Results 11 to 20 of about 2,160,130 (367)
An extension of compact operators by compact operators with no nontrivial multipliers [PDF]
Journal of Noncommutative Geometry, 2016 We construct an essential extension of $\mathcal K(\ell_2({\mathfrak{c}}))$ by $\mathcal K(\ell_2)$, where ${\mathfrak{c}}$ denotes the cardinality of continuum, i.e., a $C^*$-algebra $\mathcal A\subseteq \mathcal B(\ell_2)$ satisfying the short exact ...
S. Ghasemi, P. Koszmider
semanticscholar +6 more sources
Smooth, Compact Operators [PDF]
Proceedings of the American Mathematical Society, 1979 It is a result of Holub’s [Math. Ann. 201 (1973), 157-163], that for T a compact operator on a real Hilbert space, T is smooth ⇔ ‖ T x 1 ‖ = ‖ T
Julien Hennefeld
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Compact and limited operators [PDF]
Mathematische Nachrichten, 2021 AbstractLet be a bounded linear operator between two real normed spaces. We characterize compactness of T in terms of differentiability of the Lipschitz functions defined on X with values in another normed space Z. Furthermore, using a similar technique we can also characterize finite rank operators in terms of differentiability of a wider class of ...
Bachir, Mohammed +2 more
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International Journal of Adaptive Control and Signal Processing, EarlyView., 2023 Summary In this contribution, we propose a detailed study of interpolation‐based data‐driven methods that are of relevance in the model reduction and also in the systems and control communities. The data are given by samples of the transfer function of the underlying (unknown) model, that is, we analyze frequency‐response data.
Quirin Aumann, Ion Victor Gosea
wiley +1 more source
Data‐driven performance metrics for neural network learning
International Journal of Adaptive Control and Signal Processing, EarlyView., 2023 Summary Effectiveness of data‐driven neural learning in terms of both local mimima trapping and convergence rate is addressed. Such issues are investigated in a case study involving the training of one‐hidden‐layer feedforward neural networks with the extended Kalman filter, which reduces the search for the optimal network parameters to a state ...
Angelo Alessandri +2 more
wiley +1 more source
Lipschitz compact operators [PDF]
Journal of Mathematical Analysis and Applications, 2014 We introduce the notion of Lipschitz compact (weakly compact, finite-rank, approximable) operators from a pointed metric space X into a Banach space E. We prove that every strongly Lipschitz p-nuclear operator is Lipschitz compact and every strongly Lipschitz p-integral operator is Lipschitz weakly compact. A theory of Lipschitz compact (weakly compact,
A. Jiménez-Vargas +2 more
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Compact covariance operators [PDF]
Proceedings of the American Mathematical Society, 1981 Let B be a real separable Banach space and R: i'->ia covariance operator. All representations of R in the form 2en ® e", (e", n > 1} c fi, are characterized. Necessary and sufficient conditions for R to be compact are ob- tained, including a generalization of Mercer's theorem. An application to character- istic functions is given. 1. Introduction.
Charles R. Baker, Ian W. McKeague
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Some new Fibonacci difference spaces of non-absolute type and compact operators [PDF]
, 2016 In this paper, we introduce the spaces and which are the BK-spaces of non-absolute type and also derive some inclusion relations. Further, we determine the duals of those spaces and also construct their bases.
Anupam Das, B. Hazarika
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Reductive operators that commute with a compact operator. [PDF]
Michigan Mathematical Journal, 1976 Robert L. Moore
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Compact well-bounded operators [PDF]
, 2001 Every compact well-bounded operator has a representation as a linear combination of disjoint projections reminiscent of the representation of compact self-adjoint operators. In this note we show that the converse of this result holds, thus characterizing
Doust, I., Qingping, C.
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