Results 121 to 130 of about 71,699 (272)
Observer‐Based Stabilization of Positive Linear System With Disturbances
International Journal of Robust and Nonlinear Control, Volume 36, Issue 2, Page 732-746, 25 January 2026.ABSTRACT This article addresses the disturbance rejection and output stabilization control of positive linear systems. First, two disturbance observers (DOs) are proposed to estimate actuator‐channel and sensor‐channel disturbances, while a positive state observer is designed for state estimation.
Changsheng Zhou +5 more
wiley +1 more source
Positive semidefiniteness of estimated covariance matrices in linear models for sample survey data
Special Matrices, 2016 Descriptive analysis of sample survey data estimates means, totals and their variances in a design framework. When analysis is extended to linear models, the standard design-based method for regression parameters includes inverse selection probabilities ...
Haslett Stephen
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Semidefinite geometry of the numerical range
, 2010 The numerical range of a matrix is studied geometrically via the cone of positive semidefinite matrices (or semidefinite cone for short). In particular it is shown that the feasible set of a two-dimensional linear matrix inequality (LMI), an affine ...
Henrion, Didier
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Journal of Geophysical Research: Atmospheres, Volume 131, Issue 1, 16 January 2026.Abstract Biomass burning aerosols influence atmospheric temperatures by absorbing solar radiation, thereby altering the contrast between day and night temperatures. This study investigates the correlation between these aerosols and day‐night (D‐N) temperature changes over India by applying principal component analysis (PCA) in long‐term (2003–2021 ...
Lakhima Chutia +5 more
wiley +1 more source
From ƒ-Divergence to Quantum Quasi-Entropies and Their Use
Entropy, 2010 Csiszár’s ƒ-divergence of two probability distributions was extended to the quantum case by the author in 1985. In the quantum setting, positive semidefinite matrices are in the place of probability distributions and the quantum generalization is called ...
Dénes Petz
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Singular Values of Differences of Positive Semidefinite Matrices [PDF]
SIAM Journal on Matrix Analysis and Applications, 2001 Based on known results, the author shows relations between the singular values of two positive semidefinite matrices. Let \(A\) and \(B\) be complex positive semidefinite matrices of order \(n\) and let us denote as \(A \oplus B\) the block diagonal matrix with \(A\) and \(B\) on the diagonal. Using the common notation for singular values \(s_1(.) \geq
openaire +3 more sources
Communications on Pure and Applied Mathematics, Volume 79, Issue 1, Page 3-88, January 2026.Abstract We address the problem of regularity of solutions ui(t,x1,…,xN)$u^i(t, x^1, \ldots, x^N)$ to a family of semilinear parabolic systems of N$N$ equations, which describe closed‐loop equilibria of some N$N$‐player differential games with Lagrangian having quadratic behaviour in the velocity variable, running costs fi(x)$f^i(x)$ and final costs gi(
Marco Cirant, Davide Francesco Redaelli
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Mixed discriminants of positive semidefinite matrices
Linear Algebra and its Applications, 1989 If \(A^ k=(a^ k_{ij})\) are \(n\times n\) complex matrices \(k=1,2,...,n\), then their mixed discriminant \(D(A^ 1,...,A^ n)\) is \(\frac{1}{n!}\sum_{\sigma \in S_ n}\det (a_{ij}^{\sigma (j)})\), where \(S_ n\) is the symmetric group of degree n. If all the \(A^ k\) are equal this turns out to be det A, whereas if each \(A^ k\) is a diagonal matrix the
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Robust constrained weighted least squares for in vivo human cardiac diffusion kurtosis imaging
Magnetic Resonance in Medicine, Volume 95, Issue 1, Page 220-233, January 2026.Abstract Purpose Cardiac diffusion tensor imaging (cDTI) can investigate the microstructure of heart tissue. At sufficiently high b‐values, additional information on microstructure can be observed, but the data require a representation such as diffusion kurtosis imaging (DKI).
Sam Coveney +6 more
wiley +1 more source
Journal of Numerical Analysis and Approximation Theory, 2010 In this paper, we obtain new results concerning the generalizations of additive and multiplicative majorizations by means of exponential convexity. We prove positive semi-definiteness of matrices generated by differences deduced from majorization type ...
Naveed Latif, Josip Pečarić
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