1,721,009 research outputs found
Sensitivity analysis of the GTN damage parameters at different temperature for dynamic fracture propagation in X70 pipeline steel using neural network
No full textSimplified Numerical Tool for a Fast Strength Estimation of Squared Masonry Columns Reinforced with FRP Jackets
No full textThe work addresses the retrofitting of masonry columns with fiber reinforced polymers (FRP) jackets. Experimentation is still at a higher level and the study tries to enrich the set of available numerical models to estimate the capacity of squared masonry columns with a periodic arrangement. The numerical procedure assumes a strain-based incremental formulation relying on equilibrium, compatibility, and kinematic equations and precluding strenuous integration of FEs. An elastic-perfectly plastic response with a Mohr-Coulomb failure criteria has been assumed for both brick units and mortar joints. Failure of the FRP is governed by limited tensile strength and tearing (in the corners of the columns). An associated plastic flow-rule is followed. The numerical strategy has been validated with data from several experimental campaigns, with existing literature approaches and code-based formulas. A good agreement has been found and the strategy demonstrated fast (1–2 s)
Damage Identification in Thin Steel Beams Containing a Horizontal Crack Using the Artificial Neural Networks
No full textThis investigation presents damage identification in thin steel beams containing a horizontal crack using artificial neural networks. In this way, finite element modeling of the cracked beam is developed to generate natural frequencies corresponding to various horizontal cracks scenarios. Then, the artificial neural network is used to create a predictor model for localizing horizontal cracks in steel beams. Results of the current paper show that The proposed technique is an effective method for detecting horizontal crack damage in steel beams. The regression index obtained in this study is equal to 0.979
Forced vibration analysis of laminated composite plates under the action of a moving vehicle
Full text linkThis paper provides a finite element analysis of laminated composite plates under the action of a moving vehicle. The vehicle is modeled as a rigid body with four suspension systems, each consisting of a springdashpot. Overall, the vehicle possesses three degrees of freedom: vertical, rolling, and pitching motions. The equations of motion of the plate are deduced based on first-order shear deformation theory. Using the EulerLagrange equations, the system of coupled equations of motion is extracted and solved by using the Newmark time discretization scheme. The algorithm is validated through the comparison of both the free and forced vibration results provided by the present model and exact or numerical results reported in the literature. The effects are investigated of several system parameters on the dynamic response
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
Enhancing Seismic Resilience of Steel Frames Through GA-Optimized Knee Element Sizing
No full textAs earthquakes pose an ever-growing threat to urban infrastructure,enhancing the seismic performance of steel frames remains a critical challenge.
This study explores the potential of knee-braced steel frames, where knee elements act as dissipative zones, optimized for energy absorption using a genetic algorithm (GA). By focusing on the cross-sectional area of these elements as the design variable, the research aims to maximize hysteretic energy dissipation under seismic loading an essential metric for mitigating structural damage. The methodology integrates finite element simulations to model the nonlinear response of the frames, coupled with a GA to refine the knee element sizing iteratively. Seismic performance is evaluated using dynamic loading conditions representative of earthquake-prone regions, ensuring practical relevance. Results reveal that optimized cross-sectional configurations significantly enhance energy dissipation capacity, improving ductility without compromising overall frame stability. The approach also demonstrates computational efficiency, making it feasible for real-world design applications. Beyond its technical contributions, this work underscores the power of evolutionary algorithms in solving complex structural optimization problems, offering a scalable framework for tailoring dissipative systems to specific seismic demands. These findings pave the way for more resilient steel structures, providing engineers with a tool to balance safety and economy in earthquake-resistant design
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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