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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
Dynamique multi-échelle de l'eau dans la boehmite : une approche par RMN
No full textDans plusieurs domaines de la chimie, les catalyseurs occupent une place importante puisqu’ils assurent une réaction plus rapide, une meilleure sélectivité et réduisent l’utilisation de matières premières. L’industrie s’est récemment tournée vers les catalyseurs hétérogènes dont la récupération est plus facile. Ces catalyseurs sont constitués d’un support poreux et de sites actifs répartis en surface à travers la porosité du support. Pour optimiser pleinement le support, de récentes études ont abordé la question de l’accessibilité des molécules aux sites réactionnels. Cela passe notamment par la compréhension de la mobilité des solvants et du trafic moléculaire dans le milieu poreux. Le support catalytique hétérogène par excellence est l’alumine γ, obtenue par calcination topotactique de la boehmite. La texture et les propriétés poreuses sont principalement héritées de la boehmite, en particulier de l’organisation des agglomérats et des agrégats. Cette organisation est principalement obtenue lors des étapes de mise en forme (peptisation) et d’extrusion lors du procédé d’obtention de l’alumine. Le transport et la dynamique multi-échelle à l’intérieur de la boehmite seront étudiés au cours de ces deux étapes, notamment comment les molécules de solvant (ici l’eau) se déplacent à l’intérieur de ce matériau et quels mécanismes pilotent la dynamique. Afin d’étudier cette dynamique, des suspensions de boehmite avec différentes textures initiales seront obtenues par dialyse et stress osmotique et les extrudés par une voie industrielle usuelle. Le transport autour de l’interface des agrégats et des parois des pores (échelle nanométrique) sera étudié par Résonance Magnétique Nucléaire à champ cyclé sur une échelle de temps de la nanoseconde à la microseconde. La diffusion a été suivie à la surface de ces objets et s’est avérée être régie par une forte interaction avec la surface, en particulier la courbure de surface. Il a notamment été trouvé un temps de séjour important (≈ 8μs) des molécules d’eau à la surface et un coefficient de diffusion de surface lent (< 3. 10-10 m2/s). À l’échelle du micron, la dynamique est étudiée par RMN à gradient de champ pulsé sur une échelle de temps de la milliseconde à la seconde. La diffusion semble être gouvernée par la structure topologique résultant de l’organisation complexe des agrégats et des agglomérats (connectivité des pores, anisotropie, etc.).For several domains of chemistry, catalyst take up a significant place since they ensure a quicker reaction, a better selectivity and reduce the use of raw material. Industry has recently turned to heterogeneous catalyst whose recovery is easier. These catalysts consist of a porous support and active sites distributed on the surface through the support porosity. To fully optimized the support, recent studies have tackled the issue of accessibility of molecules to the reaction sites. This one includes the comprehension of solvent mobility and molecular traffic in the porous medium. The heterogeneous catalytic support par excellence is γ-alumina, obtained by a topotactic calcination of boehmite. Texture and porous properties are then mostly inherited from boehmite, especially from the organization of agglomerates and aggregates. This organization is mostly obtained during the kneading, (peptization) and the extrusion steps of the boehmite-to-alumina process. Transport and multi-scale dynamics inside boehmite will then be investigated during these two steps particularly how solvent molecules (here water) move inside this material and what mechanisms drive the dynamics . To study this dynamics, boehmite suspensions with different initial textures will be obtained through dialysis and osmotic stress and extrudates from the traditional industrial route. Transport around the interface of aggregates and pore walls (nanometric scale) will be studied by Field Cycling Nuclear Magnetic Resonance on a ns-µs time scale. Diffusion was followed at the surface of such objects and was found to be governed by a strong interaction with the surface and especially the surface curvature. A consequent residence time (≈ 8µs) of water molecules at the surface and a rather slow surface diffusion coefficient (< 3. 10-10 m2/s) was exhibited. At the micron scale, dynamics is investigated by Pulsed Field Gradient NMR on a millisecond to second time scale. Diffusion seems to be driven by the topological structure imposed by the complex organization of aggregates and agglomerates (connected pore, anisotropy, etc.)
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
Dynamique multi-échelle de l'eau dans la boehmite : une approche par RMN
No full textFor several domains of chemistry, catalyst take up a significant place since they ensure a quicker reaction, a better selectivity and reduce the use of raw material. Industry has recently turned to heterogeneous catalyst whose recovery is easier. These catalysts consist of a porous support and active sites distributed on the surface through the support porosity. To fully optimized the support, recent studies have tackled the issue of accessibility of molecules to the reaction sites. This one includes the comprehension of solvent mobility and molecular traffic in the porous medium. The heterogeneous catalytic support par excellence is γ-alumina, obtained by a topotactic calcination of boehmite. Texture and porous properties are then mostly inherited from boehmite, especially from the organization of agglomerates and aggregates. This organization is mostly obtained during the kneading, (peptization) and the extrusion steps of the boehmite-to-alumina process. Transport and multi-scale dynamics inside boehmite will then be investigated during these two steps particularly how solvent molecules (here water) move inside this material and what mechanisms drive the dynamics . To study this dynamics, boehmite suspensions with different initial textures will be obtained through dialysis and osmotic stress and extrudates from the traditional industrial route. Transport around the interface of aggregates and pore walls (nanometric scale) will be studied by Field Cycling Nuclear Magnetic Resonance on a ns-µs time scale. Diffusion was followed at the surface of such objects and was found to be governed by a strong interaction with the surface and especially the surface curvature. A consequent residence time (≈ 8µs) of water molecules at the surface and a rather slow surface diffusion coefficient (< 3. 10-10 m2/s) was exhibited. At the micron scale, dynamics is investigated by Pulsed Field Gradient NMR on a millisecond to second time scale. Diffusion seems to be driven by the topological structure imposed by the complex organization of aggregates and agglomerates (connected pore, anisotropy, etc.).Dans plusieurs domaines de la chimie, les catalyseurs occupent une place importante puisqu’ils assurent une réaction plus rapide, une meilleure sélectivité et réduisent l’utilisation de matières premières. L’industrie s’est récemment tournée vers les catalyseurs hétérogènes dont la récupération est plus facile. Ces catalyseurs sont constitués d’un support poreux et de sites actifs répartis en surface à travers la porosité du support. Pour optimiser pleinement le support, de récentes études ont abordé la question de l’accessibilité des molécules aux sites réactionnels. Cela passe notamment par la compréhension de la mobilité des solvants et du trafic moléculaire dans le milieu poreux. Le support catalytique hétérogène par excellence est l’alumine γ, obtenue par calcination topotactique de la boehmite. La texture et les propriétés poreuses sont principalement héritées de la boehmite, en particulier de l’organisation des agglomérats et des agrégats. Cette organisation est principalement obtenue lors des étapes de mise en forme (peptisation) et d’extrusion lors du procédé d’obtention de l’alumine. Le transport et la dynamique multi-échelle à l’intérieur de la boehmite seront étudiés au cours de ces deux étapes, notamment comment les molécules de solvant (ici l’eau) se déplacent à l’intérieur de ce matériau et quels mécanismes pilotent la dynamique. Afin d’étudier cette dynamique, des suspensions de boehmite avec différentes textures initiales seront obtenues par dialyse et stress osmotique et les extrudés par une voie industrielle usuelle. Le transport autour de l’interface des agrégats et des parois des pores (échelle nanométrique) sera étudié par Résonance Magnétique Nucléaire à champ cyclé sur une échelle de temps de la nanoseconde à la microseconde. La diffusion a été suivie à la surface de ces objets et s’est avérée être régie par une forte interaction avec la surface, en particulier la courbure de surface. Il a notamment été trouvé un temps de séjour important (≈ 8μs) des molécules d’eau à la surface et un coefficient de diffusion de surface lent (< 3. 10-10 m2/s). À l’échelle du micron, la dynamique est étudiée par RMN à gradient de champ pulsé sur une échelle de temps de la milliseconde à la seconde. La diffusion semble être gouvernée par la structure topologique résultant de l’organisation complexe des agrégats et des agglomérats (connectivité des pores, anisotropie, etc.)
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
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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