1. School of Energy Environment and Materials, King Mongkut’s University of Technology Thonburi, Bangkok 10140, Thailand
2. Faculty of Industrial Education and Technology, King Mongkut’s University of Technology Thonburi, Bangkok 10140, Thailand
3. Department of Electrical Engineering, Dhonburi Rajabhat University Samut-Prakan, Samut-Prakan 10150, Thailand
4. Faculty of Education, University of Miyazaki, Miyazaki 889-2192, Japan