1. Department of Electro-Optical Engineering, National United University, No. 2 Lienda, Miaoli 36063, Taiwan
2. Department of Electrical Engineering, Yuan Ze University, 135, Yuan-Tung Road, Chung-Li 32003, Taiwan
3. Department of Mechanical and Electromechanical Engineering, Tamkang University, New Taipei 25137, Taiwan
4. Department of Mechanical Engineering, National Chung Hsing University, Taichung 402, Taiwan