1,720,961 research outputs found
Effects of different test apparati and heating procedures on the bond properties of post-installed rebar connections under elevated temperatures
Full text linkThe use of chemical bonds to fasten reinforcement bars in existing concrete structures has been widely developed in the previous years, showing in many cases higher bond values compared to cast in rebars due to better performance of the adhesive mortar. However, at elevated temperatures the concrete-adhesive bond tends to weaken endangering the construction under a fire situation. The paper presents the result of an experimental campaign carried out at Scientific and Technical Center of Building and Politecnico di Milano laboratories on a post-installed connection using vinyl-ester polymer. This paper aims to investigate the behavior of rebar connections through chemical resin when subjected to high temperatures, with particular emphasis on the effects of water vaporization in the concrete and on the influence of heating procedures on the mortar post-curing. Two different pull-out test procedures were adopted, differentiating each other for the loading and heating sequences. Results showed that specimens with the same water content may present different thermal gradients; however, comparable mean temperatures along the bar are detected for the same values of applied load. Moreover, for a given temperature, the increase of bond strength with exposure time showed a convergence towards an asymptotic value
Derivation of an innovative testing protocol for plastic anchors for fixing light façade claddings under seismic action
No full textThe safety of buildings located in seismic zones is related to the proper design of both the structural and
the non-structural components. In recent seismic events, the collapse of the non-structural parts clearly
demonstrated how they may represent a risk not only for the life safety but also the majority of the economical
losses. Light cladding panels are a common solution to built façades in framed systems with rigid infills,
particularly in reinforced concrete structures with masonry walls. They are usually fixed to the supporting
structures by means of plastic anchors through angle brackets. Within this context, an experimental campaign
was carried out to investigate their behaviour under seismic action. Starting from dynamic tests on real size
façades, a new test protocol was proposed for the assessment of plastic anchors for fixing façade claddings.
The scope of the present paper is to provide a theoretical background for the aforementioned test protocol
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
On the structural behavior of reinforced concrete walls exposed to fire
No full textThe present work deals with numerical simulations concerning the international benchmark "Vulcain tests on 3 Walls" regarding fire tests conducted in CSTB in Paris, France. To this aim, sequentially-coupled thermo-mechanical analyses have been performed on three reinforced concrete walls, characterized by different load levels and boundary conditions. The numerical results show that the imposed compressive load and boundary conditions significantly influence the magnitude of the displacements. In the case of simply supported walls, the wall with the lower load level exhibited a gradual and monotonic increase of the displacements at mid-height (both in the tests and in the numerical analyses), while the wall with the higher load level exhibited a displacement reversal due to second-order effects after approximately 60 minutes of fire exposure. This reversal, which was obtained in the analyses, was not observed in the test. Load bearing capacity of all the three specimen walls was maintained in such a way that the collapse did not take place during two hours of fire exposure
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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