1,720,977 research outputs found
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
Dimethyl ether between 214.6 and 265.3 GHz: The complete, temperature resolved spectrum
Get PDFMade available in DSpace on 2017-07-27T20:15:20Z (GMT). No. of bitstreams: 2
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Previous issue date: 6Made available in DSpace on 2018-01-29T23:02:34Z (GMT). No. of bitstreams: 3
license.txt: 4814 bytes, checksum: a3dad671d2baf2db10a2bec0f2e0c408 (MD5)
2562.pdf: 14758 bytes, checksum: 837da34b69ffb18ecaae08a09889b1cf (MD5)
940254.pptx: 1417506 bytes, checksum: c005890571af256377eab970278319da (MD5)
Previous issue date: 6We have studied dimethyl ether, one of the so-called ‘astronomical weeds’, in the 214.6–265.3 GHz band. We have experimentally gathered a set of intensity calibrated, complete, and temperature resolved spectra from across the temperature range of 238–391 K. Using our previously reported method of analysisfootnote{J. McMillan, S. Fortman, C. Neese, F. DeLucia, ApJ. 795, 56 (2014)}, the point by point method, we are capable of generating the complete spectrum at astronomically significant temperatures. Many lines, of nontrivial intensity, which were previously not included in the available astrophysical catalogs have been found. Lower state energies and line strengths have been found for a number of lines which are not currently present in the catalogs. The extent to which this may be useful in making assignments will be discussed._x000d
MEDIUM RESOLUTION CAVITY SPECTROSCOPY FOR THE STUDY OF LARGE MOLECULES
No full textIt is well known that as molecules become larger the spectral lines of their high-resolution rotational spectra begin to merge, first into modest blends, then into clusters of many lines, and finally into continua. In addition to impacting specificity, the usual signal processing strategies used to separate spectral information from background become ineffective. Medium Resolution Cavity Spectroscopy trades the usual excess of specificity of rotational spectroscopy for a means of obtaining spectra of large molecules with congested or semi-continua spectra. The chief scientific question to be answered is how large (according the several definitions of �large�) can a molecule be and still have structure at medium resolution. The chief technical question to be answered is how to develop strategies to approach white noise sensitivity limits. Experimental details and results, and theoretical results will be presented
MEDIUM RESOLUTION CAVITY SPECTROSCOPY FOR THE STUDY OF LARGE MOLECULES
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1061.pdf: 13312 bytes, checksum: 6193c0366aeabf84398a777fad2baee9 (MD5)
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389387.pptx: 1317413 bytes, checksum: f9bcbf63fcd522390927676b32ab6047 (MD5)
license.txt: 4813 bytes, checksum: 715c4321821a960fa1a1e91d2ac7ebce (MD5)
Previous issue date: 26It is well known that as molecules become larger the spectral lines of their high-resolution rotational spectra begin to merge, first into modest blends, then into clusters of many lines, and finally into continua. In addition to impacting specificity, the usual signal processing strategies used to separate spectral information from background become ineffective. Medium Resolution Cavity Spectroscopy trades the usual excess of specificity of rotational spectroscopy for a means of obtaining spectra of large molecules with congested or semi-continua spectra. The chief scientific question to be answered is how large (according the several definitions of �large�) can a molecule be and still have structure at medium resolution. The chief technical question to be answered is how to develop strategies to approach white noise sensitivity limits. Experimental details and results, and theoretical results will be presented
Thz/mm-wave Spectroscopic Sensors, Catalogs, And Uncatalogued Lines
Get PDF"Analytical chemical sensing based on high resolution rotational molecular spectra has been recognized as a viable technique for decades. We recently demonstrated a compact implementation of such a sensor \footnote{Neese, C.F., I.R. Medvedev, G.M. Plummer, A.J. Frank, C.D. Ball, and F.C. De Lucia, ""A Compact Submillimeter/Terahertz Gas Sensor with Efficient Gas Collection, Preconcentration, and ppt Sensitivity."" Sensors Journal, IEEE, 2012. 12(8): p. 2565-2574}. Future generations of these sensors will rely on automated algorithms for quantification of chemical dilutions based on their spectral libraries, as well as identification of spectral features not present in spectral catalogs. Here we present an algorithm aimed at detection of unidentified lines in complex molecular species based on spectroscopic libraries developed in our previous projects. We will discuss the approaches suitable for data mining in feature-rich rotational molecular spectra."Made available in DSpace on 2014-09-17T16:55:12Z (GMT). No. of bitstreams: 3
license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5)
225.pdf: 15018 bytes, checksum: 1001313e8538f6e9a6a0013c92872e4d (MD5)
abstract.txt: 1175 bytes, checksum: 2e956a484461537ba33b2951c651964b (MD5)
Previous issue date: 2014-06-16Made available in DSpace on 2015-04-14T18:41:48Z (GMT). No. of bitstreams: 4
license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5)
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MJ04_Abstract.pdf: 15018 bytes, checksum: 1001313e8538f6e9a6a0013c92872e4d (MD5)
MJ04_Abstract.txt: 1175 bytes, checksum: 2e956a484461537ba33b2951c651964b (MD5)
Previous issue date: 2014-06-1
The complete, temperature resolved spectrum of methyl cyanide between 200 and 277 GHz
Get PDFWe have studied methyl cyanide, one of the so-called ‘astronomical weeds’, in the 200--277 GHz band. We have experimentally gathered a set of intensity calibrated, complete, and temperature resolved spectra from across the temperature range of 231--351 K. Using our previously reported method of analysis\footnote{J.~McMillan, S.~Fortman, C.~Neese, F.~DeLucia, ApJ. 795, 56 (2014)}, the point by point method, we are capable of generating the complete spectrum at astronomically significant temperatures. Lines, of nontrivial intensity, which were previously not included in the available astrophysical catalogs have been found. Lower state energies and line strengths have been found for a number of lines which are not currently present in the catalogs. The extent to which this may be useful in making assignments will be discussed.Made available in DSpace on 2017-01-26T21:40:02Z (GMT). No. of bitstreams: 3
license.txt: 4848 bytes, checksum: 96035ab3f5e1c23cc7138a224ce498bd (MD5)
1977.pdf: 14596 bytes, checksum: e4938723fa904dcb6b51477898195e2e (MD5)
725559.pptx: 1193978 bytes, checksum: 85a999df0272e460f075f59c687e5e8e (MD5)
Previous issue date: 2016-06-2
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
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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