1. Department of Optoelectronics and Materials Engineering, Chung Hua University, Hsinchu 30012, Taiwan, R.O.C
2. Institute of Electronics Engineering, National Chiao Tung University, Hsinchu 30010, Taiwan, R.O.C
3. College of Electrical and Computing Engineering, National Chiao Tung University, Hsinchu 30010, Taiwan, R.O.C
4. Department of Business Administration, National Central University, Taoyuan 32001, Taiwan, R.O.C