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In this paper, we study the order of approximation for max-product Kantorovich sampling operators based upon generalized kernels in the setting of Orlicz spaces. We establish a quantitative estimate for the considered family of…

Functional Analysis · Mathematics 2025-02-25 Lorenzo Boccali , Danilo Costarelli , Gianluca Vinti

In this paper we obtained some direct and inverse theorems of approximation theory for $\psi$-differentiable functions in the metric weighted Orlicz spaces with weights, which belong to the class of Muckenhoupt.

Classical Analysis and ODEs · Mathematics 2015-01-13 Stanislav Chaichenko

In the present study, we establish both pointwise and uniform convergence in the space of logarithmically uniformly continuous and bounded functions for the max-product and max-min Durrmeyer-type exponential sampling operators. Furthermore,…

Functional Analysis · Mathematics 2025-12-09 Satyaranjan Pradhan , H. M. Srivastava , Madan Mohan Soren

The approximation of functions in Orlicz space by multivariate operators on simplex is considered. The convergence rate is given by using modulus of smoothness.

Functional Analysis · Mathematics 2021-01-25 Wan Ma , Lihong Chang , Yongxia Qiang

There are two notions of approximate Birkhoff-James orthogonality in a normed space. We characterize both the notions of approximate Birkhoff-James orthogonality in the space of bounded linear operators defined on a normed space. A complete…

Functional Analysis · Mathematics 2024-08-13 Kallol Paul , Debmalya Sain , Arpita Mal

In Musilak-Orlicz type spaces ${\mathcal S}_{\bf M}$, direct and inverse approximation theorems are obtained in terms of the best approximations of functions and generalized moduli of smoothness. The question of the exact constants in…

Classical Analysis and ODEs · Mathematics 2021-05-07 Fahreddin Abdullayev , Stanislav Chaichenko , Andrii Shidlich

If $L$ is a bounded linear operator mapping the Banach space $X$ into the Banach space $Y$ and $K$ is a compact set in $X$, then the Kolmogorov widths of the image $L(K)$ do not exceed those of $K$ multiplied by the norm of $L$. We extend…

Analysis of PDEs · Mathematics 2015-02-25 Albert Cohen , Ronald Devore

In this paper, we achieve new and improved numerical radius inequalities of operators defined on a Hilbert space by using Orlicz function and Hermite-Hadamard inequality. The upper bounds of various inequalities involving numerical radii…

Functional Analysis · Mathematics 2024-04-08 Amit Maji , Atanu Manna , Ram Mohapatra

This short note presents a linear algebraic approach to proving dimension lower bounds for linear methods that solve $L^2$ function approximation problems. The basic argument has appeared in the literature before (e.g., Barron, 1993) for…

Machine Learning · Computer Science 2025-08-20 Daniel Hsu

In this paper we provide explicit upper and lower bounds on certain $L^2$ $n$-widths, i.e., best constants in $L^2$ approximation. We further describe a numerical method to compute these $n$-widths approximately, and prove that this method…

Numerical Analysis · Mathematics 2020-09-28 Andrea Bressan , Michael S. Floater , Espen Sande

We establish very general criteria for the existence of multiplication operators between noncommutative Orlicz spaces $L^{\psi_0}(\tM)$ and $L^{\psi_1}(\tM)$. We then show that these criteria contain existing results, before going on to…

Operator Algebras · Mathematics 2025-03-19 Louis Labuschagne

In the Orlicz type spaces ${\mathcal S}_{M}$, we prove direct and inverse approximation theorems in terms of the best approximations of functions and moduli of smoothness of fractional order. We also show the equivalence between moduli of…

Classical Analysis and ODEs · Mathematics 2020-04-22 Stanislav Chaichenko , Andrii Shidlich , Fahreddin Abdullayev

Given an operator ideal I, a Banach space E has the I-approximation property if operators on E can be uniformly approximated on compact subsets of E by operators belonging to I. In this paper the I- approximation property is studied in…

Functional Analysis · Mathematics 2010-09-16 Sonia Berrios , Geraldo Botelho

In this bachelor's thesis we introduce three quantities for linear and bounded operators on quasi-Banach spaces which are entropy numbers, approximation numbers and Kolmogorov numbers. At first we establish the three quantities with some…

Functional Analysis · Mathematics 2025-08-12 Marcus Gerhold

We consider the family of integral operators $(K_{\alpha}f)(x)$ from $L^p[0,1]$ to $L^q[0,1]$ given by $$(K_{\alpha}f)(x)=\int_0^1(1-xy)^{\alpha -1}\,f(y)\,\operatorname{d}\!y, \qquad 0<\alpha<1.$$ The main objective is to find upper bounds…

Functional Analysis · Mathematics 2019-07-23 Duaine Lewis , Bernd Sing

Given an approximately continuous function $f$ in an Orlicz space $L^\Phi([a,b]),$ for a suitable class of convex functions $\Phi,$ we employ a characterization of the best monotone approximation set to establish its continuity, which in…

Functional Analysis · Mathematics 2026-04-29 Ana Benavente , Juan Costa Ponce , Sergio Favier

In this paper, we introduce Mellin-Steklov exponential samplingoperators of order $r,r\in\mathbb{N}$, by considering appropriate Mellin-Steklov integrals. We investigate the approximation properties of these operators in continuousbounded…

Functional Analysis · Mathematics 2024-10-15 D Ozer , S Kursun , T Acar

Inductive and projective type sequence spaces of sub- and super-exponential growth, and the corresponding inductive and projective limits of modulation spaces are considered as a framework for almost diagonalization of pseudo-differential…

Functional Analysis · Mathematics 2024-02-29 Stevan Pilipović , Nenad Teofanov , Filip Tomić

Orlicz spaces are generalizations of Lebesgue spaces. The sufficient and necessary conditions for generalized H\"{o}lder's inequality in Lebesgue spaces and in weak Lebesgue spaces are well known. The aim of this paper is to present…

Functional Analysis · Mathematics 2018-09-05 Ifronika , Al Azhary Masta , Muhammad Nur , Hendra Gunawan

We give sufficient conditions for the continuity in norm of the translation operator in the Musielak-Orlicz LM spaces. An application to the convergence in norm of approximate identities is given, whereby we prove density results of the…

Functional Analysis · Mathematics 2017-10-25 Ahmed Youssfi , Youssef Ahmida