Corresponding author.Weisheng Chen was born in 1977. He received his B.S. degree in the Department of Mathemat- ics from Qufu Normal University, Qufu, China, in 2000, M.S. and Ph.D. degrees in the Depart- ment of Applied Mathematics from Xidian Uni- versity, Xi'an, China, in 2004 and 2007, respec- tively. He has authored or coauthored more than 30 journal and conference oublications. His re-search interests include adaptive control, learning control, neural network control and so on. E-mail:wshchen@ 126.com Ruihong Li was born in 1980. She received her B.S. degree in the Department of Applied Math- ematics from Xidian University, Xi'an, China, in 2003, M.S. and Ph.D. degrees in the Depart- ment of Applied Mathematics from Northwestern Polytechnical University, Xi'an, China, in 2005 and 2008, respectively. Her research interest in- cludes chaos synchronization.