Search results for "image analysis"
showing 10 items of 153 documents
Impact of environmental factors on grapevine physiology and responsiveness to elicitor-induced resistance against Plasmopara viticola
2012
Imagerie pour les maladies de la vigne
2013
La viticulture est confrontée à des problèmes majeurs dont la lutte contre les maladies cryptogamiques telles que l’oïdium ou la pourriture grise. Elle utilise alors majoritairement des produits phytosanitaires de synthèse susceptibles de poser des problèmes environnementaux et sanitaires, et de favoriser la sélection de souches de microorganismes pathogènes résistantes. Dans le cadre du plan Ecophyto 2018, la recherche de méthodes visant à diminuer, voire à remplacer, les fongicides de synthèse au vignoble, a pris toute sa place. Deux approches peuvent alors être conduites pour répondre à cet objectif : 1) la réduction du nombre de traitements et des doses appliquées et 2) le développement…
Image analysis methods for assessment of H2O2 production and Plasmopara viticola development in grapevine leaves: application to the evaluation of re…
2014
Phenotyping: Case study of legumes plants
2012
International audience; The activities of the GEAPSI group, belonging to the large research unit Agroecology, is devoted to the genetic improvement of legumes important for European agriculture, and focuses on the cultivated species pea (Pisum sativum) and the field bean (Vicia faba). These studies are supported by basic research on a model legume, Medicago truncatula, used for taking advantage of the extensive genomics information available. Some examples will first illustrate how the combination of analytical, non-destructive phenotypical measurements and modelling can improve our understanding of plant functioning, taking as case studies legumes plants. The presentation will then describ…
Approche multi-critère pour la caractérisation des adventices
2022
The objective of this thesis is to develop a way to detect weeds in a field using multispectral images, in order to determine which weeds should be eliminated during the current crop cycle and more particularly at the early stages. The multi-criteria approach focuses on the spatial arrangement, the spec- tral signature, the morphology and the tex- ture of the plants located in the plots. This work proposes a method for selecting the best criteria for optimal discrimination for a given setup. Prior to the extraction of these crite- ria, a set of methods was developed in order to correct the errors of the acquisition de- vice, to precisely detect the vegetation and then to identify within the…
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…
A Robust Multi Stage Technique for Image Binarization of Degraded Historical Documents
2017
International audience; Document image binarization is a central problem in many document analysis systems. Indeed, it represents one of the basic challenges, especially in case of historical documents analysis. In this paper, we propose a novel robust multi stage framework that combines different existing document image thresholding methods for the purpose of getting a better binarization result. CLAHE technique is introduced to significantly enhance contrast in some poor images. The proposed method then uses a hybrid algorithm to partition image into foreground and background. A special procedure is finally applied in order to remove small noise and correct characters morphology. Experime…
Algorithms for the Automated Analysis of Age-Related Macular Degeneration Biomarkers on Optical Coherence Tomography: A Systematic Review
2017
PURPOSE To assess the quality of optical coherence tomography (OCT) grading algorithms for retinal biomarkers of age-related macular degeneration (AMD). METHODS Following a systematic review of the literature data on detection and quantification of AMD retinal biomarkers by available algorithms were extracted and descriptively synthesized. Algorithm quality was assessed using a modified version of the Quality Assessment of Diagnostic Accuracy Studies 2 checklist with a focus on accuracy against established reference standards and risk of bias. RESULTS Thirty five studies reporting computer-aided diagnosis (CAD) tools for qualitative analysis or algorithms for quantitative analysis were iden…
Cluster priors in the Bayesian modelling of fMRI data
2001
Turbo-Roundabout: Case Study of Driver Behavior and Kinematic Parameters of Light and Heavy Vehicles
2019
AbstractThis research compared kinematic and behavior parameters of light and heavy vehicles at turbo-roundabouts. This is of interest because heavy vehicles can influence turbo-roundabout function...