Search results for " Segmentation"
showing 10 items of 462 documents
Neocomian to early Aptian syn-rift evolution of the normal to oblique-rifted North Gabon Margin (Interior and N'Komi Basins).
2009
18 pages; International audience; The North Gabon coastal rift basins consist of a set of 130–150 long-segment asymmetrically tilted half grabens (Interior Basin) and 000–020 short-segment en échelon half grabens (N'Komi Basin) separated by 040–060 major transverse faults. Tectono-sedimentary analysis of field and subsurface data reveals the control exerted by extensional tectonism over continental sedimentation. During Berriasian to early Barremian times, uniform uniaxial 040–060 extension was responsible for the stretching of the brittle upper crust over a 100-km wide domain. During late Barremian–early Aptian times, the main locus of extension stepped westward resulting in severe end-rif…
Optimized Class-Separability in Hyperspectral Images
2016
International audience; Image visualization techniques are mostly based on three bands as RGB color composite channels for human eye to characterize the scene. This, however, is not effective in case of hyper-spectral images (HSI) because they contain dozens of informative spectral bands. To eliminate redundancy of spectral information among these bands, dimensionality reduction (DR) is applied while at the same trying to retain maximum information. In this paper, we propose a new method of information-preserved hyper-spectral satellite image visualization that is based on fusion of unsupervised band selection techniques and color matching function (CMF) stretching. The results show consist…
Quality Factors Influencing Consumer Demand for Small Fruit by Focus Group and Sensory Test
2017
ABSTRACTThe market of berries is a niche of high value in Italy. Small fruit’s healthy properties are well known in the international market, but little is known about the reason for a low commercialization rate of fresh small fruit in Italy. The objective of this study was to assess consumer preferences in Italy for selected berry species. Moreover, the study aims to identify the relevant attributes of berries that affect the demand for this produce according to consumers and to compare these attributes. We assessed relevant attributes affecting the demand for fresh berries for different consumers’ profiles and compared berries’ attributes rankings. The results reveal high concordance betw…
A segmentation algorithm for noisy images
2005
International audience; This paper presents a segmentation algorithm for gray-level images and addresses issues related to its performance on noisy images. It formulates an image segmentation problem as a partition of a weighted image neighborhood hypergraph. To overcome the computational difficulty of directly solving this problem, a multilevel hypergraph partitioning has been used. To evaluate the algorithm, we have studied how noise affects the performance of the algorithm. The alpha-stable noise is considered and its effects on the algorithm are studied. Key words : graph, hypergraph, neighborhood hypergraph, multilevel hypergraph partitioning, image segmentation and noise removal.
“Natural wine” consumers and interest in label information: An analysis of willingness to pay in a new Italian wine market segment
2019
Abstract Increasing public attention to issues of health and environmental sustainability has contributed to a growing consumer demand for “natural” food and drinks. As has been observed, this trend has also affected the wine market, leading to the spread of so-called “natural wine”. According to the literature, consumers who are aware of the social and environmental impact of their consumption choices pay more attention to the information displayed on the label as a tool to reduce the risk associated with their purchase. This study seeks to identify which consumers are willing to pay for natural wine and to understand what information on the label influences their choice. This study is one…
K-nearest neighbor driving active contours to delineate biological tumor volumes
2019
Abstract An algorithm for tumor delineation in positron emission tomography (PET) is presented. Segmentation is achieved by a local active contour algorithm, integrated and optimized with the k-nearest neighbor (KNN) classification method, which takes advantage of the stratified k-fold cross-validation strategy. The proposed approach is evaluated considering the delineation of cancers located in different body districts (i.e. brain, head and neck, and lung), and considering different PET radioactive tracers. Data are pre-processed in order to be expressed in terms of standardized uptake value, the most widely used PET quantification index. The algorithm uses an initial, operator selected re…
A Fast Multiresolution Approach Useful for Retinal Image Segmentation
2018
Retinal diseases such as retinopathy of prematurity (ROP), diabetic and hypertensive retinopathy present several deformities of fundus oculi which can be analyzed both during screening and monitoring such as the increase of tortuosity, lesions of tissues, exudates and hemorrhages. In particular, one of the first morphological changes of vessel structures is the increase of tortuosity. The aim of this work is the enhancement and the detection of the principal characteristics in retinal image by exploiting a non-supervised and automated methodology. With respect to the well-known image analysis through Gabor or Gaussian filters, our approach uses a filter bank that resembles the “à trous” wav…
Automatic detection of hemangiomas using unsupervised segmentation of regions of interest
2016
In this paper we compare the performances of three automatic methods of identifying hemangioma regions in images: 1) unsupervised segmentation using the Otsu method, 2) Fuzzy C-means clustering (FCM) and 3) an improved region growing algorithm based on FCM (RG-FCM). For each image, the starting point of the algorithms is a rectangular region of interest (ROI) containing the hemangioma. For computing the performances of each method, the ROIs had been manually labeled in 2 classes: pixels of hemangioma and pixels of non-hemangioma. The computed scores are given separately for each image, as well as global performances across all ROIs for both classes. The best classification of non-hemangioma…
Analysis of normal human retinal vascular network architecture using multifractal geometry
2017
AIM To apply the multifractal analysis method as a quantitative approach to a comprehensive description of the microvascular network architecture of the normal human retina. METHODS Fifty volunteers were enrolled in this study in the Ophthalmological Clinic of Cluj-Napoca, Romania, between January 2012 and January 2014. A set of 100 segmented and skeletonised human retinal images, corresponding to normal states of the retina were studied. An automatic unsupervised method for retinal vessel segmentation was applied before multifractal analysis. The multifractal analysis of digital retinal images was made with computer algorithms, applying the standard box-counting method. Statistical analyse…
Study of Consumer Preferences in Regard to the Blonde Orange Cv. Washington Navel “Arancia Di Ribera PDO”
2016
Consumers’ attitude and preferences in regard to food ingre- dients, country of origin, social corporate responsibility toward the environment, and work conditions have changed over the last 10 years. Consumers are getting more educated and there- fore more sensitive around cultivation practices in agriculture and food processing, which increases concerns in regard to production practices in agriculture. Several studies have been conducted on consumers’ preferences about quality food, but not with regard to blonde oranges cv. Washington Navel culti- vated in southern Italy. This quality fruit is a niche product that achieved the Protected Designation of Origin (PDO) certifica- tion for high…