1,721,043 research outputs found
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
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
Computational approaches to multidimensional radiative transfer and the physics of radiative colliding flows
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<p>Two numerical methods for the solution of the multidimensional NLTE radiative transfer problem under optically thick and optically thin conditions for a prescribed density and velocity distribution are presented, along with first applications. The stability of radiative shock waves and the consequences for structure formation are investigated. The first method has been developed for optically thick conditions. A generalized mean intensity approach is used for the solution of the transfer equation, whose advantages are the independence of the convergence properties on the grid spacing and the moderate memory requirements. An equidistant Cartesian grid is used and a first order finite difference scheme, together with upwinding. The rate equation part is solved by standard techniques and iteratively coupled to the transfer part. Sobolev coefficients, adapted to three dimensions, are used for the treatment of optically thick lines. The main difference to other existing methods lies in the solution of the transfer equation. We present extended tests for parts of the corresponding code TR3D as well as for the code as a whole. The second approach has been designed under the simplifying assumption of nebular conditions. The corresponding code D3NEBEL can compute the ionization structure and optically thin, Doppler shifted emission line profiles. The three dimensional structure is caught by a set of one dimensional rays. The one dimensional solver applied to each ray features automatic adaptation of the step size in radial direction, a great number of atomic processes and atomic data, and a consistent temperature computation. In addition, if applicable D3NEBEL is much faster than TR3D. To demonstrate its capabilities for the investigation of binary star systems, D3NEBEL has been applied to several three dimensional model density and velocity distributions of symbiotic binaries. In the third part of this thesis, the stability properties of radiative colliding flows are investigated. One and two dimensional numerical simulations of radiative shock waves have been performed, using Euler equations with a source term to account for radiative energy loss. We show that unstable behavior is rather the rule than the exception. The two dimensional simulations show a subtle interplay between classical hydrodynamical instabilities, like Rayleigh-Taylor, Richtmyer-Meskov, and Kelvin-Helmholtz, the thermal instability of the cooling gas, and thin shell instabilities. These instabilities generate supersonic turbulence in the interaction zone and cause the formation of high density knots and filaments in a otherwise tenuous surrounding. In this way, radiative shock waves may considerably contribute to structure formation, causing, for example, cometary knots in planetary nebula or even the formation of entire stars. The complex behavior of the interaction zone probably puts its stamp on parts of the emitted spectrum from radio to X-ray.</p>
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Computational approaches to multidimensional radiative transfer and the physics of radiative colliding flows
No full textDispelling 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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