Dept. of Agricultural Engineering, Faculty of Agricultural Sciences and Technology, Bahauddin Zakariya Univ., Multan, Pakistan (corresponding author).
2. Professor, Dept. of Civil Engineering, Faculty of Applied Science, 2002 – 6250 Applied Science Lane, Univ. of British Columbia, Vancouver, BC, Canada V6T 1Z4.
3. Research Assistant, Dept. of Civil and Environmental Engineering, Hong Kong Univ. of Science and Technology, Clearwater Bay, Kowloon, Hong Kong, China.