1,720,963 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
Étude de la robustesse de transistors GaN en régime de court-circuit
No full textThis thesis aims to evaluate the short-circuit robustness of commercial GaN 600 V normally-off transistors. A review of the literature describes the different structures of GaN transistors, their possible applications, and study the short-circuit tests carried out from 2013 to 2021. The robustness of the transistors is evaluated by measuring the Time Leading to failure (TLF). For 600/650 V transistors, when the DC bus voltage is set to 400 V, the TLF is less than 10 µs. For lower DC bus voltages (below 300/350 V), rapid failures are also recorded (TLF100 µs).Three short-circuit benches were manufactured, with low parasitic inductance to avoid self-sustaining oscillations.Four HEMT structures were tested: two P-GaN HEMTs (from GaN Systems and Panasonic manufacturers), a cascode component (from the Transphorm manufacturer) and a MIS-HEMT, prototype of the CEA-LETI. Between 2016 and 2019, more than 200 destructive short-circuit tests were carried out. The robustness is on average low, and very dispersed. The bus voltage strongly impacts the TLF. The robustness has improved batch after batch for the P-GaN gate HEMTs of GaN Systems. On the other hand, the cascode transistor (Transphorm) and the HEMT GIT (Panasonic) are fragile when the DC bus voltage is set to 400 V.Finally, around fifteen P-GaN gate HEMTs were characterized before subjecting them to a destructive short-circuit test, and no correlation was found between the TLF observed and any of the parameters measured during these characterizations.Cette thèse vise à évaluer la robustesse en court-circuit de transistors GaN 600 V normally-off du commerce. Une revue de la littérature décrit les différentes structures des transistors GaN, leurs applications possibles, et balaie les essais de court-circuit réalisés de 2013 à 2021. La robustesse des transistors est évaluée par la mesure de la durée avant défaillance (Time Leading to Failure ou TLF). Pour les transistors 600/650 V, lorsque la tension du bus continu est réglée à 400 V, il en ressort une faible robustesse (TLF100 µs).Trois bancs de court-circuit ont été réalisés, en cherchant à minimiser leur inductance parasite pour éviter des oscillations auto-entretenues.Quatre structures de HEMTs ont été testées : deux HEMTs P-GaN (des fondeurs GaN Systems et Panasonic) ; un composant cascode (du fondeur Transphorm) ; enfin, un MIS-HEMT, prototype du CEA-LETI. Entre 2016 et 2019, plus de 200 essais de courts-circuits destructifs ont été réalisés. La robustesse est en moyenne faible, et très dispersée. La tension de bus impacte fortement le TLF. La robustesse s’est améliorée au fil des lots testés pour le HEMT P-GaN du fabricant GaN Systems. En revanche, le transistor cascode (Transphorm) et le HEMT GIT (Panasonic) restent fragiles sous 400 V. Enfin, une quinzaine de HEMTs à grille P-GaN ont été caractérisés en statique avant de les soumettre à un essai de court-circuit destructif, et aucune corrélation n’a été trouvée entre la durée avant défaillance constatée et l’un des paramètres mesurés lors de ces caractérisations
Étude de la robustesse de transistors GaN en régime de court-circuit
No full textThis thesis aims to evaluate the short-circuit robustness of commercial GaN 600 V normally-off transistors. A review of the literature describes the different structures of GaN transistors, their possible applications, and study the short-circuit tests carried out from 2013 to 2021. The robustness of the transistors is evaluated by measuring the Time Leading to failure (TLF). For 600/650 V transistors, when the DC bus voltage is set to 400 V, the TLF is less than 10 µs. For lower DC bus voltages (below 300/350 V), rapid failures are also recorded (TLF100 µs).Three short-circuit benches were manufactured, with low parasitic inductance to avoid self-sustaining oscillations.Four HEMT structures were tested: two P-GaN HEMTs (from GaN Systems and Panasonic manufacturers), a cascode component (from the Transphorm manufacturer) and a MIS-HEMT, prototype of the CEA-LETI. Between 2016 and 2019, more than 200 destructive short-circuit tests were carried out. The robustness is on average low, and very dispersed. The bus voltage strongly impacts the TLF. The robustness has improved batch after batch for the P-GaN gate HEMTs of GaN Systems. On the other hand, the cascode transistor (Transphorm) and the HEMT GIT (Panasonic) are fragile when the DC bus voltage is set to 400 V.Finally, around fifteen P-GaN gate HEMTs were characterized before subjecting them to a destructive short-circuit test, and no correlation was found between the TLF observed and any of the parameters measured during these characterizations.Cette thèse vise à évaluer la robustesse en court-circuit de transistors GaN 600 V normally-off du commerce. Une revue de la littérature décrit les différentes structures des transistors GaN, leurs applications possibles, et balaie les essais de court-circuit réalisés de 2013 à 2021. La robustesse des transistors est évaluée par la mesure de la durée avant défaillance (Time Leading to Failure ou TLF). Pour les transistors 600/650 V, lorsque la tension du bus continu est réglée à 400 V, il en ressort une faible robustesse (TLF100 µs).Trois bancs de court-circuit ont été réalisés, en cherchant à minimiser leur inductance parasite pour éviter des oscillations auto-entretenues.Quatre structures de HEMTs ont été testées : deux HEMTs P-GaN (des fondeurs GaN Systems et Panasonic) ; un composant cascode (du fondeur Transphorm) ; enfin, un MIS-HEMT, prototype du CEA-LETI. Entre 2016 et 2019, plus de 200 essais de courts-circuits destructifs ont été réalisés. La robustesse est en moyenne faible, et très dispersée. La tension de bus impacte fortement le TLF. La robustesse s’est améliorée au fil des lots testés pour le HEMT P-GaN du fabricant GaN Systems. En revanche, le transistor cascode (Transphorm) et le HEMT GIT (Panasonic) restent fragiles sous 400 V. Enfin, une quinzaine de HEMTs à grille P-GaN ont été caractérisés en statique avant de les soumettre à un essai de court-circuit destructif, et aucune corrélation n’a été trouvée entre la durée avant défaillance constatée et l’un des paramètres mesurés lors de ces caractérisations
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
Robustness study on GaN transistors for short-circuit operation
No full textCette thèse vise à évaluer la robustesse en court-circuit de transistors GaN 600 V normally-off du commerce. Une revue de la littérature décrit les différentes structures des transistors GaN, leurs applications possibles, et balaie les essais de court-circuit réalisés de 2013 à 2021. La robustesse des transistors est évaluée par la mesure de la durée avant défaillance (Time Leading to Failure ou TLF). Pour les transistors 600/650 V, lorsque la tension du bus continu est réglée à 400 V, il en ressort une faible robustesse (TLF100 µs).Trois bancs de court-circuit ont été réalisés, en cherchant à minimiser leur inductance parasite pour éviter des oscillations auto-entretenues.Quatre structures de HEMTs ont été testées : deux HEMTs P-GaN (des fondeurs GaN Systems et Panasonic) ; un composant cascode (du fondeur Transphorm) ; enfin, un MIS-HEMT, prototype du CEA-LETI. Entre 2016 et 2019, plus de 200 essais de courts-circuits destructifs ont été réalisés. La robustesse est en moyenne faible, et très dispersée. La tension de bus impacte fortement le TLF. La robustesse s’est améliorée au fil des lots testés pour le HEMT P-GaN du fabricant GaN Systems. En revanche, le transistor cascode (Transphorm) et le HEMT GIT (Panasonic) restent fragiles sous 400 V. Enfin, une quinzaine de HEMTs à grille P-GaN ont été caractérisés en statique avant de les soumettre à un essai de court-circuit destructif, et aucune corrélation n’a été trouvée entre la durée avant défaillance constatée et l’un des paramètres mesurés lors de ces caractérisations.This thesis aims to evaluate the short-circuit robustness of commercial GaN 600 V normally-off transistors. A review of the literature describes the different structures of GaN transistors, their possible applications, and study the short-circuit tests carried out from 2013 to 2021. The robustness of the transistors is evaluated by measuring the Time Leading to failure (TLF). For 600/650 V transistors, when the DC bus voltage is set to 400 V, the TLF is less than 10 µs. For lower DC bus voltages (below 300/350 V), rapid failures are also recorded (TLF100 µs).Three short-circuit benches were manufactured, with low parasitic inductance to avoid self-sustaining oscillations.Four HEMT structures were tested: two P-GaN HEMTs (from GaN Systems and Panasonic manufacturers), a cascode component (from the Transphorm manufacturer) and a MIS-HEMT, prototype of the CEA-LETI. Between 2016 and 2019, more than 200 destructive short-circuit tests were carried out. The robustness is on average low, and very dispersed. The bus voltage strongly impacts the TLF. The robustness has improved batch after batch for the P-GaN gate HEMTs of GaN Systems. On the other hand, the cascode transistor (Transphorm) and the HEMT GIT (Panasonic) are fragile when the DC bus voltage is set to 400 V.Finally, around fifteen P-GaN gate HEMTs were characterized before subjecting them to a destructive short-circuit test, and no correlation was found between the TLF observed and any of the parameters measured during these characterizations
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