数学问题解答

１９９９年４月号问题解答（解答由问题提供人给出）１１８６设ｎ∈Ｎ,ｎ≥２,ｋ∈Ｒ＋,求函数ｙ＝ｘｎｘ－ｋ（ｘ∈（ｋ,＋∞））的最小值．解由均值不等式ｘ１＋ｘ２＋…＋ｘｎｎ≥ｎｘ１ｘ２…ｘｎ得ｘ１ｘ２…ｘｎ≤（ｘ１＋ｘ２＋…＋ｘｎｎ）ｎ∵ｙ＝ｘｎｘ－ｋ...     

一题、一法、一类

一题、一法、一类蒋涛（江苏滨海县中学２２４５００）例１设ｘ１，ｘ２，…，ｘｎ∈Ｒ＋，且ｘ１＋ｘ２＋…＋ｘｎ＝１，求证：ｘ１２１－ｘ１＋ｘ２２１－ｘ２＋…＋ｘｎ２１－ｘｎ≥１ｎ－１．（《数学通报》１９９３年７月号问题８４５）我们通过引入参数，给出一种新...     

二项式定理的推广

二项式定理的推广陈皓（湖北省邮电学校４３００７２）设ｍ≥１，对于多项式（１＋ｘ＋…＋ｘｍ）ｎ＝ｎｍｊ＝０ａｊｘｊ，约定展开式中含ｘｊ项的系数ａｊ＝ｆｍ（ｎ，ｊ），易知ｆ１（ｎ，ｊ）＝Ｃｊｎ．定理１若０≤ｔｉ≤ｍ（ｉ＝１，２，…，ｎ），则ｆｍ（ｎ，ｊ...     

关于Thue方程的解数

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．     

一类不可微优化的极大熵方法的收敛性

本文对求解如下问题的极大熵方法的收敛性质进行了研究：（Ｐ）ｍｉｎｆ（ｘ）＝ｍａｘ｛ｆｉ（ｘ）｝,ｓ,ｔ。ｘ∈Ω＝｛ｘ∈Ｒ＾ｎ│ｇｊ（ｘ）≤０,ｊ＝１,…,ｌ｝。其中ｍ≥１,ｌ≥０为整数;若ｌ＝０,规定Ω＝Ｒ＾ｎ。     

一类沿曲面的奇异积分算子的（L^∞,BMO）—有界性

设ｎ≥３，定义Ｔｆ（ｘ，ｘｎ）＝Ｐ．Ｖ．∫Ｒ＾ｎ－１ｂ（ｔ）Ｋ（ｔ）ｆ（ｘ＝ｔ，ｘｎ－Г（│ｔ│））ｄｔ，其中ｘ∈Ｒ＾ｎ－１，ｂ（ｔ）为Ｒ＾ｎ－１上的有界函数，Ｋ（ｔ）为Ｒ＾ｎ－１上满足Ｈｏｒｍａｎｄｅｒ条件的函数，且Г（ｓ）为〔０，∞）上的任意函数。本文给出了Ｔ为（Ｌ∞（Ｒ＾ｎ），ＢＭＯ（Ｒ＾ｎ））一型，或等价地（Ｈ＾１（Ｒ＾ｎ），Ｌ＾１（Ｒ＾ｎ））一型时，ｂ所应满足的充分必要条件。     

再谈一个不等式命题

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A Probe Method of Gradient Projection Type

§１．　ＩｎｔｒｏｄｕｃｔｉｏｎＷｅｃｏｎｓｉｄｅｒｔｈｅｆｏｌｌｏｗｉｎｇｏｐｔｉｍｉｚａｔｉｏｎｐｒｏｂｌｅｍ：（Ｐ）　　ｍｉｎｘ∈Ｘｆ（ｘ）（１）ｗｈｅｒｅＸ＝｛ｘ｜ｘ∈Ｅｎ,ｇｊ（ｘ）≤０,ｊ＝１,２,…,ｍ;ｇｊ（ｘ）＝０,ｊ＝ｍ＋１,…,ｍ＋ｌ｝,ｌｅｔＩ＝｛１,２,…,ｍ｝,Ｌ＝｛ｍ＋１,…,ｍ＋ｌ｝．Ｆｏｒｔｈｅｐｒｏｂｌｅｍ（Ｐ）ｗｉｔｈＬ＝,ｍａｎｙｅｆｆｉｃｉｅｎｔｐｒｏｊｅｃｔｉｏｎｔｙｐｅａｌｇｏｒｉｔｈｍｓ［１－１１］ｈａｖｅｂｅｅｎｐｒｏｐｏｓｅｄ．Ｉｎ［１２］,…     

秩为k的有限序列t—相交族

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关于广义Thue－Mahler方程的解数

设ａ，ｂ是非零整数，ｐ１，…，ｐｒ是不同的素数，Ｐ＝｛±｜ｍ１，…，ｍｒ是非负整数｝．设Ｋ是ｎ（ｎ≥３）次代数数域，α１，…，αｍ∈ｋ（１＜ｍ＜ｎ），△（α１，…，αｍ）是α１，…，αｍ的判别式，ｆ（ｘ１，…，ｘｍ）＝αＮｋ／Ｑ（α１ｘ１＋…＋αｍｘｍ）∈ｚ［ｘ１，…，ｘｍ］．本文证明了：当ｆ（ｘ１，…，ｘｍ）非退化且Ｐｉ△（α１，…，αｍ）（ｉ＝１，…，ｒ）时，方程ｆ（ｘ１，…，ｘｍ）＝ｂｙ，ｘ１，…，ｘｍ∈ｚ，ｇｃｄ（ｘ１，…，ｘｍ）＝１，ｙ∈Ｐ至多有（４Ｓｄ２）（Ｓｄ）组解（ｘ１，…，ｘｍ，ｙ），其中ｄ＝ｎ！，Ｓ＝ｒ＋ω是ｂ的不同素因数的个数，ｈＡ是Ｋ的类数．     

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.     

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.     

Qualitative Analysis of Bifurcating Solutions in the Lengyel-Epstein Model

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     

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.     

(0,1 ;0)-INTERPOLATION ON INFINITE INTERVAL (-∞, +∞)

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).     

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].