Results 1 to 10 of about 594,373 (180)
A characteristic operator function for the class of n-hypercontractions
Journal of Functional Analysis, 2006 Let \(H\) be a complex, not necessarily separable Hilbert space. An operator \(T \in \mathcal{L}(H)\) is called \(n\)-hypercontraction if \(\sum_{k=0}^m (-1)^k\binom{m}{k}T^{*k}T^k\geq 0\) for all \(1\leq m \leq n.\) In particular, \(T\) is a contraction.
Anders Olofsson
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Equivalence of boundary eigenvalue operator functions and their characteristic matrix functions
Mathematische Annalen, 1987 Let \(E,G,F_ 1,F_ 2\) be Banach spaces and \(T^ D\in L(E,F_ 1)\), \(T^ R\in L(E,F_ 2)\) and \(Z\in L(G,E)\). Set \(F:=F_ 1\times F_ 2\) and \(T:=(T^ D,T^ R)\). Assume that \(T^ D\) is right invertible, Z is injective and \(N(T^ D)=R(Z)\). Then T is equivalent to a simple extension of its ''characteristic'' matrix \(M:=T^ RZ\).
Reinhard Mennicken, Manfred Möller
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On zeros of an entire function coinciding with exponential typequasi-polynomials, associated with a regular third-order differential operator on an interval [PDF]
Қарағанды университетінің хабаршысы. Математика сериясы, 2021 In this paper, we consider the question on study of zeros of an entire function of one class, which coincides with quasi-polynomials of exponential type.
N.S. Imanbaev, Ye. Kurmysh
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Spectral representation of stochastic integration operators [PDF]
MATEC Web of Conferences, 2022 The spectral representation for stochastic integration operators with respect to the Wiener process is proposed in the form of a composition of spectral characteristics used in the spectral form of mathematical description for control systems.
Rybakov Konstantin
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Boundedness of composition operators on Morrey spaces and weak Morrey spaces
Journal of Inequalities and Applications, 2021 In this study, we investigate the boundedness of composition operators acting on Morrey spaces and weak Morrey spaces. The primary aim of this study is to investigate a necessary and sufficient condition on the boundedness of the composition operator ...
Naoya Hatano +3 more
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The mathematical characteristic of the fifth order Laplace contour filters used in digital image processing [PDF]
Advances in Geodesy and Geoinformation, 2022 The Laplace operator is a differential operator which is used to detect edges of objects in digital images. This paper presents the properties of the most commonly used fifth-order pixels Laplace filters including the difference schemes used to derive ...
Ireneusz Winnicki +3 more
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Solar wind collisional heating [PDF]
, 2017 To properly describe heating in weakly collisional turbulent plasmas such as the solar wind, inter-particle collisions should be taken into account. Collisions can convert ordered energy into heat by means of irreversible relaxation towards the thermal ...
Brown, André EX +11 more
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The multiple interpolation de la Vallée Poussin problem
Vestnik Samarskogo Gosudarstvennogo Tehničeskogo Universiteta. Seriâ: Fiziko-Matematičeskie Nauki, 2015 This article is concerned with the solving of multiple interpolation de La Vallée Poussin problem for generalized convolution operator. Particular ate tention is paid to the proving of the sequential sufficiency of the set of solutions of the generalized
Valentin V Napalkov, Aigul U Mullabaeva
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On the quadratic Fock functor [PDF]
, 2012 We prove that the quadratic second quantization of an operator p on $L^2(\mathbb{R}^d)\cap L^\infty (\mathbb{R}^d)$ is an orthogonal projection on the quadratic Fock space if and only if p =MI, where MI is a multiplication operator by a characteristic ...
Dhahri, Ameur
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Characteristic Functions of Operators Similar to Unitary Operators [PDF]
Proceedings of the American Mathematical Society, 1976 Suppose T T denotes an operator which is similar to a unitary operator and θ T {\theta _T} denotes its characteristic function—considered as an operator on H 2 ( D T
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