Abstract
We have observed anti-synchronization phenomena in different chaotic dynamical systems. Anti-synchronization can be characterized by the vanishing of the sum of relevant variables. Anti-synchronization problem for different chaotic dynamical systems with fully unknown parameters in response system is analyzed. This technique is applied to achieve anti-synchronization between Lorenz system, Lu system and Four-scroll system. Numerical simulations are provided to verify the effectiveness of the proposed methods. (C) 2009 Elsevier Ltd. All rights reserved.