1,720,978 research outputs found

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

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    “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

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    We 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

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    We 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

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We 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

    Development of a time-space chirp technique with SAW-IDT sensors : application to the characterization of thin layers, coatings and functional surfaces

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    Ce travail rentre dans le cadre de la caractérisation des couches minces, de revêtements et de surfaces fonctionnelles (épaisseur, constantes élastiques,…). Parmi les méthodes de caractérisation potentielles, les méthodes ultrasonores employant des ondes de surface sont particulièrement intéressantes. Pour ce faire, nous avons choisi d’exploiter la dispersion des ondes de surface de type Rayleigh. En effet, les ondes acoustiques de surface (SAW) de type Rayleigh se propagent à la surface d’un matériau et l’énergie véhiculée par ces ondes est confinée sous la surface dans une couche d’épaisseur de l’ordre d’une longueur d’onde. Afin de caractériser ces revêtements, il est nécessaire de travailler sur une large gamme de fréquences. D’autre part, ces couches peuvent être fragiles et transparentes, c’est pourquoi, des transducteurs interdigités (IDT) sont envisagés. Pour optimiser ce type de capteurs, et en particulier leur bande passante, il est nécessaire d’étudier différentes configurations sachant qu’il est notamment possible de faire varier le nombre d’électrodes, les dimensions des électrodes, leurs formes et leurs espacements. Enfin, pour exciter ces ondes de surface dans une large gamme de fréquence avec des niveaux de déplacement suffisants pour la caractérisation des couches minces et revêtements, la technique à double Chirp spatio-temporel basée sur des transducteurs SAW-IDT a été privilégiée. Nous avons montré les potentialités de cette approche en caractérisant premièrement des structures à couche mince métalliques d’épaisseurs de 100 nm et plus, et deuxièmement des revêtements transparents de type sol-gel.This work is within the scope of characterization of thin layers, coatings and functional surfaces (thickness, elastic constants,…). Among the characterization methods, the ultrasonic methods using surface acoustic waves are particularly interesting. In order to do this, we chose to make use the dispersion phenomenon of Rayleigh-like surface acoustic waves. Indeed, the propagation of these waves is close to the surface of material and the energy is concentrated within a layer under the surface of about one wavelength thick. In order to characterize these coatings and structures, it is necessary to perform measurements in high frequencies. On the other hand, these coatings can be fragile and transparent, this is why in this study, SAW-IDT sensors are achieved for surface acoustic wave generation. For optimization of these SAW-IDT sensors, particularly their band-width, it is necessary to study various IDT configurations by varying the number of electrodes, dimensions of the electrodes, their shapes and spacings. Finally, to generate the surface acoustic waves over a wide frequency range with sufficient displacement amplitude for the characterization of thin films and coatings, a time-space chirp technique with SAW-IDT sensors was selected. We have shown the potential of this approach by characterizing firstly thin metallic layers, and secondly transparent coatings obtained by the sol-gel process

    Développement d'une technique à double Chirp spatio-temporel basée sur des capteurs SAW-IDT : application à la caractérisation de couches minces et de revêtements fonctionnels

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    This work is within the scope of characterization of thin layers, coatings and functional surfaces (thickness, elastic constants,…). Among the characterization methods, the ultrasonic methods using surface acoustic waves are particularly interesting. In order to do this, we chose to make use the dispersion phenomenon of Rayleigh-like surface acoustic waves. Indeed, the propagation of these waves is close to the surface of material and the energy is concentrated within a layer under the surface of about one wavelength thick. In order to characterize these coatings and structures, it is necessary to perform measurements in high frequencies. On the other hand, these coatings can be fragile and transparent, this is why in this study, SAW-IDT sensors are achieved for surface acoustic wave generation. For optimization of these SAW-IDT sensors, particularly their band-width, it is necessary to study various IDT configurations by varying the number of electrodes, dimensions of the electrodes, their shapes and spacings. Finally, to generate the surface acoustic waves over a wide frequency range with sufficient displacement amplitude for the characterization of thin films and coatings, a time-space chirp technique with SAW-IDT sensors was selected. We have shown the potential of this approach by characterizing firstly thin metallic layers, and secondly transparent coatings obtained by the sol-gel process.Ce travail rentre dans le cadre de la caractérisation des couches minces, de revêtements et de surfaces fonctionnelles (épaisseur, constantes élastiques,…). Parmi les méthodes de caractérisation potentielles, les méthodes ultrasonores employant des ondes de surface sont particulièrement intéressantes. Pour ce faire, nous avons choisi d’exploiter la dispersion des ondes de surface de type Rayleigh. En effet, les ondes acoustiques de surface (SAW) de type Rayleigh se propagent à la surface d’un matériau et l’énergie véhiculée par ces ondes est confinée sous la surface dans une couche d’épaisseur de l’ordre d’une longueur d’onde. Afin de caractériser ces revêtements, il est nécessaire de travailler sur une large gamme de fréquences. D’autre part, ces couches peuvent être fragiles et transparentes, c’est pourquoi, des transducteurs interdigités (IDT) sont envisagés. Pour optimiser ce type de capteurs, et en particulier leur bande passante, il est nécessaire d’étudier différentes configurations sachant qu’il est notamment possible de faire varier le nombre d’électrodes, les dimensions des électrodes, leurs formes et leurs espacements. Enfin, pour exciter ces ondes de surface dans une large gamme de fréquence avec des niveaux de déplacement suffisants pour la caractérisation des couches minces et revêtements, la technique à double Chirp spatio-temporel basée sur des transducteurs SAW-IDT a été privilégiée. Nous avons montré les potentialités de cette approche en caractérisant premièrement des structures à couche mince métalliques d’épaisseurs de 100 nm et plus, et deuxièmement des revêtements transparents de type sol-gel
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