1,721,117 research outputs found
An intrinsically safe facility for forefront research and training on nuclear technologies - Burnup and transmutation
No full textThe currently dominant open fuel cycles have resulted in the gradual accumulation of (relatively)
large quantities of highly radioactive or fertile materials in the form of depleted uranium, plutonium,
minor actinides (MA) and long-lived fission products (LLFP). For low-activity wastes a heavily shielded
surface repository is required. Spent fuel can be instead directly buried in deep geological repositories
or reprocessed in order to separate U and Pu and eventually also MA and LLFP from other materials.
These elements can be further burnt by modern reactors but not yet in sufficient quantities to slow down
the steady accumulation of these materials in storage. Using ADS, the residual long-lifetime isotopes can
be transmuted by nuclear reactions into shorter-lifetime isotopes again storable in surface repositories.
However, in order to perform transmutations at a practical level, high-power reactors (and consequently
high-power accelerators) are required; particularly, a significant transmutation can be reached not only
by increasing the beam current to something of the order of a few tens of mA, but also by increasing
the beam energy above 500MeV in order to reach the spallation regime. Such high-power infrastructures
require intermediate test facilities with lower power and higher safety level for the investigation of their
dynamics and transmutation capabilities: the ADS proposed in this study could accomplish many of these
constraints
Leading and higher twists in the proton polarized structure function g1p at large Bjorken x
No full textA phenomenological parametrization of the proton polarized structure function g1p(x,Q2) is developed for x≳0.02 using deep inelastic data up to ∼50 (GeV/c)2 as well as available experimental results on both photo- and electroproduction of proton resonances. According to the new parametrization the generalized Drell-Hearn-Gerasimov sum rule is predicted to have a zero-crossing point at Q2=0.16±0.04 (GeV/c)2. Then, low-order polarized Nachtmann moments are estimated and their Q2 behavior is investigated in terms of leading and higher twists for Q2≳1 (GeV/c)2. The leading twist is treated at NLO in the strong coupling constant and the effects of higher orders of the perturbative series are estimated using soft-gluon resummation techniques. In the case of the first moment, higher-twist effects are found to be quite small for Q2≳1 (GeV/c)2, and the singlet axial charge has been determined to be a0[10 (GeV/c)2]=0.16±0.09. In the case of higher order moments, which are sensitive to the large-x region, higher-twist effects are significantly reduced by the introduction of soft gluon contributions, but they are still relevant at Q2∼ few (GeV/c)2 at variance with the case of the unpolarized transverse structure function of the proton. Our finding suggests that spin-dependent correlations among partons may have more impact than spin-independent ones. As a by-product, it is also shown that the Bloom-Gilman local duality is strongly violated in the region of polarized electroproduction of the Δ(1232) resonance
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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