Results 81 to 90 of about 54,917 (203)
A Class of Weighted Low Rank Approximation of the Positive Semidefinite Hankel Matrix
Journal of Applied Mathematics, 2015 We consider the weighted low rank approximation of the positive semidefinite Hankel matrix problem arising in signal processing. By using the Vandermonde representation, we firstly transform the problem into an unconstrained optimization problem and then
Jianchao Bai +3 more
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Spatial Image Gradient Estimation From the Diffusion MRI Profile
Magnetic Resonance in Medicine, Volume 95, Issue 5, Page 2980-2991, May 2026.ABSTRACT Purpose In the course of diffusion, water molecules encounter varying values for the relaxation‐time properties of the underlying tissue. This factor, which has rarely been accounted for in diffusion MRI (dMRI), is modeled in this work, allowing for the estimation of the gradient of relaxation‐time properties from the dMRI signal. Methods With
Iman Aganj +4 more
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The Moment Problem for Continuous Positive Semidefinite Linear functionals
, 2012 Let $\tau$ be a locally convex topology on the countable dimensional polynomial $\reals$-algebra $\rx:=\reals[X_1,...,X_n]$. Let $K$ be a closed subset of $\reals^n$, and let $M:=M_{\{g_1, ... g_s\}}$ be a finitely generated quadratic module in $\rx$. We
C. Berg +12 more
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Positive semidefinite propagation time
Discrete Applied Mathematics, 2016 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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Inequalities for selected eigenvalues of the product of matrices
, 2019 The product of a Hermitian matrix and a positive semidefinite matrix has only real eigenvalues.
Xi, Bo-Yan, Zhang, Fuzhen
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The positive semidefiniteness of partitioned matrices
Linear Algebra and its Applications, 1988 The author gives the character of the Löwner order, i.e. for symmetric matrices A and C such that \(C\leq A\), a symmetric matrix B satisfies \(C\leq B\leq A\) if and only if \(tr(R'B)\leq 1/2tr\{R'(A+C)\}+1/4tr(Q_ R)\) for all possible R, where \(Q_ R=\{(A-C)^{1/2}(R+R')(A-C)(R+R')(A- C)^{1/2}\}^{1/2}.\) An application to varieties of problems ...
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A quantum-inspired algorithm for estimating the permanent of positive semidefinite matrices
, 2017 We construct a quantum-inspired classical algorithm for computing the permanent of Hermitian positive semidefinite matrices, by exploiting a connection between these mathematical structures and the boson sampling model.
Cerf, N. J. +2 more
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Exact Ground States for Quasi 1D Systems with Hubbard Interaction [PDF]
Журнал нано- та електронної фізики, 2012 Using a positive semidefinite operator technique we deduced exact ground states for a modified diamond chain described by a non-integrable Hubbard model with on-site repulsion.
Zs. Gulácsi, E. Kovács
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, 2012 We consider a short rate model, driven by a stochastic process on the cone of positive semidefinite matrices.
ALESSANDRO GNOATTO +4 more
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Tongxin xuebao, 2013 For the robust adaptive beamforming problem of the gen l signal models, a robust beamforming algorithm based on the worst-case performance optimization with positive semi-definite constraints was proposed.
Ding-jie XU, Rui HE, Feng SHEN
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