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Related papers: Korovkin-type Theorems and Approximation by Positi…

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In the current short review we present the latest developments on linear maps $T:\mathbb{R}[x_1,\dots,x_n]\to\mathbb{R}[x_1,\dots,x_n]$, especially of $K$-positivity preserver, i.e., $Tp\geq 0$ on $K\subseteq\mathbb{R}^n$ for all…

Functional Analysis · Mathematics 2026-02-03 Philipp J. di Dio

In the present article we define the Phillips type modification of the generalized Sz\'asz-Mirakjan operators. Moments, recurrence formulas, and other identities are established for these operators. Approximation properties are also…

Classical Analysis and ODEs · Mathematics 2017-09-05 Vijay Gupta , G. C. Greubel

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

We generalize the classical Bernstein theorem concerning the constructive description of classes of functions uniformly continuous on the real line. The approximation of continuous bounded functions by entire functions of exponential type…

Complex Variables · Mathematics 2008-03-11 Vladimir Andrievskii

In this paper, we considered the problem of the simultaneous approximation of a function and its derivatives by means of the well-known neural network (NN) operators activated by sigmoidal function. Other than a uniform convergence theorem…

Functional Analysis · Mathematics 2025-02-25 Marco Cantarini , Danilo Costarelli

We introduce an operational rewriting-based semantics for strictly positive nested higher-order (co)inductive types. The semantics takes into account the "limits" of infinite reduction sequences. This may be seen as a refinement and…

Logic in Computer Science · Computer Science 2023-06-22 Łukasz Czajka

We develop a general theory of extensions of flat functors along geometric morphisms of toposes, and apply it to the study of the class of theories whose classifying topos is equivalent to a presheaf topos. As a result, we obtain a…

Category Theory · Mathematics 2014-06-23 Olivia Caramello

In this paper, we introduce a modification of the Szasz-Mirakjan-Kantorovich operators as well as Stancu operators [9] (or a Dunkl generalization of modified Szasz-Mirakjan-Kantrovich operators [5]) which preserve the linear functions.…

Classical Analysis and ODEs · Mathematics 2016-04-06 M. Mursaleen , Md. Nasiruzzaman

In this paper, we investigate the approximation behavior of both one and multidimensional neural network type operators for functions in $L^p(I^d,\rho)$, where $1\leq p<\infty$, associated with a general measure $\rho$ defined over a…

Functional Analysis · Mathematics 2025-12-23 Nitin Bartwal , A. Sathish Kumar

A landmark result from rational approximation theory states that $x^{1/p}$ on $[0,1]$ can be approximated by a type-$(n,n)$ rational function with root-exponential accuracy. Motivated by the recursive optimality property of Zolotarev…

Numerical Analysis · Mathematics 2019-06-28 Evan S. Gawlik , Yuji Nakatsukasa

In this paper we construct Stancu type q-Kantrovich-Sz\'asz-Mirakjan operators generated by Dunkl generalization of the exponential function. We obtain some approximation results using the Korovkin approximation theorem and the weighted…

Classical Analysis and ODEs · Mathematics 2016-03-29 M. Mursaleen , Taqseer Khan , Nasiruzzaman

In this work, we study the Kantorovich variant of max-min neural network operators, in which the operator kernel is defined in terms of sigmoidal functions. Our main aim is to demonstrate the $L^{p}$-convergence of these nonlinear operators…

Numerical Analysis · Mathematics 2024-07-08 İsmail Aslan , Stefano De Marchi , Wolfgang Erb

The motivation of this paper is the development of an optimisation method for solving optimisation problems appearing in Chebyshev rational and generalised rational approximation problems, where the approximations are constructed as ratios…

Optimization and Control · Mathematics 2020-11-06 R. Díaz Millán , Nadezda Sukhorukova , Julien Ugon

In the present paper, an inverse result of approximation, i.e., a saturation theorem for the sampling Kantorovich operators is derived, in the case of uniform approximation for uniformly continuous and bounded functions on the whole real…

Functional Analysis · Mathematics 2018-01-29 D. Costarelli , G. Vinti

We construct a variety of mappings of the unit interval into $\mathcal{L}^p([0,1])$ to generalize classical examples of $\mathcal{L}^p$-convergence of sequences of functions with simultaneous pointwise divergence. By establishing relations…

Classical Analysis and ODEs · Mathematics 2012-07-17 Vaios Laschos , Christian Mönch

We initiate an investigation into how much the existing theory of (nonselfadjoint) operator algebras on a Hilbert space generalizes to algebras acting on L^p spaces. In particular we investigate the applicability of the theory of real…

Functional Analysis · Mathematics 2020-01-08 David P. Blecher , N. Christopher Phillips

In this paper, we investigate the approximation properties of the summation-integral type operators as defined by Mishra et al. (Boll. Unione Mat. Ital. (2016) 8:297-305) and determine the local results as well as prove the convergence…

Functional Analysis · Mathematics 2020-02-25 Rishikesh Yadav , Ramakanta Meher , Vishnu Narayan Mishra

Hyper-Positive real, matrix-valued, rational functions are associated with absolute stability (the Lurie problem). Here, quantitative subsets of Hyper-positive functions, related through nested inclusions, are introduced. Structurally, this…

Optimization and Control · Mathematics 2019-12-19 Daniel Alpay , Izchak Lewkowicz

We provide strong $L_p$-rates of approximation of nonsmooth integral-type functionals of Markov processes by integral sums. Our approach is, in a sense, process insensitive and is based on a modification of some well-developed estimates…

Probability · Mathematics 2015-03-19 Iu. Ganychenko , A. Kulik

The Koopman operator approach provides a powerful linear description of nonlinear dynamical systems in terms of the evolution of observables. While the operator is typically infinite-dimensional, it is crucial to develop finite-dimensional…

Dynamical Systems · Mathematics 2025-03-03 Rishikesh Yadav , Alexandre Mauroy
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