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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

    Models for plain concrete fracture analysis using cohesive interfaces

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    O concreto é um material de comportamento quase-frágil na ruptura, desenvolvendo uma zona de processo de fratura relativamente grande na ponta de uma fissura principal, na qual ocorrem fenômenos complexos. Modelos de fratura discretos são adequados para estudar tais fenômenos. Neste contexto, o presente trabalho estuda diferentes modelos de fratura discreta em concreto simples, em situação de modo I puro e modo misto (modo I e modo II, simultaneamente) empregando dois modelos constitutivos da zona coesiva, um acoplado e outro desacoplado. Considerando que a malha de elementos finitos não é adaptada durante a análise, fissuras não coincidem exatamente com as superfícies reais de fratura, resultando em componentes de tração e corte nas interfaces coesivas da frente de fissuração, as quais também não coincidem com os valores reais. Tais componentes devem diminuir com a abertura da fissura. Neste trabalho é demonstrado que apenas o modelo acoplado é capaz de lidar com as componentes espúrias do vetor tensões, e que a variável-chave é o potencial plástico empregado na integração deste vetor. Os modelos apresentados são comprovados por estudos experimentais, no caso de fratura em modo I puro com testes de flexão de vigas a 3 pontos e no caso do modo misto com testes em viga com 1 entalhe e dois entalhes a 4 pontos, viga com entalhe excêntrico ensaiada a 3 pontos e placa com duplo entalhe. Parâmetros do modo II podem ser alterados em uma faixa grande sem alterar visivelmente os resultados, pelo menos nos exemplos testados. Por outro lado, a lei coesiva para metodologia das interfaces coesivas necessita de uma lei de pré e pós-pico. Para o pós-pico, três leis são utilizadas, a saber: lei linear, bi-linear e exponencial. A escolha da lei interfere tanto no comportamento de pós-pico, como no valor de carga máxima a ser alcançado. A região de pré-pico define aberturas e deslizamentos elásticos fictícios, porém necessários para metodologia das interfaces coesivas. Neste trabalho, uma equação é proposta para determinar a lei constitutiva de pré-pico, que elimina efeitos de malha tornando a análise objetiva.Plain concrete behaves as a quasi-brittle material in rupture, developing a relatively large process zone at the crack tip. Complex phenomena occur in this zone. Discrete fracture models are indicated to study such rupture process. In this context, the present work studies different plain concrete fracture models for mode I and mixed mode (coupled mode I and II) using two constitutive models for the cohesive zone: one is a coupled model and the other is uncoupled. Considering that the finite element mesh is not adapted during the analysis, cracks do not coincide exactly with the real fracture surfaces, resulting in components of the traction vector at the cohesive zone that are not coincident with the real values either. Such components must decrease with crack opening. In this work it is demonstrated that only the coupled model is able to deal with the spurious components of the traction vector and that the key variable in this regard is the plastic-potential used in the tractions integration. The presented models are verified by experimental tests. In the case of the pure mode I, threepoint beams are used and in the case of the mixed mode three-point and four-point beams as well as double-notched plates are used. Mode II parameters can be changed in a large range without a noticeable change in results, at least for the tested examples. On the other side, the cohesive law used in the methodology needs a pre-peak and a post-peak relation. For the postpeak, three different shapes are used: linear, bi-linear and exponential. The shape has influence in the overall post-peak behavior of the body, as well as in the peak loading reached. Pre-peak relation defines the fictitious elastic opening and the sliding necessary to complete the description of the cohesive interface methodology. In this work an equation is proposed for the pre-peak constitutive law that eliminates mesh effect problems, turning the analysis objective

    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

    Author Under Sail The Imagination of Jack London, 1893-1902

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    In Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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