Results 61 to 70 of about 1,586 (179)
ON AN EXTREMAL PROBLEM FOR POLYNOMIALS WITH FIXED MEAN VALUE
Ural Mathematical Journal, 2016 Let \(T_n^+\) be the set of nonnegative trigonometric polynomials \(\tau_n\) of degree \(n\) that are strictly positive at zero. For \(0\le\alpha\le2\pi/(n+2),\) we find the minimum of the mean value of polynomial \((\cos\alpha-\cos{x})\tau_n(x)/\tau_n(0)
Alexander G. Babenko
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Bounding Multivariate Trigonometric Polynomials
IEEE Transactions on Signal Processing, 2019 The extremal values of multivariate trigonometric polynomials are of interest in fields ranging from control theory to filter design, but finding the extremal values of such a polynomial is generally NP-Hard. In this paper, we develop simple and efficiently computable estimates of the extremal values of a multivariate trigonometric polynomial directly ...
Luke Pfister, Yoram Bresler
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Breaking Barriers in High‐Order Spectral Methods: The Intrinsic Matrix Approach
International Journal for Numerical Methods in Engineering, Volume 127, Issue 5, 15 March 2026.ABSTRACT This paper introduces a unified framework in Hilbert spaces for applying high‐order differential operators in bounded domains using Chebyshev, Legendre, and Fourier spectral methods. By exploiting the banded structure of differentiation matrices and embedding boundary conditions directly into the operator through a scaling law relating ...
Osvaldo Guimarães, José R. C. Piqueira
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Inequalities for trigonometric polynomials
Journal of Approximation Theory, 1991 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Department of Mathematics, University of Florida, Gainesville, Florida 32611, U.S.A. ( host institution ) +1 more
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A New Padé Approach to Modeling Wormholes in Dekel‐Zhao Dark Matter Halos
Annalen der Physik, Volume 538, Issue 3, March 2026.A matter‐first Padé strategy is introduced to build traversable wormholes from prescribed dark‐matter halos. Rational Padé fits approximately the Dekel–Zhao density and are analytically integrated to obtain a shape function that exactly reproduces the intended matter content, avoiding spurious poles of geometry‐first schemes.
Jonathan Alves Rebouças +4 more
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Positive trigonometric polynomials
, 2003 We study the boundary of the nonnegative trigonometric polynomials from the algebraic point of view. In particularly, we show that it is a subset of an irreducible algebraic hypersurface and established its explicit form in terms of resultants.
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Health Science Reports, Volume 9, Issue 3, March 2026.ABSTRACT Background Tuberculosis (TB) remains a significant public health challenge, necessitating accurate forecasting methodologies to support effective control and prevention strategies. This paper explores the application and comparative performance of single and hybrid time‐series models for forecasting TB incidence trends specifically in Somalia.
Hana Mahdi Dahir +4 more
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Polynomial and trigonometric splines
, 2021 Classes of simple polynomial and simple trigonometric splines given by Fourier series are considered. It is shown that the class of simple trigonometric splines includes the class of simple polynomial splines. For some parameter values, the polynomial splines coincide with the trigonometric ones; this allows to transfer to such trigonometric splines ...
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MathematicsThis study presents a novel fifth-order unequal-sized trigonometric weighted essentially non-oscillatory (US-TWENO) scheme and a novel hybrid US-TWENO (HUS-TWENO) scheme with a novel troubled cell indicator in a finite difference framework to address ...
Yanmeng Wang, Liang Li, Jun Zhu
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Feedrate Scheduling of NURBS Interpolation Based on a Novel Jerk-Continuous ACC/DEC Algorithm
IEEE Access, 2018 In order to improve the motion smoothness while maintaining the machining efficiency of the non-uniform rational B-spline (NURBS) interpolation, a novel jerk-continuous acceleration/deceleration (ACC/DEC) algorithm and the corresponding feedrate ...
Hepeng Ni +4 more
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