1,721,207 research outputs found
Extracting more meaning from CAA results using machine learning
Full text linkThis work describes a novel approach to the problem of extracting knowledge from the results obtained via a CAA system by adopting a Machine Learning paradigm.
The basic idea guiding our research was to investigate the existence of association rules among the topics covered in a course. The data used came from the exams administered to the freshmen in electronic engineering attending the course of Foundation of Computer Science at the University of Ancona. Ten Multiple Choice Questions with four possible answers constituted an exam. Questions have been classified according to the topic covered in a taxonomy derived from the course syllabus. Each question has an absolute weight representing its relative importance inside the curriculum. The data have been filtered by removing low-end and high-end achievers to obtain a subset containing information free from border effects. Each questionnaire has been coded into a vector of features (one for each element of the questions’ taxonomy) representing the student’s answers (right, wrong, not given). The feature vectors are further classified with respect to the final score obtained by the student (poor, average or good) and analysed using C4.5, a classification system based on top-down induction of decision trees that allows generating production rules.
We classified the generated rules into three categories: “straightforward”, “reasonable” and “unexplainable”. Rules are considered “straightforward” when they put in relation topics that we believe are related. “Reasonable” rules put in relation topics that although not being predictable by our experience, may be understood after a deeper analysis of the questions. “Un-explainable” rules put in relation topics that do not appear to be related in any way.
A first interesting result of the method discussed is represented by the so-called “reasonable rules” that may be used to better tune the teaching of the topics that appear to be related
Nuova unità di concezione multiscafo adibita al recupero degli idrocarburi sversati in mare
No full textLa preoccupante ricorrenza e la sempre maggiore gravità degli incidenti che originano sversamenti in mare di idrocarburi dimostrano la necessità di una continua evoluzione di mezzi e tecniche che
consentano di fronteggiare in modo rapido ed efficace il problema, senza produrre ulteriori effetti
collaterali sull’ecosistema marino.
La particolare unità multiscafo descritta nel presente articolo è dimensionata per poter alloggiare a
bordo un innovativo impianto di recupero del petrolio sversato accidentalmente in mare, che sfrutta le
ottime proprietà di assorbimento della lana non trattata (oleofilica e idrorepellente), conosciute fin
dall’antichità ma non ancora mai realmente sfruttate per applicazioni marine atte al disinquinamento
da idrocarburi. Nell’articolo è presentato lo studio di fattibilità del mezzo ideato, di cui si descrivono
le principali caratteristiche geometriche, il profilo operativo e i principali impianti di bordo, con particolare riguardo al sistema di recupero e stoccaggio degli idrocarburi
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
Real-time Monitoring of Cardiac and Respiratory Activities Using a Consumer Wearable Device
No full textVariations 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
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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