1,721,011 research outputs found

    Using a cleaning technique for the search of continuous gravitational waves in LIGO data

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    High frequency short events, due for instance to delta-like spurious disturbances, may affect the broad band noise level and thus produce a loss in the efficiency of detection of continuous gravitational waves. We identify such events, remove them from a set of LIGO fifth science run (S5) data and characterize the resulting sensitivity improvements. We use the same parameter values as used in a previous pilot study on Virgo data, but do not observe on LIGO S5 data the same sensitivity improvements

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

    Novel directed search strategy to detect continuous gravitational waves from neutron stars in low- and high-eccentricity binary systems

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    We describe a novel, very fast and robust, directed search incoherent method (which means that the phase information is lost) for periodic gravitational waves from neutron stars in binary systems. As a directed search, we assume the source sky position to be known with enough accuracy, but all other parameters (including orbital ones) are supposed to be unknown. We exploit the frequency modulation due to source orbital motion to unveil the signal signature by commencing from a collection of time and frequency peaks (the so-called "peakmap"). We validate our algorithm (pipeline), adding 131 artificial continuous-wave signals from pulsars in binary systems to simulated detector Gaussian noise, characterized by a power spectral density Sh=4×10-24 Hz-1/2 in the frequency interval [70, 200] Hz, which is overall commensurate with the advanced detector design sensitivities. The pipeline detected 128 signals, and the weakest signal injected (added) and detected has a gravitational-wave strain amplitude of ∼10-24, assuming one month of gapless data collected by a single advanced detector. We also provide sensitivity estimations, which show that, for a single-detector data covering one month of observation time, depending on the source orbital Doppler modulation, we can detect signals with an amplitude of ∼7×10-25. By using three detectors, and one year of data, we would easily gain a factor 3 in sensitivity, translating into being able to detect weaker signals. We also discuss the parameter estimate proficiency of our method, as well as computational budget: sifting one month of single-detector data and 131 Hz-wide frequency range takes roughly 2.4 CPU hours. Hence, the current procedure can be readily applied in ally-sky schemes, sieving in parallel as many sky positions as permitted by the available computational power. Finally, we introduce (ongoing and future) approaches to attain sensitivity improvements and better accuracy on parameter estimates in view of the use on real advanced detector data. © 2017 American Physical Society

    Variations on the Author

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    “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

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    We 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

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    We 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

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We 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
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