1. Department of Electrical Engineering; Nation Center University; Jhongli 32001 Taiwan, R.O.C
2. Department of Mechatronic Technology; National Taiwan Normal University; Taipei 10610 Taiwan, R.O.C
3. Department of Electronic Engineering; Chang-Gung University; Taoyuna 333 Taiwan, R.O.C
4. Green technology Research center, Chang-Gung University; Taoyuna 333 Tawin, R.O.C