Results 21 to 30 of about 372,791 (306)
On sign embeddings and narrow operators on $L_2$ [PDF]
, 2016 The goal of this note is two-fold. First we present a brief overview of "weak" embeddings, with a special emphasis on sign embeddings which were introduced by H. P. Rosenthal in the early 1980s. We also discuss the related notion of narrow operators, which was introduced by A. Plichko and M. Popov in 1990.
Beata Randrianantoanina
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On Enflo and narrow operators acting on $L_p$ [PDF]
, 2012 The first part of the paper is inspired by a theorem of H. Rosenthal, that if an operator on $L_1[0,1]$ satisfies the assumption that for each measurable set $A \subseteq [0,1]$ the restriction $T \bigl|_{L_1(A)}$ is not an isomorphic embedding, then the operator is narrow.
Volodymyr Mykhaylyuk +2 more
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Narrow operators and the Daugavet property for ultraproducts [PDF]
Positivity, 2005 We show that if $T$ is a narrow operator on $X=X_{1}\oplus_{1} X_{2}$ or $X=X_{1}\oplus_{\infty} X_{2}$, then the restrictions to $X_{1}$ and $X_{2}$ are narrow and conversely. We also characterise by a version of the Daugavet property for positive operators on Banach lattices which unconditional sums of Banach spaces inherit the Daugavet property, and
Dmitriy Bilik +3 more
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A note on narrow operators in $L_\infty$
Matematychni Studii, 2009 I. Krasikova
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On linear sections of orthogonally additive operators
Математичні Студії, 2022 Our first result asserts that, for linear regular operators acting from a Riesz space with the principal projection property to a Banach lattice with an order continuous norm, the $C$-compactness is equivalent to the $AM$-compactness. Next we prove that,
A. Gumenchuk, I. Krasikova, M. Popov
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Journal of Telecommunications and Information Technology, 2023 The paper presents an idea to use weak derivatives in interval global optimization. It allows using the Newton operator to narrow domains of non-differentiable functions. Preliminary computational experiments are also presented.
Bartłomiej Jacek Kubica
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Adaptive dating and fast proposals: Revisiting the phylogenetic relaxed clock model.
PLoS Computational Biology, 2021 Relaxed clock models enable estimation of molecular substitution rates across lineages and are widely used in phylogenetics for dating evolutionary divergence times.
Jordan Douglas +2 more
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Widening and narrowing operators for abstract interpretation [PDF]
Computer Languages, Systems & Structures, 2011 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
CORTESI, Agostino, ZANIOLI, Matteo
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Radial symmetry for a generalized nonlinear fractional p-Laplacian problem
Nonlinear Analysis, 2021 This paper first introduces a generalized fractional p-Laplacian operator (–Δ)sF;p. By using the direct method of moving planes, with the help of two lemmas, namely decay at infinity and narrow region principle involving the generalized fractional p ...
Wenwen Hou +3 more
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Narrow-linewidth fiber laser operating at 155 μm [PDF]
Optics Letters, 1987 We report the fabrication and operation of an Er(3+)-doped silica single-mode fiber laser operating at 1.55 microm and using a distributed fiber grating to provide feedback. The output bandwidth was measured as 0.04 nm, significantly narrower than the conventional cavity design. The laser had a threshold of 13 mW and a slope efficiency of 5%.
Jauncey, I.M. +3 more
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