1,720,960 research outputs found
A p-adaptive implicit discontinuous Galerkin method for the under-resolved simulation of compressible turbulent flows
No full textIn the last decades Computational Fluid Dynamics has become a widespread practice in several industrial fields, e.g., aerodynamics, aeroacoustic. The growing need of high-fidelity flow simulations for the accurate determination of problem-specific quantities paved the way to higher-order methods such as the discontinuous Galerkin (DG) method. In this context, the industrial interest is strongly promoting the development of more and more efficient high-order CFD solvers. In this work we exploit some techniques, i.e. p-adaptation, quadrature reduction and load balancing, to enhance the computational efficiency of an existing DG code. The accuracy and efficiency of our approach will be assessed by computing the implicit Large Eddy Simulation of the flow past a circular cylinder at Reynolds number Re = 3900, and around a NACA0018 airfoil at Reynolds number Re = 10000 and angle of attack α = 15
Under-resolved simulation of turbulent flows using a p-adaptive discontinuous galerkin method
No full textIn this work we present the main features of a p-adaptive Discontinuous Galerkin (DG) method, suited for the accurate and efficient simulation of turbulent flows. The method allows to locally adapt the polynomial degree of the solution within mesh elements (p-adaptation), obtaining significant reduction of the simulation time and memory, and, at the same time, preserving the high accuracy needed by Direct Numerical Simulations (DNS) and Large Eddy Simulations (LES). Adaptation is driven by a simple error indicator, obtained blending two simple indicators based on
the interface pressure jumps and on the decay of the coefficients of the modal expansion.
Moreover, a load-balancing strategy is adopted during adaptation to achieve good parallel performances. Preliminary results are presented for the under-resolved simulation of the turbulent flows (i) around the NACA 0018 airfoil, Rec = 100 000, M = 0.2 and angle of attack AoA = 10", and (ii) around a rounded leading-edge flat plate (the T3L test case of the ERCOFTAC suite)
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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