Chacun des 176 faisceaux du Laser MégaJoule (LMJ) délivrera une énergie de 8 kJ à 351 nm, dans le régime nanoseconde, sur une cible millimétrique. Avant la focalisation, cette énergie est répartie de façon homogène sur une surface carrée de 400x400mm². Ce flux laser est susceptible d’être absorbé par des défauts présents sous la surface des optiques et d’endommager le composant.
Flow and mixing in the small intestine are multi-scale processes. Flows at the scale of the villi (finger-like structures of approximate to 500 mu m length) are poorly understood. We developed a three-dimensional lattice-Boltzmann model to gain insight into the effects of villous movements and the rheology of digesta on flow, mixing and absorption of nutrients at the periphery of the intestinal lumen.
In this paper, a stochastic nonlinear evolution system under Neumann boundary conditions is investigated. Precisely, we are interested in finding an existence and uniqueness result for a system of random heat equation coupled with a Barenblatt's type equation with a multiplicative stochastic force in the sense of Itô. To do so, we investigate in a first step the case of an additive noise through a semi-implicit in time discretization of the system.
Electrical Impedance Tomography (EIT) is an imaging technique with advantages of non-intrusiveness, low-cost and high temporal resolution, which is promising for multiphase flow instrumentation. However, it produces smooth images with low spatial resolution where the interface between phases cannot be distinguished and from which the phase fraction cannot be estimated correctly. In this article, an eigenvalue analysis of EIT raw data is used to estimate the void fraction, i.e.
A simple model is presented for the description of steady uniform shear flow of granular material. The model is based on a stress fluctuation activated process. The basic idea is that shear between two particles layers induces fluctuations in the media that may trigger a shear at some other position. Based on this idea a minimum model is derived and applied to different configurations of granular shear flow.
The transmission of Quantitative Easing to aggregate macroeconomic variables through the yield curve is disentangled in two yield channels: the term premium channel, captured by a term premium series, and the signaling channel, that corresponds to the interest rate expectations counterpart. Both yield components are extracted from a term structure model and plugged into a Structural VAR with Euro Area macroeconomic variables in which shocks are identified using sign restrictions.
We construct a new, comprehensive instrument-level database of sovereign debt for 18 advanced and emerging countries during 1913–46, an eventful period characterized by notoriously high debt levels. This database is thus the first to provide public debt time series with such a high degree of comparability across countries and time.
This paper investigates the sustainability of public finances in the European countries since 2002. We provide evidence of heterogenous behaviors among the EU countries and show that, even if they had been forced to focus their fiscal efforts on correcting the deviations of debt from their ceiling -through a correcting mechanism such as the recent TSCG rule-, this would not necessarily have changed the likelihood that debt and deficits become more sustainable.
La non-stationnarité est caractéristique des phénomènes physiques transitoires. Par exemple, elle peut être engendrée par la variation de vitesse d'un moteur lors d'une accélération. De même, du fait de l'effet Doppler, un son stationnaire émis par une source en mouvement sera perçu comme étant non stationnaire par un observateur fixe.
Why do some societies fail to adopt more efficient institutions? And why do such failures often coincide with cultural movements that glorify the past? We propose a model highlighting the interplay—or lack thereof—between institutional change and cultural beliefs. The main insight is that institutional change by itself will not lead to a more efficient economy unless culture evolves in tandem.