Results 11 to 20 of about 12,791 (237)
Composition and Decomposition of Positive Linear Operators (VIII)
Axioms, 2023 In a series of papers, most of them authored or co-authored by H. Gonska, several authors investigated problems concerning the composition and decomposition of positive linear operators defined on spaces of functions.
Ana Maria Acu +2 more
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Composition of some positive linear integral operators
Demonstratio MathematicaThis article is devoted to constructing sequences of integral operators with the same Voronovskaja formula as the generalized Baskakov operators, but having different behavior in other respects.
Acu Ana-Maria, Rasa Ioan, Sofonea Florin
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Adjoints of Generalized Composition Operators with Linear Fractional Symbol
Extracta Mathematicae, 2016 Given a positive integer n and φ : U → U, an analytic self-map of the open unit disc in the complex plane, the generalized composition operator Cφ(n) is defined by Cφ(n)f = f (n) ◦ φ for f belonging to some Hilbert space of analytic functions on U.
Aliakbar Salaryan, Hamid Vaezi
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Integro-differential equations with bounded operators in Banach spaces [PDF]
Қарағанды университетінің хабаршысы. Математика сериясы, 2022 The paper investigates integro-differential equations in Banach spaces with operators, which are a composition of convolution and differentiation operators.
V.E. Fedorov, A.D. Godova, B.T. Kien
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Composition Vector Spaces as a New Type of Tri-Operational Algebras
Mathematics, 2021 The aim of this paper is to define and study the composition vector spaces as a type of tri-operational algebras. In this regard, by presenting nontrivial examples, it is emphasized that they are a proper generalization of vector spaces and their ...
Omid Reza Dehghan +2 more
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Network centrality and portfolio optimization using the genetic algorithm [PDF]
Mathematics and Modeling in Finance, 2021 This study aims to optimize the portfolio using the genetic operator and network centralization. The statistical population of the study is the top 50 companies of Tehran Stock Exchange, in the first quarter of 2021, and to calculate the size of ...
Asghar Abolhasani Hastiany +1 more
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Closed-Form Solutions of Linear Ordinary Differential Equations with General Boundary Conditions
Axioms, 2021 This paper deals with the solution of boundary value problems for ordinary differential equations with general boundary conditions. We obtain closed-form solutions in a symbolic form of problems with the general n-th order differential operator, as well ...
Efthimios Providas +2 more
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Norms of linear-fractional composition operators [PDF]
Transactions of the American Mathematical Society, 2003 Summary: We obtain a representation for the norm of the composition operator \(C_\phi\) on the Hardy space \(H^2\) whenever \(\phi\) is a linear-fractional mapping of the form \(\phi(z) = b/(cz +d)\). The representation shows that, for such mappings \(\phi\), the norm of \(C_\phi\) always exceeds the essential norm of \(C_\phi\).
Bourdon, Paul S. +3 more
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Convergence of Special Sequences of Semi-Exponential Operators
Mathematics, 2022 Several papers, mainly written by J. de la Call and co-authors, contain modifications of classical sequences of positive linear operators to obtain new sequences converging to limits which are not necessarily the identity operator.
Ana Maria Acu +3 more
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Metatimes, random measures and cylindrical random variables
Modern Stochastics: Theory and Applications, 2021 Metatimes constitute an extension of time-change to general measurable spaces, defined as mappings between two σ-algebras. Equipping the image σ-algebra of a metatime with a measure and defining the composition measure given by the metatime on the domain
Fred Espen Benth, Iben Cathrine Simonsen
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