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821.
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823.
824.
Burgers方程的一种并行计算法 总被引:5,自引:1,他引:5
给出了求解Burgers方程的交替分段隐格式,讨论了方法的线性化绝对稳定性,并进行了数值试验.该方法具有并行本性,适合在高性能多处理器的并行计算机上使用. 相似文献
825.
杂化轨道理论近来有了长足的发展,杂化轨道的构造方法主要有群论方法最大重叠方法,自然杂化轨道法和其它以分子轨道为基础构造杂化轨道的方法等。其中最大重叠杂化轨道不仅满足正交化条件而且能较定量地考虑到配体轨道的作用,因而已经得到广泛应用。本文在最大重叠原理的基础上得到了扩展基杂化轨道的解析形式。扩展基杂化轨道对一给定几何构型的分子M(X_1X_2…X_n),其中心原子M的n个杂化轨道与诸配体{X_i}形成一组方向键。M的杂化轨道(HO)和原子轨道(AO)可分别作为该分子对称操作群的表示之基。这两种不同基的表示进行约化之后,属于同一不可约表示的HO和AO是线性相 相似文献
826.
Shweta . Saddam Hussain Rajesh Kumar Rajesh Kumar. 《Journal of Applied Analysis & Computation》2025,15(1)
The accelerated homotopy perturbation Elzaki transform method (AHPETM), which is based on the homotopy perturbation method (HPM), is used in this article to solve the Burgers equation and system of Burgers equations. AHPETM presents the Elzaki integral transform as a pre-treatment in combination with the decomposition of nonlinear variables to speed up the convergence of the HPM solution to its precise values. When the suggested method\"s findings are compared to HPM\"s, the results show a considerable improvement. Theoretical convergence analysis and error estimations are also crucial in this work. Multiple numerical examples of 1D, 2D, and 3D Burgers equations, as well as systems of 1D and 2D Burgers equations, are examined to confirm the method\"s accuracy. Interestingly, the proposed approach offers the closed-form results to most of the problems, which are essentially the exact solutions. 相似文献
827.
Deng‐Shan Wang Jiang Liu Zhifei Zhang 《Mathematical Methods in the Applied Sciences》2016,39(12):3516-3530
In this paper, we investigate the integrability and equivalence relationships of six coupled Korteweg–de Vries equations. It is shown that the six coupled Korteweg–de Vries equations are identical under certain invertible transformations. We reconsider the matrix representations of the prolongation algebra for the Painlevé integrable coupled Korteweg–de Vries equation in [Appl. Math. Lett. 23 (2010) 665‐669] and propose a new Lax pair of this equation that can be used to construct exact solutions with vanishing boundary conditions. It is also pointed out that all the six coupled Korteweg–de Vries equations have fourth‐order Lax pairs instead of the fifth‐order ones. Moreover, the Painlevé integrability of the six coupled Korteweg–de Vries equations are examined. It is proved that the six coupled Korteweg–de Vries equations are all Painlevé integrable and have the same resonant points, which further determines the equivalence among them. Finally, the auto‐Bäcklund transformation and exact solutions of one of the six coupled Korteweg–de Vries equations are proposed explicitly. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
828.
We consider the Harniltonian system consisting of scalar wave field and a single particle coupled in a translation invariant manner. The point particle is subject to a confining external potential. The stationary solutions of the system are a Coulomb type wave field centered at those particle positions for which the external force vanishes. We prove that solutions of finite energy converge, in suitable local energy seminorms, to the set of stationary solutions in the long time limit t f oo. The rate of relaxation to a stable stationary solution is determined by spatial decay of initial data. 'Supported partly by French-Russian A.M.Liapunov Center of Moscow State University, by research grants of RFBR (9601-00527) and of Volkswagen-Stiftung. 相似文献
829.
Justin Holmer 《偏微分方程通讯》2013,38(8):1151-1190
We prove local well-posedness of the initial-boundary value problem for the Korteweg–de Vries equation on right half-line, left half-line, and line segment, in the low regularity setting. This is accomplished by introducing an analytic family of boundary forcing operators. 相似文献
830.
Xiaoli Kong 《代数通讯》2013,41(6):2177-2183
The baby Tits–Kantor–Koecher (TKK) algebra constructed from the smallest (nonlattice) semilattice is related to the “smallest” extended affine Lie algebras other than the finite dimensional simple Lie algebras and the affine Kac–Moody algebras. In this article, we classify the finite dimensional irreducible representations for the baby TKK algebra. It turns out that such representations can be lifted from modules of direct sums of finitely many copies of the simple Lie algebra sp 4(?). 相似文献