Optimal Consensus set for nD Fixed Width Annulus Fitting

International audienceThis paper presents a method for fitting a nD fixed width spherical shell to a given set of nD points in an image in the presence of noise by maximizing the number of inliers, namely the consensus set. We present an algorithm, that provides the optimal solution(s) within a time complexity O(N n+1 log N) for dimension n, N being the number of points. Our algorithm guarantees optimal solution(s) and has lower complexity than previous known methods

Unsupervised, Fast and Precise Recognition of Digital Arcs in Noisy Images

In image processing and pattern recognition, the accuracy of most algorithms is dependent on a good parameterization, generally a computation scale or an estimation of the amount of noise, which may be global or variable within the input image. Recently, a simple and linear time algorithm for arc detection in images was proposed [1]. Its accuracy is dependent on the correct evaluation of the amount of noise, which was set by the user in this former version. In the present work we integrate a promising unsupervised noise detection method [2] in this arc recognition method, in order to process images with or without noise, uniformly distributed or variable within the picture. We evaluate the performance of this algorithm and we compare it with standard arc and circle detection methods based on extensions of the Hough transform

“The psychological evaluation” in a chronic clinical pain: a new figure of paradoxality?

International audienc

Apports de L’Imagerie Pléiades a la Gestion Intégreée des Zones Côtières – Application au Territoire de Thau – [Contributions of Pléiades Satellite Imagery in Integrated Coastal Zone Management – Application to the Thau Territory]

At present and within a context of integrated coastal management, the population growth and increasing land pressure with their subsequent land cover changes on the Thau basin make this territory an important policy issue. In order to cope with the issues at stake the Thau regional authorities have entrusted SMBT from 2006 onwards with the joint development of several planning tools (SCoT, SAGE and Natura 2000 Convention) to conduct an integrated approach to territorial development. The aim of the present paper is to present the methodology used for mapping the initial 2012/2013 land use cover of the Thau basin from Pleiades imagery. This map will be a basic input for the observatory of the Thau territory and support the implementation of planning tools. The methodology was divided into two parts: first, a photo-interpretation approach for artificialised area mapping and evolution monitoring over several years and second, a remote sensing detection approach with the achievement of an object-oriented classification of agricultural and natural environments. This methodology allowed to obtain an up-to-date land use cover according to a 4 level typology adapted from the CORINE land cover nomenclature. This land cover will be updated every second year to help produce assessment and monitoring indicators for the Thau territory

Label Confusion: The Groucho Effect of Uncertain Standards

Labels certify that a product meets some standard for quality, but often consumers are unsure of the exact standard that the label represents. Focusing on the case of ecolabels for environmental quality, we show how even small amounts of uncertainty can create consumer confusion that reduces or eliminates the value to firms of adopting voluntary labels. First, consumers are most suspicious of a label when a product with a bad reputation has it, so labels are often unpersuasive at showing that a seemingly bad product is actually good. Second, label proliferation aggravates the effect of uncertainty, causing the informativeness of labels to decrease rather than increase. Third, uncertainty makes labeling and nonlabeling equilibria more likely to coexist as the number of labels increases, so consumers face greater strategic uncertainty over how to interpret the presence or absence of a label. Finally, a label can be legitimitized or spoiled for other products when a product with a good or bad reputation displays it, so firms may adopt labels strategically to manipulate such information spillovers, which further exacerbates label confusion. Managers can reduce label confusion by supporting mandatory labeling or by undertaking investments to make certain labels "focal." This paper was accepted by Pradeep Chintagunta and Preyas Desai, special issue editors. This paper was accepted by Pradeep Chintagunta and Preyas Desai, special issue editors.marketing, communications, information theory, environment

Racemic phospholipids for origin of life studies

Although prebiotic condensations of glycerol, phosphate and fatty acids produce phospholipid esters with a racemic backbone, most experimental studies on vesicles intended as protocell models have been carried out by employing commercial enantiopure phospholipids. Current experimental research on realistic protocell models urgently requires racemic phospholipids and efficient synthetic routes for their production. Here we propose three synthetic pathways starting from glycerol or from racemic solketal (α, β-isopropylidene-dl-glycerol) for the gram-scale production (up to 4 g) of racemic phospholipid ester precursors. We describe and compare these synthetic pathways with literature data. Racemic phosphatidylcholines and phosphatidylethanolamines were obtained in good yields and high purity from 1,2-diacylglycerols. Racemic POPC (rac-POPC, (R, S)-1-palmitoyl-2-oleoyl-3-phosphocholine), was used as a model compound for the preparation of giant vesicles (GVs). Confocal laser scanning fluorescence microscopy was used to compare GVs prepared from enantiopure (R)-POPC), racemic POPC (rac-POPC) and a scalemic mixture (scal-POPC) of (R)-POPC enriched with rac-POPC. Vesicle morphology and size distribution were similar among the different (R)-POPC, rac-POPC and scal-POPC, while calcein entrapments in (R)-POPC and in scal-POPC were significantly distinct by about 10%