APPROXIMATION BY A CLASS OF MODIFIED SZASZ-DURRMEYER OPERATORS

ThisprojectissupportedbyZhejiangProvincialFoundationofChina.1.IntroductionForjEC[0,1]ther-thBernsteinpolynomialisdefinedbyItwasshownbyH.BerensandG.G.Lorentz([2]in1972)thatif0相似文献   

Approximation by complex szász-durrmeyer operators in compact disks

In the present paper, we deal with the complex Szász-Durrmeyer operators and study Voronovskaja type results with quantitative estimates for these operators attached to analytic functions of exponential growth on compact disks. Also, the exact order of approximation is found.     

Approximation by Complex Baskakov-Szsz-Durrmeyer Operators in Compact Disks

In this paper, we deal with the complex Baskakov-Szsz-Durrmeyer mixed operators and study Voronovskaja type results with quantitative estimates for these operators attached to analytic functions of exponential growth in DR= {z ∈ C;|z| R}.Also, the exact order of approximation is found. The method used allows to construct complex Szsz-type and Baskakov-type approximation operators without involving the values on [0, ∞).     

Approximation by Complex Baskakov-Sz ′asz-Durrmeyer Operators in Compact Disks

In this paper, we deal with the complex Baskakov-Sz ′asz-Durrmeyer mixed operators and study Voronovskaja type results with quantitative estimates for these operators attached to analytic functions of ...     

Baskakov型算子同时逼近的点态估计

In this paper, for Baskakov, Baskakov-Kantorovich and Baskakov-Durrmyer operators Ln(f,x),we give a simultaneous approximation of equivalent theorem with ω^2ψλ (f, t) The theorem unites the corrosponding results of classical and the Ditzian-Totik moduli of smoothness.     

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本文首先构造了单纯形上积分型Stancu算子,其讨论了它对连续函数的逼近,运用Mamedov-Shisha和Devore-Freud量化方法,得到了该算子对连续函数及连续可微函数的逼近度,并给出它的Vonorovskya型渐近公式。     

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EQUIVALENT THEOREMS ON SIMULTANEOUS APPROXIMATION BY COMBINATIONS OF GAMMA OPERATORS

In this paper, some equivalent theorems on simultaneous approximation for combinations of Gamma operators by weighted moduli of smoothness ωφλ^r（f,t）wφ^s（0≤λ≤1）are given. The relation between derivatives of combinations of Gamma operators and smoothness of derivatives of functions is also investigated.     

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CHARACTERIZATIONS OF COMPACT OPERATORS ON SOME EULER SPACES OF DIFFERENCE SEQUENCES OF ORDER m

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一类Post-Widder算子线性组合的加权Lp逼近

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Quantitative estimates for a new complex Durrmeyer operator in compact disks

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关于复平面有界闭集上的有理函数逼近

给出了复平面有界闭集的壳与有理函数的可逼近性之间的关系定理。     

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