1. Department of Electronic Engineering, Chienkuo Technology University, Changhua City, Taiwan, Republic of China
2. Department of Industrial Education and Technology, National Changhua University of Education, Changhua City, Taiwan, Republic of China
3. Institute of Mechatronoptic Systems, Chienkuo Technology University, Changhua City, Taiwan, Republic of China
4. Department of Electrical Engineering, Kao Yuan University, Kaohsiung, Taiwan, Republic of China