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991.
曾云波 《数学年刊A辑(中文版)》1995,(1)
利用和三阶特征值问题相联系的零曲率方程表示理论,本文给出ModifiedBoussinesq方程在显式约束和高阶约束下的两种分解,ModifiedBoussineesq方程对x和t的依赖被分解为两个可交换的x-和t-有限维可积的Hamilton系统.这种分解提供了类似于变量分离的求解方法,通过解两个可交换的有限维可积系统可得到ModifiedBoussinesq方程的某些解. 相似文献
992.
Analysis of variable coefficient advection-diffusion problems via complex variable reproducing kernel particle method
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The complex variable reproducing kernel particle method (CVRKPM) of solving two-dimensional variable coefficient advection-diffusion problems is presented in this paper. The advantage of the CVRKPM is that the shape function of a two-dimensional problem is formed with a one-dimensional basis function. The Galerkin weak form is employed to obtain the discretized system equation, and the penalty method is used to apply the essential boundary conditions. Then the corresponding formulae of the CVRKPM for two-dimensional variable coefficient advection-diffusion problems are obtained. Two numerical examples are given to show that the method in this paper has greater accuracy and computational efficiency than the conventional meshless method such as reproducing the kernel particle method (RKPM) and the element- free Galerkin (EFG) method. 相似文献
993.
In this paper,using the fractional Fourier law,we obtain the fractional heat conduction equation with a time-fractional derivative in the spherical coordinate system.The method of variable separation is used to solve the timefractional heat conduction equation.The Caputo fractional derivative of the order 0 < α≤ 1 is used.The solution is presented in terms of the Mittag-Leffler functions.Numerical results are illustrated graphically for various values of fractional derivative. 相似文献
994.
Based on the generalized variational principle and B-spline wavelet on the interval (BSWI), the multivariable BSWI elements with two kinds of variables (TBSWI) for hyperboloidal shell and open cylindrical shell are constructed in this paper. Different from the traditional method, the present one treats the generalized displacement and stress as independent variables. So differentiation and integration are avoided in calculating generalized stress and thus the precision is improved. Furthermore, compared with commonly used Daubechies wavelet, BSWI has explicit expression and excellent approximation property and thus further guarantee satisfactory results. Finally, the effciency of the constructed multivariable shell elements is validated through several numerical examples. 相似文献
995.
Xue-min Ma 《应用数学学报(英文版)》2011,27(2):209-222
In this paper,we propose a customer-based individual risk model,in which potential claims by customers are described as i.i.d.heavy-tailed random variables,but different insurance policy holders are allowed to have different probabilities to make actual claims.Some precise large deviation results for the prospective-loss process are derived under certain mild assumptions,with emphasis on the case of heavy-tailed distribution function class ERV(extended regular variation).Lundberg type limiting results on the finite time ruin probabilities are also investigated. 相似文献
996.
王勇 《数学物理学报(B辑英文版)》2011,31(3):805-814
In this paper,we compute the first two equivariant heat kernel coeffcients of the Bochner Laplacian on differential forms.The first two equivariant heat kernel coeffcients of the Bochner Laplacian with torsion are also given.We also study the equivariant heat kernel coeffcients of nonminimal operators on differential forms and get the equivariant Gilkey-Branson-Fulling formula. 相似文献
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运用闵可夫斯基空间四维电磁场张量性质,研究介质中电磁场的相对论不变量,分别就每个电磁场张量本身、多个电磁场张量之间能够构成电磁场不变量的情形,给出独立的电磁场不变量的具体形式。结果表明,存在介质时独立的电磁场不变量只有六个,其形式可分别取为:B2·(E c)2、E·B c;H2·c2 D 2、cH·D;以及B·H·E·D、cB·D+E·H c. 相似文献