1,721,036 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
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
Imaging and Understanding Atomic-Scale Adhesion and Wear: Quantitative investigations Using in situ TEM
Full text linkThe underlying physics governing tribological interactions - adhesion, friction, lubrication, and wear - are poorly understood. Significant progress has been enabled by nanoscale studies using the atomic force microscope (AFM). However, AFM lacks direct access to the contact geometry and structure. In this thesis, nanoscale adhesion and wear tests were performed inside of a transmission electron microscope (TEM), enabling real-time in situ interrogation of the contact in vacuum. Quantitative data was extracted using custom analysis routines to resolve tip shape, volume changes, and adhesive forces with unprecedented resolution.
From in situ adhesion tests, a novel method was developed to extract the work of adhesion (0.66±0.14 J/m^2) and range of adhesion (0.25±0.06 nm) between silicon and diamond. The latter quantity has not previously been measured experimentally. TEM adhesion tests and complementary atomistic simulations reveal an order-of-magnitude reduction in apparent work of adhesion as tip roughness increased from atomic-scale to a root-mean-square value of 1 nm. Using an existing analytical model, an empirically derived roughness-independent adhesion parameter was extracted. In situ wear tests of silicon on diamond at low load revealed the mechanism of wear to be consistent with atom-by-atom processes. The rate of atomic removal varied exponentially with average normal stress, consistent with stress-mediated chemical reaction kinetics. This yields a physically reasonable activation energy (0.85±0.06 eV), and activation volume (6.7±0.3 �). This framework can be generalized to understand and potentially predict wear in many materials undergoing atom-by-atom removal.
Together, these investigations advance the scientific understanding of nanoscale adhesion and wear and help bridge the gap between experiments and atomistic simulations. Three examples are demonstrated where nanometer-scale trends can be predicted using continuum approaches: nanoscale adhesive forces can be calculated using an interaction potential; apparent work of adhesion depends on nanoscale root-mean-square roughness; and the rate of atomic-scale wear reactions is determined by the average normal contact stress. These examples, while only demonstrated in the specific systems studied, suggest strategies and future research directions for understanding, predicting, and controlling tribological phenomena
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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
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