Phongsatorn Chanpen School of Engineering and Technology, Walailak University, Nakhon Si Thammarat Thailand
Thanongsak Imjai School of Engineering and Technology, Walailak University, Nakhon Si Thammarat Thailand
Surin Sutthiprabha Department of Civil Engineering, Rajamangala University of Technology Tawan-Ok, Bangkok, Uthenthawai Campus Thailand