1,720,978 research outputs found
On the combined use of satellite multispectral and radar polarimetric measurements to infer cloud microphysics
No full textThe extensive availability of multispectral satellite observations and polarimetric ground radar measurements enhances the remote sensing capabilities in studying structure and dynamics of cloud systems at all relevant scales. We present here a combined approach to perform a detailed cloud vertical structure analysis, by means of MODIS VIS-NIR products and C-band polarimetric radar data. Satellite products include estimates of cloud optical thickness, cloud particles effective radius and cloud top phase, to be matched with the polarimetric hydrometeor 3D classification as obtained by a fuzzy logic algorithm. The problem of matching of the two datasets is discussed and the procedure is applied to three case studies that occurred in Northern Italy. Results are presented in terms of vertical hydrometeor profile and satellite derived microphysical cloud properties, showing the capability of the combined approach in the 3D rendering of cloud structures, with envisaged applications for precipitation studies and data assimilation in meteorological models
Spatial characterization of raincell horizontal profiles from C-band radar measurements at mid-latitude
No full textMicrophysical Evolution of a Convective Event retrieved from Two Operational Polarimetric C-Band Radars
No full textThe analysis of the evolution of convective clouds and their
correspondent microphysics vertical distribution will
contribute to a better understanding of convective processes
and will improve the representation of cloud evolution and
latent heat formation for assimilation in NWP models.
The use of polarimetric radar measurements allows us to
identify the prevailing hydrometeor type and their spatial
distribution within a meteorological event.
The study is carried out using two polarimetric Cband
radars located 90 km apart in the Po Valley of Northern
Italy, the S. Pietro Capofiume and the Gattatico radars, both
managed by ARPA EmiliaRomagna.
The radar observations are collected during the transition of
a severe evolving storm occurred on the afternoon of 20 may
2003, moving across the region explored by the two radars,
and the microphysical properties are obtained by using an
hydrometeor classification scheme developed at the National
Severe Storms Laboratory, and recently extended from Sband
to Cband radar data.
The aim of the work is the reconstruction of the 3D
storm structure vertical evolution to understand how the
microphysical properties change during the different stages
of the storm formation and development (from the early to
the mature and then dissipative stage of the cloud system).
Further “storm representative” vertical hydrometeor profiles
will be discussed in order to elucidate the microphysical
processes occurring during the storm’s lifetime and their
consequence on the ground rainfall field estimation.
A next step of this kind of analysis will be the comparison
with NWP simulated profiles, to check if they are able to
reproduce the reference hydrometeor vertical profiles seen
by the radars
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
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