Noise mapping based on participative measurements

The high temporal and spatial granularities recommended by the European regulation for the purpose of environmental noise mapping leads to consider new alternatives to simulations for reaching such information. While more and more European cities deploy urban environmental observatories, the ceaseless rising number of citizens equipped with both a geographical positioning system and environmental sensors through their smartphones legitimates the design of outsourced systems that promote citizen participatory sensing. In this context, the OnoM@p system aims at offering a framework for capitalizing on crowd noise data recorded by inexperienced individuals by means of an especially designed mobile phone application. The system fully rests upon open source tools and interoperability standards defined by the Open Geospatial Consortium. Moreover, the implementation of the Spatial Data Infrastructure principle enables to break up as services the various business modules for acquiring, analysing and mapping sound levels. The proposed architecture rests on outsourced processes able to filter outlier sensors and untrustworthy data, to cross- reference geolocalised noise measurements with both geographical and statistical data in order to provide higher level indicators, and to map the collected and processed data based on web services

Le baby-boom québécois : l’importance du mariage

Le baby-boom est un phénomène marquant du xxe siècle dans la plupart des pays industrialisés. Au Québec, il se distingue parce qu’il combine l’augmentation de la fécondité générale et la baisse de la fécondité des couples mariés : ainsi, le baby-boom a lieu parce que plus de gens se marient et se marient plus tôt, même s’ils ont moins d’enfants que leurs parents. Ce paradoxe a été mis en évidence par Jacques Henripin dans sa monographie du recensement de 1961 sur la fécondité au Canada. Nous utilisons les données rétrospectives du recensement de 1981 afin d’analyser plus finement les comportements de nuptialité des femmes et des hommes pendant le baby-boom en nous concentrant sur les différences entre groupes ethnoreligieux et de niveaux de scolarité. Les transformations les plus importantes consistent en un rajeunissement généralisé de l’âge au mariage et, chez les femmes et les francophones les plus scolarisés surtout, en une augmentation de la propension à se marier. Il s’ensuit que les écarts entre groupes ethnoreligieux et entre niveaux de scolarité diminuent considérablement. Le baby-boom québécois semble donc avoir été causé d’abord et avant tout par le mariage plus précoce dans tous les groupes et l’augmentation de la nuptialité dans certains groupes seulement.The Baby Boom significantly transformed the mid-20th Century demography of most countries in the industrialized world. The Quebec baby boom stands out because during this period the overall fertility increased while the fertility of married couples declined: in short, the baby boom occurred because more people got married and did so at a younger age, even though they had fewer children than their parents. This paradox was first unveiled by Jacques Henripin in his monograph of the 1961 Census on fertility in Canada. We use retrospective data from the 1981 Census to analyze in greater detail the marriage patterns of both men and women during the baby boom, focusing on the differences between ethno-religious groups and levels of education. We find that the most significant changes lie in a younger age at marriage for all and, for women and the highly educated French-Catholics especially, in an increased inclination towards marriage. It follows that both cultural and socio-economic marriage differentials were considerably reduced during the baby boom. The baby boom in Quebec thus appears to have been caused first and foremost by earlier marriages for all and a higher propensity to marry for some

DEUFRABASE : A German-French acoustic database on road pavements

In the framework of a DEUFRAKO (German/French cooperation) project on the Prediction and Propagation of Rolling Noise (PR2RN), it has been proposed to rank the different German and French road pavements with respect to noise for different long distance configurations representative of real road topographies, ground characteristics and meteorological situations. After identifications of those typical 30 configurations, the attenations between a reference point in the near field and several receiving points in the far fields have been computed according to the most relevant and adapted modelling methods currently available. The main goal being the accuracy of the prediction and not the computation time, analytical (ray tracing) and numerical (BEM, Parabolic equation) approaches have been implemented. In the following a technique permitting to estimate day and night LA eq and Lden has been used to classify the various pavements for the whole configurations. All those results have been gathered in a common database DEUFRABASE which will be directly available on the website of the author's Institutes. The paper deals with the description of the ranking procedures, how the database is implemented on the web and how to use it for road traffic noise prediction

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

HARMONOISE project - WP4 experimental campaigns : Comparison among methods to separate road traffic noise from extraneous noise

Inter-noise 2004, 33rd International Congress and Exposition on Noise Control Engineering, PRAGUE, TCHÈQUE, RÉPUBLIQUE, 22-/08/2004 - 25/08/2004In the context of the European Commission funded HARMONOISE Project ("Harmonised, Accurate and Reliable Methods for th EU Directive on the Assessment and Management of Environmental Noise"), four experimental campaigns were carried out from October 2002 until October 2003, in two different sites in France (La Crau and St-Berthevin) and for two different season conditions. The measurements were performed over one or two weeks period and aimed at collecting acoustical data from road and railway traffic produced by a straight four-lane highway traffic and by a rail line, micrometeorological data at several different distances from the line source, traffic counts, impedance variations in space and time, etc. Comparison among different approaches to separate traffic noise from extraneous noise are discussed and compared together in order to verify the validity of each method. The analysis will focus on the manual separation method, the statistical and the pattern recognition approaches through common criteria. The results of the analysis will be discussed and presented in this paper