1,720,965 research outputs found
Modelling the propelled resistance of a freestyle swimmer using computational fluid dynamics
No full textCompetitive swimming has always been a traditional sport, with performance being governed by athlete instinct and feel, the coaches’ experience and time spent in the water. However in recent years the introduction and subsequent banning of the ‘super’ suits has opened the eyes of the sport to what science and engineering can achieve.The focus of improvement is often on generating more propulsive force; however increases in swimming speed can be achieved for the same propulsive power if the resistance is reduced. The resistance acting on a freestyle swimmer is governed by the complex unsteady flow regime, featuring significant body and arm motions, large separated regions and interactions with the free surface. Physically simulating all these aspects within a CFD methodology is computationally very expensive. However it is unclear which unsteady flow features need to be included to accurately represent the active resistance of a freestyle swimmer.The unsteady fluid flow around a freestyle swimmer has be investigated numerically through the use of a combine free surface RANS methodology with the impact of the arms represented using a generic body force model.A detailed analysis of a passive swimmer on the surface has been conducted identifying that free surface interactions have a significant effect on the resistance components of a freestyle swimmer and should be included within future research aimed at reducing resistance.The impact of the arms in the propelled simulations produced a significant variation in total resistance due to free surface interactions, highlighting the importance of the arm entry phase of the stroke. However the arms caused no significant change in the mean resistance and the impact of the arm induced velocities on the resistance is very small. Therefore it is concluded that the effect of the arms are not required in an assessment of mean propelled resistance in freestyle swimming
Forecasting banknotes
Get PDFA central bank’s liquidity forecast is important in ensuring that it supplies the banking system’s need for central bank money. Banknote (or currency in circulation) demand is the largest and for some central banks the most variable component of the liquidity forecast. Accurate forecasting of banknotes is essential in ensuring an accurate liquidity forecast and in turn effective monetary policy implementation. This Handbook discusses these issues and outlines a structural time series state space (STSSS) model which is now used by central banks including the Bank of England and ECB to forecast banknotes (currency in circulation).Forecasting banknotes
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
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