1. Nanjing University,State Key Lab. for Novel Software Technology,P.R. China
2. School of Systems Science, Beijing Normal University,China
3. School of Computer and Electronic Information / School of Artificial Intelligence, Nanjing Normal University,China
4. School of Computer Science and Technology, University of Science and Technology of China,P.R. China
5. Temple University,Center for Networked Computing,USA
6. Samueli School of Engineering, University of California,Computer Science Department,Los Angeles,USA