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201.
We continue to investigate strongly and weakly Lie remarkable equations, which we defined in a recent paper. We consider some
relevant algebras of vector fields on ℝk (such as the isometric, affine, projective, or conformal algebras) and characterize strongly Lie remarkable equations admitted
by the considered Lie algebras.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 151, No. 3, pp. 486–494, June, 2007. 相似文献
202.
四阶方程两点边值问题Hermite有限元解的渐近展式与外推 总被引:1,自引:0,他引:1
1引言有限元解的渐近展式是提高微分方程数值解精度的重要工具,比如亏量校正和外推就是建立在有限元解的渐近展式的基础之上.许多作者对此进行了大量的研究(见[1]-[4]),特别是文[1],提出了在研究有限元解的渐近展式中十分有用的能量嵌入技巧.本文利用能量嵌入定理得到了四阶方程两点边值问题Hermite有限元解及其二阶平均导数的渐近展式,进一步我们还讨论了它们的Richardson外推公式.考虑四阶方程两点边值问题 相似文献
203.
A generalized inverse problem for the identification of the absorption coefficient for a hyperbolic system is considered. The well-posedness of the problem is examined. It is proved that the regular part of the solution is an L 2 function, which reduces the inverse problem to minimizing the error functional. The gradient of the functional is determined in explicit form from the adjoint problem, and approximate formulas for its calculation are derived. A regularization algorithm for the solution of the inverse problem is considered. Numerical results obtained for various excitation sources are displayed. 相似文献
204.
We consider systems of two pure one-dimensional diffusion equations that have considerable interest in Soil Science and Mathematical Biology. We construct non-local symmetries for these systems. These are determined by expressing the equations in a partially and wholly conserved form, and then by performing a potential symmetry analysis on those systems that can be linearised. We give several examples of such systems, and in a specific case we show how linearising and hodograph-type mappings can lead to new solutions of the diffusion system. 相似文献
205.
We consider the problem of solving the integral form of the radiative transfer equation in an atmosphere with optical thickness τ0?1. We propose two methods transforming this problem to a finite set of the independent problems of the same type set in an atmosphere with optical thickness much less then τ0. The error estimates are derived. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
206.
This paper studies the stability and boundedness of the solutions of Volterra integral differential equations with infinite delay in the phase space (Ch, |·|h), the h-uniform stability, h-uniformly asymptotic stability and h-boundedness of solutions are obtained. 相似文献
207.
Wengu Chen Yixin Lai 《分析论及其应用》2006,22(2):195-200
Let μ be a Borel measure on Rd which may be non doubling. The only condition that μ must satisfy is μ(Q) ≤ col(Q)n for any cube Q () Rd with sides parallel to the coordinate axes and for some fixed n with 0 < n ≤ d. The purpose of this paper is to obtain a boundedness property of fractional integrals in Hardy spaces H1 (μ). 相似文献
208.
Hideshi Yamane 《Proceedings of the American Mathematical Society》2006,134(11):3353-3361
We study the lifespan of solutions to fully nonlinear Cauchy problems with small real- or complex-analytic data. Our proofs are based on the method of majorants and the fixed point theorem for a contraction mapping.
209.
考虑一类p-Laplacian算子型泛函微分方程的奇异边值问题,利用锥不动点定理,得到了其正解及多个正解存在的充分条件. 相似文献
210.
In this paper, we prove Lp-boundedness of hyperbolic singular integral operators for kernels satisfying weakened regularity conditions, where 1
相似文献