Results 41 to 50 of about 25,259 (306)
Journal of Inequalities and Applications, 2020 In this paper, we introduce a modified Krasnoselski–Mann type iterative method for capturing a common solution of a split mixed equilibrium problem and a hierarchical fixed point problem of a finite collection of k-strictly pseudocontractive nonself ...
Jong Kyu Kim, Prashanta Majee
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Norm Attaining Operators and Pseudospectrum [PDF]
Integral Equations and Operator Theory, 2009 It is shown that if $11$, the operator $I+T$ attains its norm. A reflexive Banach space $X$ and a bounded rank one operator $T$ on $X$ are constructed such that $\|I+T\|>1$ and $I+T$ does not attain its norm.
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Some inequalities for the Euclidean operator radius of two operators in Hilbert spaces
, 2006 Some sharp bounds for the Euclidean operator radius of two bounded linear operators in Hilbert spaces are given. Their connection with Kittaneh’s recent results which provide sharp upper and lower bounds for the numerical radius of linear operators are ...
Dragomir, Sever S., Dragomir, Sever S
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On the compactness and the essential norm of operators defined by infinite tridiagonal matrices
Concrete Operators, 2023 In this article, all sequences u{\boldsymbol{u}}, v{\boldsymbol{v}}, and w{\boldsymbol{w}} that define continuous and compact tridiagonal operators Tu,v,w{T}_{u,v,w} acting on the weighted sequence space lβ2{l}_{\beta }^{2} were characterized ...
Caicedo Alexander +2 more
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Irish Mathematical Society Bulletin, 2001 Let \(E\) be a Banach space that contains an infinite dimensional complemented subspace with a Schauder basis, and \(A\) an algebra of bounded operators on \(E\) that contains the finite rank operators and endowed with the operator norm. For a given elementary operator \(Ta=\sum_{i=1}^\ell a_iab_i\in \mathcal{E}\ell\) on \(A\), a new one is defined by \
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Unitarily invariant norms on operators
Acta Scientiarum Mathematicarum, 2022 Let $f$ be a symmetric norm on ${\mathbb R}^n$ and let ${\mathcal B}({\mathcal H})$ be the set of all bounded linear operators on a Hilbert space ${\mathcal H}$ of dimension at least $n$. Define a norm on ${\mathcal B}({\mathcal H})$ by $\|A\|_f = f(s_1(A), \dots, s_n(A))$, where $s_k(A) = \inf\{\|A-X\|: X\in {\mathcal B}({\mathcal H}) \hbox{ has rank ...
Chan, Jor-Ting, Li, Chi-Kwong
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Pediatric Blood &Cancer, EarlyView.ABSTRACT Background Central nervous system (CNS) involvement in childhood acute lymphoblastic leukemia (ALL) is assessed by cell counting and cytomorphology from cerebrospinal fluid (CSF) and is used for treatment stratification worldwide. The ratio of “CNS2” patients in clinical trials ranges from 3% to 40%, with unclear prognostic significance ...
Laura Almási +14 more
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The L∞/L2 Hankel operator/norm of sampled-data systems [PDF]
, 2018 This paper is concerned with the Hankel operator and the Hankel norm of sampled-data systems. Even though these systems are intrinsically periodically time-varying, no studies have taken this important feature into account in the treatment of the Hankel ...
Kim, Hoon Jung +3 more
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Approximation numbers of an infinite matrix on HpB spaces [PDF]
Egyptian Journal of Pure and Applied ScienceIn this paper, we study conditions that an infinite matrix has to satisfy in order to define a linear bounded operator from any weighted HpB space[1] with a weighted sequence of positive numbers into itself, and give upper and lower estimations of the ...
Nashat Faried, Hany El Deeb
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A Bibliometric Analysis of Publications in Uremic Toxins From 1991 to 2024
Therapeutic Apheresis and Dialysis, EarlyView.ABSTRACT Background Uremic toxins are a growing area of research in nephrology, with significant implications in the progression and treatment of chronic kidney disease (CKD) and the management of end‐stage kidney disease (ESKD). This bibliometric analysis aims to evaluate the global research trends, key contributors, and the impact of publications in ...
Yuh‐Shan Ho +7 more
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