1,721,065 research outputs found
Design and Development of 600 W Proton Exchange Membrane Fuel Cell
No full textThe design of a fuel cell stack is important to achieve optimal output power. This study focuses on the evaluation of a fuel cell system for unmanned aerial vehicles (UAVs). Low temperature proton exchange membrane (LTPEM) fuel cells are the most promising energy source for robot applications because of their unique advantages such as high energy density, cold startup, and quick response during operation. In this paper, a 600 W open cathode LTPEM fuel cell was tested to evaluate the performance and to determine optimal operating conditions. The open cathode design reduces the overall size of the system to meet the requirements for robotic applications. The cruise power requirement of 600 W was supported entirely by the fuel cell while the additional power requirements during takeoff was extended using a battery. A peak of power of 900 W is possible for 10 minutes with a lithium polymer (LiPo) battery. The system was evaluated under various load cycles as well as start-stop cycles. The system response from no load to full load meets the robot platform requirements. The total weight of the stack was 2 kg, while the overall system, including the fuel processing system and battery, was 4 kg.2
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
Knowledge-based industry and regional growth
No full textOne of the most important but less understood phenomena in the beginning of the 21st century has been a shift toward knowledge-based economic activity in the comparative advantage of modern industrialized countries. Two broad trends has been observed in the global economy. That is, the output from the world's science and technology system has been growing rapidly and the nature of investment has been changed (MILLER, 1996). The relative proportions of physical and intangible investment have changed considerably with the relative increase of intangible investments since the 1980s. In addition, there has been increased complementarity between physical and intangible investments and more important role of high technology in both kinds of investment (MILLER, 1996). Even in the newly industrialized countries, the growth of technology intensive industries, the increase of R&D activities and the growth of the knowledge intensive producer services have been common feature in recent years. In this change of the structure of productive assets, the role of knowledge is well recognized as the most fundamental resources in recent years (OECD, 1996; WORLD BANK, 1998). The development of information and communication technology (ICT) and globalisation trend have promoted this shift toward knowledge-based economy
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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