1,721,036 research outputs found
Intrinsic variability of the Antarctic Circumpolar Current System: low- and high-frequency fluctuations of the Argentine Basin flow
No full textIn this paper, the variability of the Antarctic
Circumpolar Current system produced by purely intrinsic
nonlinear oceanic mechanisms is studied through a sigmacoordinate
ocean model, implemented in a large portion of
the Southern Ocean at an eddy-permitting resolution under
steady surface heat and momentum fluxes. The mean transport
through the Drake Passage and the structure of the main
Antarctic Circumpolar Current fronts are well reproduced
by the model. Intrinsic variability is found to be particularly
intense in the Subantarctic Front and in the Argentine
Basin, on which further analysis is focused. The lowfrequency
variability at interannual timescales is related to
bimodal behavior of the Zapiola Anticyclone, with transitions
between a strong and collapsed anticyclonic circulation
in substantial agreement with altimeter observations. Variability
on smaller timescales shows clear evidence of topographic
Rossby-wave propagation along the eastern and
southern flanks of the Zapiola Rise and of mesoscale eddies,
also in agreement with altimeter observations. The analysis
of the relationship between the low- and high-frequency variability
suggests possible mechanisms of mutual interaction
Intrinsic low-frequency variability and predictability of the Kuroshio current and of its extension
No full textInvestigations of the intrinsic low-frequency variability and predictability of the
Kuroshio Current and of its extension jet (the Kuroshio Extension, KE) are reviewed.
The Kuroshio and KE in the North Pacific constitute a western boundary current
system of great relevance from climatological and ecological viewpoints. Both the
Kuroshio south of Japan and the KE display remarkable changes of bimodal character
on interannual time scales that are believed to be intrinsic, i.e., basically generated by
nonlinear oceanic mechanisms rather than by direct atmospheric forcing. Model
studies of the Kuroshio and KE with climatological forcing are thus reviewed.
Moreover, as these changes are chaotic, their predictability requires peculiar
mathematical approaches: theoretical results concerning this important issue are
therefore reviewed as well. Model studies aimed at determining the optimal precursors
and optimally growing initial errors for the Kuroshio are described. Techniques based
on Lyapunov exponents (including their Lagrangian extension) and on data assimilation
techniques (namely, sequential importance sampling using a particle-filtering approach)
are reviewed for the KE. The key problem of how to identify the areas where targeted
observations can improve the forecast is also addressed. The role of wind forcing in
triggering the KE oscillations is finally considered
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
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
- …
