The Journal of King Mongkut's University of Technology North Bangkok
วารสารวิชาการพระจอมเกล้าพระนครเหนือ

Jirapol Pinthong
Department of Teacher Training in Electrical Engineering, Faculty of Technical Education, King Mongkut’ s University of Technology North Bangkok, Bangkok
Thailand

Wattana Kaewmanee
Department of Teacher Training in Electrical Engineering, Faculty of Technical Education, King Mongkut’ s University of Technology North Bangkok, Bangkok
Thailand