1,721,109 research outputs found
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
Optimal cycling time trial position models
No full textIntroduction: The aerodynamic drag of a cyclist in time trial (TT) position is strongly influenced by the torso angle (Underwood et al. 2011). To minimize drag, cyclists lower their torso angle. Along with the drag the cyclists’ peak power output decreases. There should be a trade-off between the loss in power output and drag as function of cycling velocity. This hypothesis is supported by the energy expenditure which is a function of the workload divided by the gross efficiency (GE). The workload to overcome drag decreases with smaller torso angles, while the GE decreases accordingly. Previous literature suggested that the aerodynamic losses outweigh the loss in power output (Lukes et al. 2005). However, these statements are only valid for elite TT cycling velocities, e.g. > 45 km/h. To our best knowledge, there is no published prediction at which speed the aerodynamic power loss starts to dominate. Therefore the aim of this study is to predict the optimal TT cycling position as a function of velocity to improve the performance of non-elite cyclists.
Methods: Two models were developed to determine the optimal torso angle of TT cyclists: a ‘Power Output Model’ and a ‘Metabolic Efficiency Model’. The Power Output Model predicts the optimal cycling position by maximizing the peak power output minus the power losses due to drag and roll resistance. The Metabolic Efficiency Model minimizes the required cycling energy. Model input parameters were experimentally collected of 19 trained competitive time trial cyclists (Fintelman et al. 2012). The main input variables were the power output, frontal area and GE of the cyclists in different torso angle positions (0,8,16 and 24°). The optimal cycling torso angle was predicted for speeds between 18-50km/h.
Results and discussion: For both models, the optimal torso angle is dependent on the cycling velocity, and the torso angle exhibited a sigmoid-like shape, with decreasing torso angles at increasing velocities. The Power Output Model curve was shifted to a higher velocity, which could be explained by the different approach of the models. The aerodynamic losses outweighed the power losses for velocities above 45km/h, which goes in line with the literature. For cycling velocities below 30km/h the power loss and gross efficiency due to position change were dominant. Furthermore, it is shown that a fully horizontal torso is not optimal.
Conclusion and recommendations: It is suggested that despite some limitations, the models give valuable information about the optimal TT cycling position at different speeds for non-elite cyclists. This study showed it is beneficial to ride in a more upright TT position when velocities are below 30km/h, while at speeds above 45km/h an almost flat back is optimal. Furthermore, for speeds between 32-40km/h in an endurance event it is advisable to lower the torso despite the fact that the power output in a more aerodynamic position is decreased. In contrast, in sprinting or in variable conditions (wind, undulating course, etc) at these speeds it is more beneficial to ride in a more upright TT position.
Our future research will attempt to measure the aerodynamic drag of all participants in a wind tunnel, to implement a more valid drag coefficient and thus improving the validity of the models. Furthermore, to increase the ecological validity the effect of crosswind will be implemented in future.
References:
Fintelman, Highton, Adams, Sterling, Hemida, Li (2012) ECSS annual conference.
Lukes R, Chin S, Haake S (2005). Sports Eng., 8(2): 59-74.
Underwood L, Schumacher J, Burette-Pommay J, Jermy M (2011). Sports Eng., 14(2): 147-154
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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