对《三角形角平分线构成三角形的初探》中定理5的改进

文[1]中证明了三角形角平分线的几个性质,笔者觉得定理5还可以改进.先看文[1]中的定理4,定理5以及定理5的证明过程.定理4△ABC中,三边分别是a,b,c,三角     

一个定理的另证与推广

文[1]给出了如下定理:定理△ABC的内切圆与BC,CA,AB依次相切于点D,E,F,圆心为I,BC=a,CA=b,AB=c,则a ID b IE c IF=0.图1三角形下面给出它的一个简证及推广.要证明a ID b IE c IF=0.只需证明aID|ID| bIE|ID| cIF|ID|=0.易知,ID|ID|,IE|ID|,IF|ID|分别为与ID,IE,IF同向的单位向量     

“关于厄米特矩阵的一个不等式”的几点注记

<正> 文[1]提出并证明了下面的定理.设 A_j,B_j,…,C_j(j=1,2,…,k) 都是正定的同阶 (≥2) 厄米特矩阵,α,β,…,γ都是正实数,且 α+β+…+γ=1,则有sum from i=1 to k|A_j|~α|B_j|~β…|C_j|~γ<|sum from i=1 to k A_i|~α·|sum from i=1 to k B_i|~β…|sum from i=1 to k C_i|~γ.以下几点意见,供参考.第一,文[1]中的引理1和引理2是早有的结果.引理1见[2]p.15,[3]p.16及p.13,引理2是 Minkowski 行列式定理的直接推论,见[4].事实上,文[1]的定理是 H(?)lder 不等式和 Minkowski 行列式定理的自然结果.因为     

关于《一类奇异边值问题的正解》的注记

文[4]通过构造反例断言文[1]中定理的必要性证明有误,本文首先指出文[4] 的这个断言不正确,然后对文[4]中定理2.1作了本质性的改进.     

R~N空间中退化的logistic型拟线性椭圆方程正解存在唯一性

本文研究下列退化的logistic型p-Laplacian方程:-△Apu=a(x)|u|p-2u- b(x)|u|q-1u,x∈RN(N≥2)．在对系数a(x),b(x)在无穷远处的性质加以一般限制,得出了正解唯一存在性定理．我们的结果改进了文[1]和[2]中的相应结果．     

“一个几何命题的推广”的向量证法

文[1]中对一道平面几何题进行了推广,读后深受启发,但笔者试着用向量证明文[1]中的命题.现介绍如下:为了方便用向量证明文[1]中的命题,先给出一个引理已知向量a=(m,n),b=(p,q),现定义向量间的一种运算“*”:c=a*b=(mp-nq,mq np).则c是这样一个向量:把a的模变为原来的|b|倍,并按     

一个代数不等式推广的简证与类似结论

文[1]曾提出一个代数不等式:猜想若a,b,c为满足a+b+c=1的正数,则(a+1/b)~(1/2)+(b+1/c)~(1/2)+(c+1/a)~(1/2)≥30~(1/2)①文[2]给出①式的证明,文[3]运用赫尔德不等式将①式加强推广为:定理1若a,b,c为满足a+b+c=1的正     

度量空间中的完全覆盖定理

<正> 文[1]给出了如下概念和定理: 定义1 [a,b]的一个闭子区间族C叫做[a,b]的一个完全覆盖,如果对每个x属于[a,b]都存在一个正数δ_x,使对[a,b]的每一个包含x的闭子区间I,当I的长度|I|小于δ_x时,I属于     

关于Fourier级数L~1收敛的Tauberian定理

文献[1],[2]连续发表了关于Fourier级数L~l收敛的若干Tauberian定理。本文指出:文[2]中的定理2.1,2.2的条件是多余的。文[1]中的类似条件也是多余的。相应地这些定理的推论都可得到改进。     

高维正弦定理的再改进及其应用

本文借助于Cayley-Mensger行列式定义了n维欧氏空间E~n中单形A顶角A_k(1≤k≤n+1)的正弦值,由此得到了新的正弦定理。这一定理大大地改进了文[1]和[2]中所给出的正弦定理,并且弥补了文[1]与[2]中的好多不足之处,在第3节中,还给出了新上弦定理的应用(即性质定理2)。     

A REPRESENTATION FORMULA RELATED TO SCHR(O)DINGER OPERATORS

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.     

On a class of self-similar processes with stationary increments in higher order Wiener chaoses

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.     

On a class of Riemann surfaces

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.     

CONTENTS OF VOLUME 30

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Instructions for contributions

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     

Journal of Mathematical Research with Applications Guide for Authors

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.     

Staircase transportation problems with superadditive rewards and cumulative capacities

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].