1,721,094 research outputs found
Strutture in conglomerato cementizio armato - Il fenomeno della delaminazione nel placcaggio con FRP
No full textQuantitative fire risk assessment of road tunnels through advanced consequence analysis
Full text linkThe thesis is focused on the fire risk in road tunnels and its numerical estimation through quantitative risk analysis (QRA) supported by fire and evacuation modeling.
According to the in-force regulations concerning the Trans-European Road Network, the quantitative risk assessment is a mandatory step for existing tunnels that do not comply with the minimum structural safety requirements. When the risk does not reach the acceptability threshold, alternative configurations and mitigation strategies must be designed to reduce the residual risk under a suitable level, and again the QRA is useful to evaluate which choice is the best considering the actual risk reduction, in terms of Expected Value (EV) per year and cost-benefit ratio.
The thesis is divided in three macro-sections, which are intended to provide, on the one hand, an overall view of the complexity of road tunnel systems and, on the other hand, the possibility of a precise estimation of the consequences of a fire event through advanced modeling, in line with the state of the art of the fire safety engineering (FSE). The first section introduces the reader to the topic of fire risk in road tunnels by the characterization of their main features (traffic, systems, etc.), the statistics and the regulations which impose the QRA. In the second section, a detailed description of background aspects of tunnel fire safety is conducted; in addition, parametric studies aimed to assess the capabilities of models in a tunnel context are illustrated. The third section details the proposed methodology for QRA, which is finally applied to two cases studies of unidirectional and bidirectional tunnels
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
On the Assessment of the seismic performance of Reinforced Concrete existing Buildings
No full textLots of reinforced concrete constructions built in Italy up to 1980s have been designed in absence of seismic codes. Therefore, the assessment of their behaviour under earthquake motion and the following seismic vulnerability evaluation is a very key topic. In the present paper, various building designed without considering the seismic action have been analysed pointing out the main parameters influencing their behaviour under earthquake motion and their seismic vulnerability
Shear Connection Nonlinearity and Deflections of Steel-Concrete Composite Beams: a Simplified Method
No full textIn steel and concrete composite beams, the incomplete interaction between steel profile and concrete slab leads to an appreciable increase of the beam deflections with respect to full interaction behavior. Moreover, the concrete cracking in hogging moment regions of continuous beams needs to be considered. In this paper, a finite-element procedure considering nonlinear loadslip relationship for shear connectors is presented. Such a procedure accounts for the concrete slab cracking and the resulting tension stiffening effect; it also assumes different loadslip relationships for shear connectors in cracked slab. Some experimental comparisons show the accuracy of the proposed procedure. A wide parametric analysis is performed with reference to the evaluation of deflections for simply supported composite beams. Finally, a simplified method which is able to evaluate deflections for beams with nonlinear behaving shear connection is presented
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
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