1,721,003 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
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
Satellite-to-satellite attitude control of a long-distance spacecraft formation for the Next Generation Gravity Mission
Get PDFThe paperpresentsthedesignandsomesimulatedresultsoftheattitudecontrolofasatelliteformation
under studybytheEuropeanSpaceAgencyfortheNextGenerationGravityMission.Theformation
consists oftwospacecraftswhich fly morethan200kmapartatanaltitudefromtheEarth'sgroundof
between 300and400km.Theattitudecontrolmustkeeptheopticalaxesofthetwospacecraftaligned
with amicroradianaccuracy(pointingcontrol).Thisismadepossiblebyspecific opticalsensors
accompanyingtheinter-satellitelaserinterferometer,whichisthemainpayloadofthemission.These
sensors alloweachspacecrafttoactuateautonomousalignmentafterasuitableacquisitionprocedure.
Pointing controlisconstrainedbytheangulardrag-freecontrol,whichisimposedbymissionscience
(Earth gravimetryatalowEarthorbit),andmustzerotheangularaccelerationvectorbelow0.01 μrad/s2
in thesciencefrequencyband.Thisismadepossiblebyultrafine accelerometersfromtheGOCE-class,
whose measurementsmustbecoordinatedwithattitudesensorstoachievedrag-freeandpointing
requirements.EmbeddedModelControlshowshowcoordinationcanbeimplementedaroundthe
embedded modelsofthespacecraftattitudeandoftheformationframequaternion.Evidenceand
discussion aboutsomecriticalrequirementsarealsoincludedtogetherwithextensivesimulatedresults
of twodifferentformationtypes
Model Description and Simulated Mission Performance of the Next Generation Gravity Mission E2E Simulator
No full textIn the years to come, Earth observation via remote sensing will enter into a new era, characterized by a
growing number of advanced and sophisticated satellite missions. They will provide scientists with an
unprecedented capacity to observe and monitor the Earth’s mass transport and its inner physical phenomena.
Following the two successful missions GOCE and GRACE, gravity missions have acquired a great importance
within the ESA Earth Observation Programmes directorate. Indeed, a Next Generation Gravity Mission
(NGGM) concept for measuring the variability of the Earth’s gravity field is proposed, whose objectives will be
very challenging in terms of spatial and temporal resolution. The baseline measurement technique will be a
laser interferometry system via low-low satellite-to-satellite tracking. This space segment will be based on two
drag-free satellites, flying in loose formation in LEO, equipped with a very accurate accelerometer-based
sensing system. The mission concepts and architectures have been implemented in an End-to-End (E2E) multimissions
simulation tool, an evolving simulator platform for the NGGM concept. The paper presents a
description of the main subsystem models of the software simulating a typical NGGM mission scenario, giving
particular attention to the mathematical expression of the relevant embedded models. Considered the specific
thorny points of the mission (the 10 years duration, above all), particular attention is given to the environmental
models, the ion thrusters’ assembly and the drag-free, attitude and orbit control algorithms. In addition, for a
complete validation of the software, series of sensitivity tests have been carried out, mostly involving the
gradiometer, the optical metrology and ion thrusters’ models. These tests have pointed out the different levels of
compliance of the simulated NGGM scenarios against the preliminary mission requirements. Therefore, in the
last part of the paper, a set of guidelines for the enhancement of the control algorithms will be provided, in
order to allow an optimal fitting of the E2E simulator with the latest mission concepts of NGGM
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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