Search results for "Engineering sciences"

Caractérisation fine du climat en serre expérimentale - Cas de la plateforme 4PMI de l’INRA de Dijon

2019

Les conditions environnementales dans lesquelles sont cultivées les plantes influent grandement surleurs caractéristiques observables, i.e. leur phénotype. Les conditions environnementales d’une serren’étant pas homogènes, elles peuvent induire un biais lors de l’analyse des résultats de phénotypage.Afin de mieux contrôler ce biais, la plateforme « Plant Phenotyping Platform for Plant Micro-organismsInteractions » (4PMI) hébergée par le Centre INRA de Dijon a mis en place un système decaractérisation du climat de chaque plante dans ses serres. Le développement de ce protocole a faitl’objet de ce stage. Dans un premier temps un système de collecte et de gestion des donnéesclimatiques produit…

Finite element multi-scale modeling of the failure mechanisms in a 3D woven composite

2013

International audience

A new constructive method of anisotropic continuous materials behavioral laws based on the theory of invariants

2010

Multi-scale modelling of heterogeneous shell structures

2011

International audience; This paper reviews multi-scale computational homogenisation frameworks for the non-linear behaviour of heterogeneous thin planar shells. Based on a review of some of the currently available methods, a computational homogenisation scheme for shells is applied on to representative volume elements for plain weave composites. The effect of flexural loading on the potential failure modes of such materials is analysed, focusing on the reinforcement-matrix delamination mechanism. The attention is next shifted toward failure localisation in masonry unit cells. Subsequently, a recently developed computational FE2 solution scheme accounting for damage localisation at structura…

Skeleton-Based Multiview Reconstruction

2016

International audience; The advantage of skeleton-based 3D reconstruction is to completely generate a single 3D object from well chosen views. Having numerous views is necessary for a reliable reconstruction but projections of skeletons lead to different topologies. We reconstruct 3D objects with curved medial axis (whose topology is a tree) from the perspective skeletons on an arbitrary number of calibrated acquisitions. The main contribution is to estimate the 3D skeleton, from multiple images: its topology is chosen as the closest to those of the perspective skeletons on the set of images, which means that the number of topology changes to map the 3D skeleton topology to topologies on im…

Equilibres divariants entre la vapeur d'eau et les hydrates solides : Caractérisation de la nature de la solution solide, limites du domaine de divar…

1972

National audience; Nous avons récemment proposé (1, 2) deux modèles thermodynamiques pour les équilibres divariants entre la vapeur d'eau et les hydrates salins solides. Le premier postule l'existence d'une solution solide d'insertion d'eau dans le sel, le second postule l'existence d'une solution solide de substitution entre deux hydrates du sel. Le but de ce travail est d'établir un nouveau critère permettant de distinguer les deux modèles à partir de l'expérience et de délimiter le domaine divariant dans chacun des deux cas. Nous supposerons, sauf mention contraire, que la solution d'insertion obéit à la loi de Henry par rapport à l'eau et que la solution de substitution est idéale. Nous…

Drying process strongly affects probiotics viability and functionalities

2015

International audience; Probiotic formulations are widely used and are proposed to have a variety of beneficial effects, depending on the probiotic strains present in the product. The impact of drying processes on the viability of probiotics is well documented. However, the impact of these processes on probiotics functionality remains unclear. In this work, we investigated variations in seven different bacterial markers after various desiccation processes. Markers were composed of four different viability evaluation (combining two growth abilities and two cytometric measurements) and in three in vitro functionalities: stimulation of IL-10 and IL-12 production by PBMCs (immunomodulation) and…

Conception en technologie CMOS d'un Système de Vision dédié à l'Imagerie Rapide et aux Traitements d'Images

2008

Our work presented in this thesis focuses on the design, testing and implementation of monolithics CMOS image smart sensors : The principle, performance and limitations. The hardware implementation of a vision smart system is the central link. HISIC is High Speed Image Capture with processing at pixel level. An experimental platform for instrumentation and evaluation of retina operators was conducted during this thesis. After a state of the smart sensors and CMOS retinas, the second part is dedicated to the study and design of the pixel image sensor HISIC. Two circuits were realized in CMOS technology. The first identied a new type of photo-detector, and the second, to create a prototype em…

Sélection de bandes pour la visualisation d'images spectrales : une approche basée sur l'étude de saillance

2011

National audience; De nos jours, la plupart des technologies d'affichage numériques sont basées sur le paradigme qu'une combinaison de trois couleurs primaires spécifiques est suffisante pour la reproduction d'une couleur quelconque pour l'oeil humain. Par ailleurs, les dispositifs d'affichage multispectraux ne sont pas encore monnaie courante sur le marché du multimédia. Ainsi, lorsqu'il s'agit de visualiser une image spectrale en couleur, sur un écran traditionnel, seuls trois bandes peuvent être utilisées simultanément, ce qui implique une réduction de dimensionnalité. Cette étape doit permettre la préservation d'un maximum de contenu informatif tout en préservant contrastes et couleurs …

Highly sensitive olfactory biosensors for the detection of volatile organic compounds by surface plasmon resonance imaging

2018

International audience; Nowadays, monitoring of volatile organic compounds (VOCs) is very important in various domains. In this work, we aimed to develop sensitive olfactory biosensors using odorant binding proteins (OBPs) as sensing materials. Three rat OBP3 derivatives with customized binding properties were designed and immobilized on the same chip for the detection of VOCs in solution by surface plasmon resonance imaging (SPRi). We demonstrated that the proteins kept their binding properties after the immobilization under optimized conditions. The obtained olfactory biosensors exhibited very low limits of detection in both concentration (200pM of beta-ionone) and in molecular weight of …