1,721,018 research outputs found
Early detection of children with Autism Spectrum Disorder based on visual exploration of images
No full textAutism Spectrum Disorder is a developmental disorder characterized by a deficit in social behaviour and specific interactions such as reduced eye contact and body gestures. Recent advancements in software and hardware multimedia technologies provide the tools for early detecting the presence of this disorder. In this paper we present an approach based on the combined use of machine learning and eye tracking information. More specifically, features are extracted from image content and viewing behaviour, such as the presence of objects and fixations towards the centre of a scene. Those features are used to train a machine learning-based classifier. The obtained results show that the considered features allow to identify children affected by autism spectrum disorder and typically developing ones
Evaluating the effectiveness of image quality metrics in a light field scenario
No full textIn this contribution, an objective metric for quality evaluation of light field images is presented. The method is based on the exploitation of the depth information of a scene, that is captured with high accuracy by the light field imaging system. The depth map is estimated both from the original and impaired light field data. Then, a similarity measure is applied, and a mapping is performed to link the depth distortion with the perceived quality. Experimental test performed by comparing state-of-art metrics with the proposed one, demonstrate the effectiveness of the proposed metric
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Exploiting visual behaviour for autism spectrum disorder identification
No full textIn this contribution, a model for revealing the presence of autism spectrum disorder by exploiting visual information is developed. This condition is characterized by a deficit in social behaviour and nonverbal interactions such as specific facial expressions, reduced eye contact, and body gestures. Advancements in multimedia technologies can help in understanding symptoms for early detection of the disorder. In the proposed model, both the image content and the viewing behaviour are used for defining relevant features to be used in a machine learning-based classifier. A training phase is realized by taking multiple images and scanpaths representing the viewing behaviour of persons affected and not by the disorder. The influence of specific objects in the scene is considered. Finally, the number of fixations towards centre of the scene and duration for which a subject looked at the central area is also considered. A decision tree based classifier is used for training the model. The achieved results show that by taking into account the semantic and image features extracted from content, fixation, and center-bias, it is possible to estimate the presence of autism spectrum disorder. The results obtained in the performed experiments are promising even if they show room for improvement
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Analysis of the influence of human faces for the estimation of salience in omnidirectional images
No full textIn this contribution a study dedicated to understanding the influence of the presence of human faces in a 360° image on human perception is presented. Extensive research on saliency estimation in 2D images has shown that the presence of faces attracts human attention. Following these studies, recent 2D image quality assessment methods exploit face detection systems in their models. The application of these concepts to 360° image is not straightforward. Furthermore, existing literature lacks a comparative study between the performance of face detection algorithms on various types of images (2D, fisheye, and omnidirectional) and how detected faces affect the procedure of saliency estimation. In this direction, we analyze the importance of person faces in a scene, by performing a set of subjective tests. From the performed analysis, it results that, even in 360° images, human faces represent an important factor for image saliency. However, giving equal importance to all the detected faces does not lead to a better saliency estimation. Therefore, in this work, a study on the possible use of the face detector in estimating the salience of the 360° image is performed
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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