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1.
关于指数型丢番图方程的整数解   总被引:4,自引:0,他引:4  
乐茂华 《数学进展》1994,23(5):385-395
本文简要地介绍了有关S-单位方程、Ramanujan-Nagell方程、Thue-Mahler方程、LeVeque方程、Catalan方程、Pillai方程等指数型丢番图方程整数解的最新结果。这些结果大多是用Thue-Siegle-Roth-Schmidt方法和Gel’fond-Baker方法得到的。  相似文献   

2.
一类非线性波动方程的显式精确解   总被引:14,自引:0,他引:14  
本文用直接方法和假设的一种结合求出了一类较广泛的非线性波动方程utt-a1uxx+a2ut+a3u+a4uS^2+a5u^3=0的一些显式精确行波解,贱个有重要的非线性数学物理方程,如φ^4方程,Klein-Gordon方程,Sine-Gordon方程,及Sinh-Gordon方程的近似,Landau-Ginzburg-Higgs方程,Duffing方程,非线性电报方程等都可作为该方程的特殊情形得  相似文献   

3.
本文证明了粘流-无粘干扰流动理论基本控制方程-简化的Navier-Stokes方程变分问题几种迭代序列的收敛性,并探讨了其算子方程的性质。本文的结论对于简化N-S方程的数值计算具有指导意义。  相似文献   

4.
外部流动的Oseen耦合方法,I:Oseen耦合逼近   总被引:1,自引:0,他引:1  
何银年  李开泰 《数学学报》2000,43(6):969-974
这篇文章考虑了具有非齐次边界条件的二维非定常外部Navier-Stokes方程.通过将内部区域的Navier-Stokes方程和外部区域的Oseen方程相耦合,得到了Navier-Stokes问题的逼近问题: Oseen耦合问题,此外,我们证明了 Oseen耦合方程弱解的存在性,唯一性和收敛精度.  相似文献   

5.
本文证明了粘流-无粘干扰流动理论[1,2]基本控制方程─—简化的Navier-Stokes方程变分问题几种迭代序列的收敛性,并探讨了其算子方程的性质。本文的结论对于简化N-S方程的数值计算具有指导意义。  相似文献   

6.
本文对Navier-Stokes方程与热传导方程的性质进行了比较。法国数学家、偏微分方程权威J.Leray教授在其对Navier-Stokes方程的研究中,曾由热传导方程出发而求得Navier-Stokes方程某种初(边)值问题的适定性结果 ̄[2].巴黎十一大学的R.Temam等专家、教授也曾多次提出过将两类方程类比的疑问。本文试将其中根本不同点做了叙述和例证。  相似文献   

7.
本文应用分层理论,证明了第一类广义Navier-Stokes方程是一类不稳定方程。  相似文献   

8.
尚亚东 《应用数学》2000,13(3):35-39
本文研究非线性Sobolev-Calpern方程的初边值问题整体解的不存性即解的爆破问题,用能量估计方法并借助于Jensen不等式证明了非线性Soboliv-Galpern方程各种初边值问题在某些假设下不存在整体解。  相似文献   

9.
本文得到了Stein流形局部q-凸域上(r,S)型微分形式的带权因子的同伦公式及其-方程的带权因子的解.  相似文献   

10.
邱春晖 《数学杂志》2000,20(1):76-82
本文得到了Stein流形局部q-凸域上(r,S)型微分形式的带权因子的同伦公式及其e-方程的带权因子的解。  相似文献   

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12.
As early as in 1990, Professor Sun Yongsheng, suggested his students at Beijing Normal University to consider research problems on the unit sphere. Under his guidance and encouragement his students started the research on spherical harmonic analysis and approximation. In this paper, we incompletely introduce the main achievements in this area obtained by our group and relative researchers during recent 5 years (2001-2005). The main topics are: convergence of Cesaro summability, a.e. and strong summability of Fourier-Laplace series; smoothness and K-functionals; Kolmogorov and linear widths.  相似文献   

13.
We study a class of self-similar processes with stationary increments belonging to higher order Wiener chaoses which are similar to Hermite processes. We obtain an almost sure wavelet-like expansion of these processes. This allows us to compute the pointwise and local Hölder regularity of sample paths and to analyse their behaviour at infinity. We also provide some results on the Hausdorff dimension of the range and graphs of multidimensional anisotropic self-similar processes with stationary increments defined by multiple Wiener–Itô integrals.  相似文献   

14.
Schr(o)dinger operator is a central subject in the mathematical study of quantum mechanics.Consider the Schrodinger operator H = -△ V on R, where △ = d2/dx2 and the potential function V is real valued. In Fourier analysis, it is well-known that a square integrable function admits an expansion with exponentials as eigenfunctions of -△. A natural conjecture is that an L2 function admits a similar expansion in terms of "eigenfunctions" of H, a perturbation of the Laplacian (see [7], Ch. Ⅺ and the notes), under certain condition on V.  相似文献   

15.
It is considered the class of Riemann surfaces with dimT1 = 0, where T1 is a subclass of exact harmonic forms which is one of the factors in the orthogonal decomposition of the spaceΩH of harmonic forms of the surface, namely The surfaces in the class OHD and the class of planar surfaces satisfy dimT1 = 0. A.Pfluger posed the question whether there might exist other surfaces outside those two classes. Here it is shown that in the case of finite genus g, we should look for a surface S with dimT1 = 0 among the surfaces of the form Sg\K , where Sg is a closed surface of genus g and K a compact set of positive harmonic measure with perfect components and very irregular boundary.  相似文献   

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17.
正Applied Mathematics-A Journal of Chinese Universities,Series B(Appl.Math.J.Chinese Univ.,Ser.B)is a comprehensive applied mathematics journal jointly sponsored by Zhejiang University,China Society for Industrial and Applied Mathematics,and Springer-Verlag.It is a quarterly journal with  相似文献   

18.
正Journal overview:Journal of Mathematical Research with Applications(JMRA),formerly Journal of Mathematical Research and Exposition(JMRE)created in 1981,one of the transactions of China Society for Industrial and Applied Mathematics,is a home for original research papers of the highest quality in all areas of mathematics with applications.The target audience comprises:pure and applied mathematicians,graduate students in broad fields of sciences and technology,scientists and engineers interested in mathematics.  相似文献   

19.
A cumulative-capacitated transportation problem is studied. The supply nodes and demand nodes are each chains. Shipments from a supply node to a demand node are possible only if the pair lies in a sublattice, or equivalently, in a staircase disjoint union of rectangles, of the product of the two chains. There are (lattice) superadditive upper bounds on the cumulative flows in all leading subrectangles of each rectangle. It is shown that there is a greatest cumulative flow formed by the natural generalization of the South-West Corner Rule that respects cumulative-flow capacities; it has maximum reward when the rewards are (lattice) superadditive; it is integer if the supplies, demands and capacities are integer; and it can be calculated myopically in linear time. The result is specialized to earlier work of Hoeffding (1940), Fréchet (1951), Lorentz (1953), Hoffman (1963) and Barnes and Hoffman (1985). Applications are given to extreme constrained bivariate distributions, optimal distribution with limited one-way product substitution and, generalizing results of Derman and Klein (1958), optimal sales with age-dependent rewards and capacities.To our friend, Philip Wolfe, with admiration and affection, on the occasion of his 65th birthday.Research was supported respectively by the IBM T.J. Watson and IBM Almaden Research Centers and is a minor revision of the IBM Research Report [6].  相似文献   

20.
In this paper, we study the commutators generalized by multipliers and a BMO function. Under some assumptions, we establish its boundedness properties from certain atomic Hardy space Hb^p(R^n) into the Lebesgue space L^p with p 〈 1.  相似文献   

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