1,720,979 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
Influence of snow microstructure and properties on the grip of winter tyres
Get PDFThe friction of tyres on roads has been of practical importance for many years with
nearly 80% of terrestrial traffic making use of rubber tyres. Tyres provide the grip
required for vehicle acceleration, braking and cornering. In order for a tyre to grip on a
snow covered surface friction mechanisms such as “ploughing”, (where sharp tread block
edges dig into and break bonds between the snow grains) and fluid film lubrication must
be considered. These are not present when a tyre interacts with tarmac. In addition
metamorphism of the snow over time can result in variations of the structure and
mechanical properties, this can occur rapidly especially when dealing with temperatures
close to snows melting point.
When full car-scale outdoor testing is carried out the snow conditions cannot be
controlled and vary daily. This means the snow properties must be measured every day
so that any observed variations in friction can be attributed to the tyres rather than
the snow. At present the simple measurements being carried out on the snow tracks
have not proved sufficient to pick up on the variations in the snow. This leads to
inconsistent results: one tyre behaves differently on two different days, even though the
snow was measured to be the same. This has resulted in the need for further study of
the way snow variations influence the grip of winter tyres.
The primary aim of this study is to identify which snow properties contribute to the
friction of tyres on snow and be able to estimate the friction from measurements of snow
properties. This work is the first comprehensive study to combine: multiple snow
properties, microstructure characterisation, measurement of friction behaviour and
different snow (both artificial and natural).
In order to study the way snow affects the grip of winter tyres, methods of
manufacturing artificial snow with consistent mechanical properties and microstructure
are used. A method of blending ice chips (a solid state fracturing process) and
compressing the resulting snow to form a test track was developed during a previous
PhD carried out in our group. An alternate snow microstructure was created by using
an established process of creating snow by vapour deposition. The process was simplified
and downscaled, the resulting snow consisted of large dendritic grains, very different to
the blended ice chips. Both snows were pressed in identical manners to create snow
testing tracks. In addition, natural snow collected from the field was tested to compare
with the artificial snow.
In order to investigate how the variations in the snow affected the friction of tyres
extensive testing was carried out in a cold room using a linear tribometer, using
procedures established in previous studies. Two analytical rubber samples were used to
investigate the friction, a rounded edge sample and a siped sample. Testing was carried
out at -10°C at speeds of 0.01m/s, 0.1m/s and 1m/s.
A significant part of this PhD involved the development of new methods and equipment
which have not been used to study snow in this way before. In order to characterise
mechanical properties, shear testing, compression testing and cohesion testing were
carried out. To investigate snow microstructure, surface profilometry, microscopy and
X-ray microtomography were used.
Correlating the changes observed in snow characteristics with the changes recorded in
the coefficient of friction has allowed the development of an empirical equation. This
can be used to predict the coefficient of friction of a given snow based on three relatively
simple snow measurements: a compression test to calculate the effective modulus, a
roughness measurement to calculate the peak count density and a snow penetration
test.
For the first time this study allows us to use the empirical equation to estimate the
relative contributions of the ploughing and surface friction mechanisms to the total
friction. This allows the comparison of full car-scale test data as it is now possible to
account for variations in the snow test tracks
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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