1,720,957 research outputs found
Análise da influência da adição de resíduos metálicos nas propriedades do concreto autoadensável - CAA
Full text linkThis work aimed to analyze the influence on the mechanical, rheological and durability properties of a Self Compacting Concrete - SCC that had different percentages of sand replaced by metal slag and the simultaneous use of marble powder residue as a filler. To this end, a SCC Mix Reference was developed to meet all parameters of the ABNT NBR 15823: 2017. This SCC-REF was changed with the inclusion of four increasing proportions of metal slag (MS) (25, 37.5, 50 and 75%), then these new concretes were tested, and its properties, both fresh and hardened, were compared. The elaboration of the mix control assumed the principle of particle packing and paste optimization. The SCC-REF had the factor water/cement a / c = 0.35, silica fume SF / cement = 0.06, superplasticized/cement SP / c = 0.008. A new sequence of mixing concrete components in the concrete mixer was adopted in this research, which proved to be very efficient. The paste and mortar tests of the SCC-REF demonstrated the characteristics of a high flowability and moderate viscosity. The SCC-REF achieved all parameters of a fresh and hardened self-compacting concrete where it presented excellent results for parameters such as strength and durability. For the production of the mixtures aces with metal chips, small corrections of SF / c and a / c were necessary in some substitutions. Every SCC -MS mix reached all parameters of a fresh state SCC, with the exception of the SCC -MS 75, which did not reach the parameters of the L box. Comparing the results of all concretes, it can be concluded that the replacement of sand by MS is very viable and with replacement up to 50% does not significantly change any of the properties registered by the SCC-REF in both fresh and hardened state. According to the ABNT NBR 8953:2015 all concretes have achieved resistance to a compressive that classify them as structural and high performance. The splitting tensile strength of every concrete is around 10% of its compressive strengths. The values of the module of elasticity decreased with the increment of the substitution. The SCC -MS 75 presented a module of elasticity 20% lower than the mix REF. The surface hardness of concrete grows up to 37.5 of substitution, above this value, it decreases, but maintains a value equivalent to the SCC -REF. The Absorption A% and void index Iv% of concretes increased with the enhance of the substitution, but their low values indicate a durable concrete. Only the SCC -CM 75 is classified as inefficient. All concretes presented low capillary absorption values. Every concrete presented electrical resistivity at 28 days between 100 and 200 Ω.m. Meaning low probability of corrosion. The SCC -CM75 had a high probability of corrosion.Agência 1Este trabalho propôs analisar a influência nas propriedades mecânicas, reológicas e de durabilidade de um Concreto Autoadensável (CAA) que teve substituição de diferentes porcentagens de areia por cavaco metálico e o uso simultâneo de resíduo pó de mármore como filler. Para tanto, foi desenvolvido um traço referência de CAA, que atendeu a todos os parâmetros da ABNT NBR 15823:2017. Este CAA-REF foi alterado com inclusão de quatro proporções crescentes de cavaco metálico (25, 37,5, 50 e 75%) e então, estes novos concretos foram ensaiados e suas propriedades, tanto no estado fresco quanto no endurecido foram comparadas. A elaboração do traço partiu do princípio de empacotamento de partículas e otimização da pasta. O traço do CAA-REF teve o fator (a/c) água/cimento=0,35, (SA/c) sílica ativa/cimento=0,06, (SP/C) superplastificante/cimento=0,008. Foi adotada nesta pesquisa uma nova sequência de mistura dos componentes do concreto na betoneira que se mostrou muito eficiente. Os ensaios de pasta e argamassa do CAA-REF demonstraram as características de alta fluidez e moderada viscosidade. O CAA-REF atingiu todos os parâmetros de um concreto autoadensável no estado fresco e no estado endurecido em que apresentou excelentes resultados para os parâmetros de resistência e durabilidade. Para produção dos traços com cavacos metálicos houve necessidade de pequenas correções de SA/c e a/c para algumas substituições. Os traços de CAA-CM atingiram todos os parâmetros de um CAA no estado fresco com exceção do CAA-CM 75 que não alcançou os parâmetros da caixa L. Comparando os resultados de todos os concretos pode-se concluir que a substituição de areia pelo cavaco metálico é muito viável e com substituição de até 50% não se altera significativamente nenhuma das propriedades registradas pelo CAA-REF tanto no estado fresco como no endurecido. Segundo a ABNT NBR 8953:2015 todos os concretos atingiram resistência à compressão que os classificam como estrutural e de alto desempenho. A resistência à tração de todos os concretos se encontra em torno de 10% das suas resistências à compressão. Os valores do módulo de elasticidade decresceram com o aumento da substituição. O CAA-CM 75 apresentou módulo de elasticidade 20% menor que do REF. A dureza superficial dos concretos cresce com até 37,5% de substituição, acima deste valor decresce, mas mantendo valor equiparado ao do CAA-REF. A absorção A% e índice de vazios Iv% dos concretos cresceram com o aumento da substituição, mas seus índices baixos os enquadram como concretos duráveis. Apenas O CAA-CM 75 é classificado como deficiente. Todos os concretos apresentaram baixos valores de absorção capilar. Todos os concretos apresentaram resistividade elétrica aos 28 dias entre 100 e 200 Ω.m, significando baixa probabilidade de corrosão. Já o CAA-CM75 apresentou alta probabilidade de corrosão
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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
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