1,721,016 research outputs found
Field evidence and numerical investigation of the Mw = 7.1 October 23 Van, Tabanli and the Mw>5.7 November Earthquakes of 2011
No full textOn Sunday, October 23rd, 2011, the Van province, in the Eastern Turkey, was stricken by a magnitude Mw = 7.2 earthquake. The maximum horizontal peak ground acceleration, i.e. 0.182g, was measured from the seismic station in Muradiye, at about 40km from the epicenter. Several MW > 5.7 strong motion aftershocks were recorded in November 2011. The exceptionally rich sequence of ground motions was due to the dense seismo-tectonic activity of the Eastern Turkey, where many active historical faults exist and newly generated can also be found because of the ongoing continental collision between the Arabian and the Eurasian Plates. The 2011 Van earthquake sequence caused around 700 casualties; the total economic losses are estimated at around 1 billion US dollars.
The present paper deals with the seismological and structural damage assessment of two major seismic events and aftershock sequences in Van region; special emphasis is on the findings of the site investigations performed in the aftermath of the major seismic event. The performed investigation has shown that there is substantial field evidence demonstrating that the losses generated to the local social communities were caused by typical structural and non-structural deficiencies that have been surveyed in the past in several moderate-to-major earthquakes worldwide, especially in poor countries.
Comprehensive numerical simulations were also carried out to assess the characteristics of the strong motion records and their effects on existing representative building type of structures in the earthquake-affected region. It was found that the local building stock is highly vulnerable and requires urgent major structural interventions for seismic strengthening. A cost-efficient retrofitting scheme is however not straightforward. It should be a trade-off between two competing aspects: the use of innovative materials and technologies on one hand, and the low-quality of the workmanships and lack of adequate quality control during construction phase, which are available in the Van province, on the other han
The Selection of Earthquake Records for Pseudo Dynamic Tests of an old Highway Bridge
No full text"Bridges constitute the critical part of transportation systems and their. functionality should be preserved during major earthquakes. The implementation of. comprehensive guidelines for the seismic assessment and retrofit of existing bridges. requires the understanding of complex local and global behavior under moderate to. large earthquakes. The RETRO TA project has been funded by the European. commission within the SERIES project and it focuses on an old portal frame bridge. (Rio-Torto Viaduct), not properly designed for seismic actions. Main objectives of the. current research activity are to assess the seismic vulnerability of Rio-Torto Viaduct. through Pseudo Dynamic (PsD) testing and perform numerical analysis to investigate. the effectiveness of the proposed retrofitting techniques. A proper Seismic hazard. assessment (SHA) is one of the key steps that needs to be conducted to guide the. selection of earthquake ground motion records for nonlinear time-history analysis and. similitude laboratory tests. This paper elaborates the selection and scaling procedures of. the ground motion records within a performance-based design framework as defined in. NTC-08.
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Site characterization by seismic noise in Istanbul, Turkey
No full textSingle station seismic noise measurements were carried out at 192 sites in the western part of Istanbul, Turkey. This extensive survey allowed the fundamental resonance frequency of the sedimentary cover to be mapped, and identify areas prone to site amplification. The results are in good agreement with the geological distribution of sedimentary units, indicating a progressive decrease of the fundamental resonance frequencies from the northeastern part, where the bedrock outcrops, towards the southwestern side, where a thickness of some hundreds meters for the sedimentary cover is estimated. The particular distribution of fundamental resonance frequencies indicates that local amplification of the ground motion might play a significative role in explaining the anomalous damage distribution after the 17 August 1999 Kocaeli Earthquake. Furthermore, 2D array measurements of seismic noise were performed in the metropolitan area with the aim of obtaining a preliminary geophysical characterization of the different sedimentary covers. These measurements allow the estimation of the shear-wave velocity profile for some representative areas and the identification of the presence of strong impedance contrast responsible of seismic ground motion amplification. Comparison of a theoretical site response from an estimated S-wave velocity profile with an empirical one based on earthquake recordings strongly encourages the use of the low cost seismic noise techniques for the study of seismic site effects. (C) 2008 Elsevier Ltd. All rights reserved
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe 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
Get PDFWe 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
- …
