Results 61 to 70 of about 5,196 (246)
Spectrally compact operators [PDF]
Tbilisi Mathematical Journal, 2010 We define the concept of a spectrally compact operator, and study the basic properties of these operators. We show that the class of spectrally compact operators is strictly contained in the class of compact operators and in the class of spectrally bounded operators.
Hejazian, Shirin, Rostamani, Mohadeseh
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Compact Weighted Composition Operators and Multiplication Operators between Hardy Spaces
Abstract and Applied Analysis, 2008 We estimate the essential norm of a compact weighted composition operator 𝑢𝐶𝜑 acting between different Hardy spaces of the unit ball in ℂ𝑁. Also we will discuss a compact multiplication operator between Hardy spaces.
Sei-Ichiro Ueki, Luo Luo
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Advanced Engineering Materials, EarlyView.A simple, cleanroom‐free method produces flexible mini‐coils using automated blade cutting. The process is fast, low‐cost, and supports diverse materials. The coils show strong durability and performance under repeated bending. Demonstrated use in resistor‐inductor filters and magnetic nanoparticle control proves their adaptability.
Changhao Ge +5 more
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Manuscripta Mathematica, 1975 I give an example of a positive compact operator on L2[0,1] which is not representable by any Lebesgue measurable function on [0,1]2. This example can be adapted to answer a question of H.H.Schaefer (§4 below).
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Compactness properties of operator multipliers [PDF]
Journal of Functional Analysis, 2009 We continue the study of multidimensional operator multipliers initiated in [arXiv:math/0701645]. We introduce the notion of the symbol of an operator multiplier. We characterise completely compact operator multipliers in terms of their symbol as well as in terms of approximation by finite rank multipliers. We give sufficient conditions for the sets of
Juschenko, K. +3 more
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单位球上βP空间到Zα型空间的加权Cesàro算子(Extended Cesàro operators from βP spaces to Zα spaces on the unit ball)
Zhejiang Daxue xuebao. Lixue ban, 2013 Boundary and compact of extended Cesàro operators from βP spaces to Zygmund type space in the unit ball are studied. With the methods of functional analysis and several complex variables, the necessary and sufficient conditions are given for extended ...
ZHAOYan-hui(赵艳辉)
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Simple eigenvectors of unbounded operators of the type “normal plus compact” [PDF]
Opuscula Mathematica, 2015 The paper deals with operators of the form \(A=S+B\), where \(B\) is a compact operator in a Hilbert space \(H\) and \(S\) is an unbounded normal one in \(H\), having a compact resolvent.
Michael Gil'
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Bioinspired Materials, Designs, and Manufacturing Strategies for Advanced Impact‐Resistant Helmets
Advanced Engineering Materials, EarlyView.This review explores how bioinspired materials, structures, and manufacturing strategies transform helmet design to achieve enhanced impact resistance. Drawing inspiration from nacre, porcupine quills, beetle exoskeletons, and skull architectures, it highlights advances in auxetic lattices, nanocomposites, and functionally graded foams.
Joseph Schlager +4 more
wiley +1 more source
Obstructions for compactness of Hankel operators: Compactness multipliers [PDF]
Illinois Journal of Mathematics, 2016 We establish a connection between compactness of Hankel operators and geometry of the underlying domain through compactness multipliers for the $\overline{\partial}$-Neumann operator. In particular, we prove that any compactness multiplier induces a compact Hankel operator.
Çelik, Mehmet, Zeytuncu, Yunus E.
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Generalized Composition Operators Between Weighted Dirichlet Type Spaces and Bloch Type Spaces
Journal of Mathematical Extension, 2012 We characterize bounded and compact generalized composition operators between Bloch type spaces and weighted Dirichlet type spaces. Then, we show that these results can be employed to characterize bounded and compact Volterra type operators between ...
Sh. Rezaei∗, H. Mahyar
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