一类二变量积分不等式及其在积分-微分方程中的应用

建立了一类二变量的积分不等式,该不等式包含了一个一重积分和两个二重积分.利用分析技巧,给出了积分不等式中未知函数的估计.这一结果可以作为研究积分-微分方程解的定性性质的工具.     

一类含未知导函数p次幂的积分不等式中未知函数的估计

Gronwall-Bellman型积分不等式及其推广形式在研究微分方程、积分方程和微分-积分方程解的存在性、有界性、唯一性和稳定性等定性性质中有重要作用.研究了一类非线性积分不等式,被积函数中含有未知函数及其导函数的p次幂,积分项外有非常数因子和非常数项,利用变量替换技巧和放大技巧等分析手段,给出了积分-微分不等式中未知函数的上界估计,推广了已有结果.最后举例说明所得结果可以用来研究微分-积分方程解的定性性质.     

线性Volterra积分微分方程解的渐近性态

本文引进了一类新的微分积分不等式,应用所得不等式,得到了方程(1.1)的解趋于零(t→∞时)的充分条件。     

时标上的推广的Pachpatte型不等式及其在边值问题中的应用

该文利用单调化技巧研究了时标上的推广的Pachpatte型不等式, 该不等式右端有一个非常数项和三个包含未知函数与没有假设单调性的非线性函数的复合函数的积分项, 不等式左端是未知函数与非线性函数的复合函数. 所得不等式不仅把Pachpatte型不等式的离散形式和连续形式统一起来, 而且推广了已有的时标上的相应不等式. 最后, 用得到的结果研究时标上边值问题解的估计.     

一类新的非线性和差分不等式及其应用

由于差分不等式是研究差分方程解的存在性、有界性、唯一性、稳定性等定性性质的重要工具,许多数学家不仅研究Gronwall类积分不等式的各种推广形式及其应用,而且研究差分不等式及其应用.该文建立了一类新的非线性和差分不等式,利用分析技巧给出了不等式中未知函数的上界估计.将得到的结果应用到时滞差分方程的边值问题,得到了差分方程解的估计.     

一类非线性积分不等式组中未知函数的估计

研究了一类二维非线性积分不等式组,该不等式组积分号外有非常数因子,不能用向量形式的Gronwall-Bellman型积分不等式进行估计.先利用Bernoulli不等式把非线性问题转化成线性问题,利用变量替换技巧和放大技巧研究只含有一个未知函数的积分不等式,接着利用两个引理和变量替换技巧和放大技巧给出不等式组中两个未知函数的估计.结果可用于研究积分、微分动力系统解的性质.     

一类三变量非线性和差分不等式中未知函数的估计

Gronwall-Bellman型积分不等式的离散形式及其推广形式是研究和差分方程解的存在性、有界性和唯一性等定性性质的重要工具.研究了一类六重非线性和差分不等式,和号外含非常数因子,和项外包含了非常数项.利用差分算子的性质、求和技巧、变量替换技巧和积分中值定理等分析手段,给出了和差分不等式中未知函数的上界估计,推广了已有结果.最后举例说明所得结果可以用来研究三独立变量差分方程解的定性性质.     

一类非连续函数积分不等式中未知函数的估计及其应用

该文使用分析技巧和数学归纳法给出了一类非连续函数积分不等式中未知函数的估计.该文用所得结果研究文献[8]中的非连续函数不等式.最后,该文把所得结果用于研究脉冲积分-微分方程解的估计.     

一类二阶常微分方程及二阶微分差分方程的解的有界性

方程(c)是否存在有界解,文[1]尚未解决.本文将对此三种情形分别给出方程(1)的有界解的充分条件.得出的结果包括文[1]中相应的结果.在方法上,对较复杂的二阶非线性方程的解的有界性问题,使用积分不等式来解决是比较困难的,一般都是利用李雅普诺夫函数来导出充分条件,例如文[2,3]、都是如此.本文除用这种方法外,更着重的是探讨如何使用积分不等式来解决解的有界性问题.这是本文的主要目的.     

关于分布的 Gronwall-Bellman 型非线性积分不等式

<正> 近几年来 Gronwall-Bellman 型积分不等式在连续函数类中已得到了迅速的发展,它们在微分积分方程解的存在性、稳定性、唯一性、有界性等定性问题的研究中起着重要的作用.本文的目的是建立关于分布的 Gronwall-Bellman 型几种非线性积分不等式,从而推广了 V.Sree Hari Rao,U.D.Dhongade 及 S.G.Deo和 B.G.Pachpatter中的一些结果.值得提出的是本文所讨论的积分是 Lebesgue-Stieltjes 意义下的积分,而散见在各种有关文献中的 Gronwall-Bellman 型积分不等式都是在连续函数类中讨论的,其积分都是Riemann 意义下的积分,因此本文的结论更具有广泛性.作为应用,本文给出了两个具体的实例.     

Addendum to “Distribution of points on the circle” [J. Number Theory 127 (1) (2007) 127-135]

In an earlier paper we gave a result relating the value of an exponential sum with the distribution of summands in the arcs of the unit circle in the complex plane. In a marginal case, this result is superseded by a result of Lev. In this addendum we use an idea of Lev to give a new proof of our earlier result and to improve upon the marginal result.     

明目科研成果应用及其多元统计分析

本文简介了明目科研成果《易效明目功》的应用，并重点对易效明目功防治青少年近视的效用进行了多元统计分析，Ｐ＜０．０５，效果显著。     

A note on dentability, quasi-dentability and LUR renorming

In this work we prove a result that provides us an equivalent LUR norm in a normed space whenever it has the property of denting and compact faces in the unit ball; we obtain this result after applying the main result of [11]. In the last part of the paper we obtain our main result that gives us a universal map between dentability and quasi-dentability indices.Received: 29 July 2004; revised: 31 January 2005     

Conditions on subgraphs,degrees, and domination for hamiltonian properties of graphs

Motivated by a hamiltonicity result due to Ageev, involving claw-free graphs with a small domination number, we study analogous conditions that guarantee different types of hamiltonian properties. In our first main result we relax the condition on claw-freeness and obtain a common generalization of the result of Ageev and a recent result due to Cai. Our other results deal with similar conditions that guarantee traceability, pancyclicity and hamiltonian-connectivity. We also leave some open problems.     

An acceleration property of theE-algorithm for alternate sequences

We prove a convergence acceleration result by theE-algorithm for sequences whose error has an asymptotic expansion on the scale of comparison for which a determinantal relation holds. This result is generalized to the vector case. Moreover we prove a result which contains an acceleration property for columns and diagonals of theE array. This result is applied to some alternating series.     

Direct Result for a Summation-Integral Type Modification of Szász-Mirakjan Operators

In this paper, study of direct result for a summation-integral type modification of Szász-Mirakjan operators is carried out. Calculation of moments, density result and a Voronovskaja-type result are also obtained.     

Mazur-Ulam定理的一个注记

本文的主要结论是给出了一个更广泛形式的Mazur-Ulam定理.讨论的对象是实的赋准范空间,满等距算子被减弱成其像空间构成一个加法子群的算子.最后给出的推论推广了Skof的一个结果.     

Non-existence of positive solution to a quasilinear elliptic system and blow-up estimates for a reaction-diffusion system

IntroductionIn these years, the reaction-diffusion systems of Fujita typea5 ttell as the related elliptic systemt'ith fl g RN, Tnl. n1 3 0, i = 1, 2. \vere studied by' a nu111ber of authors. The probiemsconcerning system (l) inc1ude globa1 existence and g1obal existen(.e numbers. b1ow-up. bloxv-uprates, and blow-up sets. uniqueness or nonuniqueness. et('. FOr s}'stem (2) there are problemssuch as existence or non-existence. uniqueness or nonllniqueI1ess. and so ol1. 1Ieanwhile. itseems that…     

On Green’s functions for positive,elliptic differential operators on closed,Riemannian manifolds and some consequences for semi-linear PDE

In this article, we establish the non-negativity of Green’s functions for a class of elliptic differential operators on closed, Riemannian manifolds. The method used is the calculus of variations with a unilateral constraint. Consequences of this result are then explored, with a maximum principle-type result established for a broad class of semi-linear elliptic PDE as a result. Finally, a result regarding the positivity of the principal eigenfunction of an operator in this class is proven as well.     

Duality for Multiobjective Optimization via Nonlinear Lagrangian Functions

In this paper, a strong nonlinear Lagrangian duality result is established for an inequality constrained multiobjective optimization problem. This duality result improves and unifies existing strong nonlinear Lagrangian duality results in the literature. As a direct consequence, a strong nonlinear Lagrangian duality result for an inequality constrained scalar optimization problem is obtained. Also, a variant set of conditions is used to derive another version of the strong duality result via nonlinear Lagrangian for an inequality constrained multiobjective optimization problem.