摘要：Orthogonal waveform design is quite an important issue for waveform diversity systems. A chaos based method for the orthogonal discrete frequency coding waveform （DFCW） design is proposed to increase the insufficient orthogonal waveform number and their finite coding length. Premises for chaos choosing and the frequency quantification method are discussed to obtain the best correlation properties. Simulation results show the validity of the theoretic analysis.

摘要：A novel technique for the optimal tuning of power system stabilizer (PSS) was proposed,by integrating the modified particle swarm optimization (MPSO) with the chaos (MPSOC).Firstly,a modification in the particle swarm optimization (PSO) was made by introducing passive congregation (PC).It helps each swarm member in receiving a multitude of information from other members and thus decreases the possibility of a failed attempt at detection or a meaningless ***,the MPSO and chaos were hybridized (MPSOC) to improve the global searching capability and prevent the premature convergence due to local *** robustness of the proposed PSS tuning technique was verified on a multi-machine power system under different operating *** performance of the proposed MPSOC was compared to the MPSO,PSO and GA through eigenvalue analysis,nonlinear time-domain simulation and statistical *** analysis shows acceptable damping of the low-frequency modes and time domain simulations also show that the oscillations of synchronous machines can be rapidly damped for power systems with the proposed *** results show that the presented algorithm has a faster convergence rate with higher degree of accuracy than the GA,PSO and MPSO.

摘要：In this paper, the problems of chaos and chaos control for a class of susceptible-infected- removed （SIR） epidemic model with seasonal fluctuation are investigated. The season- ality in outbreak is natural among infectious diseases, as the common influenza, A type H1N1 influenza and so on. It is shown that there exist chaotic phenomena in the epidemic model. Furthermore, the tracking control method is used to control chaotic motions in the epidemic model. A feedback controller is designed to achieve tracking of an ideal out- put. Thus, the density of infected individuals can converge to zero, in other words, thedisease can be disappeared. Finally, numerical simulations illustrate that the controller is effective.

摘要：To weaken the influence of profile error on compressor aerodynamic performance, especially on pressure ratio and efficiency, a robust design method considering profile error is built to improve the robustness of aerodynamic performance of the blade. The characteristics of profile error are random and small-scaled, which means that to evaluate the influence of profile error on blade aerodynamic performance is a time-intensive and high-precision work. For this reason, non-intrusive polynomial chaos(NIPC) and Kriging surrogate model are introduced in this robust design method to improve the efficiency of uncertainty quantification(UQ) and ensure the evaluate accuracy. The profile error satisfies the Gaussian distribution, and NIPC is carried out to do uncertainty quantification since it has advantages in prediction accuracy and efficiency to get statistical behavior of random profile error. In the integrand points of NIPC, several surrogate models are established based on Latin hypercube sampling(LHS)+ Kriging, which further reduces the costs of optimization design by replacing calling computational fluid dynamic(CFD) repeatedly. The results show that this robust design method can significantly improve the performance robustness in shorter time(40 times faster) without losing accuracy, which is meaningful in engineering application to reduce manufacturing cost in the premise of ensuring the aerodynamic performance. Mechanism analysis of the robustness improvement samples carried out in current work can help find out the key parameter dominating the robustness under the disturbance of profile error, which is meaningful to further improvement of compressor robustness.

摘要：In recent years, the chaos based cryptographic algorithms have suggested some new and efficient ways to develop secure image encryption techniques, but the drawbacks of small key space and weak security in one-dimensional chaotic cryptosystems are obvious. In this paper, permutation and sub- stitution methods are incorporated to present a stronger image encryption algorithm. Spatial chaotic maps are used to realize the position permutation, and to confuse the relationship between the ci- pher-image and the plain-image. The experimental results demonstrate that the suggested encryption scheme of image has the advantages of large key space and high security; moreover, the distribution of grey values of the encrypted image has a random-like behavior.

摘要：A novel active backstepping control method is presented for synchronizing two identical R?ssler hyperchaotic systems with each other and extended to achieve the generalized synchronization of the Chua chaotic system with the R?ssler hyperchaotic system. It is a systematic design approach and consists of a recursive procedure interlacing the choice of a Lyapunov function with the design of active control. In particular, this technique gives flexibility in constructing a control law. Numerical experiments verify the feasibility and effectiveness of the proposed control technique.

摘要：2015年6月24日-26日,由《影视制作》、DV ASIA、北京朝阳规划艺术馆联合主办的"Me Tec 2015影视前沿技术大会"在北京朝阳规划艺术馆召开。作为业界知名的物理渲染与模拟软件公司,鲜少在国内露面的chaos

摘要：In this paper, the Authors present the designing of power system stabilizer (PSS) and static var compensator (SVC) based on chaos, particle swarm optimization (PSO) and shuffled frog leaping (SFL) Algorithms has been presented to improve the power system stability. Single machine infinite bus (SMIB) system with SVC located at the terminal of generator has been considered to evaluate the proposed SVC and PSS controllers. The coefficients of PSS and SVC controller have been optimized by chaos, PSO and SFL algorithms. Fi-nally the system with proposed controllers is simulated for the special disturbance in input power of genera-tor, and then the dynamic responses of generator have been presented. The simulation results show that the system composed with recommended controller has outstanding operation in fast damping of oscillations of power system and describes an application of chaos, PSO and SFL algorithms to the problem of designing a Lead-Lag controller used in PSS and SVC in power system.

摘要：A strategy is proposed to control Lu It is implemented by using sliding mode control system with mismatch uncertainties. The proposed controller ensures the occurrence of the sliding mode motion. It is guaranteed that under the proposed control law, the system state can be regulated to a specific point or in a predictable neighborhood of desired points in the state space even with mismatch uncertainties. Simulation results have illustrated the effectiveness and robustness of the proposed schemes even though the control input is nonlinear.

摘要：Based on the high-dimensional(HD) chaotic maps and the sine function, a new methodology of designing new chaotic maps using dimension expansion is proposed. This method accepts N dimensions of any existing HD chaotic map as inputs to generate new dimensions based on the combined results of those inputs. The main principle of the proposed method is to combine the results of the input dimensions, and then performs a sine-transformation on them to generate new *** characteristics of the generated dimensions are totally different compared to the input dimensions. Thus, both of the generated dimensions and the input dimensions are used to create a new HD chaotic map. An example is illustrated using one of the existing HD chaotic maps. Results show that the generated dimensions have better chaotic performance and higher complexity compared to the input dimensions. Results also show that, in the most cases, the generated dimensions can obtain robust chaos which makes them attractive to usage in a different practical application.