均值有界变差条件及其在Fourier分析中的应用

本文宣布了关于Fourier (三角)级数的系数数列单调性条件的一个最终推广.我们已经证明了该条件对正弦级数保持一致收敛性方面已不可作任何推广,一些Fourier分析中重要和有趣的经典定理也已经在此最终条件下重新建立.本文因而对长达90年的研究历史作了一个简要综述.这一系列论文中的第一篇原始论文公布在arXiv:math.CA/0611805 v1, November 27, 2006.     

Perturbed Differential Inclusion Problems with Nonadditive L 1-Perturbations and Applications

A modification to a theorem in Ref. 1 and its proof are given.     

Perturbed Differential Inclusion Problems with Nonadditive L 1-Perturbations and Applications

In this paper, we derive an estimate for the G-subderivative of the value function associated with a perturbed optimization problem with differential inclusion constraints. We then apply this result to obtain a necessary condition for a solution to a bilevel dynamic problem.     

Box Dimension of Weyl Fractional Integral of Continuous Functions with Bounded Variation

We know that the Box dimension of f(x) ∈ C~1[0,1] is 1. In this paper, we prove that the Box dimension of continuous functions with bounded variation is still1. Furthermore, Box dimension of Weyl fractional integral of above function is also 1.     

Measures with Bounded Variation with Respect to a Normed Ideal of Operators and Applications

We introduce in a natural way the notion of measure with bounded variation with respect to a normed ideal of operators and prove that for each maximal normed ideal of operators (, ), is true the following result: If U ∈ L(C(T,X), Y) with G the representing measure of U and G : Σ → ((X, Y),) has bounded variation, then U ∈ (C(T,X), Y). As an application of this result we prove that an injective tensor product of an integral operator with an operator belonging to a maximal normed ideal of operators (,) belongs also to (, ).     

Regularization by Functions of Bounded Variation and Applications to Image Enhancement

Optimization problems regularized by bounded variation seminorms are analyzed. The optimality system is obtained and finite-dimensional approximations of bounded variation function spaces as well as of the optimization problems are studied. It is demonstrated that the choice of the vector norm in the definition of the bounded variation seminorm is of special importance for approximating subspaces consisting of piecewise constant functions. Algorithms based on a primal—dual framework that exploit the structure of these nondifferentiable optimization problems are proposed. Numerical examples are given for denoising of blocky images with very high noise. Accepted 29 March 1998     

Bounded Variation Spaces with p-Variable

In this paper, we introduce bounded variation spaces in the Wiener sense with p-variable and study some of its basic properties.     

不连续系统有界变差解对参数的连续依赖性

利用Henstock积分，讨论了一类不连续系统有界变差解对参数的连续依赖性及其它相关性质．     

Rate Conservation Laws for Multidimensional Processes of Bounded Variation with Applications to Priority Queueing Systems

In this paper we derive a multidimensional version of the rate conservation law (RCL) for càdlàg processes of bounded variation. These results are then used to analyze queueing models which have a natural multidimensional characterization, such as priority queues. In particular the RCL is used to establish certain conservation laws between the idle probabilities for such queues. We use the relations to provide a detailed analysis of preemptive resume priority queues with M/G inputs. Special attention is paid to the validity of the so-called reduced service rate approximation.     

一类分数阶非线性时滞问题的奇摄动

讨论了一类奇异摄动非线性分数阶时滞问题.首先利用奇异摄动方法求出了问题的外部解.再利用伸展变量法构造了问题在边界附近的两个边界层校正项,得出了所提问题的形式渐近解.最后,在合适的假设条件下,利用微分不等式理论证明了解的一致有效性,并给出了结论及未来的研究方向.     

具有分段有界变差系数的三角级数

通过引入所称谓的分段有界变差数列(PBVS),将关于具有非负系数的三角级数的收敛性和可积性的经典结果推广到具有可变系数(允许变号)的三角级数.     

指数型二分性与拟自治奇异摄动系统

通过对Ｋ．Ｊ．Ｐａｌｍｅｒ￣［４］中方法的改进，本文讨论了摄动系统有界解的存在性，得到了不同于［４］中的结果，并把改进了的方法运用到拟自治奇异摄动系统，得到了拟自治奇异摄动系统存在有界解的一个简洁的充分条件。本文的方法还提供了一个处理摄动项含小参数的方法。     

KKT Optimality Conditions and Nonsmooth Continuous Time Optimization Problems

We introduce a concept of generalized invexity for the nonsmooth continuous time optimization problems, namely, the concept of Karush-Kuhn-Tucker (KKT) invexity. Then, we prove that this notion is necessary and sufficient for global optimality of a KKT point. We also extend the notion of weak-invexity for nonsmooth continuous time optimization problems. Further, we show that weak-invexity is a necessary and sufficient condition for weak duality.     

Slow Evolution in Perturbed Hamiltonian Systems

For parametrized Hamiltonian systems with an arbitrary, finite number of degrees of freedom, it is shown that secularly stable families of equilibrium solutions represent approximate trajectories for small (not necessarily Hamiltonian) perturbations of the original system. This basic result is further generalized to certain conservative, but not necessarily Hamiltonian, systems of differential equations. It generalizes to the conservative case a theorem due, in the dissipative case, to Tikhonov, to Gradshtein, and to Levin and Levinson. It justifies the use of physically motivated approximation procedures without invoking the method of averaging and without requiring nonresonance conditions or the integrability of the unperturbed Hamiltonian.     

有界闭区间上连续函数的平均值问题的良定性

给出了函数的平均值问题的良定性概念,并证明了有界闭区间上连续函数的平均值问题是G-wp和GLP-wp的等结论.     

On Uniform Approximation in R2 of Continuous Functions of Two Variables with Bounded Variation in the Sense of Hardy

Introduce the notation: $\mathbb{Z}$ is the set of integers, $\bar {\mathbb{Z}}={\mathbb{Z}} \cup \{-\infty, +\infty\},{\mathbb{R}}_+^2 =\{x=(x_1,x_2) \in {\mathbb{R}}^2; x_1>0,x_2>0\}$ , $g_{k,m} (x,\alpha,h)= \int\limits_0^1 {g_1 (\frac{(k+u)h_1 - x_1}{\alpha_1})g_2(\frac{(m+u)h_2 - x_2}{\alpha_2})}du$ , where $g_i :\mathbb{R} \to \mathbb{R},x \in \mathbb{R}^2 ,\alpha ,h \in \mathbb{R}_ + ^2 $ . Under certain conditions on the functions g ₁, g ₂, we prove that the system of functions $g_{k,m} (x,\alpha^(n), h^(n)) (k,m \in \bar {\mathbb{Z}})$ , where $\alpha ^{\left( n \right)} ,h^{\left( n \right)} \in \mathbb{R}_ + ^2 $ are arbitrary infinitesimal sequences, is complete in the space C $\mathbb{R}^2 $ of uniformly continuous bounded functions f equipped with the norm $||f|| = \mathop {\sup }\limits_{x \in \mathbb{R}^2 } |f(x)|$ . Starting with the functions g _k,m , it is possible to construct a method for uniform approximating in $\mathbb{R}^2 $ any continuous function of bounded variation in the sense of Hardy. An error estimate is derived in terms of the second order moduli of continuity. Based on the obtained results, we discuss in detail the accuracy of uniform approximation of functions of several variables by linear functions. The error estimates are derived by using second order moduli of continuity. We pay a particular attention to sharpness of constants. Bibliography: 8 titles.     

Singularly Perturbed Parabolic Problems with Multidimensional Boundary Layers

The first boundary value problem for a multidimensional parabolic differential equation with a small parameter ε multiplying all derivatives is studied. A complete (i.e., of any order with respect to the parameter) regularized asymptotics of the solution is constructed, which contains a multidimensional boundary layer function that is bounded for x = (x¹, x₂) = 0 and tends to zero as ε → +0 for x ≠ 0. In addition, it contains corner boundary layer functions described by the product of a boundary layer function of the exponential type by a multidimensional parabolic boundary layer function.