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АНАЛІТИЧНИЙ ОПИС ІНДИКАТОРНИХ ДІАГРАМ
Get PDFIntroduction. The disadvantage of presenting indicator diagrams in engine condition monitoring systems is their representation using splines. The structure of polynomials, which describe the links of splines, does not reflect the laws of thermodynamics, mechanics, chemical kinetics and heat transfer, which are the corresponding processes during the operating cycle of the engine. Purpose. To substantiate the structure of the analytical description of the indicator diagram for a two-stroke diesel engine on the basis of piecewise continuous functions. Develop an algorithm for approximating the indicator diagram with a piecewise continuous function using the tools of the DirectSearch package. Results. Finding the numerical values of the parameters of the approximating function is carried out by solving the problem of nonlinear conditional optimization using the method of conjugate directions with orthogonal shift. Processing of test experimental dependences has shown the possibility of finding the indicators of physical and chemical processes of the engine cycle (on the example of a twostroke diesel engine) with satisfactory accuracy according to the indicator diagram. Conclusions. Approximation of indicator diagrams by piecewise continuous functions, which include functions with physical and chemical content, allows for theoretical analysis of the quality of engine cycles. The function proposed for the approximation of the indicator diagram can be considered as a semi-local approximating spline, the links of which have a smooth connection of the order of C0 . Its individual links are described by linear functions, polytropic functions, a function that is a modified derivative of the Vibe function, a function that simulates gas leakage from the tank in the critical mode. Prospects for further research are related to increasing the accuracy of the approximation by increasing the number of units of the piecewise function, which corresponds to the approximation of the indicator diagram with a larger number of polytropic curves. This, in turn, provides a more adequate description of the indicator chart by highlighting the links on which the heat capacity of the working fluid can be considered constant or varying in polynomial dependences.Вступ. Недоліком представлення індикаторних діаграм у системах моніто- рингу стану двигунів є подання їх за допомогою сплайнів. Структура поліномів, якими описуються ланки сплайнів, не відбиває закономірностей термодинаміки, механіки, хімічної кінетики та теплопередачі, за якими відбуваються відповід- ні процеси під час робочого циклу двигуна. Мета. Мета роботи – обґрунтува- ти структуру аналітичного опису індикаторної діаграми для малообертового дизельного двигуна (МОД) на основі кусково-неперервних функцій, розробити алгоритм апроксимації індикаторної діаграми кусково-неперервною функцією за допомогою інструментів пакета DirectSearch. Результати. Знаходження число- вих значень параметрів апроксимуючої функції здійснюється шляхом розв’язання задачі нелінійної умовної оптимізації за допомогою методу спряжених напря- мів з ортогональним зсувом. Обробка тестових експериментальних залежнос- тей показала можливість знаходження за індикаторною діаграмою показників фізичних та хімічних процесів робочого циклу двигуна (на прикладі МОД) із задо- вільною точністю. Висновки. Апроксимація індикаторних діаграм кусково-непе- рервними функціями, до складу яких входять функції, що мають фізичний та хімічний зміст, дає змогу проводити теоретичний аналіз якості робочих циклів двигунів. Запропоновану для апроксимації індикаторної діаграми функцію можна розглядати як напівлокальний апроксимуючий сплайн, ланки якого мають глад- кість стикування порядку С0 . Її окремі ланки описуються лінійними функціями, політропними функціями, функцією, яка є модифікованою похідною від функції Вібе, функцією, що моделює витік газу з резервуара в критичному режимі. Пер- спективи подальших досліджень пов’язані з підвищенням точності апроксимації за рахунок збільшення кількості ланок кусково-неперервної функції, що відпові- дає наближенню індикаторної діаграми більшою кількістю політропних кривих. Це своєю чергою забезпечує більш адекватний опис індикаторної діаграми шля- хом виділення ланок, на яких теплоємності робочого тіла можна вважати ста- лими або такими, що змінюються за поліноміальними залежностями
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
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
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