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[Palestine Ry., Engine Drawing Card, Sketch No. 7219]
No full textThis engine drawing card was created for Palestine Railway, Class 8-34-D. Section J-8-D. Sketch 7219. Copy Spec. 22-F-138
ATCA Study of Small Magellanic Cloud Supernova Remnant 1E 0102.2-7219
Get PDFWe present new and archival Australia Telescope Compact Array and Atacama
Large Millimeter/submillimeter Array data of the Small Magellanic Cloud
supernova remnant 1E 0102.2-7219 at 2100, 5500, 9000, and 108000 MHz; as well
as Hi data provided by the Australian Square Kilometre Array Pathfinder. The
remnant shows a ring-like morphology with a mean radius of 6.2 pc. The 5500 MHz
image reveals a bridge-like structure, seen for the first time in a radio
image. This structure is also visible in both optical and X-ray images. In the
9000 MHz image we detect a central feature that has a flux density of 4.3 mJy
but rule out a pulsar wind nebula origin, due to the lack of significant
polarisation towards the central feature with an upper limit of 4 per cent. The
mean fractional polarisation for 1E 0102.2-7219 is 7 +- 1 and 12 +- 2 per cent
for 5500 and 9000 MHz, respectively. The spectral index for the entire remnant
is -0.61 +- 0.01. We estimate the line-of-sight magnetic field strength in the
direction of 1E 0102.2-7219 of ~44 microG with an equipartition field of 65 +-
5 microG. This latter model, uses the minimum energy of the sum of the magnetic
field and cosmic ray electrons only. We detect an Hi cloud towards this remnant
at the velocity range of ~160-180 km s-1 and a cavity-like structure at the
velocity of 163.7-167.6 km s-1. We do not detect CO emission towards 1E
0102.2-7219
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
A Detailed Archival CHANDRA Study of the Young Core-collapse Supernova Remnant 1E 0102.2-7219 in the Small Magellanic Cloud
No full textWe present an archival Chandra study of the O-rich supernova remnant (SNR) 1E 0102.2-7219 in the Small Magellanic Cloud. Based on deep similar to 265 ks archival Chandra data, we performed a detailed spatially resolved spectral analysis of 1E 0102.2-7219. Our aim is to reveal the spatial and chemical structures of this remnant in unprecedented detail. Radial profiles of O, Ne, and Mg abundances based on our analysis of regional spectra extracted along nine different azimuthal directions of 1E 0102.2-7219 suggest the contact discontinuity at similar to 5.5 pc from the geometric center of the X-ray emission of the SNR. We find that the metal-rich ejecta gas extends further outward to the west and southwest than in the other directions of the SNR. The average O/Ne, O/Mg, and Ne/Mg abundance ratios of the ejecta are in plausible agreement with the nucleosynthesis products from the explosion of a similar to 40 M-circle dot progenitor. We estimate an upper limit on the Sedov age of similar to 3500 yr and explosion energy of similar to 1.8 x 10(51) erg for 1E 0102.2-7219. We discuss the implications of our results for the geometrical structure of the remnant, its circumstellar medium and the nature of the progenitor star. Our results do not fit with a simple picture of the reverse-shocked emission from a spherical shell-like ejecta gas with a uniformly distributed metal abundance and a power-law density along the radius of the SNR
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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
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