Search results for "MODELISATION"

Assessing environmental noise exposure: does the size of the neighbourhood matter?

2013

International audience; In environmental epidemiology, studies rely on the quantification of subject'sexposures in a surface defined as the subject exposure area. For outdoor exposure, this area is often considered as the subject's neighbourhood. But, depending on the authors, the size and the nature of this neighbourhood differs, making difficult to compare results. In order to study the impact of the sampling surface on the noise exposure values affected to a subject, a high definition environmental noise model has been builton a middle-sized French city. Outdoor neighbourhood noise indices were computed at 10,394 residential buildings, using eight different sizes of buffers defined by di…

Geography of production and incomes ?

2018

The idea that a difference exists between territories supported by the creation of wealth and others more focused on their spending was put forward by Laurent DAVEZIES. This author suggests a noticeableopposition between a geography of production and a geography of incomes. If the underlying transfers of income between these territories are supposed to ensure territorial and social cohesion, they would be a burden likely to decrease the efficiency of the most productive territories. It is therefore necessary, he says, to stop « incantations on the theme of territorial cohesion » and to condemn « discriminating policies in favor of territories creating growth ». However, these analyzes suffe…

Modélisation de la dispersion de transgènes à l'échelle de paysages agricoles

2006

Rapport scientifique de fin de contrat. Appel d'offres : impact des OGM

Degradation mechanisms under hydro-thermo-mechanical loads of natural fibers-reinforced biocomposites : application to the development of lightweight…

2018

With the current environmental concerns, research turns to alternative solutions to synthetic fibres. Vegetal fibers appears as good candidates, with good mechanical properties. However, their low durability is a major issue, especially when the composites are exposed to hydro(hygro)thermal loadings.The purpore of this thesis is to analyse and understand the degradation mechanisms when hydro-thermo-mechanical loadings are applied, in order to implement a predictive modelisation of the composite durability.The manufacturing process wasstudied and optimised to produce reproducible and strong composites. Two materials were produced. Their only difference is their volumetric fiber contents (37.…

Radiative surface temperature and convective flux calculation over crop canopies

1988

The analysis presented in this paper aims at a better understanding of the potential role of radiative temperature, as measured by a radiometer over crops, in sensible heat flux calculation. Defining radiative temperature as the mean temperature of the surfaces viewed by the radiometer (leaves and soil surface) and assuming that an Ohm's law type formula can be used to express sensible heat flux as a function of the difference between air temperature and radiative temperature, the aerodynamic resistance which divides this temperature difference has been analytically defined. The parameters which appear in the resistance expression depend essentially on wind velocity and canopy structure but…

Intégration d'une bouche artificielle dans un système de prélèvement Gilson

2007

Estimation des performances, test et contrôle des systèmes cyber-physiques employant des réseaux de communication non idéaux

2020

Wireless technology is a key enabler of the promises of Industry 4.0 (Smart Manufacturing). As such, wireless technology will be adopted as a principal mode of communication within the factory beginning with the factory enterprise and eventually being adopted for use within the factory workcell. Factory workcell communication has particular requirements on latency, reliability, scale, and security that must first be met by the wireless communication technology used. Wireless is considered a non-ideal form of communication in that when compared to its wired counterparts, it is considered less reliable (lossy) and less secure. These possible impairments lead to delay and loss of data in indus…

Optimizing Fuel Consumption and Pollutant Emissions of a Spark Ignition Engine for Eco-driving Applications

2018

VPPC 2018, Vehicle Power and Propulsion Conference, Chicago, ETATS-UNIS, 27-/08/2018 - 30/08/2018; The transportation sector is a major contributor to both air pollution and greenhouse gas emissions. While optimizing fuel consumption reduces CO2 emissions, it can increase fuel-rich operation and cause higher HC and CO emissions. A simplified emissions model is thus introduced in order to account for the impact of air/fuel ratio on both the exhaust concentration of regulated pollutants and the catalyst efficiency. This model is used to solve the eco-driving problem with dynamic programming and a weighted objective function. An emission-centered and a consumption-centered scenario are compare…

A measurement-based channel model for vehicular communications in tunnels

2014

Wireless Communications and Networking Conference (WCNC), 2014 IEEE, Istanbul, TURQUIE, 06-/04/2014 - 09/04/2014; In this paper, we present a new version of the iterative nonlinear least square approximation (INLSA) algorithm for the design of measurement-based channel simulators. The proposed method aims to match the time-variant impulse response (TVIR) of the simulation model to that of the measured channel. The propagation delays are discerned directly from the measurements, whereas the gains, the Doppler frequencies, and the phases are computed iteratively by minimizing a matching error norm. We evaluate the performance of the proposed method in terms of the approximation of the transfe…

Vitesse, accessibilité et étalement urbain ; analyse et application à l'aire urbaine dijonnaise

2003

The set of themes of the city is approached primarily by the means of the residential density. This concept is analyzed from a purely conceptual point of view, then more theoretical (thus making use of rather traditional econometric models: Clark, Newling) for finally being applied to the agglomeration dijonnaise like with its urban surface. One releases the great urban structures thus revealing an intermediate city between the model monocentric and polycentric. The two components are analyzed successively starting from the concept of residential density. Taking as assumption that the cities are dynamic, the second stage is that of urban sprawl out. A first introductory approach attempts to…