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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.
371

Alban Berg as Liedkomponist: An Analytical Study of his Two Settings of "Schliesse mir die Augen beide," 1907 and 1925

Ray, Karen, 1951- 05 1900 (has links)
Alan Berg's two musical settings of Theodor Storm's poem"Schliesse mir die Augen beide" have received little in the way of scholarly analytical attention. The three major chapters of this thesis deal with the two settings on three different levels. Chapter II surveys the political and cultural milieu in which Berg functioned as a young composer of Lieder in the years 1900-1910. Chapter III examines the special quality of lyricism which is often attributed to Berg and his works. Chapter IV provides more definitive and complete musical analyses of the two settings than have heretofore been available. The question of what role songwriting played in the development of Berg's compositional process is addressed in the conclusion.
372

Microfacies Analysis, Sedimentary Petrology, and Reservoir Characterization of the Sinbad Limestone Based Upon Surface Exposures in the San Rafael Swell, Utah

Osborn, Caleb R. 16 July 2007 (has links) (PDF)
The Lower Triassic Sinbad Limestone Member of the Moenkopi Formation has produced minor amounts of oil in the Grassy Trail Creek field near Green River, Utah and is present below much of central Utah including the recently discovered Covenant field. Superb outcrops of this thin (15 m), mixed carbonate-silicilastic unit in the San Rafael Swell permit detailed analysis of its vertical and lateral reservoir heterogeneity. Vertically, the Sinbad Limestone comprises three facies associations: (A) a basal storm-dominated, well-circulated skeletal-oolitic-peloidal limestone association, (B) a storm-dominated, poorly-circulated hummocky cross-stratified siliciclastic/peloidal association, and (C) a capping peritidal cross-bedded oolitic dolograinstone association. Eleven microfacies are present in 14 measured sections within the Sinbad Limestone. Lateral variation is most pronounced in the upper part of the basal limestone where storm-deposited beds pinch out over a lateral distance of one kilometer. Otherwise, individual beds and microfacies display a large degree of lateral homogeneity and regional persistence. Diagenesis is strongly controlled by microfacies. Diagenetic elements include marine fibrous calcite cements, micritized grains, compaction, dissolution and neomorphism of aragonite grains, meteoric cements, pressure dissolution, and dolomitization. The paragenetic sequence progresses from marine to meteoric to burial. Marine and meteoric cements occlude much of the depositional porosity. Hydrocarbon-lined interparticle and separate vug (largely molds) pores (1-5%) characterize the skeletal-oolitic limestones with permeability ranging from 0-100 md. Low permeability/porosity characterizes the middle silicilastic unit. The best reservoir qualities (permeability 400 md) occur in portions of the dolomitized oolitic grainstones that form the upper 2 to 3 m of the Sinbad Limestone. Fracture analysis of the studied area indicates a strong NW-SE trend. Fracture spacing is associated with lithology. Fracturing of limestone possibly displays a higher dependence upon bed thickness and microfacies type. The degree of dolomitization controls and increases fracture spacing while siltstones display more closely spaced fractures. The basal limestone unit is an oil storage unit, medial siltstones are flow baffles/barriers, and the dolostone caprock is an oil flow unit. If good connectivity through fractures can be obtained between the dolostone and limestone units, the Sinbad Limestone has potential to serve as a reservoir. This study will not only aid in future Sinbad exploration, but will serve as a model for parasequence-scale intervals in thicker mixed carbonate-siliciclastic successions.
373

Modeling the Effects of Winter Storms on Power Infrastructure Systems in the Northern United States

Pino, Jordan Vick 30 September 2019 (has links)
No description available.
374

Stormande kunskaper - en undersökning om år 6 elevers kunskaper kring begreppet storm

Andersson, Susanne, Carlsson, Johanna January 2007 (has links)
Syftet med vårt examensarbete är att undersöka om hur vissa elever i år 6 uttrycker sig kring frågor relaterade till begreppet storm. Kan de se dess orsak och verkan? Utifrån svaren ville vi även ta reda på om eleverna uppnår till de mål i geografi för det femte skolåret, som kan kopplas till väder, specifikt storm. Vi har använt oss av en kvalitativ metod som innebar djupintervjuer av elva stycken elever på en skola i Malmö. Resultatet visar att eleverna inte uppnår de mål som är kopplade till kursplanen i geografi för det femte skolåret, beträffande begreppet storm. Det visar sig att deras kunskap om begreppet storm i viss mån är obefintlig då de har svårt för att redogöra, förklara samt motivera svaren. Svaren eleverna gav grundar sig i egna erfarenheter samt upplevelser och kan inte knytas an till någon skolkunskap. / The aim whit our dissertaion is to examine some pupils in grade 6 how they express themeselfes concerning questions related to the conception Storm. Can they see it`s cause and effects? From the answers we also wanted to find out if the pupils achieve the goals in geograpy for the fifht schoolyear which can be related to weather,specificly storm. We used a method called qualitative interview´s which meant deepinterviews whit eleven pupils at a school in Malmö. The result showed that the pupils did not achieve the goals which are related to the curriculum in geography for the fifth year, concerning the conception Storm. It showed that their knowledege about the conception Storm to some extent is nonexistent,it also showed that they have a hard time to give an account for explain and motivate their answers. The answer`s the pupils gave is based on their own experience`s and can not be attached to any knowledge from school.
375

Optimization Of An Unstructured Finite Element Mesh For Tide And Storm Surge Modeling Applications In The Western North Atlantic Ocean

Kojima, Satoshi 01 January 2005 (has links)
Recently, a highly resolved, finite element mesh was developed for the purpose of performing hydrodynamic calculations in the Western North Atlantic Tidal (WNAT) model domain. The WNAT model domain consists of the Gulf of Mexico, the Caribbean Sea, and the entire portion of the North Atlantic Ocean found west of the 60° W meridian. This high resolution mesh (333K) employs 332,582 computational nodes and 647,018 triangular elements to provide approximately 1.0 to 25 km node spacing. In the previous work, the 333K mesh was applied in a Localized Truncation Error Analysis (LTEA) to produce nodal density requirements for the WNAT model domain. The goal of the work herein is to use these LTEA-based element sizing guidelines in order to obtain a more optimal finite element mesh for the WNAT model domain, where optimal refers to minimizing nodes (to enhance computational efficiency) while maintaining model accuracy, through an automated procedure. Initially, three finite element meshes are constructed: 95K, 60K, and 53K. The 95K mesh consists of 95,062 computational nodes and 182,941 triangular elements providing about 0.5 to 120 km node spacing. The 60K mesh contains 60,487 computational nodes and 108,987 triangular elements. It has roughly 0.5 to 185 km node spacing. The 53K mesh includes 52,774 computational nodes and 98,365 triangular elements. This is a particularly coarse mesh, consisting of approximately 0.5 to 160 km node spacing. It is important to note that these three finite element meshes were produced automatically, with each employing the bathymetry and coastline (of various levels of resolution) of the 333K mesh, thereby enabling progress towards an optimal finite element mesh. Tidal simulations are then performed for the WNAT model domain by solving the shallow water equations in a time marching manner for the deviation from mean sea level and depth-integrated velocities at each computational node of the different finite element meshes. In order to verify the model output and compare the performance of the various finite element mesh applications, historical tidal constituent data from 150 tidal stations located within the WNAT model domain are collected and examined. These historical harmonic data are applied in two types of comparative analyses to evaluate the accuracy of the simulation results. First, qualitative comparisons are based on visual sense by utilizing plots of resynthesized model output and historical tidal constituents. Second, quantitative comparisons are performed via a statistical analysis of the errors between model response and historical data. The latter method elicits average phase errors and goodness of average amplitude fits in terms of numerical values, thus providing a quantifiable way to present model error. The error analysis establishes the 53K finite element mesh as optimal when compared to the 333K, 95K, and 60K meshes. However, its required time step of less than ten seconds constrains its application. Therefore, the 53K mesh is manually edited to uphold accurate simulation results and to produce a more computationally efficient mesh, by increasing its time step, so that it can be applied to forecast tide and storm surge in the Western North Atlantic Ocean on a real-time basis.
376

The Effect Of Tidal Inlets On Open Coast Storm Surge Hydrographs: A Case Study Of Hurricane Ivan (2004)

Salisbury, Michael 01 January 2005 (has links)
Florida's Department of Transportation requires design storm tide hydrographs for coastal waters surrounding tidal inlets along the coast of Florida. These hydrographs are used as open ocean boundary conditions for local bridge scour models. At present, very little information is available on the effect that tidal inlets have on these open coast storm tide hydrographs. Furthermore, current modeling practice enforces a single design hydrograph along the open coast boundary for bridge scour models. This thesis expands on these concepts and provides a more fundamental understanding on both of these modeling areas. A numerical parameter study is undertaken to elucidate the influence of tidal inlets on open coast storm tide hydrographs. Four different inlet-bay configurations are developed based on a statistical analysis of existing tidal inlets along the Florida coast. The length and depth of the inlet are held constant in each configuration, but the widths are modified to include the following four inlet profiles: 1) average Florida inlet width; 2) 100 meter inlet width; 3) 500 meter inlet width; and 4) 1000 meter inlet width. In addition, two unique continental shelf profiles are used to design the ocean bathymetry in the model domains: a bathymetry profile consistent with the west/northeast coast of Florida (wide continental shelf width), and a bathymetry profile similar to the southeast coast of Florida (narrow continental shelf width). The four inlet-bay configurations are paired with each of the bathymetry profiles to arrive at eight model domains employed in this study. Results from these domains are compared to control cases that do not include any inlet-bay system in the computational domain. The ADCIRC-2DDI numerical code is used to obtain water surface elevations for all studies performed herein. The code is driven by astronomic tides at the open ocean boundary, and wind velocities and atmospheric pressure profiles over the surface of the computational domains. Model results clearly indicate that the four inlet-bay configurations do not have a significant impact on the open coast storm tide hydrographs. Furthermore, a spatial variance amongst the storm tide hydrographs is recognized for open coast boundary locations extending seaward from the mouth of the inlet. The results and conclusions presented herein have implications toward future bridge scour modeling efforts. In addition, a hindcast study of Hurricane Ivan in the vicinity of Escambia Bay along the Panhandle of Florida is performed to assess the findings of the numerical parameter study in a real-life scenario. Initially, emphasis is placed on domain scale by comparing model results with historical data for three computational domains: an ocean-based domain, a shelf-based domain, and an inlet-based domain. Results indicate that the ocean-based domain favorably simulates storm surge levels within the bay compared to the other model domains. Furthermore, the main conclusions from the numerical parameter study are verified in the hindcast study: 1) the Pensacola Pass-Escambia Bay system has a minimal effect on the open coast storm tide hydrographs; and 2) the open coast storm tide hydrographs exhibit spatial dependence along typical open coast boundary locations.
377

A High-resolution Storm Surge Model For The Pascagoula Region, Mississippi

Takahashi, Naeko 01 January 2008 (has links)
The city of Pascagoula and its coastal areas along the United States Gulf Coast have experienced many catastrophic hurricanes and were devastated by high storm surges caused by Hurricane Katrina (August 23 to 30, 2005). The National Hurricane Center reported high water marks exceeding 6 meters near the port of Pascagoula with a near 10-meter high water mark recorded near the Hurricane Katrina landfall location in Waveland, MS. Although the Pascagoula River is located 105 km east of the landfall location of Hurricane Katrina, the area was devastated by storm surge-induced inundation because of its low elevation. Building on a preliminary finite element mesh for the Pascagoula River, the work presented herein is aimed at incorporating the marsh areas lying adjacent to the Lower Pascagoula and Escatawpa Rivers for the purpose of simulating the inland inundation which occurred during Hurricane Katrina. ADCIRC-2DDI (ADvanced CIRCulation Model for Shelves, Coasts and Estuaries, Two-Dimensional Depth Integrated) is employed as the hydrodynamic circulation code. The simulations performed in this study apply high-resolution winds and pressures over the 7-day period associated with Hurricane Katrina. The high resolution of the meteorological inputs to the problem coupled with the highly detailed description of the adjacent inundation areas will provide an appropriate modeling tool for studying storm surge dynamics within the Pascagoula River. All simulation results discussed herein are directed towards providing for a full accounting of the hydrodynamics within the Pascagoula River in support of ongoing flood/river forecasting efforts. In order to better understand the hydrodynamics within the Pascagoula River when driven by an extreme storm surge event, the following tasks were completed as a part of this study: 1) Develop an inlet-based floodplain DEM (Digital Elevation Model) for the Pascagoula River. The model employs topography up to the 1.5-meter contour extracted from the Southern Louisiana Gulf Coast Mesh (SL15 Mesh) developed by the Federal Emergency Management Agency (FEMA). 2) Incorporate the inlet-based floodplain model into the Western North Atlantic Tidal (WNAT) model domain, which consists of the Gulf of Mexico, the Caribbean Sea, and the entire portion of the North Atlantic Ocean found west of the 60 degree West meridian, in order to more fully account for the storm surge dynamics occurring within the Pascagoula River. This large-scale modeling approach will utilize high-resolution wind and pressure fields associated with Hurricane Katrina, so that storm surge hydrographs (elevation variance) at the open-ocean boundary locations associated with the localized domain can be adequately obtained. 3) Understand the importance of the various meteorological forcings that are attributable to the storm surge dynamics that are setup within the Pascagoula River. Different implementations of the two model domains (large-scale, including the WNAT model domain; localized, with its focus concentrated solely on the Pascagoula River) will involve the application of tides, storm surge hydrographs and meteorological forcing (winds and pressures) in isolation (i.e., as the single forcing mechanism) and collectively (i.e., together in combination). The following conclusions are drawn from the research presented in this thesis: 1) Incorporating the marsh areas into the preliminary in-bank mesh provides for significant improvement in the astronomic tide simulation; 2) the large-scale modeling approach (i.e., the localized floodplain mesh incorporated into the WNAT model domain) is shown to be most adequate towards simulating storm surge dynamics within the Pascagoula River. Further, we demonstrate the utility of the large-scale model domain towards providing storm surge hydrographs for the open-ocean boundary of the localized domain. Only when the localized domain is forced with the storm surge hydrograph (generated by the large-scale model domain) does it most adequately capture the full behavior of the storm surge. Finally, we discover that while the floodplain description up to the 1.5-m contour greatly improves the model response by allowing for the overtopping of the river banks, a true recreation of the water levels caused by Hurricane Katrina will require a floodplain description up to the 5-m contour.
378

Model-Based Grid Modernization Economic Evaluation Framework

Onen, Ahmet 04 April 2014 (has links)
A smart grid cost/benefit analysis answers a series of economic questions that address the incremental benefits of each stage or decision point. Each stage of the economic analysis provides information about the incremental benefits of that stage with respect to the previous stage. With this approach stages that provide little or no economic benefits can be identified. In this study there are series of applications,-including quasi-steady state power flows over time-varying loads and costs of service, Monte Carlo simulations, reconfiguration for restoration, and coordinated control - that are used to evaluate the cost-benefits of a series of smart grid investments. In the electric power system planning process, engineers seek to identify the most cost-effective means of serving the load within reliability and power quality criteria. In order to accurately assess the cost of a given project, the feeder losses must be calculated. In the past, the feeder losses were estimated based upon the peak load and a calculated load factor for the year. The cost of these losses would then be calculated based upon an expected, fixed per-kWh generation cost. This dissertation presents a more accurate means of calculating the cost of losses, using hourly feeder load information and time-varying electric energy cost data. The work here attempts to quantify the improvement in high accuracy and presents an example where the economic evaluation of a planning project requires the more accurate loss calculation. Smart grid investments can also affect response to equipment failures where there are two types of responses to consider -blue-sky day and storm. Storm response and power restoration can be very expensive for electric utilities. The deployment of automated switches can benefit the utility by decreasing storm restoration hours. The automated switches also improve system reliably by decreasing customer interruption duration. In this dissertation a Monte Carlo simulation is used to mimic storm equipment failure events, followed by reconfiguration for restoration and power flow evaluations. The Monte Carlo simulation is driven by actual storm statistics taken from 89 different storms, where equipment failure rates are time varying. The customer outage status and durations are examined. Changes in reliability for the system with and without automated switching devices are investigated. Time varying coordinated control of Conservation Voltage Reduction (CVR) is implemented. The coordinated control runs in the control center and makes use of measurements from throughout the system to determine control settings that move the system toward optimum performance as the load varies. The coordinated control provides set points to local controllers. A major difference between the coordinated control and local control is the set points provided by the coordinated control are time varying. Reduction of energy and losses of coordinated control are compared with local control. Also eliminating low voltage problems with coordinated control are addressed. An overall economic study is implemented in the final stage of the work. A series of five evaluations of the economic benefits of smart grid automation investments are investigated. Here benefits that can be quantified in terms of dollar savings are considered here referred to as "hard dollar" benefits. Smart Grid investment evaluations to be considered include investments in improved efficiency, more cost effective use of existing system capacity with automated switches, and coordinated control of capacitor banks and voltage regulators. These Smart Grid evaluations are sequentially ordered, resulting in a series of incremental hard dollar benefits. Hard dollar benefits come from improved efficiency, delaying large capital equipment investments, shortened storm restoration times, and reduced customer energy use. The evaluation shows that when time varying loads are considered in the design, investments in automation can improve performance and significantly lower costs resulting in "hard dollar" savings. / Ph. D.
379

Natechs and Climate Change:Wide-scale Spatial Modeling of the Occurrence Probability and Variability of Tropical Storm-Related Natech Events in the United States Under Various Climate Scenarios / Natech災害と気候変動:多様な気候シナリオの下での米国における熱帯低気圧を引き金としたNatech事象の発生率と変動性に関する広範囲の空間モデリング

Xiaolong, Luo 23 March 2021 (has links)
京都大学 / 新制・課程博士 / 博士(工学) / 甲第23170号 / 工博第4814号 / 新制||工||1752(附属図書館) / 京都大学大学院工学研究科都市社会工学専攻 / (主査)教授 CRUZ Ana Maria , 教授 宇野 伸宏, 准教授 横松 宗太 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
380

Forecasting Storm Surge Risk and Optimization of Protective Measures

Dinenis, Philip Constantine Andreas January 2023 (has links)
Storm induced flooding presents a multifaceted threat to coastal communities across the world.With climate change and sea level rise this danger is expected to increase. As coastal communities become exposed to more frequent and more severe flooding, the need for protective measures will increase. To know how to optimally protect against coastal flooding requires an understanding of future flood risk, storms, and storm surge. These are challenging to estimate due to many sources of uncertainty. In this thesis I present a methodology to forecast this future flood risk. I combine multiple computational, physics and statistical models to accurately describe the fluid dynamics of flooding, the cyclones that drive surge, and how climate change will influence these different components in the future. These computational models must be fast so that they can be embedded into an optimization framework that makes many evaluations. To find an optimal protective measure I employ stochastic and derivative free optimization methods. A complete study is conducted on New York City and optimal protective strategies are found for minimizing the total cost from storm surge subject to different budget constraints.

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