1,720,973 research outputs found
Application of FFTBM with signal mirroring to improve accuracy assessment of MELCOR code
Full text linkThis paper deals with the application of Fast Fourier Transform Base Method (FFTBM) with signal mirroring
(FFTBM-SM) to assess accuracy of MELCOR code. This provides deeper insights into how the accuracy
of MELCOR code in predictions of thermal-hydraulic parameters varies during transients. The case studied
was modeling of Station Black-Out (SBO) accident in PSB-VVER integral test facility by MELCOR code.
The accuracy of this thermal-hydraulic modeling was previously quantified using original FFTBM in a few
number of time-intervals, based on phenomenological windows of SBO accident. Accuracy indices calculated
by original FFTBM in a series of time-intervals unreasonably fluctuate when the investigated signals
sharply increase or decrease. In the current study, accuracy of MELCOR code is quantified using FFTBMSM
in a series of increasing time-intervals, and the results are compared to those with original FFTBM.
Also, differences between the accuracy indices of original FFTBM and FFTBM-SM are investigated and correction
factors calculated to eliminate unphysical effects in original FFTBM. The main findings are: (1)
replacing limited number of phenomena-based time-intervals by a series of increasing time-intervals
provides deeper insights about accuracy variation of the MELCOR calculations, and (2) application of
FFTBM-SM for accuracy evaluation of the MELCOR predictions, provides more reliable results than original
FFTBM by eliminating the fluctuations of accuracy indices when experimental signals sharply
increase or decrease. These studies have been performed in the framework of a research project, aiming
to develop an appropriate accident management support tool for Bushehr nuclear power plant.
2016 Elsevier B.V. All rights reserved
Development and qualification of a thermal-hydraulic nodalization for modeling station blackout accident in PSB-VVER facility
No full texttThis paper deals with the development of a qualified thermal-hydraulic nodalization for modeling StationBlack-Out (SBO) accident in PSB-VVER Integral Test Facility (ITF). This study has been performed in theframework of a research project, aiming to develop an appropriate accident management support toolfor Bushehr nuclear power plant. In this regard, a nodalization has been developed for thermal-hydraulicmodeling of the PSB-VVER ITF by MELCOR integrated code. The nodalization is qualitatively and quan-titatively qualified at both steady-state and transient levels. The accuracy of the MELCOR predictionsis quantified in the transient level using the Fast Fourier Transform Base Method (FFTBM). FFTBM pro-vides an integral representation for quantification of the code accuracy in the frequency domain. It wasobserved that MELCOR predictions are qualitatively and quantitatively in the acceptable range. In addi-tion, the influence of different nodalizations on MELCOR predictions was evaluated and quantified usingFFTBM by developing 8 sensitivity cases with different numbers of control volumes and heat structuresin the core region and steam generator U-tubes. The most appropriate case, which provided results withminimum deviations from the experimental data, was then considered as the qualified nodalization foranalysis of SBO accident in the PSB-VVER ITF. This qualified nodalization can be used for modeling of VVER-1000 nuclear power plants when performing SBO accident analysis by MELCOR code
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
Acquiring the foremost window allocation strategy to achieve the best trade-off among energy, environmental, and comfort criteria in a building
Full text linkThe purpose of this investigation is to propose a way for acquiring the foremost window allocation scheme to have the best trade-off among energy, environmental, and comfort criteria in a building. An advanced decision-making tool, named the technique for order preference by similarity to ideal solution (TOPSIS), is utilized to find the best building amongst different alternatives for having windows on the building façades. Three conditions, namely two parallel, two perpendicular, and three façades, considered as A, B, and C types, respectively, are investigated. For each type, four possible orientations are studied. Heating, cooling, and lighting energy demands in addition to carbon dioxide equivalent emission and thermal and visual comfort are taken into account as the investigated criteria, and they are all evaluated in a simulation environment. The results show that for the modular residential buildings chosen as the case study and located in Tehran, Iran, having windows on the north and east façades is the best scheme. This alternative, which belongs to the B type, has about 40% and 37% lower heating and cooling energy demands than the C type’s foremost alternative. It is also able to provide about 10% better CO2 equivalent emission and 28% higher thermal comfort
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
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