Junling LI received his Masters degree from Qufu Normal University in 2006, and now he is an assis- tant at the same university. His research interests include adaptive control and hybrid dynamic sys- tems. E-mail: ljltongzhi@ 163.com. Xuejun XIE received his Ph.D degree from the Institute of Systems Science, Chinese Academy of Sciences in 1999. From March 2001 to March 2003, he did postdoctoral research at Northeastern University. He is now a professor of Qufu Normal University and Xuzhou Normal University. His research interests include adaptive control for com- plex systems. Corresponding author of this paper. E-mail: xxj @mail.qfnu.edu.cn. Wei CHEN is a master candidate in Qufu Normal University, her research interests in adaptive control. E-mail: chchenwei2006@ 163.com.