Results 61 to 70 of about 5,271,349 (211)
Singular Value and Matrix Norm Inequalities between Positive Semidefinite Matrices and Their Blocks
Journal of MathematicsIn this paper, we obtain some inequalities involving positive semidefinite 2×2 block matrices and their blocks.
Feng Zhang +3 more
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Heinz均值凸性的一个注记(A note on the convexity of the Heinz means)
Zhejiang Daxue xuebao. Lixue ban, 2013 Recently, KITTANEH obtained an improvement of the Heinz inequality for all unitarily invariant norms. In this note, we obtain a refinement of KITTANEH's result. We shall conclude this paper with some numerical examples.
ZOULi-min(邹黎敏)
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Positive semidefinite completions of partial Hermitian matrices [PDF]
, 1992 We classify the ranks of positive semidefinite completions of Hermitian band matrices and other partially specified Hermitian matrices with chordal graphs and specified main diagonals.
Dancis, Jerome
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Laser &Photonics Reviews, EarlyView.Coherence variation is ubiquitous in nature, yet determining how it constrains physical observables remains challenging for multimode waves. To address this challenge, this work establishes a majorization‐based theory that identifies the supremum and infimum in the set of input coherence spectra, which provide optimal universal bounds for any linear ...
Shiyu Li, Cheng Guo
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Generalized Randić Estrada Indices of Graphs
Mathematics, 2022 Let G be a simple undirected graph on n vertices. V. Nikiforov studied hybrids of AG and DG and defined the matrix AαG for every real α∈[0,1] as AαG=αDG+(1−α)AG.
Eber Lenes +3 more
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Optimal Experimental Design for Fast and Accurate Relaxation Time Measurements in Magnetic Resonance
Magnetic Resonance in Chemistry, EarlyView.We apply D‐optimal experimental design to relaxation constant estimation in NMR relaxometry. The resulting sampling schedules concentrate measurements where the signal is most sensitive to the relaxation constant. Compared with conventional linear or logarithmic spacing, D‐optimal designs achieve better estimation accuracy and precision with fewer ...
Natalie E. Klein +4 more
wiley +1 more source
Adaptation of Symmetric Positive Semi-Definite Matrices for the Analysis of Textured Images
Cybernetics and Information Technologies, 2018 This paper addresses the analysis of textured images using the symmetric positive semi-definite matrix. In particular, a field of symmetric positive semi-definite matrices is used to estimate the structural information represented by the local ...
Akl Adib
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Control Design Based on Generalized Lur'e Lyapunov Functions for Sampled‐Data Lur'e Systems
International Journal of Robust and Nonlinear Control, EarlyView.ABSTRACT This article addresses the synthesis of stabilizing control laws for aperiodic sampled‐data Lur'e systems. Based on a hybrid system representation of the closed‐loop system and a timer‐dependent generalized Lur'e–Postnikov type Lyapunov function, stabilization conditions are obtained by separating decision variables with the application of two
Arthur Scolari Fagundes +2 more
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The role of identification in data‐driven policy iteration: A system theoretic study
International Journal of Robust and Nonlinear Control, EarlyView.Abstract The goal of this article is to study fundamental mechanisms behind so‐called indirect and direct data‐driven control for unknown systems. Specifically, we consider policy iteration applied to the linear quadratic regulator problem. Two iterative procedures, where data collected from the system are repeatedly used to compute new estimates of ...
Bowen Song, Andrea Iannelli
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Restricted Riemannian geometry for positive semidefinite matrices [PDF]
, 2023 We introduce the manifold of {\it restricted} $n\times n$ positive semidefinite matrices of fixed rank $p$, denoted $S(n,p)^{*}$. The manifold itself is an open and dense submanifold of $S(n,p)$, the manifold of $n\times n$ positive semidefinite matrices
Sun, Qiang +2 more
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