1,721,029 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

    Simulation de la dynamique spatiale et temporelle du rayonnement transmis par une strate arborée d'une parcelle agroforestière. Confort thermique des ruminants en sylvopastoralisme

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    MasterManagement of the microclimate and shading generated by trees in an agroforestry plot is a potential means of adapting sheep farming systems to thermal stress caused by temperature increases. This study aims to investigate the transmission of incident radiation through the tree canopy and to characterize the spatio-temporal dynamics of the generated shading. To do so, a simulation approach using the Heterofor model hosted on the Capsis platform was chosen. The performance of the model was evaluated on two agroforestry plots, one with intra-plot trees (cherry and sycamore) and border trees, and the other with ash trees in a high hedge. The model makes satisfactory estimates of transmitted radiation (NSE: 0.75 to 0.83 and bias: -2 to 6%). The inaccuracies identified come from both the model and the data. From the simulations, hourly or averaged shading indicators (area or duration) were calculated and spatialized in the form of georeferenced maps. The sensitivity of these indicators to tree configuration, slope and exposure was then investigated. The heat load index (HLI), calculated from the transmitted radiation, show that the trees have a localized buffering effect on the thermal environment of the plotsLa gestion du microclimat et de l’ombrage générés par les arbres d’une parcelle agroforestière est un potentiel moyen d’adaptation des systèmes d’élevage ovins au stress thermique provoqué par des hausses de température. Cette étude vise à étudier la transmission du rayonnement incident à travers le couvert arboré et à caractériser la dynamique spatio-temporelle de l’ombrage généré. Pour ce faire, une approche par simulation via l’utilisation du modèle Heterofor hébergé sur la plateforme Capsis a été choisie. La performance du modèle a été évaluée sur deux parcelles agroforestières dont l’une avec des arbres intra-parcellaires (merisiers et érables sycomores) et des arbres debordure, et l’autre avec des frênes en bordure en forme de haie haute. Le modèle fait des estimations satisfaisantes du rayonnement transmis (NSE: 0.75 à 0.83 et biais: -2 à 6%). Les imprécisions identifiées viennent à la fois du modèle et des données. A partir des simulations, des indicateurs d’ombrage (surface ou durée) horaires ou moyennés, ont été calculés et spatialisés sous forme de cartographies géoréférencées. La sensibilité de ces indicateurs à la configuration des arbres, la pente et l’exposition a ensuite été investiguée. Les indices de charge thermique (HLI), calculés à partir du rayonnement transmis, montrent que les arbres ont un effet tampon localisé sur l’ambiance thermique des parcelle

    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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    Contribution to the study of the wetting time within an apple tree canopy

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    La pomme, fruit le plus cultivé sur le sol français, est principalement menacée par le pathogène Venturia inaequalis, responsable de la maladie de la tavelure qui génère des pertes considérables si elle n'est pas traitée. La politique actuelle de gestions des risques phytopathologiques en France incite à une forte réduction des traitements phytosanitaires tout en maximisant le rendement et la qualité des productions. Dans ce contexte, il apparaît indispensable de mieux comprendre les interactions entre l'arbre, son pathogène, et leur environnement, qui s'articulent pour le cas de la tavelure du pommier autour de la durée d'humectation des feuilles. Au cours de ce travail nous nous sommes intéressés à ce paramètre pour essayer de mieux comprendre les interactions entre microclimat de l'arbre et durée d'humectation. L'étude s'est déroulée en trois étapes majeures : la modélisation de l'évaporation d'une goutte sur un support végétal, l'étude expérimentale de la mouillabilité des feuilles de pommier, et l'étude expérimentale de la variabilité spatiale de la durée d'humectation sous un couvert de pommiers. Ce travail a permis d’expliciter la forte variabilité intra-couronne de la durée d'humectation via la prise en compte de la structure de l’arbre et de la dynamique horaire du microclimat. Le modèle développé, au delà des liens déjà connus entre l’intensité du flux évaporatif et les variables climatiques, a montré la sensibilité importante du temps d’évaporation à la mouillabilité du support via la forme de la goutte d’eau, mettant en avant la nécessité de quantifier au mieux cette interaction goutte support via l’estimation des angles de contact statiques et dynamiques.Apples, which are the most cultivated fruit in France, are mainly endangered by the fungal pathogen Venturia inaequalis that cause apple scab disease on apple. This disease can be responsible of major products loss unless orchards are treated against apple scab. Nowadays in France, the phytopathological diseases management policies are encouraging growers to reduce considerably the use of pesticides, while keeping a high quality and yield level. In this context, one must understand better how the plant, the pathogen and their environment, interact with each other: for apple scab, the most important environmental parameter is leaf wetness duration. During this work, we studied leaf wetness duration to understand the interactions that occur between the tree microclimate and the wetness duration. To do that we divided our work in three major steps : the modeling of evaporation of a droplet at rest on a leaf, the experimental study of apple leaves wettability, and the experimental study of wetness duration spatial variability within an apple trees orchard. This study led us to clarify the strong intra-crown variability of leaf wetness duration through the consideration of tree structure and hourly dynamics of microclimate. The model we developed, beyond the known links between the evaporative flux intensity and the climatic parameters, showed a strong sensibility of the evaporation duration to the substrate wettability, highlighting the necessity to quantify at best this interaction, through the estimation of static and dynamic contact angles

    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
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