The performance of available methods for computing the polynomial coefficients of the quadratic function approximation is evaluated. By comparing the numerical results to those obtained by symbolic methods, for a variety of functions, the direct solution of the matrix equation and a variety of recursive algorithms are all shown to be numerically unstable. AMS classification [PDF]
, 1991 The performance of available methods for computing the polynomial coefficients of the quadratic function approximation is evaluated. By comparing the numerical results to those obtained by symbolic methods, for a variety of functions, the direct solution
McInnes, A.W., Balakrishnan, Easwaran
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Flexible Dielectric Acoustic Resonator Patch for Tissue Regeneration
Advanced Materials, EarlyView.A flexible dielectric acoustic resonator patch enables MHz‐range ultrasound generation through resonance amplification without using piezoelectric materials. Conformal integration on a curved substrate allows efficient acoustic delivery to tissue‐mimicking environments.
Donyoung Kang +7 more
wiley +1 more source
Chebyshev Approximations by Least Squares Method
Известия Иркутского государственного университета: Серия "Математика", 2020 We consider the problem of linear approximation in the form of the minimization problem of the weighted Chebyshev norm, and that in the form of the minimization problem of the weighted Euclidean norm of the residual vector.
V.I. Zorkaltsev, E. V. Gubiy
doaj +1 more source
Rethinking Charge Transport and Recombination in Donor‐Diluted Organic Solar Cells
Advanced Materials, EarlyView.Organic solar cells with 1–45% PM6 content in Y12 were studied to link structure and charge dynamics to performance. The conductivity follows a 3D percolation model without a sharp threshold. Donor dilution preserves the photogeneration yield, but limits the fill factor due to transport resistance losses.
Chen Wang +14 more
wiley +1 more source
Approximations to the Distribution of Quadratic Forms
The Annals of Mathematical Statistics, 1965 Positive definite quadratic forms in normal variates, which do not necessarily reduce to a multiple of a $\chi^2$ variate, arise quite naturally in estimation and hypothesis testing problems related to normal distributions and processes. A classical example is the problem of testing the difference between two sample means, $\bar x - \bar y$, where the $
openaire +2 more sources
Linear-quadratic approximation, external habit and targeting rules [PDF]
We examine the linear-quadratic (LQ) approximation of non-linear stochastic dynamic optimization problems in macroeconomics, in particular for monetary policy.
Pearlman, Joseph G. +2 more
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Advanced Materials, EarlyView.ABSTRACT Accurately knowing the frontier orbital energies of the structurally disordered small‐molecule organic semiconductors that are used in optoelectronic devices such as organic light‐emitting diodes is required to rationally improve their performance. Here, we show that these energies can be deduced with a large accuracy from the peak energies of
Christian B. McDonald +7 more
wiley +1 more source
VAR FOR QUADRATIC PORTFOLIO'S WITH GENERALIZED LAPLACE DISTRIBUTED RETURNS [PDF]
This paper is concerned with the e±cient analytical computation of Value-at-Risk (VaR) for portfolios of assets depending quadratically on a large number of joint risk factors that follows a multivariate Generalized Laplace Distribution.
Jules Sadefo-Kamdem, Raymond BRUMMELHUIS
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Second‐Harmonic Hyper‐Mie Optical Activity Enables Closed‐Loop Chiral Photochemistry
Advanced Materials, EarlyView.Nonlinear chiral photochemistry is demonstrated in CdTe/CdO nanohelices, where circularly polarized infrared light both drives and tracks photo‐oxidation via second‐harmonic scattering. This closed‐loop process reveals real‐time structural evolution, including shell fracturing and core exposure, accompanied by a transition from hyper‐Mie to hyper ...
Hoyeon Choi +6 more
wiley +1 more source
Some new continued fraction sequence convergent to the Somos quadratic recurrence constant
Journal of Inequalities and Applications, 2016 In this paper, we provide some new continued fraction approximation and inequalities of the Somos quadratic recurrence constant, using its relation with the generalized Euler constant.
Xu You, Shouyou Huang, Di-Rong Chen
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