1,720,981 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
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
An Efficient Algorithm for the Synthesis of Laser Altimetry Waveforms
No full textAirborne and spaceborne laser ranging is an emerging technology for capturing data on physical surfaces. An ever increasing number of applications takes advantage of the dense sampling, the high accuracy, and the direct way to obtain 3-D surface points that characterizes laser ranging methods. Most laser altimeters estimate the range to the terrain surface by measuring the round-trip time of flight of a short laser pulse. Laser systems are suitable sensors for rapid surface reconstruction since surface points can easily be computed from the measured range, and from the position and altitude measurements. The small illuminated footprint size and the high precision time measurements ensure reliable ranging and sub-dm vertical range resolution even from orbital altitudes. The heart of the laser system is the laser ranging. The accuracy of the timing (or ranging) performance is governed by the characteristics of the laser system and terrain surface, as well as the waveform processing. Closed form expression describing the shape of the return waveform have been derived only for simple cases, such as flat or uniformly sloping terrain (Gardner, 1982). Laser altimetry simulators are developed to explore the relationship between the altimeter's design, performance and terrain characteristics for more complex surface topography. The Laser altimetry Simulator developed at NASA Goddard Space Flight Center (Abshire et al., 1984) provides a mean for computing the receiver waveform for user defined, arbitrary two-dimensional (height versus along track distance) terrain geometry and for a few, simple 3-D surface types. To investigate the performance of laser systems over complex topography we developed a 3D space-time laser altimetry simulator, which we call Byrd Polar Research Center (BPRC) simulator. This report describes the BPRC simulator. First a brief description of laser altimeter systems is presented followed by the discussion of the characteristics of the returned laser pulse shape for simple surfaces and ranging schemes. The algorithm implemented in the BPRC simulator for waveform computation is summarized in the third chapter. Returned waveforms are presented and compared with results obtained by the NASA/GSFC simulator in the last, fourth chapter
An Algorithm And Application For Visualization And Analysis Of Scanning Laser Altimeter Data
Get PDFIce sheet elevation changes have been measured by repeat airborne laser altimetery in Greenland since 1991. The Airborne Topographic Mapper (ATM) system, which has been mounted in a NASA P-3 aircraft, includes a scanning laser altimeter, INS and differential GPS. During the post-processing the measured data are converted into measurements of ice sheet elevation relative to the Earth ellipsoid (Krabill et aI., 1995). Since laser scanner data sets are composed of a huge amount of points, obtaining the swath contour and locating overlapping areas between different swaths in an efficient way is not a simple task. To make this task more feasible a thinned data set called ICESS has been created from the laser data collected over the Greenland ice sheet (Martin, 1997). Since the surface is reasonably smooth, the laser swath was modeled as a series of planes, each characterized by a center elevation, a north-south slope, and an east-west slope. However, for many applications such as mapping the rough surface of outlet glaciers or surveying urban areas, the original dense laser points are needed. Our major goal is to develop software to access, display, and manipulate the original binary data files. By using a single application the user should be able to determine the overlap between several surveys, compute elevation changes, and create OEMs and contour maps. So far we were mainly focusing on the first part of the job, namely, providing tools for locating the laser swaths and their overlapping areas.
In this report we present the algorithm that we recommend for an efficient contour extraction from laser swaths data and the application that was developed for this purpose. The report is organized as follows. First the major objectives of the development of the algorithm are presented and then the algorithm itself is described. The fourth chapter describes the application functionality, and it is followed by a documentation of the software modules and the installation guide
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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