1,720,964 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
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
Metastable structures of Fe-Al multilayers grown by evaporation and magnetron sputtering
No full textThe structural properties of Fe/Al multilayers deposited by evaporation or radio frequency magnetron sputtering on a glass substrate were studied by X-ray diffraction and Transmission Electron Microscopy. It was found that for very small bilayer thickness (e. g., δFe=30 nm + δAl=1$/ nm) deposited with the magnetron sputtering technique, some of the metal is involved in a metastable amorphous phase, which is probably influenced at the interface by the disordered structure of the glassy substrate. On increasing the number of bilayers, the amorphous phase disappears from the X-ray patterns: the metal is mainly in a α-Fe type condition. Furthermore, in similar multilayers grown by thermal evaporation, Transmission Electron Microscopy analyses pointed out the presence of intermetallic Fe3Al. The coherency of these multilayers, measured on the (110) reflection of α-Fe (8 nm), remains essentially unchanged with the number of Fe and Al alternating layers, but features relatable to plastic deformation were also noticed. A correction for disorder effects reveals that the average crystallite size of multilayered samples is in fact larger than 10 nm
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
OXYGEN GAS-SENSING CHARACTERISTICS FOR ZNO(LI) SPUTTERED THIN-FILMS
No full textThe oxygen gas-sensing characteristics of ZnO sputtered thin films, undoped or Li doped, versus their working temperatures are reported in this paper. The Li content and the O/Zn ratio are obtained by measurements of nuclear reaction analysis (NRA) and Rutherford back-scattering (RBS), respectively. The structural properties of ZnO and ZnO(Li) films are studied by means of X-ray diffraction (XRD), the preferential orientation of the thin films is found to be (002). We have measured the variation of the electrical conductance for O2 concentrations between 100 and 2 x 10(5) ppm by means of absorption isotherms at temperatures varying from 400 to 550-degrees-C. The oxygen sensitivity and the response times for these ZnO thin films are reported here; the possible interaction mechanisms of gaseous O2 with the bulk of pure or Li-doped films will also be given
MICROSTRUCTURAL CHARACTERIZATION OF FE-AL THIN-FILMS
No full textThe structural properties of thermally evaporated Al-Fe layers were studied as a function of the aluminium layer thickness delta-Al (taking values of 1, 2 and 4 nm), with an iron layer of constant thickness, delta-Fe = 30 nm. The quality and orientation of the material were examined by X-ray diffraction and transmission electron microscopy. Crystallites of alpha-Fe oriented in the (110) direction were around 7-8 nm in size for any value of delta-Al except near delta-Al = 1 nm where a mostly amorphous iron layer was obtained. It was also verified that a bilayer of composition delta-Al = 2 nm and delta-Fe = 30 nm, twice repeated, led to a two-phase metal system consisting of an amorphous component and crystalline alpha-Fe type material texturized along the (110) direction. The Fe3Al phase was also detected in the bilayer structure with delta-Al = 4 nm
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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