1,720,958 research outputs found
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
Development Of Computational Fluid Dynamics (CFD) Based Erosion Models For Oil And Gas Industry Applications
No full textErosion prediction plays a critical role in different oil and gas industry segments including drill bit manufacturing, measurement & logging while drilling (M&LWD), and reservoir engineering/completions tools. Recently, Computational Fluid Dynamics (CFD) is used to predict erosion due to multiphase flows in complex geometries. Currently used CFD-based erosion models are able to predict erosion regions fairly accurately in various applications but they are highly inaccurate when it comes topredictions of quantities like erosion rate. Predicted quantities within an order of magnitude of the measured values are common and may be considered acceptable for many applications in the industry simply because more accurate prediction tools do not exist. This research aims at developing a more robust and accurate CFD-based erosion model and formulating best practice CFD guidelines for the application of the model. An extensive set of experimental data was made available by Baker Hughes for experiments conducted on a 900 elbow. The present Baker Hughes erosion model was studied and modified to better fit the experimental data. The model was prepared for low sand concentration (1-10%) applications and was validated by comparing the predicted erosion region to that observed in the experimental results. Effect of various computational turbulence models and wall treatments were studied. A grid convergence study was performed to see the effect of near wall resolution on erosion prediction accuracy. Just by improving the CFD modeling approach, the mean percentage error decreases from around 60% to 40%. A statistical analysis was performed on the CFD output parameters to identify the parameters that effect erosion rates the most. Correlation analysis and non-parametric statistical analysis was carried out. Various regression models were employed for approximating the erosion rates as a function of the identified parameters. A new model specific to different y+ range was proposed and a considerable decrease in mean percentage error was observed. Two new regression models based on turbulent kinetic energy and surface shear stress were also developed. They provide excellent results with a further decrease in mean percentage error to around 30%. Finally, an artificial neural network model was developed. A multilayer feedforward model with backpropogation algorithm and Levenberg-Marquardt training was used. The model gave a mean error percentage of less than 30%. Bayesian regularization was used with the training algorithm to avoid over fitting of the model. This model with regularization gave less than 10% mean percentage error for 920 data points
A Low Cost Micro Scale Cyclone Seperator- Design And Computational Fluid Dynamics Analysis
No full textMicroparticle separation process has a variety of application varying from application in biological and biomedical industries for analysis and diagnosis, in biogas manufacturing to separate phases as well as in defense sector for detection of biological weapons like anthrax. Available electrical, magnetic, acoustic and various other methods are either very costly or not portable. The proposed design of micro scale cyclone separator is low cost as well as portable and easy to manufacture. Huge cyclone separators are widely used in various industries since decades but due to lack of research in micro scale cyclones no direct and sufficient data is available. This research attempts to develop a microscale cyclone separator and study the effect of parameters like inlet velocity on pressure drop in a micro scale cyclone separator. It further studies the effect of particle size on collection efficiency through Computational Fluid Dynamics (CFD) approach.CFD analysis has been proved very efficient for calculations in larger cyclones and hence is used as a tool in this study as well, though experimental verification is recommended. Computational experiments were performed using FLUENT. The results obtained are compared with various empirical relations developed for huge cyclone separators and similarities and dissimilarities in trends are analyzed. Finally a multi-cyclone model is proposed to obtain higher collection efficiency
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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