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WEIGHTED APPROXIMATION OF RANDOM FUNCTIONS
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作者 YU JIARONG 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1995年第4期361-366,共6页
Let (Ω, A, P) be a probability space, X(t, ω) a random function continuous in probability for t∈[0,+∞) or (-∞,+∞)(ω∈Ω), and F(t) a positive function continuous for t∈[0,+∞) or (-∞, +∞). If X(t, ω) and F(... Let (Ω, A, P) be a probability space, X(t, ω) a random function continuous in probability for t∈[0,+∞) or (-∞,+∞)(ω∈Ω), and F(t) a positive function continuous for t∈[0,+∞) or (-∞, +∞). If X(t, ω) and F(t) verify certain conditions, then there exists a sequence {Qn(t,ω)} of random polynomials such that we have almost surely: for t∈[0,+∞) or (-∞, +∞), lim|X(t, ω)-Qn(t, ω)|/F(t)=0. 展开更多
关键词 Random function continuous in probability weighted approximation.
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Weighted approximation of functions with singularities by Bernstein operators 被引量:8
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作者 Bao-rong WEI Yi ZHAO 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第10期1451-1456,共6页
As an important type of polynomial approximation, approximation of functions by Bernstein operators is an important topic in approximation theory and computational theory. This paper gives global and pointwise estimat... As an important type of polynomial approximation, approximation of functions by Bernstein operators is an important topic in approximation theory and computational theory. This paper gives global and pointwise estimates for weighted approximation of functions with singularities by Bernstein operators. The main results are the Jackson's estimates of functions f∈ (Wwλ)2 andre Cw, which extends the result of (Della Vecchia et al., 2004). 展开更多
关键词 Bemstein operators Functions with singularities weighted approximation Pointwise estimates
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WEIGHTED INEQUALITIES AND APPLICATIONS TO BEST LOCAL APPROXIMATION IN LUXEMBURG NORM 被引量:2
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作者 H.H.Cuenya M.D.Lorenzo C.N.Rodriguez 《Analysis in Theory and Applications》 2004年第3期265-280,共16页
In this paper we establish a result about uniformly equivalent norms and the convergence of best approximant pairs on the unitary ball for a family of weighted Luxemburg norms with normalized weight functions dependin... In this paper we establish a result about uniformly equivalent norms and the convergence of best approximant pairs on the unitary ball for a family of weighted Luxemburg norms with normalized weight functions depending on ε, when ε→ 0. It is introduced a general concept of Pade approximant and we study its relation with the best local quasi-rational approximant. We characterize the limit of the error for polynomial approximation. We also obtain a new condition over a weight function in order to obtain inequalities in Lp norm, which play an important role in problems of weighted best local Lp approximation in several variables. 展开更多
关键词 weighted Luxemburg norm best local aproximation Fade approximant
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On Weighted L^p-Approximation by Weighted Bernstein-Durrmeyer Operators 被引量:2
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作者 Meiling Wang Dansheng Yu Dejun Zhao 《Analysis in Theory and Applications》 CSCD 2018年第1期1-16,共16页
In the present paper, we establish direct and converse theorems for weight-ed Bernstein-Durrmeyer operators under weighted L^p-norm with Jacobi weight w(x)=x^a(1-x)β.All the results involved have no restriction a... In the present paper, we establish direct and converse theorems for weight-ed Bernstein-Durrmeyer operators under weighted L^p-norm with Jacobi weight w(x)=x^a(1-x)β.All the results involved have no restriction a,β〈1-1/p,which indicates that the weighted Bemstein-Durrmeyer operators have some better approxi- mation properties than the usual Bernstein-Durrmeyer operators. 展开更多
关键词 weighted Lp-approximation weighted Bernstein-Durrmeyer operators direct andconverse theorems.
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ON WEIGHTED L^p INTEGRABILITY AND APPROXIMATION OF TRIGONOMETRIC SERIES 被引量:1
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作者 Baorong Wei and Dansheng Yu Department of Mathematics Hangzhou Normal University Hangzhou, 310036P. R. China Department of Mathematics Hangzhou Normal University Hangzhou, 310036 P. R. China and Department of Mathematics Statistics and Computer Sciences St Franics Xaiver University Antigonish, Nova ScotiaCanada B2G 2w5 《Analysis in Theory and Applications》 2009年第1期40-54,共15页
We generalize several classical results on the integrability of trigonometric series and relations among the best approximation and the coefficients of trigonometric series. Theorem 3 and Theorem 4 are the first resul... We generalize several classical results on the integrability of trigonometric series and relations among the best approximation and the coefficients of trigonometric series. Theorem 3 and Theorem 4 are the first results on the relations among the weighted best approximation and the coefficients of trigonometric series. 展开更多
关键词 weighted Lp integrability best approximation modulus of continuity
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APPROXIMATION BY GENERALIZED MKZ-OPERATORS IN POLYNOMIAL WEIGHTED SPACES 被引量:1
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作者 Lucyna Rempulska Mariola Skorupka 《Analysis in Theory and Applications》 2007年第1期64-75,共12页
We prove some approximation properties of generalized Meyer-Konig and Zeller operators for differentiable functions in polynomial weighted spaces. The results extend some results proved in [1-3,7-16].
关键词 Meyer-Konig and Zeller operator polynomial weighted space approximation theorem
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WEIGHTED L_p-APPROXIMATION OF DERIVATIVES BY THE METHOD OF BETA OPERATORS 被引量:1
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作者 宋儒瑛 《Acta Mathematica Scientia》 SCIE CSCD 1999年第S1期575-582,共8页
The author consides Beta operators βnf on suitable Sobolev type subspace of Lp[0, ∞) and characterizes the global rate of approximation of derivatives f(r) through corresponding derivatives (βnf)(r) in an appropria... The author consides Beta operators βnf on suitable Sobolev type subspace of Lp[0, ∞) and characterizes the global rate of approximation of derivatives f(r) through corresponding derivatives (βnf)(r) in an appropriate weighted Lp-metric by the rate of Ditzian and Totik's r-th order weighted modulus of Smoothness. 展开更多
关键词 Beta operators weighted modulus of smoothness weighted K-functional
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WEIGHTED BEST LOCAL APPROXIMATION IN ORLICZ SPACE 被引量:1
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作者 S. Favier C. Ridolfi 《Analysis in Theory and Applications》 2008年第3期225-236,共12页
We present a common fixed point theorem for generalized asymptotically non- expansive and noncommuting mappings in normed linear spaces.
关键词 best local approximation φ-approximations balanced integers
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Concise review of relaxations and approximation algorithms for nonidentical parallel-machine scheduling to minimize total weighted completion times 被引量:1
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作者 Li Kai Yang Shanlin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第4期827-834,共8页
A class of nonidentical parallel machine scheduling problems are considered in which the goal is to minimize the total weighted completion time. Models and relaxations are collected. Most of these problems are NP-hard... A class of nonidentical parallel machine scheduling problems are considered in which the goal is to minimize the total weighted completion time. Models and relaxations are collected. Most of these problems are NP-hard, in the strong sense, or open problems, therefore approximation algorithms are studied. The review reveals that there exist some potential areas worthy of further research. 展开更多
关键词 parallel machine SCHEDULING REVIEW total weighted completion time RELAXATION algorithm
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Weighted Approximation by Left Quasi-interpolants of Derivatives of Gamma Operators
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作者 JIANG HONG-BIAO 《Communications in Mathematical Research》 CSCD 2009年第4期289-298,共10页
In order to obtain much faster convergence, Miiller introduced the left Gamma quasi- interpolants and obtained an approximation equivalence theorem in terms of 2r wφ (f,t)p. Cuo extended the MiiUer's results to w... In order to obtain much faster convergence, Miiller introduced the left Gamma quasi- interpolants and obtained an approximation equivalence theorem in terms of 2r wφ (f,t)p. Cuo extended the MiiUer's results to wφ^24 (f, t)∞. In this paper we improve the previous results and give a weighted approximation equivalence theorem. 展开更多
关键词 Gamma operator quasi-interpolant weighted approximation modulus of smoothness derivative
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On Weighted Approximation by Modified Bernstein Operators for Functions with Singularities
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作者 Meiling Wang Dansheng Yu 《Analysis in Theory and Applications》 2014年第4期405-416,共12页
Della Vecchia et al. (see [2]) introduced a kind of modified Bernstein operators which can be used to approximate functions with singularities at endpoints on [0,1]. In the present paper, we obtain a kind of pointwi... Della Vecchia et al. (see [2]) introduced a kind of modified Bernstein operators which can be used to approximate functions with singularities at endpoints on [0,1]. In the present paper, we obtain a kind of pointwise Stechkin-type inequalities for weighted approximation by the modified Bemsetin operators. 展开更多
关键词 Modified Bernstein operators weighted approximation Stechkin inequality.
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WEIGHTED APPROXIMATION ON SZASZ-TYPE OPERATORS
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作者 Feng Guo (Taizhou University, China) 《Analysis in Theory and Applications》 2003年第1期47-54,共8页
In this paper, we use weighted modules ω(?)(f,t)w to study the pointwise approximation on Szasz-type operators, and obtain the direct and converse theorem, as well as characterizations of the pointwise approximation ... In this paper, we use weighted modules ω(?)(f,t)w to study the pointwise approximation on Szasz-type operators, and obtain the direct and converse theorem, as well as characterizations of the pointwise approximation of Jacobi-weighted Szasz-type operators. 展开更多
关键词 Szasz-type operator weighted modulus weighted approximation character itation
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Weighted Approximation of Kantorovich-Type Operator of Butzer-Hahn
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作者 田军 王绍钦 王玉 《Journal of Southwest Jiaotong University(English Edition)》 2005年第1期95-102,共8页
A kind of Kantorovich-type operator of Butzer-Hahn B*_n(f; x) on the bounded and integrable function space was introduced, and the properties of B*_n(f; x) were studied. Positive theorem, converse theorem, and the ord... A kind of Kantorovich-type operator of Butzer-Hahn B*_n(f; x) on the bounded and integrable function space was introduced, and the properties of B*_n(f; x) were studied. Positive theorem, converse theorem, and the order of weighted ~approximation of B*_n(f; x) were obtained. 展开更多
关键词 Kantorovich-type operator of Butzer-Hahn Properties of approximation weighted approximation
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A Study of Weighted Polynomial Approximations with Several Variables (II)
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作者 Ryozi Sakai 《Applied Mathematics》 2017年第9期1239-1256,共18页
In this paper we investigate weighted polynomial approximations with several variables. Our study relates to the approximation for by weighted polynomial. Then we will give some results relating to the Lagrange interp... In this paper we investigate weighted polynomial approximations with several variables. Our study relates to the approximation for by weighted polynomial. Then we will give some results relating to the Lagrange interpolation, the best approximation, the Markov-Bernstein inequality and the Nikolskii- type inequality. 展开更多
关键词 weighted POLYNOMIAL approximationS the LAGRANGE INTERPOLATION the Best of approximation INEQUALITIES
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Weighted Best Local Approximation
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作者 Segio Favier Claudia Ridolfi 《Analysis in Theory and Applications》 CSCD 2016年第4期355-372,共18页
In this survey the notion of a balanced best multipoint local approximation is fully exposed since they were treated in the LP spaces and recent results in Orlicz spaces. The notion of balanced point, introduced by Ch... In this survey the notion of a balanced best multipoint local approximation is fully exposed since they were treated in the LP spaces and recent results in Orlicz spaces. The notion of balanced point, introduced by Chui et al. in 1984 are extensively used. 展开更多
关键词 Best Local approximation multipoint approximation balanced neighborhood
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STRONG EQUIVALENCES OF APPROXIMATION NUMBERS AND TRACTABILITY OF WEIGHTED ANISOTROPIC SOBOLEV EMBEDDINGS
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作者 Jidong HAO Heping WANG 《Acta Mathematica Scientia》 SCIE CSCD 2020年第6期1765-1782,共18页
In this article,we study multivariate approximation defined over weighted anisotropic Sobolev spaces which depend on two sequences a={a j}j≥1 and b={b j}j≥1 of positive numbers.We obtain strong equivalences of the a... In this article,we study multivariate approximation defined over weighted anisotropic Sobolev spaces which depend on two sequences a={a j}j≥1 and b={b j}j≥1 of positive numbers.We obtain strong equivalences of the approximation numbers,and necessary and sufficient conditions on a,b to achieve various notions of tractability of the weighted anisotropic Sobolev embeddings. 展开更多
关键词 strong equivalences TRACTABILITY approximation numbers weighted anisotropic spaces analytic Korobov spaces
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Weighted Best Local Approximation
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作者 Segio Favier Claudia Ridolfi 《Analysis in Theory and Applications》 CSCD 2016年第1期1-19,共19页
In this survey, the notion of a balanced best multipoint local approximation is fully exposed since they were treated in the LP spaces and recent results in Orlicz spaces. The notion of balanced point, which was intro... In this survey, the notion of a balanced best multipoint local approximation is fully exposed since they were treated in the LP spaces and recent results in Orlicz spaces. The notion of balanced point, which was introduced by Chui et al. in 1984 are extensively used. 展开更多
关键词 Best local approximation multipoint approximation balanced neighborhood.
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A Note on Pad Approximants Pairs as Limits of Algebraic Polynomials Pairs of Weighted Best Approximation in Orlicz Spaces
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作者 F.E.Levis 《Analysis in Theory and Applications》 CSCD 2015年第3期253-259,共7页
In this short note, we show the behavior in Orlicz spaces of best approximations by algebraic polynomials pairs on union of neighborhoods, when the measure of them tends to zero.
关键词 Best approximation pair Pad′e approximant pair Orlicz spaces.
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WEIGHTED APPROXIMATION OF r-MONOTONE FUNCTIONS ON THE REAL LINE BY BERNSTEIN OPERATORS
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作者 Laiyi Zhu Xiaojie Zhu Xing Liu 《Analysis in Theory and Applications》 2011年第3期239-250,共12页
In this paper, we give error estimates for the weighted approximation of rmonotone functions on the real line with Freud weights by Bernstein-type operators.
关键词 Freud weight r-monotone function Bernstein-type operator
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The Approximation of Hermite Interpolation on the Weighted Mean Norm
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作者 Xin Wang Chong Hu Xiuxiu Ma 《American Journal of Computational Mathematics》 2015年第3期387-392,共6页
We research the simultaneous approximation problem of the higher-order Hermite interpolation based on the zeros of the second Chebyshev polynomials under weighted Lp-norm. The estimation is sharp.
关键词 HERMITE Interpolation operator CHEBYSHEV POLYNOMIAL DERIVATIVE approximation
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