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    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

    Recherche de photons sombres avec l'experience HPS au JLab

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    The heavy photon search (HPS) experiment in Jefferson Lab (USA) is looking for a new vector gauge boson, called "heavy photon" or "dark photon", in a mass range of 20 MeV to 1000 MeV. Such particle can couple to the standard model photon through kinetic mixing and therefore can be radiated in electron scatterings. Using a high intensity, one to six GeV electron beam sent onto a tungsten target, HPS will look for a narrow resonance above the QED background that would be a signature of a dark photon. HPS will also exploit the fact that for small couplings, this dark photon would also travel a detectable distance before decaying, providing a second signature in the form of a vertex away from the target. In this thesis, I will present the motivations to look for such a dark photon in this particular domain of phase space, then present the HPS spectrometer, with a particular focus on the electromagnetic calorimeter which was a focus of my work. Then, I will present my work using a Monte-Carlo integration to calculate the cross section of the expected background QED processes for the HPS experiment. The final part of my work presented in this thesis will be focused on my data analysis, looking for a bump on the QED background, I carried out using data taken in Spring 2015.L'expérience HPS (Heavy Photon Search) au Jefferson Lab (USA)recherche un nouveau boson de jauge vecteur, nommé "photon lourd" ou "photon sombre", dans une fourchette de masse allant de 20 à 1000 MeV. Une telle particule couplerait avec le photon du modèle standard par effet de "kinetic mixing" et pourrait ainsi être émis par l'intermédiaire d'électrons. En utilisant un faisceau d'électron de haute intensité d’un à six GeV envoyé sur une cible de tungstène, HPS cherche à détecter une fine résonance dans le bruit de fond produit par les processus QED qui serait la signature d'un photon lourd. HPS exploitera aussi le fait qu'à très petit couplages, le photon lourd se désintègrera après une distance détectable, fournissant ainsi une seconde signature sous la forme d'un vertex éloigné de la cible. Dans cette thèse, je présente les motivations pour une telle recherche de photon lourd dans ce domaine spécifique de l'espace de phase, puis je présente le spectromètre HPS, en détaillant en particulier le calorimètre électromagnétique qui a été l'un de mes sujets d'étude. Ensuite, je présente mon travail utilisant une intégration Monte-Carlo pour calculer la section efficace des processus QED attendus dans l'expérience HPS. Finalement, je présente dans cette thèse mon analyse de donnée pour la recherche d'un pic sur le bruit de fond QED dans les données acquises au printemps 2015

    Recherche de photons sombres avec l'experience HPS au JLab

    No full text
    The heavy photon search (HPS) experiment in Jefferson Lab (USA) is looking for a new vector gauge boson, called "heavy photon" or "dark photon", in a mass range of 20 MeV to 1000 MeV. Such particle can couple to the standard model photon through kinetic mixing and therefore can be radiated in electron scatterings. Using a high intensity, one to six GeV electron beam sent onto a tungsten target, HPS will look for a narrow resonance above the QED background that would be a signature of a dark photon. HPS will also exploit the fact that for small couplings, this dark photon would also travel a detectable distance before decaying, providing a second signature in the form of a vertex away from the target. In this thesis, I will present the motivations to look for such a dark photon in this particular domain of phase space, then present the HPS spectrometer, with a particular focus on the electromagnetic calorimeter which was a focus of my work. Then, I will present my work using a Monte-Carlo integration to calculate the cross section of the expected background QED processes for the HPS experiment. The final part of my work presented in this thesis will be focused on my data analysis, looking for a bump on the QED background, I carried out using data taken in Spring 2015.L'expérience HPS (Heavy Photon Search) au Jefferson Lab (USA)recherche un nouveau boson de jauge vecteur, nommé "photon lourd" ou "photon sombre", dans une fourchette de masse allant de 20 à 1000 MeV. Une telle particule couplerait avec le photon du modèle standard par effet de "kinetic mixing" et pourrait ainsi être émis par l'intermédiaire d'électrons. En utilisant un faisceau d'électron de haute intensité d’un à six GeV envoyé sur une cible de tungstène, HPS cherche à détecter une fine résonance dans le bruit de fond produit par les processus QED qui serait la signature d'un photon lourd. HPS exploitera aussi le fait qu'à très petit couplages, le photon lourd se désintègrera après une distance détectable, fournissant ainsi une seconde signature sous la forme d'un vertex éloigné de la cible. Dans cette thèse, je présente les motivations pour une telle recherche de photon lourd dans ce domaine spécifique de l'espace de phase, puis je présente le spectromètre HPS, en détaillant en particulier le calorimètre électromagnétique qui a été l'un de mes sujets d'étude. Ensuite, je présente mon travail utilisant une intégration Monte-Carlo pour calculer la section efficace des processus QED attendus dans l'expérience HPS. Finalement, je présente dans cette thèse mon analyse de donnée pour la recherche d'un pic sur le bruit de fond QED dans les données acquises au printemps 2015

    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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