1,721,960 research outputs found
Drake, J. R., 1844- : Confederate Service Record, 1906.
No full textThis service record is an account of military actions during the American Civil War by veteran J. R. Drake (1844- ), dated from 1906.1 leaf ; 2 pdf pages.All descriptive lists and service records in this United Confederate (Civil War) Veterans manuscript collection believed to be based out of Robert E. Lee Camp #158 of the United Confederate Veterans (Fort Worth, Tex.).
United Confederate Veterans. R.E. Lee Camp No. 158 (Fort Worth, Tex.)The Southwest Collection Manuscript Record can be accessed at the following URL: http://www.lib.utexas.edu/taro/ttusw/00119/tsw-00119.htm
The structure of coronal plasma in active stellar coronae from density measurements
Full text linkWe have analyzed high-resolution X-ray spectra of a sample of 22 active stars observed with the High Energy Transmission Grating Spectrometer (HETGS) on Chandra in order to investigate their coronal plasma density, using the lines of the He-like ions O VII, Mg XI, and Si XIII. Si XII lines in all stars of the sample axe compatible with the low-density limit (i.e. n(e) = 10(30) erg/s); O VII lines yield much lower densities of a few 10(10) cm(-3). Our results indicate that the "hot" and "cool" plasma resides in physically different structures.
Our findings imply remarkably compact coronal structures, especially for the hotter (similar to 7 MK) plasma emitting the Mg xi lines characterized by coronal surface filling factor, f(MgXI), ranging from 10(-4) to 10(-1), while we find f(OVII) values from a few 10(-3) up to similar to 1 for the cooler (similar to 2 MK) plasma emitting the O VII lines
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
Is RX J1856.5-3754 a naked neutron star ?
No full textRecent Chandra observations have convincingly shown that the soft X-ray emission from the isolated neutron star candidate RX J1856.5-3754 is featureless and best represented by a blackbody spectrum, in apparent contrast with the predictions of current neutron star atmospheric models. Moreover, the star distance (~120-140 pc) implies a radiation radius of at most ~5-6 km, too small for any neutron star equation of state. Proposed explanations include a reduced X-ray emitting region (a heated polar cap), or the presence of a bare quark/strange star. Here we discuss an alternative possibility. Cool neutron stars (T~1013 G) may be left bare of the gaseous atmosphere by a phase transition in the outermost layers. Computed spectra from bare neutron stars with a surface Fe composition are featureless and virtually indistinguishable from a blackbody in the 0.1-2 keV range. Moreover, owing to the reduced surface emissivity, the star only radiates ~30-50% of the blackbody power and this implies a star radius larger than the radiation radius. Our model can potentially account for the observed X-ray properties of RX J1856.5-3754 and predicts a star radius R∞~10-12 km. The optical emission of RX J1856.5-3754 may be explained by the presence a thin gaseous shell on the top of the Fe condensate
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
- …
