1,720,995 research outputs found
Spatter and welded air fall deposits generated by fire-fountaining eruptions: Cooling of pyroclasts during transport and deposition
No full textAccording to the physico-mathematical model presented here, juvenile ballistic fragments can travel through the
atmosphere during fire-fountaining eruptions preserving enough heat to agglutinate or to weld on impact with the ground’s
surface, even a few kilometres from the source area. The range is mostly related to exit velocity and ejection angle as well as
to such typical properties of the transported particles as size, density and shape. The selective nature of the transport system
can give rise to inverse lateral size/density grading. The most important interdependent factors that control the degree of final
agglutination or welding are accumulation rate, grain size and duration of deposition. In the investigated grain size range, an
accumulation rate of 0.2 m/h appears as a minimum value to promote welding. This value cannot be considered as an
absolute threshold because it can be significantly lowered by increasing the grain size. Duration of deposition appears as
another critical factor because it controls the maximum temperature of the whole deposit and its final thickness, and
therefore, the cooling rate of its main portion after the end of deposition. In the case of high accumulation rates of coarse
particles but during a short period of time, primary agglutination may be the dominant factor in controlling the final sintering
of particles. Conversely, high accumulation rates of coarse particles during a long period of time give rise to both primary
agglutination and welding
Tropospheric water vapor from LEO-LEO occultation: estimation by differential attenuation measurements near 20GHz
No full text
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
A Coordinate Registration Technique for OTH Sky-wave Radars Based on 3D Ray-tracing and Sea-land Transitions
No full textDispelling 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
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