Abstract
This paper investigates the adaptive dual synchronization of completely different four chaotic and hyperchaotic systems with unknown parameters. Based on the Lyapunov stability theory, an efficient adaptive synchronization controller is constructed that converges the synchronization error signals to the origin with sufficient transient speed. Suitable adaptive laws of unknown parameters are designed that converged the estimated values of the unknown parameters to the true values of the systems parameters. Two numerical examples are presented and simulation results are derived to illustrate the effectiveness of the proposed dual synchronization approach.