Results 61 to 70 of about 26,208 (246)
Fine Spectra of Symmetric Toeplitz Operators
Abstract and Applied Analysis, 2012 The fine spectra of 2-banded and 3-banded infinite Toeplitz matrices were examined by several authors. The fine spectra of n-banded triangular Toeplitz matrices and tridiagonal symmetric matrices were computed in the following papers: Altun, “On the fine
Muhammed Altun
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AIMS Mathematics, 2023 We consider the preconditioned iterative methods for the linear systems arising from the finite volume discretization of spatial balanced fractional diffusion equations where the fractional differential operators are comprised of both Riemann-Liouville ...
Xiaofeng Guo, Jianyu Pan
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Not every matrix is similar to a Toeplitz matrix
Linear Algebra and its Applications, 2001 The inverse eigenvalue problem in matrix calculus is considered. It is known that such a problem is always solvable in a class of Toeplitz matrices and, in particular, of real symmetric Toeplitz matrices [cf. \textit{P. Delsarte} and \textit{Y. Genin}, Lect. Notes Control Inf. Sci. 58, 194-213 (1984; Zbl 0559.15017); \textit{H. J. Landau}, J. Am. Math.
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Journal of Sleep Research, EarlyView.ABSTRACT This study investigates the impact of extensive visual procedural training on the temporal organisation of sleep spindles in healthy young adults. We selected 39 participants aged 16–20 and employed high‐density electroencephalography to assess spindle characteristics during two full nights of sleep, with daytime practising in a contour ...
Patrícia Gerván +4 more
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IEEE Photonics Journal, 2018 Privacy amplification is an indispensable procedure to share secure secret key between legitimate parties in quantum key distribution (QKD) because a portion of bits are still leaked to eavesdropper Eve after the secret reconciliation. Here, we propose a
Dengwen Li +4 more
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Journal of Forecasting, Volume 45, Issue 1, Page 316-334, January 2026.ABSTRACT In this paper, we study models for stochastic seasonality and compare the well‐known SARIMA models to Seasonal Autoregressive Unit Root Moving Average (SARUMA) models. SARUMA models assume that the polynomial of the stationarizing differencing operator has roots on the unit circle at some seasonal frequencies, while SARIMA models impose roots ...
Evangelos E. Ioannidis +1 more
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Polynomial sequences generated by infinite Hessenberg matrices
Special Matrices, 2017 We show that an infinite lower Hessenberg matrix generates polynomial sequences that correspond to the rows of infinite lower triangular invertible matrices. Orthogonal polynomial sequences are obtained when the Hessenberg matrix is tridiagonal. We study
Verde-Star Luis
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Combinatorics on number walls and the P(t)$P(t)$‐adic Littlewood conjecture
Mathematika, Volume 72, Issue 1, January 2026.Abstract In 2004, de Mathan and Teulié stated the p$p$‐adic Littlewood conjecture (p$p$‐LC) in analogy with the classical Littlewood conjecture. Let Fq$\mathbb {F}_q$ be a finite field P(t)$P(t)$ be an irreducible polynomial with coefficients in Fq$\mathbb {F}_q$. This paper deals with the analogue of p$p$‐LC over the ring of formal Laurent series over
Steven Robertson
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Toeplitz versus Hankel: semibounded operators [PDF]
Opuscula Mathematica, 2018 Our goal is to compare various results for Toeplitz \(T\) and Hankel \(H\) operators. We consider semibounded operators and find necessary and sufficient conditions for their quadratic forms to be closable. This property allows one to define \(T\) and \(
Dmitri R. Yafaev
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Civil Engineering Design, Volume 7, Issue 4, Page 147-168, December 2025.Abstract The German Research Foundation has established the priority program SPP 100+. Its subject is monitoring bridge structures in civil engineering. The data‐driven methods cluster deals with the use of measurements and their special global and local analysis methods, which complement each other in an overall multi‐scale concept in order to realize
Maximilian Rohrer +13 more
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