1. Department of Electrical and Electronic Engineering, Faculty of Engineering, Universiti Putra Malaysia (UPM), 43400 Serdang, Selangor, Malaysia
2. Institute of Advanced Technology (ITMA), Universiti Putra Malaysia (UPM), 43400 Serdang, Selangor, Malaysia
3. Department of Brain Science and Engineering, Kyushu Institute of Technology, Fukuoka Prefecture, 808-0196, Japan