1,721,007 research outputs found

    A new approach to partial discharge detection under DC voltage

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    The continuing development of HVDC power transmission systems presents many problems related to evaluation of the reliability of power system assets [1]-[5]. In this context the identification of insulation defects plays a key role in preventing unexpected failures of electrical components. Partial discharge (PD) measurement is a useful approach to assessing the condition of HV power apparatus and cables. Such measurements are also widely employed for HVAC systems. The inception mechanisms of PD in AC systems are well-known, and measurements are usually performed following the IEC 60270 standard [6]. PD measurements under DC voltage present complexities related to the nature of the phenomenon and the supply conditions [7]. In AC systems phase-resolved-partial-discharge (PRPD) patterns allow assessment of the insulation condition, and provide information on the types of defect present [8]. Such analysis cannot be performed under DC voltage, since each discharge event cannot be related to a phase value. The interpretation of the acquired data therefore requires a different approach

    The Cannabis Spread Throughout the Continents and Its Therapeutic Use in History

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    Historical relevance: Cannabis sativa L. (C. sativa) is a plant whose use as a therapeutic agent shares its origins with the first Far East's human societies. Cannabis has been used not only for recreational purposes, but as a food to obtain textile fibers, to produce hemp paper, to treat many physical and mental disorders. Aim of the study: This review aims to provide a complete assessment of the deep knowledge of the cannabis psychoactive effects and medicinal properties in the course of history covering i.) the empirical use of the seeds and the inflorescences to treat many physical ailments by the ancient Oriental physicians ii.) the current use of cannabis as a therapeutic agent after the discovery of its key psychoactive constituent and the human endogenous endocannabinoid system. Methods: This study was performed through a detailed analysis of the studies on historical significance and medical applications of Cannabis sativa by using international scientific databases, historical and medical books, ancient Greek and Chinese manuscripts translations, library and statistical data from government reports and texts from the National Library of Greece (Stavros Niarchos Foundation), from the School of Health Sciences of the National and Kapodistrian University of Athens (Greece). We selected papers and texts focusing on a historical point of view about the medical importance of the plant and its applications for a therapeutic purpose in the past. Results and conclusion: Through a detailed analysis of the available resources about the origins of C. sativa we found that its use by ancient civilizations as a source of food and textile fibers dates back over 10,000 years, while its therapeutic applications have been improved over the centuries, from the ancient East medicine of the 2nd and 1st millennium B.C. to the more recent introduction in the Western world after the 1st century A.D. In the 20th and 21th centuries, Cannabis and its derivatives have been considered as a menace and banned throughout the world, but nowadays they are still the most widely consumed illicit drugs all over the world. Its legalization in some jurisdictions has been accompanied by new lines of research to investigate its possible applications for medical and therapeutic purposes

    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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