共查询到20条相似文献,搜索用时 31 毫秒
1.
Xin Li 《Advances in Computational Mathematics》1994,2(3):343-355
The objective of this paper is to give an interrelation between Hankel oeprators on the unit disc and Hankel operators on
the half-plane. As an application, the AAK result on the half-plane is established and the rate of best Hankel approximation
on the halfplane is derived.
Research partially supported by the University Research Grants and Fellowship Committee at UNLV. 相似文献
2.
We prove that the weighted error of approximation by the Szász-Mirakyan-type operator introduced in [1] is equivalent to the
modulus of smoothness of the function. This result is analogous to previous results for Bernstein-type operators obtained
by Ditzian-Ivanov and Szabados.
Research supported by Hungarian Scientific Research Fund (OTKA), Grant No. T-049196. 相似文献
3.
S. D. Comer 《Algebra Universalis》1995,34(1):96-109
In 1951 Jónsson and Tarski showed that every Boolean algebra with operators could be embedded in a perfect (or canonical) extension. We obtain a similar result for regular double Stone algebras with operators. As a corollary we obtain another proof that every regular double Stone algebra can be represented as an algebra of rough subsets of an approximation space.Presented by J. Sichler.Research supported in part by The Citadel Development Foundation. 相似文献
4.
In the present article we find direct quantitative estimate for approximation of complex valued functions by linear combinations of the complex Phillips operators. Here we extend the recent results of Gal and Gupta (Mathematics without boundaries; Surveys in Interdisciplinary Research, 2014). We have been able to achieve the better approximation for the complex Phillips operators. 相似文献
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Dr. Friedmann W. Stallmann 《Numerische Mathematik》1970,15(4):297-305
Summary A new method for the solution of integral equations is presented. The method is based on direct approximation of Dirac's delta operator by linear combination of integral operators. This avoids some pitfalls which arise in more conventional numerical procedures for integral equations.Research sponsored by the U. S. Atomic Energy Commission under contract with the Union Carbide Corporation. the Union Carbide Corporation. 相似文献
7.
本文建立了Shepard-Lagrange算子逼近的正逆定理,证明了可以利用高阶光滑模来刻画Shepard-Lagrange算子的逼近性质.从而说明了Shepard-Lagrange算子比一般的Shepard算子具有更好的逼近性质.进一步,所用光滑模的阶梯函数非常广泛,这是多项式逼近所不具有的. 相似文献
8.
We present a few applications of the theory of Banach ideals of operators. In particular, we give operator characterizations
of the ℒ
p
spaces, compute the relative projection constant of isometric embeddings of Hilbert spaces inL
p
-spaces, and show that Π1 (E, F), the space of absolutely summing operators, is reflexive ifE andF are reflexive andE has the approximation property.
Research supported by NSF-GP-34193
Research supported by NSF-Science Development Grant 相似文献
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W_2~m空间中样条插值算子与最佳逼近算子的一致性 总被引:7,自引:0,他引:7
This paper discusses generalized interpolating splines which determined by n order linear differential operators, and the best operators of interpolating approximation in W_2~m spaces, The explicit constructive method for the reproducing kernel in W_2~m space is presented, and proves the uniformity of spline interpolating operators and the best operators of interpolating approximation W_2~m space by reproducing kernel. The explicit expression of approximation error on a bounded ball in W_2~m space, and error estimation of spline operator of approximation are obtained. 相似文献
12.
由线性微分算子确定的样条是连接多项式样条与希氏空间中抽象算子样条的重要环节,对微分算子样条的研究,既可从更高的观点揭示和概括多项式样条,又可启示我们去发现抽象算子样条的一些新的理论和应用. Green函数是研究微分算子样条的重要工具 [1],但在微分算子插值样条的计算及将样条用于数值分析中,再生核方法起着更重要的作用.文献[2][3]给出了与二阶线性微分算子插值样条有关的再生核解析表达式;由此得到了二阶微分算子插值样条与空间W_2~1[a,b]中最佳插值逼近算子的一致性;而且还利用再生核给出了Hi… 相似文献
13.
Barnabás Bede Emil Daniel Schwab Hajime Nobuhara Imre J. Rudas 《International Journal of Approximate Reasoning》2009,50(1):21-36
Recently, it has been shown that sum and product are not the only operations that can be used in order to define concrete approximation operators. Several other operations provided by fuzzy sets theory can be used. In the present paper, pseudo-linear approximation operators are investigated from the practical point of view in Image Processing. We study max–min, max–product Shepard type approximation operators together with Shepard operators based on pseudo-operations generated by an increasing continuous generator. It is shown that in several cases these outperform classical approximation operators based on sum and product operations. 相似文献
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首先,引入一种由斜坡函数激发的神经网络算子,建立了其对连续函数逼近的正、逆定理,给出了其本质逼近阶.其次,引入这种神经网络算子的线性组合以提高逼近阶,并且研究了这种组合的同时逼近问题.最后,利用Steklov函数构造了一种新的神经网络算子,建立了其在L~p[a,b]空间逼近的正、逆定理. 相似文献
16.
Ali Karaisa 《Mathematical Methods in the Applied Sciences》2016,39(9):2401-2410
In this study, we introduce the Durrmeyer type Jakimoski–Leviatan operators and examine their approximation properties. We study the local approximation properties of these operators. Further, we investigate the convergence of these operators in a weighted space of functions and obtain the approximation properties. Furthermore, we give a Voronovskaja type theorem for the our new operators. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
17.
We estimate pointwise convergence rates of approximation for functions with derivatives of bounded variation and for functions which are exponentially bounded and have derivatives locally of bounded variation. The approximation is made through the operation of a sequence of integral operators with not necessarily positive kernel functions. The general result is then applied to deduce estimates for Beta operators, Hermite-Fejér operators, Picard operators, Gauss-Weierstrass operators, Baskakov operators, Mirakjan-Szász operators, Bleimann-Butzer-Hahn operators, Phillips operators, and Post-Widder operators. 相似文献
18.
一类Bernstein型算子加权逼近 总被引:3,自引:1,他引:2
本文首先给出了一类用递归法定义的Bernsein型算子在一致逼近意义下的特征刻划,然后指出在通常的加权范数下,它虹无界的,通过引入的一种新范数,我们给出了该算子加Jacobi权逼近的特征刻划。 相似文献
19.
Mehmet Ali Özarslan 《Numerical Functional Analysis & Optimization》2016,37(1):92-105
In this article, we consider modified Bernstein-Kantorovich operators and investigate their approximation properties. We show that the order of approximation to a function by these operators is at least as good as that of ones classically used. We obtain a simultaneous approximation result for our operators. Also, we prove two direct approximation results via the usual second-order modulus of smoothness and the second-order Ditzian-Totik modulus of smoothness, respectively. Finally, some graphical illustrations are provided. 相似文献
20.
We estimate pointwise convergence rates of approximation for functions of bounded variation and for functions which are exponentially bounded and locally of bounded variation. The approximation is through the operation of a sequence of integral operators with not necessarily positive kernel functions. The general result is then applied to deduce estimates for particular operators, such as Beta operators, Fourier–Legendre operators, Picard operators, and Gauss–Weierstrass operators. 相似文献