1,721,098 research outputs found
degrading Bouc-Wen model parametrers identification under cyclic load
No full textThe Bouc–Wen model of hysteresis is used in structural engineering to describe a wide range of
nonlinear hysteretic systems, as consequence of its capability to produce a variety of hysteretic
patterns. This research focuses on the application of the Bouc–Wen model to predict the hysteretic
behaviour of reinforced concrete bridge piers. The purpose is to identify the optimal values of the
parameters so that the output of the model matches as well as possible the experimental data. Two
repaired and retrofitted reinforced concrete bridge pier specimens (in a 1:6 scale of a real bridge pier)
tested physically in a laboratory are considered in this paper. An identification of Bouc–Wen model’s
parameters is performed using the force–displacement experimental data obtained after cyclic loading
tests on these two specimens. The original model involves many parameters and complex pinching
and degrading functions and this makes the identification solution unmanageable and with numerical
problems. Furthermore, from a computational point of view, the identification takes too much time.
The novelty of this work is the proposal of a simplification of the model allowed by: simpler pinching
and degrading functions; reduction of the number of parameters. The latter innovation is much
effective in reducing computational efforts and is performed after a deep study of the mechanical
effects of each parameter on the pier response. This simplified model is implemented in a MATLAB
code and the numerical results are well fitting the experimental ones and are reliable in terms of
manageability, stability, and computational time
Robust design of tuned liquid column dampers under stochastic ground motion considering fuzzy uncertainties
No full text
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
Soft Computing Applications in Structural Dynamic Monitoring
No full textSoft computing based tools and methodologies are attracting growing interest in the field of structural dynamic monitoring. Within this framework, neural networks, evolutionary computation,metaheuristic and swarm intelligence are becoming very popular in sensor network design, signal processing, system identification, model updating and structural diagnostic. Current research also shows increasing use of fuzzy logic for damage detection and structural diagnostic. The paper provides a short state-of-the-art review about the most recent research on soft computing theories and techniques for structural dynamic monitoring, with the focus on optimal sensor placement, mechanical system identification and health monitoring. Finally, some experimental applications are included to highlight how soft computing methods can be employed effectively in this field. They are concerned with the experimental parametric identification of nonlinear passive devices for seismic protection using differential evolution and particle swarm optimization
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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