5 papers · 1 filter
Weyl distributions, spectral properties, and circulant approximation results for quaternion block multilevel Toeplitz matrix sequences
Ayoub Lailoune, Valerio Loi, Stefano Serra-Capizzano
The present work contains a comprehensive treatment of Weyl eigenvalue and singular value distributions, \val{Schatten -norm estimates, spectral localization and positive-defini…
Symbol-based multilevel block preconditioners for multilevel block Toeplitz systems: GLT-based analysis and applications
Sean Y. Hon, Congcong Li, Rosita L. Sormani +2
In recent years, there has been a renewed interest in preconditioning for multilevel Toeplitz systems, a research field that has been extensively explored over the past several dec…
A note on eigenvalues and singular values of variable Toeplitz matrices and matrix-sequences, with application to variable two-step BDF approximations to parabolic equations
Nikos Barakitis, Valerio Loi, Stefano Serra-Capizzano
Here, we consider a more general class of matrix-sequences and we prove that they belong to the maximal -algebra of generalized locally Toeplitz (GLT) matrix-sequences. Then, we…
Flipped structured matrix-sequences in image deblurring with general boundary conditions
Paola Ferrari, Isabella Furci, Stefano Serra-Capizzano
Motivated by a recent work on a preconditioned MINRES for flipped linear systems in imaging, in this note we extend the scope of that research for including more precise boundary c…
A preconditioned MINRES method for optimal control of wave equations and its asymptotic spectral distribution theory
Sean Hon, Jiamei Dong, Stefano Serra-Capizzano
In this work, we propose a novel preconditioned Krylov subspace method for solving an optimal control problem of wave equations, after explicitly identifying the asymptotic spectra…