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Nombre de programmes trouvés : 5174
Documentaires

le (1h16m28s)

## MARIE COLLIN, INGÉNIEURE DE RECHERCHE AU LABORATOIRE CEMHTI / CNRS ORLEANS : PARCOURS PROFESSIONNEL ET IMPLICATION DANS LA RECHERCHE VIVACE

Après l'obtention d'une licence en physique chimie (spécialité chimie), Marie Collin poursuit ses études en Master Techniques et méthodes analytiques appliquées aux matériaux du patrimoine à l'Université d'Artois située à Lens. Dans ce cadre, elle effectue un stage au C2RMF du Louvre. Elle entame ensuite une thèse portant sur la Géochimie en milieu nanoporeux : application aux verres nucléaires au CEA de Marcoule. Une fois sa thèse soutenue (en 2018), elle rejoint l'équipe de la recherche VIVACE, portée par Nadia Pellerin, au sein du CEMHTI du CNRS dirigé par Catherine Bessada. Elle se penche pendant une année sur la question ...
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Clip pédagogique

le (10m44s)

## Parc immobilier de l’enseignement supérieur et de la recherche : des passoires énergétiques. Il faut agir !

Avec un patrimoine immobilier de plus de 18 millions de m², soit près de 40% du parc immobilier de l’Etat, les établissements d’enseignement supérieur et de recherche ont un rôle crucial à jouer pour atteindre les objectifs nationaux de réduction de la consommation d’énergie et relever le défi de la transition énergétique.
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Conférences

le (1h20m33s)

## C. Araujo - Foliations and birational geometry (Part 2)

In the last few decades, much progress has been made in birational algebraic geometry. The general viewpoint is that complex projective manifolds should be classified according to the behavior of their canonical class. As a result of the minimal model program (MMP), every complex projective manifold can be built up from 3 classes of (possibly singular) projective varieties, namely,  varieties $X$ for which  $K_X$ satisfies $K_X0$. Projective manifolds $X$ whose anti-canonical class $-K_X$ is ample are called Fano manifolds. Techniques ...
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Conférences

le (55m58s)

## H. Guenancia - A decomposition theorem for singular spaces with trivial canonical class (Part 1)

The Beauville-Bogomolov decomposition theorem asserts that any compact Kähler manifold with numerically trivial canonical bundle admits an étale cover that decomposes into a product of a torus, an irreducible, simply-connected Calabi-Yau, and holomorphic symplectic manifolds. With the development of the minimal model program, it became clear that singularities arise as an inevitable part of higher dimensional life. We will present recent works in which a singular version of the decomposition theorem is established.
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Conférences

le (59m9s)

## S. Ghazouani - Isoholonomic foliations of moduli spaces of Riemann surfaces

In this talk, I will introduce families of foliations on the moduli space of Riemann surfaces M_{g,n} which we call Veech foliations. These foliations are defined by identifying M_{g,n} to certain moduli spaces of flat structures and were first defined by Bill Veech. I will try to expose their specificities, both of geometric and dynamical nature. If time permits I will try to illustrate how the case g=1 is linked to certain differential equations whose solutions are special functions of distinguished interest. This is joint work with ...
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Cours magistraux

le (1h18s)

## Bubeck 3/9 - Some geometric aspects of randomized online decision making

This course is concerned with some of the canonical non-stochastic models of online decision making. These models have their origin in works from the 1950's and 1960's, and went through a resurgence in the mid-2000's due to many applications in the internet economy. This course focuses on a set of challenging conjectures around these models from the 1980's and 1990's. We present a unified approach based on a combination of convex optimization techniques together with powerful probabilistic tools, which will allow us to derive state of the art results in online learning, bandit optimization, as well as some classical online ...
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Cours magistraux

le (55m13s)

## Bubeck 4/9 - Some geometric aspects of randomized online decision making

This course is concerned with some of the canonical non-stochastic models of online decision making. These models have their origin in works from the 1950's and 1960's, and went through a resurgence in the mid-2000's due to many applications in the internet economy. This course focuses on a set of challenging conjectures around these models from the 1980's and 1990's. We present a unified approach based on a combination of convex optimization techniques together with powerful probabilistic tools, which will allow us to derive state of the art results in online learning, bandit optimization, as well as some classical online ...
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Conférences

le (41m33s)

## Massoulié - Planting trees in graphs, and finding them back

In this talk we  consider detection and reconstruction of planted structures in Erdős-Rényi random graphs. For planted line graphs, we establish the following phase diagram. In a low density region where the average degree λ of the initial graph is below some critical value λc, detection and reconstruction go from impossible to easy as the line length K crosses some critical value f(λ)ln(n), where n is the number of nodes in the graph. In the high density region λ>λc, detection goes from impossible to easy as K goes from o(\sqrt{n}) to ω(\sqrt{n}), and reconstruction remains impossible so long as K=o(n). We show similar properties for planted D-ary trees. These results are in contrast with the ...
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Conférences

le (42m3s)

## Verzelen - Clustering with the relaxed K-means

This talk is devoted to clustering problems. It amounts to partitionning a set of given points or the nodes of a given graph, in such a way that the groups are as homogeneous as possible. After introducing two random instances of this problem, namely sub-Gaussian Mixture Model (sGMM) and Stochastic Block Model (SBM), I will explain how convex relaxations of the classical $K$-means criterion achieve near optimal performances. Emphasis will be put on the connections between the clustering bounds and relevant results in random matrix theory.
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