1,720,962 research outputs found
A Robust Approach to Characterize the Human Ear: Application to Biometric Identification
Get PDFThe Human ear is a new technology of biometrics which is not yet used in a real context or in commercial applications. For this purpose of biometric system, we present an improvement for ear recognition methods that use Elliptical Local Binary Pattern operator as a robust descriptor for characterizing the fine details of the two dimensional ear imaging. The improvements are focused on features extractions and dimensionalities reductions steps. The realized system is mainly appropriate for identification mode; it starts by decomposing the normalized ear image into several blocks with different resolutions. Next, the local textural descriptor is applied on each decomposed block. A problem of information redundancies is appeared due to the important size of the concatenated histograms of all blocks, which has been resolved by reducing of the histogram’s dimensionalities and by selecting the pertinent information using Haar Wavelets. Finally, the system is evaluated on the IIT Delhi Database containing two dimensional ear images and we have obtained a success rate about 97% for 493 images from 125 persons and about 96% for 793 images from 221 persons
Multimodal Biometric system using Iris and Fingerprint
Get PDFMost real-life biometric systems are still unimodal. Unimodal biometric systems perform person recognition based on a single source of biometric information. Such systems are often affected by some problems such as noisy sensor data, non-universality and spoof attacks. Multibiometrics overcomes these problems. Multibiometric systems represent the fusion of two or more unimodal biometric systems. Recently, multi-modal biometric fusion techniques have attracted increasing attention and interest among researchers, in the hope that the supplementary information between different biometrics might improve the recognition performance in some difficult biometric problems. The small sample biometric recognition problem is such a research difficulty in real-world applications. In this paper, we present a multibiometric recognition system using two types of biometrics Iris, and Finger Print. The fusion is applied at the matching-score level. The experimental results showed that the designed system achieves an excellent recognition rate
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Contribution to texture analysis of bone radiographs for early diagnosis of osteoporosis
No full textL’ostéoporose est une maladie osseuse caractérisée par une perte importante de la masse osseuse et des altérations de la microarchitecture du tissu osseux. Aujourd’hui, en routine clinique, le diagnostic de l’ostéoporose est basé principalement sur une mesure de la densité minérale osseuse qui n’est pas suffisante, car elle doit être accompagnée par une analyse de la qualité de la microarchitecture osseuse. Les travaux présentés dans cette thèse concernent la caractérisation des images de radiographies osseuses pour le diagnostic précoce de l’ostéoporose. Pour ce faire, afin de mieux caractériser la texture osseuse sur radiographie, nous avons introduit une nouvelle technique de prétraitement des données pour réduire les redondances et éliminer le bruit issu des capteurs d’acquisition. Pour la caractérisation, nous avons proposé une nouvelle technique d’analyse inspirée des motifs binaires locaux (Local Binary Patterns, LBP). Le nouveau descripteur, appelé 1DLBP (One Dimensional Local Binary Patterns) s’applique de manière unidimensionnelle. Pour tester l’efficacité de notre approche, nous avons réalisé deux études cliniques où le nouveau descripteur LBP1D est comparé à la méthode classique, LBP afin de classifier des patients ostéoporotiques et des sujets sains. Les pourcentages de classification obtenus ont été améliorés de 72% avec la méthode classique LBP à 91% avec le nouveau descripteur 1DLBP.Osteoporosis is characterized by a significant loss of bone mass and alterations in the microarchitecture of bone tissue. Actually, in clinical routine the diagnosis of osteoporosis is based mainly on measurement of bone mineral density. It turned out that this is not sufficient, it must be accompanied by an analysis of the microarchitecture of the bone to increase the efficiency of diagnosis. This thesis deals with the characterization of images of bone radiographs for the early diagnosis of osteoporosis. To do this, in order to better characterize the texture of bone radiography, we have introduced a new technique for data preprocessing to reduce redundancy and decrease the effect of the noise resulted by the acquisition sensors. For characterization, we propose a new analysis method inspired from the local binary patterns (LBP). The new descriptor called 1DLBP (One Dimensional Local Binary Patterns) applies in one-dimensionally manner. To evaluate the effectiveness of our approach, we conducted two clinical studies where the new descriptor (1DLBP) is compared with the conventional method (LBP) to classify osteoporotic patients and healthy subjects. The classification scores obtained were enhanced by 72% with the conventional LBP descriptor to 91% with 1DLBP descriptor
Contribution à l'analyse de textures de radiographies osseuses pour le diagnostic précoce de l'ostéoporose
No full textL ostéoporose est une maladie osseuse caractérisée par une perte importante de la masse osseuse et des altérations de la microarchitecture du tissu osseux. Aujourd hui, en routine clinique, le diagnostic de l ostéoporose est basé principalement sur une mesure de la densité minérale osseuse qui n est pas suffisante, car elle doit être accompagnée par une analyse de la qualité de la microarchitecture osseuse. Les travaux présentés dans cette thèse concernent la caractérisation des images de radiographies osseuses pour le diagnostic précoce de l ostéoporose. Pour ce faire, afin de mieux caractériser la texture osseuse sur radiographie, nous avons introduit une nouvelle technique de prétraitement des données pour réduire les redondances et éliminer le bruit issu des capteurs d acquisition. Pour la caractérisation, nous avons proposé une nouvelle technique d analyse inspirée des motifs binaires locaux (Local Binary Patterns, LBP). Le nouveau descripteur, appelé 1DLBP (One Dimensional Local Binary Patterns) s applique de manière unidimensionnelle. Pour tester l efficacité de notre approche, nous avons réalisé deux études cliniques où le nouveau descripteur LBP1D est comparé à la méthode classique, LBP afin de classifier des patients ostéoporotiques et des sujets sains. Les pourcentages de classification obtenus ont été améliorés de 72% avec la méthode classique LBP à 91% avec le nouveau descripteur 1DLBP.Osteoporosis is characterized by a significant loss of bone mass and alterations in the microarchitecture of bone tissue. Actually, in clinical routine the diagnosis of osteoporosis is based mainly on measurement of bone mineral density. It turned out that this is not sufficient, it must be accompanied by an analysis of the microarchitecture of the bone to increase the efficiency of diagnosis. This thesis deals with the characterization of images of bone radiographs for the early diagnosis of osteoporosis. To do this, in order to better characterize the texture of bone radiography, we have introduced a new technique for data preprocessing to reduce redundancy and decrease the effect of the noise resulted by the acquisition sensors. For characterization, we propose a new analysis method inspired from the local binary patterns (LBP). The new descriptor called 1DLBP (One Dimensional Local Binary Patterns) applies in one-dimensionally manner. To evaluate the effectiveness of our approach, we conducted two clinical studies where the new descriptor (1DLBP) is compared with the conventional method (LBP) to classify osteoporotic patients and healthy subjects. The classification scores obtained were enhanced by 72% with the conventional LBP descriptor to 91% with 1DLBP descriptor.ORLEANS-SCD-Bib. electronique (452349901) / SudocSudocFranceF
Speed sensorless vector control of induction machine with Luenberger observer and Kalman filter
No full textVariations on the Author
Get PDF“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
Get PDFWe 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
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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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