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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.
171

Investigation of the California Undercurrent off the west coast of Vancouver Island

Krassovski, Maxim 14 August 2008 (has links)
Current meter records from a long term mooring site on the continental slope off the west coast of Vancouver Island, British Columbia, Canada are used to investigate the scales of variability of the subsurface California Undercurrent and its relation to possible driving mechanisms. Observed along the west coast of North America from Baja California to Vancouver Island, the California Undercurrent is part of the California Current System, a typical basin-scale eastern boundary circulation system. Of the four instruments at nominal depths of 35, 100, 175, and 400 m, the upper two show seasonally reversing flow, while the 175 m instrument registers a year-round poleward flow. The deepest current meter, located approximately 100 m above the bottom, reflects the influence of a nearby submarine canyon. The flow at 100 and 175 m depths, as well as the water properties sampled in the region with CTD casts, are characteristic of the temporal and spatial variability of the California Undercurrent over the continental slope off central and southern Vancouver Island. The correlation of the 175 m flow with local atmospheric forcing (wind stress) in the low-frequency band (periods of months) is higher than with ocean-wide climatic indices, suggesting that regional processes play a key role in the forcing of the subsurface flow.
172

PROTOCOLO DE AVALIAÇÃO RÁPIDA DE PARÂMETROS FÍSICOS INDICADORES DE EROSÃO EM TALUDES FLUVIAIS / RAPID ASSESSMENT PROTOCOL FOR PHYSICAL PARAMETERS INDICATORS OF EROSION IN RIVER SLOPES

Schettert, Teiva Fernanda 31 August 2015 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The development of rapid assessment protocols that work with indicators of erosion brittleness of river embankments, aims to relate parameters and provide diagnostics to assist in the management of water resources. Providing a new tool to be explored, with great possibility to be adopted as a method of practice and to generate reliable results. This research deals with the study of the Rapid Assessment Protocol (RAP) derived from the doctoral thesis "Indicators Brittleness Erosion in support of definition of Permanent Preservation Areas in rivers" of Josita Soares Monteiro, presented in 2014. The RAP consists of admittedly influential parameters on the stability of river embankments - vegetation; soil texture; stretch of the river; slope inclination; soil depth in slope; width of the stream and use and land cover - and of weights / notes concerning the characteristics of these parameters. As a result, the protocol provides a gradual classification concerning the state of "susceptibility to erosion" of the banks of the stream of Val Buia in Silveira Martins/RS, where this research was conducted. Amplification of the weight assigned to the parameters that make up the RAP of Monteiro (2014); performing a sensitivity analysis on RAP parameters in order to identify those that provide greater relevance in its final outcome; the implementation of changes in the criteria and structure of RAP and its reuse in the thesis study area, the stream Val Buia; and comparing the results of the original PAR with the PAR reapplied were the objectives of the study. The increase made on the weights of RAP parameters did not change the result of the classification of the sampling units in the categories of susceptibility to erosion. Sensitivity analysis demonstrated that the most sensitive parameters to changes in their weights are the highest scored, and, consequently, features which provide high susceptibility to erosion of the river embankments. The protocol used in the study area had partially similar result to that of Monteiro (2014). In order to better target the interpretations regarding the description of the area observed during visual assessment, it is suggested the preparation of well-defined characterization and typologies of measures for the RAP parameters evaluated. The addition of a new parameter in the protocol of Monteiro (2014) - the "river longitudinal profile" parameter - could provide better assessment of the areas that are affected by successive floods. Several fronts related to the assessment of the physical and environmental conditions of river embankments, such as environmental zoning, recovery projects of degraded areas and recovery of riparian forests may make use of the methodology proposed by RAP, as well as adding subsidies to the formulation and execution of natural engineering works aimed at stabilizing the banks of waterways. / O desenvolvimento de protocolos de avaliação rápida, que trabalham com indicadores de fragilidades à erosão de taludes fluviais, tem o objetivo de relacionar parâmetros e fornecer diagnósticos para auxiliar na gestão dos recursos hídricos. Constituindo uma nova ferramenta a ser explorada, com grande possibilidade de ser adotada como um método de utilização prática e geradora de resultados confiáveis. A presente pesquisa trata do estudo do Protocolo de Avaliação Rápida (PAR) oriundo da tese de doutorado Indicadores de Fragilidade à Erosão no apoio à definição de Áreas de Preservação Permanente em rios de Josita Soares Monteiro, apresentada em 2014. O referido PAR é constituído de parâmetros reconhecidamente influentes na estabilidade de taludes fluviais - vegetação; textura do solo; trecho do rio; inclinação do talude; profundidade do solo no talude; largura do curso d água e uso e cobertura da terra e de pesos/notas relativos ás características desses parâmetros. Como resultado, o protocolo apresenta uma classificação gradual com relação ao estado de suscetibilidade à erosão das margens do arroio Val de Buia em Silveira Martins/RS, no qual esta pesquisa foi realizada. A amplificação do peso atribuído aos parâmetros que compõem o PAR de Monteiro (2014); a realização de uma análise de sensibilidade sobre parâmetros do PAR com o propósito de identificar os que proporcionam maior relevância no seu resultado final; a implementação de mudanças nos critérios e estrutura do PAR; sua reaplicação na área de estudo da tese; e a comparação dos resultados do PAR original com o PAR reaplicado foram os objetivos do estudo. A ampliação realizada sobre os pesos dos parâmetros do PAR não alterou o resultado da classificação das unidades amostrais nas categorias de suscetibilidade à erosão. A análise de sensibilidade demonstrou que os parâmetros mais sensíveis às variações dos seus pesos são os de maior nota, e, consequentemente, características que conferem grande suscetibilidade a erosão dos taludes fluviais. O protocolo reaplicado na área de estudo apresentou resultado parcialmente semelhante ao de Monteiro (2014). Afim de melhor direcionar as interpretações quanto à descrição da área observada durante a avaliação visual, sugere-se a elaboração de caracterizações e tipologias de medidas bem definidas para os parâmetros avaliados no PAR. O acréscimo de um novo parâmetro no protocolo de Monteiro (2014) - o parâmetro trecho longitudinal - poderá proporcionar melhor avaliação das áreas que são acometidas por sucessivas inundações. Várias frentes relacionadas à avaliação das condições físico-ambientais dos taludes fluviais, tais como: zoneamentos ambientais, projetos de recuperação de áreas degradadas, de recuperação de matas ciliares poderão lançar mão da metodologia proposta pelo PAR, assim como acrescentar subsídios à formulação e execução de obras de engenharia natural direcionadas à estabilização das margens dos cursos d água.
173

Observância tributária: integrando paradigmas em busca de mais conformidade fiscal / Tax compliance: integrating paradigms seeking more tax compliance

Fabio Pereira da Silva 01 July 2015 (has links)
A pesquisa sobre observância tributária floresceu no campo econômico, tendo como estudos seminais as obras de Allingham e Sandmo (1972) e Srinivasan (1973). Esses artigos basearam-se na teoria de Becker (1968) sobre crime e punição, aceitando o paradigma econômico clássico, que parte do pressuposto de que os indivíduos adotam comportamentos racionais. Nas últimas décadas, contudo, muitos pesquisadores notaram que esse paradigma, do qual derivou aquilo que veio a ser chamado pela academia de \"paradigma do crime\", explicava apenas parcialmente o comportamento do contribuinte. Surge, então, toda uma linha de pesquisa contrapondo esse paradigma racional, partindo da constatação de que o comportamento do contribuinte é muito mais complexo do que inicialmente se supunha, merecendo uma análise multidisciplinar, ou seja, que não se restrinja ao campo econômico, mas que também abarque outras disciplinas. Esse novo paradigma foi denominado pela academia de \"paradigma do serviço\" que, em linhas gerais, contempla outros fatores envolvidos no ato de pagar tributos, inclusive psicológicos, pressupondo, de tal modo, que o contribuinte não é um indivíduo racional unicamente preocupado em maximizar sua utilidade, devendo ser visto pela administração pública como uma espécie de cliente, e recebendo tratamento adequado e serviços públicos de qualidade em contrapartida ao cumprimento de suas obrigações tributárias. O presente estudo faz uma apreciação dos dois paradigmas, introduzindo nessa avaliação conceitos da ciência denominada Análise do Comportamento, cujos ensinamentos sobre a aprendizagem e o comportamento humano têm o potencial de contribuir de forma significativa para o entendimento do assunto. Testando os pressupostos teóricos apresentados no decorrer do trabalho, foram realizados dois estudos empíricos, tomando-se como base o modelo criado pelo pesquisador e psicólogo Erich Kirchler, denominado Slippery Slope Framework, que confirma estudos anteriores e demonstra que tanto punições quanto recompensas são instrumentos eficazes no combate à evasão fiscal, sugerindo que a integração dos paradigmas \"do crime\" e \"do serviço\", bem como a inserção dos princípios da Análise do Comportamento nesta análise é um caminho promissor no combate à evasão fiscal. / Research on tax compliance has arisen in the economic field with seminal studies based upon the works of Allingham and Sandmo (1972) and Srinivasan (1973). Such articles were based on Becker\'s theory (1968) on crime and punishment, accepting the classic economic paradigm, which presupposes that individuals show rational behaviors. Nevertheless, in the past decades, many researchers have noticed that such paradigm, which gave rise to what is referred to, by the academy, as \"crime paradigm\", explained the behavior of taxpayers solely in part, and an entire line of research opposing such rational paradigm arose, based upon the verification that the behavior of taxpayers is much more complex than what was originally presumed, deserving a multidisciplinary analysis, i.e., not restricted to the economic field, but that, further, encompasses other subjects. Such new paradigm was designated by the academy as \"service paradigm\" that, in general, contemplates other factors involved in the act of paying taxes, including psychological factors, thus presupposing that taxpayers are not rational individuals solely concerned about maximizing the function thereof, they should be deemed, by the public administration, to be clients, and should receive appropriate treatment and quality public services in return for complying with their tax obligations. This study analyzes two paradigms, introducing in such analysis concepts of the science called Behavior Analysis, the teachings on learning and human behavior of which have potential to significantly contribute to better understanding the subject. Testing the theoretical assumptions presented throughout the study, two empirical analyses were conducted, based upon the model created by researcher and psychologist Erich Kirchler, referred to as Slippery Slope Model, which confirms previous studies and indicates that both punishment and reward are effective tools to fight against tax evasion, suggesting that integrating \"crime\" and \"service\" paradigms and inserting concepts of the Behavior Analysis Science in this analysis is highly promising to fight against tax evasion.
174

Effect of Environmental Factors on Pore Water Pressure in River Bank Sediments, Sollefteå, Sweden / Påverkan av miljöfaktorer på porvattentrycki flodbanksediment, Sollefteå, Sverige

Fritzson, Hanna January 2017 (has links)
Pore water pressure in a silt slope in Sollefteå, Sweden, was measured from 2009-2016. The results from2009-2012 were presented and evaluated in a publication by Westerberg et al. (2014) and this report is an extension of that project.In a silt slope the pore water pressures are generally negative, contributing to the stability of theslope. In this report the pore water pressure variations are analyzed using basic statistics and a connection between the pore water pressure variations, the geology and parameters such as temperature, precipitation and soil moisture are discussed.The soils in the slope at Nipuddsvägen consists of sandy silt, silt, clayey silt and silty clay. The main findings were that at 2, 4 and 6 m depth there are significant increases and decreases in the pore water pressure that can be linked with the changing of the seasons, for example there is a significant increase in the spring when the ground frost melts. As the seasons change, so do the temperature and amount and type of precipitation. Other factors that vary with the season are the amount of net radiation, wind speed and relative humidity, all of which affect the amount of evapotranspiration. At greater depths the pore water pressue is most likely affected by a factor/factors that varies from year to year, possibly the total amount of rainfall. Therefore, the anticipated increase in precipitation in Scandinavia due to climate change could be an important factor influencing slope stability.What precipitation, temperature and evapotranspiration have in common is that they affect the amount of water infiltrating the soil, and thereby the soil moisture content. How the soil moisture is distributed and flows through the soil (sub-surface flow) is governed by the different soil types and their mutual order in the slope, as well as by factors affecting the structure of the soil, e.g. animal burrows and aggregation. The formation of ground frost also affects the way in which the water present in the soil is redistributed.At c. 14 m depth in the slope, there is a saturated layer with positive pore water pressures, which could be one of several such layers. The overall groundwater situation in a silt slope is complex; several different bodies of water can develop, and to get a complete picture of the ground water situation (andthereby also the pore water pressure variations) thorough hydrological surveys are needed. / Under  2009-2016  mättes  porvattentrycket  i  en  siltslänt  i  Sollefteå.  Resultaten  från  2009-2012presenterades och utvärderades i en publikation av Westerberg et al. (2014) och detta examensarbete är en förlängning av det projektet.I en siltslänt är porvattentrycket vanligtvis negativt vilket bidrar till stabiliteten i slänten. I den härrapporten är variationerna av porvattentrycket analyserade med hjälp av enkel statistik och en koppling mellan variationerna och geologin samt parametrar så som temperatur, nederbörd och fukthalt i marken diskuteras.Jordarterna i slänten vid Nipuddsvägen består av sandig silt, silt, lerig silt och siltig lera. Slutsatsen var att på 2, 4 och 6 m djup ökade och minskade porvattentrycket med årstiderna, till exempel ökade porvattentrycket signifikant vid tjällossningen. När årstiderna skiftar ändras även temperaturen och mängden, och typen, av nederbörd. Andra faktorer som varierar över året är netto-instrålningen, vindhastigheten och den relativa fuktigheten och dessa faktorer påverkar i sin tur evapotranspirationen. På större djup beror antagligen portrycksvariationerna på någon eller några faktorer som skiljer sig åt från år till år, möjligtvis den totala mängden nederbörd. Därmed skulle den ökade nederbörd som förväntas i Skandinavien på grund av klimatförändringarna kunna påverka släntstabiliteten.Vad nederbörd, temeperatur och evapotranspiration har gemensamt är att de påverkar mängden vatten som infiltrerar marken, det vill säga de påverkar markens fukthalt. Hur vattnet är födelat i marken beror på de olika jordarterna och deras inbördes ordning i slänten, men också av faktorer som påverkar markens struktur så som aggregation och uppluckring av jorden på grund av marklevande djurs aktivitet. Även formationen av tjäle på vintern har troligtvis en viss inverkan på hur vattnet i marken omfördelas.På 14 m djup finns ett vattenmättat lager med positiva porvattentryck vilket skulle kunna vara ett av flera sådana lager. I en siltslänt är grundvattensituationen mycket komplex, flera magasin av vatten kan bildas. För att få en bra bild av grundvattensituationen (och där med också porvattentrycksvariationerna)behöver noggranna hydrologiska undersökningar genomföras.
175

Topografi och markfuktighet för granbarkborreskadad skog / Topography and soil moisture for spruce bark beetle damaged forest

Magnebäck, Anders, Fälth, Peter January 2020 (has links)
En stor skadegörare på de svenska granskogarna är den åttatandade granbarkborren Ips typographus (L.). Torkstress, vattentillgång och landskapets topografi är faktorer som påverkar granens vitalitet. Om granen har en låg vitalitet riskerar den i högre utsträckning att bli angripen av granbarkborren. Syftet med studien var att analysera topografi och markfuktighet för granbarkborreskadad skog. Områden med skadade träd och oskadade träd jämfördes i GIS-programmet QGIS för att se om det fanns en skillnad med avseende på markfuktighet, lutning, lutningsriktning och höjd över havet. Resultatet visade att granbarkborren angriper främst gran i syd till sydvästlig och östlig riktning. Även områden på torrare marker har en ökad risk för angrepp samt områden där terrängen inte sluttar. Troligtvis löper områden där ovan nämnda variabler sammanfaller större risk att bli angripna av granbarkborren.
176

Posouzení stability skalní stěny a návrh sanačních opatření / Assessment of the stability of rock walls and design of remedial measures

Nevřalová, Jana January 2015 (has links)
The work aims to evaluate rock slope including static assessment and to estimate the financial cost. Static analysis is done manually and the program GEO 5. The proposal remediation is performed in 6 combinations of which one is selected and processed into project documentation.
177

Analyse des processus de glissements gravitaires sous-marins par une approche géophysique, géotechnique et expérimentale : cas de la pente continentale de Nice / Analysis of submarine mass-movements processes through a geophysical, geotechnical and experimental approach : case study of the Nice continental slope

Kelner, Maëlle 21 December 2018 (has links)
Les glissements de terrains sous-marins, même de petite taille, représentent un risque majeur d’érosion littorale et de submersion marine lorsqu’ils sont déclenchés à proximité des côtes. Ce fut le cas à Nice (France) avec l’effondrement en mer d’une partie de la plateforme aéroportuaire, suivit d’un tsunami du fait d’un glissement sous-marin en octobre 1979. Du fait que la pente continentale niçoise soit abrupte, à proximité des côtes et soumise à une activité sismique modérée, elle constitue un véritable laboratoire naturel pour l’étude des glissements sous-marins de petite échelle. Ce travail repose sur une approche multidisciplinaire permettant une étude globale des processus de glissement dans la zone proximale. Il intègre des données issues de la géophysique marine, de la sédimentologie de la géotechnique et une phase préliminaire de modélisation numérique. Pour la première fois, la morphologie ainsi que l’architecture des dépôts du delta du Var ont été investigués à partir de données de très haute résolution. Elles ont permis d’identifier la signature de nombreux processus gravitaires de petite taille en surface (morphologie / taille / répartition spatiale) ainsi que leur imbrication en profondeur. Dans le cas du glissement de 1979, des éléments encore inconnus ont été identifiés tels que : 1) ses cicatrices Est et Ouest ; 2) des blocs et paquets glissés non évacués ; 3) la surface de glissement en profondeur ; 4) l’estimation d’un volume total déplacé différent du volume de sédiments évacués. Les carottes sédimentaires ont ensuite permis de discuter de la répartition en zone proximale des dépôts/érosion et de l’enregistrement de paléoglissement à partir de l’état de surconsolidation des dépôts. L’activité des glissements a été estimée dans le temps. Les plus grands glissements (V > 106 m3) ont des fréquences estimées ~50 ans, les glissements de taille moyenne (105 < V < 106 m3) autour de 3 à 25 ans, et les nombreux petits glissements (V < 105 m3) tous les 1-2 mois à 5 ans au cours des périodes actives des 50 dernières années. Ces glissements sont enregistrés dès la zone proximale à des fréquences de 3-7 ans au cours des périodes de plus forte activité depuis 400 ans. L’évolution de la morphologie suit des cycles successifs de déclenchement/quiescence/rechargement. À l’échelle de temps humaine deux cycles s’étendent de 1967-1999 et de 1999-2011 ; les ruptures se regroupent en cluster de 5-10 ans. À l’échelle pluriséculaire, les clusters de turbidites durent 20-40 ans et les périodes de quiescence ~100 ans. Enfin, cette étude apporte de nouvelles contraintes à propos des facteurs déclenchants ou préconditionnants agissant sur le delta du Var. L’état de stabilité de la zone semble être fortement préconditionné par la complexité de la topographie, l’état de consolidation des sédiments et l’importance des apports sédimentaires du Var. L’architecture des dépôts semble principalement contraindre la profondeur des instabilités. Parmi les forçages externes connus sur la zone, nous avons cartographié l’extension de la zone riche en gaz ainsi que des panaches de fluides dans la colonne d’eau. Notre analyse montre que l’amplitude des précipitations, des crues et du niveau de la nappe alluviale seraient trop faibles au cours des 50 dernières années pour agir en tant que facteur déclenchant de manière isolée. Afin de déstabiliser les pentes, ces forçages semblent devoir être couplés entre eux ou associés à l’action de séismes. Les analyses des bases de données en lien avec l’activité des glissements ainsi que les tests numériques permettent de suggérer que la sismicité régionale et que les séismes historiques sont soit 1) de magnitude trop faible, soit 2) à de trop grandes distances des zones de déclenchement, pour générer des PGA assez fort (0,2 g) et avoir individuellement un impact sur les pentes du Delta. / Small submarine landslides, when triggered near the coast represent a major coastal hazard due to erosion of the coastline and marine submersion. In October 1979, a submarine landslide generated a part of the airport platform of Nice (France) to collapse at sea and provoked a tsunami. Because the continental slope off this region is abrupt, close to the coast and subject to moderate seismic activity it is a natural laboratory to study small-scale submarine mass movements processes. This work is based on a multidisciplinary approach allowing a global study of landslide processes in the source area. It integrates data from marine geophysics, sedimentology, geotechnics and numerical modelling. For the first time morphology and architecture of the Var delta deposits are investigated using very high resolution data. It allows identification of numerous small-size gravitational processes signatures as well as their embedding at depth. In the case of the 1979 landslide previously unknown features are identified: 1) eastern and western scars, 2) in-situ blocks and lateral spreading’s traces, 3) in-depth sliding surface, 4) estimation of a total displaced volume, which is different from the evacuated sediment volume. The sedimentary cores are then used to discuss the proximal distribution of deposits, erosion and paleo-landslides records from the deposits overconsolidation. The landslide activity has been estimated over time in terms of return frequencies. The largest landslides (>106 m3) have return frequencies nearing 50 years; the medium-size landslides (105 > V > 106 m3) between 3 and 25 years; and the numerous small landslides (<105 m3) every 1-2 months to 5 years during the most active periods in the last 50 years. Landslides deposits recorded in the source area show return frequencies of 3-7 years during periods of greater activity over the last 400 years. The morphology’s evolution follows successive cycles of sliding/quiescence/reloading. In recent times, two main cycles can be observed (from 1967 to 1999 and from 1999 to 2011) during which triggering are clustered in 5-10 years. On a longer time scale, the turbidites clusters span 20-40 years and quiescence periods ~100 years. Finally, this study brings new constraints on preconditioning and triggering factors acting on the Var delta. The stability of the area seems to be strongly conditioned by the complexity of the topography, the sediments consolidation and the quantity of sediments brought by the Var river. The deposits architecture mainly constrains the depth of the instabilities. Among the external drivers known in the area the extension of the gas-rich zone as well as fluids plumes in the water column have been considered and mapped. Looking at other external drivers, the analysis shows that the magnitude of rainfall and floods, and the alluvial water level would be too low over the past 50 years to act as an isolated triggering factor. In order to destabilize slopes, these external drivers need to be tackled together or associated to earthquakes. Relationships between databases analyses, landslides activity and numerical tests suggest that regional seismicity and historical earthquakes are either too small or too distant from the source areas to generate sufficient peak ground acceleration (0.2 g) and to have an individual impact on the delta slopes.
178

Eigenvalue Problem for the 1-Laplace Operator

Milbers, Zoja 23 March 2009 (has links)
We consider the eigenvalue problem associated to the 1-Laplace operator. We define higher eigensolutions by means of weak slope and establish existence of a sequence of eigensolutions by using nonsmooth critical point theory. In addition, we deduce a new necessary condition for the first eigenvalue of the 1-Laplace operator by means of inner variations. / Wir betrachten das zum 1-Laplace-Operator gehörige Eigenwertproblem. Wir definieren höhere Eigenlösungen mittels weak slope und weisen die Existenz einer Folge von Eigenlösungen nach, indem wir die nichtglatte Theorie kritischer Punkte anwenden. Zusätzlich leiten wir eine neue notwendige Bedingung für den ersten Eigenwert des 1-Laplace-Operators mittels innerer Variationen her.
179

Optimization of Physical Properties for Ditches–Case Study: Kankberg, Maurliden and Renström-Petiknäs.

Ketema, Ghebriel Kidane January 2014 (has links)
It is important for practical and legal reasons that water and sediments in disturbed areas around the mining operation should be controlled. The construction of a well-designed drainage system that controls erosion and thus restores the proper hydraulic function of the surface is one of the most important post-disturbance features which should be done as part of the mining activities. However, even with the best planning and design, unless proper construction practices are adapted; both the disturbed and reclaimed areas are very much likely to be susceptible to erosion, sedimentation and stability problems. In order to tackle the problem, guidelines on how to design and construct the drainage system should be well prepared. The main objective of this study was to prepare guidelines for the proper design, construction and monitoring of the water drainage management system in the study areas (Kankberg, Maurliden and Renström-Petiknäs). This report has analysed the results from the outcome of HEC-RAS software for the case study of the new ditch around the Maurliden mine site and integrated with different guidelines. Based on the results of the HEC-RAS, the most common problems in the drainage system have been identified. Moreover the thesis project identified important physical parameters such as cross-sections and slopes of the representative ditch which affect the function of the ditch in the study areas. Hydraulic parameters such as velocity which is very important for designing the type of lining and also Froude number which is very important in identifying the type of flow whether it is super-critical, critical or sub-critical were identified. The latter helps to select the type of guideline to be used between steep slope and mild slope.
180

An Enhanced Data Model and Tools for Analysis and Visualization of Levee Simulations

Griffiths, Thomas Richard 15 March 2010 (has links) (PDF)
The devastating levee failures associated with hurricanes Katrina and Rita, and the more recent Midwest flooding, placed a spotlight on the importance of levees and our dependence on them to protect life and property. In response to levee failures associated with the hurricanes, Congress passed the Water Resources Development Act of 2007 which established a National Committee on Levee Safety. The committee was charged with developing recommendations for a National Levee Safety Program. The Secretary of the Army was charged with the establishment and maintenance of a National Levee Database. The National Levee Database is a critical tool in assessing and improving the safety of the nation's levees. However, the NLD data model, established in 2007, lacked a structure to store seepage and slope stability analyses – vital information for assessing the safety of a levee. In response, the Levee Analyst was developed in 2008 by Dr. Norm Jones and Jeffrey Handy. The Levee Analysis Data Model was designed to provide a central location, compatible with the National Levee Database, for storing large amounts of levee seepage and slope stability analytical data. The original Levee Analyst geoprocessing tools were created to assist users in populating, managing, and analyzing Levee Analyst geodatabase data. In an effort to enhance the Levee Analyst and provide greater accessibility to levee data, this research expanded the Levee Analyst to include modifications to the data model and additional geoprocessing tools that archive GeoStudio SEEP/W and SLOPE/W simulations as well as export the entire Levee Analyst database to Google Earth. Case studies were performed to demonstrate the new geoprocessing tools' capabilities and the compatibility between the National Levee Database and the Levee Analyst database. A number of levee breaches were simulated to prototype the enhancement of the Levee Analyst to include additional feature classes, tables, and geoprocessing tools. This enhancement would allow Levee Analyst to manage, edit, and export two-dimensional levee breach scenarios.

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