弱模余代数的结构定理

设H为弱Hopf代数,C为弱右H-模余代数,令C=C/C·ker L.利用Smash余积来研究弱模余代数上的结构定理,并给出了C与C×H作为余代数同构的条件.     

D.C.隶属函数模糊集及其应用(II)——D.C.隶属函数模糊集的万能逼近性

本文是D.C.隶属函数模糊集及其应用系列研究的第二部分。指出在实际问题中普遍选用的三角形、半三角形、梯形、半梯形、高斯型、柯西型、S形、Z形、π形隶属函数模糊集等均为D.C.隶属函数模糊集,建立了D.C.隶属函数模糊集对模糊集的万有逼近性。探讨了D.C.隶属函数模糊集与模糊数之间的关系,给出了用D.C.隶属函数模糊集逼近模糊数的-εC e llina逼近形式,得到模糊数与D.C.函数之间的一个对应算子,指出了用模糊数表示D.C.函数的问题。     

凸体间的逼近

For the affine distance d(C, D) between two convex bodies C, D C R^n, which reduces to the Banach-Mazur distance for symmetric convex bodies, the bounds of d(C, D) have been studied for many years. Some well known estimates for the upper-bounds are as follows: F. John proved d(C, D) ≤ n^1/2 if one is an ellipsoid and another is symmetric, d(C, D) ≤ n if both are symmetric, and from F. John's result and d(C1, C2) ≤ d(C1, C3)d(C2, C3) one has d(C, D) ≤ n^2 for general convex bodies; M. Lassak proved d(C, D) ≤ (2n - 1) if one of them is symmetric. In this paper we get an estimate which includes all the results above as special cases and refines some of them in terms of measures of asvmmetrv for convex bodies.     

基于D-S证据理论的C2C交易风险评估模型

随着电子商务广泛展开,越来越多的用户选择C2C网上交易,但交易风险也不可忽视,对于普通用户来说,如何正确认识交易中的风险是确定选择该交易的重要依据.基于D-S证据理论的证据融合法,将C2C交易中的不确定性多级多指标评估问题转化为确定性单一总指标的风险评估问题,构建了一种比较通用的C2C交易风险评估模型.实例表明利用实践证明该方法是有效性的,可以为交易者提供参考.文中实例均来自淘宝网,但方法也适用于其它C2C交易平台,具有一定的应用价值.     

相似双曲线的一组优美性质

文[1]介绍了相似椭圆的一组性质,很容易把这些性质类推至双曲线.不仅如此,相似双曲线还具有更多的优美性质.为行文方便,本文约定双曲线C1的方程为ax22-by22=λ2(0<λ<1),双曲线C2的方程为xa22-by22=1.显然C1与C2相似,且相似比为λ.定理1过双曲线C2上任一点P引C2的切线l交双曲线C1于A,B两点.则|PA|=|PB|.定理2若直线l与双曲线C1交于A,B两点,与双曲线C2交于C,D两点,则|AC|=|BD|.以上性质的证明与文[1]完全类似,故略.定理3过原点的直线l1与双曲线C1,C2的右支分别交于点A1,A2.过原点的直线l2与双曲线C1,C2的右支分别交于点B1,B2.则…     

一道三角题解法的分析

<正>1.题目在△ABC中,A,B,C成等差数列.设t=sinAsinC,求t的最大值.2.解法分析由A,B,C成等差数列及A+B+C=π可得B=π/3,A+C=2π/3.分析一求最值,自然想到函数分析法,将两个自变量A,C利用A+C=2π/3减元,借助三角函数破解.     

用微积分求组合数的和

利用微积分解决有关组合数的和的问题,往往能使解题过程大为简化.现列举数例介绍如下:一、利用微分法求组合数的和例2.求证:C二+ZC二+3C君+…+。C盆 =”.2一1证,i’(1+x)“=C盒+C孟劣+C二xZ+C沈x“+…+C器义” 故两边对x求一导,得 。(1+劣)一‘=C二+ZC盖二+3C寻x“+…+nC;x”一‘. 令,=1,则得 C二+ZC盖+3C盒+…+。C器=。·2”一’. 例2.求证:C只一ZC毛+3C二一4C盒+…+(一1)”(n+l)C盆二O(凡>2).证’:二(1一x).=C马x一C盖戈“+C二到一C二x峪+…+(一1).C竺x“+1.故两边对二求导,得(l一劣)”一nx(1一劣)“一‘二C日一ZC二盒x+3C…     

基于合意空间的模糊子群

利用合意空间(ConsensusSpace)理论给出了一个群的C模糊子群的定义.指出这种模糊子群实际上是基于t范(Tm范)的模糊子群.证明了Rosenfeld的模糊子群是C模糊子群,且每一个C模糊子群都与一类特殊的C模糊子群同构.从而为模糊子群提供了新的理论基础.     

C(X) A上的自同构群

本文研究了连续函数代数C(X)与某个C*-代数 A的张量积C(X) A的自同构群.当 A是有单位元且具有平凡中心的C*-代数时,本文完全刻划了C(X) A的自同构群.利用AF-代数的K-理论,本文还刻划了当X是全不连通的紧致Hausdorff空间时,C(X)与紧算子理想的张量积的自同构群.     

半粘合诱导的t-结构（英文）

本文研究了对于给定的一个三角范畴的上(下)粘合(C′,C,C″),如何由C的一个t-结构诱导C′和C″的t-结构的问题.利用左(右)t-正合函子的概念,给出了由C的一个t-结构可诱导出C′和C″的t-结构的充分条件.将粘合的一些相关结果推广到了上(下)粘合的情形.     

Uniqueness and value-sharing of entire functions

In this paper, we study the uniqueness problems on entire functions sharing one value with the same multiplicities. We generalize and unify some previous results of Fang and Hua [M.L. Fang, X.H. Hua, Entire functions that share one value, J. Nanjing Univ. Math. Biquarterly 13 (1) (1996) 44-48], Yang and Hua [C.C. Yang, X.H. Hua, Uniqueness and value-sharing of meromorphic functions, Ann. Acad. Sci. Fenn. Math. 22 (2) (1997) 395-406] and Fang [M.L. Fang, Uniqueness and value-sharing of entire functions, Comput. Math. Appl. 44 (2002) 828-831].     

Uniqueness and value-sharing of differential polynomials of meromorphic functions

In this paper, we investigate uniqueness problems of meromorphic functions concerning differential polynomials sharing non-zero finite value and give some results. As particular cases of our results we deduce several earlier results of Fang and Hong (2001) [2], Fang and Hua (1996) [1], Lin and Yi (2004) [5], Yang and Hua (1997) [6] and others.     

亚纯函数的正规族

In this paper, we deal with the problem of normal families concerning share-values. The results extend and improve some theorems put forward by Miranda, Pang, Chen, Hua and Fang. Moreover, we answer one question posed by Gu, Pang, Fang and so on.     

整函数权分担一个值

This paper deals with some uniqueness problems of entire functions concerning differential polynomials that share one value with finite weight in a different form. We obtain some theorems which generalize some results given by Banerjee, Fang and Hua, Zhang and Lin, Zhang, etc.     

Uniqueness of entire functions sharing one value

We deal with the problem of entire functions sharing one value weakly. Moreover, we improve and generalize some former results obtained by J.-F.Chen, et al. [6], Y.Xu and H.L.Qiu [4], M.L. Fang [5], C.C. Yang, and X.H. Hua [3].     

UNIQUENESS OF MEROMORPHIC FUNCTIONS WHOSE NONLINEAR DIFFERENTIAL POLYNOMIALS SHARE ONE VALUE OR HAVE THE SAME FIXED POINTS IN AN ANGULAR DOMAIN

In this article, we study the uniqueness question of nonconstant meromorphic functions whose nonlinear differential polynomials share 1 or have the same fixed points in an angular domain. The results in this article improve Theorem 1 of Yang and Hua [26], and improve Theorem 1 of Fang and Qiu [6].     

Uniqueness of meromorphic functions whose nonlinear differential polynomials share one value or have the same fixed points in an angular domain

In this article, we study the uniqueness question of nonconstant meromorphic functions whose nonlinear differential polynomials share 1 or have the same fixed points in an angular domain. The results in this article improve Theorem 1 of Yang and Hua [26], and improve Theorem 1 of Fang and Qiu [6].     

Samuel multiplicity and the structure of essentially semi-regular operators: A note on a paper of Fang

Motivated by a paper of Fang (2009), we study the Samuel multiplicity and the structure of essentially semi-regular operators on an infinite-dimensional complex Banach space. First, we generalize Fang’s results concerning Samuel multiplicity from semi-Fredholm operators to essentially semi-regular operators by elementary methods in operator theory. Second, we study the structure of essentially semi-regular operators. More precisely, we present a revised version of Fang’s 4 × 4 upper triangular model with a little modification, and prove it in detail after providing numerous preliminary results, some of which are inspired by Fang’s paper. At last, as some applications, we get the structure of semi-Fredholm operators which revised Fang’s 4 × 4 upper triangular model, from a different viewpoint, and characterize a semi-regular point λ ∈ ? in an essentially semi-regular domain.     

Revisiting hua-marcus-bellman-ando inequalities on contractive matrices

Loo-Keng Hua showed some elegant matrix and determinant inequalities via a matrix identity and proved the positive semidefiniteness of a matrix involving the determinants of contractive matrices through group representation theory. His study was followed by M. Marcus, R. Bellman and T. Ando. The purpose of current paper is to revisit the Hua’s original work and the results of Marcus, Bellman and Ando with our comments, and to present analogs and extensions to their results.     

Weighted sharing three values and uniqueness of meromorphic functions

Using the idea of weighted sharing, we prove some results on uniqueness of meromorphic functions sharing three values which improve some results given by H.-X. Yi, I. Lahiri, X. Hua and other authors.