C-Stieltjes积分和近似C-Stieltjes积分

定义了向量筐函数的C-Stieltjes近似可表示算子,并研究了它的性质。另外,我们定义了向量值函数的近似C-Stieltjes积分,并证明了它的收敛定理。     

一类奇异积分方程组的样条间接近似解法

本文利用三次复插值样条函数给了定义于复平面上光滑封闭曲线上的一类奇异积分方程组（１）的一种间接近似解法，讨论了误差估计和一致收敛性。     

多元弱奇异积分方程近似解直接方法的优化

本文研究了多元弱奇异第二类Ｆｒｅｄｈｏｌｍ积分方程数ψ在适应直接方法意义下的最优近似解产 们推广了文献「１」中的相关结果。     

Stokes型积分——微分方程的Galerkin近似

本文讨论一类具有Stokes方程结构的积分一微分方程的Galerkin近似，论证了近似解的存在唯一性，并分别导出速度和压力近似解的最优阶L_2模误差估计。     

带位移非线性奇异积分方程的离散近似解

将积分区间划分为2N 等分后,我们定义了带位移的离散奇异算子■~(N).对于广义 Hilder 空间 H_(α,β,γ)中的函数 u(x),被带位移奇异算子作用后与■(N)_u 的差在分点处是 O((ln N)/(Nγ)).算子■(N)是一致有界的。利用它,我们给出了一类带位移的非线性奇异积分(哥西核)方程的离散近似解     

近似连续C-可积函数的原函数刻画(英文)

本文研究了近似连续C-可积函数的原函数问题.利用近似连续C-积分的有关性质,得到了函数近似C-可积的一个充分必要条件,推广了B.Bongiorno等人的工作.     

AP积分与Gronwall不等式

ＡＰ积分与Ｇｒｏｎｗａｌｌ不等式王才士（西北师范大学计算机系，兰州７３００７０）设表示实直线Ｒ上的密度拓扑（见［２］）．点ｘ∈Ｒ在密度拓扑下的邻域系记为定义称函数ｆ在［ａ，ｂ］上满足Ａ－Ｎ条件，如果对任何非空零测集及任意ε＞０，存在的一个选择使得对［...     

一类非线性奇异积分方程的离散近似解及其误差估计

当函数f(x,t,u)满足一些[1]中常假定的条件时,我们可借助算子S~(N)和不等式证明非线性奇异积分方程有唯一的离散近似解,这个解可用关于距离的逐次逼近法得到.     

开口曲线上的奇异积分近似求积公式

本文利用复插值样函数讨论了开口光滑曲线上的奇异积分在被积函数分别属于 H类和 H* 类时的近似求积公式 ,给出了误差估计和收敛性     

求时滞Volterra积分系统最优控制问题近似解的一个迭代算法

对一类典型的复杂系统—含多个非线性时滞的Volterra积分系统,给出其控制作用受限(硬约束)最优控制问题近似解的一个迭代算法,证明了该算法是well-defined的,并在一定的条件下证得了算法的收敛性.     

A generalization of the denjoy integral

We prove that the IsekiM-integral is substantially more general than the Denjoy integral. Translated fromMatematicheskie Zametki, Vol. 62, No. 5, pp. 766–772, November, 1997. Translated by I. P. Zvyagin     

Approximately unital operator systems

The main theme of this paper is to consider a notion of 'approximately unital operator systems' including both C*-algebras and unital operator systems.The goals are to prove a version of the Choi-Effros theorem for these systems,to introduce a functorial process for forming an approximately unital operator systems from a given matrix ordered vector space with a proper approximate order unit,to study second duals of these objects and to prove that a C*-algebra can be characterized as an approximately unital ...     

The generalized approximate Perron integral

In this paper we introduce the concept of the generalized AP-integral and discuss the properties of this integral.      

The widest continuous integral

An approach to a definition of an integral, which differs from definitions of Lebesgue and Henstock-Kurzweil integrals, is considered. We use trigonometrical polynomials instead of simple functions. Let V be the space of all complex trigonometrical polynomials without the free term. The definition of a continuous integral on the space V is introduced. All continuous integrals are described in terms of norms on V. The existence of the widest continuous integral is proved, the explicit form of its norm is obtained and it is proved that this norm is equivalent to the Alexiewicz norm. It is shown that the widest continuous integral is wider than the Lebesgue integral. An analog of the fundamental theorem of calculus for the widest continuous integral is given.     

Symmetrically approximately continuous functions, consistent density theorems, and Fubini type inequalities

Using the continuum hypothesis, Sierpinski constructed a nonmeasurable function such that is countable for every Clearly, such a function is symmetrically approximately continuous everywhere.

Here we to show that Sierpinski's example cannot be constructed in ZFC. Moreover, we show it is consistent with ZFC that if a function is symmetrically approximately continuous almost everywhere, then it is measurable.

     

二维Fredholm方程的Taylor展开式解法

本文讨论了一类二维Fredholm方程的一种近拟解,通过利用二元函数的Taylor展开式,积分方程转化成一个关于未知函数及其相应的偏导数的线性代数方程组.数值例子表明了该方法的有效性.     

PQWs in complex plane: Application to Fredholm integral equations

In this paper, we use a numerical procedure for solving Fredholm integral equations of the second kind in complex plane. The periodic quasi-wavelets (PQWs) constructed on [0,2π]$[0\text{,}2\pi ]$ are utilized as a basis in collocation method to reduce the solution of linear integral equations to a system of algebraic equations. Convergence analysis is derived and we used some numerical examples to illustrate the accuracy and the implementation of the method.     

A constructive integral equivalent to the integral of Kurzweil

We slightly modify the definition of the Kurzweil integral and prove that it still gives the same integral.