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Vanishing Theorems for p-Harmonic Forms on Submanifolds in Spheres
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作者 Nan Li 《Journal of Contemporary Educational Research》 2024年第4期48-53,共6页
In this paper,we present some vanishing theorems for p-harmonic forms on-super stable complete submanifold M immersed in sphere Sn+m.When 2≤1≤n-2,M has a flat normal bundle.Assuming that M is a minimal submanifold ... In this paper,we present some vanishing theorems for p-harmonic forms on-super stable complete submanifold M immersed in sphere Sn+m.When 2≤1≤n-2,M has a flat normal bundle.Assuming that M is a minimal submanifold andδ>1(n-1)p2/4n[p-1+(p-1)2kp],we prove a vanishing theorem for p-harmonicℓ-forms. 展开更多
关键词 p-harmonic forms Vanishing theorems SUBMANIFOLDS
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AN EXTENSION OF BROSOWSKI-MEINARDUS THEOREM ON INVARIANT APPROXIMATION 被引量:3
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作者 L.A.Khan A.R.Khan 《Analysis in Theory and Applications》 1995年第4期1-5,共5页
We obta(?) gener(?)ization of a fixed point th(?)of Dotson for nan-expansive mapptngs on star-sba p(?)sets and then(?)it to Prooe a unified Brosowski-M(?)us theorem on in(?)ariant approximatton in the setting,(?)fp-no... We obta(?) gener(?)ization of a fixed point th(?)of Dotson for nan-expansive mapptngs on star-sba p(?)sets and then(?)it to Prooe a unified Brosowski-M(?)us theorem on in(?)ariant approximatton in the setting,(?)fp-normed line(?)spaces. 展开更多
关键词 AN EXTENSION OF BROSOWSKI-MEINARDUS theorem ON INVARIANT approximation lim
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FIXED POINT THEOREMS AND BEST APPROXIMATION IN CONVEX METRIC SPACES 被引量:2
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作者 I.Beg N.Shahzad M.Iqbal 《Analysis in Theory and Applications》 1992年第4期97-105,共9页
Results regarding best approximation and best Simultaneous approximation on convex metric spaces are Obtained.Existence of fixed points for an ultimately nonexpansive semigroup of mappings is also shown.
关键词 CIG FIXED POINT theoremS AND BEST approximation IN CONVEX METRIC SPACES
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Approximation Theorem of K.Fan for Positive Mapping and Applications
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作者 朱江 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第1期55-59,共5页
In this paper, we investigate the validity of approximation theorm of K. Fan for a demicompact 1-set-contraction map defined on a closed ball,an annulus and a sphere in cones. From this, we improve all recent results ... In this paper, we investigate the validity of approximation theorm of K. Fan for a demicompact 1-set-contraction map defined on a closed ball,an annulus and a sphere in cones. From this, we improve all recent results of Lin [2]. As applications of our theorems, we discuss the existence of positive solutions to twopoint boundary value-problems of differential equations in Banach space. At the same time, the recent main results of (3) established by Guo Dajun are Generalized and supplemented. 展开更多
关键词 the approximation theorem of K. Fan demicompact 1-set-contraction maps twopoint boundary value-problems
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THE BEST APPROXIMATION AND COINCIDENCE THEOREMS FOR COMPOSITES OF ACYCLIC MAPPINGS
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作者 丁协平 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1999年第5期23-32,共10页
Some new coincidence theorem s involving a new class of set_valued mappings containing composites of acyclic mappings defined in a contractible space are proved. For applications, some best approximation theorems an... Some new coincidence theorem s involving a new class of set_valued mappings containing composites of acyclic mappings defined in a contractible space are proved. For applications, some best approximation theorems and coincidence theorems for set-valued mappings are als o given. A number of known results in recent literature are improved and general ized by the theorems in this paper. 展开更多
关键词 coincidence theorems the best approximation contractible space composites of acyclic mappings
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DIRECT LOCAL AND GLOBAL APPROXIMATION THEOREMS FOR SOME LINEAR POSITIVE OPERATORS
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作者 Zoltán Finta 《Analysis in Theory and Applications》 2004年第4期307-322,共16页
In this paper we establish direct local and global approximation theorems for Baskakov type operators and Szasz - Mirakjan type operators, respectively.
关键词 direct approximation theorem Baskakov type operator Szasz-Mirakjan type operator
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Pointwise Approximation Theorems for Combinations of Bernstein Polynomials with Inner Singularities
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作者 Wenming Lu Lin Zhang 《Applied Mathematics》 2011年第4期389-397,共9页
It is well-known that Bernstein polynomials are very important in studying the characters of smoothness in theory of approximation. A new type of combinations of Bernstein operators are given in [1]. In this paper, we... It is well-known that Bernstein polynomials are very important in studying the characters of smoothness in theory of approximation. A new type of combinations of Bernstein operators are given in [1]. In this paper, we give the Bernstein-Markov inequalities with step-weight functions for combinations of Bernstein polynomials with inner singularities as well as direct and inverse theorems. 展开更多
关键词 BERNSTEIN Polynomials INNER SINGULARITIES POINTWISE approximation Bernstein-Markov Inequalities Direct and Inverse theoremS
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SOME APPROXIMATION THEOREMS FOR MODIFIED BERNSTEIN-DURRMEYER OPERATORS
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作者 Li Song (Zhejiang University,China) 《Analysis in Theory and Applications》 1994年第4期1-12,共12页
The modified Bernstein-Durrmeyer operators discussed in this paper are given by M_nf≡M_n(f,x)=(n+2)P_(n,k)∫_0~1p_n+1.k(t)f(t)dt, where We will show,for 0<α<1 and 1≤p≤∞ M,f-f_p=O(n^-a)ω_Φ~2(f,t)_p=O(t^(2a... The modified Bernstein-Durrmeyer operators discussed in this paper are given by M_nf≡M_n(f,x)=(n+2)P_(n,k)∫_0~1p_n+1.k(t)f(t)dt, where We will show,for 0<α<1 and 1≤p≤∞ M,f-f_p=O(n^-a)ω_Φ~2(f,t)_p=O(t^(2a)), |M_n f-f(x)|≤M(x(1-x)/n+1/_n2)~a/2ω(f,t)=O(t^a), where otherwise. 展开更多
关键词 WILL SOME approximation theoremS FOR MODIFIED BERNSTEIN-DURRMEYER OPERATORS IIM 气刀 show
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Inverse Theorem of Approximation in L_p for the Stancu Integral-type Operators on a Simplex
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作者 ZHANG Chun-gou 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第1期4-9,共6页
In this paper, the integral-type Stancu operators on a simplex is considered and its inverse theorem of approximation in Lp(1≤ p 〈+∞)has been obtained.
关键词 SIMPLEX K-FUNCTIONAL the integral-type Stancu operators inverse theorem of approximation
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On Converse Theorem of Best Approximation by Polynomials in Bergman Spaces H_q^p(p>0,q>1)
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作者 邢富冲 《Chinese Quarterly Journal of Mathematics》 CSCD 1993年第4期89-98,共10页
A Bernstein type theorem and a converse theorem of best approximation by polynomials in Bergman spaces Hq^p(p>0,q>1) are proved.Some proofs and results in [1] are in proved.
关键词 Bergman spaces H_q^p(p>0 q>1) integral modulus of continuity Bernsterin type inequality best approximation by polynomial converse theorem
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AN APPLICATION OF A FIXED POINT THEOREM TO BEST SIMULTANEOUS APPROXIMATION
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作者 Isinat Beg Naseer Shahzad 《Analysis in Theory and Applications》 1994年第3期1-4,共4页
Using a recent result regarding the fixed points of multivalued mappings, the existence of invariant best simultaneous approximation in chainable metric space is proved.
关键词 AN APPLICATION OF A FIXED POINT theorem TO BEST SIMULTANEOUS approximation
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Approximation property of partition of unity and its applications 被引量:5
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作者 YinheWANG ZhiyuanLI SiyingZHANG 《控制理论与应用(英文版)》 EI 2004年第3期267-275,共9页
The linear combination of certain partition of unity, subordinate to certain open covering of a compact set, is proved to be capable of approximating to a continuous function at arbitrarily precision. By using proper ... The linear combination of certain partition of unity, subordinate to certain open covering of a compact set, is proved to be capable of approximating to a continuous function at arbitrarily precision. By using proper open covering and partition of unity, the robust nonlinear controllers and adaptive laws are designed for a class of nonlinear systems with uncertainties. The states and parameters of the closed-loop systems can be stabilized in the meaning of UUB ( uniformly ultimately bounded) via the robust nonlinear controllers and adaptive laws. Finally, an example shows the validity of method in this paper. 展开更多
关键词 Partition of unity approximating theorem Uncertain system UUB
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L^p APPROXIMATION BY GENERAL BERNSTEIN-DURRMEYER OPERATOR DEFINED ON SIMPLEX 被引量:1
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作者 CaoFeilong 《Analysis in Theory and Applications》 2004年第1期35-51,共17页
As a generalization of the Bernstein-Durrmeyer operatora defined on the simplex, a class of general Bernstein-Durrmeyer operators is introduced. With the weighted moduli of smoothness as a metric, we prove a strong di... As a generalization of the Bernstein-Durrmeyer operatora defined on the simplex, a class of general Bernstein-Durrmeyer operators is introduced. With the weighted moduli of smoothness as a metric, we prove a strong direct theorem and an inverse theorem of weak type for these operators by using a decom-position way. From the theorems the characterization of Lp approximation behavior is derived. 展开更多
关键词 general Bernstein-Durrmeyer operators direct theorem inverse theorem moduli of smoothness LP approximation
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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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Approximation properties for the genuine modi ed Bernstein-Durrmeyer-Stancu operators 被引量:1
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作者 CAI Qing-bo Ulku Dinlemez Kantar Bayram Cekim 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2020年第4期468-478,共11页
In this paper,we study on the genuine modified Bernstein-Durrmeyer-Stancu operators Gn(f,x)and investigate some approximation properties of them.Furthermore,we present a Voronovskaja type theorem for these operators.W... In this paper,we study on the genuine modified Bernstein-Durrmeyer-Stancu operators Gn(f,x)and investigate some approximation properties of them.Furthermore,we present a Voronovskaja type theorem for these operators.We also give some graphs and numerical examples to illustrate the convergence properties of these operators for certain functions. 展开更多
关键词 genuine modi ed Bernstein-Durrmeyer-Stancu operators Voronovskaja type approximation theorem rate of convergence modulus of continuity
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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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APPROXIMATE SAMPLING THEOREM FOR BIVARIATE CONTINUOUS FUNCTION
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作者 杨守志 程正兴 唐远炎 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第11期1355-1361,共7页
An approximate solution of the refinement equation was given by its mask, and the approximate sampling theorem for bivariate continuous function was proved by applying the approximate solution . The approximate sampli... An approximate solution of the refinement equation was given by its mask, and the approximate sampling theorem for bivariate continuous function was proved by applying the approximate solution . The approximate sampling function defined uniquely by the mask of the refinement equation is the approximate solution of the equation , a piece-wise linear function , and posseses an explicit computation formula . Therefore the mask of the refinement equation is selected according to one' s requirement, so that one may controll the decay speed of the approximate sampling function . 展开更多
关键词 approximate sampling theorem bivariate continuous signal refinement equation mask of refinement equation
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APPROXIMATION BY SOME OPERATORS OF SZASZ-MIRAKYAN TYPE
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作者 L.Rempulska Z.Walczak 《Analysis in Theory and Applications》 2004年第1期1-15,共15页
In this paper we give theorems on the degree of approximation of functions of one and two variables by certain operators of the Szasz-Mirakyan type.
关键词 Szasz-Mirakyan operator approximation theorem polynomial weighted space
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POINTWISE SIMULTANEOUS APPROXIMATION BY LEFT GAMMA QUASI-INTERPOLANTS
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作者 Hongbiao Jiang 《Analysis in Theory and Applications》 2008年第2期120-128,共9页
Recently some classical operator quasi-interpolants were introduced to obtain much faster convergence. We consider left Gamma quasi-interpolants and give a pointwise simultaneous approximation equivalence theorem with... Recently some classical operator quasi-interpolants were introduced to obtain much faster convergence. We consider left Gamma quasi-interpolants and give a pointwise simultaneous approximation equivalence theorem with ωφλ^2r(f,t)∞ by means of unified the classical modulus and Ditzian-Totick modulus. 展开更多
关键词 gamma operator quasi-interpolant pointwise simultaneous approximation equivalent theorem
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Approximation of Generalized Bernstein Operators
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作者 Xiru Yang Chungou Zhang Yingdian Ma 《Analysis in Theory and Applications》 2014年第2期205-213,共9页
This paper is devoted to study direct and converse approximation theorems of the generalized Bemstein operators Cn (f, sn,x) via so-called unified modulus ωφλ^2 (f,t), 0 ≤ λ ≤1. We obtain main results as fol... This paper is devoted to study direct and converse approximation theorems of the generalized Bemstein operators Cn (f, sn,x) via so-called unified modulus ωφλ^2 (f,t), 0 ≤ λ ≤1. We obtain main results as followsωφλ^2 (f,t)=O(t^α)←→|Cn(f,sn,x)-f(x)|=O((n^-1/2δn^1-λ(x))^α),where δn^2(x)=max{φ^2(x),1/n} and 0〈α〈2. 展开更多
关键词 Bernstein type operator Ditzian-Totik modulus direct and converse approximation theorem.
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