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Heating of Small Solar System Body Materials
No full textSmall bodies, including asteroid and comet populations, are leftover material from planet formation 4.6 Gya. Near-Earth objects, asteroids and comets with closest approaches to the sun of 2 cm) grains leaving the nucleus. Detailed measurements from ground-based visible-wavelength and radar observations were made of 45P’s inner coma, a region typically too far away to obtain adequate spatial resolution, and/or typically obscured by photodissociation products of the volatile species targeted by this work. Connecting dust grain observations from continuous wave radar with visible imaging of volatile species and smaller dust particles, as well as radar-derived shape models of nuclei, allows for a more holistic understanding of processes occurring in the inner comæ of JFCs
SHOTPUT: A JPL Planetary Summer Science School study
No full textDuring 2015, a unique launch opportunity exists that allows for a New-Frontiers-class mission to discover a compositional gradient of small bodies in our solar system. The proposed seven year mission includes a flyby of main belt asteroid (108144) 2001 HM1, a flyby and impactor release (a la Deep Impact) at the Trojan asteroid (624) Hektor (a suspected contact binary) with companion P/2006, and a flyby with impactor release at the Centaur asteroid 39P/Oterma. The variety of types and positions of these small bodies will help answer some of the fundamental questions we have for the evolution and composition of our solar system. The Jet Propulsion Laboratory (JPL) Planetary Science Summer School team has designed a mission designed to address all of these scientific questions and design objectives. We will describe instrument selection, launch dates and mission timetables, measurement and encounter strategies, impactor design and benefits, data acquisition and communication tradeoffs and provide background into the mission science goals. Furthermore, cost estimates and a work breakdown will be provided to prove the practicality 978-1-4244-2622-5/09/$25.00 copy2009 IEEE. IEEEAC paper #1634, Version 2, Updated Jan 7, 2009 of meeting all the science objectives within a short period of time. A strategy for the development of our system based upon previously used instruments and hardware will also be presented.United States. National Aeronautics and Space Administratio
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Host Galaxies of X-Shaped Radio Sources
Full text linkThe majority of radiation from galaxies containing active galactic nuclei (AGNs) is emitted not by the stars composing the galaxy, but from an active source at the galactic center, most likely a supermassive black hole. Of particular interest are radio galaxies, the active galaxies emitting much of their radiation at radio wavelengths. Within each radio galaxy, an AGN powers a pair of collimated jets of relativistic particles, forming a pair of giant lobes at the end of the jets and thus giving a characteristic double-lobed appearance. A particular class of radio galaxies have an ''X''-shaped morphology: in these, two pairs of lobes appear to originate from the galactic center, producing a distinctive X-shape. Two main mechanisms have been proposed to explain the X-shape morphology: one being through the merger of a binary supermassive black hole system and the second being that the radio jets are expanding into an asymmetric medium. By analyzing radio host galaxy shapes, we probe the distribution of the stellar mass to compare the differing model expectations regarding the distribution of the surrounding gas and stellar material about the AGN
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
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