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991.
The stability of high‐frequency potential surface waves at a dense magnetized plasma – metal interface with respect to a low‐frequency plasma density modulation is studied in the point of view of the surface waves control. The discussion is addressed to the situation, when an external steady magnetic field is directed perpendicularly to the interface. The nonlinear interaction process of the high‐frequency surface wave, its satellites and the low‐frequency plasma density perturbation is investigated. It is shown that the low‐frequency plasma density perturbation can be represented as a superposition of forced waves of surface and volume types and can lead to an additional attenuation of the surface waves. This attenuation arises when the surface wave amplitude exceeds the threshold value. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
992.
R. R. Parwani 《Theoretical and Mathematical Physics》2007,152(1):1012-1016
The arguments leading to a nonlinear generalization of the Schrödinger equation in the context of the maximum uncertainty principle are reviewed. The exact and perturbative properties of that equation depend on a free regulating/interpolating parameter η, which can be fixed using energetics as is shown here. A linear theory with an external potential that reproduces some unusual exact solutions of the nonlinear equation is also discussed, together with possible symmetry enhancements in the nonlinear theory. 相似文献
993.
非线性非均衡蛛网模型的动态分析 总被引:5,自引:0,他引:5
黄赜琳 《数学的实践与认识》2004,34(3):40-45
描述单商品市场价格波动的蛛网模型是动态经济分析中的经典模型 ,证明了由模型 ( )所生成的价格序列在一定的条件下不会出现 3以上周期运动和混沌现象 ,并对其进行稳定性分析 ,得到模型关于均衡价格稳定的六个判别定理 . 相似文献
994.
In this paper, a fully discrete format of nonlinear Galerkin mixed element method with two-step discretization of time for the non stationary conduction-convection problems is presented. The existence and the convergence of the fully discrete mixed element solution are shown. On the basis of [9] and [10], we have proved that the schemes have second-order convergence accuracy for the time discretization. 相似文献
995.
非线性对流扩散方程沿特征线的多步有限体积元格式 总被引:4,自引:1,他引:3
对于二维非线性对流扩散方程构造了沿特征线方向的多步有限体积元格式.关于空间采用二次有限体积元方法离散,关于时间采用多步法进行离散,获得了O(Δt^2 h^2)形式的误差估计.本文最后给出的数值算例表明了方法的有效性. 相似文献
996.
997.
一类非线性方程组的奇摄动问题 总被引:20,自引:1,他引:19
本文在较弱的假设下.用校正边界层的方法得到了一类非线性奇摄动方程组的一致有效渐近展开式.并得到了其渐近性态. 相似文献
998.
Lubomír Kubáček 《Applications of Mathematics》2004,49(2):81-95
In nonlinear regression models an approximate value of an unknown parameter is frequently at our disposal. Then the linearization of the model is used and a linear estimate of the parameter can be calculated. Some criteria how to recognize whether a linearization is possible are developed. In the case that they are not satisfied, it is necessary to take into account either some quadratic corrections or to use the nonlinear least squares method. The aim of the paper is to find some criteria for an ordering linear and quadratic estimators. 相似文献
999.
J.L. Alejandre Ana Allueva Jose Miguel Gonzalez 《Computational Optimization and Applications》2004,27(1):83-93
The degree of difficulty is an important concept in classical geometric programming theory. The dual problem is often infeasible when the degree of difficulty is negative and little has been published on this topic. In this paper, an alternative procedure is developed to find the optimal solution for the posynomial geometric programming problem with a negative degree of difficulty. First an equivalent problem was constructed with a positive degree of difficulty and the general posynomial geometric programming problem was solved using an original method previously developed by the authors. This method avoids the difficulty of non-differentiability of the dual objective function in the classical methods classified as dual. It also avoids the problem that appears when the feasible region for the dual problem is formed by an inconsistent system of linear equations. 相似文献
1000.
Based on the eigensystem {λj,φj}of -Δ, the multiple solutions for nonlinear problem Δu f(u) =0 in Ω, u=0 on Ω are approximated. A new search-extension method (SEM), which consists of three steps in three level subspaces, is proposed. Numerical simulations for several typical nonlinear cases, i.e. f(u) = u~3,u~2(u-p),u~2(u~2 -p), 相似文献