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1.
本文用概率方法讨论了如下拟线性扩散方程的广义Dirichlet问题。 1/2△u(x)+q(x)u(x)+f(x,u)=au(x)/atx=(x,t{ limu(x)=q(z),z∈aD∩(D^c)^r且z为q连续。 其中D为d+1维欧氏空间R^d中的一个有界区域,aD的边界,q∈Kd,q在DHo  相似文献   

2.
吴方同 《数学学报》1996,39(6):825-832
设ΩR(n+1),其边界 Ω在x0∈ Ω附近局部为{t=0},且对m阶偏微分算子P(x,t,Dx,Dt)是非特征的.令σm(P)(x,t,ζ,T)=0关于T有m个实根(包括重根)λj(x,t,ζ),(j=1,...,m),且它们是对合组.在P(x,t,Dx,Dt)满足Levi条件下,则其Dirichlet边值问题的解u的C∞奇性在边界的反射锥族中是不变的.  相似文献   

3.
一类Dirichlet边值问题的正解存在性   总被引:2,自引:0,他引:2  
程建纲 《数学学报》2002,45(2):301-306
本文对Dirichlet边值问题y″-f(t,y)=0,y(0)=c>0,y(1)= 0,给出正解的存在性结论,其中函数f(t,y)可以是变号函数,并且可能在y=0处具有奇异性.  相似文献   

4.
四元数分析中超球与双圆柱区域上的正则函数   总被引:10,自引:0,他引:10  
本文讨论了四元数分析中的正则函数U(z)(满足方程zU(z)=0,z=x1+ix2+jx3-kx4)及其边值问题,给出了超球与双圆柱区域上的四元数正则函数的Cauchy积分公式,获得了一般区域上正则函数的无穷次可微性;给出了定义在超球与双圆柱区域边界上的四元数函数可正则开拓到区域内的条件;讨论了满足非齐次方程zF=f的四元函数F(z)的Dirichlet和Neumann边值问题;获得了超球与双圆柱区域上这两种边值问题解的积分表示.  相似文献   

5.
乐茂华 《数学学报》1996,39(6):728-732
设m是正整数,f(X,Y)=a0Xn+a1X(n-1)Y+...+anYn∈Z[X,Y]是Q上不可约化的叫n(n≥3)次齐次多项式。本文证明了:当gcd(m,a0)=1,n≥400且m≥10(35)时,方程|f(x,y)|=m,x,y∈z,gcd(x,y)=1,至多有6nv(m)组解(x,y),其中v(m)是同余式F(z)=f(z,1)≡0(modm)的解数。特别是当gcd(m,DF)=1时,该方程至多有6n(ω(m)+1)组解(x,y),其中DF是多项式F的判别式,ω(m)是m的不同素因数的个数.  相似文献   

6.
王传芳在文[1]中研究了一类非线性退化椭圆方程-Di(x1ma·Diu)=|u|s-1·u+h(x)的Dirichlet问题,建立了一套指数p=2的带权Sobolev空间及其嵌入和嵌入紧性理论,用扰动方法得到问题无穷多解的存在性.本文将此理论推广到指数P≥2的情形,据此推广了的理论研究一类非线性退化椭圆方程-Di(|xm|a·|Du|p-2·Diu)=f(x,u)的Dirichlet问题.利用临界点理论得到问题的非平凡弱解及无穷多个非平凡弱解.同时对解的不存在性进行了讨论.  相似文献   

7.
本文考虑下面的Dirichlet问题利用粘性解理论证明了;当H,Г满足一定条件时,(DP)的粘性解u(x,t)满足:如果ψ∈Ca,a/2,则u(x,t)∈Ca,a/2,若ψ=0,则u(x,t)是Lipschitz连续的.  相似文献   

8.
本文讨论了二阶椭圆型方程-Δu=f(x,u),x∈Ω的Dirichlet问题u|Ω=0的很弱解u∈W01,r(Ω)(1<r<2)关于区域Ω的连续性及很弱边值问题的很弱解的唯一性.  相似文献   

9.
一类拟线性椭圆型偏微分方程的先验界的估计   总被引:1,自引:0,他引:1  
近几年对边值问题-div(|Du|p-2Du)=λf(u)}在Ω上u|(?)Ω=0正解方面已经得到了许多结果.这里λ>0,Ω是有界区域和对s≥0,f(s)≥0.在本文中在条件N≥p>1,Ω=B={x∈RN,|x|<1}和f∈C1(0,∞)∩C0([0,∞)),f(0)=0,研究了这类问题的正对称解的先验界估计.  相似文献   

10.
一类非自治迭代泛函微分方程   总被引:5,自引:0,他引:5  
本文研究了一类非自治迭代泛函微分方程x′(t)=(x2(t)-t2)f(x(x(t)))(其中f∈C(R,R),单调递增,zf(z)>0,z≠0)满足初始条件x(σ)=σ>0,或满足初始条件x(σ)=-σ<0的解的性态、解的存在性及延拓问题.  相似文献   

11.
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.
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   

14.
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   

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.
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   

17.
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   

18.
19.
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   

20.
In this paper we study best local quasi-rational approximation and best local approximation from finite dimensional subspaces of vectorial functions of several variables. Our approach extends and unifies several problems concerning best local multi-point approximation in different norms.  相似文献   

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