1,720,964 research outputs found
Optimisation of a Wing-Sail shape for a small boat
No full textOptimisation of the wing sail of a small boat
Use of the CFD for the analysis of the exhausts trajectory
No full textThe problem of the evaluation of the trajectory of the gas exhaust is important in a car project, because its particular impact on the comfort level. For the high performance cars the problem could be critical, because the high level of deceleration of the car during the braking phase.
From the computational point of view the problem appears really challenging. In fact, it is necessary to made an unsteady evaluation, following the car in its velocity history. Furthermore, the geometry representation must be very refined, because the problem is highly related to the small details, and a corrected representation of all the geometrical elements is necessary to avoid an uncorrected analysis of the resulting flow. This imply really high requirements in computational capabilities, and HPC appears essential.
In order to make an assessment of this problem, a numerical procedure, be presented in the present paper, was settled. The numerical procedure is based on the CFD code Ansys-Fluent 14.5, by using a RANS approach with a realizable k-ε model and non-equilibrium wall function.
The reference car is the Ferrari production one. The geometry representation is very refined, and the volume grid is represented by about 60 millions of cells.
Both the time history of the car velocity and the gas mass flow rate are given, defined by means of user-defined functions, and the evaluation was made following them.
The total time of the simulation was 20 s, with a time step of 0.01 s and 10 internal iterations.
In order to analyse the trajectory of the exhaust gas a particle tracking technique was used, by activating the discrete phase model. The injection zone was coincident with the exhausts. As an example, the particle traces at a given time step is shown in fig. 1.
The evaluation was made on a 512 cores cluster in about 4 days.
The results of the numerical evaluation has been confirmed by the analysis of the real behaviour, and the presented results given an important support to define a geometrical set-up suitable to avoid the problem of the interference between the car and the gas exhaust, with a consequent improvement in the comfort level
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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