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Use of statistically designed experiments to explore sensitivities in the strength scaling of FRP composites.
No full textSize and scale effects in composites: II. Unidirectional laminates
No full textThis paper is concerned with the scale and size effects in the strength characterisation of composite materials with particular reference to hand laid-up unidirectional laminates. Attention has been focused on the tensile and flexural strengths of glass/epoxy and carbon/epoxy laminates. The experiments have been designed through the use of statistical, factorial-based techniques, whereby a more comprehensive analysis of the inter-relationship between different parameters and their influence on strength can be made. The work highlights the importance of fabrication factors and the distinguishing difference between scale effects and size effects
Size and scale effects in composites: I. Literature review
No full textThis paper is concerned with a review of the size and scale effects involved in the prediction of strength of fibre-reinforced-plastic (FRP) composite materials and structures. The review covers the basic principles in the establishment of scaling laws and the application of the Buckingham-Pi theorem. An analysis of various theories used in categorising size effects, such as the weak link, extended weak link and fracture mechanics approaches, is presented. This is followed by an examination of the literature devoted to scaling issues in FRP composites
Size and scale effects in composites: III. Woven-roving laminates
No full textThis paper is concerned with scale and size effects in the strength characterisation of composite materials with particular reference to woven-roving laminates. Attention has been focused on the tensile and flexural strengths of glass/polyester laminates fabricated by hand lay-up techniques. Factorial experiments have been designed to allow investigation of the joint influence of different factors on strength. The work highlights the importance of fabrication factors and the distinguishing difference between scale effects and size effects
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
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