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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
Experimental and numerical investigation of the thermal decomposition and the combustion of a lignite porous medium. Application to the safety of chimney ducts
No full textLe présent travail s’inscrit dans le cadre du labCom ANR Optifum. Il concerne l’étude des phénomènes d’incendie dans les conduits de cheminée. Face à la grande diversité des dépôts qui peuvent être impliqués dans de tels sinistres, une étude expérimentale préliminaire a permis d’identifier le lignite comme matériau représentatif. Dans un premier temps, la décomposition thermique du lignite est étudiée à petite échelle. À partir de l'analyse des courbes expérimentales de perte de masse obtenues en analyseur thermogravimétrique, des mesures DSC et de la littérature, quatre mécanismes de pyrolyse sont proposés : un détaillé et trois simplifiés afin de déterminer le niveau de complexité nécessaire à inclure dans le modèle cinétique pour décrire correctement la chimie de la décomposition thermique du lignite. Les modèles numériques ont été validés sous différentes conditions de chauffage avec la détermination des paramètres cinétiques associés aux schémas cinétiques. Ensuite, la décomposition thermique du lignite est étudiée sous atmosphère oxydante. Trois mécanismes réactionnels sont proposés. A l’échelle suivante, des phénomènes supplémentaires tels que les processus de transfert de chaleur et de masse s’ajoutent et doivent être pris en compte. La description de la décomposition thermique nécessite la connaissance de paramètres physiques et thermiques du lignite et du char formé. Ces propriétés sont déterminées expérimentalement et constituent les données d’entrée des modèles. Les quatre modèles de pyrolyse déjà proposés et validés en 0 D sont implémentés en 1 D dans le code PATO. Les résultats numériques de la perte de masse, de la vitesse de perte de masse et des températures à l'aide des 4 modèles sont validés expérimentalement. A échelle croissante nous avons investigué la décomposition thermique et l’inflammation d’un milieu poreux constitué de lignite. Pour cela, trois campagnes d'essais expérimentaux ont été menées. Dans un premier temps, la décomposition thermique du lignite a été étudiée en cône calorimètre à atmosphère contrôlée sous différentes conditions (atmosphère inerte et oxydante, faible et grande puissance…) et structures de lits poreux (taille des particules les constituant). Dans un deuxième temps, un front de gaz traversant à contre-courant le front de pyrolyse a été imposé pour différentes atmosphères (N₂, 10% d’O₂, 18% d’O₂ et 21% d’O₂), puissances et structures de lits poreux. Pour cela, le cône a été modifié spécifiquement pour se positionner dans des configurations et pour des conditions permettant une certaine représentativité des feux au sein des conduits (dynamiques d’écoulement, conditions d’oxygénation, etc.).L’analyse comparative des résultats de la première et de la deuxième campagne montre le rôle important que peuvent avoir la structure du lit poreux et les réactions d’oxydation dans l’accélération de la combustion hétérogène du lignite. La 3ème campagne a été menée avec un dispositif spécifiquement développé et instrumenté à l’échelle du conduit de cheminée, pour ce travail. Les principaux paramètres qui influent le temps d’inflammation et sa sévérité ont été investigués avec la détermination des conditions minimales d’inflammation. Il a aussi s’agit de comprendre la décomposition thermique et la combustion d’un lit de lignite à travers l’analyse des résultats de pertes de masse et les températures associées sous différentes conditions : température d’air, pourcentage d’oxygène, structures du lit de lignite…The present work is a part of the project LabCom ANR Optifum. It concerns the problematic of chimney fires caused by the ignition of the creosote deposits within the chimney duct. A significant heterogeneity exists among these deposits. Thus, an alternative and representative material has been used. The choice of the lignite material has been experimentally validated. At first, lignite thermal decomposition is studied at a very small scale. From the analysis of the experimental curves of mass loss obtained using thermogravimetric analysis, DSC measurements and literature, four pyrolysis mechanisms are proposed, one is detailed and three others are simplified in order to determine the level of complexity necessary to include in the kinetic model to correctly capture the chemistry of lignite thermal degradation. The numerical models have been validated under different heating conditions with the determination of the kinetic parameters corresponding to each kinetic scheme. Then, lignite thermal decomposition is studied under air. Three reaction mechanisms are proposed. With the growth of the scale, additional phenomena such as heat and mass transfer processes are present and must be taken into account. The description of the thermal decomposition process requires knowledge about the physical and thermal parameters of the lignite and the formed char. These properties, which are determined experimentally, constitute the input parameters for the models. The four pyrolysis models that have been already proposed and validated (0D models) are implemented as 1D models in the PATO code. The numerical results of mass loss, mass loss rate and temperatures using the 4 models are experimentally validated.At a larger scale, we have investigated the thermal decomposition and the ignition of a lignite porous medium. For this, three experimental test campaigns have been carried out. Firstly, lignite thermal decomposition has been studied using the Controlled-Atmosphere Cone Calorimeter (CACC) under different conditions (inert and oxidizing atmospheres, low and high heat fluxes, etc.) and structures of porous media (particles sizes). Secondly, a gas crossing the lignite porous medium has been imposed in counter-current to the pyrolysis front under different atmospheres (N₂, 10% d’O₂, 18% d’O₂ et 21% d’O₂), heat fluxes and structures of porous media. For this, the CACC device has been specifically modified to obtain conditions allowing a certain representativeness of chimney ducts fires (flow dynamics, oxygenation conditions, etc.). The comparative analysis of the results of the first and second campaigns demonstrates the important role of the structure of the porous medium and oxidation reactions in accelerating the lignite heterogeneous combustion.The third campaign has been carried out using an experimental bench that has been specifically developed and instrumented at the scale of the chimney duct, for this work. The main parameters influencing ignition time and its severity have been investigated with the determination of the critical conditions of ignition. Moreover, the thermal decomposition and the combustion processes of a lignite porous medium have been deeply understood through the analysis of the mass loss and the associated temperatures results obtained under different conditions: crossing gas temperature, oxygen percentage, structures of the porous medium..
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
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
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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