1,721,120 research outputs found

    La ricerca della vita nell’Universo

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    Esiste vita altrove nell’Universo? Questa domanda trascende una singola cultura o epoca e accompagna la nostra specie da millenni, ma solo negli ultimi decenni è stato possibile cominciare a cercare risposte nei dati raccolti da strumenti sempre più sensibili e sofisticati

    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

    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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    Nao informado

    Resolution enhancement and interference suppression for planetary radar sounders

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    Orbital radar sounders are an effective tool to investigate the interior of planetary bodies. Typically, the sounding signal lies in the High Frequency (HF) or Very High Frequency (VHF) band, allowing a good ground penetration but a limited range resolution. Moreover, Electromagnetic Interference (EMI) may affect the system, increasing the noise in the radar products.In this paper, we propose methods to enhance the resolution and to suppress the EMI, exploiting a linear prediction based approach. Using simulated data, we investigate the methods’performance and the parameter settings. Finally, we apply the methods to data of the Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS)

    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

    Marsis Radar: the Contrast Method Algorithm

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    It is well known that Mars does not possess an appreciable global magnetic field, by contrast to Earth, which has a strong geomagnetic field of core origin. In these conditions, the solar wind can directly interact with the Martian ionosphere and induce modifications of its local properties, producing a clear distinction between the day side and the night side ionosphere behaviors . This is mainly due to the fact that the day side is directly hit by solar EUV photons which ionize atmospheric neutrals. As a consequence, the use of a radar sounder to analyse the surface and subsurface of Mars, through the ionosphere, must deal with serious constraints, depending on the operative frequencies adopted. In this document, we describe the Contrast Method algorithm used for the on-board and the on- ground processing of the MARSIS radar, in order to compensate the distortions introduced by the Mars ionosphere on the data collected by MARSIS in its subsurface operation mode. We show the effects obtained with the Contrast Method in different environmental. The result is that, the presence of the Contrast Method in the processing pipeline has allowed the collection of relevant scientific data not only during the night side, but also during the day side, producing a substantial improvement of the data quality and the Mars coverage
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