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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
Influence of forward and backward travelling reflections on the gain and ASE spectrum of EDFAs
No full textOptical reflections at the input of an optical amplifier increase the noise more than those at the output. Measurements with 21 dB gain and 21 dB return lose indicate that an optical isolator at the input improves the noise figure by 3 dB more than one at the output
Variations 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
Performance of an erbium-doped fiber amplifier in a 16-channel coherent broadcast network experiment
No full textAn erbium-doped fibre amplifier was used in a 16-channel coherent broadcast network experiment operating in the wavelength range of 1538.8 to 1540.0 nm. The fibre-to-fibre gain was 22dB and the amplifier dynamic range was 15dB for the entire transmission spectrum. This enabled the distribution of sixteen 155Mb/s signals to one of 256 end-users at a distance of 102 km
Erbium-doped fibre amplifier in a 16-channel coherent broadcast network
No full textIn this paper, we describe the use of an erbium-doped fibre amplifier in a 16-channel coherent broadcast network experiment operating in the wavelength range of 1538.8 to 1540nm. The fibre-to-fibre gain was 22dB and the amplifier dynamic range was 15dB for the entire transmission spectrum. The amplifier was used to amplify sixteen 155Mb/s signals on one output of a 16-by-16 star coupler, allowing a total span loss of 47dB between transmitted and received signals. Satisfactory transmission system performance is obtained for error ratios of 10-9
Performance of erbium-doped fibre amplifier in 16-channel coherent broadcast network
No full textThe performance of an erbium doped fibre amplifier in a 16-channel coherent broadcast network operating at 155 Mbit/s has been experimentally investigated. A fibre-to-fibre gain of 22dB at 1540nm allowed simulation of a network that serves 256 end-users over a distance of 102 km
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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