1,720,956 research outputs found
Open-ocean convection in the Greenland Sea: Preconditioning through a mesoscale chimney and detectability in SAR imagery studied with a hierarchy of nested numerical models
No full textAspects of the hydrodynamics of the Greenland Sea were investigated through a hierarchy of nested numerical models. The simulations were particularly conceived to study, under realistic conditions, the hydrodynamics induced by the presence of a convectively generated oceanic mesoscale chimney as well as its "long-term" influence on the local convective activity. To this purpose, a very high resolution, fully non-hydrostatic 3D model capable of simulating submesoscale convective vertical plumes was nested into an ocean-ice, regional hydrostatic 3D model which was initialised and forced through the global, coupled atmosphere ocean 3D REMO/MPI-OM model. In the central part of the Greenland Sea, the hydrological structure of an observed, convectively generated oceanic mesoscale chimney and a corresponding reconstructed velocity field were imposed as a part of the forcing for the non-hydrostatic numerical model. Two different, "short-term" realistic scenarios were simulated corresponding, respectively, to episodes characterized by a strong mean oceanic heat loss and by a weak mean oceanic heat gain in the central Greenland Sea. In order to evaluate the role played by mesoscale convective chimneys in promoting preconditioning to open-ocean deep-penetrating convection, two "long-term" simulations of the hydrodynamics of the Greenland Sea were performed using the same model hierarchy and the forcing as described above. The two runs differed merely in that only in one of them the hydrological and velocity structure of a convective chimney were inserted in the central Greenland Sea as a part of the forcing. The dependence of simulated surface convergence patterns on grid step in the central Greenland Sea was also investigated in order to assess the capability of numerical models of predicting the detectability of convective events in synthetic aperture radar imagery
Interpretation of convection cell signatures in radar images of the Greenland Sea
No full textWe present a comprehensive analysis of a convection cell pattern in two SAR images of a site in the Greenland Sea from the satellites ERS-2 and RADARSAT. It is not obvious whether the observed radar signatures can be attributed to oceanic or atmospheric convection phenomena. We show by numerical simulations that they are, on the on hand, not consistent with the theory of oceanic convection features and their radar imaging mechanism, while, on the other hand, they could very well be caused by atmospheric convection cells. The conclusion that the observed features must be atmospheric convection cells is supported by in-situ data and an AVHRR image of the scenario. We discuss the significance of our findings in view of the general problem of discriminating between radar signatures of oceanic and atmospheric phenomena
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
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