1,720,966 research outputs found
Topology optimisation for fluid flow and heat transfer applications
Full text linkIn this study, we apply the two most prevalent topological optimisation algorithms to the design of single material heat sinks and heat exchangers. We aim to determine the merits and drawbacks of each method, extend the most suitable method to consider multi-material structures and to subsequently apply this method to design heat recovery structures subject to fluid convection. The two optimisation methods assessed were the density method and the level-set topological optimisation method.
This study presents a review of the current state-of-the-art in topology optimisation, identifying gaps and limitations in current knowledge relating to the application of these methods to fluid-flow and heat transfer problems. Both topological optimisation approaches have been implemented in a numerical framework consisting of a combination of the Matlab package and the Comsol Multiphysics package. The optimisation algorithms have been implemented in Matlab while Comsol is used to perform thermofluid analyses. The implementation has been validated against standard test cases. Comparison of the two methods indicated that the level-set method developed designs performed better than those developed by the density method, and that the level-set method had a number of additional advantages stemming from its superior handling of fluid-solid interface boundary. The relative performance of the approaches is fully discussed.
The level-set approach was extended through implementation of a regular re-initialisation capability to increase the accuracy of interface boundary and through implementation of an adjoint-based sensitivity evaluation to enhance the computational efficiency. This framework is applied to the design of heat-recovery channels, particularly assessing the effect of solid-to-fluid thermal conductivity ratio and flow Reynolds number on the optimised shapes.
This framework is subsequently extended to consider multi-material problems through development of the underlying level-set formulation. The optimal design of copper-aluminium and copper-steel heatsinks are assessed and results and observations are discussed. Potential areas for further works are discussed after drawing conclusions
High-speed low-cost line-field spectral-domain optical coherence tomography for industrial applications
Full text linkThe applications of Optical Coherence Tomography (OCT) systems have been extensively explored in clinical settings and have attracted growing interest in other fields. Factors such as speed and cost are often prioritized over high resolution and power efficiency in industrial applications. Modern OCT systems typically operate at speeds between 20k-70k A-scans/s and are priced at least 3.2k. The reported OCT system provides an axial resolution of 9 μm in air and achieves a maximum on-axis signal-to-noise ratio and sensitivity of 68.8 dB and 88.8 dB, respectively. We demonstrate the practical use of the system by measuring, visualizing, and segmenting samples of Printed Circuit Boards, pharmaceutical tablets, and pea seeds
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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