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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.
101

Avaliação do posicionamento plano-altimétrico com receptor gps em diferentes tipos de uso do solo /

Itame, Otávio Yassuo, 1956- January 2008 (has links)
Orientador: Zacarias Xavier de Barros / Banca: José Milton Arana / Banca: Osmar Delmanto Junior / Banca: Lincoln Gering Cardoso / Banca: Vilmar Antonio Rodrigues / Resumo: Neste trabalho, foram realizados levantamentos topográficos para a avaliação do efeito da cobertura vegetal, na recepção de sinais GPS, para obtenção de posicionamento tri-dimensional, considerando os estudos realizados em diferentes tipos de uso do solo. Vértices foram implantados em diferentes tipos de uso do solo; em área com pastagem, com plantação de seringueiras e com eucaliptos, e as suas posições determinadas com estação total, nivelamento geométrico e com receptores GPS. Na avaliação do posicionamento altimétrico adotou-se como valores de referência os desníveis determinados com o nivelamento geométrico para avaliação dos dados obtidos com receptores GPS. As coordenadas planimétricas obtidas com receptores GPS foram analisadas utilizando-se com valores de referência os dados obtidos com a estação total. No levantamento topográfico com estação total foram adotadas as prescrições estabelecidas nas Normas da Associação Brasileira de Normas Técnicas (ABNT) NBR 13.133, Execução de Levantamentos Topográficos, para poligonais do tipo IVP. Foi realizada a análise de exatidão e de precisão do posicionamento tridimensional, adotando como padrão a NBR 13133 da ABNT para a classe do levantamento executado. Para aplicações do GPS na altimetria há necessidade do conhecimento da ondulação geoidal (N), que neste trabalho, para a sua determinação foram coletados dados com receptor na referência de nível (RN). Os resultados obtidos indicam que cuidados especiais devem ser tomados nos levantamentos com receptores GPS em áreas com cobetura vegetal, pois estas interferem na propagação das ondas eletromagnéticas provenientes dos satélites podendo inviabilizar o posicionamento. / In this work, topographic surveys were carried out in order to evaluate the effect of vegetal cover, on the reception of GPS signals, for 3D positioning, considering studies to be made in different types of land use. Points were set up on different types of land use, in areas containing grass, rubber trees and eucalyptus, which had their positions defined using a total station, geometric leveling and GPS receivers In the evaluation of height positioning it was adopted as reference values the height differences determined by geometric levelling in order to evaluate data obtained through GPS receivers. Planimetric coordinates obtained by using GPS receivers were analysed using as reference values the data obtained using a total station. During the topographic survey using a total station the recommendations set up by the Brazilian Association for Technical Rules (ABNT) NBR 13.133, regarding the execution of topographic surveys, for transverses of type IVP. Accuracy and precision analysis was made on the 3D positioning, also considering ABNT NBR 13.133, for the class of topographic survey which was carried out. In order to apply GPS on height positiong it is necessary to know the geoidal ondulation (N) and, in this work, N was computed based upon data acquired employing receivers at the level reference (RN). The results obtained indicate that special care must be taken during the surveys carried out with the use of GPS receivers on areas with vegetal cover, because it causes interference in the propagation of electromagnetic waves from the satellite which can even make the positioning become unviable. / Doutor
102

Disponibilidade e aplicabilidade de dados espaciais na caracterização e quantificação de perdas de solo por erosão na bacia hidrográfica do Rio Samambaia, Goiás / Availability and applicability of spatial data in the characterization and quantification of soil erosion in the Samambaia River watershed, Goiás

Botelho, Thiago Henrique Arbués 26 February 2015 (has links)
Submitted by Cláudia Bueno (claudiamoura18@gmail.com) on 2016-06-02T17:44:33Z No. of bitstreams: 2 Dissertação - Thiago Henrique Arbués Botelho - 2015.pdf: 8613837 bytes, checksum: 09a30216ecc0fd5f4e488e8223e6a47c (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-06-03T12:39:43Z (GMT) No. of bitstreams: 2 Dissertação - Thiago Henrique Arbués Botelho - 2015.pdf: 8613837 bytes, checksum: 09a30216ecc0fd5f4e488e8223e6a47c (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2016-06-03T12:39:43Z (GMT). No. of bitstreams: 2 Dissertação - Thiago Henrique Arbués Botelho - 2015.pdf: 8613837 bytes, checksum: 09a30216ecc0fd5f4e488e8223e6a47c (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2015-02-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The monitoring of soil loss by erosion is a source of information relevant to land management, forecasting impacts and conservation recommendations. In this sense, the objective of this study was to apply computer simulation methodology of soil erosion using the Universal Soil Loss Equation (USLE) and sources of information available to characterize, quantify and analyze soil losses in the Samambaia River watershed (BHRS). This basin was chosen as the study unit, due to the availability of spatial data in different scales (1: 250,000 and 1: 10,000). A Geographic Information System (GIS) was used in handling, sorting and updating of data of interest as well as to build the Digital Elevation Model (DEM) and the spatial database of USLE factors in two different scales. To quantitatively analyze the results calculated the Natural Potential Erosion (PNE) and the current erosion (Ea) that considers the influence of coverage, Land Use and Occupancy (UCS), also used for qualitative studies of soil losses. The study area was divided into three sub-basins. The mapping of the UCS showed that agricultural areas represent about 70% of land cover in the sub-basin of Samambaia River and Arrasta-burro Stream. The results indicated that more than 80% of the area of these two sub-basins has a weak PNE. Have the sub-basin of Moreira Stream had the highest percentage of natural vegetation and forestry classes, as well as the lowest percentage of bare soil class, in relation to other sub-basins. However, had the highest average value of current erosion (71.10 Mg ha-1 yr-1), which is probably due to the PNE ranging from moderate to very strong in more than 40% of the area. Most of the basin soil has medium erodibility. For Cambisols and Petric Plinthosols of BHRS, the average soil loss is at least twice higher than the average level of tolerance. The LS factor has more influence in the PNE, especially when the relief was wavy, followed by the K factor, when the relief was flat. Use the database scale 1: 10,000 affected area of the watershed caused increases in slope and rise of strong corrugated relief classes, mountainous and rugged, yet showed higher coefficients of variation for all the factors of USLE. The results show greater difference between the wavy relief classes in both applied scales. In most maps produced by means of databases on different scales there is distinction of the results, especially for the slope maps, PNE and Ea generated for the watershed of the Samambaia. The analysis of soil losses in the areas of central pivot showed higher average and median values when using the scale 1: 250,000. It is important that managers and farmers are aware of the risks and provide mitigation measures. An interesting solution is to expand the use of lower impact to soil management systems, to promote its wider coverage, such as forestry, especially in the areas susceptible to erosion. / O monitoramento das perdas de solo por erosão é fonte de informação relevante para a gestão do território, previsão de impactos e recomendações conservacionistas. Nesse sentido, o objetivo deste estudo foi aplicar metodologia de simulação computacional da erosão hídrica do solo utilizando a Equação Universal de Perda de Solo (USLE) e fontes de informação disponíveis para caracterizar, quantificar e analisar as perdas de solo na bacia hidrográfica do Rio Samambaia (BHRS). Essa bacia hidrográfica foi escolhida como unidade de estudo, em razão da disponibilidade de dados espaciais em escalas distintas (1:250.000 e 1:10.000). Um Sistema de Informação Geográfica (SIG) foi utilizado na manipulação, classificação e atualização dos dados de interesse, bem como para construir o Modelo Digital de Elevação (MDE) e a base de dados espaciais dos fatores da USLE nas duas escalas distintas. Para analisar quantitativamente os resultados calculou-se o Potencial Natural à Erosão (PNE) e a Erosão atual (Ea) que considera a influência da Cobertura, Uso e Ocupação do Solo (UCS), também usado para estudos qualitativos das perdas de solo. A área de estudo foi dividida em três sub-bacias hidrográficas. O mapeamento do UCS demonstrou que as áreas agrícolas representam aproximadamente 70% da cobertura do solo na sub-bacia do Rio Samambaia e do Córrego Arrasta-burro. Os resultados obtidos indicaram que mais de 80% da área dessas duas sub-bacias possui um PNE fraco. Já a sub-bacia do Ribeirão Moreira apresentou o maior percentual das classes vegetação natural e silvicultura, bem como o menor percentual da classe solo exposto, em relação às outras sub-bacias. Contudo, obteve o maior valor médio de erosão atual (71,10 Mg ha-1 ano-1), o que se deve provavelmente em razão do PNE que variou de moderado a muito forte em mais de 40% da área. A maioria dos solos da bacia apresenta média erodibilidade. Para os Cambissolos e Petroplintossolos (Plintossolos Pétricos) da BHRS, a perda média de solo está no mínimo duas vezes acima do limite médio de tolerância. O fator LS tem maior influência no PNE, principalmente quando o relevo foi ondulado, seguido pelo fator K, quando o relevo foi plano. O uso da base de dados na escala 1:10.000 afetou a área da microbacia, provocou aumento de declividade e surgimento das classes de relevo forte ondulado, montanhoso e escarpado, ainda apresentou maiores coeficientes de variação para todos os fatores da USLE. Os resultados comprovam maior diferença entre as classes de relevo ondulado nas duas escalas aplicadas. Na maioria dos mapas produzidos por meio das bases de dados em diferentes escalas existe distinção dos resultados, principalmente para os mapas de declividade, PNE e Ea gerados para a microbacia do Rio Samambaia. A análise das perdas de solo nas áreas de pivô central demonstrou aumento dos valores de média e mediana ao se utilizar a escala 1:250.000. É importante que os gestores e produtores rurais tomem consciência sobre os riscos e estabeleçam medidas mitigadoras. Uma solução interessante é ampliar a utilização de sistemas de manejo menos impactantes ao solo, que promovam sua maior cobertura, tais como a silvicultura, especialmente nas áreas mais suscetíveis à erosão.
103

Impact of ocean waves on deep waters mixing and large-scale circulation / L'incidence des ondes océaniques sur le mélange des eaux profondes et la circulation grande échelle

Richet, Oceane Tess 06 December 2017 (has links)
Les différents projets présentés dans cette thèse contribuent à la compréhension de plusieurs aspects clés de la circulation océanique. Le premier aspect que nous étudions porte sur les processus physiques à l'origine du mélange lié à la marée; deux processus ont été mis en évidence. Depuis la latitude critique vers l'équateur, la marée interne transfert son énergie à des ondes plus petite échelle via des instabilités triadiques résonnantes impliquant les ondes proche inertielles. Depuis la latitude critique vers le pôle, les ondes de marée interne continuent de transférer leur énergie à des ondes plus petite échelle, mais étonnamment ce transfert se fait entre la marée interne et des ondes évanescentes.Dans la deuxième étude, nous étudions l'effet d'un courant moyen sur la propagation et la dissipation des ondes de marée interne, générées à la topographie dans des simulations haute résolution. Dans ce cas, la dépendance en latitude de la dissipation de la marée interne est plus lisse et plus proche d'une constante. Ce changement de la dépendance en latitude peut être lié au décalage des fréquences des ondes de marée interne par effet Doppler, ce qui induit la génération d'ondes secondaires plus petite échelle.Dans la troisième étude, nous étudions l'effet d'une perturbation générée en amont sur la circulation dans le bassin amont dû à l'interaction entre la perturbation et un seuil hydrauliquement contrôlé. Les ondes de Kelvin et topographiques de Rossby, générées par une variation de l'afflux d'eau dans le bassin amont, perturbent l'écoulement au dessus du seuil et ainsi l'export d'eau. Cette perturbation est due à la réfraction des ondes sur le seuil à chaque passage, une fois qu'elles ont fait le tour du bassin amont. / The various projects presented in this thesis contribute to our understanding of various key aspects of the oceanic circulation. The first aspect that we investigate is the physical processes responsible for this tidal mixing, and we identify two processes. Equatorward of the critical latitude, internal tides transfer their energy to smaller-scale waves via triadic resonant instabilities involving near-inertial waves. Poleward of the critical latitude, internal tides still transfer energy to smaller-scale waves, but surprisingly this transfer takes place between the internal tide and evanescent waves.In the second study, we investigate the effect of a mean current on the propagation and the dissipation of internal tides generated at the topography in high-resolution simulations. In that case, the latitudinal dependence of the tidal energy dissipation is found to be smoother and closer to a constant. This change in the latitudinal dependence can be linked to the Doppler shift of the frequency of the internal tides, which impacts the generation of smaller-scale secondary waves.In the third study, we study the effect of an upstream disturbance on the upstream circulation by interaction with a hydraulically controlled sill. The Kelvin and topographic Rossby waves, generated by a change in the upstream inflow, perturb the flow through the channel and hence the water export. This perturbation is due to the refraction of the waves at the sill at each passage, once they go around the upstream basin.
104

Johnson City Topographic Region - 1955

U.S. Geological Survey 01 January 1955 (has links)
Large topographical map of the northeast Tennessee region around Johnson City published in 1955. Prepared by the Army Map Service, Corps of Engineers, U.S. Army, Washington D.C. Compiled in 1951 from United States Quadrangles, U.S. Geological Survey, and county highway maps. Planimetric detail partially revised by photo-planimetric methods. Control by USC & GS, TVA, and CE. Roads, railroad and aeronautical data verified by state authorities, 1954. Legend denotes populated places, types of roads, and railroads. Topography, names of roads, communities, and waterways can be found on the map itself. Physical copy resides in the Government Information, Law and Maps Department of East Tennessee State University’s Sherrod Library. Scale - 1: 250,000 / https://dc.etsu.edu/rare-maps/1043/thumbnail.jpg
105

Computational Delineation of Built-up Area at Urban Block Level from Topographic Maps: A Contribution to Retrospective Monitoring of Urban Dynamics

Muhs, Sebastian 20 May 2019 (has links)
Among many others, one general goal of the UN sustainability strategies aims at reducing the anthropogenic land change due to land take for settlements and transport infrastructure. To monitor the success of this goal and to comprehensively study and better understand these urban dynamic processes – such as densification, growth and sprawl, or shrinkage –, quantitative measurements were introduced to assist the assessment. For the analysis of urban dynamics, the built-up area is an important measure that can be considered at different scales, one common scale being the aggregated level of urban blocks that represent a group of developed parcels bounded by topographic borders such as street lines. Regardless of the scale of quantitative analysis, however, digital spatio-temporal data are essential. While comprehensive databases exist for contemporary data, they usually lack a historic dimension. To derive these historic data about the built-up area, potential surveying methods and sources may vary. Considering the long-term characteristic of urban land change, however, topographic maps often are the only source for small-scale, spatially explicit land cover information to build a comprehensive, spatio-temporal database of built-up area, which has been demonstrated by numerous studies. However, the manual constitution of historic geographic data based on historic maps – commonly referred to as map digitization or vectorization – is a time consuming and laborious process that limits the spatial and temporal scope and, therefore, opposes comprehensive studies. Therefore, this thesis proposes an approach to automatically extract information about the built-up area at urban block level from historic topographic maps. For a number of reasons, this is a challenging task. First, topographic maps show a high degree of informational density and complexity due to their layer concept. These layers of geographic objects generally overlap leading to the (multi-)fragmentation or fusion of distinct geographic map objects. While this may not pose a challenge to a human interpreter, it does for the formalization of the computational object recognition. Second, material aging of the document as well as a poor scanning or image compression process may result in a reduced graphical quality. Third, object representations including the use of color, if present at all, show an immense diversity over space and time. To overcome these challenges in regard to cartographical image analysis, a modular process has been designed pursuing a two-step strategy: a decomposition of salient map layers is succeeded by a re-composition of the structuring map objects to delineate the built-up area at urban block level. Several experiments prove this process to achieve acceptable results with correctness values ranging from 0.97 to 0.93 for three German study maps. Behind the background of a global trend to digitize knowledge that can also be observed with historic topographic maps, the designed process represents a promising approach to efficiently prepare these historic data for integration into a spatio-temporal database of built-up area with minimal user intervention.:Declaration of Authorship Acknowledgements Summary Contents List of Figures List of Tables List of Abbreviations 1 Introduction 1.1 Scope 1.2 Challenges 1.3 Research Questions 1.4 Structure 2 Principles of Image Analysis 2.1 Human Visual Perception 2.2 Methods of Image Analyis 2.2.1 Image Segmentation 2.2.1.1 Color Image Segmentation 2.2.1.2 Texture-based Segmentation 2.2.1.3 Morphology-based Segmentation 2.2.1.4 Further Segmentation Approaches 2.2.2 Object/Pattern Recognition 2.2.2.1 Strategies in Pattern Recognition 2.2.2.2 Approaches in Pattern Recognition 2.2.3 Object Reconstruction 2.2.3.1 Reconstruction of Contours 2.2.3.2 Raster-vector Conversion 2.3 Summary 3 Cartographic Image Analysis 3.1 Geoinformation from Cartographic Raster Maps 3.1.1 Raster Maps 3.1.2 Research History 3.1.3 Research – State of the Art 3.1.3.1 Separation of Raster Layers based on Color 3.1.3.2 Extraction and Recognition of Map Objects 3.1.3.3 Automated Georeferencing 3.1.4 Delineation of Built-up Area from Cartographic Raster Maps 3.2 Further Sources for the Delineation of Built-up Area 3.3 Summary and Interim Conclusions 4 Concept and Methodology 4.1 Concept - Preliminary Considerations 4.1.1 Defining the Subject of Delineatoin – the Urban Block 4.1.2 Data Characteristics 4.1.3 Cartographical Representation and Higher-Level Demarcation of Built-up Area 4.2 Methodological Design 4.2.1 Requirements to the Process and the Input Data 4.2.2 General Methodical Approach 4.2.3 Derivation of the General Delineation Process 4.2.4 Module Map Objects 4.2.4.1 Building Symbols 4.2.4.2 Residential Area Hatching 4.2.4.3 Railroads and Tramlines 4.2.5 Module Street Block Delineation 4.2.5.1 Street Network 4.2.5.2 Reconstruction of Street Block Objects 4.2.5.3 Evaluation of Street Block Objects 4.2.6 Delineation of Built-up Area 4.2.6.1 Module Building Grouping 4.2.6.2 Module Built-up Area 4.3 Implementation 5 Evaluation and Discussions 5.1 Evaluation Frameset 5.1.1 Study Maps 5.1.2 Reference Data 5.1.3 Methodology 5.2 Experiments and Results 5.2.1 Experiments 5.2.1.1 E.0 – Delineate Built-up Area Using the General Process 5.2.1.2 E.1 – Delineate Built-up Area Using a Deviation of the General Process 5.2.1.3 E.2 – Delineate Built-up Area Using Maps with Varying Spatial Resolution 5.2.2 Results 5.2.2.1 R.0 – Delineation Results of the General Process 5.2.2.2 R.1 – Delineation Results of the Deviated Process Variants 5.2.2.3 R.2 – Delineation Results of the Deviated Map Resolution Variants 5.3 Discussions 5.3.1 Strengths and Limitations 5.3.2 Comparision of Delineation Results to other Studies 5.3.3 Applications and Transferability to other Maps 6 Conclusion and Outlook 6.1 Revising the Research Questions 6.2 Scientific Contribution 6.3 Future Research Perspectives References Appendix A.1 List of Process Parameters and their Application A.2 Exemplary Delineation Results
106

A Comparison of Mixed Integer Programming and a Heuristic Approach for Harvest Blocking in Australia

Taylor, Ronald Gordon 07 May 2016 (has links)
The goal of harvest scheduling is to produce a practical operations schedule that can be implemented in the field by operational foresters and maximizes all values. The resulting harvest units need to represent a close approximation to what will be done operationally and while emulating natural disturbance regimes and topographic boundaries. using flow direction surfaces. Two methods of meeting spatially acceptable harvest units through a heuristic algorithm and a mixed integer programming method. A factor analysis was conducted on both to determine the statistical significance between 3 forest characterizations and mean financial and shape index indicators. Mixed integer programming had higher cash flows and net present values per hectare and the heuristic method had higher net present value per cubic meter at the 95% level of significance.
107

Improved Environmental Characterization to Support Natural Resource Decision Making: (1) Distributed Soil Characterization, and (2) Treatment of Legacy Nutrients

Buell, Elyce N. 27 September 2022 (has links)
Environmental concerns are becoming increasingly relevant during a period of hemorrhaging ecosystem goods and services. Restoring these would result in positive outcomes for public health and economic benefit. This thesis seeks to address two environmental concerns: (1) accurate soil mapping and (2) treatment of nitrogen to affect water quality change.The current method of soil mapping, SSURGO (USDA‐NRCS Soil survey), is often erroneous and misleading. Two studies in this dissertation are conducted to evaluate the potential that different resolution digital elevation models (DEMs) have to distribute soil characteristics successfully. These studies are conducted in southwest Virginia and western Vermont. The aforementioned studies evaluated 36 and 59 soil samples, respectively. Spatial characteristics, including slope, catchment area, and topographic wetness, are derived from several DEMs. In chapter 2, these characteristics are spatially compared, and we found that small resolution rasters result in narrow flow paths relative to coarser rasters. In chapter 3, we isolate the analysis to focus on resolution size, instead of a mix of both resolution size and generation method. This is done by recursively coarsening small rasters, deriving spatial attributes from said rasters and evaluating their potential to fit the soil characteristics of interest. Here we found that slopes generated from resolutions smaller than 11m were poor predictors of soil characteristics. Both chapters are finished by proposing and evaluating a soil map. Proposed regressions beat SSURGO in all investigated properties. Furthermore, proposed maps consistently beat out uninformed smallest resolution derived maps.Chesapeake bay water quality managers are struggling to achieve targets for nitrogen loading. This is in part due to the widespread presence of legacy nitrogen. Legacy nitrogen is an emerging issue, and springs exporting high levels of nitrogen are not uncommon in northern Virginia. This thesis explores, in part, a novel concept of treating large loads of nitrogen exported from a spring with a bioreactor. Bioreactors are a young science that most typically pair carbon heavy subterranean receptacles to agricultural drainage. This provides a location for nitrogen fixing bacteria to consume nitrate/nitrite, turning these into inert nitrogen gas. A spring fed bioreactor is studied for 10 months, and bioreactor conditions including influent and effluent nitrogen concentrations, bioreactor flow, and temperature are collected. A model driven by first order reaction equations is found to be most accurate with inputs of temperature and bioreactor age. The resulting marginal effects of these inputs were consistent with previously reported studies. / Doctor of Philosophy / Centuries of industrialization have resulted in widespread human progress but have, at times, adversely impacted the environment. Constituents rely heavily on environmental services, such as clean air and water, to subsist. Environmental degradation has resulted in detrimental effects to public health, and remediation is currently economically viable. As such, there are strong incentives for researchers to understand environmental processes at a fundamental level. One such process is soil characteristic distribution. The distribution of soil characteristics, such as soil texture or organic matter, is especially important for agriculturalists, hydrologists and geotechnicians. Soil texture and organic matter distribution can affect crop yield, nitrogen export to surface waters, and structural stability of soils. Thus, accurate characterization of measured soil properties is paramount to multiple fields. The most typically used soil map is USDA‐NRCS Soil survey (commonly referred to as SSURGO). Currently, the SSURGO database is a poor predictor of soil characteristics. There is an opportunity to improve soil characteristic distribution using digital elevation models (DEMs). As DEMs become cheaper to develop, they are typically available in multiple resolutions and generation methods. In this research, several DEMs are used to better soil maps for watersheds in Southwest Virginia and Western Vermont. Both studies showed that DEMs can better distribute soils when compared to the current SSURGO maps. Additionally, we showed that the finest resolution dataset was not always best, and mixed resolution topographic wetness indices to be most advantageous for distributing soils.Another such process is remediation of surface waters from high loads of nitrogen and phosphorus. The Haber-Bosch method of producing nitrogen fertilizer is one of the most important human innovations in recent history. This method is likely responsible for the aversion of widespread famine in the early 1900s. However, residents of multiple river systems, including the Chesapeake Bay and the Mississippi River, are suffering from the adverse effects of widespread hypoxic/anoxic (with little/no oxygen, respectively) zones within water. These have partially been responsible for the decline of commercial ventures such as fisheries and tourism. These zones are caused by eutrophication, a process of unsustainable plant growth in the presence of nitrogen and phosphorus. Water quality managers typically target agricultural runoff and point source polluters when trying to eliminate anthropogenic nitrogen. However, legacy nitrogen (nitrogen stored in groundwater in excess of a year) has become an emerging concern for water quality. It is not uncommon for springs in karst areas to be contaminated with high concentrations of nitrogen. These springs present a point source that can be treated by an emerging technology: bioreactors. Bioreactors are subterranean, woodchip filled basins that provide a location for microbes to exchange water soluble nitrogen for inert nitrogen gas. The consistency in nitrogen loading and constant flow provide stability relative to more traditional bioreactor installations. Most typically, bioreactors are installed downstream of agricultural drainage systems, and influent flow and nitrogen load depend wholly on precipitation/irrigation and nitrogen application. In this thesis, a novel spring fed bioreactor is studied. Removal rates of nitrogen are quantified using a regression driven by reaction kinetics. The analysis showed bioreactor efficiency was intimately related to hydraulic residence time, nitrogen loading, bioreactor bed temperature, and bioreactor age. The spring fed bioreactor is found to be advantageous because of its consistency, and disadvantages because springs are colder and thus less efficient than typical irrigated runoff.
108

Prise en compte des dépendances entre données thématiques utilisateur et données topographiques lors d’un changement de niveau de détail / Taking into account the dependences between user thematic data and topographic data when the level of detail is changed

Jaara, Kusay 10 March 2015 (has links)
Avec l'importante disponibilité de données topographiques de référence, la création des données géographiques n'est plus réservée aux professionnels de l'information géographique. De plus en plus d'utilisateurs saisissent leurs propres données, que nous appelons données thématiques, en s'appuyant sur ces données de référence qui jouent alors le rôle de données support. Les données thématiques ainsi saisies font sens en tant que telles, mais surtout de par leurs relations avec les données topographiques. La non prise en compte des relations entre données thématiques et topographiques lors de traitements modifiant les unes ou les autres peut engendrer des incohérences, notamment pour les traitements liés au changement de niveau de détail. L'objectif de la thèse est de définir une méthodologie pour préserver la cohérence entre les données thématiques et topographiques lors d'un changement de niveau de détail. Nous nous concentrons sur l'adaptation des données thématiques suite à une modification des données topographiques, processus que nous appelons migration des données thématiques. Nous proposons d'abord un modèle pour la migration de données thématiques ponctuelles sur réseau composé de : (1) un modèle pour décrire le référencement des données thématiques sur les données topographiques par des relations spatiales (2) une méthode de relocalisation basée sur ces relations. L'approche consiste à identifier les relations finales attendues en fonction des relations initiales et des changements sur les données topographiques entre les états initial et final. La relocalisation est alors effectuée grâce à une méthode multicritère de manière à respecter au mieux les relations attendues. Une mise en œuvre est présentée sur des cas d'étude jouets et sur un cas réel fourni par un service de l'Etat gestionnaire de réseau routier. Nous discutons enfin l'extension du modèle proposé pour traiter la prise en compte des relations pour d'autres applications que la migration de données thématiques / With the large availability of reference topographic data, creating geographic data is not exclusive to experts of geographic information any more. More and more users rely on reference data to create their own data, hereafter called thematic data. Reference data then play the role of support for thematic data. Thematic data make sense by themselves, but even more by their relations with topographic data. Not taking into account the relations between thematic and topographic data during processes that modify the former or the latter may cause inconsistencies, especially for processes that are related to changing the level of detail. The objective of this thesis is to define a methodology to preserve the consistency between thematic and topographic when the level of detail is modified. This thesis focuses on the adaptation of thematic data after a modification of topographic data: we call this process thematic data migration. We first propose a model for the migration of punctual thematic data hosted by a network. This model is composed of: (1) a model to describe the referencing of thematic data on topographic data using spatial relations (2) a method to re-locate thematic data based on these relations. The approach consists in identifying the expected final relations according to the initial relations and the modifications of topographic data between the initial and the final state. The thematic data are then re-located using a multi-criteria method in order to satisfy, as much as possible, the expected relations. An implementation is presented on toy problems and on a real use case provided by a French public authority in charge of road network management. The extension of the proposed model to take into account the relations for other applications than thematic data migration is also discussed
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Dynamické vyšetření Moiré a Pedoscan u pacientů se skoliózou / Moiré and Pedoscan dynamic examinations of patients with scoliosis

Klímová, Michaela January 2015 (has links)
Scoliosis is the most common deformity of the spine affecting from 3 to 6% of human population. The thesis "Moiré and Pedoscan dynamic examinations of patients with scoliosis" summarizes the findings of kinesiology of the spine, pelvis and hip joints and ontogenesis of axial organ straightening. It also deals with the issue of idiopathic scoliosis, its incidence, etiology, classification, diagnosis, treatment options and applied physiotherapy methods. The paper emphasizes the influence of physiotherapy that forms an integral part of medical treatment. A great part of the thesis is devoted to the rasterstereographic and pedobarographic examination. The main purpose of this thesis was to detect and evaluate parameters assessing posture and movement of patients suffering from scoliosis and compare them with a control group. For this purpose, a pedobarographic system Diers pedoscan was used, which detected the distribution of compressive forces on the feet when walking and standing. It was also used a rasterstereographic system Diers formetric III 4D, which allowed for capturing photogrammetric recording of the spine and pelvis using a video-rasterstereography based on the Moiré topography. The study was carried out with a group of 22 females with idiopathic scoliosis up to 40ř according to Cobb aged...
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Prise en compte des dépendances entre données thématiques utilisateur et données topographiques lors d’un changement de niveau de détail / Taking into account the dependences between user thematic data and topographic data when the level of detail is changed

Jaara, Kusay 10 March 2015 (has links)
Avec l'importante disponibilité de données topographiques de référence, la création des données géographiques n'est plus réservée aux professionnels de l'information géographique. De plus en plus d'utilisateurs saisissent leurs propres données, que nous appelons données thématiques, en s'appuyant sur ces données de référence qui jouent alors le rôle de données support. Les données thématiques ainsi saisies font sens en tant que telles, mais surtout de par leurs relations avec les données topographiques. La non prise en compte des relations entre données thématiques et topographiques lors de traitements modifiant les unes ou les autres peut engendrer des incohérences, notamment pour les traitements liés au changement de niveau de détail. L'objectif de la thèse est de définir une méthodologie pour préserver la cohérence entre les données thématiques et topographiques lors d'un changement de niveau de détail. Nous nous concentrons sur l'adaptation des données thématiques suite à une modification des données topographiques, processus que nous appelons migration des données thématiques. Nous proposons d'abord un modèle pour la migration de données thématiques ponctuelles sur réseau composé de : (1) un modèle pour décrire le référencement des données thématiques sur les données topographiques par des relations spatiales (2) une méthode de relocalisation basée sur ces relations. L'approche consiste à identifier les relations finales attendues en fonction des relations initiales et des changements sur les données topographiques entre les états initial et final. La relocalisation est alors effectuée grâce à une méthode multicritère de manière à respecter au mieux les relations attendues. Une mise en œuvre est présentée sur des cas d'étude jouets et sur un cas réel fourni par un service de l'Etat gestionnaire de réseau routier. Nous discutons enfin l'extension du modèle proposé pour traiter la prise en compte des relations pour d'autres applications que la migration de données thématiques / With the large availability of reference topographic data, creating geographic data is not exclusive to experts of geographic information any more. More and more users rely on reference data to create their own data, hereafter called thematic data. Reference data then play the role of support for thematic data. Thematic data make sense by themselves, but even more by their relations with topographic data. Not taking into account the relations between thematic and topographic data during processes that modify the former or the latter may cause inconsistencies, especially for processes that are related to changing the level of detail. The objective of this thesis is to define a methodology to preserve the consistency between thematic and topographic when the level of detail is modified. This thesis focuses on the adaptation of thematic data after a modification of topographic data: we call this process thematic data migration. We first propose a model for the migration of punctual thematic data hosted by a network. This model is composed of: (1) a model to describe the referencing of thematic data on topographic data using spatial relations (2) a method to re-locate thematic data based on these relations. The approach consists in identifying the expected final relations according to the initial relations and the modifications of topographic data between the initial and the final state. The thematic data are then re-located using a multi-criteria method in order to satisfy, as much as possible, the expected relations. An implementation is presented on toy problems and on a real use case provided by a French public authority in charge of road network management. The extension of the proposed model to take into account the relations for other applications than thematic data migration is also discussed

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