1,720,973 research outputs found
Experimental evaluation of the flexural behavior of corroded P/C beams
No full textCorrosion phenomena and related effects, such as size reduction in both rebars and strands, bond decay at steel–concrete interface, and cracking in the surrounding concrete, are particularly critical in prestressedconcrete members, not only for safety reasons, but also for their huge potential socio-economic effects. As a matter of fact, this technique has been used for the last 50 years in the majority of viaducts and bridges built in many countries like Italy. In order to evaluate the influence of the corrosion on prestressed pretensioned beams, a number of tests has been carried out in the Laboratory of the University of Rome ‘‘Tor Vergata”. Nine prestressed beams (section size 200 300; total length 3000 mm; clear span 2700 mm) were first subjected to artificial corrosion, to obtain different damage levels, and then were tested in four-point bending. The results clearly show the sizable effects that corrosion has on the ultimate capacity (that is significantly reduced), on the failure mode and on the structural response, that turns from ductile to brittle
Shear performance of existing reinforced concrete T-beams strengthened with FRP
No full textThis paper presents the experimental behaviour of two reinforced concrete (RC) beams strengthened in shear with C-FRP. The beams are extracted from an important building of the '30s in Rome. The goal of this research is to evaluate the shear strength of the retrofitted beams with the simultaneous occurrence of a negative bending moment. The tests are performed at the Experimental Laboratory of the Structural Department of the University "Roma Tre"
Numerical modeling of existing RC beams strengthened in shear with FRP U-sheets
No full textThis paper presents a finite element analysis on two reinforced concrete beams, extracted from an important building of the '30s in Rome, strengthened in shear with C-FRP and subjected to the simultaneous occurrence of a negative bending moment and shear stresses. The commercial program ATENA was used to perform numerical simulations of the tests. The numerical results seem to be in good agreement with the experimental data in terms of load-displacement response, strain state, crack pattern and failure mode
Shear behavior of existing RC T-beams strengthened with CFRP
No full textThis paper presents the experimental behaviour of two reinforced concrete T-beams strengthened in shear with CFRP. The beams are extracted from an important building of the mid-'30s in Rome. The goal of this research is to evaluate the shear strength of the retrofitted beams with the simultaneous occurrence of a negative bending moment. The tests are performed at the Experimental Laboratory of the Structural Department of the University "Roma Tre". In the meantime the two beams are modelled with the software ATENA in order to perform numerical simulations of the tests. The numerical results seem to be in good agreement with the experimental data in terms of load- displacement response, strain state, crack pattern and failure mode
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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