Results 61 to 70 of about 3,406 (215)

Schatten-class truncated Toeplitz operators [PDF]

Proceedings of the American Mathematical Society, 2015
We investigate truncated Toeplitz operators belonging to the Schatten ideals. We completely characterize such operators when they have an analytic symbol or belong to the ideal of Hilbert-Schmidt operators. We also study model spaces generated by Blaschke products associated with thin sequences, model spaces generated by certain types of singular inner
Lopatto, Patrick, Rochberg, Richard
openaire   +2 more sources

Image space formalism of convolutional neural networks for k‐space interpolation

Magnetic Resonance in Medicine, Volume 94, Issue 6, Page 2680-2701, December 2025.
Abstract Purpose Noise resilience in image reconstructions by scan‐specific robust artificial neural networks for k‐space interpolation (RAKI) is linked to nonlinear activations in k‐space. To gain a deeper understanding of this relationship, an image space formalism of RAKI is introduced for analyzing noise propagation analytically, identifying and ...
P. Dawood, F. Breuer, M. Gram, I. Homolya, P. M. Jakob, M. Zaiss, M. Blaimer   +6 more
wiley   +1 more source

Dynamic contrast enhanced‐magnetic resonance fingerprinting (DCE‐MRF): A new quantitative MRI method to reliably assess tumor vascular perfusion

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, Yuran Zhu, Guanhua Wang, Bernadette O. Erokwu, Chetan B. Dhakan, Andrew Dupuis, Barbara J. Schiemann, Michael Kavran, Chunying Wu, William P. Schiemann, Mark A. Griswold, Xin Yu, Mark D. Pagel, Chris A. Flask   +13 more
wiley   +1 more source

An Optimal Preconditioned MINRES Method for Symmetrized Multilevel Block Toeplitz Systems With Applications

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

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, Zhongxu Li, Ubaid Ullah, Long Yan, Rui Hu, Zhi Dou, Zhifang Zhou, Jinguo Wang, Walter A. Illman   +8 more
wiley   +1 more source

On Bergman–Toeplitz operators in periodic planar domains

Transactions of the London Mathematical Society, Volume 12, Issue 1, December 2025.
Abstract We study spectra of Toeplitz operators Ta$T_a$ with periodic symbols in Bergman spaces A2(Π)$A^2(\Pi)$ on unbounded singly periodic planar domains Π$\Pi$, which are defined as the union of infinitely many copies of the translated, bounded periodic cell ϖ$\varpi$.
Jari Taskinen
wiley   +1 more source

Compact Operators on the Bergman Spaces with Variable Exponents on the Unit Disc of C

International Journal of Mathematics and Mathematical Sciences, 2018
We study the compactness of some classes of bounded operators on the Bergman space with variable exponent. We show that via extrapolation, some results on boundedness of the Toeplitz operators with general L1 symbols and compactness of bounded operators ...
Dieudonne Agbor
doaj   +1 more source

More subnormal Toeplitz operators.

Journal für die reine und angewandte Mathematik (Crelles Journal), 1986
In an earlier paper, J. J. Long and the author presented a subnormal Toeplitz operator that is neither normal nor analytic. It was constructed using the conformal map \(\psi\) of the disk onto the interior of the ellipse with vertices \(\pm i(1+\alpha)\) passing through \(\pm (1-\alpha)\) where ...
openaire   +1 more source

Reducing Subspaces of the Dual Truncated Toeplitz Operator

Journal of Function Spaces, 2018
We define the dual truncated Toeplitz operators and give some basic properties of them. In particular, spectrum and reducing subspaces of some special dual truncated Toeplitz operator are characterized.
Yinyin Hu, Jia Deng, Tao Yu, Liu Liu, Yufeng Lu   +4 more
doaj   +1 more source

Quantum propagation for Berezin-Toeplitz operators [PDF]

, 2020
Laurent Charles, Yohann Le Floch
openalex   +1 more source