1,721,019 research outputs found

    Barber M., Field D., Topping P. (1999) The Neolithic flint mines of England

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    Bostyn Françoise. Barber M., Field D., Topping P. (1999) The Neolithic flint mines of England. In: Bulletin de la Société préhistorique française, tome 98, n°1, 2001. pp. 144-145

    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

    Stochastic stability of the inverted pendulum subject to support motion

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    This paper is concerned with the stochastic stability of an inverted pendulum with a point mass at the top and a spring at the base; the bar is massless. The base is subjected to a vertical acceleration A(t) that is supposed to be a Gaussian stochastic process. A line-like structure excited by a vertical ground motion can be idealized in this way. Without simplifying assumptions the study of the stochastic stability gives rise to a non-trivial problem as the equation of motion belongs to the class of damped Mathieu equations. Thus, it is assumed that during the motion the angle of rotation theta remains small so that sin(theta) = theta . In this way, the motion equation assumes the classical form of the second order oscillator, but the excitation is parametric so that there is a possibility of stochastic instability. Among the different definitions of stochastic stability, the almost sure (sample) stability and the stability in the second moments are considered herein. They are compared in the numerical analyses: it is found that they lead to notable differences in the stability boundaries and the almost sure stability is not conservative

    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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