Using groupoid S-central extensions, we present, for a compact simple Lie group G, an infinite dimensional model of S-gerbe over the differential stack G/G whose Dixmier-Douady class corresponds to the canonical generator of the equivariant cohomology H G(G). c © 2001 Académie des sciences/Éditions scientifiques et médicales Elsevier SAS Gerbes Equivariantes sur les groupes de Lie simples compa...

Modern irrigation supply systems have diversified and yet methods of their classification have been overlooked. Thus, each system appears unique and this makes it difficult to integrate experience gained from their analysis. This paper postulates that ‘‘hydraulic command’’ is responsible for their diversification and creates ‘‘generic’’ variations among irrigation systems with each command meth...

We investigate the minimization of Newton’s functional for the problem of the body of minimal resistance with maximal height M > 0 [1] in the class of convex developable functions defined in a disc. This class is a natural candidate to find a (non-radial) minimizer in accordance with the results of [2]. We prove that the minimizer in this class has a minimal set in the form of a regular polygon...

RÉSUMÉ. L’analyse de terminaison des programmes logiques a été sujette à une recherche intensive durant les deux dernières décennies. La majorité des travaux s’est intéressée à la terminaison universelle gauche d’une classe donnée de requêtes, c’est-à-dire au fait que toutes les dérivations des requêtes de cette classe produites par un moteur Prolog sont finies. En revanche, l’étude du problème...

Based on the results of Blum, Shub and Smale 1], Meer 5], Cucker and Matamala 3] and Koiran 7], we develop the study of real computation models restricted to additive operations. More speciically we introduce some complexity classes deened by algebraic circuits and we study their relationships with the real computation model. We show that the languages accepted by nonuniform additive circuits o...

In his recent paper, “What a Real Argument is,” Ben Hamby attempts to provide an adequate theoretical account of “real” arguments. In this paper I present and evaluate both Hamby’s motivation for distinguishing “real” from non-“real” arguments and his articulation of the distinction. I argue that neither is adequate to ground a theoretically significant class of “real” arguments, for the articu...