Search results for "Bernstein"

Approximation properties of λ-Kantorovich operators

2018

In the present paper, we study a new type of Bernstein operators depending on the parameter \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$\lambda\in[-1,1]$\end{document}λ∈[−1,1]. The Kantorovich modification of these sequences of linear positive operators will be considered. A quantitative Voronovskaja type theorem by means of Ditzian–Totik modulus of smoothness is proved. Also, a Grüss–Voronovskaja type theorem for λ-Kantorovich operators is provided. Some numerical examples which show the relevance of the res…

Conversion of Dupin Cyclide Patches into Rational Biquadratic Bézier Form

2005

This paper uses the symmetry properties of circles and Bernstein polynomials to establish a series of interesting barycentric properties of rational biquadratic Bezier patches. A robust algorithm is presented, based on these properties, for the conversion of Dupin cyclide patches into Bezier form. A set of conversion examples illustrates the use of this algorithm.

I volti del “Candide”: il romanzo di Voltaire, il musical di Bernstein e le sue varianti

2007

Il saggio ripercorre la genesi del "Candide" di Leonard Bernstein, dalla prima stesura del 1956 sino alla cosiddetta "final revised version" del 1989. Inoltre vengono analizzati e descritti gli sviluppi drammaturgici e i vari episodi musicali dell'opera.

Multivariate nonparametric estimation of the Pickands dependence function using Bernstein polynomials

2017

Abstract Many applications in risk analysis require the estimation of the dependence among multivariate maxima, especially in environmental sciences. Such dependence can be described by the Pickands dependence function of the underlying extreme-value copula. Here, a nonparametric estimator is constructed as the sample equivalent of a multivariate extension of the madogram. Shape constraints on the family of Pickands dependence functions are taken into account by means of a representation in terms of Bernstein polynomials. The large-sample theory of the estimator is developed and its finite-sample performance is evaluated with a simulation study. The approach is illustrated with a dataset of…

Experimental and Numerical Simulations of Flow and Heat Transfer in Heat Exchanger Elements Using Liquid Crystal Thermography

2004

Experimental and numerical investigation of heat transfer and fluid flow were conducted for classic heat exchanger elements (flat plate with fin-tubes in-line, staggered and with vortex generators) and corrugated-undulated ducts under transitional and weakly turbulent conditions. The dependence of average heat transfer and pressure drop on Reynolds number and geometrical parameters was investigated. Distributions of local heat transfer coefficient were obtained by using liquid crystal thermography and surface-averaged values were computed. Three-dimensional numerical simulations were conducted by a finite-volume method using a low-Reynolds number k-e model under the assumption of fully deve…

Il "Candide" da Voltaire e Bernstein

2015

Il saggio ricostruisce la genesi del "Candide" di Leonard Bernstein, e la storia delle sue tante stesure e riprese: dal primo progetto teatrale del 1953-54 sino cosiddetta "Scottish Opera Version, curata da John Mauceri, del 1988. Il percorso drammaturgico dello spettacolo viene messo a confronto con le narrazioni del romanzo di Voltaire e nella seconda parte del saggio vengono affrontati anche gli aspetti musicali e compositivi dell'opera.

OPTIMIZATIONS FOR TENSORIAL BERNSTEIN–BASED SOLVERS BY USING POLYHEDRAL BOUNDS

2010

The tensorial Bernstein basis for multivariate polynomials in n variables has a number 3n of functions for degree 2. Consequently, computing the representation of a multivariate polynomial in the tensorial Bernstein basis is an exponential time algorithm, which makes tensorial Bernstein-based solvers impractical for systems with more than n = 6 or 7 variables. This article describes a polytope (Bernstein polytope) with a number of faces, which allows to bound a sparse, multivariate polynomial expressed in the canonical basis by solving several linear programming problems. We compare the performance of a subdivision solver using domain reductions by linear programming with a solver using a c…

On the Complexity of the Bernstein Combinatorial Problem

2012

International audience

Práctica pedagógica en un centro de atención educativa singular de un barrio de acción preferente. Aproximación desde la teoría de Basil Bernst…

2014

Este trabajo pretende describir la modalidad pedagógica de docentes comprometidas políticamente con la educación en una sociedad democrática, para lo cual usamos la aproximación conceptual y metodológica de Basil Bernstein construida en una serie de investigaciones llevadas a cabo por Ana María Morais e Isabel Neves y su equipo de investigadoras, y Oscar Graizer y Almudena Navas, mis codirectoras. El campo de la educación de jóvenes en contextos de exclusión social convive con políticas educativas neoliberales, que son llevadas a la práctica por las mismas administraciones. Este campo se revela como un campo de conocimiento que cobra especial relevancia en el marco de nuestra sociedad. El e…

American political poetry from Whitman to 9/11

2012