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991.
992.
993.
利用Manasevich-Mawhin延拓定理和一些分析技巧,建立了一类具多个偏差变元Rayleigh型p-Laplacian方程周期解存在的充分性条件,是已有结果的一个补充. 相似文献
994.
The asymptotic behavior of periodic solutions to fractal nonlinear Burgers equation is considered and the initial data are allowed to be arbitrarily large.The exponential decay estimates of the solutio... 相似文献
995.
996.
An important tool for the construction of periodic wavelet frame with the help of extension principles was presented in the Fourier domain by Zhang and Saito [Appl. Comput. Harmon. Anal., 2008, 125: 68-186]. We extend their results to the dilation matrix cases in two aspects. We first show that the periodization of any wavelet frame constructed by the unitary extension principle formulated by Ron and Shen is still a periodic wavelet frame under weaker conditions than that given by Zhang and Saito, and then prove that the periodization of those generated by the mixed extension principle is also a periodic wavelet frame if the scaling functions have compact supports. 相似文献
997.
在研究两斑块间具有非对称脉冲扩散的带时滞的捕食食饵系统的问题中,利用脉冲微分方程的比较原理和一些分析技巧,得到了捕食者灭绝的正周期解全局吸引性的充分条件,建立了系统的持久性. 相似文献
998.
N. Cavalagli F. Cluni V. Gusella 《International Journal of Solids and Structures》2013,50(25-26):4226-4240
The paper presents a method to estimate the Statistically Equivalent Periodic Unit Cell (SEPUC) corresponding to a masonry with quasi-periodic texture. The identification of the texture and the constituent phases (unit blocks and mortar joints) is achieved by means of digital image processing techniques applied to color image of the masonry wall. A statistical analysis of geometrical parameters (width and height of blocks, thickness and length of mortar joints) allows to estimate their probability distribution and to identify the typology of the texture. Subsequently a Monte Carlo analysis is performed using several tentative SEPUCs generated with different dimensions of blocks and joints according to the estimated distributions. A criterion was eventually proposed to identify, among the numerically generated ones, the SEPUC which is more suitable to model the behavior of masonry wall. The SEPUC is analyzed with techniques available for periodic texture, applying periodic boundary conditions, in order to estimate the equivalent elastic stiffness. The proposed method is validated comparing the results in the elastic range obtained with SEPUC and those obtained imposing essential and natural boundary conditions on the original texture. 相似文献
999.
In the present paper,a general solution involving three arbitrary functions for the generalized(2+1)dimensional KdV-mKdV equation,which is derived fromthe generalized(1+1)-dimensional KdV-mKdV equation,is first introduced by means of the Wiess,Tabor,Carnevale(WTC) truncation method.And then multisymplectic formulations with several conservation lawstaken into account are presented for the generalized(2+1)dimensional KdV-mKdV equation based on the multisymplectic theory of Bridges.Subsequently,in order tosimulate the periodic wave solutions in terms of rationalfunctions of the Jacobi elliptic functions derived from thegeneral solution,a semi-implicit multi-symplectic schemeis constructed that is equivalent to the Preissmann scheme.From the results of the numerical experiments,we can conclude that the multi-symplectic schemes can accurately simulate the periodic wave solutions of the generalized(2+1)dimensional KdV-mKdV equation while preserve approximately the conservation laws. 相似文献
1000.
混沌系统的递次错位反馈控制方法研究 总被引:7,自引:3,他引:4
设计了一种递次错位反馈控制(SDF)方法来实现混沌控制.介绍了SDF方法的控制原理,以单模激光Lorenz混沌系统作为典型的例子,验证了这种控制方法的有效性.比较单模激光Lorenz混沌系统受控前后相图、功率谱和相空间重构等刻划混沌系统的特征量.数值模拟结果显示, 受控系统的相图和相空间重构中由具有无穷嵌套自相似结构并限定在有限相空间内的混沌吸引子转变为周期数为2n×3mp(n、m为整数)的周期轨道;同时,功率谱也由连续谱转变为具有独立单峰的分立谱. 相似文献