2013


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Mardi 4 Juin
Heure: 00:59 - 15:00
Lieu: Amphithéâtre Euler, Institut Galilée, Université de Villetaneuse
Résumé: Exploring Scholarly Data with Rexplore
Description: Enrico Motta
Heure: 14:00 - 17:00
Lieu: Salle B107, bâtiment B, Université de Villetaneuse
Résumé: Combinatorics of the hard-squares model
Description: Andrew Rechnitzer
Vendredi 7 Juin
Heure: 00:59 - 14:00
Lieu: Salle B107, bâtiment B, Université de Villetaneuse
Résumé: Graphical Foundations for Dialogue Games
Description: Cai Wingfield In 2007, Harmer, Hyland and Melliès gave a formal mathematical foundation for game semantics using a notion they called a schedule, a structure describing interleavings of plays in games. Their definition was combinatorial in nature, but researchers often draw pictures when describing schedules in practice. Moreover, several proofs of key properties, such as that the composition of schedules is associative, involve cumbersome combinatorial detail, whereas in terms of pictures the proofs are straightforward, reflecting the geometry of the plane. Here, we give a geometric formulation of schedules, prove that they are isomorphic to Harmer et al.'s definitions, and illustrate their value by giving such geometric proofs. Harmer et al.'s notions may be combined to describe plays in multi-component games, and researchers have similarly developed intuitive graphical representations of plays in these games. We give a characterisation of these diagrams and explicitly describe how they relate to the underlying schedules, finally using this relation to provide new, intuitive proofs of key categorical properties.
This is a joint work with Guy McCusker and John Power.
Mardi 11 Juin
Heure: 14:00 - 17:00
Lieu: Salle B107, bâtiment B, Université de Villetaneuse
Résumé: Extreme statistics of non-intersecting Brownian motions
Description: Grégory Schehr Non-intersecting Brownian motions (BMs) havebeen the subject of numerous studies both in mathematics and in physics. In addition to theirdeep connection with random matrix theory, It was shown that they are at the heart of manyfundamental models of statistical physics, like stochastic growth models or directed paths in random media. In this talk I will review some recent results which we have obtained for the extreme statistics,like the maximal height, of such non-intersecting BMs.    Les marcheurs Browniens conditionnés à ne pas se croiser ontsuscité beaucoup d'intérêt ces dernièresannées, tant en mathématique (pour leurs aspectsprobabilistes et combinatoires) qu'en physique (comme desmodèles de polymères ou de transition de mouillage ou defusion). Dans cet exposé je présenterai un calcul exact dela distribution de la hauteur maximale d'une collection de N pontsBrowniens (appelés 'watermelons without wall') et de Nexcursions Browniennes (appelées 'watermelons with awall') conditionnés à ne pas se croiser. Je montreraique dans la limite asymptotique où N tend vers l'infini cettedistribution converge vers la distribution de Tracy-Widom quidécrit les fluctuations de la plus grande valeur propre dematrices aléatoires de l'ensemble gaussien orthogonal (GOEpour 'Gaussian Orthogonal Ensemble'). Je discuterai enfin uneapplication de ces résultats asymptotiques à desmodèles de croissance stochastique.
Jeudi 13 Juin
Heure: 10:30 - 13:30
Lieu: Salle B107, bâtiment B, Université de Villetaneuse
Résumé: Journée ANR Magnum
Description: 10h30 Aline Parreau (LIFL) Une preuve combinatoire du lemme local de Lovasz11h45 Julien David (LIPN) & Yann Ponty (LIX) présentation de RDos (Random Discrete Objects Suite): un ensemble d'outils pour la génération aléatoire d'objets combinatoires 12h30 Buffet en salle A20114h Mathieu Raffinot (LIAFA) Nouvelles avancées dans la recherche de motifs uniques ou consécutifs dans des permutations travail en commun avec D.l Belazzougui (Univ. of Helsinki), A. Pierrot (LIAFA) et S. Vialette (LIGM) 15h15 Axel Bacher (LIPN) Génération aléatoire d'arbres en taille exacte et linéaire en temps et en espace 16h15 Discussion : bilan et perspectives après 30 mois
Vendredi 14 Juin
Heure: 00:59 - 14:00
Lieu: Salle B107, bâtiment B, Université de Villetaneuse
Résumé: Some Results for Linear Logic Full Completeness
Description: Hugh Steele Many full completeness theorems have been established for fragments of
linear logic since the notion was first defined by Samson Abramsky and
Radha Jagadeesan in their 1992 paper. For the most part, these results
are obtained on a case-by-case basis: the subject of each proof is
precisely one category.

In this talk it is shown that the Hyland-Tan double glueing
construction can transform all tensor-generated compact closed
categories with finite biproducts into fully complete models of
unit-free MLL. The arguments employed are based around considering the
combinatorics behind the construction using standard linear algebra.
It is also discussed how another double glueing construction may be
able to create similar categories satisfying unit-free MALL full
completeness.
Mardi 18 Juin
Heure: 14:00 - 17:00
Lieu: Salle B107, bâtiment B, Université de Villetaneuse
Résumé: Where the really hard problems really are?
Description: Lenka Zdeborova
Lundi 1 Juillet
Heure: 00:59 - 16:00
Lieu: Salle B107, bâtiment B, Université de Villetaneuse
Résumé: After the f-score: applying parser output in sentiment analysis, grammatical error detection and quality estimation for machine translation
Description: Jennifer Foster several natural language processing applications, either because the "sense-making" applications such as sentiment analysis or question in "language proofing" applications such as grammar checking or experiments carried out in the National Centre for Language Technology parser output in three downstream applications, namely, sentiment translation. In all these experiments some kind of phrase structure used to parse the input, and in some cases, the phrase structures were structure trees and dependency graphs was employed in the downstream clear from these experiments that syntactic parsing always provides some syntactic information or what the relationship between the accuracy of F1 or labelled attachment accuracy) and its usefulness in the downstream 
Vendredi 5 Juillet
Heure: 00:59 - 14:30
Lieu: Salle B107, bâtiment B, Université de Villetaneuse
Résumé: Forcing in classical realizability: the case study of Herbrand trees
Description: Lionel Rieg Krivine presented in 2010 a methodology to combine Cohen's forcing with
the theory of classical realizability and showed that the forcing
condition can be seen as a reference that is not subject to backtracks.
The underlying classical program transformation was then analyzed by
Miquel (2011) in a fully typed setting in classical higher-order
arithmetic (PAw+).As a case study of this methodology, I present a method to extract a
Herbrand tree from a classical realizer of an existential formula,
following the idea of the proof of Herbrand theorem.  Unlike the
traditional proof based on Konig's lemma (using a fixed enumeration of
atomic formulas), our method is based on the introduction of a
particular Cohen real.  It is formalized as a proof in PAw+, making
explicit the construction of generic sets in this framework in the
particular case where the set of forcing conditions is arithmetical.  We
then analyze the algorithmic content of this proof.
Mercredi 10 Juillet
Heure: 13:30 - 16:30
Lieu: Salle B107, bâtiment B, Université de Villetaneuse
Résumé: Soutenance à mi-parcours
Description: Nguyen Hoang-Nghia
Heure: 14:30 - 17:30
Lieu: Salle B107, bâtiment B, Université de Villetaneuse
Résumé: Soutenance à mi-parcours
Description: Ladji Kane
Heure: 15:30 - 18:30
Lieu: Salle B107, bâtiment B, Université de Villetaneuse
Résumé: Soutenance à mi-parcours
Description: Alice Jacquot
Heure: 16:30 - 19:30
Lieu: Salle B107, bâtiment B, Université de Villetaneuse
Résumé: Goûter de clôture
Vendredi 12 Juillet
Heure: 00:59 - 12:00
Lieu: Amphi Copernic, Institut Galilée, Université de Villetaneuse
Résumé: Bisimulations from graphical encodings (DPOs, RPOs, cospans, and all that)
Description: Fabio Gadducci The talk presents a personal recollection of recent results on the synthesis of labelled transition systems (LTSs) for process calculi.
The starting point is a visual technique for modelling the reduction semantics of nominal calculi: processes are mapped into graphs equipped with "interfaces", such that the denotation is fully abstract with respect to the structural congruence. The encoding allows for the reuse of standard graph rewriting theory and tools for simulating the reduction semantics of the calculus, such as the "double pushout" (DPO) approach and its concurrent semantics (which allows for the simultaneous execution of independent reductions)
Graphs with interfaces are just an instance of a cospan category (over the category of graphs). which is amenable to the synthesis mechanism based on "borrowed contexts" (BCs), proposed by Ehrig and Koenig, which are in turn an instance of "relative push outs" (RPOs), originally introduced by Milner and Leifer. The BC mechanism allows for the effective construction of an LTS that has graphs with interfaces as both states and labels, and such that the associated bisimilarity is automatically a congruence.
Since the category of cospans over graphs admits RPOs (as proved by Sassone and Sobocinski), its choice as the domain of the encoding for nominal calculi ensures that the synthesis of an LTS can be performed, and that a compositional observational equivalence is obtained. The talk discusses the LTS distilled by exploiting the encoding of CCS and Mobile Ambients processes.