Avant de devenir dessin à graver, la matrice du buriniste Albert Flocon est griffée lignes et figures mettant en tension l’espace plaque cuivre comme un champ forces devenir. L’étude graphie des propos d’Albert permet d’établir aujourd’hui liens entre les formes récurrentes relevées dans ses dessins préparatoires perceptions visuelles synesthètes étudiées par le neurologue américain Richard Cyt...

Graph/hypergraph partitioning models and methods have been successfully used to minimize the communication requirements among processors in several parallel computing applications. Parallel sparse matrix-vector multiplication (SpMxV) is one of the representative applications that renders these models and methods indispensable in many scientific computing contexts. We investigate the interplay o...

The Singular Value Decomposition (SVD) of a matrix is a linear algebra tool that has been successfully applied to a wide variety of domains. The present paper is concerned with the problem of estimating the Jacobian of the SVD components of a matrix with respect to the matrix itself. An exact analytic technique is developed that facilitates the estimation of the Jacobian using calculations base...

This work is devoted to the study of a family of almost periodic one-dimensional Schrr odinger equations. We deene a monodromy matrix for this family. We study the asymptotic behavior of this matrix in the adiabatic case. Therefore, we develop a complex WKB method for adiabatic perturbations of periodic Schrr odinger equations. At last, the study of the monodromy matrix enables us to get some s...

For every $1leq s< n$, the $s^{th}$ derivative of a polynomial $P(z)$ of degree $n$ is a polynomial $P^{(s)}(z)$ whose degree is $(n-s)$. This paper presents a result which gives generalizations of some inequalities regarding the $s^{th}$ derivative of a polynomial having zeros outside a circle. Besides, our result gives interesting refinements of some well-known results.

Let G be a simple graph and (G,) denotes the number of proper vertex colourings of G with at most  colours, which is for a fixed graph G , a polynomial in  , which is called the chromatic polynomial of G . Using the chromatic polynomial of some specific graphs, we obtain the chromatic polynomials of some nanostars.