1,720,962 research outputs found
Performance-Based Earthquake Engineering Analysis of Short-Medium Span Steel-Concrete Composite Bridges
No full textIn this paper, the results of the performance-based earthquake engineering (PBEE) analysis, carried out to assess the seismic behaviour of short-medium span steel-concrete composite I-girder bridges, are presented and discussed. The selected case study is part of a group of bridges analysed within the SEQBRI project, funded in 2012 by the European Union, which deals with a systematic development of the PBEE analysis for short-medium span steel-concrete composite I-girder bridges. In this respect, fragility and damage analysis of the selected bridge are performed using a proper component-based numerical model along with wide experimental campaign. These outcomes are then integrated in the decision-making analysis, where the selected decision variable is the repair cost ratio of the bridge. The results show the good performances of short medium span steel-concrete composite bridges, both for minor and major damage scenarios
Seismic response mitigation of elevated tanks by HDRB and FPS isolation systems
No full textThe aim of the paper is to evaluate the effectiveness of two isolation systems for the seismic protection
of elevated steel storage tanks: High Damping Rubber Bearings (HDRB) and Friction Pendulum (FPS)
isolators. As a case study, an elevated tank which collapsed during the Kocaeli Earthquake in 1999 at Habas
Pharmaceutics plant in Turkey has been studied. A time-history analysis is conducted using lumped mass
model to demonstrate the high base shear demand and inevitable collapse of support columns due to the
insufficient shear strength. A proper design of HDRB and FPS isolator and a complete non-linear analysis of
the isolated tanks prove the high effectiveness of both isolation systems for reducing the response of the
tank. Results revealed that the tank with the FPS provides better performance compared to HDRB in terms
of the isolation displacement convective base shear demands
Computing resilience of process plants under Na-Tech events: Methodology and application to sesmic loading scenarios
No full textResilience is a performance measure representing both the capability of a system to survive a disruptive event and the ability of rapidly restoring the operational status recovering the initial capacity. However, literature is lacking about methods allowing to compute resilience of process plants from a technical point of view. In fact, in the process industry the scarce literature about resilience mainly focused on organizational issues. In order to contribute to fill this gap a methodology has been developed to estimate resilience in case of Na-Tech events for process plants. The methodology provides a direct estimation of capacity loss after the disruptive event, and the time trend of recovery as well as the related economic loss. The model can be applied both in deterministic and probabilistic manner and is generalizable to any kind of Na-Tech hazard. However, in this paper specific reference is made to seismic hazard. In order to show the capabilities of the methodology a case study is also described referring to a Nitric Acid plant. Results show the predictive capabilities of this approach and the usefulness as a decision making tool for facility planners and emergency managers in the process industry
A probabilistic framework for the estimation of resilience of process plants under Na-Tech seismic events
Full text linkIndustrial plants are complex structures, highly vulnerable with respect to seismic loading. Past seismic events have demonstrated the devastating impact and huge economic losses that an industrial plant can experience not only due to physical damage of equipment, but also due to interruption of the production processes. In order to quantify these economic losses, plant seismic resilience evaluation is required. The current paper presents a probabilistic process flow-based framework for assessment of industrial plant resilience and economic losses in case of seismic events. Uncertainties are considered in the ability of plant equipment to withstand the perturbation, and also in the recovery process including equipment recovery durations and recovery costs. Monte Carlo Simulation is used to account for the uncertainties of the model. A black carbon plant is used as a case study to show the applicability of the model. Results and capability of the proposed model shows that it can be a useful tool for decision makers, plant owners, insurance companies, emergency managers and plant designers in their decision making process
On the resilience calculation of process plants in seismic regions based on Monte Carlo simulation
No full text
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
A novel framework for seismic risk assessment of structures
No full textSeismic risk assessment of new and existing structures has a long history, which is based on the development of specific methods for seismic hazard and vulnerability analyses. Performance-based earthquake engineering is the natural evolution and integration of all these aspects that is nowadays implemented in several precodes. However, some critical aspects are not yet completely clarified. As a matter of fact, the vulnerability analysis suffers the so-called record-to-record variability, which is usually controlled through different parameters used as seismic intensity measures (IMs), whose significance is still under discussion. Moreover, this variability represents an additional source of uncertainty, which is added to the dispersion derived from the ground motion prediction equation (GMPE), leading to an overconservatism. For these reasons, the present paper aims to propose a novel framework for the seismic risk assessment of structures, which is found on the idea to control the response variability in evaluating seismic hazard curves without taking into account the randomness (ε) of the GMPE, which instead is transferred to fragility curves. These latter are built by using groups of accelerograms, whose median and 84% fractile spectra fit well, for different return periods, the uniform hazard spectra for ε= 0 and 1, respectively. For this purpose, a new search algorithm for selecting natural records is formulated. The proposed method offers considerable advantages as it is no longer necessary to refer to a specific IM, and allows to select pairs of spectrum-compatible natural records, which is enable to solve the problem of the seismic assessment of three-dimensional structures. The procedure is then applied to assess seismic risk of a typical reinforced concrete frame, whose results demonstrate the robustness of the method and the practical independence from the record set used
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
- …
