以单叶函数为符号的解析Toeplitz算子的拟相似性

Sz.-Nagy和Foias在[8]中证明拟相似的酉算子是酉等价的。Hoover在[5]中证明拟相似的等距算子是酉等价的。Halmos在[4]中指出拟相似的正规算子酉等价,而确有相似但非酉等价的次正规(subnormal)算子(见[4]问题152和156)。     

(δ,)-等距的稳定性

本文讨论了Banach空间之间非满射、非线性的弱等距逼近问题.在某些条件假设下,对(δ,(?))-等距算子的稳定性给出了一些肯定的结果,从而修正并推广了文[1—4]中的一些结果.     

(δ,)-等距的稳定性

本文讨论了Banach空间之间非满射、非线性的弱等距逼近问题.在某些条件假设下,对(δ,(?))-等距算子的稳定性给出了一些肯定的结果,从而修正并推广了文[1—4]中的一些结果.     

(δ,ψ)-等距的稳定性

本文讨论了Banach空间之间非满射、非线性的弱等距逼近问题.在某些条件假设下,对(δ,ψ)-等距算子的稳定性给出了一些肯定的结果,从而修正并推广了文[1-4]中的一些结果.     

空间型中紧致无边子流形上的第一特征值

得到了两个关于空间形式中紧致无边子流形的广义位置向量场和其上Laplace算子第一特征值λ1的积分不等式,并由此首先给出了λ1与其上界间的间隔估计,其次得到了此紧致无边子流形等距浸入在空间形式的测地超球面或等距于测地超球面的充分条件,推广了Deshmukh[6]在欧氏空间中的相应结论.     

Ⅱ空间上的酉算子(Ⅱ)

对于Krein空间Ⅱ上的自共轭算子下面的结果是熟知的:A是Ⅱ上有界自共轭算子,是正则分解,如果是紧算子,则存在A的极大半负不变子空间。但是,在[5]中并未出现不变子空间的形式,这对进一步的讨论是不方便的。本文是文[1]的继续,我们将证明在种种(不同于正[5]的)假设下的酉算子存在极大半负不变子空间,我们还将给出不变子空间的形式,酉算子的谱和结构。     

赋范空间单位球之间的1-Lipshcitz算子

证明了赋范空间单位球之间任意保一的1-Lipshcitz算子在假设像空间是严格凸的,或者算子是满的条件下是定义在全空间上的线性等距算子在单位球上的限制.同时,也给出了这个结果的一些应用,以及当两个赋范空间是严格凸时推广了的结果.     

样条变差缩减算子迭代极限的一个简单证明

一、引言在[1]和[2]中,胡莹生、徐叔贤利用 Markov 链终极条件概率的有关结果,确定了一类变差缩减算子的迭代极限.本文采用作者在[3]中使用的技巧,利用多项式样条的若干基本知识,不但简单地得出了[1,2]的结果,并且给出了迭代收敛速度的估计.对于等距分划的三次样条,所给的误差估计在某种意义上是最好的.     

赋β-范空间中单位球面间的等距算子的线性延拓

本文得到了等距映射的线性延拓的一般结果:设E,F是赋范(或β-严格凸赋β-范)线性空间,若V_0:S_1(E)→S_1(F)是等距,且对任意的x,y∈S_1(E),有‖V_0x-|(?)|V_0y‖≤‖x-|(?)|y‖,(?)∈R,则V_0必可延拓到全空间上等距算子(或线性等距算子)。特别,当E,F是赋范线性空间,V_0是满射或F为严格凸空间时,则V_0必可延拓为全空间的线性等距算子,从而推广了文[3～5]中的相应结果。     

多圆柱上Bloch型空间之间的等距复合算子

简单介绍了一些解析函数构成的Banach空间上的满等距的结果,然后刻画了多圆柱上α-Bloch空间复合算子的等距,并得到了复合算子等距的充要条件.     

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.     

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     

(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).     

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].