1,720,988 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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
Effect of Al On Enstatite Solubility In Cmas Clinopyroxenes .2. Crystal-chemical Considerations
No full textThe refinement of the structures of three pyroxenes of composition Di75En10CaTs15, Di65En20CaTs15 and Di70CaTS30 Synthesized in the range T = 1275-1525-degrees-C and P = 14-18 kbar maps out the structural changes occurring in C2/c Di-En-CaTs clinopyroxenes in the CMAS system and completes the existing data along the Di-CaTs join. The most notable features are: 1) the M2 site coordination changes continuously along the Di-En join from 8-fold to 6-fold, with a shift in tetrahedral chains along z. The displacement parameters suggest the coexistence of two structural configurations, clinoenstatite-like and diopside-like; 2) the M2-0 bond lengths become more regular along the Di-CaTs join, as imposed by charge balance requirements. The change in bond lengths is associated with a chain shift along z which is opposite to that observed along the Di-En join. The small values of the displacement parameters suggest an actual change in atomic positions along the join, but with no positional disordering. 3) in Di-En-CaTs ternary clinopyroxenes the opposite chain shifts observed along the two joins compensate. However, displacement parameters are greater than those observed along the join Di-En, suggesting the coexistence of two structural configurations in the average structure. These results suggest that the M2 polyhedron in Al-rich clinopyroxenes is less able to accept extreme Mg at the site than in Al-free clinopyroxenes. This can explain the lower enstatite solubility previously observed in Al-rich clinopyroxenes
Zaoyang Chondrite Cooling History From Fe2+-Mg Intracrystalline Ordering In Pyroxenes
No full textThe crystal chemistry of clinopyroxene, orthopyroxene. and olivine from a crushed fragment of the H5 Zaoyang chondrite has been investigated by X-ray structure refinement and detailed microprobe analysis. The meteoritic pyroxenes have cell and polyhedral volumes which compare well with such data from terrestrial pyroxenes that typically crystallize at low-pressure, Fe2+ and Mg are rather disordered in M1 and M2 sites of clino- and orthopyroxenes; the closure temperatures of the exchange reaction are 600 and 512-degrees-C respectively, which is consistent with a reasonably fast cooling rate, estimated to be of the order of 1-degrees-C/day. The closure temperature for the intercrystalline Ca-Mg exchange reaction for clino- and orthopyroxenes is 900-degrees-C, as calculated from clino- and orthopyroxene intergrowth. The cooling rates obtained from Fe2+-Mg intracrystalline partitioning suggest a cooling of the order of degrees per day at temperatures of 600-500-degrees-C due to a strong loss of heat by irradiation
Ortho-pyroxene From the Serra De Mage Meteorite - Structure Refinement and Estimation of C2/c Pyroxene Contributions To Apparent Pbca Diffraction Violations
No full textTransmission electron microscopy (TEM) of microstructures in the orthopyroxene of the Serra de Mage cumulate eucrite shows augite lamellae thicker than 500 Angstrom, irregularly spaced within the orthopyroxene matrix and parallel to (100), with a(Opx)* = a(Aug)*, [101](Opx)*, = c(Aug)*, and b(Opx)* = b(Aug)*. Streaking along a* owing to stacking disorder was observed in selected-area electron diffraction (SAD) patterns. Slabs of clinopyroxene were observed, but no Guinier-Preston zones were detected. Single-crystal X-ray diffraction (XRD) data were collected and structure refinements completed in space group Pbca, converging to R(obs) = 2.81 and 5.17% for the two samples. Because of the presence of some Okl forbidden reflections with k = 2n + 1 and l = 4n + 2, structure refinement was attempted in space group P2(1)ca, as suggested by previous studies, and in space groups P12(1)/c1 and P112(1)/a, as suggested by the Laue symmetry of the reflections, which is 2/m rather than mmm. However, the high residual indices R and the anomalous values of many displacement parameters and bond distances did not support the lower-symmetry space groups. The violations of the extinction conditions of the Pbca space group and the monoclinic symmetry of the reflections are due to overlap of reflections from the C2/c augite lamellae. From the intensity of the reflections forbidden in Pbca space group, the calculated augite content ranges from approximately 4 to 12%
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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