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Implementación de bases geoespaciales para la vulnerabilidad sísmica de edificios de concreto armadoPalacios Castro, Harold Jesús Alberto, Pérez Elias, Kevin Jorge January 2015 (has links)
Nuestro país se encuentra ubicado en una zona de alta actividad sísmica, por ello es importante que los ingenieros civiles tengan una adecuada capacidad para realizar análisis de vulnerabilidad sísmica y comprendan la importancia de la prevención. En la presente tesis analizamos los diferentes escenarios de daño sísmico para edificios de concreto armado organizados por tipología de número de pisos.
Para el desarrollo de la presente investigación utilizamos dos Software, el primer software de simulación sísmica, en el cual modelamos la muestra de edificaciones de concreto armado que representan el distrito de Santiago de Surco, para luego analizarlo con un sismo de tiempo historia que simula varias magnitudes del mismo sismo amplificado con aceleraciones del suelo que varían de 0.1g a 1.0g, con el objetivo de obtener cada vez mayores desplazamientos, y de esa manera mayores niveles de daño mediante la metodología Hazus M-H. Luego estos valores expresarlos en cuadros de curvas de fragilidad sísmica con cuatro tipos de niveles de daño. El Segundo Software que utilizamos es el Sistema de Información Geográfica (SIG), con este programa sistematizamos los datos obtenido de la curva de fragilidad para mostrar mapas de niveles de daño para distintos escenarios sísmicos que muestren el comportamiento de los edificios al ocurrir un evento sísmico.
Our country is located in a zone of high seismic activity, it is important that civil engineers have adequate capacity for analysis of seismic vulnerability and understand the importance of prevention. In this thesis we analyze the different scenarios of seismic damage to reinforced concrete buildings organized by type of number of floors.
For the development of this research we use two software, the first seismic simulation software, which model the sample of reinforced concrete buildings representing Santiago de Surco, and then scan it with an earthquake simulating various weather history amplified earthquake magnitudes thereof with ground accelerations ranging from 1.0g 0.1ga, in order to obtain increasing displacement, and thus higher levels of damage by HAZUS MH methodology. Then these values express them in boxes seismic fragility curves with four types of damage levels. The second software we use is the Geographic Information System (GIS), with this program systematize data obtained fragility curve to display maps for different levels of damage scenarios showing the seismic performance of buildings to a seismic event occur.
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Seismic Damage Assessment of Reinforced Concrete Frame Buildings in CanadaAl Mamun, Abdullah January 2017 (has links)
The emphasis on seismic design and assessment of reinforced concrete (RC) frame structure has shifted from force-based to performance-based design and assessment to accommodate strength and ductility for required performance of building. RC frame structure may suffer different levels of damage under seismic-induced ground motions, with potentials for formation of hinges in structural elements, depending on the level of stringency in design. Thus it is required to monitor the seismic behaviour and performance of buildings, which depend on the structural system, year of construction and the level of irregularities in the structural system. It is the objective of the current research project to assess seismic performance of RC frame buildings in Canada, while developing fragility curves as analytical tools for such assessment. This was done through dynamic inelastic analysis by modelling selected building structures and using PERFORM-3D as analysis software, while employing incremental dynamic analysis to generate performance data under incrementally increasing seismic intensity of selected earthquake records. The results lead to probabilistic tools to assess the performance of buildings designed following the National Building Code of Canada in different years of construction with and without irregularities. The research consists of three phases; i) regular buildings designed after 1975, ii) regular buildings designed prior to 1975, and iii) irregular buildings designed prior to 1975. The latter two phases address older buildings prior to the development of modern seismic building codes. All three phases were carried out by selecting and designing buildings in Ottawa, representing the seismic region in eastern Canada, as well as buildings in Vancouver, representing the seismic region in western Canada. Buildings had three heights (2; 5; and 10-stories) to cover a wide range of building periods encountered in practice. The resulting fragility curves indicated that the older buildings showed higher probabilities of exceeding life safety and/or collapse prevention performance levels. Newer buildings showed higher probabilities of exceeding target performance levels in western Canada than those located in the east.
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Failed States in International Relations / Zhroucené státy v mezinárodních vztazíchČepilová, Barbora January 2009 (has links)
The aim of the work Failed States in International Relations is the examination of this phenomenon regarding the terminological discrepancy, causes of the state fragility, security and social aspects and the various attitudes from the side of the international communities. A special part is dealing with so called "successfully failed states" where despite the obvious non-functioning the state is able to survive due to the revenues from the natural resources. The ?ndings are represented on the case study of the Democratic Republic of the Congo - a country with huge potential but miserable performance by now.
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Rethinking risk management practices in light of the Icelandic financial crisis / Rethinking risk management practices in light of the Icelandic financial crisisStárek, Václav January 2012 (has links)
Foremost, the thesis aims at mapping and analysing several aspects of the Icelandic financial crisis relevant to the practice of risk management, particularly with respect to banking sector. It identifies six possible sources of vulnerability occurring in the pre-crisis period. The domestic banking sector along with the entire Iceland's economy was pressurised by these stressors, which gradually led to the meltdown. The second chapter opens a discussion about the nature and characteristics of uncertainty and risk. It further strives to classify both the degrees of uncertainty and the elements of business and financial risks. The final chapter probes into the trickiness of dependence and expectations (in statistical sense of these terms), especially examining the limitations imposed on linear correlation as well as the violation of the assumptions underlying historical Value-at-risk and Expected shortfall approaches to estimating market risk.
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Efficient Computation of Accurate Seismic Fragility Functions Through Strategic Statistical SelectionFrancisco J. Pena (5930132) 15 May 2019 (has links)
A fragility function quantifies the probability that a structural system reaches an undesirable limit state, conditioned on the occurrence of a hazard of prescribed intensity level. Multiple sources of uncertainty are present when estimating fragility functions, e.g., record-to-record variation, uncertain material and geometric properties, model assumptions, adopted methodologies, and scarce data to characterize the hazard. Advances in the last decades have provided considerable research about parameter selection, hazard characteristics and multiple methodology for the computation of these functions. However, there is no clear path on the type of methodologies and data to ensure that accurate fragility functions can be computed in an efficient manner. Fragility functions are influenced by the selection of a methodology and the data to be analyzed. Each selection may lead to different levels of accuracy, due to either increased potential for bias or the rate of convergence of the fragility functions as more data is used. To overcome this difficulty, it is necessary to evaluate the level of agreement between different statistical models and the available data as well as to exploit the information provided by each piece of available data. By doing this, it is possible to accomplish more accurate fragility functions with less uncertainty while enabling faster and widespread analysis. In this dissertation, two methodologies are developed to address the aforementioned challenges. The first methodology provides a way to quantify uncertainty and perform statistical model selection to compute seismic fragility functions. This outcome is achieved by implementing a hierarchical Bayesian inference framework in conjunction with a sequential Monte Carlo technique. Using a finite amount of simulations, the stochastic map between the hazard level and the structural response is constructed using Bayesian inference. The Bayesian approach allows for the quantification of the epistemic uncertainty induced by the limited number of simulations. The most probable model is then selected using Bayesian model selection and validated through multiple metrics such as the Kolmogorov-Smirnov test. The subsequent methodology proposes a sequential selection strategy to choose the earthquake with characteristics that yield the largest reduction in uncertainty. Sequentially, the quantification of uncertainty is exploited to consecutively select the ground motion simulations that expedite learning and provides unbiased fragility functions with fewer simulations. Lastly, some examples of practices during the computation of fragility functions that results i n undesirable bias in the results are discussed. The methodologies are implemented on a widely studied twenty-story steel nonlinear benchmark building model and employ a set of realistic synthetic ground motions obtained from earthquake scenarios in California. Further analysis of this case study demonstrates the superior performance when using a lognormal probability distribution compared to other models considered. It is concluded by demonstrating that the methodologies developed in this dissertation can yield lower levels of uncertainty than traditional sampling techniques using the same number of simulations. The methodologies developed in this dissertation enable reliable and efficient structural assessment, by means of fragility functions, for civil infrastructure, especially for time-critical applications such as post-disaster evaluation. Additionally, this research empowers implementation by being transferable, facilitating such analysis at community level and for other critical infrastructure systems (e.g., transportation, communication, energy, water, security) and their interdependencies.
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Vieillissements pluriels : Expériences des "parents" âgés Sénégalais en cours de fragilisation / MULTIPLE AGING : Experiences of aging Senegalese "parents" being weakenedNiyonsaba, Emmanuel 26 November 2018 (has links)
Cette thèse s’inscrit dans une analyse des dynamiques contemporaines du vieillissement dans les sociétés africaines, particulièrement au Sénégal. Elle propose d’explorer les expériences des « parents » âgés en cours de fragilisation à travers le prisme de la solidarité face au changement social, de saisir les ambivalences relatives, d’une part à leur place au sein de la sphère familiale et sociale, et d’autre part dans les représentations de la vieillesse. Cette recherche déconstruit tout d’abord les représentations de la vieillesse en montrant que les « parents » âgés ne sont pas de « simples assistés », mais des acteurs au sein du réseau familial de solidarité et que « leurs vieillissements » sont pluriels, dynamiques et riches d’inventivité. Ensuite, à partir des enquêtes qualitatives réalisées au Sénégal et de façon complémentaire auprès de migrants sénégalais en France (le Havre), la recherche met en lumière les limites des solidarités familiales dans l’accompagnement social des « parents » âgés et appelle à l’imagination de solutions variées envers les personnes vieillissantes. Enfin, les transformations dans les modalités d’exercice des solidarités familiales envers les personnes âgées invitent à un retournement de regard, sinon de paradigme dominant, dans la façon de penser la vieillesse. Cette thèse est une contribution à la connaissance des expériences multiples du vieillissement. / This thesis is part of an analysis of the contemporary dynamics of aging in African societies, particularly in Senegal. It proposes to explore the experiences of elderly "parents" in the process of becoming fragile through the prism of solidarity in a context of social change, to grasp the relative ambivalences, on the one hand in their place within the family and social sphere, and on the other hand in the representations of aging. This research deconstructs first of all the representation of aging by showing that the elderly parents are not the "simple assisted", but actors within the family solidarity and that "their ageing" are plural, dynamic and rich of inventiveness. Then, from the qualitative surveys carried out in Senegal and in a complementary way with Senegalese migrants living in France (Le Havre), the research highlights the limits of family solidarities in the social accompaniment of elderly "parents" and calls for imagining of varied solutions to ageing people. Finally, the transformations in the family modalities of exercising of solidarities towards the elderly invite to a reversal of glance, if not dominant paradigm, in the way of thinking old age. This thesis is a contribution to the knowledge of the multiple experiences of aging.
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Climate security risks and resilience: Challenges and approaches for resilience building in fragile contextsLindström, Kristen January 2021 (has links)
The intersection of climate change and fragility is a critical focal point if the aspirations of the 2030 Sustainable Development Goals (SDG) are to be met. Climate-related security risks arise when the impacts from climate change overlap with societal vulnerabilities to expose and compound risks to human security. When national governments are unable or unwilling to adequately address these compound risks, communities are left to fend for themselves. A resilience-based approach has been proven to strengthen social-ecological systems in the face of shocks and stresses, but how does an established resilience agenda apply in fragile social-ecological systems? What is important for building resilience in fragile contexts that face the most severe realities of climate change against a backdrop of instability? This thesis addresses these questions with semi-structured qualitative interviews from experts working across scales in peacebuilding and development who work in some of the most challenging contexts on the planet. Results show that flexibility in livelihoods, social organization, a holistic or systems thinking approach and supporting traditional and cultural forms of resilience are beneficial in fragile contexts. While some of these resilience indicators are well-established, others are in need of further exploration. This study provides a glimpse into how the fields of resilience thinking and peace and conflict studies are joining up in order to address the new global risk landscape of the Anthropocene.
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Storm Surge Risk Assessment and of Levee SystemsRahimi, Mehrzad January 2021 (has links)
No description available.
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Correlating Melt Dynamics with Topological Phases of Homogeneous Chalcogenide- and Modified Oxide- Glasses Using Raman Scattering, Infra-Red Spectroscopy, Modulated-Differential Scanning Calorimetry and Volumetric ExperimentsChbeir, Ralph January 2019 (has links)
No description available.
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Seismic experimental analyses and surrogate models of multi-component systems in special-risk industrial facilitiesNardin, Chiara 22 December 2022 (has links)
Nowadays, earthquakes are one of the most catastrophic natural events that have a significant human, socio-economic and environmental impact. Besides, based on both observations of damage following recent major/moderate seismic events and numerical/experimental studies, it clearly emerges that critical non-structural components (NSCs) that are ubiquitous to most industrial facilities are particularly and even disproportionately vulnerable to those events.
Nonetheless and despite their great importance, seismic provisions for industrial facilities and their process equipment are still based on the classical load-and-resistance factor design (LRFD) approach; a performance-based earthquake engineering (PBEE) approach should, instead, be preferred. Along this vein, in recent years, much research has been devoted to setting computational fragility frameworks for special-risk industrial components and structures.
However, within a PBEE perspective, studies have clearly remarked: i) a lack of definition of performance objectives for NSCs; ii) the need for fully comprehensive testing campaigns data on coupling effects between main structures and NSCs. In this respect, this doctorate thesis introduces a computational framework for an efficient and accurate seismic state-dependent fragility analysis; it is based on a combination of data acquired from an extensive experimental shake table test campaign on a full-scale prototype industrial steel frame structure and the most recent surrogate-based UQ forward analysis advancements. Specifically, the framework is applied to a real-world application consisting of seismic shake table tests of a representative industrial multi-storey frame structure equipped with complex process components, carried out at the EUCENTRE facility in Italy, within the European SPIF project: Seismic Performance of Multi-Component Systems in Special Risk Industrial Facilities. The results of this experimental research campaign also aspire to improve the understanding of these complex systems and improve the knowledge of FE modelling techniques. The main goals aim to reduce the huge computational burden and to assess, as well, when the importance of coupling effects between NSCs and the main structure comes into play. Insights provided by innovative monitoring systems were then deployed to develop and validate numerical and analytical models. At the same time, the adoption of Der Kiureghian's stochastic site-based ground motion model (GMM) was deemed necessary to severely excite the process equipment and supplement the scarcity of real records with a specific frequency content capable of enhancing coupling effects. Finally, to assess the seismic risk of NSCs of those special facilities, this thesis introduces state-dependent fragility curves that consider the accumulation of damage effects due to sequential seismic events. To this end, the computational burden was alleviated by adopting polynomial chaos expansion (PCE) surrogate models. More precisely, the dimensionality of a seismic input random vector has been reduced by performing the principal component analysis (PCA) on the experimental realizations. Successively, by bootstrapping on the experimental design, separate PCE coefficients have been determined, yielding a full response sample at each point. Eventually, empirical state-dependent fragility curves were derived.
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