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排序方式: 共有203条查询结果,搜索用时 15 毫秒
171.
Two kinds of iterative methods are designed to solve the linear system of equations, we obtain a new interpretation in terms of a geometric concept. Therefore, we have a better insight into the essence of the iterative methods and provide a reference for further study and design. Finally, a new iterative method is designed named as the diverse relaxation parameter of the SOR method which, in particular, demonstrates the geometric characteristics. Many examples prove that the method is quite effective. 相似文献
172.
In this paper, we develop an efficient approach to compute the equivariant normal form of delay differential equations with
parameters in the presence of symmetry. We present and justify a process that involves center manifold reduction and normalization
preserving the symmetry, and that yields normal forms explicitly in terms of the coefficients of the original system. We observe
that the form of the reduced vector field relies only on the information of the linearized system at the critical point and
on the inherent symmetry, and the normal forms give critical information about not only the existence but also the stability
and direction of bifurcated spatiotemporal patterns. We illustrate our general results by some applications to fold bifurcation,
equivariant Hopf bifurcation and Hopf-Hopf interaction, with a detailed case study of additive neurons with delayed feedback. 相似文献
173.
174.
The generalized successive overrelaxation (GSOR) method was presented and studied by Bai, Parlett and Wang [Numer. Math. 102(2005), pp.1-38] for solving the augmented system of linear equations, and the optimal iteration parameters and the corresponding optimal convergence factor were exactly obtained. In this paper, we further estimate the contraction and the semi-contraction factors of the GSOR method. The motivation of the study is that the convergence speed of an iteration method is actually decided by the contraction factor but not by the spectral radius in finite-step iteration computations. For the nonsingular augmented linear system, under some restrictions we obtain the contraction domain of the parameters involved, which guarantees that the contraction factor of the GSOR method is less than one. For the singular but consistent augmented linear system, we also obtain the semi-contraction domain of the parameters in a similar fashion. Finally, we use two numerical examples to verify the theoretical results and the effectiveness of the GSOR method. 相似文献
175.
量测方程中含有未知参向量的线性离散时间系统的最优控制 总被引:1,自引:0,他引:1
对于线性离散时间系统的最优控制问题已经有了很好的结果,在其中它们的状态方程与量测方程中是不含未知参向量的。然而在实际问题中有这样一种情况,量测方程中含有未知参向量。比如在研究一河流某处“来水予报”的数学模型时,就遇到建立含有参向量的随机系统模型,k时刻的来水量(系统k时刻的状态Xk),不仅依赖于k-1时刻的来水量(系统k-1时刻的状态Xk-1),而且还依赖于其它的因素(降雨量、蒸发量、积雪深度…… 相似文献
176.
姜立新 《非线性动力学学报》1995,2(2):158-167
本文根据平均法的思想,用精确积分的方法得到分岔方程,然后用奇异性理论研究了主共振情况下的分岔性态。在正阻尼的情况下得到了九种分岔模式,本文的分析方法具有一定的理论意义,拨是结果对改善和设计具有良好动力学性能的分段线性机械系统提供了理论依据。 相似文献
177.
Cheng Ouyang 《分析论及其应用》2005,21(4):311-316
A class of semi-linear Robin problem is considered. Under appropriate assumptions, the existence and asymptotic behavior of its solution are studied more carefully. Using stretched variables, the formal asymptotic expansion of solution for the problem is constructed and the uniform validity of the solution is obtained by using the method of upper and lower solution. 相似文献
178.
本文研究了一类非线性系统解的正向有界性.运用常微分方程定性理论的方法,获得了这类方程所有解有界的充分条件和必要条件.推广和改进了已有文献中的结果. 相似文献
179.
U.Saleem M.Siddiq M.Hassan 《中国物理快报》2005,22(5):1076-1078
We give a noncommutative extension of a sinh-Gordon equation. We generalize a linear system and Lax representation of the sinh-Gordon equation in noncommutative space. This generalization gives a noncommutative version of the sinh-Gordon equation with extra constraints, which can be expressed as global conserved currents. 相似文献
180.
1.引言 代数Riccati方程是线性系统理论与设计的核心课题之一.矩阵的Hessenberg分解、Hamilton矩阵的平方约化分解、辛矩阵的QT分解是数值求解代数Riccati 方程的基本工具.关于 Hessenberg分解的研究工作有很多(参阅 [4]及其参考文献).最近, Sun[4]利用矩阵分裂算子研究了Hessenberg分解因子的扰动分析,并根据所得的扰动上界定义了分解因子的条件数.本文第 2节将运用局部展开方法引入 Hessenberg分解因子的条件数.有趣的是所定义的条件数与Sun引… 相似文献