Mardi 12 Mars
Heure: 
12:30  13:30 
Lieu: 
Salle B107, bâtiment B, Université de Villetaneuse 
Résumé: 
Reverse ChvatalGomory rank. 
Description: 
Roland Grappe We introduce the reverse ChvatalGomory rank r*(P) of an integral polyhedron P, defined as the supremum of the ChvatalGomory ranks of all rational polyhedra whose integer hull is P. A wellknown example in dimension two shows that there exist integral polytopes P with r*(P) infinite. We provide a geometric characterization of polyhedra with this property in general dimension, and investigate upper bounds on r*(P) when this value is finite. This is a joint work with Michele Conforti, Alberto Del Pia, Marco Di Summa and Yuri Faenza.&nbsp; 
Heure: 
14:00  17:00 
Lieu: 
Salle B107, bâtiment B, Université de Villetaneuse 
Résumé: 
Bipartite subfamilies of planar graphs 
Description: 
Juanjo Rué Perna I will survey the techniques used to get asymptotic results for subfamilies of planar graphs, as well as how to relate this methodology with the context of map enumeration. In the second part of the talk, I willexplain the ideas behind some ongoing projects related to the enumeration of bipartite subfamilies of graphs. 

