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Multi-Scale Seismic Hazard Assessment for Egypt
No full textEgypt is a country with mainly moderate seismicity; it has witnessed strong earthquake impacts along its long history from far-field sources and earthquake impacts from the local. The occurrence of these destructive earthquakes ensures the importance of carrying out a reliable and comprehensive characterization of expected seismic ground shaking, which is essential in order to develop effective seismic mitigation strategies and increase earthquake preparedness for Egypt. So, reliable seismic hazard maps that computed based on correct data and methodology should be prepared for building codes applications; also these maps should be updated when needed.
In the first chapter of this thesis, a review of the existing seismic hazard for Egypt is performed. For the understanding and studying the development of seismic hazard studies for Egypt, we had collected and tested the existing SHA maps, computed at different scales, against the available observations and physical assumptions, data quality, and methodology. Then, we propose some suggestions that could be considered before new seismic hazard maps can be produced and then adopted, for the real benefit of society.
In Chapter 2, an update of seismogenic zones and nodes has been performed, which is needed to perform an updated seismic hazard study for Egyptian territory. We think that the incorporation of seismogenic nodes information side by side with the updated seismogenic zones in the seismic hazard computation may improve performance and usefulness of the resulting maps for the studied region, especially for the sites that have been silent in during the earthquake catalog window show no seismic activity in the catalog so far.
Chapter 3 provides an update for the seismic hazard maps available for Egypt that incorporates recent studies, such as reviewed historical earthquake catalogs, morphostructural zonation data (MZ), revised fault plane solutions and laterally non-varying crustal structure using the neo-deterministic seismic hazard assessment (NDSHA) procedure. Also, a sensitivity analysis of different ground motion maps computed adopting different (a) models for the earthquake source process, (b) crustal structure models of the crust and (c) mapmaker’s preconceptions (e.g., different seismotectonic models), is provided.
In Chapter 4, detailed ground motion modeling for the proper characterization of the amplification patterns (site-effects) along three 2D profiles have been accomplished. The expected amplification patterns range between 2 and 5 and occur at a frequency range 1-7Hz based on the location of the site along the profiles, subsurface geometry and the thickness of the sedimentary layer.
In Chapter 5, we provided the seismic input (response spectra and time histories) that can be applied for the proper evaluation of the dynamic performance of the minaret of the Madrasa the Princess Tatar al-Higaziya, which by role will help in proposing a seismic conservation strategy for this valuable structure. A detailed numerical model for the minaret was established, accompanied with installing ambient sensors for calibrating the numerical model.
The careful assessment of the seismic excitation on the historic minaret through conducting the proposed C-MCSI response spectrum and time history analyses predicts severe damage to the minaret: significant lateral displacements at the minaret top and excessive tensile stress concentration, particularly at the geometric transition zone between the squared base and the hexagon shaft, have been developed. Since the minaret is expected to suffer severe damage against the anticipated scenario of earthquake shaking, a vital protection plan is recommended for the minaret to avoid any future damage or collapse
Site-specific ground motion modeling for a historical Cairo site as a step towards computation of seismic input at cultural heritage sites
Full text linkThroughout time, the area of historical Cairo has been affected by several earthquakes from near and distant seismogenic zones. The maximum earthquake intensity reported in Cairo is VII, on the Modified Mercalli Intensity scale, due to the 1992 Cairo earthquake (Mw=5.9). About 212 Coptic and Islamic monuments were damaged. The spatial distribution of damage, suggests the occurrence of strong local site effects in combination with high vulnerability of the cultural heritage buildings. This study presents the application of a novel seismic hazard analysis approach at a local scale based on physics-based ground motion simulations. A site-specific multi-scenario seismic input (ground motion time histories and response spectra) is computed at a heritage building in Cairo, considering the local site effect. The seismic input is calculated in three steps: a regional scale analysis followed by a site-specific analysis and the combinations of the computed scenarios ground motion. In the regional scale analysis synthetic accelerograms are computed at the site bedrock. Then, the site-specific analysis is performed to calculate the site surface ground motions or response spectra considering the local site effect. Three earthquake scenarios have been considered, characterized by different locations, magnitudes, and fault configurations. The last step consists in the combination of the computed scenario ground motion into one single multi-scenario seismic input specific for the site of interest. This input is represented by spectral ordinates and their variability. For the engineering purpose of time history analysis, the method allows also to extract the computed site specific physics-based accelerograms, requiring no amplitude scaling nor filtering by magnitudes, distances, or site classifications, as usually done with real ground motion records
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
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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