1,720,986 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
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
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
Study and optimization of a joint source-channel video-transmission system based on "SoftCast"
No full textDes nouveaux schémas de Codage Vidéo Linéaire (CVL) ont démontré ces dernières années un potentiel élevé pour la diffusion de contenus vidéo sur des canaux de transmission sans-fil sévères. SoftCast représente le pionnier des schémas CVL. Différent des standards de transmission vidéo actuels et particulièrement utile en situation de broadcast, SoftCast est un système de codage conjoint source-canal où les pixels sont traités par des opérations linéaires successives (transformée DCT, allocation de puissance, modulation quasi-analogique) et directement transmis sans quantification ni codage (entropique ou de canal). SoftCast permet ainsi d’offrir une qualité vidéo reçue directement proportionnelle à la qualité du canal de transmission, sans aucune information de retour et tout en évitant les mécanismes d’adaptation complexes des schémas classiques. Un premier objectif de ces travaux de thèse concerne l’étude des performances de bout en bout de SoftCast. Des modèles théoriques sont ainsi proposés prenant en compte les contraintes de bande passante de l’application, l’allocation de puissance, ainsi que le type de décodeur utilisé à la réception (LLSE, ZF). Une deuxième partie basée sur une campagne de tests subjectifs concerne une étude originale de la qualité vidéo et des artefacts spécifiques associés à SoftCast. Dans une troisième partie, des méthodes de prétraitement permettant d’accroître la qualité reçue sont proposées avec un gain moyen en PSNR de l’ordre de 3 dB. Finalement, un algorithme adaptatif modifiant la taille du groupe d’images (GoP) en fonction des caractéristiques du contenu vidéo transmis est proposé. Cette solution permet d’obtenir des gains supplémentaires en PSNR de l’ordre de 1 dB.Linear video coding (LVC) schemes have recently demonstrated a high potential for delivering video content over challenging wireless channels. SoftCast represents the pioneer of the LVC schemes. Different from current video transmission standards and particularly useful in broadcast situation, SoftCast is a joint source-channel coding system where pixels are processed by successive linear operations (DCT transform, power allocation, quasi-analog modulation) and directly transmitted without quantization or coding (entropic or channel). This allows to provide a received video quality directly proportional to the transmission channel quality, without any feedback information, while avoiding the complex adaptation mechanisms of conventional schemes. A first contribution of this thesis is the study of the end-to-end performances of SoftCast. Theoretical models are thus proposed taking into account the bandwidth constraints of the application, the power allocation, as well as the type of decoder used at the reception (LLSE, ZF). Based on a subjective test campaign, a second part concern an original study of the video quality and specific artifacts related to SoftCast. In a third part, preprocessing methods are proposed to increase the received quality in terms of PSNR scores with an average gain of 3 dB. Finally, an adaptive algorithm modifying the size of the group of pictures (GoP) according to the characteristics of the transmitted video content is proposed. This solution allows to obtain about 1 dB additional gains in terms of PSNR scores
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
Etude et optimisation d’un système de vidéotransmission conjoint Source-Canal basé « SoftCast »
No full textLinear video coding (LVC) schemes have recently demonstrated a high potential for delivering video content over challenging wireless channels. SoftCast represents the pioneer of the LVC schemes. Different from current video transmission standards and particularly useful in broadcast situation, SoftCast is a joint source-channel coding system where pixels are processed by successive linear operations (DCT transform, power allocation, quasi-analog modulation) and directly transmitted without quantization or coding (entropic or channel). This allows to provide a received video quality directly proportional to the transmission channel quality, without any feedback information, while avoiding the complex adaptation mechanisms of conventional schemes. A first contribution of this thesis is the study of the end-to-end performances of SoftCast. Theoretical models are thus proposed taking into account the bandwidth constraints of the application, the power allocation, as well as the type of decoder used at the reception (LLSE, ZF). Based on a subjective test campaign, a second part concern an original study of the video quality and specific artifacts related to SoftCast. In a third part, preprocessing methods are proposed to increase the received quality in terms of PSNR scores with an average gain of 3 dB. Finally, an adaptive algorithm modifying the size of the group of pictures (GoP) according to the characteristics of the transmitted video content is proposed. This solution allows to obtain about 1 dB additional gains in terms of PSNR scores.Des nouveaux schémas de Codage Vidéo Linéaire (CVL) ont démontré ces dernières années un potentiel élevé pour la diffusion de contenus vidéo sur des canaux de transmission sans-fil sévères. SoftCast représente le pionnier des schémas CVL. Différent des standards de transmission vidéo actuels et particulièrement utile en situation de broadcast, SoftCast est un système de codage conjoint source-canal où les pixels sont traités par des opérations linéaires successives (transformée DCT, allocation de puissance, modulation quasi-analogique) et directementtransmis sans quantification ni codage (entropique ou de canal). SoftCast permet ainsi d’offrir une qualité vidéo reçue directement proportionnelle à la qualité du canal de transmission, sans aucune information de retour et tout en évitant les mécanismes d’adaptation complexes des schémas classiques. Un premier objectif de ces travaux de thèse concerne l’étude des performances de bout en bout de SoftCast. Des modèles théoriques sont ainsi proposés prenanten compte les contraintes de bande passante de l’application, l’allocation de puissance, ainsi que le type de décodeur utilisé à la réception (LLSE, ZF). Une deuxième partie basée sur une campagne de tests subjectifs concerne une étude originale de la qualité vidéo et des artefacts spécifiques associés à SoftCast. Dans une troisième partie, des méthodes de prétraitement permettant d’accroître la qualité reçue sont proposées avec un gain moyen en PSNR de l’ordre de 3 dB. Finalement, un algorithme adaptatif modifiant la taille du groupe d’images (GoP) en fonction des caractéristiques du contenu vidéo transmis est proposé. Cette solution permet d’obtenir des gains supplémentaires en PSNR de l’ordre de 1 dB
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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