1. Department of Electronic Engineering, Ming Chi University of Technology, New Taipei City, Taiwan, ROC
2. Department of Computer Science, University of Taipei, Taipei City, Taiwan, ROC
3. Department of Information Management, Chaoyang University of Technology, Taichung City, Taiwan, ROC
4. Department of Computer Science and Information Engineering, National Taipei University, National Taipei University, New Taipei City, Taiwan, ROC