1,721,205 research outputs found
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
Petrographic, geochemical and isotopic constraints on magma dynamics and mixing in the Miocene Monte Capanne monzogranite (Elba Island, Italy)
No full textThe Monte Capanne pluton (Tuscan Magmatic Province, Elba Island, Italy) displays a great variety of magmatic products. Mafic microgranular enclaves (MME) are widespread and display variable size, texture and composition. Petrographic and mineralogical features highlight the importance of magma mixing in their genesis. In particular, patchy-zoned phenocrysts and corroded An-rich plagioclase are common in the MME, which, together with their abundance in the monzogranitic host, suggest that mixing between mantle and crustal-derived magmas occurred relatively early in the crystallisation history of the pluton. A gabbroic enclave is characterised by the abundance of An-rich plagioclase and amphibole, the latter possibly replacing former clinopyroxene. Differences in biotite composition between MME reflect the heterogeneous nature of the mafic magmas prior to the enclave formation. The importance of magma mixing is also evident in K-feldspar megacrysts, which commonly exhibit resorption surfaces followed rimward by a high-Ba zone. Hybrid Orano dykes, which are the latest magmas injected into the Monte Capanne pluton, display specific disequilibrium textures (i.e. sieve-textured plagioclase phenocrysts) and mineral content (i.e. abundance of amphibole) compared to the MME.
The genesis of most MME, which display a wide spectrum of major and trace element compositions compared to the host monzogranite, involves a complex interplay between mixing and crystallisation following the input of mantle-derived magma into a silicic magma chamber. Possible loss of the liquid phase from the evolving basic magma may have produced MME distinctively depleted in LREE and enriched in MgO. Fingerprinting the chemical and isotopic signature of the basic magma involved in the genesis of the MME is further complicated by subsequent (but limited) exchange between MME and host. The basic magma is inferred to be similar to coeval high-K calc-alkaline volcanic rocks occurring on Capraia Island.
Isotopically, the monzogranite and its MME display distinctive trends pointing towards a low-var epsilonNd end-member, represented by a garnet mica schist xenolith. We propose that these trends, together with the abundance of variably digested metasedimentary xenoliths dispersed throughout the pluton, reflect assimilation of metapelitic crust early in the evolution of the pluton during storage of the magma within the Tuscan basement, i.e. prior to the final emplacement of the pluton at upper crustal levels.
The hybrid Orano dykes, which were injected at the end of the Monte Capanne crystallisation history, display distinctive trace element compositions, similar to REE-Sr-Ba-rich andesites on Capraia. The Orano dykes originated from a deeper level of magma storage and interacted with a crystal-rich enclave-bearing monzogranitic mixture.
The proposed scenario involving periodic recharge by mantle-derived magmas and crustal assimilation is also in agreement with isotopic variations observed within a zoned K-feldspar megacryst, which exhibits a core with high 87Sr/86Sr and a rimward decrease of 87Sr/86Sr, arguing for a high 87Sr/86Sr silicic system replenished by lower 87Sr/86Sr mantle-derived magmas
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
Predicting Visible Differences in High Dynamic Range Images - Model and its Calibration
No full textNew imaging and rendering systems commonly use physically accurate lighting information in the form of high-dynamic range (HDR) images and video. HDR images contain actual colorimetric or physical values, which can span 14 orders of magnitude, instead of 8-bit renderings, found in standard images. The additional precision and quality retained in HDR visual data is necessary to display images on advanced HDR display devices, capable of showing contrast of 50,000:1, as compared to the contrast of 700:1 for LCD displays. With the development of high-dynamic range visual techniques comes a need for an automatic visual quality assessment of the resulting images. In this paper we propose several modifications to the Visual Difference Predicator (VDP). The modifications improve the prediction of perceivable differences in the full visible range of luminance and under the adaptation conditions corresponding to real scene observation. The proposed metric takes into account the aspects of high contrast vision, like scattering of the light in the optics (OTF), nonlinear response to light for the full range of luminance, and local adaptation. To calibrate our HDR~VDP we perform experiments using an advanced HDR display, capable of displaying the range of luminance that is close to that found in real scenes
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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