IMPIEGO DELLA SEGMENTAZIONE MEDIANTECONTORNI ATTIVI NELL’IDENTIFICAZIONEDEGLI ELEMENTI METALLOGRAFICI E MORFOLOGICIDI INTERESSE NELLE GHISE SFEROIDALI Parole chiave: ghise sferoidali, analisi di immagine,segmentazione, contorni attivi Le ghise sferoidali costituiscono una famiglia di ghise piuttosto versatilecaratterizzata da un ampio intervallo di proprietà meccaniche che p...

The displacement of a calibrated camera between two images of a planar object can be estimated by decomposing a homography matrix. The aim of this document is to propose a new method for solving the homography decomposition problem. This new method provides analytical expressions for the solutions of the problem, instead of the traditional numerical procedures. As a result, expressions of the t...

The double porosity model allows to compute the pressure at a macroscopic scale in a fractured porous media, but requires the computation of some exchange coe cient characterizing the passage of the uid from and to the porous media (the matrix) and the fractures. This coe cient may be numerically computed by some Monte Carlo method, by evaluating the time a Brownian particle spend in the matrix...

we find an explicit expression of the tutte polynomial of an $n$-fan. we also find a formula of the tutte polynomial of an $n$-wheel in terms of the tutte polynomial of $n$-fans. finally, we give an alternative expression of the tutte polynomial of an $n$-wheel and then prove the explicit formula for the tutte polynomial of an $n$-wheel.

Yingying Wu, Matthew Williams, Sophie Bernard, Azeddine Driouich, Allan M. Showalter, and Ahmed Faik From the Department of Environmental and Plant Biology and the Molecular and Cellular Biology Program, Ohio University, Athens, Ohio 45701 and the Laboratoire “Glycobiologie et Matrice Extracellulaire Végétale,” Université de Rouen, UPRES-EA 4358, IFRMP 23, UFR des Sciences et Techniques, F-7682...

Ce travail considère, décrit et discute l’implémentation de l’AHP-Tutor, un Système Tutoriel Intelligent (STI) enseignant divers concepts et méthodes de dérivation des priorités d’une matrice des comparaisons de l’AHP. Le but de notre système est de proposer des exercices. La théorie correspondante doit être acquise de façon traditionnelle en classe, par des livres ou par un enseignement assist...

Consider a N × n random matrix Yn = (Y n ij ) where the entries are given by Y n ij = σ(i/N,j/n) √ n Xn ij , the X n ij being centered i.i.d. and σ : [0, 1] 2 → [0,∞) being a continuous function called a variance profile. Consider now a deterministic N ×n matrix Λn = ( Λij ) whose off-diagonal entries are zero. Denote by Σn the non-centered matrix Yn+Λn and by N ∧n = min(N,n). Then under the as...

We consider the solution of sparse linear systems using direct methods via LU factorization. Unless the matrix is positive definite, numerical pivoting is usually needed to ensure stability, which is costly to implement especially in the sparse case. The Random Butterfly Transformations (RBT) technique provides an alternative to pivoting and is easily parallelizable. The RBT transforms the orig...