1,720,989 research outputs found
Vibrations and Buckling of nonlocal laminated nanoplates solved by Finite Element Method
No full textThis work presents a novel finite element (FE) based formulation for analysing the linear buckling and free vibration problems of plates governed by strain gradient theory. The present model is able to deal with general lamination schemes and arbitrary boundary conditions and its validity is tested against semi-analytical results as well as other solutions available in the existing literature. The constitutive relationship deals with stress components at each layer as a function of the nonlocal strains, according to the principles of the aforementioned strain gradient theory. The present FE formulation is based on the weak form of the governing motion equations derived via Hamilton’s Principle. Such principle allows the identification of primary variables which are constitute by classical thin plate displacements as well as their first and higher-order derivatives. Therefore, membrane and bending degrees of freedom must be all approximated by means of Hermite interpolating functions. In particular, Conforming (C) and nonconforming (NC) approaches are consequently developed and compared in the present study in order to test their performances in terms of numerical computations. Validation and novel applications are provided for further studies within the present research topic
Hermite finite elements for the vibrations and buckling of strain gradient nano plates in hygro-thermal environment
No full textNano structural components have been widely spreading recently due to their novel applications in several engineering fields. Such components have a nonlocal mechanical behavior that might force to employ generalized or higher-order elasticity theories to take into consideration effects on the nano scale. In this context, nonlocal strain gradient theory has been utilized for investigating the linear vibrations and buckling phenomena of nano plates where orthotropic mechanical properties are functionalized through the plate thickness. Reinforcing fibers of such orthotropic layers can be modelled by assuming a non-uniform distribution along each ply thickness. The homogenization of the orthotropic layers is performed by following the Halpin–Tsai approach starting from the two main constituents (fiber and matrix). Through-the-thickness functions are introduced to describe the variation of their volume fraction. As an evidence from industrial applications nano plate behavior depends on external stimuli such as hygro-thermal effects. For this reason, these effects have been included into the formulation in order to study their influence in the dynamic and linear buckling phenomena. The governing partial differential equations are solved via a finite element model where Hermitian shape functions are introduced due to the higher-order nature of the nonlocal theory selected which involved both in-plane and out-of-plane displacement parameters. Numerical applications are provided in order to show hygro-thermal effects on the vibration and buckling problems of nano plates, in particular, the effect of the fiber distribution along the ply thickness is underlined
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
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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