Results 1 to 10 of about 131 (27)
A general method to study the convergence of nonlinear operators in Orlicz spaces
Advanced Nonlinear Studies, 2022 We continue the work started in a previous article and introduce a general setting in which we define nets of nonlinear operators whose domains are some set of functions defined in a locally compact topological group. We analyze the behavior of such nets
Vinti Gianluca, Zampogni Luca
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On approximation properties of some non-positive Bernstein-Durrmeyer type operators
Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2023 In this paper we shall introduce a new type of Bernstein Durrmeyer operators which are not positive on the entire interval [0, 1]. For these operators we will study the uniform convergence on all continuous functions on [0, 1] as well as a result given ...
Vasian Bianca Ioana
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Skew-symmetric and essentially unitary operators via Berezin symbols
Open Mathematics, 2020 We characterize skew-symmetric operators on a reproducing kernel Hilbert space in terms of their Berezin symbols. The solution of some operator equations with skew-symmetric operators is studied in terms of Berezin symbols.
Altwaijry Najla +3 more
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Inequalities of Hardy-Littlewood-Polya type for functions of operators and their applications [PDF]
, 2015 In this paper, we derive a generalized multiplicative Hardy-Littlewood-Polya type inequality, as well as several related additive inequalities, for functions of operators in Hilbert spaces.
Babenko, Vladyslav +2 more
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Sard's approximation processes and oblique projections [PDF]
, 2009 Three problems arising in approximation theory are studied. These problems have already been studied by Arthur Sard. The main goal of this paper is to use geometrical compatibility theory to extend Sard's results and get characterizations of the sets of ...
Corach, Gustavo +2 more
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Best approximation by diagonal compact operators [PDF]
, 2013 We study the existence and characterization properties of compact Hermitian operators C on a separable Hilbert space H such that ||C|| is less or equal than || C + D ||, for all D in D(K(H)). This property is equivalent to || C || = min{||C+D||: D in D(K(
Bottazzi, Tamara, Varela, Alejandro
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A General Approximation Approach for the Simultaneous Treatment of Integral and Discrete Operators
Advanced Nonlinear Studies, 2018 In this paper, we give a unitary approach for the simultaneous study of the convergence of discrete and integral operators described by means of a family of linear continuous functionals acting on functions defined on locally compact Hausdorff ...
Vinti Gianluca, Zampogni Luca
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Weighted projections into closed subspaces [PDF]
, 2013 In this paper we study $A$-projections, i.e. operators of a Hilbert space $\HH$ which act as projections when a seminorm is considered in $\HH$. $A$-projections were introduced by Mitra and Rao \cite{[MitRao74]} for finite dimensional spaces.
Corach, Gustavo +2 more
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Approximation results for a general class of Kantorovich type operators [PDF]
, 2014 We introduce and study a family of integral operators in the Kantorovich sense for functions acting on locally compact topological groups. We obtain convergence results for the above operators with respect to the pointwise and uniform convergence and in ...
Vinti, Gianluca, Zampogni, Luca
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A philosophy for the modelling of realistic nonlinear systems [PDF]
, 2003 First published in Proceedings of the American Mathematical Society in volume 132, number 2, by the American Mathematical Society Copyright © 2003 American Mathematical SocietyA nonlinear dynamical system is modelled as a nonlinear mapping from a set of ...
Howlett, P., Pearce, C., Torokhti, A.
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