Chaine 3D interactive

With constant evolution of technology, 3D scanners are providing more and more data with ever greater precision. However, the substantial increase of the data size is problematic. Files become very heavy and can cause problems in data transmission or data storage. Therefore, most of the time, the data obtained by the 3d scanners will be analyzed, processed and simplify; this is called 3D acquisition chain.This manuscript presents an approach which digitize objects dynamically by adapting point density during the acquisition depending on the object complexity, without informations on object shape. This system allows to avoid the use of the classic 3D chain. This system do not calculate a dense points cloud which will be simplify later, but it adapts the points density during the acquisition in order to obtain directly simplified data to the acquisition output. This process allows to reduce significantly processing time.Avec l'évolution constante des technologies, les scanners 3D fournissent de plus en plus de données avec une précision toujours plus grande. Cependant, l'augmentation considérable de la taille des données pose des problèmes, les fichiers deviennent très lourds et il peut en découler des difficultés de transmission ou de stockage. C'est pourquoi, la plupart du temps les données obtenues par les scanners vont être analysées, traitées puis simplifiées ; on parle alors de chaine d'acquisition 3D. Ce manuscrit présente une approche qui permet de numériser les objets de manière dynamique, en adaptant la densité de points dès l'acquisition en fonction de la complexité de l'objet à numériser, et ce sans a priori sur la forme de l'objet. Ce système permet d'éviter de passer par la chaine 3D classique, en ne calculant pas un nuage de points dense qu'il faudra simplifier par la suite, mais en adaptant la densité de points au niveau de l'acquisition afin d'obtenir des données simplifiées directement à la sortie de l'acquisition, permettant ainsi de réduire considérablement le temps de traitement des données

Wood fiber orientation assessment based on punctual laser beam excitation: A preliminary study

International audienceThe EU imposes standards for the use of wood in structural applications. Local singularities such as knots affect the wood mechanical properties. They can be revealed by looking at the wood fiber orientation. For this reason, many methods were proposed to estimate the orientation of wood fiber using optical means, X-rays, or scattering measurement techniques. In this paper, an approach to assess the wood fiber orientation based on thermal ellipsometry is developed. The wood part is punctually heated with a Nd-YAG Laser and the thermal response is acquired by an infrared camera. The thermal response is elliptical due to the propagation of the heat through and along the wood fibers. An experiment is presented to show the capacity of such techniques to assess fiber orientation on wood specimen. In addition, an appropriate algorithm is given to extract the orientation of the ellipse

Automatic measurement of wood fiber orientation and knot detection using an optical system based on heating conduction

In this paper, a new approach to computing the deviation of wood grain is proposed. To do this, the thermal conduction properties of timber are used (higher conduction in the fiber direction). Exciting the surface of the wood with a laser and capturing the thermal conduction using a thermal camera, an ellipse can be observed. Using a method similar to the tracheid effect, it is possible to extract information from this ellipse, such as the slope of grain and the presence of knots. With this method it is therefore possible to extend the mechanical model (assessing the mechanical properties of timber) to take certain singularities into account. Using this approach, the slope of grain can be estimated for any wood species, either hardwood or softwood, which was not possible with the existing tracheid effect.- Conseil Régional de Bourgogne (PARI II) - Projet ANR CLAMEB (ANR-11-RMNP-0015

Des routes et des hommes : la construction des échanges par les itinéraires et les transports

Les circulations humaines façonnent le paysage montagnard, traçant les routes qui permettent de franchir les obstacles, de créer un lien avec la plaine, de développer les activités économiques. Portant sur une diversité de territoires, cet ouvrage nous invite à mieux comprendre comment l’homme a ouvert des passages pour dépasser les frontières naturelles et culturelles des montagnes. La présentation de découvertes archéologiques, l’analyse de sources méconnues, l’étude du rôle de la technique et de la cartographie en dressent un panorama allant de l’Antiquité au xxe siècle. Le Congrès national des sociétés historiques et scientifiques rassemble chaque année universitaires, membres de sociétés savantes et jeunes chercheurs. Ce recueil est issu de travaux présentés lors du 142e Congrès sur le thème « Circulations montagnardes, circulations européennes »

3D chain interactive

Avec l'évolution constante des technologies, les scanners 3D fournissent de plus en plus de données avec une précision toujours plus grande. Cependant, l'augmentation considérable de la taille des données pose des problèmes, les fichiers deviennent très lourds et il peut en découler des difficultés de transmission ou de stockage. C'est pourquoi, la plupart du temps les données obtenues par les scanners vont être analysées, traitées puis simplifiées ; on parle alors de chaine d'acquisition 3D. Ce manuscrit présente une approche qui permet de numériser les objets de manière dynamique, en adaptant la densité de points dès l'acquisition en fonction de la complexité de l'objet à numériser, et ce sans a priori sur la forme de l'objet. Ce système permet d'éviter de passer par la chaine 3D classique, en ne calculant pas un nuage de points dense qu'il faudra simplifier par la suite, mais en adaptant la densité de points au niveau de l'acquisition afin d'obtenir des données simplifiées directement à la sortie de l'acquisition, permettant ainsi de réduire considérablement le temps de traitement des données.With constant evolution of technology, 3D scanners are providing more and more data with ever greater precision. However, the substantial increase of the data size is problematic. Files become very heavy and can cause problems in data transmission or data storage. Therefore, most of the time, the data obtained by the 3d scanners will be analyzed, processed and simplify; this is called 3D acquisition chain.This manuscript presents an approach which digitize objects dynamically by adapting point density during the acquisition depending on the object complexity, without informations on object shape. This system allows to avoid the use of the classic 3D chain. This system do not calculate a dense points cloud which will be simplify later, but it adapts the points density during the acquisition in order to obtain directly simplified data to the acquisition output. This process allows to reduce significantly processing time

Primitives extraction based on structured-light images

International audienceGeometric attributes such as curvature or surface orientation are additional information of the 3D points obtained after the scanning of an object. In the classic 3D chain, characterized by a sequential structure, these information are determined from the dense point cloud (from a 3D scanner). Then, they are used to reduce the amount of information and allows to obtain a simplified model. In this paper, we investigate the possibility to extract some geometric attributes, directly from 2D images obtained by the camera of a structured-light system

Extraction de primitives à partir d'images de lumière structurée

National audienceLes attributs géométriques tels que la courbure ou la normale constituent des informations complémentaires aux points 3D obtenus suite à la numérisation d'une surface ou d'un objet. Dans la chaine 3D classique, présentant une structure séquentielle, ces informations sont déterminées à partir du nuage de points dense (issus par exemple d'un scanner 3D). Par la suite, elles sont utilisées pour diminuer la quantité d'information et permettre ainsi d'aboutir à un modèle simplifié (compressé ou modélisé sous forme de primitives). Dans cet article, nous nous intéressons à la possibilité d'extraire certains des attributs mentionnés plus haut, directement à partir des images 2D obtenues par la caméra d'un système de numérisation par lumière structurée

Estimation de surface de Bézier à partir d'images de lumière structurée dans une optique de compression

National audienceCompression of 3D datas has become a topic of increasing importance over the evolution of scanners. With evolution of technologies, the commercial scanners give more and more data points, which can lead to difficulties in transmission or storage. In most cases, the acquisition does not take into account the final use of the data. While in many cases, this would limit the number of points. In this paper, we propose an approach which simplifies the scatterplot for industrial purposes using Bezier surfaces

Although it is rapidly metabolized in cultured rat hepatocytes, lauric acid is used for protein acylation

This study was designed to examine the metabolic fate of exogenous lauric acid in cultured rat hepatocytes, in terms of both lipid metabolism and acylation of proteins. Radiolabeled [ 1-$^{14}$C] -lauric acid at 0.1 mM in the culture medium was rapidly taken up by the cells ($94.8 \pm 2.2\%$ of the initial radioactivity was cleared from the medium after a 4 h incubation) but its incorporation into cellular lipids was low ($24.6 \pm 4.2\%$ of initial radioactivity after 4 h), due to the high $\beta$-oxidation of lauric acid in hepatocytes ($38.7 \pm 4.4\%$ after the same time). Among cellular lipids, lauric acid was preferentially incorporated into triglycerides ($10.6 \pm 4.6\%$ of initial radioactivity after 4 h). Lauric acid was also rapidly converted to palmitic acid by two successive elongations. Protein acylation was detected after metabolic labeling of the cells with [ 11,12-$^3$H] -lauric acid. Two-dimensional electrophoresis separation of the cellular proteins and autoradiography evidenced the incorporation of radioactivity into 35 well-resolved proteins. Radiolabeling of several proteins resulted from covalent linkage to the precursor [ 11,12-$^3$H] -lauric acid or to its elongation product, myristic acid. The covalent linkages between these proteins and lauric acid were broken by base hydrolysis, indicating that the linkage was of the thioester or ester-type. Endogenous myristic acid produced by lauric acid elongation was used for both protein N-myristoylation and protein S-acylation. Therefore, these results show for the first time that, although it is rapidly metabolized in hepatocytes, exogenous lauric acid is a substrate for the acylation of liver proteins