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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
181

Beyond Mitigation: The Emotional Functions of Natural Disaster Folklore in Japan

Jania, Alexander Edward 01 September 2015 (has links)
No description available.
182

Development of Applicable Benchmark Experiments for (Th,Pu)O2 Power Reactor Designs Using TSUNAMI Analysis

Langton, Stephanie E. January 2013 (has links)
<p>When simulating reactor physics experiments, uncertainties in nuclear data result in a bias between simulated and experimental values. For new reactor designs or for power reactor designs the bias can be estimated using a set of experiments. How- ever, the experiments used to estimate the bias must be applicable to the power reactor design of interest. Similarity studies can be performed to ensure this is the case. Here, potential experiments in the ZED-2 heavy water critical facility at Chalk River Laboratories were developed that would be applicable to the multiplication factor bias calculation of three thoria plutonia fuelled power reactor designs. The power reactor designs that were analyzed were the CANDU 6 with 37-element fuel bundles and 43-element fuel bundles, and a Canadian SCWR design with 78- element fuel assemblies. The power reactors were simulated using the code package SCALE 6.1 under burnup conditions that were determined using the lattice code DRAGON 3.06H and the diffusion code DONJON 3.02A. The intermediate results from DRAGON and DONJON were used to compare the benefits of various reactor designs. Various critical core configurations were then simulated in the ZED-2 re- actor using the SCALE 6.1 package. The similarities between the potential ZED-2 reactor experiments and the power reactors were analyzed. These results were used to design a set of experiments having sufficiently high completeness that they can be used as part of a bias calculation using the generalized linear least squares method. To do so a methodology was developed to guide the experiment set design process in which the fuel type, lattice arrangements, and coolant type are modified and the effects on the sensitivity coverage analyzed. A set of six experiments was designed for which all of the power reactor designs had a completeness of 0.7 or higher.</p> / Master of Applied Science (MASc)
183

Foraminiferal taphonomy as a paleo-tsunami and overwash indicator in coastal environments - evidence from Oman and the British Virgin Islands

Pilarczyk, Jessica 04 1900 (has links)
Historical records suggest that the coastlines of the British Virgin Islands (BVI) and the Sultanate of Oman have been subjected to catastrophic storm and tsunami events throughout recorded history. In 1945, a 7.8 magnitude earthquake -100 km south of Karachi, Pakistan generated a tsunami that impacted the coast of Oman and resulted in over 4000 deaths. Although the 1945 tsunami deposit has been documented, no other paleo-tsunami deposits have been identified despite the fact that historical and paleo-seismic records suggest the contrary. Similarly, the north-eastern islands of the Caribbean, particularly Anegada, BVI, have been subjected to intense hurricane strikes over the past 300 years. Due to its position relative to the Atlantic Ocean and the Puerto Rico Trench, Anegada is a potential recorder of local (e.g. 1690, 1867) and trans-oceanic tsunami events (e.g. 1755 Lisbon) as well. Potential tsunami overwash events at both locations are expected to be intermingled with marine incursions resulting from major storms and Holocene sea level change. Discerning between storm and tsunami overwash is problematic and usually favours a storm interpretation due to their frequency in the geologic record. This bias and lack of properly constrained geologic evidence has hindered the accuracy of tsunami prediction models, and subsequently, the assessment of seismic and tsunami hazards at both locations. Several studies employ the use of foraminifera to distinguish between storm and tsunami deposition; however, they are traditionally conducted in contrasting settings where differences between the terrestrial and marine realms are easily detected. Marine influenced settings lack the same degree of contrast; therefore, microfossil analysis alone is not effective. This dissertation investigates the use of foraminiferal taphonomy as an overwash indicator in two types of coastal settings: 1. a silisiclastic arid system lagoon (Sur, Sultanate of Oman), and 2. semi-tropical carbonate marine ponds (Anegada, British Virgin Islands). Although traditional microfossil taphonomic characteristics have been reported in some overwash studies, no multi-variate investigation into their usefulness as tsunami or storm indicators has previously been conducted. This dissertation shows that the surface condition (e.g. angularity, color, size, fragmentation, etc.) of foraminifera provides important information regarding the origin of overwash deposits and is useful in detecting older deposits at both locations when combined with other proxies. Several important contributions have resulted from this research: 1. Taphofacies analysis helped to constrain sediment provenance and modern nearshore hydrodynamics in an arid system lagoon that could not be achieved with traditional foraminiferal analysis alone. 2. The combined use of foraminiferal provenance and taphonomy was effective in identifying the 1945 Makran Trench tsunami at Sur Lagoon and will be a good indicator of older events at this location; a point which is particularly significant since no geologic evidence of previous tsunami events has ever been recorded. High abundances of predominantly marine taxa coupled with high abundances of large test sizes, fragments and fossil specimens were found to be indicators of tsunami deposition in contrast to lagoon deposition which was characterized by smaller test sizes and less robust lagoon taxa. 3. The preservation of the reefal dwelling Homotrema rubrum, a common encrusting foraminifer in Caribbean reef settings, provided the direction of origin of an overwash event deposited in marine ponds at Anegada and constrained the list of potential overwash candidates. Large and highly preserved Homotrema fragments that are typical of modem reef and storm wrack sediment were found in high abundances within Sand and Shell Sheet in three marine ponds at Anegada. A decrease in the abundance of highly preserved specimens from north to south throughout the ponds, coupled with mollusc taphonomic data strengthens a tsunami interpretation for the deposit. This dissertation shows that taphofacies analysis has broad application to event stratigraphy in a variety of coastal systems. Although the application of taphonomic analysis between the two contrasting environments was widely different, in both cases, taphonomic data provided indicative information regarding the origin of deposition of overwash units at Anegada, BVI and Sur, Sultanate of Oman. / Thesis / Doctor of Philosophy (PhD)
184

Rapid Prediction of Tsunamis and Storm Surges Using Machine Learning

Lee, Michael 27 April 2021 (has links)
Tsunami and storm surge are two of the main destructive and costly natural hazards faced by coastal communities around the world. To enhance coastal resilience and to develop effective risk management strategies, accurate and efficient tsunami and storm surge prediction models are needed. However, existing physics-based numerical models have the disadvantage of being difficult to satisfy both accuracy and efficiency at the same time. In this dissertation, several surrogate models are developed using statistical and machine learning techniques that can rapidly predict a tsunami and storm surge without substantial loss of accuracy, with respect to high-fidelity physics-based models. First, a tsunami run-up response function (TRRF) model is developed that can rapidly predict a tsunami run-up distribution from earthquake fault parameters. This new surrogate modeling approach reduces the number of simulations required to build a surrogate model by separately modeling the leading order contribution and the residual part of the tsunami run-up distribution. Secondly, a TRRF-based inversion (TRRF-INV) model is developed that can infer a tsunami source and its impact from tsunami run-up records. Since this new tsunami inversion model is based on the TRRF model, it can perform a large number of tsunami forward simulations in tsunami inversion modeling, which is impossible with physics-based models. And lastly, a one-dimensional convolutional neural network combined with principal component analysis and k-means clustering (C1PKNet) model is developed that can rapidly predict the peak storm surge from tropical cyclone track time series. Because the C1PKNet model uses the tropical cyclone track time series, it has the advantage of being able to predict more diverse tropical cyclone scenarios than the existing surrogate models that rely on a tropical cyclone condition at one moment (usually at or near landfall). The surrogate models developed in this dissertation have the potential to save lives, mitigate coastal hazard damage, and promote resilient coastal communities. / Doctor of Philosophy / Tsunami and storm surge can cause extensive damage to coastal communities; to reduce this damage, accurate and fast computer models are needed that can predict the water level change caused by these coastal hazards. The problem is that existing physics-based computer models are either accurate but slow or less accurate but fast. In this dissertation, three new computer models are developed using statistical and machine learning techniques that can rapidly predict a tsunami and storm surge without substantial loss of accuracy compared to the accurate physics-based computer models. Three computer models are as follows: (1) A computer model that can rapidly predict the maximum ground elevation wetted by the tsunami along the coastline from earthquake information, (2) A computer model that can reversely predict a tsunami source and its impact from the observations of the maximum ground elevation wetted by the tsunami, (3) A computer model that can rapidly predict peak storm surges across a wide range of coastal areas from the tropical cyclone's track position over time. These new computer models have the potential to improve forecasting capabilities, advance understanding of historical tsunami and storm surge events, and lead to better preparedness plans for possible future tsunamis and storm surges.
185

Disaster Response, Peace and Conflict in Post-Tsunami Sri Lanka / Part 1: The Congestion of Humanitarian Space

Harris, S. January 2006 (has links)
Yes / ¿Part 1: The congestion of humanitarian space¿, assesses what affect the rapid proliferation of the international aid community¿s presence in Sri Lanka has had on local level relationships and emergency response capacities. It contends that the burgeoning presence of aid agencies resulted in humanitarian assistance becoming a hotly contested and competitive activity. It goes on to identify the possible factors that have contributed to the rapid congestion of this space in suggesting an explanation of why the humanitarian communities¿ normative standards appear to have failed.
186

Development of Fragility Curve Database for Multi-Hazard Performance Based Design

Tahir, Haseeb 14 July 2016 (has links)
There is a need to develop efficient multi-hazard performance based design (PBD) tools to analyze and optimize buildings at a preliminary stage of design. The first step was to develop a database and it is supported by five major contributions: 1) development of nomenclature of variables in PBD; 2) creation of mathematical model to fit data; 3) collection of data; 4) identification of gaps and methods for filling data in PBD; 5) screening of soil, foundation, structure, and envelope (SFSE) combinations.. A unified nomenclature was developed with the collaboration of a multi-disciplinary team to navigate through the PBD. A mathematical model for incremental dynamic analysis was developed to fit the existing data in the database in a manageable way. Three sets of data were collected to initialize the database: 1) responses of structures subjected to hazard; 2) fragility curves; 3) consequence functions. Fragility curves were critically analyzed to determine the source and the process of development of the curves, but structural analysis results and consequence functions were not critically analyzed due to lack of similarities between the data and background information respectively. Gaps in the data and the methods to fill them were identified to lay out the path for the completion of the database. A list of SFSE systems applicable to typical midrise office buildings was developed. Since the database did not have enough data to conduct PBD calculations, engineering judgement was used to screen SFSE combinations to identify the potential combinations for detailed analysis. Through these five contributions this thesis lays the foundation for the development of a database for multi- hazard PBD and identifies potential future work in this area. / Master of Science
187

Multi-Proxy Characterisation of the Storegga Tsunami and Its Impact on the Early Holocene Landscapes of the Southern North Sea

Gaffney, Vincent, Fitch, Simon, Bates, M., Ware, R.L., Kinnaird, T., Gearey, B., Hill, T., Telford, Richard, Batt, Catherine M., Stern, Ben, Whittaker, J., Davies, S., Ben Sharada, Mohammed, Everett, R., Cribdon, R., Kistler, L., Harris, Sam, Kearney, K., Walker, James, Muru, Merle, Hamilton, D., Law, M., Finlay, A., Bates, R., Allaby, R.G. 13 August 2020 (has links)
Yes / Doggerland was a landmass occupying an area currently covered by the North Sea until marine inundation took place during the mid-Holocene, ultimately separating the British landmass from the rest of Europe. The Storegga Event, which triggered a tsunami reflected in sediment deposits in the northern North Sea, northeast coastlines of the British Isles and across the North Atlantic, was a major event during this transgressive phase. The spatial extent of the Storegga tsunami however remains unconfirmed as, to date, no direct evidence for the event has been recovered from the southern North Sea. We present evidence of a tsunami deposit in the southern North Sea at the head of a palaeo-river system that has been identified using seismic survey. The evidence, based on lithostratigraphy, geochemical signatures, macro and microfossils and sedimentary ancient DNA (sedaDNA), supported by optical stimulated luminescence (OSL) and radiocarbon dating, suggests that these deposits were a result of the tsunami. Seismic identification of this stratum and analysis of adjacent cores showed diminished traces of the tsunami which was largely removed by subsequent erosional processes. Our results confirm previous modelling of the impact of the tsunami within this area of the southern North Sea, and also indicate that these effects were temporary, localized, and mitigated by the dense woodland and topography of the area. We conclude that clear physical remnants of the wave in these areas are likely to be restricted to now buried, palaeo-inland basins and incised river valley systems.
188

TF1 face au tsunami du 26 décembre 2004 : construction d’un objet politique et médiatique (déc.2004-fin 2009) / TF1 facing the December 26, 2004 tsunami : construction of a political and media-related object (Dec.2004-late 2009)

De Azevedo, Marlyce 05 February 2010 (has links)
Le 26 décembre 2004, l’un des plus violents séismes de l’histoire a lieu au large de l’île indonésienne de Sumatra, provoquant une série de tsunamis. Si les catastrophes naturelles constituent un type d’événement prisé des médias, celle-ci se distingue en tant que nouvel objet médiatique en mettant en œuvre, selon nous, une sémiotique de la crise fondée sur la confusion, la violence et l’urgence. Motivés par la concurrence et par le caractère inouï du tsunami, les médias ont proposé une information inscrite dans une logique de dramatisation, d’esthétique et de politique. Nous partons du postulat selon lequel la dramatisation s’est exprimée à travers : une couverture importante dans les semaines et les mois qui suivirent et la redondance d’images choquantes, la difficulté qu’ont éprouvé les médias à appréhender un phénomène étranger et le recours à une rhétorique de l’émotion basée sur une dialectique de l’éloignement et de la proximité. La représentation médiatique de l’événement met au jour les trois dimensions de celui-ci : une dimension réelle des conséquences humaines et matérielles de la catastrophe et des actions politiques qu’elle engendre, une dimension symbolique des interprétations auxquelles elle est sujette et des représentations qu’elle véhicule et une dimension imaginaire révélatrice des peurs liées aux catastrophes. De fait, la représentation révèle une vision du monde et de ses acteurs. Nous observerons comment la représentation s’articule à de nombreux questionnements : sur le lien entre catastrophe et écologie politique, entre catastrophe et risque et entre catastrophe et opposition Nord-Sud. Nous avons choisi, par ailleurs, de confronter notre corpus au domaine de la fiction, en nous appuyant sur un téléfilm anglo-américain : « Tsunami : les conséquences ». Ce parallèle permet de mettre en évidence la relation fiction-information, les particularités de la fiction et de l’information ainsi que l’identité politique, culturelle et idéologique de la chaîne. / On December 26, 2004 one of the most violent earthquakes in history hits offshore the Indonesian island of Sumatra, causing a series of tsunamis. If natural disasters represent a type of event valued by the media, this one distinguishes itself as a new media-related object, structured, according to us, on a crisis semiotic, based on confusion, violence and emergency. Motivated by competition and the unbelievable nature of the tsunami, the media offered an information in line with a logic of dramatization, aesthetic and politic. We take it as axiomatic that the dramatization expressed itself through: an important coverage during the weeks and months that followed and the redundancy of shocking images, the difficulty experienced by the media in the comprehension of an unfamiliar phenomenon and the use of a rhetoric of emotion based upon a dialectic of distance and proximity. The media representation of the event reveals its three dimensions: a reality dimension of the material and human consequences of the disaster and the political actions it generated, a symbolic dimension of the interpretations it is subject to and the representations it promotes and an imaginary dimension revealing the fears linked to disasters. De facto, the representation reveals a vision of the world and its actors. We mean to observe how the representation is based on many questioning: on the link between disaster and political ecology, disaster and risk, disaster and the North-South opposition. We also decided to confront our corpus to the area of fiction, by analyzing a British-American TV film: “Tsunami: the aftermath”. This parallel highlights the relation between information and fiction, the characteristics of fiction and information and the political, cultural and ideological identity of the TV channel.
189

Tsunami Hydrodynamics In Coastal Zones

Ozer, Ceren 01 June 2012 (has links) (PDF)
This study analyzes the parameter &ldquo / hydrodynamic demand&rdquo / that is also defined by the square of Froude Number representing the damage of tsunami waves on structures and coastlines, and other hydrodynamic parameters, i.e., the distribution of instantaneous flow depths, runup values and the direction of maximum currents, occurred during tsunami inundation by using advanced numerical modeling. The analyses are performed on regular-shaped basins with different bottom slopes and real-shaped topographies using different wave shapes, wave periods and types. Various orientation and amount of coastal and land structures are used in simulations to have results for many different cases. This study provides the opportunity to define the damage of level in residential areas and to test the performance of coastal protection structures. The behavior of tsunami hydrodynamic parameters in shallow and inundation zone is investigated and a correlation is obtained between the average maximum values of square of Froude Number with the wave characteristics and sea bottom slope. After determining hydrodynamic parameters in regular shaped basins, a case study is applied by modeling the March 11, 2011 Great East Japan Tsunami with finer resolution in nested domains. The determination of hydrodynamic parameters in inundation zone during 2011 Japan event is performed in one of the most damaged coastal city Kamaishi.
190

The Post-LGM Evolution of Milford Sound, Fiordland, New Zealand: Timing of Ice Retreat, the Role of Mass Wasting & Implications for Hazards

Dykstra, Jesse Leif January 2012 (has links)
The plate-boundary Alpine Fault runs immediately offshore of the popular tourist destination of Milford Sound, which is visited by more than half a million tourists each year. Glaciers retreated from the fiord between ~24-16 ka, leaving behind a legacy of extreme topography, including some of the world's highest sea cliffs, which tower nearly 2 km above the fiord. Visitors come to view the spectacularly steep and rugged landscape, with many cruising the fiord by boat. This project utilizes surface exposure dating (TCND) of glacially modified surfaces, to gain further insight into the glacier retreat history of Milford Sound. Exposure dates from strategic locations near the entrance to the fiord indicate that the main trunk glacier had retreated about 9 km from its peak LGM position by ~18 ka. Additional TCND and calibrated Schmidt Hammer data from a range of positions within the Milford catchment provide strong evidence that the main trunk glacier receded rapidly after about 18 ka, retreating a further 16 km to a position near the present-day confluence of the Tutoko and Cleddau rivers, by ~16 ka. Available seismic reflection data suggest that post-glacial sediment infill has been strongly influenced by massive deposits of rock avalanche debris. New high-resolution bathymetric and seismic reflection data reveals the presence of at least 18 very large post-glacial rock avalanche deposits which blanket ~40% of the fiord bottom. Geomorphic mapping and field investigation reveal the presence of at least ten additional very large to giant terrestrial landslide deposits in the lower Milford catchment; radiocarbon and surface exposure dating indicate that these events occurred during the Holocene, between ~9-1 ka. Ages of six of these deposits are in agreement with published rupture dates on the southern on-shore portion of the Alpine Fault.

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