University of Marne-la-Vallée

About: University of Marne-la-Vallée is a based out in . It is known for research contribution in the topics: Estimator & Context (language use). The organization has 831 authors who have published 1855 publications receiving 55316 citations.

Bounded Palais-Smale mountain-pass sequences

Abstract: Let I (λ, ·), λ e ℝ, be a family of C 1 -functionals having mountain-pass geometry. Under hypotheses which do not ensure that the mountain-pass level c (λ) is a monotone function of λ, it is shown that I (λ) has a bounded Palais-Smale sequence at level c (λ), for almost every λ.

Bubble dynamics relaxation in aqueous foam probed by multispeckle diffusing-wave spectroscopy.

Abstract: We study the bubble rearrangement dynamics in aqueous foam during the passage from liquidlike to solidlike behavior which follows a transient shear deformation that perturbs the bubble packing. The local dynamics is probed using multispeckle diffusing-wave spectroscopy. We show that following the perturbation the average time between rearrangements relaxes exponentially, with time elapsed since the end of the perturbation. The observed scaling of the characteristic relaxation time with perturbation amplitude and foam age is explained by a schematic coarse-grained model based on the scaling state hypothesis.

The network of concepts in written texts

Abstract: Complex network theory is used to investigate the structure of meaningful concepts in written texts of individual authors. Networks have been constructed after a two phase filtering, where words with less meaning contents are eliminated and all remaining words are set to their canonical form, without any number, gender or time flexion. Each sentence in the text is added to the network as a clique. A large number of written texts have been scrutinised, and it is found that texts have small-world as well as scale-free structures. The growth process of these networks has also been investigated, and a universal evolution of network quantifiers have been found among the set of texts written by distinct authors. Further analyses, based on shuffling procedures taken either on the texts or on the constructed networks, provide hints on the role played by the word frequency and sentence length distributions to the network structure.

Mixed monolayers of cationic surfactants and anionic polymers at the air-water interface: Surface tension and ellipsometry studies

Abstract: Equilibrium surface tension measurements have been carried out on mixed solutions of a non- surface active polyelectrolyte (polyacrylamide sulfonate) and cationic surfactants. A strong synergistic lowering of the surface tension is found in the concentration range where no appreciable complexation of surfactant and polymer occurs in the bulk solution (as seen from viscosity measurements). The surface tension decrease does not depend upon the polymer molecular weight, and there is a limited influence of the surfactant chain length. The influence of the degree of charge of the polymer is more important: for small degree of charge, the complexation is less cooperative, and the structure of the surface complex is looser.