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    Ariane 6: ESA at a crossroads

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    Aerospace Engineerin

    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

    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

    Close-Proximity Operations Concept of the Asteroid Impact Mission

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    The Asteroid Impact Deflection Assessment (AIDA) mission is an international collaboration of ESA and NASA, with the primary goals to test the ability to perform a spacecraft impact on a near-Earth asteroid and to measure and characterize the deflection caused by the impact. The ESA led Asteroid Impact Mission (AIM) is to be designed on a low-cost approach and to be launched in 2020. Its primary objective is to characterize the asteroid 65803 Didymos (1996 GT) and then to assess the consequences of an impact from a NASA provided spacecraft named DART (Double Asteroid Redirection Test) on the secondary asteroid in the binary asteroid system. Prior to the arrival of DART, AIM is planned to rendezvous with the asteroid system in mid-2022. On arrival, AIM would conduct observations that can be used to complement and prepare for the DART impact and perform technology demonstration. In addition, it is planned to release a number of CubeSat opportunity-payload and place the MASCOT-2 lander on the surface of the secondary asteroid. Further, a demonstration of deep space optical communications is planned. AIM is currently studied in the scope of a Phase B1 under ESA contract by two consortia, one of those being led by OHB System. This paper presents OHB's current mission and asteroid operations strategy, addressing mission design and operational challenges. The tight schedule (launch in 2020) and the low cost approach for spacecraft design and operations are challenging, especially in context of the high complexity and performance requirements connected to deep space mission operations and navigation. Special focus is therefore placed on asteroid local operations, the planned payload operations, the deployment of MASCOT-2 to the surface of the secondary asteroid in the binary system, the navigation strategy of AIM, and how OHB plans to overcome the challenges posed by this unique mission scenario

    ESA’s Asteroid Impact Mission: Mission Analysis and Payload Operations State of the Art

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    The Asteroid Impact Mission (AIM) is an ESA mission whose goal is the exploration and study of binary asteroid 65803 Didymos. AIM is planned to be the first spacecraft to rendezvous with a binary asteroid: its mission objectives include the highly relevant scientific return of the exploration as well as innovative technological demonstrations. The paper presents some updates on the ongoing design of the mission. Each phase of the operative life of AIM spacecraft is detailed with information and results on the solutions adopted for Mission Analysis design and on the strategies to suitably operate payloads. The work presented in this paper has been performed by the authors under ESA contract within the phase A design of AIM mission
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