首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 140 毫秒
1.
本文给出了系统dx/dt=A(t)x+g(t,x),g∈R‘,x∈R^N,ω周期解存在的充分条件,推广了文「1」中的Krasnoselskii的结果。  相似文献   

2.
文「1」给出模糊值函数在普通区间「a,b」上的N-L公式。本文在文「1」的基础上进一步给出模糊值函数区间「A,B」上的积分。这个积分是Ⅱ型糊集。文「3」已经指出(F2「1,1」,∪,∩,c)不是软代数,但这个积分是一个特殊Ⅱ型模糊集具有许多良好的代数性质,并存在着N-L公式。  相似文献   

3.
格上Ising模型的临界失真估计   总被引:1,自引:1,他引:0  
本文是我们先前工作「1」,「2」的继续,对格上Ising模型的临界失真dc的估计,Newman和Baker「6」证明了dc和Ising模型的Mayer级数之收敛半径R有以下关系:dc=R/(1+R),在「1」中匀提出了估计R及dc的新方法,并它计算了二维矩形格Z^2上Ising模型的临界失真dc,此文中我们继续应用此方法首次计算了定义在其它二维和三维格上Ising模型的临界失真dc,数值计算的结果  相似文献   

4.
胡晓山  彭厚富 《数学杂志》1996,16(4):539-542
本文讨论如下形式的希尔伯特空间中半线性随机发展方程Cauchy问题{dy(t)「Ay(t)=f(t,y(t))」dt+G(t,y(t))dw(t)y(0)=y0适度解的存在性。在一组条件下得到了解的整体存在性,推广了文「1」的存在性定理。  相似文献   

5.
闫桂英 《应用数学》1996,9(1):117-120
本文讨论图的(g,f)-因子分解问题,推广了文「1」关于图的因子分解的理论,改进了文「2」的一些结果,给出了一个图G是(g,f)-可因子化的若干充分条件。  相似文献   

6.
广义Lienard方程非平凡周期解的存在性   总被引:1,自引:0,他引:1  
严平  蒋继发 《应用数学》2000,13(3):31-34
本文给出了广义Lienard方程x+f(x)(x)x+g(x)=0存在非平凡周期解的两个充分条件,推广了文「4,5」中的结果,并且指出文「1」中的一个疏漏。  相似文献   

7.
平面定常系统的奇点指标问题   总被引:3,自引:0,他引:3  
本文引进S-交点的概念,用新的方法研究了平面定常系统一支上两相邻初等奇点的指标问题,把文「1」的有关结果推广到一般的平面定常系统,作为作用,证明了文「2」猜测(Ⅱ)对n次系统是正确的。  相似文献   

8.
本文将文[1]中AOR法和Jacobi法同时敛散的结论推广到GAOR法.证明了当Jacobi矩阵B非负时,解线性方程组Ax=b(A为不可约矩阵)的GAOR法(0≤γ<ω≤1,i=1,2,…,n)和Jacobi法同时敛散,给出了其谱半径ρ(LR,Ω)和ρ(B)之间的关系.  相似文献   

9.
本文提出了两类数值积分二阶周期性初值问题y〃=f(x,y),y(x0)=y0,y(x0)=y0具有检小相位延迟的显式两步法。这些方法推广和改进了文献「1」1-「7」中的某些方法。数值试验表明本文中的某些方法优于「1」-「7」中的某些方法。  相似文献   

10.
L-统计量的Edgeworth展开和Bootstrap逼近   总被引:4,自引:0,他引:4  
文「1」讨论了L-统计量的一种能达到0(1/√n)精确性的Bootstrap逼近,本文则在适当条件下,证明了上述Bootstrap逼近能达到精确性0(1/√n),并给出了L-统计量的一阶Edgeworth展开的估计。  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.
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.
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.
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   

20.
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   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号