1,721,355 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
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
Contributions à l’étude des exoplanètes : amélioration des mesures de vitesse radiale des étoiles, modélisation de la spectroscopie de transit
No full textLa méthode des vitesses radiales a été la première méthode de détection d'une exoplanète. Depuis 1995, elle a permis de découvrir plus de 2000 exoplanètes et la méthode des RV a ses avantages. Outre la découverte de nouvelles exoplanètes et la détermination de leur masse apparente, elle est utilisée pour confirmer les exoplanètes découvertes par d'autres méthodes et pour mesurer la masse des exoplanètes en transit. Cependant, la méthode RV est limitée par les capacités techniques: la taille et la disponibilité du télescope, la stabilité et la précision de l'étalonnage de la longueur d'onde du spectrographe. Les spectrographes de nouvelle génération sont extrêmement précis d'un point de vue instrumental, ils sont stables et parfaitement calibrés, mais leur précision n'est pas encore suffisante pour détecter une exoplanète jumelle de la Terre. Ainsi, toute amélioration du traitement associé à l'extraction de la RV devrait se traduire par une amélioration de la précision, ou par une réduction du temps de télescope nécessaire pour atteindre une précision définie.Les spectres utilisés pour la méthode des RV étant obtenus à partir de la surface de la Terre, ils contiennent le spectre de l'étoile et le spectre de l'atmosphère terrestre (absorption tellurique). Jusqu'à récemment, les régions spectrales contaminées par l'absorption tellurique étaient exclues du traitement. Après correction, ces régions deviennent disponibles pour être utilisées pour la récupération de RV, améliorant ainsi la précision sur RV. Thèse est consacrée au développement de l'algorithme de correction (basé sur le service web TAPAS), et à l'estimation de l'augmentation de la précision des mesures de RV due à l'augmentation de la gamme de longueurs d'onde disponibles. La méthode de correction a été développée pour l'absorption tellurique causée par O2 et H2O dans le domaine des longueurs d'onde visibles et testée sur les données ouvertes d'ESPRESSO. Pour notre étude de cas de l'étoile HD40307, l'erreur formelle sur la RV est réduite de 0.77 à 0.64 ms-1, ce qui correspond à une économie significative de 45% de temps de télescope.En plus du travail sur la correction de l'absorption tellurique, la thèse se concentre également sur le calcul direct de la RV. 2 méthodes principales existent et sont largement utilisées: la méthode de la fonction de corrélation croisée (CCF) et la méthode du template matching. Il existe également la méthode de Pierre Connes (décrite dans Absolute Astronomical Accelerometry), qui a ses limites en raison de son incapacité à s'appliquer à de grandes variations de vitesse. Dans la thèse, nous proposons et montrons l'application d'une nouvelle méthode, qui est une combinaison de la méthode classique de la CCF et de la méthode de Pierre Connes (PC). Nous proposons d'utiliser la méthode PC pour calculer le changement de RV directement sur la CCF, avec une correction préalable pour le BERV, au lieu de l'ajustement gaussien de la CCF. La méthode a été testée pour les données d'une étoile avec un système planétaire et sans système planétaire, les résultats montrent que la précision du calcul de la RV en utilisant la méthode PC est plus élevée que celle de l'ajustement gaussien. La thèse montre également les débuts d'une correction de l'activité stellaire, basée sur la méthode PC.La deuxième partie de la thèse est consacrée au développement d'un modèle de spectroscopie en transmission pour les exoplanètes telluriques en début de formation. Le développement d'un modèle est particulièrement pertinent après le lancement du JWST et en prévision du lancement d'Ariel, car la plupart des modèles actuels se concentrent davantage sur les géantes gazeuses et les naines brunes. Un modèle d'absorption raie par raie à haute résolution a été développé pour une atmosphère composée de vapeur d'eau H2O et de CO2.The radial velocity method was the first method to detect an exoplanet. Since 1995 it has discovered more than 2000 more exoplanets and, although the transit photometry method is currently the most productive, the radial velocity method has its advantages. In addition to being able to discover new exoplanets and determine their apparent mass msini it is used to confirm exoplanets found by other methods and measure the mass of transit exoplanets. However, the RV method is limited by technical capabilities: the size and availability of the telescope, the stability and accuracy of the wavelength calibration of the spectrograph. New generation spectrographs are extremely accurate from an instrumental point of view, they are stable and perfectly calibrated, but their accuracy is still not enough to detect Earth's exoplanet twin. If it is not possible to improve the instrument the data processing needs to be refined, so any improvement of the processing associated to the radial velocity retrieval should result in an improvement of precision, or in a shorter telescope time required to achieve a defined-goal precision.Because the spectra for the radial velocity method are obtained from the Earth's surface, they contain the spectrum of the star and the spectrum of the Earth's atmosphere (telluric absorption). Until recently, spectral regions contaminated by telluric absorption were excluded from consideration. After telluric correction, those regions become available to be used for RV retrieval, improving the precision on RV.This thesis is devoted to the development of telluric correction algorithm (based on TAPAS web service), describing the telluric correction method and estimating an increase in the precision of radial velocity measurements due to increased available wavelength range. The correction method was developed for telluric absorption caused by O2 and H2O in the visible wavelength range and probed on ESPRESSO open data. For our case study of star HD40307, the formal error on RV is reduced from 0.77 to 0.64 ms-1, corresponding to a significant saving of 45% telescope time.In addition to work on the telluric absorption correction, the thesis also focuses on the direct calculation of the radial velocity. At the moment, there are 2 main methods that exist and are widely used: the cross-correlation function (CCF) method and the template matching method. There is also the Pierre Connes method (described at Absolute Astronomical Accelerometry), which has its limitations due to its inability to be applied to large velocity variations. In this thesis we propose and show the application of a new method, which is a combination of the classical method of cross-correlation function and the method of Pierre Connes (PC). We propose to use the PC method of calculating the change of radial velocity directly on the CCF, with prior correction for BERV, instead of the classical Gaussian fitting of the CCF.The method has been tested for data of a star with a planetary system as well as without a planetary system, the results show that the precision of the radial velocity calculation using the PC method is higher than that of the Gaussian fit. The thesis also shows the beginnings of a stellar activity correction, based on the PC method. As the CCF can be considered an averaged stellar line, counting the change in radial velocity for the left and right wings separately, stellar activity can be analysed.The second part of the thesis is dedicated to the development of a transmission spectroscopy model for telluric exoplanets at the beginning of formation. The development of such a model is particularly relevant after the JWST launch and in anticipation of the Ariel launch, as most current models focus more on gas giants and brown dwarfs. A high-resolution line-by-line model has been developed for an atmosphere consisting of H2O vapour and CO2
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