1,720,969 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
New low band-gap alternating polyfluorene derivatives for photovoltaic cells
No full textBulk heterojunction polymer photovoltaic cells (PPVCs) were fabricated by using low energy band-gap conjugated polymers (PFR3-S and PFR4-S) as electron donors and C-60 as an electron acceptor material. The characterization of the structures of the PFR3-S:C-60 and PFR4-S:C-60 mixtures were carried out with atomic force microscopy (AFM), and the PPVCs were characterized with current density-voltage (J-V) and spectral photocurrent measurements. The PFR3-S:C-60 (1:1) and PFR4-S:C-60 (1:1) devices were constructed in ITO/PEDOT:PSS (100 nm)/polymer:C-60 (100 nm)/Ca (50 nm)/Al (100 nm) configurations. In the PFR4-S:C-60 PPVC, the spectral response was found to be extended to 700 nm, and exhibited an improved spectral match with solar radiation. The PFR3-S:C-60 (1:1) and PFR4-S:C60 (1:1) devices were found to have higher energy conversion efficiencies and better short circuit current densities (J(sc)), 3.18 mA/cm(2) and 3.09 mA/cm(2), respectively, than a MEHPPV:C60 (1:1) device. The open-circuit voltages (V-oc) of the PFR3-S and PFR4-S devices were found to be 0.85 and 0.81 V, respectively. The energy conversion efficiencies (eta(e)) of the PFR3-S:C-60 (1:1) and PFR4-S:C-60 (1:1) devices under AM 1.5 solar illumination (100 mW/cm(2)) were found to be as high as 0.98% and 1.02%, respectively. (c) 2005 Elsevier B.V. All rights reserved
A study of the hydrostatic extrusion of copper-clad aluminium tube
No full textThis paper is concerned with the hydrostatic extrusion process of copper-clad aluminium tube. In this study, the rigid-plastic finite-element method is used to analyze the steady-state extrusion process of the bimetal tube. Simulations are performed for copper-clad aluminium tube to give the distributions of the effective strain rate, equivalent stress and hardness for some extrusion ratios and die angles. In addition, the interface profile of the bimetal tube is predicted by tracking a particle path at the interface in the Eulerian domain. Experiments are carried out for copper-clad aluminium tube at room temperature. It is found that the finite-element predictions are generally in good agreement with the experimental observations. Detailed comparisons of the extrusion loads and interface profiles by the finite-element method with those from experiment are given. (C) 1997 Elsevier Science S.A
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
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