Results 11 to 20 of about 141 (138)
Spectra of Weighted Composition Operators with Quadratic Symbols
Concrete Operators, 2022 Previously, spectra of certain weighted composition operators W ѱ, φ on H2 were determined under one of two hypotheses: either φ converges under iteration to the Denjoy-Wolff point uniformly on all of 𝔻 rather than simply on compact subsets, or φ is ...
Doctor Jessica +4 more
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Simple study designs in ecology produce inaccurate estimates of biodiversity responses
Journal of Applied Ecology, Volume 56, Issue 12, Page 2742-2754, December 2019., 2019 We suggest that more investment in more robust designs is needed in ecology since inferences from simpler designs, even with large sample sizes may be misleading. Facilitating this requires longer‐term funding and stronger research–practice partnerships. We also propose ‘accuracy weights’ and demonstrate how they can weight studies in three recent meta‐
Alec P. Christie +6 more
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A self adjoint expansion of a symmetric differential operator with operator coefficient [PDF]
, 2007 In this work, we prove that the closure of a symmetric operator L0which is formed by differential expression(L0y)(x) = −(p(x)y(x)) − Q(x)y(x)and with the boundary conditioncos α.y(0) + sinα.y(0) = 0is self adjoint where α ∈ (−∞,∞) in the space L2(0,∞; H )
Adıgüzelov, Ehliman, Karayel, Serpil
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Study of the property (bz) using local spectral theory methods
Arab Journal of Basic and Applied Sciences, 2023 For a bounded linear operator, by local spectral theory methods, we study the property [Formula: see text] which means that the difference of the approximate point spectrum with the upper semi-Fredholm spectrum coincides with the set of all finite-range ...
Elvis Aponte, Jose Soto, Ennis Rosas
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Gap localization of TE‐modes by arbitrarily weak defects
Journal of the London Mathematical Society, Volume 95, Issue 3, Page 942-962, June 2017., 2017 Abstract This paper considers the propagation of TE‐modes in photonic crystal waveguides. The waveguide is created by introducing a linear defect into a periodic background medium. Both the periodic background problem and the perturbed problem are modelled by a divergence type equation.
B. M. Brown +4 more
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International Journal of Mathematics and Mathematical Sciences, Volume 2004, Issue 27, Page 1437-1445, 2004., 2004 We investigate the spectrum of the differential operator Lλ defined by the Klein‐Gordon s‐wave equation y″ + (λ − q(x)) 2y = 0, x ∈ ℝ+ = [0, ∞), subject to the spectral parameter‐dependent boundary condition y′(0) − (aλ + b)y(0) = 0 in the space L2(ℝ+), where a ≠ ±i, b are complex constants, q is a complex‐valued function.
Gülen Başcanbaz-Tunca
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On linear chaos in function spaces
Demonstratio Mathematica, 2022 We show that, in Lp(0,∞){L}_{p}\left(0,\infty ) (1 ...
Jimenez John M., Markin Marat V.
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On some properties of Banach operators. II
International Journal of Mathematics and Mathematical Sciences, Volume 2004, Issue 47, Page 2513-2515, 2004., 2004 Using the notion of a Banach operator, wehave obtained a decompositional property of aHilbert space, and the equality of two invertible boundedlinear multiplicative operators on a normed algebra with identity.
A. B. Thaheem, A. R. Khan
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On new strong versions of Browder type theorems
Open Mathematics, 2018 An operator T acting on a Banach space X satisfies the property (UWΠ) if σa(T)∖ σSF+−$\begin{array}{} \sigma_{SF_{+}^{-}} \end{array} $(T) = Π(T), where σa(T) is the approximate point spectrum of T, σSF+−$\begin{array}{} \sigma_{SF_{+}^{-}} \end{array} $
Sanabria José +4 more
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B-Fredholm elements in primitive C*-algebras
Open Mathematics, 2022 Let A{\mathcal{A}} be a unital primitive C∗\ast -algebra. This article studies the properties of the B-Fredholm elements, the B-Weyl elements and the B-Browder elements in A{\mathcal{A}}. Particularly, this article describes the B-Fredholm element as the
Kong Yingying, Jiang Lining
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