1,720,954 research outputs found
Захисні покриття на основі високоміцних бетонів
Full text linkAs the strength of concrete increases, its fragility also increases, and its plastic deformation properties decrease under short-term and long-term loading, which leads to almost instantaneous destruction of concrete when it reaches its limit state. A solution to this problem can be considered dispersed reinforcement of concrete with fiber, which allows to significantly increase its specific strength, especially in tension and bending, crack resistance, resistance to shock and vibration effects, resistance to abrasion, etc. Dispersed reinforced concretes or fiber concretes include a group of composite materials that include short segments of various fibers (fibers) in a cement matrix. Different types of fibers made of steel, glass, synthetic materials, asbestos, carbon, etc. can serve as fibers. The most common fiber concretes based on Portland cement, reinforced with steel fiber - steel fiber concretes. The surface of the fibers can be profiled, etched and, as an exception, smooth. The amount of fibers introduced into the concrete in most cases ranges from 0.5 to 2% by volume. According to their strength properties, products made using fine-grained fiber concrete (lined pipes, bends, tees, crosses, gutters) withstand loads significantly exceeding 5 MPa and therefore can be widely used to protect equipment from abrasive wear, the effects of aggressive environments and high temperatures, which is confirmed by many years of experience in operating such products in various industries, ensuring an increase in the service life of equipment by 2...6 times. Testing of prototypes of lined pipes showed that their reliability and durability in pressure and gravity pipeline systems increases by 5...10 times compared to electric-welded steel pipes and by 2...3 times compared to high-alloy and bimetallic pipes.З підвищенням міцності бетону росте і його крихкість, знижуються пластично-деформаційні властивості при короткочасному й тривалому навантаженням, що приводить практично до миттєвого руйнування бетону при досягненні ним граничного стану. Варіантом вирішення цієї задачі можна вважати дисперсне армування бетону фіброю, що дозволяє істотно підвищити його питому міцність особливо на розтяг і згин, тріщиностійкість, стійкість до ударних і вібраційних впливів, опір стиранню тощо. До дисперсно-армованих бетонів або фібробетонів належить група композиційних матеріалів, що включають короткі відрізки різних волокон (фібри) у цементній матриці. В якості фібри можуть служити різні типи волокон зі сталі, скла, синтетичних матеріалів, азбесту, вуглецю та ін. Найбільш поширені фібробетони на портландцементі, армовані сталевим волокном – сталефібробетони. Поверхня фібр може бути профільована, оброблена травленням і, як виключення, гладкою. Кількість фібр, що вводяться в бетон, у більшості випадків коливається від 0,5 до 2% по об'єму. За своїми властивостями міцності вироби, виготовлені з використанням дрібнозернистого фібро-бетону (футеровані труби, відводи, трійники, хрестовини, жолоби), витримують навантаження, що значно перевищують 5 МПа і тому можуть широко застосовуватися для захисту обладнання від абразивного зносу, впливу агресивних середовищ і високих температур, що підтверджується багаторічною практикою експлуатації таких виробів в різних галузях промисловості, забезпечуючи збільшення терміну служби обладнання в 2…6 разів. Випробування дослідних зразків футерованих труб показали, що їх надійність і довговічність в напірних і гравітаційних трубопровідних системах підвищується в 5…10 разів в порівнянні з електрозварювальними сталевими трубами і в 2…3 рази в порівнянні з високолегованими і біметалевими трубами
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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