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    A comparison of the characteristic currents method with IEC, ANSI/IEEE, and dynamic simulation procedures for fault calculations

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    Comparisons of power system fault calculation procedures are presented in this paper. The primary method considered in this paper is the characteristic currents method. This calculation procedure has been discussed at length in previous work. It is the purpose of this work to present the extension of the previous work to the general case and compare results obtained using this method with results obtained with methods designed to follow recognized ANSI/IEEE and IEC Standards. Complete time-domain simulation is used as the basis for these comparisons. Sample calculations for a power system containing multiple induction and synchronous machines are provided for demonstration purpose

    Short circuit analysis on a simple power system network. The “characteristic” currents method

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    In this paper a short circuit analysis is performed on a simple power system using the characteristic currents method. Assuming as reference the IEC 909. the characteristic currents method modijes the calculation of the initial symmetrical fault currents corresponding to the 1 cycle symmetrical fault currents discussed in the ANSMEEE Standark C37.010-1979 and C37.13-1981. The approach is based on the correlation between the impedance of each power device and the inverse ofa new parameter which is deJned as the short circuit characteristic current ofthe component itselj: The use of the characteristic currents as parameters make the short circuit analysis easier and allow an immediate erception of what is calculated. Moreover, this method is particularly suitable to be implemented on a spreadsheet program and for the application to an approximate evaluation of the short circuit currents which is helpful during the preliminary design as well as in verifying and testing the electric power systems in buildings. For verijlcalion, comparisons are made between the values calculated with the characteristic currents and appropriate ANSDIEEE Standards

    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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    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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