1,720,953 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Avaliação cíclica eletroquímica acelerada de revestimentos inteligentes com microcápsulas de uréia-formaldeído com núcleo contendo agentes de autorreparo
Get PDFA corrosão de metais causa grandes perdas econômicas, representando até 3% do PIB. Técnicas como revestimentos e inibidores químicos são usadas para controlá-la, mas esses revestimentos podem falhar com o tempo. Revestimentos inteligentes, capazes de autorreparo, surgem como uma solução promissora, regenerando danos e restaurando a
proteção. A adição de microcápsulas com núcleos ativos e inibidores de corrosão, como o imidazol, melhora a eficácia desses revestimentos, tornando-os mais resistentes a falhas e aumentando sua durabilidade. Assim sendo, este estudo desenvolve um revestimento inteligente de autorreparo com resina epóxi, microcápsulas com parede de ureia formaldeído e núcleo ativo de epóxi, precursor alcóxido de sílico e imidazol aplicados sobre aço carbono fosfatizado. Dois métodos de síntese de microcápsulas foram testados. Um método de pré-polimerização e um método de polimerização in situ. O método de síntese das microcápsulas foi selecionado de acordo com a morfologia dentre os avaliados neste trabalho, e em seguida, as microcápsulas foram produzidas e tiveram sua composição química avaliada e confirmada através de análise de espectroscopia no infravermelho por transformada de Fourier (FTIR). A técnica de microscopia eletrônica de varredura com fonte de emissão de campo (MEV-FEG) avaliou a morfologia das microcápsulas e seus diâmetros médios, que foram de 4,15 µm, 3,17 µm, 2,56 µm e 2,18 µm para MEp (núcleo ativo de epóxi), MEpIM (núcleo ativo de epóxi e imidazol), MSi (núcleo ativo de precursor alcóxido de silício), e MSiIM (núcleo ativo de precursor alcóxido de silício e imidazol), respectivamente. Nos ensaios eletroquímicos A amostra Ep0, composta apenas por resina epóxi, teve o menor módulo de impedância e ângulo de
fase em comparação com outras amostras produzidas. As amostras contendo microcápsulas apresentaram melhor desempenho anticorrosivo e autorreparo ao longo dos ciclos de ACET. Os valores de impedância no sexto ciclo foram para EpMEp15, EpMEpIm15, MSi15 e MSiIM15 foram |z|0,01= 17960 (Ômega).cm², |z|0,01= 1580 (Ômega).cm² , |z|0,01=
3860 (Ômega).cm² e |z|0,01= 929 (Ômega).cm², respectivamente, superando o revestimento padrão de resina epóxi (|z|0,01= 506 (Ômega).cm²). Em comparação com as amostras contendo apenas resina epóxi e precursor alcóxido de silício, as amostras com núcleo ativo de imidazol reduziram o desempenho eletroquímico do sistema de autorreparo. O ensaio de dureza
indicou aumento da dureza do revestimento com a adição de microcápsulas, indo de H para 2H em comparação a resina epóxi. Os ensaios de impacto direto e reverso revelaram fragilidade dos revestimentos contendo microcápsulas em comparação a resina epóxi, apresentando trincas e desplacamento. Contudo, adição de microcápsulas não afetou a aderência ao substrato metálico. Os testes de névoa salina confirmaram que as microcápsulas melhoraram a resistência à corrosão em comparação com a resina epóxi. Os resultados permitiram concluir que a utilização de um sistema de autorreparo com microcápsulas com núcleo ativo de epóxi, precursor alcóxido de silício e imidazol se demostram promissoras, garantindo maior proteção à corrosão a resina epóxi sobre aço carbono, mesmo quando danificados. [resumo fornecido pelo autor]Metal corrosion causes major economic losses, accounting for up to 3% of GDP. Techniques such as coatings and chemical inhibitors are used to control it, but these coatings can fail over time. Smart, self-healing coatings emerge as a promising solution, regenerating damage and restoring protection. The addition of microcapsules with active nuclei and corrosion inhibitors, such as imidazole, improves the effectiveness of these coatings, making them more resistant to failure and increasing their durability. Therefore, this study develops an intelligent self-healing coating with epoxy resin, microcapsules with urea-formaldehyde wall and active epoxy core, silicon alkoxide precursor and imidazole applied on phosphatized carbon steel. The method of synthesis of microcapsules was selected according to morphology among those evaluated in this work, and then the microcapsules were produced and had their chemical composition evaluated and confirmed through Fourier transform infrared spectroscopy (FTIR) analysis. The scanning electron microscopy technique with field emission source (SEM-FEG) evaluated the morphology of the microcapsules and their mean diameters, which were 4.15 µm, 3.17 µm, 2.56 µm, and 2.18 µm for MEp, MEpIM, MSi, and MSiIM respectively. In the electrochemical tests The Ep0 sample, composed only of epoxy resin, had the lowest impedance modulus and phase angle compared to other samples produced.
Samples containing microcapsules showed better anticorrosive and self-repair performance throughout the ACT cycles. The impedance values in the sixth cycle were for EpMEp15, EpMEpIm15, MSi15 and MSiIM15 were |z|0.01= 17960 (ômega).cm², |z|0.01= 1580 (ômega).cm² , |z|0.01= 3860 (ômega).cm² and |z|0.01= 929 (ômega).cm², respectively, surpassing the standard epoxy resin coating (|z|0.01= 506 (ômega).cm²). Compared to samples containing only epoxy resin and silicon alkoxide precursor, samples with imidazole active core reduced the electrochemical performance of the self-repair system. The hardness test indicates an increase in the hardness of the coating with the addition of microcapsules, going from H to 2H compared to pure epoxy resin. The direct and reverse impact tests revealed fragility of the coatings containing microcapsules compared to pure epoxy resin, presenting cracks and detachment. However, the addition of microcapsules did not affect the adhesion to the metal substrate. Salt spray tests confirmed that the microcapsules improved corrosion resistance compared to pure epoxy resin. The results allowed us to conclude that the use of a self-repair system with microcapsules with an active nucleus of epoxy, precursor silicon alkoxide and imidazole are promising, ensuring greater protection against corrosion of epoxy resin on carbon steel, even after the insertion of a cut exposing the substrate. [resumo fornecido pelo autor]Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, CAPE
Variations on the Author
Get PDF“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
Get PDFWe 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
Get PDFWe 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe 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-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn 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
- …
