L'engagement de jeunes ouvriers et étudiants dans le mouvement contestataire Clermontois en Mai/Juin 68

National audienceA travers l'étude du mouvement contestataire clermontois en mai-juin 68, cet article restitue les modalités et les enjeux de l'engagement d'une jeunesse plurielle tant en milieu étudiant qu'en milieu ouvrier. Il met en lumière les tonalités différentes de la contestation des pouvoirs(politique,patronal,universitaire et même syndical) tout en s'interrogeant sur les clivages générationnels. Il examine les possibilités de jonction entre mouvement étudiant et mouvement ouvrier et tente aussi de repérer les rencontres réelles entre des individus situés dans deux communautés apparemment distincte

Strontium Barium Niobate Thin Films for Dielectric and Electro-Optic Applications

SBN exhibits excellent dielectric non linear properties and one of the largest known Pockels electro-optic coefficient. Thin films of SBN are therefore particularly attractive for their potential use as low voltage electro-optic waveguides or for the realization of electrically-tunable photonic crystals. This chapter proposes an overview of the questions relative to the preparation, dielectric and electro-optic properties of SBN thin films, with a special focus on epitaxial growth in view of electro-optic applications. Experimental results obtained with films prepared by RF magnetron sputtering are presented

Uniform bounds for higher-order semilinear problems in conformal dimension

We establish uniform a-priori estimates for solutions of the semilinear Dirichlet problem \begin{equation} \begin{cases} (-\Delta)^m u=h(x,u)\quad&\mbox{in }\Omega,\\ u=\partial_nu=\cdots=\partial_n^{m-1}u=0\quad&\mbox{on }\partial\Omega, \end{cases} \end{equation} where $h$ is a positive superlinear and subcritical nonlinearity in the sense of the Trudinger-Moser-Adams inequality, either when $\Omega$ is a ball or, provided an energy control on solutions is prescribed, when $\Omega$ is a smooth bounded domain. The analogue problem with Navier boundary conditions is also studied. Finally, as a consequence of our results, existence of a positive solution is shown by degree theory.Comment: Minor correction

Combining Process Guidance and Industrial Feedback for Successfully Deploying Big Data Projects

Companies are faced with the challenge of handling increasing amounts of digital data to run or improve their business. Although a large set of technical solutions are available to manage such Big Data, many companies lack the maturity to manage that kind of projects, which results in a high failure rate. This paper aims at providing better process guidance for a successful deployment of Big Data projects. Our approach is based on the combination of a set of methodological bricks documented in the literature from early data mining projects to nowadays. It is complemented by learned lessons from pilots conducted in different areas (IT, health, space, food industry) with a focus on two pilots giving a concrete vision of how to drive the implementation with emphasis on the identification of values, the definition of a relevant strategy, the use of an Agile follow-up and a progressive rise in maturity

Understanding the catalytic carbonylation of epoxides for the valorization of carbon monoxide

International audienceSmall molecules released as gaseous wastes by the industries, such as CO and CO2, are attractive C1 building blocks for the production of chemicals. They can indeed reduce our dependence on fossil feedstocks. The catalytic insertion of carbon dioxide into epoxides has been developed over the last decades for the production of cyclic and polymeric carbonates, with industrial success. The same strategy can be used for the production of polyester from epoxides and carbon monoxide, possibly released from the production of steel. The catalytic carbonylation of epoxides with gaseous CO leads to $\beta$-lactones and this reaction has attracted a particular attention over the past few years. Yet, only few catalytic systems have been developed, all containing a cobalt carbonyl complex assisted by a Lewis acid. Herein, we disclose a theoretical study to understand the mechanism6 of carbonylation of epoxides using a cobalt catalyst with Lewis acids. The influence of the Lewis acidy on the activity was investigated through various boron compounds. The DFT calculations, linked with a Lewis acidity scale, can thus be used as a guide for the development of a novel catalytic system