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.

Minerals discovered in paleolithic black pigments by transmission electron microscopy and micro-X-ray absorption near-edge structure

Abstract: Analysis of archeological materials aims to rediscover the know-how of prehistoric men by determining the nature of the painting matter, its preparation mode, and the geographic origin of its raw materials. The preparation mode of the painting matter of the paleolithic rock art apparently consisted of mixing, grinding, and also heat-treatment.

About the Regularized Navier-Stokes Equations

Abstract: The first goal of this paper is to study the large time behavior of solutions to the Cauchy problem for the 3-dimensional incompressible Navier–Stokes system. The Marcinkiewicz space L3,∞ is used to prove some asymptotic stability results for solutions with infinite energy. Next, this approach is applied to the analysis of two classical “regularized” Navier–Stokes systems. The first one was introduced by J. Leray and consists in “mollifying” the nonlinearity. The second one was proposed by J.-L. Lions, who added the artificial hyper-viscosity (−Δ)l/ 2, l > 2 to the model. It is shown in the present paper that, in the whole space, solutions to those modified models converge as t → ∞ toward solutions of the original Navier–Stokes system.

Degradation of diuron by the electro-Fenton process

Abstract: The degradation of the herbicide diuron has been undertaken by electrochemical advanced oxidation in aqueous solution. This process generates catalytically hydroxyl radicals that are strong oxidizing reagents for the oxidation of organic substances. Hydroxyl radicals degrade diuron in less than 10 min. Kinetic results evidence a pseudo-first-order degradation, with a rate constant of reaction between diuron and hydroxyl radicals of 4.8x109 M−1 s−1. Several degradation products were identified by chromatography-mass spectrometry (LC-MS). The mineralization degree of a 1.7x10−4 M diuron solution reached 93% at 1,000 coulombs.

Parameter estimation for a discrete sampling of an intergrated Ornstein-Uhlenbeck process

Abstract: We study the estimation of parameters θ=(μ, σ2) for a diffusion when we observe a discreatization wiht step Δ of the integral To keep computations tractable we focus on the case of an Ornstein–Uhlenberck process, but our results provide informations on how to deal with other processes. We study an efficient estimator θ n based on the Gaussian property of the process and we give an estimator θ n based on Ryden's idea of maximum likehood split data. We compare these different estimators: first we give some numerical results, then we give a theoretical explanations for these results.

Diversity Measurements of a Reconfigurable Antenna With Switched Polarizations and Patterns

Abstract: A reconfigurable parasitic patch array is designed to provide polarization and pattern diversities. The performance of the device is predicted using a commercial simulator including a pin diode modelling and an optimization procedure of the switched loads based on an equivalent flow graph. Measurements of the correlation factor and the diversity gain in an indoor environment are performed with a dedicated platform for two orientations of the antenna.