1,720,954 research outputs found
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
Numerical and experimental flow analysis of the Wang-Zwische double-lumen cannula
No full textAn experimental and numerical analysis was performed for the Wang-Zwische double-lumen cannula (DLC) (Avalon Elite). The aim of this work was to provide insight for future improvement by characterizing the fluid dynamic behavior of the novel catheter with metrics often associated with blood trauma. Pressure and flow distributions were measured on a steady-flow rig using a 50% glycerol-water mixture by imposing a 2 L/min flow rate across the drainage and infusion lumens. The fluid was modeled as Newtonian with density of 1050 kg/m3 and dynamic viscosity of 0.0035 kg/m·s. Reynolds numbers typical for transitional flow (Re = 2000-2500) were computed within the lumens because of the changing cross-sections of the cannula geometry. Numerical computations were performed using the steady three-dimensional Reynolds-averaged Navier-Stokes (RANS) equations and the low-Reynolds k-ω turbulence model. Discretization of governing equations was based on a cell-centered finite volume method. Numerical results correlated well with global performance of the cannula, allowing evaluation of the geometry toward potential blood trauma. Peak wall shear stress (WSS) in the drainage lumen was higher than that of infusion lumen, mainly due to the presence of side holes. Furthermore, recirculation regions were predicted in transition tubing to connectors of both the drainage and the infusion lumens because of adverse pressure gradients caused by the sudden enlargement of the cannula geometry. In this three-dimensional computational fluid dynamics (CFD) study, we observed higher peak WSS values for the drainage lumen, which may potentially cause blood trauma. Furthermore, recirculation regions were predicted in the proximity of the exit sections of both the infusion and drainage lumens, which may contribute to thrombosis formation. This study provides insight for future DLC modifications in minimizing cannula-induced blood trauma and thrombogenicity in long-term applications. Copyright © American Society of Artificial Internal Organs
Hybrid test bench for evaluation of any device related to mechanical cardiac assistance
No full textAbstract - Hydraulic mock circulatory systems have low flexibility to allow tests of different cardiovascular devices and low precision when a reference model must be reproduced. In this paper a new bench is described. It combines the computer model of the environment in which the device will operate and the electro-hydraulic interfaces by which device and computer are connected. A models library provided with basic functions allows implementing many layouts of the bench, which in turn depend both on the device properties and the desired experiment.
In case of an apical LVAD evaluation, the bench can reproduce right and left ventricles, pulmonary and systemic circulations, inlet and outlet LVAD cannulas. An interface forces the instantaneous calculated flow at the VAD input and feeds back the measured pressure to the computer; another interface works in a similar -but complementary- way at the VAD output.
The paper focuses on the operating principle of the electro hydraulic interfaces which represent a relevant component of the bench, on the RT-Linux-based software architecture, on the models of the basic elements of the bench. A patent is under preparation. At the moment, only a portion of the bench has been developed. It consists of a piston-cylinder mechanism, which mimics the elastance-based mechanism of a natural ventricle, and a hydraulic circuit representing the arterial load according to a modified windkessel model and the venous return according to the Guyton's model. The pump is driven by a real-time simulation of the cardiovascular system. This preliminary layout allowed testing the piston-cylinder mechanism, its control, and the software. This electro-hydraulic interface has been used to reproduce a pulsatile pump working in different modes.
The hybrid model approach can support the development of new cardiac assist devices from their computer model to their manufacture
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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