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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.
81

Návaznost ÚSES na prvky protierozní a protipovodňové ochrany v KPÚ / Teritorial system of ecological stability consistent to erosion control and flood protection in land consolidation

Strádalová, Lucie January 2013 (has links)
This thesis evaluates the elements of the Territorial system of stability, which were designed within the plan of the common facilities of comprehensive landscaping, with regards to the elements of the erosion and flood protection. Within the scope of this work there was proceeded the hydrological analysis on the parts of the watersheds of the specific cadastral territories of Lichnov and Šardice. esign of the ÚSES´s elements within the KPÚ at specific cadastral territories was further evaluated in terms of area of the individual elements anEcological stability the change after the design of these elements.
82

Noise Characteristics And Edge-Enhancing Denoisers For The Magnitude Mri Imagery

Alwehebi, Aisha A 01 May 2010 (has links)
Most of PDE-based restoration models and their numerical realizations show a common drawback: loss of fine structures. In particular, they often introduce an unnecessary numerical dissipation on regions where the image content changes rapidly such as on edges and textures. This thesis studies the magnitude data/imagery of magnetic resonance imaging (MRI) which follows Rician distribution. It analyzes statistically that the noise in the magnitude MRI data is approximately Gaussian of mean zero and of the same variance as in the frequency-domain measurements. Based on the analysis, we introduce a novel partial differential equation (PDE)-based denoising model which can restore fine structures satisfactorily and simultaneously sharpen edges as needed. For an efficient simulation we adopt an incomplete Crank-Nicolson (CN) time-stepping procedure along with the alternating direction implicit (ADI) method. The algorithm is analyzed for stability. It has been numerically verified that the new model can reduce the noise satisfactorily, outperforming the conventional PDE-based restoration models in 3-4 alternating direction iterations, with the residual (the difference between the original image and the restored image) being nearly edgeree. It has also been verified that the model can perform edge-enhancement effectively during the denoising of the magnitude MRI imagery. Numerical examples are provided to support the claim.
83

Ferrocyanide: An Inappropriate Reagent for ds-DNA Binding Mode Determination

Burya, Scott J. 11 September 2009 (has links)
No description available.
84

Modelagem hidrológica da bacia hidrográfica do rio Bengalas, Nova Friburgo, RJ, utilizando o potencial de geotecnologias na definição de áreas de risco de inundação.

Evaldo Flávio Gomes Correia 11 October 2011 (has links)
A presente pesquisa concentra-se no estudo hidrológico utilizando o potencial das geotecnologias na modelagem do escoamento na bacia do rio Bengalas, cujo rio principal de mesmo nome, corta o município de Nova Friburgo, RJ, no sentido Sul-Norte. Esse município, um dos mais importantes da região serrana, sofre frequentemente com inundações e deslizamentos, onde, dados históricos e acontecimentos recentes mostram que a ocupação inadequada de encostas e calhas dos rios são as áreas destacada e negativamente afetadas. A metodologia tem suporte no uso de um SIG, extraindo informações, que por sua vez, serão entrada de dados na fase de modelagem, e reforçando a apresentação dos resultados das simulações através de mapas. Ela está divida basicamente em três etapas: "SIG", "Modelagem" e "Suporte à Tomada de Decisão/Simulação". Esse primeiro estudo permitiu compor um banco de dados geográfico com as características fisiográficas da bacia; a seleção criteriosa de uma modelagem matemática e encadeamento de seus parâmetros com os componentes do ciclo hidrológico; realizar a calibração do modelo de transformação chuva-vazão, Soil Conservation Service (CN); e simular a passagem dos volumes gerados pela precipitação efetiva na calha do rio Bengalas, com o objetivo de identificar e analisar as áreas suscetíveis a inundações na porção central da cidade de Nova Friburgo. Modelagem dessa natureza vem sendo empregada, principalmente, no gerenciamento de recursos hídricos, onde a tomada de decisões embasada nos resultados de simulações computacionais, contribuem para evitar prejuízos materiais e financeiros, e ainda, perdas de vidas humanas em áreas de risco, neste caso, aquelas suscetíveis a inundações. Analisando os resultados encontrados temos que a área suscetível à inundação para uma chuva com tempo de recorrência de 50 anos, o mais crítico estudado, seja de aproximadamente 1,0 km, distribuídos nos seus 8,5km na região central de Nova Friburgo-RJ, sendo está, ora delimitada, prioritariamente edificada. / This research focuses on the hydrological study using the potential of geotechnology into runoff modeling of the Bengalas Basin, whose main river, with same name, crosses the city of Nova Friburgo - RJ, in a south-north orientation. This city, one of the most important in "Região Serrana", suffers often with floods and landslides, which, historical data and recent events show that the inappropriate occupation of hillsides and margins of rivers are the highlighted and negatively affected areas. The methodology has basis in a GIS application, extracting information, which in turn, are input in the modeling phase, and enhancing the presentation of simulation results through maps. It is basically divided into three stages: "SIG", "Modelagem" and "Suporte à Tomada de Decisão/Simulação." This first study allowed to compose a geographic database with the physiographic features of the basin; the careful selection of a chain of mathematical modeling and its parameters with the hydrological cycle components, perform the calibration of the rainfall-runoff transformation model, Soil Conservation Service (CN) and simulate the transition of volumes generated by an effective precipitation in the Bengalas river, in order to identify and analyze the susceptible flooding areas in the central part of Nova Friburgo. A kind of this modeling has been used, mainly, in the water resource management, in which decision-making are based on results of computer simulations, helps to avoid a range of losses, such as material, financial and, especially, humans, that in this case, people who lives in areas susceptible to flooding. Analyzing the results, it was found that an area susceptible to flooding by a rainfall with a recurrence time of 50 years, the most critical studied, results in approximately 1.0 km, distributed in its 8.5km (central part of Nova Friburgo - RJ) which this bounded area has a great part with buildings.
85

Modelagem hidrológica da bacia hidrográfica do rio Bengalas, Nova Friburgo, RJ, utilizando o potencial de geotecnologias na definição de áreas de risco de inundação.

Evaldo Flávio Gomes Correia 11 October 2011 (has links)
A presente pesquisa concentra-se no estudo hidrológico utilizando o potencial das geotecnologias na modelagem do escoamento na bacia do rio Bengalas, cujo rio principal de mesmo nome, corta o município de Nova Friburgo, RJ, no sentido Sul-Norte. Esse município, um dos mais importantes da região serrana, sofre frequentemente com inundações e deslizamentos, onde, dados históricos e acontecimentos recentes mostram que a ocupação inadequada de encostas e calhas dos rios são as áreas destacada e negativamente afetadas. A metodologia tem suporte no uso de um SIG, extraindo informações, que por sua vez, serão entrada de dados na fase de modelagem, e reforçando a apresentação dos resultados das simulações através de mapas. Ela está divida basicamente em três etapas: "SIG", "Modelagem" e "Suporte à Tomada de Decisão/Simulação". Esse primeiro estudo permitiu compor um banco de dados geográfico com as características fisiográficas da bacia; a seleção criteriosa de uma modelagem matemática e encadeamento de seus parâmetros com os componentes do ciclo hidrológico; realizar a calibração do modelo de transformação chuva-vazão, Soil Conservation Service (CN); e simular a passagem dos volumes gerados pela precipitação efetiva na calha do rio Bengalas, com o objetivo de identificar e analisar as áreas suscetíveis a inundações na porção central da cidade de Nova Friburgo. Modelagem dessa natureza vem sendo empregada, principalmente, no gerenciamento de recursos hídricos, onde a tomada de decisões embasada nos resultados de simulações computacionais, contribuem para evitar prejuízos materiais e financeiros, e ainda, perdas de vidas humanas em áreas de risco, neste caso, aquelas suscetíveis a inundações. Analisando os resultados encontrados temos que a área suscetível à inundação para uma chuva com tempo de recorrência de 50 anos, o mais crítico estudado, seja de aproximadamente 1,0 km, distribuídos nos seus 8,5km na região central de Nova Friburgo-RJ, sendo está, ora delimitada, prioritariamente edificada. / This research focuses on the hydrological study using the potential of geotechnology into runoff modeling of the Bengalas Basin, whose main river, with same name, crosses the city of Nova Friburgo - RJ, in a south-north orientation. This city, one of the most important in "Região Serrana", suffers often with floods and landslides, which, historical data and recent events show that the inappropriate occupation of hillsides and margins of rivers are the highlighted and negatively affected areas. The methodology has basis in a GIS application, extracting information, which in turn, are input in the modeling phase, and enhancing the presentation of simulation results through maps. It is basically divided into three stages: "SIG", "Modelagem" and "Suporte à Tomada de Decisão/Simulação." This first study allowed to compose a geographic database with the physiographic features of the basin; the careful selection of a chain of mathematical modeling and its parameters with the hydrological cycle components, perform the calibration of the rainfall-runoff transformation model, Soil Conservation Service (CN) and simulate the transition of volumes generated by an effective precipitation in the Bengalas river, in order to identify and analyze the susceptible flooding areas in the central part of Nova Friburgo. A kind of this modeling has been used, mainly, in the water resource management, in which decision-making are based on results of computer simulations, helps to avoid a range of losses, such as material, financial and, especially, humans, that in this case, people who lives in areas susceptible to flooding. Analyzing the results, it was found that an area susceptible to flooding by a rainfall with a recurrence time of 50 years, the most critical studied, results in approximately 1.0 km, distributed in its 8.5km (central part of Nova Friburgo - RJ) which this bounded area has a great part with buildings.
86

Vyhodnocení účinnosti komplexních ochranných opatření k.ú. Jerlochovice v povodí Husího potoka / Evaluating the effectiveness of complex protection measures in cadastral area Jerlochovice in Husí potok Watershed

Matoušek, Petr January 2015 (has links)
A subject of this Thesis is the design of the complex system of measures of soil conservation in given catchment area, which will serve as a concept of complex land consolidation in cadaster Jerlochovice. Based on the analysis and the land survey, a feasible solution was designed using the hydrological and erosive tools of ArcGIS. For the identification of areas endangered by erosion and for the identification of runoff conditions, the Universal Soil Loss Equation of Wischmeier-Smith was used (in grid modification). Based on the calculated values, the suitable technical and agrotechnical measures of soil erosion control were designed. Each component was designed for the values of Qn from the model DesQ. Subsequently the efectivity of the designed measures was evaluated by the comparison of results of erosive and runoff conditions before and after the aplication of the soil and water conservation measures.
87

Studie návrhu opatření proti nepříznivým účinkům povrchového odtoku v k.ú. Štefanov / The design of system territorial protection of build up area in cadastre Stefanov

Sabo, Rudolf January 2012 (has links)
This thesis is focused to determine water erosion of soil and drain from basin of štefanov stream. The basin of štefanov stream is unobserved with area 15,1 km2. After evaluation of current status is processed integrated design against the adverse effects of surface runoff.
88

Characterization of Landscape Structures and Precipitation in relation to Flooding events in Pampa Deprimida : A Minor Field Study in Argentina

Svärd, Linnea January 2023 (has links)
The purpose of the thesis is to characterize flood events within the agricultural fields of flooding Pampa in Argentina. The characterization divides the flat landscape into flood prone areas and endeavour at linking driving factors to flood response based on past events. The characterization is based on information freely available from remote sensing (satelliteimages, digital elevation, and estimated rain data), from precipitation data from a weatherstation and from field measurements carried out with Universidad Nacional de La Plata. The main research question is: Which are the driving factors contributing to the flooding? Data from remote sensing was used to visualize previous areal water extents, to calculate the topographic wetness index, the upslope areas for the field study sites and for a precipitationtrend analysis. Furthermore, data from remote sensing was used to replace missing days of rain data from the weather station. The complemented rain data was compared with the water extent for the events. Relationships between event precipitation, previous precipitation, land-use, and surface runoff was evaluated with the Soil Conservation-Curve Number method, SCS-CN, and the runoff coefficients for different antecedent conditions were calculated. The precipitation data and the satellite images showing water extents were also used to calculatethe 100-year and 20-year storm- and flood event. The measured infiltration capacity was used as input data in the SCS-CN-method to calculate the surface runoff and the measured soilmoisture was used to verify results from the Topographic Wetness Index, TWI, map. The flood risk areas are visualized with satellite images and the calculated Modified Normalized Difference Water Index. The TWI also visualizes the more flood prone or wetter areas and delineates the lower depressions where soil moisture was also measured to be higher, however not significantly. With the available satellite images within the study results indicate that floods are more common wintertime and that great flood events cannot be foreseen with only antecedent precipitation and event precipitation with the SCS-CN method. However, the events in the study with larger water extents, had high precipitation. No clear correlation between water extents from satellite images calculated by Instituto Nacional de Tecnología Agropecuaria, and estimated surface runoff from the SCS-CN method could be seen. However, the obtained runoff coefficients from the SCS-CN method can be used for estimating surface runoff for future storm events were higher Antecedent Moisture Condition, AMC, and low infiltration capacities increases surface runoff. The infiltration capacity of the studied fields is approximately 16 mm/hour and hence not alone a driving factor causing inundation since the soil can absorb, for example, a 20-year storm event of 125 mm/day. However, that is not the case since a 20-year storm flood has covered 9 % of the area around Don Joaquin and El Amanecer with water. No seasonal precipitation trends can be seen in Punta Indio during the last 40 years analysing precipitation data from remote sensing. In flooding Pampa the agricultural fields inundate almost on yearly basis in the depressionsdue to the gentle slopes and high intense precipitation (yearly maximum daily precipitation is always higher than 60 mm/day). To decrease the flood risk the management should ensure high vegetative cover which increases infiltration and balances the hydrological responses. / Syftet med studien är att karakterisera översvämningar inom jordbruket på Argentinska Pampas. Det platta landskapet mest översvämningsutsatta områden pekas ut och arbetet har fokuserat på att koppla landskapets utformning och regnmönster till översvämningarna. Karakteriseringen utgår ifrån information från satellitbilder och digitala höjddata, från nederbördsdata från den närmaste väderstationen som kompletterats med regndata från fjärranlyser och från fältmätningar utförda tillsammans med Universidad Nacional de La Plata. Den huvudsakliga frågan är: Vilka är de bidragande faktorerna till översvämningarna? Information från fjärranalyser användes för att visualisera tidigare översvämningar, för att beräkna det topografiska fuktighetsindexet, tillrinningsområdet för fältstudieplatserna och för en nederbördstrendanalys. Regndatan jämfördes med vattenarean under tidigare översvämningar. Sambanden mellan nederbörd, markanvändning och ytavrinning utvärderades med Soil Conservation-Curve Number metoden, SCS-CN, och avrinningskoefficienterna för olika nederbördsförhållanden beräknades. Nederbördsdata och satellitbilder som visar vattnets utbredning användes också för att beräkna magnituden av ett 100-årsregn och 20-årsregn samt utbredningen av en 100-årsöversvämning. Den i fält uppmätta infiltrationskapaciteten användes som indata i SCS-CN-metoden för att beräkna ytavrinning och den i fält uppmätta markfuktigheten för att verifiera resultat från GISanalysen av det topografiska fuktighetsindexet.' Översvämningsriskområden visualiserades i studien med satellitbilder och det modifierade normaliserade differens vattenindexet. Även det topografiska fuktighetsindexet visualiserar de mer översvämningsbenägna områdena och markerar vattnets väg där markfuktigheten också uppmättes vara högre, dock inte signifikant blötare än ovan liggande punkter. Analys av de tillgängliga satellitbilderna i studien visar att översvämningar är vanligare vintertid och att stora översvämningshändelser inte kan förutses enbart med de senaste dagarnas regnmängd och eventregnet med SCS-CN-metoden. Alla satellitbilder i studien med större vattentäckning kunde dock kopplas till stora regnmängder. Ingen tydlig korrelation mellan vattenutbredningen och uppskattad ytavrinning med SCS-CN-metoden kunde ses. De erhållna avrinningskoefficienterna från SCS-CN-metoden kan dock användas för att uppskatta risken för ytavrinning vid framtida regn där större regnmängder och låg infiltration ökar ytavrinningen. Fältens infiltrationskapacitet är cirka 16 mm/timme och därmed inte ensamt en drivande faktor till översvämningarna eftersom infiltrationskapaciteten är högre än exempelvis ett 20-årsregn (125 mm/dygn). Dock kan 20-årsregn täcka 9 % av området runt Don Joaquin och El Amanecer med vatten. Inga nederbördstrender kan ses i Punta Indio under de senaste 40 åren genom analys av nederbördsdata från fjärranalyser. I Pampa deprimida översvämmar jordbruksfälten nästan årligen i sänkorna på grund av den platta topografin och den höga intensiva nederbörden (den årliga maximala dagliga nederbörden är nästan alltid högre än 60 mm/dag). För att minska översvämningsriskerna bör lantbrukare säkerställa en hög vegetativ täckning som ökar infiltrationen, skyddar marken och balanserar de hydrologiska reaktionerna. / El propósito de la tesis es analizar los posibles eventos de inundación en un sector de la Pampa Deprimida en Argentina, dada la importancia productiva de la región. Se trabajó en los campos de la Universidad Nacional de La Plata con la dirección del curso de Edafología, de la Facultad de Ciencias Agrarias y Forestales. Se caracterizó la región en general y los campos en particular, utilizando información de acceso gratuito en la web, tales como imágenes satelitales, mapas de elevación digital e información meterologíca. Se utilizaron técnicas geomáticas para definir la evolución de agua en superficie mediante un análisis de la precipitación y coberturas de agua en imágenes satelitales obtenidas entre el 2000 y 2022 con la finalidad de calcular el Indice de Humedad Topográfico (TWI). Se establecen relaciones entre la precipitación, el manejo de los campos, la escorrentía superficial y las cuberturas de aguas. Se analizó la occurrencias de eventos de excesos hídricos. Se efectuaron ensayos de infiltración y el método Soil Conservation Service-Curve Number (SCS-CN) a fin de estimar la escorrentía superficial y las medidas de la humedad del suelo para verificar los resultados del mapa con el TWI. Las imágenes satélitales y el Modified Normalized Differential Water Index (MNDWI) calculado, permiten estimar las áreas más expuestas a inundaciones. El TWI permitió distinguir los sectores más altos y bajos mediante la medición de la humedad del suelo. Con los datos disponibles en este estudio, los resultados indican que las inundaciones son más frecuentes en invierno, y que los grandes eventos de inundación no se pueden predecir solo con registros de precipitación y el uso del método SCS-CN. No se pudo observar una correlación entre las extensiones de agua de las imágenes satelitales calculadas por Instituto Nacional de Tecnología Agropecuaria (INTA Clima y Agua, Castelar), y la escorrentía superficial estimada por el método SCS-CN. Sin embargo es possible encontrar una correspondencia entre las precipitaciones muy elevadas y la cobertura de agua. La occurencia de altas precipitaciones luego de un periodo lluvioso en un suelo con baja infiltración debido a una baja cobertura vegetal, aumenta la escorrentía superficial. La capacidad de infiltración del campo estudiado es de aproximadamente 16 mm/hora y un evento de lluvia extrema que se produce cada 20 años puede ser de 125 mm/día. Consecuentemente, no sería la baja infiltración la principal causa de la inundacion. No obstante, se aprecia que effectivamente un evento de 125 mm/día cubre 9 % del área en Don Joaquín y del El Amanecer. Con precipitaciones normales la cobertura es de aproximadamente 2 %. Cabe indicar que las precipitaciones registradas en la estación de Punta Indio durante los últimos 40 años, no manifiestan un comportamiento diferente en su occurencia y cantidad. En Pampa deprimida los campos se inundan frecuente, no solo debido a las precipitaciones locales y el amabiente de muy bajas pendientes. Los flujos de agua subterranea, aunque no se las pudo analizar en este estudio, también afuectuan las coberturas de agua. A fin de disminuirlos riesgos de inundación, el manejo debe garantizar una alta cobertura vegetal que aumente la infiltración y proteja al suelo y, de este modo, contribuir a controlar la natural dinámica hidrológica de la región en estudio. / Estudio del suelo, agua subterránea y vegetación, como base para definir ambientes de manejo en el partido de Magdalena
89

Spectroscopie moléculaire : calcul de spectres, mesures des températures de rotation et de vibration dans les plasmas thermiques

Faure, Géraldine 05 December 1997 (has links) (PDF)
Ce travail porte sur le diagnostic des températures de vibration et de rotation des molécules dans les plasmas thermiques.<br /><br />Ce mémoire comporte deux grandes parties : l'une concerne le calcul de spectres moléculaires et la deuxième partie est consacrée à la comparaison des spectres dans quatre cas expérimentaux différents.<br /><br />Un code de calcul a été réalisé pour simuler des spectres d'espèces diatomiques. Ce code a été essentiellement appliqué aux radicaux C2, CN, à la molécule N2 et à l'ion N2+ avec comme paramètres variables les températures de vibration et de rotation. Cette partie commence par une description de la molécule diatomique et de ses propriétés. <br />Ensuite la méthode pour calculer les spectres est explicitée : <br />détermination des longueurs d'onde,<br />de leur intensité,<br />application d'une fonction d'appareil,<br />obtention du spectre final. <br />L'influence des températures de rotation et de vibration sur les intensités des raies est prise en compte ainsi que celle de la fonction d'appareil. Ces spectres sont calculés, pour une expérience donnée, de manière à déterminer ces deux paramètres par comparaison avec les spectres obtenus par la mesure.<br /><br />Cette méthode a été utilisée sur quatre plasmas différents : <br />une flamme oxy-acétylénique,<br />un arc stabilisé dans une chambre de Maecker,<br />une torche à plasma ICP,<br />une décharge entre deux électrodes liquides. <br />Les températures de rotation et de vibration ont été déterminées par la comparaison de spectres. Ainsi des profils de températures ont pu être réalisés.<br /><br />En annexe, les valeurs numériques nécessaires aux calculs de spectres sont répertoriées pour le système de Swan de C2, le système violet de CN, le second système positif de N2 et le premier système négatif de N2+.
90

Řešení protierozní ochrany na modelovém projektu komplexní pozemkové úpravy / Solution erosion protection on a Complex Land Consolidation model

SVOBODOVÁ, Pavlína January 2013 (has links)
The aim of this work is to explore the area of the Complex Land Consolidation Poněšice in the view of the pedology, hydrogeology and climatology. Further make a erosion threat calculations using the USLE and Curve Number method and afterwards review the application of the erosion control measures in another section of the chapter Main terriorial systems. In conclusion, to estimate the economic aspects of the proposed measures.

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