Search results for "Analyse"
showing 10 items of 1155 documents
Sociologie d'une crise alimentaire : les consommateurs français à l'épreuve de la maladie de la «vache folle»
2008
National audience; Au cours de la dernière décennie, les systèmes alimentaires des pays occidentaux ont été confrontés à une succession impressionnante de crises sanitaires plus ou moins graves. Parmi les alertes récentes, la crise dite de la « vache folle » constitue sans aucun doute l’événement qui a le plus profondément marqué les mémoires individuelles et collectives. Cette crise sanitaire aux répercussions sociales, politiques et économiques multiples a souvent été présentée comme la conséquence de peurs « irrationnelles » des consommateurs. Les données objectives de la crise montrent pourtant que la thèse de la panique ou de la psychose n’est pas fondée. La disproportion apparente de …
Etude par analyse thermique différentielle des tranformations de phases sur l'iodate de lithium
1986
International audience; Lithium iodate (LiIO3) exists at room temperature either as hexagonal (alpha) or tetragonal (beta) crystals. Beta-LiIO3 is stable up to the melting point, whereas alpha-LiIO3 is known to undergo phase transitions. We have studied by differential thermal analysis (DTA) the sequence of phase transitions occurring on powders prepared by different processes. An alpha-LiIO3 powder obtained by grinding a single crystal exhibits the well-known transformations alpha-gamma-beta. A powder obtained by fast evaporation of an aqueous solution transforms directly the alpha to the beta and does not exhibit any intermediate gamma phase. Further, DTA investigations point out that the…
A 3D multispectral integrated acquisition system : acquisition, data coding and compression
2010
We have developed an integrated system permitting the simultaneous acquisition of the 3D shape and the spectral spectral reflectance of scanned object surfaces. We call this system a 3D multispectral scanner because it combines within a stereopair, a multispectral video camera and a structured light projector. We see several application possibilities for a such acquisition system but we want to highlight applications in the field of digital archiving and broadcasting for heritage objects. In the manuscript we first introduce the acquisition system and its necessary calibrations and treatments needed for his use. Then, once the acquisition system is functional, data that are generated are ri…
Visual and acoustic techniques for motorcycle collision warning system with EEG validation
2018
In many countries, motorcyclist fatality rate is much higher than that of other vehicle drivers. Among many other factors, motorcycle rear-end collisions are also contributing to these biker fatalities. Collision detection systems can be used to minimize these fatalities. However, most of the existing collision detection systems do not identify the type of potential hazard faced by motorcyclists. Every collision warning system used a distinctive collision detection technique, which limits its performance and makes it imperative to study its effectiveness. Unfortunately, no such work has been reported in that particular domain for motorcyclists. Therefore, it is important to study the physio…
Şeffaf cisimlerim 3B taranması
2010
Many practical tasks in industry, such as automatic inspection or robot vision, often require scanning of three-dimensional shapes with non-contact techniques. However, transparent objects, such as those made of glass, still pose difficulties for classical scanning techniques. The reconstruction of surface geometry for transparent objects is complicated by the fact that light is transmitted through, refracted and in some cases reflected by the surface. Current approaches can only deal relatively well with sub-classes of objects. The algorithms are still very specific and not generally applicable. Furthermore, many techniques require considerable acquisition effort and careful calibration. T…
Thermal Engine and Climate Change Challenge
2021
Thermal engines have dominated sectors of economy, and particularly transportation. Their current development and state of the art are the results of XXth century priorities related to economy and environment. In the future, thermal engines will face the challenge of emerging technologies in the frame of sustainable mobility and development. After an analysis of functioning principles and perspectives of development, particularly of combustion engines, thermal engines are compared to other realistic scenarios for transports applications in well-to-wheel and life cycle analysis.
Une mesure comparative en didactique des Mathématiques entre une analyse a priori et la contingence
2007
En didactique des Mathématiques, mais plus généralement en sciences humaines, de nombreuses recherches utilisent des analyses qualitatives pour falsifier expérimentalement des hypothèses formulées a priori, c'est-à-dire en amont de la recherche. Une telle approche méthodologique, appliquée à une enquête, s'avère le plus souvent insuffisante pour analyser toutes les variables en jeu dans des phénomènes contingents d'enseignement/ apprentissage, même si dans certains cas (analyse ponctuelle de protocoles, de vidéos, etc.), elle permet de déceler quelques relations intéressantes. Mais si le nombre de sujets devient trop volumineux, l'analyse qualitative ne réussit plus à extraire toutes les re…
L'analyse fractale, un nouvel outil pour l'analyse spatiale des agglomérations urbaines
1997
The fractal approach. A new tool for the spatial analysis of urban agglomerations. Fractal geometry is a new approach for the study of spatial distributions. The basic model is a law of hierarchical distribution corresponding to Pareto's law which is familiar to urban geographers and demographers. The methods of fractal analysis can be used to study the spatial organization of human activities across scales. The regularities and the discontinuities in the distributions can then be identified. These discontinuities can be spatially situated. Applying this concept to urbanized areas has shown that districts can be defined and classified according to their scaling relations, thereby allowing d…
Analyse de la variabilité génétique mitochondriale et chloroplastique de deux espèces du genre Lupinus (L.Albus et L. Mutabilis)
1988
Notice présente dans BelInra (https://belinra.inra.fr/gestion/catalog.php?categ=isbd&id=90015); il s'agit d'un type de produit dont les métadonnées ne correspondent pas aux métadonnées attendues dans les autres types de produit : DISSERTATION; Analyse de la variabilité génétique mitochondriale et chloroplastique de deux espèces du genre Lupinus (L.Albus et L. Mutabilis)
Questions vives pour la géographie de l'intercommunalité
2008
This paper addresses the geographical stakes which animate cooperation between municipalities. This contribution updates work of Guy Baudelle (1996) and Philippe Menerault (1994) by establishing a new panorama of the intercommunality question through the contribution of geographers. The examination of articles being interested in the intercommunality, published in many reviews of geography, enabled us to draw up a synthesis of the concerns of the discipline on historical, identity, organisational and space dimensions of the cooperation between municipalities. In addition to the geographical interest of this approach, the analysis raises a paradox between spatial cutting and the space practi…