1. National Tsing Hua University,Department of Computer Science,Hsinchu,Taiwan
2. National Chung Cheng University,Department of Computer Science and Information Engineering,Chiayi,Taiwan
3. National Taipei University of Technology,Department of Computer Science and Information Engineering,Taipei,Taiwan
4. Institute of Information Science, Academia Sinica,Taipei,Taiwan
5. National Central University,Department of Computer Science and Information Engineering,Taoyuan,Taiwan