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In the present note, we give the generalization of $\alpha-$Baskakov Durrmeyer operators depending on a real parameter $\rho$ > 0. We present the approximation results in Korovkin and weighted Korovkin spaces. We also prove the order of…

Classical Analysis and ODEs · Mathematics 2020-12-29 Jaspreet Kaur , Meenu Goyal

Among other things, we prove that, for a doubling weight $w$, $0< p\leq\infty$, $r\in{\mathbb N}_0$, and $0<\alpha <r+1 - 1/\lambda_p$, we have \[ E_n(f)_{p, w_n} = O(n^{-\alpha}) \iff \omega_\varphi^{r+1}(f, n^{-1})_{p, w_n} =…

Classical Analysis and ODEs · Mathematics 2015-07-20 Kirill A. Kopotun

We define a scale of weighted Morrey spaces which contains different weighted versions appearing in the literature. This allows us to obtain weighted estimates for operators in a unified way. In general, we obtain results for weights of the…

Functional Analysis · Mathematics 2019-10-31 Javier Duoandikoetxea , Marcel Rosenthal

Bernstein polynomials, long a staple of approximation theory and computational geometry, have also increasingly become of interest in finite element methods. Many fundamental problems in interpolation and approximation give rise to…

Numerical Analysis · Mathematics 2019-07-15 Larray Allen , Robert C. Kirby

The Bernstein polynomial basis sees significant use owing to its unique properties, particularly in the field of optimal control. However, the basis is known to have a slow rate of convergence to the function it approximates. With this in…

Optimization and Control · Mathematics 2025-09-15 Maxwell Hammond , Gage MacLin , Laurent Jay , Venanzio Cichella

In this article, we study the weighted composition operators preserving the class $\mathcal{P}_{\alpha}$ of analytic functions subordinate to $\frac{1+\alpha z}{1-z}$ for $|\alpha|\leq 1, \alpha \neq -1$. Some of its consequences and…

Functional Analysis · Mathematics 2018-02-07 Perumal Muthukumar , Saminathan Ponnusamy

In this note we study a quantitative version of Bernstein's approximation problem when the polynomials are dense in weighted spaces on the real line completing a result of S.~N.~Mergelyan (1960). We estimate in the logarithmic scale the…

Classical Analysis and ODEs · Mathematics 2022-11-28 Anna Kononova

We prove that several forms of the Bernstein polynomials with integer coefficients possess the property of simultaneous approximation, that is, they approximate not only the function but also its derivatives. We establish direct estimates…

Classical Analysis and ODEs · Mathematics 2019-04-23 Borislav R. Draganov

Let $L=-\Delta +V$ with non-negative potential $V$ satisfying some appropriate reverse H\"older inequality. In this paper, we study the boundedness of the commutators of some singular integrals associated to $L$ such as Riesz transforms and…

Classical Analysis and ODEs · Mathematics 2012-02-23 The Anh Bui

Extending an earlier estimate for the degree of approximation of overiterated univariate Bernstein operators towards the same operator of degree one, it is shown that an analogous result holds in the $d$-variate case. The method employed…

Classical Analysis and ODEs · Mathematics 2024-02-27 Ana-Maria Acu , Heiner Gonska

In this paper we establish sharp weighted bounds (Buckley type theorems) for one{sided maximal and fractional integral operators in terms of one{sided $A_p$ characteristics. Appropriate sharp bounds for strong maximal functions, multiple…

Functional Analysis · Mathematics 2014-03-04 Vakhtang Kokilashvili , Alexander Meskhi , Muhammad Asad Zaighum

We study the q-analogue of Euler-Maclaurin formula and by introducing a new q-operator we drive to this form. Moreover, approximation properties of q-Bernoulli polynomials is discussed. We estimate the suitable functions as a combination of…

Classical Analysis and ODEs · Mathematics 2017-11-06 Mohammad Momenzadeh , Ibrahim Yusuf Kakangi

In this paper we show that the weighted Bernstein-Walsh inequality in logarithmic potential theory is sharp up to some new universal constant, provided that the external field is given by a logarithmic potential. Our main tool for such…

Numerical Analysis · Mathematics 2017-07-26 Bernhard Beckermann , Thomas Helart

We characterize boundedness and compactness of pullback operators under holomorphic maps between Bargmann spaces of entire holomorphic functions with quadratic strictly plurisubharmonic exponential weights, extending a result of…

Complex Variables · Mathematics 2024-07-30 Reid Johnson

In this paper, we give direct theorems on point wise and global approximation by new variants of Bernstein-Durrmeyer operator, introduced by A.-M. et al.[1].

Classical Analysis and ODEs · Mathematics 2020-05-11 Asha Ram Gairola , Karunesh Kumar Singh

In this paper, we consider weighted Bergman spaces $\mathcal{B}_{\alpha,p}$ of log-subharmonic functions on the unit sphere. Using the isoperimetric inequality for the spherical metric we prove certain monotonicity property for super-level…

Complex Variables · Mathematics 2025-12-18 Vladan Jaguzović , Petar Melentijević

We extend two theorems of Krein concerning entire functions of Cartwright class, and give applications for the Bernstein weighted approximation problem.

Complex Variables · Mathematics 2007-05-23 Alexander Borichev , Mikhail Sodin

The aim of this paper is to study two-weight norm inequalities for fractional maximal functions and fractional Bergman operator defined on the upper-half space. Namely, we characterize those pairs of weights for which these maximal…

Classical Analysis and ODEs · Mathematics 2017-03-02 Benoît F. Sehba

We prove a version of the Bernstein-Walsh theorem on uniform polynomial approximation of holomorphic functions on compact sets in several complex variables. Here we consider subclasses of the full polynomial space associated to a convex…

Complex Variables · Mathematics 2017-01-23 Len Bos , Norm Levenberg

In weighted Orlicz type spaces ${\mathcal S}_{_{\scriptstyle \mathbf p,\,\mu}}$ with a variable summation exponent, the direct and inverse approximation theorems are proved in terms of best approximations of functions and moduli of…

Classical Analysis and ODEs · Mathematics 2020-04-22 Fahreddin G. Abdullayev , Stanislav O. Chaichenko , Meerim Imash kyzy , Andrii L. Shidlich