Results 31 to 40 of about 282,700 (287)
Rational approximation on spheres [PDF]
Israel Journal of Mathematics, 2015 We quantify the density of rational points in the unit sphere $S^n$, proving analogues of the classical theorems on the embedding of $\q^n$ into $\r^n$. Specifically, we prove a Dirichlet theorem stating that every point $ \in S^n$ is sufficiently approximable, the optimality of this approximation via the existence of badly approximable points, and a ...
Kleinbock, Dmitry, Merrill, Keith
openaire +2 more sources
A method to obtain the best uniform polynomial approximation for the family of rational function [PDF]
Iranian Journal of Optimization, 2015 In this article, by using Chebyshev’s polynomials and Chebyshev’s expansion, we obtain the best uniform polynomial approximation out of P2n to a class of rational functions of the form (ax2+c)-1 on any non symmetric interval [d,e].
M. A. Fariborzi Araghi, F. Froozanfar
doaj
A piecewise homotopy Padé technique to approximate an arbitrary function
AIMS Mathematics, 2023 The Padé approximation and its enhancements provide a more accurate approximation of functions than the Taylor series truncation. A new technique for approximating functions into rational functions is proposed in this paper.
Mourad S. Semary +2 more
doaj +1 more source
New Lower Bound for the Generalized Elliptic Integral of the First Kind
Mathematics, 2022 In this paper, we obtain a new simple rational approximation for Ka(r): the inequality 2Ka(r)/π>g2r′/g1r′ holds for all r∈(0,1), where Ka(r) is the generalized elliptic integral of the first kind, r′=1−r2, g1r′ and g2r′ are specific primary and quadratic
Ling Zhu
doaj +1 more source
Rational approximation for solving an implicitly given Colebrook flow friction equation [PDF]
, 2019 The empirical logarithmic Colebrook equation for hydraulic resistance in pipes implicitly considers the unknown flow friction factor. Its explicit approximations, used to avoid iterative computations, should be accurate but also computationally efficient.
Brkić, Dejan, Praks, Pavel
core +5 more sources
Time after time – circadian clocks through the lens of oscillator theory
FEBS Letters, EarlyView.Oscillator theory bridges physics and circadian biology. Damped oscillators require external drivers, while limit cycles emerge from delayed feedback and nonlinearities. Coupling enables tissue‐level coherence, and entrainment aligns internal clocks with environmental cues.
Marta del Olmo +2 more
wiley +1 more source
IEEE Access, 2020 As the evolution of traditional electroencephalogram (EEG) monitoring unit for epilepsy diagnosis, wearable ambulatory EEG (WAEEG) system transmits EEG data wirelessly, and can be made miniaturized, discrete and social acceptable.
Wenshan Zhao +4 more
doaj +1 more source
Structural biology of ferritin nanocages
FEBS Letters, EarlyView.Ferritin is a conserved iron‐storage protein that sequesters iron as a ferric mineral core within a nanocage, protecting cells from oxidative damage and maintaining iron homeostasis. This review discusses ferritin biology, structure, and function, and highlights recent cryo‐EM studies revealing mechanisms of ferritinophagy, cellular iron uptake, and ...
Eloise Mastrangelo, Flavio Di Pisa
wiley +1 more source
Molecular Oncology, EarlyView.Following high dose rate brachytherapy (HDR‐BT) for hepatocellular carcinoma (HCC), patients were classified as responders and nonresponders. Post‐therapy serum induced increased BrdU incorporation and Cyclin E expression of Huh7 and HepG2 cells in nonresponders, but decreased levels in responders.
Lukas Salvermoser +14 more
wiley +1 more source
Parameter N Analysis on the Rational-Talbot Algorithm for Numerical Inversion of Laplace Transform
Vetor, 2021 This article investigates the numerical inversion of the Laplace Transform by the Rational-Talbot method and analyzes the influence on the variation of the free parameter N established by the technique when applied to certain functions.
Elisandra Freitas +4 more
doaj +3 more sources