1,721,644 research outputs found

    O manto de Arthur Bispo

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    Este texto é o discurso de posse na presidência da Academia Brasileira de Letras, proferido em 14 de dezembro de 2017, no qual o passado e o presente são revisitados, na voz de autores e textos, e o futuro se projeta em desejos e sonhos. O sonho do Brasil como um livro em construção. Um livro de muitos autores, com muitos ângulos, espelhado, onde cada qual se reconheça em suas páginas, como fizeram Lima Barreto e Machado de Assis. Como se fora o manto de apresentação de Arthur Bispo do Rosário. Uma cartografia total. A memória de tudo, em todos.</jats:p

    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

    Modelamento eletromagnético analógico de corpos tabulares em contato e sem contato com o manto

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    In the last three decades, electromagnetic methods are continuing to develop due to their proven usefulness in the search for massive sulfides. In tropical regions, the overburden is usually conducting. However the effect of this conducting layer is seldon taken into account while interpretating the EM data. this can cause considerable interpretation erros. In this work, we considered the overburden in-contact and not in-contact with the underlying conductor. Reduced scale model experiments were carried out to study the effects of the overburden on the EM anomalies of inclined tabular like bodies. With this objective, response parameters of the conductor and the overburden were varied. The target-conductor is represented in the model experiments by stainless steel sheets. These sheets are, larg compared the coil separation in order to simulated the behavior of a half-plane. The overburden is simulated by a conducting solution. To represented the case of a conductive-overburden the model is placed in galvanic contact with the solution. In case of the inductive-overburden the model is coupled to the overburden only inductively and did not have a galvanic contact. This situation is attained by keeping the model 1) totally out of the solution, and 2) partially in the solution but the model is covered by a resistive film to avoid the galvanic contact with the solution. In the presence of inductive-overburden, the anomalies are slightly attenuated. In the quadrature component the profile is inverted and an extra-peak appear in the case of low dipping models at higher induction numbers of the overburden and the model. Also the anomaly suffers a clockwise rotation which is intense for higher induction number of the conductor. Therefore, in the presence of an inductive-overburden the conductor appears to be more conducting and at higher depth than it really is. In the presence of a conductive-overburden, the anomaly amplitude are slightly enhanced and suffer an anticlockwise phase rotation, which is more intense at the lower induction number of the conductor. However, the other effects in the quadrature component, like the inversion and an appearance of the extra-peak, are similar to that of the inductive-overburden. Due to these effects of the conductive-overburden, the conductor appears to be at a shallower depth and less conducting than it actually is. These modifications in anomalies are caused by: a) The primary and secondary EM fields suffering attenuation and phase rotation when passing through a conducting overburden, b) an inductive interaction between the induced currents in the conductor and the overburden, and also, c) a redistribution of the currents in the overburden when the conductor is placed in it. In case of a conductive-overburden, currents are channeled in the conductor which is in galvanic contact with the less conducting overburden. On the other hand when a conductor covered with a resistive film is placed in the conducting solution, the currents are displaced and they crowd in the solution next to the boundary of the resistive film.CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorNas últimas três décadas os métodos eletromagnéticos vem se desenvolvendo satisfatoriamente em função da aplicabilidade na prospecção de corpos de sulfetos maciços. Em regiões de climas tropicais, normalmente o manto de intemperismo apresenta-se condutivo. E este, na maioria das vezes, não é levado em conta na prospecção eletromagnética, causando portanto erros consideráveis de interpretações. Neste trabalho consideramos o manto de intemperismo em contato e sem-contato com o corpo condutor. Com o objetivo de estudar os efeitos dos mantos sobre anomalias EM de corpos tabulares inclinados, foram feitos vários experimentos utilizando modelamento analógico em escala reduzida, admitindo-se diferentes parâmetros de resposta para o corpo e o manto. Para simular o corpo foram utilizadas placas de aço inoxidável com as dimensões suficientemente grande em relação ao espaçamento entre as bobinas, de tal modo que simulassem um semi-plano. Para simular o manto foi utilizado uma solução de sais, sendo que para o caso de manto-condutivo, o corpo foi colocado em contato galvânico com a solução. Para o manto-indutivo foi considerado sem-contato galvânico, de tal forma que o corpo e o manto fossem acoplados apenas indutivamente. Onde 1) o corpo foi colocado totalmente sem contato com o manto 2) o corpo foi revestido por uma película resistiva e colocado em contato com o manto. Com a presença de manto-indutivo, observamos que a amplitude dos perfis é levemente atenuada. Além disso, observamos na quadratura a reversão e o aparecimento de um pico-extra nas inclinações do corpo θ≤60º e nos valores de número de indução αc≥78.16 e αm≥0.5 respectivamente do corpo e do manto. E a rotação de fase se dava no sentido horário, sendo mais intensa para altos valores de número de indução do corpo. No manto-indutivo o corpo parece estar a uma profundidade maior que a verdadeira, e ser mais condutivo do que realmente é. Com manto-condutivo, observamos que as amplitudes dos perfis são ligeiramente acrescidos assim como, a rotação de fase se dava no sentido anti-horário sendo mais intensa para pequenos valores de número de indução do corpo. Os demais efeitos tais como reversão na quadratura e presença de pico-extra ocorrem de modo análogo ao ocorrido no caso de manto-indutivo. No manto-condutivo, o corpo parece estar a uma profundidade inferior à verdadeira e ser menos condutivo. As anomalias EM são ligeiramente modificadas em função da rotação de fase e atenuação de amplitudes que ocorrem nos campos primário e secundário quando atravessam o manto, e também em consequência da interação indutiva de corrente induzida entre corpo e manto. Além disso ocorre a redistribuição de corrente no manto devido à presença de corpo dentro do manto. No manto-condutivo as correntes são canalizadas dentro do corpo que está em contato galvânico com o manto, enquanto no manto-indutivo ocorre um desvio de corrente, devido à película resistiva que envolve o corpo

    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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