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On the Variational Problems of the Functionals with Derivatives of Higher Orders and Undetermined Boundary 被引量:1
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作者 老大中 谈天民 《Journal of Beijing Institute of Technology》 EI CAS 2007年第1期116-121,共6页
According to the necessary condition of the functional taking the extremum, that is its first variation is equal to zero, the variational problems of the functionals for the undetermined boundary in the calculus of va... According to the necessary condition of the functional taking the extremum, that is its first variation is equal to zero, the variational problems of the functionals for the undetermined boundary in the calculus of variations are researched, the functionals depend on single argument, arbitrary unknown functions and their derivatives of higher orders. A new view point is posed and demonstrated, i.e. when the first variation of the functional is equal to zero, all the variational terms are not independent to each other, and at least one of them is equal to zero. Some theorems and corollaries of the variational problems of the functionals are obtained. 展开更多
关键词 calculus of variations functionAL variational problems derivatives of higher orders undetermined boundary
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A NOTE ON MEYER-KONIG AND ZELLER OPERATORS FOR FUNCTIONS OF BOUNDED VARIATION 被引量:2
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作者 Vijay Gupta (Netaji Subhas Institute of Technology, India) 《Approximation Theory and Its Applications》 2002年第3期99-102,共4页
In the present note we give the correct and improved estimate on the rate of convergence of integrated Meyer-Konig and Zetter operators for function of bounded variation.
关键词 RATE In MATH A NOTE ON MEYER-KONIG AND ZELLER OPERATORS FOR functionS OF bounded variation
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A SHARP ESTIMATE ON THE DEGREE OF APPROXIMATION TO FUNCTIONS OF BOUNDED VARIATION BY CERTAIN OPERATORS 被引量:1
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作者 Vijay Gupta 《Analysis in Theory and Applications》 1995年第3期106-107,共2页
Recently Guo introduced integrated Meyer -Konig and Zeller operators and studied the rate of convergence for function of bounded variation. In this note we give a sharp estimate for these operators.
关键词 A SHARP ESTIMATE ON THE DEGREE OF APPROXIMATION TO functionS OF bounded variation BY CERTAIN OPERATORS
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Nemytskii Operator in the Space of Set-Valued Functions of Bounded <i>φ</i>-Variation
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作者 Wadie Aziz 《Advances in Pure Mathematics》 2013年第6期563-575,共13页
In this paper we consider the Nemytskii operator, i.e., the composition operator defined by (Nf)(t)=H(t,f(t)), where H is a given set-valued function. It is shown that if the operator N maps the space of functions bou... In this paper we consider the Nemytskii operator, i.e., the composition operator defined by (Nf)(t)=H(t,f(t)), where H is a given set-valued function. It is shown that if the operator N maps the space of functions bounded φ1-variation in the sense of Riesz with respect to the weight function αinto the space of set-valued functions of bounded φ2-variation in the sense of Riesz with respect to the weight, if it is globally Lipschitzian, then it has to be of the form (Nf)(t)=A(t)f(t)+B(t), where A(t) is a linear continuous set-valued function and B is a set-valued function of bounded φ2-variation in the sense of Riesz with respect to the weight. 展开更多
关键词 bounded variation function of bounded variation in the Sense of Riesz variation SPACE Weight function Banach SPACE Algebra SPACE
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Some Results on the Space of Bounded Second Variation Functions in the Sense of Shiba
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作者 Liliana Pérez Ebner Pineda Luz Rodríguez 《Advances in Pure Mathematics》 2020年第5期245-258,共14页
In this paper, we study the structure of the space of functions of bounded second variation in the sense of Shiba;an integral representation theorem is also proved and necessary conditions are given for that the space... In this paper, we study the structure of the space of functions of bounded second variation in the sense of Shiba;an integral representation theorem is also proved and necessary conditions are given for that the space be closed under composition of functions. Another significant result is the proof that this space of bounded second variation in the sense of Shiba is a Banach algebra, which is not immediate as it happens in other spaces of generalized bounded variation. 展开更多
关键词 functional Analysis bounded variation SECOND bounded variation BANACH SPACE
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Uniformly Bounded Set-Valued Composition Operators in the Spaces of Functions of Bounded Variation in the Sense of Riesz
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作者 Wadie Aziz Nelson Merentes 《International Journal of Modern Nonlinear Theory and Application》 2015年第4期226-233,共8页
We show that the lateral regularizations of the generator of any uniformly bounded set-valued composition Nemytskij operator acting in the spaces of functions of bounded variation in the sense of Riesz, with nonempty ... We show that the lateral regularizations of the generator of any uniformly bounded set-valued composition Nemytskij operator acting in the spaces of functions of bounded variation in the sense of Riesz, with nonempty bounded closed and convex values, are an affine function. 展开更多
关键词 j-variation in the SENSE of RIESZ SET-VALUED functions Left and Right Regularizations UNIFORMLY bounded OPERATOR Composition (Nemytskij) OPERATOR Jensen Equation
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Complements to the Theory of Higher-Order Types of Asymptotic Variation for Differentiable Functions 被引量:1
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作者 Antonio Granata 《Advances in Pure Mathematics》 2019年第5期434-479,共46页
The purpose of this paper is to add some complements to the general theory of higher-order types of asymptotic variation developed in two previous papers so as to complete our elementary (but not too much!) theory in ... The purpose of this paper is to add some complements to the general theory of higher-order types of asymptotic variation developed in two previous papers so as to complete our elementary (but not too much!) theory in view of applications to the theory of finite asymptotic expansions in the real domain, the asymptotic study of ordinary differential equations and the like. The main results concern: 1) a detailed study of the types of asymptotic variation of an infinite series so extending the results known for the sole power series;2) the type of asymptotic variation of a Wronskian completing the many already-published results on the asymptotic behaviors of Wronskians;3) a comparison between the two main standard approaches to the concept of “type of asymptotic variation”: via an asymptotic differential equation or an asymptotic functional equation;4) a discussion about the simple concept of logarithmic variation making explicit and completing the results which, in the literature, are hidden in a quite-complicated general theory. 展开更多
关键词 HIGHER-order Regularly-Varying functionS HIGHER-order Rapidly-Varying functionS Smoothly-Varying functionS Exponentially-Varying functionS Logarithmically-Varying functionS ASYMPTOTIC Differential EQUATIONS As-ymptotic functional EQUATIONS ASYMPTOTIC variation of Wronskians
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Generalized gap functions and error bounds for generalized variational inequalities
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作者 胡艳红 宋文 Xie-ping DING 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第3期313-321,共9页
We consider some classes of generalized gap functions for two kinds of generalized variational inequality problems. We obtain error bounds for the underlying variational inequalities using the generalized gap function... We consider some classes of generalized gap functions for two kinds of generalized variational inequality problems. We obtain error bounds for the underlying variational inequalities using the generalized gap functions under the condition that the involved mapping F is g-strongly monotone with respect to the solution, but not necessarily continuous differentiable, even not locally Lipschitz. 展开更多
关键词 variational inequality gap functions error bounds
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Gap Functions and Error Bounds for Set-Valued Vector Quasi Variational Inequality Problems
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作者 Rachana Gupta Aparna Mehra 《Applied Mathematics》 2017年第12期1903-1917,共15页
One of the classical approaches in the analysis of a variational inequality problem is to transform it into an equivalent optimization problem via the notion of gap function. The gap functions are useful tools in deri... One of the classical approaches in the analysis of a variational inequality problem is to transform it into an equivalent optimization problem via the notion of gap function. The gap functions are useful tools in deriving the error bounds which provide an estimated distance between a specific point and the exact solution of variational inequality problem. In this paper, we follow a similar approach for set-valued vector quasi variational inequality problems and define the gap functions based on scalarization scheme as well as the one with no scalar parameter. The error bounds results are obtained under fixed point symmetric and locally α-Holder assumptions on the set-valued map describing the domain of solution space of a set-valued vector quasi variational inequality problem. 展开更多
关键词 SET-VALUED VECTOR QUASI variational Inequality Problem GAP function Regularized GAP function Error bounds Fixed Point Symmetric MAP α-Holder MAP
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On Bounded Second Variation
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作者 José Giménez Lorena López +1 位作者 N. Merentes J. L. Sánchez 《Advances in Pure Mathematics》 2012年第1期22-26,共5页
In this paper, we discuss various aspects of the problem of space-invariance, under compositions, of certain subclasses of the space of all continuously differentiable functions on an interval [a,b] We present a resul... In this paper, we discuss various aspects of the problem of space-invariance, under compositions, of certain subclasses of the space of all continuously differentiable functions on an interval [a,b] We present a result about integrability of products of the form gοf.f'f(k)under suitable mild conditions and, finally, we prove that a Nemytskij operator Sg maps BV''[a,b] a distinguished subspace of the space of all functions of second bounded variation, into itself if, and only if, g BV''loc(R) A similar result is obtained for the space of all functions of bounded (p,2)-variation (1≤p≤1), 展开更多
关键词 function of bounded variation LIPSCHITZ CONTINUOUS function Absolutely CONTINUOUS function Nemytskij OPERATOR
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MEROMORPHIC FUNCTIONS WITH BOUNDED BOUNDARY ROTATION
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作者 Jacek DZIOK 《Acta Mathematica Scientia》 SCIE CSCD 2014年第2期466-472,共7页
In this article, we generalize the class of meromorphic functions with bounded boundary rotation and related classes. Characterizations and some properties of these classes of functions are given.
关键词 Meromorphic functions bounded variation bounded boundary rotation
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On a subclass of bi-univalent functions defined by convex combination of order α with the Faber polynomial expansion
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作者 Wurenqiqige LI Shu-hai Tsedenbayar Dashdondog 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2021年第2期278-286,共9页
In this paper,we define new subclasses of bi-univalent functions involving a differ-ential operator in the open unit disc△={z:z∈C and|z|<1}:Moreover,we use the Faber polynomial expansion to obtain the bounds of t... In this paper,we define new subclasses of bi-univalent functions involving a differ-ential operator in the open unit disc△={z:z∈C and|z|<1}:Moreover,we use the Faber polynomial expansion to obtain the bounds of the coefficients for functions belong to the subclasses. 展开更多
关键词 bi-univalent functions convex combination Faber polynomial expansion coefficient bounds su bordination combination of orderα
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基于二次分数低阶协方差的时延估计方法 被引量:1
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作者 刘小松 徐再祥 +2 位作者 单泽彪 徐恩达 吕悦 《电子测量与仪器学报》 CSCD 北大核心 2024年第2期112-119,共8页
针对强脉冲噪声背景下基于分数低阶统计量时延估计方法性能退化且需要噪声先验知识的问题,提出了一种基于二次分数低阶协方差的时延估计新方法。所提方法首先利用有界非线性Sigmoid函数对含有脉冲噪声的信号进行预处理,使其在不影响有... 针对强脉冲噪声背景下基于分数低阶统计量时延估计方法性能退化且需要噪声先验知识的问题,提出了一种基于二次分数低阶协方差的时延估计新方法。所提方法首先利用有界非线性Sigmoid函数对含有脉冲噪声的信号进行预处理,使其在不影响有用信号时延信息的基础上对附加脉冲噪声进行充分压缩;然后对处理后的收发信号进行二次分数低阶协方差运算,即求得发射信号的自分数低阶协方差和收发信号的互分数低阶协方差之后,再次计算二者的互分数低阶协方差,以期更大程度上抑制脉冲噪声的影响。通过模拟仿真实验对所提方法进行了有效性验证,结果表明所提方法突破了分数低阶矩阶次需小于Alpha稳定分布噪声特征指数的限制,并且比分数低阶协方差方法具有更高的估计精度。仿真实验结果表明在广义信噪比-10 dB情况下,时延估计用时为0.0560 s,准确率达到97.76%。 展开更多
关键词 时延估计 脉冲噪声 二次分数低阶协方差 有界非线性函数
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On Bounded Variation Functions by General MKZD Operators
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作者 Vijay GUPTA 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2007年第8期1457-1462,共6页
In this paper, we study the rate of convergence for functions of bounded variation for the recently introduced Bzier variant of the Meyer-Knig-Zeller-Durrmeyer operators.
关键词 approximation by positive operators rate of convergence degree of approximation functions of bounded variation total variation
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基于加权有界形变函数的可形变图像配准模型
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作者 闵莉花 丁田中 金正猛 《计算机科学》 CSCD 北大核心 2024年第6期206-214,共9页
可形变图像配准是图像处理领域中一个非常重要的课题,是计算机视觉中最基本的问题之一,也是医学图像分析的一个难题。文中研究了两幅单模态灰度图像之间的图像配准问题,充分考虑了参考图像的边缘信息,提出了一个新的基于加权有界形变函... 可形变图像配准是图像处理领域中一个非常重要的课题,是计算机视觉中最基本的问题之一,也是医学图像分析的一个难题。文中研究了两幅单模态灰度图像之间的图像配准问题,充分考虑了参考图像的边缘信息,提出了一个新的基于加权有界形变函数的可形变图像配准模型。首次提出了加权的有界形变函数空间,给出了该空间的定义及相关结论,并从理论上证明了所提模型解的存在性。同时,利用梯度下降法设计了有效的算法进行数值求解,分别在合成图像和医学图像上进行数值实验。实验结果和定量评估结果表明,与对比模型相比,所提模型由于引入了控制函数且将加权有界形变函数作为正则项,得到了更精确的配准结果,特别是在图像边缘及一些细节处配准效果有明显提高。 展开更多
关键词 可形变图像配准 加权有界形变函数 变分方法 梯度下降法
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Subspaces for weak mild solutions of the second order abstract differential equation
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作者 王梅英 《Journal of Southeast University(English Edition)》 EI CAS 2007年第2期313-316,共4页
The topic on the subspaces for the polynomially or exponentially bounded weak mild solutions of the following abstract Cauchy problem d^2/(dr^2)u(t,x)=Au(t,x);u(0,x)=x,d/(dt)u(0,x)=0,x∈X is studied, wher... The topic on the subspaces for the polynomially or exponentially bounded weak mild solutions of the following abstract Cauchy problem d^2/(dr^2)u(t,x)=Au(t,x);u(0,x)=x,d/(dt)u(0,x)=0,x∈X is studied, where A is a closed operator on Banach space X. The case that the problem is ill-posed is treated, and two subspaces Y(A, k) and H(A, ω) are introduced. Y(A, k) is the set of all x in X for which the second order abstract differential equation has a weak mild solution v( t, x) such that ess sup{(1+t)^-k|d/(dt)〈v(t,x),x^*〉|:t≥0,x^*∈X^*,|x^*‖≤1}〈+∞. H(A, ω) is the set of all x in X for which the second order abstract differential equation has a weak mild solution v(t,x)such that ess sup{e^-ωl|d/(dt)〈v(t,x),x^*)|:t≥0,x^*∈X^*,‖x^*‖≤1}〈+∞. The following conclusions are proved that Y(A, k) and H(A, ω) are Banach spaces, and both are continuously embedded in X; the restriction operator A | Y(A,k) generates a once-integrated cosine operator family { C(t) }t≥0 such that limh→0+^-1/h‖C(t+h)-C(t)‖Y(A,k)≤M(1+t)^k,arbitary t≥0; the restriction operator A |H(A,ω) generates a once- integrated cosine operator family {C(t)}t≥0 such that limh→0+^-1/h‖C(t+h)-C(t)‖H(A,ω)≤≤Me^ωt,arbitary t≥0. 展开更多
关键词 second order abstract differential equation polynomially bounded solution cosine operator function
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An Identity for Expectations and Characteristic Function of Matrix Variate Skew-normal Distribution with Applications to Associated Stochastic Orderings
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作者 Tong Pu Narayanaswamy Balakrishnan Chuancun Yin 《Communications in Mathematics and Statistics》 SCIE CSCD 2023年第3期629-647,共19页
We establish an identity for E f(Y)-E f(X),when X and Y both have matrix variate skew-normal distributions and the function f satisfies some weak conditions.The characteristic function of matrix variate skew normal dis... We establish an identity for E f(Y)-E f(X),when X and Y both have matrix variate skew-normal distributions and the function f satisfies some weak conditions.The characteristic function of matrix variate skew normal distribution is then derived.We then make use of it to derive some necessary and sufficient conditions for the comparison of matrix variate skew-normal distributions under six different orders,such as usual stochastic order,convex order,increasing convex order,upper orthant order,directionally convex order and supermodular order. 展开更多
关键词 Characteristic function Integral order Matrix variate skew-normal distributions Stochastic comparisons
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基于Pochhammer k符号的Lupaş-Beta算子逼近性质
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作者 程文韬 刘玉洁 +1 位作者 杨瑞 华义平 《安庆师范大学学报(自然科学版)》 2024年第1期24-29,共6页
参数型基函数曲线曲面造型的应用与相应算子的结构性质和收敛性质被广泛关注。为此,本文首次利用Beta函数,构造了一种基于Pochhammer k符号的Lupas-Beta含幂参数型算子。同时,利用中心矩研究了该算子的Voronovskaya型渐进公式,根据Ditzi... 参数型基函数曲线曲面造型的应用与相应算子的结构性质和收敛性质被广泛关注。为此,本文首次利用Beta函数,构造了一种基于Pochhammer k符号的Lupas-Beta含幂参数型算子。同时,利用中心矩研究了该算子的Voronovskaya型渐进公式,根据Ditzian-Totik光滑模和Peetre’-K泛函讨论了其全局逼近,并借助函数的分解技巧和区间分割技术等研究了其关于导数为有界变差函数的点态估计。本研究将为该算子在曲线曲面造型中的应用提供关键的理论依据。 展开更多
关键词 Lupas-Beta算子 Pochhammer k符号 全局逼近 有界变差函数
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EXTENSION OF SOLUTIONS TO RIEMANN BOUNDARY VALUE PROBLEMS AND ITS APPLICATION 被引量:2
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作者 路见可 《Acta Mathematica Scientia》 SCIE CSCD 2007年第4期694-702,共9页
In this paper, solutions of Riemann boundary value problems with nodes are extended to the case where they may have singularties of high order at the nodes. Moreover, further extension is discussed when the free term ... In this paper, solutions of Riemann boundary value problems with nodes are extended to the case where they may have singularties of high order at the nodes. Moreover, further extension is discussed when the free term of the problem involved also possesses singularities at the nodes. As an application, certain singular integral equation is discussed. 展开更多
关键词 Riemann boundary value problem class KN index and canonical function in class KN almost bounded almost of order k characteristic singular integral equation
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Muntz Rational Approximation for Special Function Classes in Orlicz Spaces 被引量:1
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作者 Ruifang Yu Garide Wu 《Analysis in Theory and Applications》 CSCD 2017年第1期20-28,共9页
Using the method of construction, with the help of inequalities, we research the Muntz rational approximation of two kinds of special function classes, and give the corresponding estimates of approximation rates of th... Using the method of construction, with the help of inequalities, we research the Muntz rational approximation of two kinds of special function classes, and give the corresponding estimates of approximation rates of these classes under widely con- ditions. Because of the Orlicz Spaces is bigger than continuous function space and the Lp space, so the results of this paper has a certain expansion significance. 展开更多
关键词 Muntz rational approximation bounded variation function class Sobolev functionclass Orlicz space.
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