Search results for "aléa"

Robust estimation of mean electricity consumption curves by sampling for small areas in presence of missing values

2017

In this thesis, we address the problem of robust estimation of mean or total electricity consumption curves by sampling in a finite population for the entire population and for small areas. We are also interested in estimating mean curves by sampling in presence of partially missing trajectories.Indeed, many studies carried out in the French electricity company EDF, for marketing or power grid management purposes, are based on the analysis of mean or total electricity consumption curves at a fine time scale, for different groups of clients sharing some common characteristics.Because of privacy issues and financial costs, it is not possible to measure the electricity consumption curve of eac…

Spectral properties of random non-self-adjoint operators

2015

In this thesis we are interested in the spectral properties of random non-self-adjoint operators. Weare going to consider primarily the case of small random perturbations of the following two types of operators: 1. a class of non-self-adjoint h-differential operators Ph, introduced by M. Hager [32], in the semiclassical limit (h→0); 2. large Jordan block matrices as the dimension of the matrix gets large (N→∞). In case 1 we are going to consider the operator Ph subject to small Gaussian random perturbations. We let the perturbation coupling constant δ be e (-1/Ch) ≤ δ ⩽ h(k), for constants C, k > 0 suitably large. Let ∑ be the closure of the range of the principal symbol. Previous results o…

Climats tropicaux d'aujourd'hui à demain : variabilité et changements

2008

Present and future tropical climates : their climate variability and their climate changes The oriffttality of tropical climates is re-examined under the light of climate variability and climate change, both present and future . The interannual variability of rainfall is on average larger in the tropics than in the extra-tropics, but it is also spatially more contrasted. Human communities have often responded to this constraint through efficient coping strategies. The regions showing the most variable climate do not necessarily have lower population densities, an indication that in the long run variability is not decisive. However, the recent demographic growth of these regions is often low…

La modélisation complexe en géographie

2013

Arguments pour expliquer la dispersion expérimentale sur le nombre de ruptures de fibres au sein d'un composite obtenue par Emission Acoustique

2013

National audience

"Les aspects financiers des contrats de la commande publique et la prévention des risques des collectivités publiques" in "La certification des compt…

2018

The risks prevention of public authorities may guide the choice of the financial clauses of the public procurement contracts and this tarjet must be maintained during the contracts execution.

La spatialité des dommages et risques environnementaux comme point de convergence entre géographie, écologie et politique

2012

The analysis of complex systems such as those captured by scientific ecology shows that the occurrence of damaging events is difficult to predict. Moreover, most of these unpredictable events will be those with the strongest echoes, giving full meaning to the concept of risk as cross between hazard and vulnerability. Each of these two components of risk has a spatial dimension more or less obvious, and to understand the natural risk, occurrence and spatial extension of the hazard and the vulnerability should be analyzed jointly. Thus, we show that for environmental risk, the question of "where?" posed by the prediction refers certainly to ecological and geographical problems, but also econo…