1,721,737 research outputs found

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

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    “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

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    We 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

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    We 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

    Author Index

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    Negative impurity ions in liquid He-4

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    We present theoretical results, based on zero-temperature density-functional theory, for the formation and properties of a negative impurity ion in bulk liquid (4)He. We first consider Ca which, due to its very low electron affinity, does not easily form a negative ion in vacuum. We show that a neutral Ca atom in bulk liquid (4)He can easily capture a nearby electron bubble leading to the exothermic formation of a Ca(-) ion trapped inside a spherical cavity of similar to 15 A degrees radius. The Ca negative ion in bulk (4)He turns out to be a metastable state, the lowest-energy configuration being represented instead by a weakly bound Ca(-) ion floating over the nearly unperturbed free surface of liquid (4)He. We have computed the threshold negative pressure at which the trapped Ca(-) ion bubble explodes and we discuss our results in light of recent experimental measurements. We have also considered the possible ion formation in the case of a Ne atom, i.e., an atomic impurity that does not form a negative ion in vacuum. Despite the long-range attraction between the electron bubble and the Ne atom due to polarization forces, in the minimum-energy configuration the electron bubble and the Ne atom rather than merge together remain spatially separated in bulk liquid (4)He, forming a weakly bound state that has no analog in vacuum

    Motion of electrons in liquid He-4

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    We present theoretical results on the stationary-state motion of electron bubbles in liquid (4)He both at zero and negative pressures. As the velocity increases, the moving electron bubble is squeezed along the direction of motion while it expands in the transverse directions. When the electron speed is large enough, as a consequence of this change in shape, a vortical fluid motion is induced around the bubble equator which eventually results in the formation and emission of a quantized vortex ring as a critical velocity is reached. This process occurs at zero pressure and at negative pressures down to similar to-1.2 bar. Below this value, the bubble becomes unstable and explodes as soon as the critical velocity is reached. Our results show that fast-moving electron bubbles explode in the pressure range where unidentified electron objects have been found to explode in recent cavitation experiments

    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We 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
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