Results 81 to 90 of about 26,208 (246)
Magnetic Resonance in Medicine, Volume 94, Issue 6, Page 2578-2592, December 2025.Abstract Purpose The clinical utility of conventional DCE‐MRI methods is limited by the use of conventional qualitative dynamic T1‐weighted images, resulting in poor reproducibility. This study presents the initial implementation of a new DCE‐magnetic resonance fingerprinting (DCE‐MRF) methodology to provide reproducible, quantitative assessments of ...
Christina J. MacAskill +13 more
wiley +1 more source
On Toeplitz and Kronecker structured covariance matrix estimation
2010 IEEE Sensor Array and Multichannel Signal Processing Workshop, 2010 A number of signal processing applications require the estimation of covariance matrices. Sometimes, the particular scenario or system imparts a certain theoretical structure on the matrices that are to be estimated. Using this knowledge allows the design of algorithms exploiting such structure, resulting in more robust and accurate estimators ...
Wirfält, Petter, Jansson, Magnus
openaire +3 more sources
A fast elementary algorithm for computing the determinant of toeplitz matrices [PDF]
, 2012 In recent years, a number of fast algorithms for computing the determinant of a Toeplitz matrix were developed. The fastest algorithm we know so far is of order $k^2\log{n}+k^3$, where $n$ is the number of rows of the Toeplitz matrix and $k$ is the ...
Cinkir, Zubeyir
core
Around multivariate Schmidt-Spitzer theorem
, 2013 Given an arbitrary complex-valued infinite matrix A and a positive integer n we introduce a naturally associated polynomial basis B_A of C[x0...xn]. We discuss some properties of the locus of common zeros of all polynomials in B_A having a given degree m;
Alexandersson, Per, Shapiro, Boris
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Numerical Linear Algebra with Applications, Volume 32, Issue 6, December 2025.ABSTRACT In this work, we propose a novel preconditioned minimal residual method for a class of real, nonsymmetric multilevel block Toeplitz systems, which generalizes an ideal preconditioner established in [J. Pestana. Preconditioners for symmetrized Toeplitz and multilevel Toeplitz matrices. SIAM Journal on Matrix Analysis and Applications, 40(3):870–
Grigorios Tachyridis, Sean Y. Hon
wiley +1 more source
The Spectra of Large Toeplitz Band Matrices with a Randomly Perturbed Entry [PDF]
, 2001 This report is concerned with the union $sp_{\Omega}^{(j,k)}T_{n}(a)$ of all possible spectra that may emerge when perturbing a large $n \times n$ Toeplitz band matrix $T_{n}(a)$ in the $(j,k)$ site by a number randomly chosen from some set $\Omega$. The
Boettcher, A. +2 more
core
Low‐Rank Geostatistical Inversion for Spatiotemporal Heterogeneity of Aquitard Hydraulic Parameters
Water Resources Research, Volume 61, Issue 12, December 2025.Abstract Many hydrogeological processes are intricately linked to both the spatial heterogeneity and temporal dynamics of the involved parameters. The variability in hydrogeological parameters across both space and time domains is defined as the spatiotemporal heterogeneity.
Chao Zhuang +8 more
wiley +1 more source
Advanced Engineering Research, 2015 The simplest topological properties of the approximate spectrum, namely the connectivity of its complement in the complex plane, are studied. A numerical verification of the lower bounds for the maximum number of the connected components of the limitary ...
Svetlana A. Zolotykh
doaj +1 more source
Transactions of the London Mathematical Society, Volume 12, Issue 1, December 2025.Abstract In subwavelength physics, a challenging problem is to characterise the spectral properties of finite systems of subwavelength resonators. In particular, it is important to identify localised modes as well as bandgaps and associated mobility edges.
Habib Ammari +2 more
wiley +1 more source
The asymptotic spectra of banded Toeplitz and quasi-Toeplitz matrices [PDF]
Toeplitz matrices occur in many mathematical, as well as, scientific and engineering investigations. This paper considers the spectra of banded Toeplitz and quasi-Toeplitz matrices with emphasis on non-normal matrices of arbitrarily large order and ...
Beam, Richard M., Warming, Robert F.
core +1 more source