1,720,958 research outputs found
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
PHOTONIC CRYSTALS
No full textThe present invention relates to two- or three-dimensional photonic
crystals and to methods of making two- or three-dimensional photonic crystals. More specifically, the present invention relates to two- or three-dimensional photonic crystals comprising a fluorinated polymer
Electro-Fenton Degradation of Anionic Surfactants (LAS)
No full textThe degradation of sodium dodecyl benzene sulfonate (LAS), a common industrial and household anionic surfactant, has been investigated by electro-Fenton process. The electrolyses have been performed using an undivided cell equipped with a Ti/RuO2 anode and a commercial graphite-felt to electrogenerate in situ hydrogen peroxide and regenerate ferrous ions as catalyst. The effect of operating conditions such as applied current, catalyst concentration and initial pH has been studied. The experimental results showed that LAS was completely removed by the reaction with •OH radicals generated from electrochemically assisted Fenton’s reaction, and the decay kinetic always follows a pseudo-first-order reaction. The optimum experimental conditions has been obtained at I=200 MA, pH 3 and in the presence of 0.3 mM Fe2+ as catalyst
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
Study of Reliability of SOFC Cathode Impedances at Applied Overpotentials
No full textIn case of measuring separately the behavior of SOFC electrodes the concern of the reliability of impedance results was highlighted by many authors [1-3], especially when overpotentials are applied. A flat thin electrolyte-supported cell in a three-electrode configuration is often investigated, where the RE is deposited in a ring-shape around the WE, being a very convenient geometry from an experimental point of view. The problem arises when the RE is placed in an electrolyte region, which is not equipotential and inaccuracy becomes particularly pronounced when WE and CE are not aligned or have different area specific resistances.
In this work LSM cathodes were investigated on a YSZ electrolyte-supported cell, using an electrolyte 3 mm thick.
Two types of cells were prepared: the first (CellA) according to the geometric requirements suggested in literature [4]: little WE (diameter 3 mm) aligned to the CE and with equal Rp and time constant; RE co-planar around the WE and placed at a distance greater than three- electrolyte thickness from the WE; the second one (CellB) equal to CellA but with a larger WE (diameter 8 mm). Impedance measurements were carried out both in two- and three-electrode configuration, at OCV and under applied overpotentials (Fig. 1).
A preliminary comparison between the results extracted from CellB both at two- and three- electrodes confirms that a thick electrolyte allows extracting suitable three-electrode impedance results in case of OCV conditions. On the other side, when an overpotential is applied, the impedance spectra extracted from CellA and CellB are comparable only at little overpotentials (η < 0.2 V)
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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