1,721,438 research outputs found
ALLNet: Acute Lymphoblastic Leukemia Detection using lightweight convolutional networks
Full text linkMethods for detecting Acute Lymphoblastic (or Lymphocytic) Leukemia (ALL) based on the analysis of blood images are being increasingly researched in the context of Computer Aided Diagnosis (CAD) systems, which help the pathologist in performing in the diagnosis. Within CAD systems, approaches using Deep Learning (DL) and Convolutional Neural Networks (CNN) currently exhibit the highest accuracy in detecting the presence of lymphoblasts, which indicate the possible presence of ALL. Recently, approaches based on histopathological transfer learning have been proposed to increase the accuracy of ALL detection in the presence of databases with a small number of samples, by pretraining the CNN on histopathological data instead of using general-purpose datasets such as ImageNet. However, all the approaches in the literature consider CNN architectures with an extremely high number of parameters, with a learning procedure that is often impractical using mobile devices or without CUDA-enabled architectures. To compensate for these drawbacks, in this paper we propose ALLNet, the first approach in the literature for ALL detection using a lightweight architecture based on fixed binary kernels that replicate the Local Binary Patterns and that uses only ≈1.6% of the parameters of a traditional CNN, at the same time achieving better results in terms of classification accuracy
CONTACTLESS AND LESS-CONSTRAINED PALMPRINT RECOGNITION
Full text linkBiometric systems consist in the combination of devices, algorithms, and procedures used to recognize the individuals based on the characteristics, physical or behavioral, of their persons. These characteristics are called biometric traits.
Nowadays, biometric technologies are becoming more and more widespread, and many people use biometric systems daily. However, in some cases the procedures used for the collection of the biometric traits need the cooperation of the user, controlled environments, illuminations perceived as unpleasant, too strong, or harmful, or the contact of the body with a sensor. For these reasons, techniques for the contactless and less-constrained biometric recognition are being researched, in order to increase the usability and social acceptance of biometric systems, and increase the fields of application of biometric technologies.
In this context, the palmprint is a biometric trait whose acquisition is generally well accepted by the users. Moreover, palmprints can be captured using low-cost devices, and even in the case of elder people or manual workers. However, biometric systems based on the palmprint traditionally use contact-based acquisitions, with pegs used to constrain the position of the hand in a specific way.
For these reasons, this thesis has the objective of researching innovative methods for the contactless and less-constrained recognition of the palmprint. In particular, the researched methods allow to recognize the individuals without the contact of the hand with any surface, and a metric three-dimensional representation is used to eliminate the need for the user to place his hand in a specific position. The originality of the researched techniques allow to perform an accurate biometric recognition, with a focus on the usability, computational speed, and social acceptance of the system. Moreover, the cost of the final device is also taken into consideration. The novelty of the described method, with respect to similar methods in the literature based on contactless three-dimensional acquisitions, resides in the use of an innovative setup, which has a lower cost and captures the images faster.
In particular, innovative multiple view acquisition systems, based on CCD cameras and a led illumination, are designed in order to capture the palmprint samples, and original image processing algorithms are implemented to process the samples. Three-dimensional reconstruction techniques are used in order to achieve a metric representation of the hand, invariant to the pose and orientation. Then, pattern recognition methods are implemented in order to extract and match the distinctive features of the palmprints.
The novel methods researched in this thesis obtained a good recognition accuracy, in many cases superior to the most recent approaches in the literature. Moreover, good results were obtained regarding the computational speed, usability and social acceptance of the considered methods
M. Lutz-Bachmann, Libertà, interesse e responsabilità. Sulla discussione attuale in filosofia morale
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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
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
Touchless palmprint recognition systems
No full textThis book examines the context, motivation and current status of biometric systems based on the palmprint, with a specific focus on touchless and less-constrained systems. It covers new technologies in this rapidly evolving field and is one of the first comprehensive books on palmprint recognition systems. It discusses the research literature and the most relevant industrial applications of palmprint biometrics, including the low-cost solutions based on webcams. The steps of biometric recognition are described in detail, including acquisition setups, algorithms, and evaluation procedures. Constraints and limitations of current palmprint recognition systems are analyzed and discussed. The authors also introduce innovative methods for touchless and less-constrained palmprint recognition, with the aim to make palmprint biometrics easier to use in practical, daily-life applications, and overcome the typical constraints and limitations described. Touchless Palmprint Recognition Systems targets professionals and researchers working in biometrics, image processing and three-dimensional reconstruction. Advanced-level students studying biometrics and computer science will also find this material valuable as a secondary text book or reference
Miscele Idrometano: Applicazione Su Autobus Urbani
No full textLa possibilità di ridurre le emissioni nocive e di CO2, utilizzando le miscele idrogeno-metano (HCNG) ha recentemente attratto l'interesse di produttori di veicoli e operatori del trasporto. Per valutare le potenzialità delle miscele al fine di diminuire le emissioni allo scarico dei motori a combustione interna sono stati condotti diversi esperimenti. Questo lavoro riporta i risultati di prove sperimentali, eseguiti presso il centro ENEA Casaccia, al fine di valutare le prestazioni energetiche ed ambientali di due autobus a (BredaMenarini Vivacity CNG rispettivamente di 8 e 12 m di lunghezza) testati con diverse miscele di metano idrogeno con 5%, 10%, 15%, 20% e 25% di idrogeno in volume utilizzando come riferimento per i test prove effettuate con un gas metano del 100%. Le prove su strada sono state effettuate eseguendo un percorso prefissato, rappresentativo di cicli di guida urbani ed extraurbani e, per la messa a punto del motore termico è stata modificata la mappatura dell’anticipo motore per adattarsi alle variate caratteristiche del combustibile, (minimizzazione dei consumi e non aumento delle emissioni). I bus, quando alimentati con idrometano, grazie ad una maggiore velocità di combustione dell’idrogeno mostrano un miglioramento del rendimento energetico e i miglioramenti sono visibili già con basse percentuali: con un contenuto del 5% di H2 è stato evidenziato un miglioramento di circa il 4% del consumo energetico mentre i miglioramenti massimi si ottengono con una miscela dal 15% al 25%. I test effettuati hanno evidenziato una riduzione di CO2 che è maggiore rispetto a quella calcolabile con la sola sostituzione degli atomi di carbonio con l’idrogeno. Si verifica infatti un effetto leva che porta ad avere per una miscela del 25% diH2 una riduzione del 25% le emissioni di CO2 rispetto al 9% del valore teorico previsto, e questa è la più grande riduzione rilevata nella sperimentazione. CO ed HC hanno valori molto bassi al limite di sensibilità dello strumento di misura utilizzato (HORIBA OBS 1300), mentre gli NOX fino a una miscela del 15% risultavano più bassi rispetto alla configurazione metano al 100%, ma per miscele con maggiore presenza di idrogeno aumentano
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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