1,721,157 research outputs found
An interval updating model for composite structures optimization
No full textIn practical engineering, the uncertainties commonly exist in the design process of composite structures due to the dispersion of composite materials. This paper proposes an uncertain optimization method based on interval model updating technique and non-probabilistic reliability (NPR) theory. A novel interval model updating method is firstly established by modifying the deterministic constraint condition parameters, which retains the quantification results of the material parameters and has a convinced updating model. In the design section, a new two-step optimization process for composite structures, which combines NPR method and progressive failure theory, is presented based on the updated simulation model. The traditional composite structural design method (safety factor based method) is also introduced to be compared. The NPR based optimization can optimize the nominal value and deviation of the structural response simultaneously, and will achieve a more significant weight reduction effect. A complete process including the uncertainty quantification, interval model updating, NPR based optimization and experimental verification for a composite stiffened plate under the compressive and shear load conditions were performed to verify the effectiveness of the proposed methodology.</p
Theoretical descriptions of nematic polymers, networks and gels
No full textMain-chain and side-chain nematic polymers, nematic networks (the crosslinked polymers) and nematic gels (the swollen networks) have been reviewed in this article. The transition from nematic to isotropic phase, the mean square end-to-end distance of polymers, the rubber elasticity of networks and the phase diagrams of gel systems are all addressed theoretically. (C) 1997 Published by Elsevier Science Ltd.Polymer ScienceSCI(E)EI9REVIEW4735-7642
Corrigendum
No full textWang XJ, Wong SH, Givergis R, Chynn EW. Evaluation of analgesic efficacy of bromfenac sodium ophthalmic solution 0.09% versus ketorolac tromethamine ophthalmic solution 0.5% following LASEK or Epi-LASIK. Clin Ophthalmol. 2011;5:1451-1457.On page 1456 the Acknowledgment section details were incomplete. The corrected Acknowledgment section is: ISTA Pharmaceuticals Inc provided ketorolac tromethamine ophthalmic solution 0.5% and bromfenac sodium ophthalmic solution 0.09% free of charge for this study and monetary compensation to the subjects to encourage participation. Dalton and Associates provided medical editing expertise.Original Articl
Globaltest and GOEAST: two different approaches for Gene Ontology analysis
No full textBackground Gene set analysis is a commonly used method for analysing microarray data by considering groups of functionally related genes instead of individual genes. Here we present the use of two gene set analysis approaches: Globaltest and GOEAST. Globaltest is a method for testing whether sets of genes are significantly associated with a variable of interest. GOEAST is a freely accessible web-based tool to test GO term enrichment within given gene sets. The two approaches were applied in the analysis of gene lists obtained from three different contrasts in a microarray experiment conducted to study the host reactions in broilers following Eimeria infection. Results The Globaltest identified significantly associated gene sets in one of the three contrasts made in the microarray experiment whereas the functional analysis of the differentially expressed genes using GOEAST revealed enriched GO terms in all three contrasts. Conclusion Globaltest and GOEAST gave different results, probably due to the different algorithms and the different criteria used for evaluating the significance of GO terms
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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