1,720,963 research outputs found
Further applications of continued fractions to series-parallel circuits
Full text linkThe equivalent resistance of any series-parallel circuit can be ex-
pressed and calculated as a continued fraction obtained dividing two
determinants of a tridiagonal square matrix, called continuants. The
author illustrates that the calculation of the voltages or currents using
the divider formulas can also be developed as fractions of continuants.
Furthermore a Matlab code which calculate continuants and continued
fractions is listed
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
Campi e circuiti elettromagnetici
Full text linkTeoria ed esercizi di esame risolti sui campi e circuiti magnetici, induttori, induttori mutuamente accoppiati, azioni meccaniche generate dalle correnti elettriche, elettromagneti
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
Doppi e multi-bipoli
Full text linkRisoluzione delle reti in continua e alternata utilizzando la rappresentazione di circuiti a 2 o n porte. Matrici caratteristiche e trasformazioni di rappresentazione per un doppio bipolo, i circuiti equivalenti, i possibili collegamenti, trasformatore ideale e doppio bipolo induttivo. Studio degli n-poli e multi-bipoli mediante la matrice delle ammettenze indefinita
La trasformata di Laplace: metodi di calcolo alternativi
Full text linkLo scopo di questo testo è quello di presentare nuovi metodi di risoluzione che rendano relativamente semplice il calcolo della trasformata di Laplace anche in casi particolarmente complicati o apparentemente impossibili, che i testi tradizionali non prendono in considerazione.
Si inizia esaminando le potenze della funzioni sin(us)oidali trigonometriche e iperboliche, con esponente superiore a 2. Si riportano poi esempi in cui tali funzioni si moltiplicano per la potenza della variabile temporale t, con esponente non solamente intero e a tale scopo si introduce la funzione gamma di Eulero.
La trattazione prosegue mostrando che il calcolo della trasformata della maggior parte delle funzioni richieste nelle applicazioni si può effettuare considerandole soluzioni particolari di equazioni differenziali, evitando così lo studio dell'integrale di definizione.
Vengono infine presentati esempi di sistemi integro-differenziali, facendo riferimento ai circuiti elettrici, nei quali, a partire dalla funzione di trasferimento, conoscendo il segnale di ingresso si ricava quello di uscita, o viceversa, mediante l'uso delle trasformate
CIRCUITI TRIFASE
Full text linkTeoria ed esercizi risolti da temi d'esame sui circuiti trifase in regime sinusoidale: reti simmetriche equilibrate e non equilibrate; sistemi trifase simmetrici con neutro. Misura di potenze attiva, reattiva, apparente nei sistemi trifase
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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