1,720,996 research outputs found
Solitary Waves on Chains of Tensegrity Prisms
No full textIt has been shown that 1-D systems featuring non linear force-displacement response, like, e.g, systems with power law, tensionless response (Nesterenko, 2001, Daraio et al., 2006), support energy transport through solitary waves.
We prove with this study that a similar behavior is exhibited by 1-D chains of class-1 tensegrity prisms in unilateral contact each other, through a numerical approach.
We study the dynamic response of such systems to impulsive loads induced by the impact with external strikers , through numerical integration of the equations of motions of the individual prisms
On the Nonlinear Dynamics of Tensegrity Lattices
No full textIn the present work, we examine a novel application of tensegrity structures, exploring their use as networks supporting energy transport through solitary waves. We show that the elastic potential of a ‘regular minimal tensegrity prism’ (Skelton and de Oliveira, 2010) belongs to the class of nonlinear potentials analyzed in Friesecke and Matthies (2002), which characterize lattices supporting solitary waves with profile dependent on the wave speed. We numerically study the shape of such a profile over a wide range of wave speeds, showing that it localizes on a single lattice spacing (i.e., on a single prism) in the limit for the wave speed tending to infinity. This feature of tensegrity structures has not yet been investigated in the literature, and could pave the way to the use of ‘tensegrity lattices’ (or ‘crystals’) as novel materials to control stress propagation and produce energy trapping (cf., e.g., Fraternali et al. (2010a,b); Daraio et al. (2006) and therein references); innovative tendon- and strut-controlled structures for seismic applications (Skelton, 2002); as well as in novel acoustic devices, in order to create acoustic lenses capable of focusing pressure waves in very compact regions in space (Spadoni and Daraio, 2010)
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
Protection of young children from influenza through universal vaccination
No full textInfluenza is a very common disease among infants and young children, with a considerable clinical and socioeconomic impact. A significant number of health authorities presently recommend universal influenza vaccination for the paediatric population, but a large number of European health authorities is still reluctant to include influenza vaccination in their national vaccination programs. The reasons for this reluctance include the fact that the protection offered by the currently available vaccines is considered poor. This review shows that although future research could lead to an increase in the immunogenicity and potential efficacy of influenza vaccines, the available vaccines, even with their limits, assure sufficient protection in most subjects aged ≥6 months, thus reducing the total burden of influenza in young children and justifying the recommendation for the universal vaccination of the whole paediatric population. For younger subjects, the vaccination of their mother during pregnancy represents an efficacious strategy
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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