1,720,979 research outputs found
Creep behaviour of two-component grout and interaction with segmental lining in tunnelling
Full text linkThe complexity of the two-component grout behavior significantly affects the interaction between the support
system and the tunnel. The loading of the filling material (and also of the segmental lining) takes place during the
curing phase. At the end of it a creep phase develops which shows secondary deformations over time which result
in a relaxation of the segmental lining and an increase in the deformation of the tunnel wall. In this work, a
laboratory experiment campaign allowed to study the two-component material in detail during the creep phase.
The typical trend of deformations over time, obtained for different stress load values and material curing age,
was identified. The maximum stress was also evaluated which still allows to avoid the failure of the material over
time, when a persistent state of stress is applied. The information obtained from the experimentation allowed to
provide considerations on the support system-tunnel interaction, using the convergence-confinement method.
The approach followed was then applied to a real case of a tunnel excavated in Northern Italy, for which it was
possible to estimate the decrease in the load applied to the support system and the increase in deformations of the
tunnel wall due to the creep phenomenon of the two-component material
Design of reinforced ground embankments used for rockfall protection
No full textThe prediction of the effects of rockfall on passive protection structures, such as reinforced ground embankments, is a very complex task and, for this reason, both full-scale tests and numerical dynamic modelling are essential. A systematic set of numerical FEM models, developed in the dynamic field, has been implemented in this work to evaluate the conditions of an embankment that has been subjected to the impact of rock blocks of various sizes at different speeds. These analyses have permitted design charts to be obtained. Furthermore, a simplified analytical approach, based on an equilibrium analysis, has been proposed and its results are compared with numerical data in order to assess its feasibility. A good correspondence between the results has been obtained
Experimental and analytical interpretation of the behaviour of laboratory tests on composite specimens
No full textINT. J. ROCK MECH. & GEOMECH. ABS
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
Improvment of safety conditions of unstable rock slopes through the use of explosives
Full text linkThe paper discusses operations aimed at creating a safer natural or man made rock slope by artificially inducing the displacement of unstable elements by blasting. A detailed analysis of the problems with the use of explosives present when conducting these activities is carried out focusing on the advantages and disadvantages of this technology. The results of two examples of demolition of instable rock elements are presented and discussed thus providing suggestions for future blasting design
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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