1,721,677 research outputs found
Studies of hadronic B decays with early LHCb data
No full textThe 2010 LHC proton run has provided LHCb with a rich dataset. Several exclusive hadronic B decays are reconstructed with high signal to background ratios. We outline here our strategy for measurements of the angle gamma of the Unitarity Triangle of the CKM matrix
Status of the CHORUS structure function measurement
No full textThe CHORUS detector, designed to search for neutrino oscillations, was used to record a high-statistics sample of neutrino and anti- neutrino interactions during the extension of the experiment in 1998, using the lead calorimeter as a target. The measurement of the structure functions F/sub 2/(x, Q/sup 2/) and xF/sub 3/(x, Q/sup 2/) is underway. (6 refs)
Coherent structures and axial dispersion in bubble column reactors
No full textIn this paper results of measurements of the local and time-dependent behaviour of the two-phase flow; in a bubble column are presented. Measurements with Laser Doppler Anemometry. (LDA) and with glass fibre probes were performed in two homogeneously aerated air/water bubble columns of 15 and of 23 cm dia. These measurements show that considering the flow field as stationary considerably underestimates the velocities present. Although the time averaged liquid velocity profiles resemble textbook data, these averaged values are a result of the passage of coherent structures. LDA measurements showed that these swarms have typical velocities and that at different radial positions. different typical velocities are dominant. The measurements performed with sets of glass fibre probes show that these swarms are typically of the order of the column diameter. indicating that dispersive transport in the axial direction is limited to a distance of approximately the column diameter. Axial dispersion in a bubble column is thus regarded as transport with a typical velocity over a typical distance. A simple model is proposed defining the axial dispersion coefficient as the product of the typical velocities with the column diameter. Agreement of results obtained with this model with existing literature data is good, especially at lower superficial gas velocity conditions
Resonant antineutrino induced electron capture with low energy bound-beta beams
Get PDFAntineutrino induced electron capture is a resonant process that can have a large cross-section for beams of monochromatic antineutrinos. We calculate the cross-section of this process and investigate an experimental setup where monochromatic antineutrinos are produced from the bound-beta decay of fully ionized radioactive atoms in a storage ring. If the energy between the source and the target is well matched, the cross-sections can be significantly larger than the cross-sections of commonly used non-resonant processes. The rate that can be achieved at a small distance between the source and two targets of 10(3) kg is up to one interaction per 8.3a <...10(18) decaying atoms. For a source-target distance corresponding to the first atmospheric neutrino oscillation maximum, the largest rate is one interaction per 3.2a <...10(21) decaying atoms, provided that extremely stringent monochromaticity conditions (10(-7) or better) are achieved in future ion beams
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
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