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991.
Lei Zhang 《Numerical Functional Analysis & Optimization》2013,34(10):1190-1211
The finite difference approximations of the dynamical systems governed by two-dimensional complex Ginzburg–Landau equation was considered. For a fully discrete scheme, the solvability, stability and convergence are proved in discrete Sobolev spaces. Furthermore, the existence of global attractors 𝒜 h, τ of the discrete system and the upper semicontinuity dist(𝒜 h, τ, 𝒜) → 0 are obtained. 相似文献
992.
This paper is concerned with the stability of the spline collocation method for a class of integral equations of the first kind with logarithmic kernels. It is shown that a proper choice of the mesh size can be made in the numerical computation so that one will obtain an optimal rate of convergence for the approximate solutions. 相似文献
993.
Michael Nivala 《Physica D: Nonlinear Phenomena》2010,239(13):1147-1158
The stability of periodic solutions of partial differential equations has been an area of increasing interest in the last decade. The KdV equation is known to have large families of periodic solutions that are parameterized by hyperelliptic Riemann surfaces. They are generalizations of the famous multi-soliton solutions. We show that all such periodic solutions are orbitally stable with respect to subharmonic perturbations: perturbations that are periodic with period equal to an integer multiple of the period of the underlying solution. 相似文献
994.
Ali Fuat Yeniçerio?lu 《Journal of Mathematical Analysis and Applications》2007,332(2):1278-1290
In this paper, we study the behavior of solutions of second order delay differential equation
y″(t)=p1y′(t)+p2y′(t−τ)+q1y(t)+q2y(t−τ), 相似文献
995.
Shu-Rong Zhou Wan-Tong Li Gang Wang 《Journal of Mathematical Analysis and Applications》2006,324(1):397-408
In this paper, we investigate the existence and global stability of the positive periodic solutions of delayed discrete food chains with omnivory. With the help of continuation theorem in coincidence degree theory and Lyapunov functions, some sufficient conditions are obtained. The results show that, for such a system with omnivory, more conditions are required for the persistence of the positive periodic solutions than that of a linear food chain. On the other hand, omnivory makes no differences on the stability of the solutions. 相似文献
996.
Mourad Choulli 《偏微分方程通讯》2013,38(3):455-476
We prove a stability estimate related to the multi-dimensional Borg-Levinson theorem of determining a potential from spectral data: the Dirichlet eigenvalues λ k and the normal derivatives ?φ k /?ν of the eigenfunctions on the boundary of a bounded domain. The estimate is of Hölder type, and we allow finitely many eigenvalues and normal derivatives to be unknown. We also show that if the spectral data is known asymptotically only, up to O(k ?α) with α ? 1, then we still have Hölder stability. 相似文献
997.
In this paper, the numerical solution of fractional (non-integer)-order Cattaneo equation for describing anomalous diffusion has been investigated. Two finite difference schemes namely an explicit predictor–corrector and totally implicit schemes have been developed. In developing each scheme, a separate formulation approach for the governing equations has been considered. The explicit predictor–corrector scheme is the fractional generalization of well-known MacCormack scheme and has been called Generalized MacCormack scheme. This scheme solves two coupled low-order equations and simultaneously computes the flux term with the main variable. Fully implicit scheme however solves a single high-order undecomposed equation. For Generalized MacCormack scheme, stability analysis has been studied through Fourier method. Through a numerical test, the experimental order of convergency of both schemes has been found. Then, the domain of applicability and some numerical properties of each scheme have been discussed. 相似文献
998.
Yefei Li Yimin Gao Bing XiaoTing Min Shengqiang MaDawei Yi 《Applied Surface Science》2011,257(13):5671-5678
The adhesion, stability, electronic structure, and bonding of Fe/WC interfaces were studied using first-principles calculations. The preferred stacking sequence is HCP structure that Fe atoms continue the natural stacking sequence of the bulk WC. For two different interfaces with HCP stacking geometry (C-HCP and W-HCP), the work of adhesion of the optimized Fe/WC interfaces are 9.7 J m−2 for C-HCP and 5.1 J m−2 for W-HCP, respectively. The effects of the interface on the electronic structures of both the metal Fe and ceramic WC are mainly localized within the first and second layers of the interface. C-HCP interface has strong covalency and W-HCP interface is dominated by metallic bonds. The magnetic moments of Fe atoms at interface are decreased in both interfaces. Calculations of the interfacial energies provide theoretical evidence for the excellent wear behaviors of Fe/WC composites. Besides, the chemical bonding properties for the interfacial atoms are also discussed in this paper based on Milliken population method. 相似文献
999.
对连续激光二极管抽运Nd∶YVO4/Cr4+∶YAG被动调Q微晶片激光器输出激光重复频率的稳定性进行了理论和实验研究.结果表明,谐振腔内存在最佳净增益,可以使激光器工作在稳定区.通过优化腔内的净增益,耦合输出镜反射率为85%,饱和吸收体初始透射率为70%,抽运功率从1.05 W到1.20 W的情况下,激光器工作在稳定区.当抽运功率为1.16 W时,获得了重复频率为19.48 kHz,稳定性优于0.68%(RMS)的高重复频率激光输出.进一步分析了抽运功率抖动对输出激光重复频率稳定性的影响.结果表明,激光器进入稳定区之后,抽运功率的抖动是制约输出激光重复频率稳定性进一步提高的最主要因素.针对抽运功率抖动带来的影响,讨论了增益预抽运技术,并比较了其优缺点. 相似文献
1000.