Search results for "Categorization"
showing 10 items of 199 documents
Selection for multicomponent mimicry: equal feature salience and variation in preferred traits
2016
When should multiple traits on Batesian mimics be selected to resemble corresponding traits on model species? Here, we explore two possibilities. First, features of equal salience to predators may be used to categorize prey, selecting for multicomponent mimicry. Second, if different predators use single yet different traits to categorize prey, multicomponent mimicry may still be selected. We studied how blue tits categorized rewarding and unrewarding artificial prey items that are differentiated by a combination of two color dimensions. Many birds used both color dimensions to make decisions, and overall, the population selected for multicomponent mimicry. However, a subset of birds used on…
Oxidation in wine: Does expertise influence the perception?
2019
International audience; Wines can develop off-odours that depreciate their quality. Among them, oxidation is one of the most prevalent. The main objective of this work was to study the perception of wine oxidation through the categorization of oxidized wines perceived as not-faulty/faulty depending on the expertise of participants. For this purpose, one white wine and one red wine were spiked with three volatile oxidation compounds (acetaldehyde, phenylacetaldehyde and methional) in order to recreate twelve levels of oxidation in a controlled way. Samples were submitted to orthonasal tasting for being categorized by wine experts and novices and coupled to a free description task. Results de…
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.
2D/3D Object Recognition and Categorization Approaches for Robotic Grasping
2017
International audience; Object categorization and manipulation are critical tasks for a robot to operate in the household environment. In this paper, we propose new methods for visual recognition and categorization. We describe 2D object database and 3D point clouds with 2D/3D local descriptors which we quantify with the k-means clustering algorithm for obtaining the Bag of Words (BOW). Moreover, we develop a new global descriptor called VFH-Color that combines the original version of Viewpoint Feature Histogram (VFH) descriptor with the color quantization histogram, thus adding the appearance information that improves the recognition rate. The acquired 2D and 3D features are used for train…
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…
Motivators, barriers and strategies of weight management: A cross-sectional study among Finnish adults.
2018
Abstract Background Weight management (WM) is an ongoing global challenge. The purpose of this study was to analyze motivators, barriers, and strategies of WM among Finnish adults. Methods Data were collected in the ‘KULUMA’ (Consumers at the Weight Management Market) project among 667 community-dwelling adults in Eastern and Central Finland (Kuopio and Jyvaskyla). The self-reported questionnaire collected background information and responses to motivators, barriers, and strategy items. Principal component analysis (PCA) was used to extract components of motivators, barriers, and strategies of WM, along with K-means clustering to categorize the participants. Results About 55% of the respond…
Automated Categorization of Parkinsonian Syndromes Using Magnetic Resonance Imaging in a Clinical Setting
2020
Background Machine learning algorithms using magnetic resonance imaging (MRI) data can accurately discriminate parkinsonian syndromes. Validation in patients recruited in routine clinical practice is missing. Objective The aim of this study was to assess the accuracy of a machine learning algorithm trained on a research cohort and tested on an independent clinical replication cohort for the categorization of parkinsonian syndromes. Methods Three hundred twenty-two subjects, including 94 healthy control subjects, 119 patients with Parkinson's disease (PD), 51 patients with progressive supranuclear palsy (PSP) with Richardson's syndrome, 35 with multiple system atrophy (MSA) of the parkinsoni…
Multivariate statistical analysis of a large odorants database aimed at revealing similarities and links between odorants and odors
2017
International audience; The perception of odor is an important component of smell; the first step of odor detection, and the discrimination of structurally diverse odorants depends on their interactions with olfactory receptors (ORs). Indeed, the perception of an odor's quality results from a combinatorial coding, in which the deciphering remains a major challenge. Several studies have successfully established links between odors and odorants by categorizing and classifying data. Hence, the categorization of odors appears to be a promising way to manage odors. In the proposed study, we performed a computational analysis using odor descriptions of the odorants present in Flavor-Base 9th Edit…
Perception of wine quality according to extrinsic cues: The case of Burgundy wine consumers
2013
International audience; The value consumers put on specific products depends on the information they can get from experience and from the commercial description of the products. For wine, this information derives mainly from tasting (intrinsic factors) and from the packaging of the bottles (extrinsic factors). The main purpose of this work is to compare different methodologies able to disclose the extrinsic factors playing an important role in wine quality perception of consumers. Twenty-four Chardonnay commercial wines were selected according to different criteria such as origin, denomination of origin and information provided in the label or back label. Forty-eight participants living in …
Do typically and atypically developing children learn and generalize novel names similarly: The role of conceptual distance during learning and at te…
2020
International audience; There is a large body of evidence showing that comparison of multiple stimuli leads to better conceptualization and generalization of novel names than no-comparison settings in typically developing (TD) children. By contrast, the evidence regarding this issue remains scarce in children with intellectual disabilities (ID). Children with intellectual disabilities (ID) and TD children matched on mental age with the Raven's coloured progressive matrices were tested in several novel name learning comparison conditions, with familiar objects. We manipulated the conceptual distance between the learning stimuli in the learning phase and between the learning and generalizatio…