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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.
361

Does the concept of 'resilience' offer new insights for effective policy-making? : an analysis of its feasibility and practicability for flood risk management in the UK

Gao, Shen January 2018 (has links)
The concept of resilience is increasingly applied to policy-making. However, despite its widespread use, resilience remains poorly defined, open to multiple interpretations, and challenging to translate into practical policy instruments. Three particularly problematic aspects of resilience concern its rigid conceptualisation of adaptation and learning, its de-politicised interpretation of participatory decision-making, and the ill-defined role and relevance of social vulnerability indicators. My research analyses these three aspects within the context of flood risk management in the UK, which is uniquely suited to studying the practicability of a cross-disciplinary concept like resilience, because it connects issues of natural resource management, social planning, and disaster management. First, I analyse two case studies of experimental pilot projects in natural flood management. Through studying project reports, and interviewing stakeholders involved in project implementation, I determine whether the theorised learning-by-doing method in resilience is reflected in experiences from real experimental projects. Secondly, I use one of these case studies to map out the political structure of local participatory bodies in flood management, and also conduct a small survey of local community groups. The purpose of this second study is to determine if collaborative methods can indeed lead to a knowledge-driven policy process as envisioned in resilience literature. Lastly, I use statistical analysis to compare a traditional flood management model and a socio-economic model. The aim of the statistical modelling is to determine whether socio-economic factors are indeed useful for informing flooding policy, and whether they offer new insights not already being used in modern flood management. I find that resilience gives insufficient consideration to the importance of political constraints and economic trade-offs in policy-making, and that evidence for the usefulness of socio-economic factors is inconclusive. Future work could focus on further refining the statistical modelling to pinpoint empirically verifiable indicators of resilience.
362

Sensitivity of Hazus-MH Flood Loss Estimates to Selection of Building Parameters: Two Illinois Case Studies

Shrestha, Samir 01 December 2014 (has links)
In this study, Hazus-MH (v 2.1 SP 2) flood-loss estimation tools were assessed for their sensitivity to an array of different building and model parameters. The purpose of this study is to help guide users of the Hazus-MH flood-loss modeling tool in the selection of most appropriate model parameters. Six model parameters (square footage of the building, building age, construction types, foundation types, first floor heights, and the number of stories in the building) were assessed for their impacts on flood losses using the Hazus-MH user defined and aggregate flood-loss models. Building stock databases for these analyses were developed using county assessor records from two Illinois counties. A validation assessment was also performed using observed flood-damage survey data collected after the 2011 Mississippi River Flood which inundated the Olive Branch Area in Alexander County, Illinois. This analysis was performed to assess the accuracy of the detailed Hazus-MH User Defined Facility (UDF) flood-loss modeling tool. The foundation types and its associated first floor heights and number of stories in the building were found to substantially impact flood-loss estimates using the Hazus-MH flood-loss modeling tool. The model building parameters square footage, building age and construction type had little or no effect on the flood-loss estimates. The validation assessment reveled Hazus-MH UDF flood-loss modeling tool is capable of providing a reasonable estimate of actual flood losses. The validation assessment showed the modeled results to be within 23% of actual losses. The validation study results attained in this study using the detailed UDF flood-loss modeling tool where more realistic (within 23% of actual losses versus > 50% of actual losses) than previous Hazus-MH flood-loss validation assessments. The flood-loss estimates could be further improved by modifying or choosing a more region specific depth-damage curve, using higher resolution DEM and improving the flood-depth grid by incorporating more detailed flood elevation data or estimates using detailed hydraulic models that better reflects the local inundation conditions.
363

RESPONSE TO FLOOD HAZARDS: ASSESSING COMMUNITY FACTORS THAT AFFECT THE DECISION TO RELOCATE

VanPelt, Alex Jacob 01 May 2013 (has links)
Flooding in the United States has been increasing over the past century due to changing hydrological conditions as well as increased human manipulation of the waterways. People continue to live in these high hazard areas, even with increasing risk levels. Flood hazard mitigation has increasingly become a primary goal of floodplain managers with buyouts, insurance, and other nonstructural approaches becoming more prevalent over the past two decades. Whole town relocations have become one flood mitigation option. This study explores which community factors affect a town's decision to relocate. Three study areas in the Midwestern U.S. were analyzed: Valmeyer, IL, Rhineland, MO, and Pattonsburg, MO. Each of these three towns underwent a buyout and town relocation after the flood of 1993. Data was gathered using personal interviews with community members, specifically elected officials and relocation committee members. Analysis of interview responses identified community sense of place as the primary factor influencing relocation decisions including leadership, cost, people, and landscape. Leadership included town incorporation, relocation decision and committees, handling of legal issues, and site selection criteria. Cost involved the relocation cost, post-disaster development and tourism, and the business community of the study areas. People included the town heritage, community type, and the various community organizations. Landscape includes the types of relocation completed, the speed of the relocation event, and the amount of pre-disaster planning. Maps created show the pre and post-relocation municipal boundary of the study sites in relation to the 500-year floodplain boundary.
364

USING HAZUS-MH TO CALCULATE EXPECTED ANNUAL DAMAGE FOR FLOODPLAIN-MANAGEMENT SCENARIOS ALONG THE MIDDLE MISSISSIPPI RIVER

Dierauer, Jennifer Renee 01 May 2011 (has links)
This study combined flood-frequency analysis, 1-D (one-dimensional) hydraulic modeling using HEC-RAS, and flood-loss modeling using FEMA's Hazus-MH (Hazards U.S. Multi-Hazard) in order to: 1) quantify how different flood-frequency methodologies affect flood-risk assessments, and 2) quantify the impacts of different floodplain-management scenarios along the Middle Mississippi River (MMR). The nine scenarios tested here included various combinations of flood-frequency methodology, buyouts, and levee configurations. The levee configurations analyzed included: 1) current levee configuration, 2) no levees, 3) a 1500 m levee setback, 4) a 1000 m levee setback, and 5) a customized levee setback designed to maximize protection around existing infrastructure. Two study reaches were chosen: (1) an Urban Study Reach within St. Clair and northern Monroe Counties, IL, with levees designed to withstand the 500-year flood and (2) an Agricultural Study Reach within Union and Jackson Counties, IL, with <100-year levees. A flood-frequency analysis was completed for the St. Louis, MO gauging station, and detailed building inventories were used to estimate flood losses on a structure-by-structure basis (Hazus-MH UDF analysis) for an array of floods ranging from the 2- to the 500-year events. These flood-loss estimates were combined with a stochastic levee-failure model. Finally, estimated flood damages from Hazus-MH were integrated across the full range of flood recurrences in order to calculate expected annual damage (EAD). This study's flood-frequency analysis and corresponding flood-loss assessment demonstrate how differences in flood-frequency methodology can significantly impact flood-risk assessments. EAD based on the UMRSFFS (Upper Mississippi River System Flow Frequency Study) flood frequencies was 68% ($45.4 million) lower than EAD based on this study's flood frequencies. This decrease in EAD demonstrates that the UMRSFFS flood frequencies and corresponding stages may significantly underestimate flood risk within the Urban Study Reach. The 100-year discharge in the UMRSFFS appears to be underestimated by an estimated 17% (187,000 cfs), resulting in a 10% (1.6 m) underestimation of the 100-year flood level. Given the magnitude of the EAD, discharge, and stage differences documented here, a reanalysis of the MMR flood frequencies, flood profiles, and flood maps should be considered. The hydraulic modeling completed here showed that levee setbacks and levee removal successfully reduce stages for all recurrence intervals. For the 100-year flood, average reductions ranged from 0.20 m for a 1000 m levee setback to 1.61 m with levees removed. In general, stage reductions increased with increasing discharge and with increasing setback distance. The flood-level reductions are attributed to increased floodwater storage and conveyance across the reconnected floodplain. Compared to the current conditions, the levee setback and levee removal scenarios tested here reduced flood losses for large, infrequent flooding events but increased flood losses for smaller, more frequent flood events. When combined with buyouts of unprotected structures, levee setbacks reduced flood losses for all recurrence intervals. The 1000 m and 1500 m levee setbacks required buyouts in order to reduce EAD; however, a levee setback carefully planned around existing high-value structures reduced EAD with or without buyouts. The planned levee setback configuration combined with buyouts resulted in the largest decreases in EAD: a $16.8 million (55%) decrease in the Urban Study Reach and an $8.3 million (93%) decrease in the Agricultural Study Reach. Overall, this project showed that levee setbacks in combination with buyouts are an economically viable approach for flood-risk reduction along the study reaches and likely elsewhere where levees are widely employed for flood control. Designing a levee setback around existing high-value infrastructure can maximize the benefit of the setback while simultaneously minimizing the costs. Potentially, this type of planned levee configuration could be used as a template for the replacement of aging or failing levee systems.
365

Evaluating the Sensitivity of Cross Section Positioning when Computing Peak Flow Discharge using the Slope-Area Computation in a Mountain Stream

Forbes, Brandon Tracy, Forbes, Brandon Tracy January 2016 (has links)
The slope-area method is a commonly used and widely accepted technique for estimating peak flood flows in rivers where direct discharge measurements could not be obtained during the flood. The method makes multiple assumptions to simplify calculations which include assuming uniform flow conditions between surveyed cross sections, and that losses of energy in the reach occur only due to bank friction. Even though flows in nature do not always exhibit these simplified conditions, this method has been proven to provide adequate results when compared to direct measurements and thus, has become the go-to approach. To conduct a slope-area computation, the hydrologist needs to make multiple assumptions in the field based on experience, judgment, and published resources as guides. One of these assumptions is determining where to locate cross sections for the slope-area computation such that they sufficiently represent the cross-sectional area and slope of the channel. Traditional methods suggest to place the cross sections at breaks in the water surface slope. This research focuses on the variability of results of computed discharge values when cross sections are located at many different locations in the reach. What has been found is that many combinations of cross sections in the reach, including sections not located at the breaks in water surface slope, produce similar results when compared to the traditional methods. In fact, 121 of these combinations of cross sections produce peak discharge calculations within plus or minus five percent of the traditional methodology. What also was found was that variability in channel geometry goes unnoticed when using the traditional locating method, and losses due to expansion and contraction of flow area at locations which would not have been traditionally surveyed are occurring at multiple cross sections in the reach. The results suggest that reaches be evaluated for changes in geometry and not overlooked, so that the changes in shape, and subsequent losses in energy, be considered in the computation.
366

Právní režim pozemků spojených s vodami / Legal regime of water related land

Zemko, Peter January 2015 (has links)
The introduced graduation theses deals with the issue of legal regime of land associated with water. In the four major fields, which are water courses, land relations in area protection of water, land relations in areas endangered with high flood and land relations connected to waterworks, the theses analyses legal regulations of land relations with the emphasis on limitations of ownership, which conclude from these relations. In the center of attention of the theses are the laws in the water act, laws which are inferior to the legal force of the water act and laws in the new civil code.
367

Likelihood development for a probabilistic flash flood forecasting model

Keefer, Timothy Orrin, Keefer, Timothy Orrin January 1993 (has links)
An empirical method is developed for constructing likelihood functions required in a Bayesian probabilistic flash flood forecasting model using data on objective quantitative precipitation forecasts and their verification. Likelihoods based on categorical and probabilistic forecast information for several forecast periods, seasons, and locations are shown and compared. Data record length, forecast information type and magnitude, grid area, and discretized interval size are shown to affect probabilistic differentiation of amounts of potential rainfall. Use of these likelihoods in Bayes' Theorem to update prior probability distributions of potential rainfall, based on preliminary data, to posterior probability distributions, reflecting the latest forecast information, demonstrates that an abbreviated version of the flash flood forecasting methodology is currently practicable. For this application, likelihoods based on the categorical forecast are indicated. Apart from flash flood forecasting, it is shown that likelihoods can provide detailed insight into the value of information contained in particular forecast products.
368

Fitting extreme value distributions to the Zambezi river flood water levels recorded at Katima Mulilo in Namibia

Kamwi, Innocent Silibelo January 2005 (has links)
Magister Scientiae - MSc / The aim of this research project was to estimate parameters for the distribution of annual maximum flood levels for the Zambezi River at Katima Mulilo. The estimation of parameters was done by using the maximum likelihood method. The study aimed to explore data of the Zambezi's annual maximum flood heights at Katima Mulilo by means of fitting the Gumbel, Weibull and the generalized extreme value distributions and evaluated their goodness of fit. / South Africa
369

Life Cycle of Deccan Trap Magma Chambers: A Crystal Scale Elemental and Strontium Isotopic Investigation

Borges, Melroy R 07 November 2007 (has links)
The Deccan Trap basalts are the remnants of a massive series of lava flows that erupted at the K/T boundary and covered 1-2 million km2 of west-central India. This eruptive event is of global interest because of its possible link to the major mass extinction event, and there is much debate about the duration of this massive volcanic event. In contrast to isotopic or paleomagnetic dating methods, I explore an alternative approach to determine the lifecycle of the magma chambers that supplied the lavas, and extend the concept to obtain a tighter constraint on Deccan’s duration. My method relies on extracting time information from elemental and isotopic diffusion across zone boundary in an individual crystal. I determined elemental and Sr-isotopic variations across abnormally large (2-5 cm) plagioclase crystals from the Thalghat and Kashele “Giant Plagioclase Basalts” from the lowermost Jawhar and Igatpuri Formations respectively in the thickest Western Ghats section near Mumbai. I also obtained bulk rock major, trace and rare earth element chemistry of each lava flow from the two formations. Thalghat flows contain only 12% zoned crystals, with 87Sr/86Sr ratios of 0.7096 in the core and 0.7106 in the rim, separated by a sharp boundary. In contrast, all Kashele crystals have a wider range of 87Sr/86Sr values, with multiple zones. Geochemical modeling of the data suggests that the two types of crystals grew in distinct magmatic environments. Modeling intracrystalline diffusive equilibration between the core and rim of Thalghat crystals led me to obtain a crystal growth rate of 2.03x10-10 cm/s and a residence time of 780 years for the crystals in the magma chamber(s). Employing some assumptions based on field and geochronologic evidence, I extrapolated this residence time to the entire Western Ghats and obtained an estimate of 25,000 – 35,000 years for the duration of Western Ghats volcanism. This gave an eruptive rate of 30 – 40 km3/yr, which is much higher than any presently erupting volcano. This result will remain speculative until a similarly detailed analytical-modeling study is performed for the rest of the Western Ghats formations.
370

Úloha veřejných financí a (proti)povodňová opatření / The Role of Government (Public Finance) and (anti) flood measures

Bílková, Dagmar January 2010 (has links)
The object of the thesis The Role of Government (Public Finance) and (anti) flood measures is an introduction into the theory of public finance and problems of natural disasters whose following solution or redevelopment can cause involvement of public sources. We pay the attention to protection from floods from floods and its efficiency, social responsibility for liquidation of damages and the role of private insurance. The output of the work is the refutation of efficiency of funds spent in a particular cause -- on anti flood measures which are funded from the program of Ministry of Agriculture 129 120 Support of Flood Prevention II, and assessment of flood efforts and the role of government during the reconstruction of the area.

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