Édifice Louis-S.-Saint-Laurent

Architecte concepteur: Pierre Gauvreau; Dates de construction: 1871-1873; Date d'agrandissement: 1913; Connu depuis 1984 sous le nom d'édifice Louis-S.-Saint-Laurent; Loge actuellement un comptoir postal, les bureaux et la bibliothèque du Service des parcs d'Environnement Canada; Hartill Art Associates. ACa-1157.Au premier plan: Porte Prescot

Neurodegenerative diseases and risk factors: A literature review

Degenerative diseases of the central nervous system are significant causes of mortality among elderly people in industrialized countries. For the most part, the causes of these diseases are unknown. It is also very difficult to diagnose this type of disease quickly and accurately. This article reviews the epidemiological research on the principal neurodegenerative disorders, focusing on geographical, hereditary and viral and toxicological exposure correlates. We look in particular at the effect of exposure to toxins as well as the effect that deficiencies of elements such as calcium and selenium could have on the development of these neurological diseases. We also consider the possible protectionist effect of some variables on the development of certain neurological diseases.neurodegenerative diseases epidemiology Alzheimer's disease risk factors environment maladies neurodegeneratives epidemiologie maladie d'Alzheimer facteurs de risque environnement

Global sensitivity analysis for road traffic noise modelling

International audienceRegulatory road traffic noise maps are based on input data that are sometimes incomplete, erroneous or non-existent. When designing them, it is therefore necessary to label and qualify these data by giving priority to certain sources of information and certain parameters over others. Beforehand, a sensitivity analysis of the sound prediction model to these input parameters should be carried out to concentrate efforts on the most influential inputs (either physical or configurational parameters). In this paper, an overall sensitivity analysis of the CNOSSOS-EU model is proposed using the Morris screening method. It is conducted using the open source software Noise Modelling, on a case study of a French city. The analysis is performed on 15 of its input parameters at 14343 receivers. The selection of the parameters and their ranges of variation were chosen to mimic those faced by an operator when producing monthly noise maps. Whether or not to consider diffraction at the horizontal edges appears to be the most influential parameter when estimating the number of people exposed to sound levels above 65 dB(A). However, a finer analysis by receiver shows how the influence of each parameter strongly depends on the source-receiver configuration

Coupling time domain acoustical and mesoscale meteorological models

14th Long Range Sound Propagation Symposium, ANNAPOLIS, ETATS-UNIS, 17-/03/2011 - 18/03/2011In this paper, a coupling approach between a meso-scale meteorological model (Meso-NH) and an acoustic propagation model (TLM) is proposed. Meso-NH (http://mesonh.aero.obs-mip.fr/mesonh/) is the non-hydrostatic mesoscale atmospheric model of the French research community. It intended to be applicable to all scales ranging from large (synoptic) scales to small scales (Large-Eddy Simulation) and its performance for several boundary layer regimes has been tested successfully. In order to use it for acoustic purposes, very fine scale simulations have been carried out to be compared to the Lannemezan 2005 experiment, from which both acoustics and meteorological data are available. It was found necessary to take into account the drag force of tree instead of the classical roughness length approach. This development, and its validation, has been done and finally involves a good agreement between simulation and experiment. The Transmission-Line Matrix (TLM) is a time domain acoustics model which permits to take into account all the principle phenomenon of outdoor acoustic propagation (absorption, diffraction, reflection, refraction,..). Its validation has been first carried out for an homogeneous atmosphere (ground effects, obstacle effects, etc.). Next recent developments have been done to take into account meteorological effects through the effective sound celerity. Those new TLM predictions in inhomogeneous atmosphere are compared with FDTD simulations. Finally, the coupling between Meso-NH and the TLM model is presented. Thus, some comparisons between acoustics measurements and 3D simulations within the framework of Lannemezan-2005 experiment site are presented and discussed

Numerical predictions for environmental acoustics: simulation of atmospheric fields and integration in a propagation model

International audienceOutdoor sound prediction is both a societal stake and a scientific issue. Thus this paper deals with numerical simulations of micrometeorological (temperature and wind) fields for environmental acoustics. This is carried out through new developments in the reference mesoscale meteorological model at Météo-France (Meso-NH). Meso-NH predictions at very low scales (about 1m) including new developments (drag force approach) are validated both numerically and experimentally under stable, unstable and neutral conditions. Then, these information can be used as input data for acoustic models. Our time domain acoustic model is based on Transmission Line Matrix method (TLM). Its development has been done in order to be applied to outdoor sound propagation, i.e. in order to take into account topography, ground impedance, meteorological conditions, etc. The numerical validation of the TLM method by comparison with other models shw the relevance of its use in the context of environmental acoustics. Finally, thanks to these models, simulated noise levels in different propagation conditions were compared to in situ measurements. Satisfying results were obtained regarding the observed phenomena variability. A feasibility study on a more complex experience (LTMS) leads to consider the TLM as an accurate and promising method in the context of environmental acoustics