Cage en liberté : réflexions libres

Notion de liberté en statistique mathématique

Réflexions sur la question fréquentielle en traitement du signal

New definitions are suggested for frequencies which may be instantaneous or not. The Heisenberg-Gabor inequality and the Shannon sampling theorem are briefly discussed.

Interactive specular and glossy reflections in dynamic scenes. (Réflexions spéculaires en temps interactif dans les scènes dynamiques)

Specular and glossy reflections are very important for our perception of 3D scenes, as they convey information on the shapes and the materials of the objects, as well as new view angles. They are commonly rendered using environment maps, with poor accuracy. We have designed more precise algorithms, under the constraints of interactive rendering and dynamic scenes, to allow applications such as ...

Quotients Homophones des Groupes Libres Homophonic Quotients of Free Groups

Ah, la recherche! Du temps perdu. Soit G le quotient du groupe libre a 26 g en era-teurs a; b; c; : : : ; z par les relations A = B, pour tout couple de mots (A; B) pouvant avoir la m^ eme prononciation en anglais. (Un groupe d eeni d'une mani ere analogue a et e consid er e dans Landsburg 1986].) Notre but est de d eterminer la structure du groupe G. Théorème. G est trivial. Démonstration. (No...

On zero free sets Sobre los conjuntos libres de ceros

Let G be a finite abelian group and let ZFSs(G) and μs(G) be respectively, the set of zero free sets and the set of minimal zero sets of G. The Olson constant, O(G), is 1 + max{|S| : S ∈ ZFSs(G)} and the strong Davenport constant, SD(G), is max{|S| : S ∈ μs(G)}. We show that there exists a very large class of groups G for which SD(G) = O(G). Then we give new values of SD(G).