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1.
设1/p=1/q≈1:1且P〉1.通过引入一个适当的积分核函数和参数λ(λ〉-1),创建了一种新型Hardy~Hilbert型积分不等式.证明了其常数因子(p^λ=1+q^λ+1)Г(λ+1)是最佳的,其中Г(x)Г-函数.特别,当p=2时,得到了一种新的Hilbert型积分不等式.作为应用,给出了它的一种等价形式.  相似文献   

2.
带参数二阶方程x″+(λ+q(t))x=0与x″+λp(t)x=0的特征值求法在理论上是十分困难的.利用判别式与数学软件在计算机上可以较轻松的解决x″+λp(t)x=0型方程的特征值计算问题.  相似文献   

3.
一类分式不等式的统一证法   总被引:1,自引:1,他引:0  
不等式a2+b2≥2ab(a、b∈R)及其变形的应用已被人们广泛研究,笔者在教学中发现:如用ab、bλ分别代替a、b得一含参数的不等式a2b≥2aλ-bλ2 (b>0,λ>0,a∈R)()利用()可得一类分式不等式的统一证法:首先对要证的不等式进行适当变形,然后通过待定系数法求出λ,即得要证的不等式.这种证明方法具有思路单一,操作方便,学生易接受的特点.现以竞赛题、征解题为例进行说明.例1 设a、b、c∈R+,试证:a2a+b+b2b+c+c2a+c≥a+b+c2.(《数学通报》1995年第…  相似文献   

4.
该文在G.B.Folland与E.M.Stein研究的算子的基础上.拓展考虑了算子,其中λ+μ≠0且λ≠α/2n,μ≠—α/2n),证明了:如果,使得有限(其中ψa,b,1(z,t)=—4(λ+μ)ab(|z|2+1—it)a-1(|z|2+1+it)b-1,那么在分布的意义下将有.特别,当λ=μ=—1/2时,此结果即原来的Folland-Stein定理.  相似文献   

5.
设X:M→S^n+1州是(n+1)一维单位球面上不含脐点的超曲面,在S^n+1的Moebius变换群下浸入x的四个基本不变量是:一个黎曼度量g称为MSbius度量;一个1-形式圣称为Moebius形式;一个对称的(0,2)张量A称为Blaschke张量和一个对称的(0,2)张量B称为MSbius第二基本形式.李海中和王长平研究了满足如下条件的超曲面x:M→S^n+1:(i)Φ=0;(ii)存在可微函数λ和μ使A+λg+μB=0,他们证明了λ和μ都是常数,并且给出了这类超曲面的分类.对称的(0,2)张量A+λB也是Moebius不变量,称为浸入x的仿Blaschke张量,其中A是常数.因此李海中和王长平也就在Φ=0的条件下给出了A+λB的特征值全相等的超曲面X:M→s^n+1州的分类.本文对S^4中满足以下条件的超曲面进行完全分类:(i)Φ=0,(ii)对某一个常数λ,A+λB具有常数特征值.  相似文献   

6.
运用数论和图论技巧,得到了当λ(D)3时本原有向图D的广义指数exp(D,k)的界,这里λ(D)表示D中不同长的圈的类数,还证明了对任何整数n,t,不存在n阶本原有向图D,使得n2-tn+14(t+1)2+k-2<exp(D,k)<n2-(t-1)n+t+k-3.  相似文献   

7.
定理 设数列{αn}是等差数列,sn=α1^m+α2^m+…+αn^m,m∈N^*,则存在λi∈R(i=2,3,…,m+1),有g(n)=λm+1αn^m+1+λmαn^m+…+λ3αn^3+λ2αn^2,使{sn-g(n)}为等差数列.  相似文献   

8.
Jacobi矩阵的逆特征问题   总被引:8,自引:0,他引:8  
本文研究了两个Jacobi矩阵的逆特征问题:I给定实数λ,μ(λ>μ)和n维非零实向量x,y,求n阶Jacobi矩阵J,使Jx=λx,Jy=μy,且λ>λ2(J)>…>λi-1(J)>μ>λi+1(J)…>λn(J),或λi(J)>λ2(J)>…>λi-1(J)>λ>λi+1(J)>…>λn-1(J)>μ·II给定实数λ,μ(λ>μ)和n维非零实向量x,y,求n阶Jacobi矩阵J,使Jx=λx,Jy=μy,且λ1(J)>λ2(J)>…>λi-1(J)>λ>μ>λi+2(J)>…>λn(J).文中给出了问题I;II有唯一解的充要条件,并给出了解的表达式.  相似文献   

9.
本文讨论一类不满足 Nagumo条件的微分方程边值问题-u"=λ2+|u'|β,u(0)=u(1)=0正解的存在唯一性问题,其中β>2为常数,λ>0为参数.证明了对每一β>2,存在λ=λ(β)∈(0,π),边值问题存在属于C1[0,1]正解当且仅当λ∈(λ,π),此时正解唯一,当λ=λ(β)时,边值问题存在正解。 u∈C1(0,1)∩C[0,1],u'(0)=∞,u'(1)=-∞,并证明lim λ(β)=π  相似文献   

10.
本文通过引入两个函数u(x)和v(x),(x∈[0,+∞))建立了一个新的Hiblert型不等式,特别,u(m)=m+λ及v(n)=n+λ(∈No,λ=1/2,1)时,得到了Hilbert不等式的一个改进,作为应用,给出了Fejer-Riesz不等式的推广和改进.  相似文献   

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12.
张丽娜  吴建华 《数学进展》2008,37(1):115-117
One of the most fundamental problems in theoretical biology is to explain the mechanisms by which patterns and forms are created in the'living world. In his seminal paper "The Chemical Basis of Morphogenesis", Turing showed that a system of coupled reaction-diffusion equations can be used to describe patterns and forms in biological systems. However, the first experimental evidence to the Turing patterns was observed by De Kepper and her associates(1990) on the CIMA reaction in an open unstirred reactor, almost 40 years after Turing's prediction. Lengyel and Epstein characterized this famous experiment using a system of reaction-diffusion equations. The Lengyel-Epstein model is in the form as follows  相似文献   

13.
In this paper, we study the explicit representation and convergence of (0, 1; 0)-interpolation on infinite interval, which means to determine a polynomial of degree ≤ 3n - 2 when the function values are prescribed at two set of points namely the zeros of Hn(x) and H′n(x) and the first derivatives at the zeros of H′n(x).  相似文献   

14.
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   

15.
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   

16.
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   

17.
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   

18.
正Guest Editors:Hong Chen,Shanghai Jiao Tong University,Shanghai,China Guohua Wan,Shanghai Jiao Tong University,Shanghai,China David Yao,Columbia University,New York,USA Scope:Healthcare delivery worldwide has been fraught with high cost,low efficiency and poor quality of patient care service.For the field of operations research(OR),healthcare offers some of the biggest challenges as well as best opportunities in  相似文献   

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20.
Due to the resolution of current laser technology, the accuracy of corneal topography as measured by the videokeratoscope is no longer adequate to provide precise enough data for refractive surgery or for the fitting of customized contact lenses. We present an algorithm for recovering corneal topography that makes use of modern differential geometric techniques and numerical descent in Sobolev spaces. We believe this algorithm may be used with the photo- and videokeratoscope to increase the accuracy of the recovered corneal topography.  相似文献   

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