Constructing a family of generalized Lyapunov functions, a new method is proposed to obtain new global attractive set and positive invariant set of the Lorenz chaotic system. The method we proposed greatly simplifies ...Constructing a family of generalized Lyapunov functions, a new method is proposed to obtain new global attractive set and positive invariant set of the Lorenz chaotic system. The method we proposed greatly simplifies the complex proofs of the two famous estimations presented by the Russian scholar Leonov. Our uniform formula can derive a series of the new estimations. Employing the idea of intersection in set theory, we extract a new Leonov formula-like estimation from the family of the estimations. With our method and the new estimation, one can confirm that there are no equilibrium, periodic solutions, almost periodic motions, wandering motions or other chaotic attractors outside the global attractive set. The Lorenz butterfly-like singular attractors are located in the global attractive set only. This result is applied to the chaos control and chaos synchronization. Some feedback control laws are obtained to guarantee that all the trajectories of the Lorenz systems track a periodic solution, or globally stabilize an unstable (or locally stable but not globally asymptotically stable) equilibrium. Further, some new global exponential chaos synchronization results are presented. Our new method and the new results are expected to be applied in real secure communication systems.展开更多
This paper proposes a nonlinear feedback control method to realize global exponential synchronization with channel time-delay between the Lfi system and Chen system, which are regarded as the drive system and the resp...This paper proposes a nonlinear feedback control method to realize global exponential synchronization with channel time-delay between the Lfi system and Chen system, which are regarded as the drive system and the response system respectiveiy. Some effective observers are produced to identify the unknown parameters of the Lii system. Based on the Lyapunov stability theory and linear matrix inequality technique, some sufficient conditions of global exponential synchronization of the two chaotic systems are derived. Simulation results show the effectiveness and feasibility of the proposed controller.展开更多
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.60274007,60474011)the Guangdong Povince Science Foundation for Program of Research Team(Grant No.04205783).
文摘Constructing a family of generalized Lyapunov functions, a new method is proposed to obtain new global attractive set and positive invariant set of the Lorenz chaotic system. The method we proposed greatly simplifies the complex proofs of the two famous estimations presented by the Russian scholar Leonov. Our uniform formula can derive a series of the new estimations. Employing the idea of intersection in set theory, we extract a new Leonov formula-like estimation from the family of the estimations. With our method and the new estimation, one can confirm that there are no equilibrium, periodic solutions, almost periodic motions, wandering motions or other chaotic attractors outside the global attractive set. The Lorenz butterfly-like singular attractors are located in the global attractive set only. This result is applied to the chaos control and chaos synchronization. Some feedback control laws are obtained to guarantee that all the trajectories of the Lorenz systems track a periodic solution, or globally stabilize an unstable (or locally stable but not globally asymptotically stable) equilibrium. Further, some new global exponential chaos synchronization results are presented. Our new method and the new results are expected to be applied in real secure communication systems.
基金Project supported by the Fundamental Research Funds for the Central Universities (Grant No. CDJZR10 17 00 02)
文摘This paper proposes a nonlinear feedback control method to realize global exponential synchronization with channel time-delay between the Lfi system and Chen system, which are regarded as the drive system and the response system respectiveiy. Some effective observers are produced to identify the unknown parameters of the Lii system. Based on the Lyapunov stability theory and linear matrix inequality technique, some sufficient conditions of global exponential synchronization of the two chaotic systems are derived. Simulation results show the effectiveness and feasibility of the proposed controller.
