Interrelations between processing, orientation and shrinkage in low density polyethylene blown films. III. Orientation of the amorphous phase. [Etude des relations entre mise en forme, orientation et retraction dans des films de polyethylene basse densite realises par soufflage de gaine III. Orientation de la phase amorphe]

International audienceIn this third paper, the orientation of the amorphous phase is deduced from birefringence measurements and from the orientation of the crystalline phase. The amorphous chains tend to be oriented along the transverse direction DT. Consequently, the average orientation of the chains is also, in general, along DT

Influence of mold surface treatments on flow of polymer in injection moulding. Application to weldlines

International audienc

Interrelations between processing, orientation and shrinkage in low density polyethylene blown films. IV. Study of shrinkage Étude des relations entre mise en forme, orientation et rétraction dans des films de polyéthylène basse densité réalisés par soufflage de gaine IV. Étude de la rétraction

International audienceInterrelations between processing, orientation and shrinkage in low density polyethylene blown films. IV. Study of shrinkage. In this last paper, the shrinkage properties of the blown films are investigated. It appears that they are governed by the orientation of the crystalline phase. A good correlation between the cumulated strains during processing and the amounts of shrinkage is found

Planar Polygons Detection in LiDAR Scans Based on Sensor Topology Enhanced RANSAC

International audienceDetecting planar structures in point clouds is a very central step of the point cloud processing pipeline as many Lidar scans, in particular in anthropic environments, present such planar structures. Many improvements have been proposed to RANSAC and the Hough transform, the two major types of plane detection methods. An important limitation however is that these methods detect planes running across the whole scene instead of more localized planar patches. Moreover, they do not exploit the sensor information that often comes with Lidar point cloud (sensor topology and optical center position in particular). In this paper we address both issues: we aim at detecting planar polygons that have a limited spatial extent, and we exploit sensor topology. The latter is used to enhance a RANSAC framework on two aspects: to make seed points selection more local and to define more compact sets of inliers through sensor space region growing