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991.
Weiping Wang Lixiang Li Haipeng Peng Jinghua Xiao Yixian Yang 《Nonlinear dynamics》2014,76(1):591-598
In this paper, a novel adaptive nonlinear controller is designed to achieve stochastic synchronization of complex networks. We find that this novel adaptive nonlinear controller is less conservative and may be more widely used than the traditional adaptive linear controller. By using the properties of Weiner process, the stochastic synchronization of complex networks with stochastic perturbation via the proposed novel adaptive nonlinear controller can be achieved. Experimental tests demonstrate the superior performance of this novel adaptive nonlinear controller as compared to a conventional adaptive linear controller. 相似文献
992.
The elasto-plastic buckling and postbuckling of fiber metal laminates (FML) are studied in this research. Considering the geometric nonlinearity of the structure and the elasto- plastic deformation of the metal layers, the incremental Von Karman geometric relation of the FML with initial deflection is established. Moreover, an incremental elasto-plastic constitutive relation adopting the mixed hardening rule is introduced to depict the stress-strain relationship of the metal layers. Subsequently, the incremental nonlinear governing equations of the FML subjected to in-plane compressive loads are derived, and the whole problem is solved by the iterative method according to the finite difference method. In numerical examples, the effects of the initial deflection, the loading state, and the geometric parameters on the elasto-plastic buckling and postbuckling of FML are investigated, respectively. 相似文献
993.
994.
According to the digital image encryption, a double encryption algorithm based on the iterative Fourier transform and chaotic transform is proposed. It uses iterative Fourier transform to encrypt image for the first time, then processes the encrypted image through the chaos replacement, which can change image pure phase distribution to realize double encryption. The simulated result shows that the algorithm can effectively resist the attacks of statistical analysis, and has higher encryption effect and safety which is very sensitive to secret key. 相似文献
995.
The pure phase plate was introduced to alter the half-space phase value of the incident linearly polarized hyperolic-cosine-Gaussian (cosh-Gaussian) beams with sine-azimuthal variation wavefront, and focusing properties of the cosh-Gaussian beams by half space phase plate were investigated in detail. Simulation results show that focal pattern can be altered very considerably by the phase plate under condition of different beam parameters, numerical aperture, and phase parameter that indicates the phase change frequency on increasing azimuthal angle. Symmetry of the whole focal pattern can be altered remarkably, polysymmetrical focal patterns evolve into nonsymmetrical focal patterns. And some novel focal shape may appear, including cross-shape, multiple-peak focal pattern, multiple intensity lines, wheel focal pattern, swallowtail focal pattern, and dark hollow focal spots. 相似文献
996.
Lin Zhang 《International Journal of Theoretical Physics》2013,52(6):2112-2117
A simpler approach to the characterization of vanishing conditional mutual information is presented. Some remarks are given as well. More specifically, relating the conditional mutual information to a commutator is a very promising approach towards the approximate version of SSA. That is, it is conjectured that small conditional mutual information implies small perturbation of quantum Markov chain. 相似文献
997.
《European Journal of Operational Research》2005,160(2):353-364
In collaborative e-commerce environments, interoperation is a prerequisite for data warehouses that are physically scattered along the value chain. Adopting system and information quality as success variables, we argue that what is required for data warehouse refreshment in this context is inherently more complex than the materialized view maintenance problem and we offer an approach that addresses refreshment in a federation of data warehouses. Defining a special kind of materialized views, we propose an open multi-agent architecture for their incremental maintenance while considering referential integrity constraints on source data. 相似文献
998.
设H是实Hilber空间, (?)是B(H)中含恒等算子I的算子代数,若(?) 是从(?)到B(H)的线性映射,如果(?)满足对任意的T∈(?),有(?)(T2)=T*(?)(T)+ (?)(T)T-T*(?)(I)T,则称(?)是一个广义Jordan*-左导子;如果(?)满足对任意的T∈(?), 有(?)(T)(ker(T))(?)ran(T*),则称(?)是一个左*-核值保持映射.本文主要获得了如下 结果: Nest代数上每个弱算子拓扑连续的左*-核值保持映射是广义Jordan*-左内 导子,即存在A,B∈B(H),使得对任意的T∈(?),有(?)(T)=T*A+BT.特别地,(?) 也是一个广义Jordan*-左导子. 相似文献
999.
《European Journal of Operational Research》2005,164(1):104-114
By introducing quadratic penalty terms, a convex non-separable quadratic network program can be reduced to an unconstrained optimization problem whose objective function is a piecewise quadratic and continuously differentiable function. A conjugate gradient method is applied to the reduced problem and its convergence is proved. The computation exploits the special network data structures originated from the network simplex method. This algorithmic framework allows direct extension to multicommodity cost flows. Some preliminary computational results are presented. 相似文献
1000.
The incorporation of nanomaterials into electrochemical sensors is an attractive approach towards the improvement of the sensitivity of amperometry and also can provide improved sensor selectivity and stability. This review (with 137 references) details the current state of the art and new trends in nanomaterial-based electrochemical sensing of hydrogen peroxide (H2O2), hydrogen sulfide (H2S) and nitric oxide (NO) in cells or released by cells. The article starts with a discussion of the significance of the three analytes, and this is followed by three sections that summarize the electrochemical detection schemes for H2O2, H2S and NO. Each section first summarizes the respective physiological roles, and then reviews electrochemical sensors based on the use of carbon nanomaterials, noble metal nanomaterials, metal oxide nanomaterials, and layered doubled hydroxides. The materials are compiled in three tables along with figures of merit for the various sensors. 相似文献