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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.
1

Land Cover Change Analysis of the Mississippi Gulf Coast from 1975 to 2005 using Landsat MSS and TM Imagery

English, Amanda M. 20 May 2011 (has links)
The population, employment and housing units along the Gulf Coast of Mississippi have been increasing since the 1970s through the 2000s. In this study, an overall increasing trend in land cover was found in developed land area near interstates and highways along all three coastal counties. A strong positive correlation was observed in Hancock County between developed land and population and developed land and housing units. A strong negative correlation was observed between vegetation and housing units. Weak positive correlations were found in Harrison County between developed land and population, marsh and population, and marsh and housing units. A weak positive correlation was found in Jackson County between bare soil and population. Several study limitations such as unsupervised classification and misclassification are discussed to explain why a strong correlation was not found in Harrison and Jackson Counties.
2

Srovnání dat RÚIAN / ISKN a ZABAGED s důrazem na land use / land cover / Comparison of RÚIAN / ISKN and ZABAGED data with focus on land use / land cover

Štysová, Lucie January 2015 (has links)
The goal of this diploma thesis is to propose a proper method of comparison and quantification of differences in RÚIAN / ISKN and ZABAGED databases with respect to their specifics, while focusing on descriptive part of the data reflecting land use / land cover. This proposal is implemented using automated means of geographic information systems and the methodology is tested on sufficient number of appropriate areas. The theoretical part introduces with a possibility to compare datasets in general and with the characteristics of the both databases, with focus on their attribute part describing land use / land cover. The practical part consists of the design of comparison, methodology implementation description and testing of the whole design as well as testing of those individual components that influence the result of the comparison. Result of this thesis is a methodology and software (scripts) for comparison of RÚIAN / ISKN and ZABAGED databases.
3

Recul et persistance du paludisme en Union des Comores : une approche géographique pour déterminer l’importance des facteurs environnementaux et sociaux dans son maintien / Roll-back and persistence of malaria in the Union of the Comoros : a geographical approach to assess the importance on environmental and social factors in its maintenance

Artadji, Attoumane 08 February 2019 (has links)
Le paludisme a sévi dans l’archipel des Comores depuis 1925 où une grande épidémie s’est déclenchée à la Grande Comore. Ces îles ont offert des conditions favorables au développement des vecteurs responsables de la transmission du paludisme (Anopheles gambiae et Anopheles funestus) avec un climat tropical humide, une forte densité hydrographique, un environnement forestier et marécageux et la construction de citernes de collecte d’eau de pluie dans les habitations. Cette maladie est devenue endémique stable depuis les années 70 et un problème de santé publique majeur jusqu’aux années 2000. Dès la fin des années 90, le gouvernement comorien a décidé de mettre en place une stratégie de lutte contre le paludisme par la lutte anti-vectorielle et la protection de la population contre les piqûres des moustiques. Ces vingt dernières années, ces actions de lutte contre le paludisme se sont intensifiées et, pour la première fois, un traitement de masse à base d’Artequick a été réalisé à Mohéli (2007-2009), à Anjouan (2012-2013) et à la Grande Comore (2013). Depuis, un recul spectaculaire du paludisme a été observé sur l’ensemble des îles, car Mohéli et Anjouan sont entrées en phase de pré-élimination et la Grande Comore en phase de contrôle. Cette thèse décrit, dans la première partie, l’évolution spatiale et temporelle du paludisme avant et après le traitement de masse pour appréhender l’impact des différentes actions de lutte. Une cartographie de la prévalence en milieu hospitalier et de l’incidence du paludisme à l’échelle des districts sanitaires et des villages montre son recul à Anjouan et Mohéli et son maintien à la Grande Comore. Les tests d’autocorrélation spatiale ont révélé une similitude de la transmission du paludisme entre des localités proches, qui forment des clusters à la Grande Comore. Nous avons démontré, dans la deuxième partie, qu’il existe bel et bien une influence des facteurs environnementaux sur la transmission du paludisme bien que les actions de lutte ont plus de poids. À l’échelle des districts sanitaires, des modèles de régressions linéaires simple et multiple ont été établis entre l’incidence du paludisme et les caractéristiques de l’occupation du sol des îles et les indicateurs paysagers à l’échelle des villages de la Grande Comore. Une enquête sur les connaissances, les pratiques et les vulnérabilités des populations a été menée sur 1288 ménages de l’Union des Comores pour appréhender les facteurs de vulnérabilité favorables à la transmission du paludisme. Au-delà de la présence des citernes dans les ménages, le lieu de dépôt de déchets ménagers favoriserait son maintien à la Grande Comore. L’enquête a révélé que plusieurs ménages de la grande île n’avaient pas pris le traitement de masse de 2013. Cette thèse permet de mieux comprendre les aspects humains et environnementaux du maintien du paludisme et vise ainsi à mieux cibler les futures actions de lutte. / Malaria has been present in the Comoros archipelago since 1925, when a major epidemic was first recorded in Grande Comore. The islands have been favourable to the development of vectors causing malaria transmission (Anopheles gambiae and Anopheles funestus) due to the high tropical rainfall, high hydrographic density, the suitable environment with forests and wetlands, as well as the construction of water reservoirs in households. This disease has been endemic since the 1970s and a major public health problem until the 2000s. From the end of the 1990s, the Comorian government has decided to implement a strategy to control malaria by anti-malaria vector control and population protection against mosquito bites. In the last twenty years, malaria control efforts have been intensified and for a first time, mass treatment with Artequick has been carried out in Mohéli (2007-2009), Anjouan (2012-2013) and Grande Comore (2013). There has since been a dramatic decline in malaria on all the islands, as Mohéli and Anjouan have entered a pre-elimination phase and Grande Comore is in the control phase. In the first part, this thesis describes the spatial and temporal dynamics of malaria before and after mass treatment in order to understand the impact of different control actions. A mapping of hospital prevalence and incidence of malaria at the district and village levels shows its decline in Anjouan and Mohéli and its persistence in Grande Comore. Spatial autocorrelation tests have revealed a similarity in malaria transmission between neighbouring localities that are forming clusters in Grande Comore. In the second part, it was demonstrated that environmental factors have an influence on malaria transmission, despite the greater importance of control actions. At the district level, simple and multiple linear regression models have been established between the incidence of malaria and land cover / land use patterns of islands and landscape indicators at the village level in Grande Comore. A survey on people's knowledge, practices and vulnerabilities was conducted among 1,288 households in the Union of the Comoros to assess factors of vulnerability that contribute to malaria transmission. Beyond having water reservoirs in households, the waste disposal location would also have an impact on malaria in Grande Comore. The survey revealed that several households on the large island did not take the 2013 mass treatment. This thesis provides a better understanding of the human and environmental aspects of malaria maintenance and thus aims to better target future control actions.
4

Modeling the effect of land cover land use change on estuarine environmental flows

Sahoo, Debabrata 15 May 2009 (has links)
Environmental flows are important to maintain the ecological integrity of the estuary. In a watershed, it is influenced by land use land cover (LULC) change, climate variability, and water regulations. San Antonio, Texas, the 8th largest city in the US, is likely to affect environmental flows to the San Antonio Bay/Guadalupe Estuary, due to rapid urbanization. Time series analysis was conducted at several stream gauging stations to assess trends in hydrologic variables. A bootstrapping method was employed to estimate the critical value for global significance. Results suggested a greater number of trends are observed than are expected to occur by chance. Stream gauging stations present in lower half of the watershed experienced increasing trend, whereas upper half experienced decreasing trends. A similar spatial pattern was not observed for rainfall. Winter season observed maximum number of trends. Wavelet analysis on hydrologic variables, suggested presence of multi-scale temporal variability; dominant frequencies in 10 to 15 year scale was observed in some of the hydrologic variables, with a decadal cycle. Dominant frequencies were also observed in 17 to 23 year scale with repeatability in 20 to 30 years. It is therefore important to understand various ecological processes that are dominant in this scale and quantify possible linkages among them. Genetic algorithm (GA) was used for calibration of the Hydrologic Simulation Program in FORTRAN (HSPF) model. Although, GA is computationally demanding, it is better than manual calibration. Parameter values obtained for the calibrated model had physical representation and were well within the ranges suggested in the literature. Information from LANDSAT images for the years 1987, 1999, and 2003 were introduced to HSPF to quantify the impact of LULC change on environmental flows. Modeling studies indicated, with increase in impervious surface, peak flows increased over the years. Wavelet analysis pointed, that urbanization also impacted storage. Modeling studies quantified, on average about 50% of variability in freshwater inflows could be attributed to variation in precipitation, and approximately 10% of variation in freshwater inflows could be attributed to LULC change. This study will help ecologist, engineers, scientist, and politicians in policy making pertinent to water resources management.
5

Evapotranspiration Estimation from MOD16 MODIS Data Product and Compared with Flux Tower Observations of Toledo

Rahman, Md Tajminur, Rahman January 2017 (has links)
No description available.
6

Geospatial analysis of canine leptospirosis risk factors in the central Great Plains region

Raghavan, Ram January 1900 (has links)
Doctor of Philosophy / Department of Diagnostic Medicine/Pathobiology / K.R. Harkin / T.G. Nagaraja / Associations of land cover/land use, socio-economic and housing, and hydrological and soil-hydrological variables were evaluated retrospectively as potential risk factors for canine leptospirosis in Kansas and Nebraska using Geographic Information Systems (GIS). The sample included 94 dogs positive for leptospirosis based on a positive polymerase chain reaction test for leptospires in urine, isolation of leptospires on urine culture, a single reciprocal serum titer of 12,800 or greater, or a four-fold rise in reciprocal serum titers over a 2 to 4 week period; and 185 dogs negative for leptospirosis based on a negative polymerase chain reaction test and reciprocal serum titers less than 400. Publicly available geographic datasets representing land cover/land use, socio-economic and housing characteristics, and hydrologic and soil hydrologic themes were analyzed along with geocoded addresses of case/control locations in GIS. Among different land cover/land use variables evaluated, urban areas (high and medium intensity urban areas and urban areas in general) and evergreen forests and forest/woodlands in general were significant risk factors. Among socio-economic and demographic determinants evaluated, houses lacking complete plumbing facilities, poverty status by age (18-64), and living within 2500 meters of a university/college or parks/forests were significant risk factors. Proximity to water features, hydrologic density and frequently flooded areas were identified as significant risk factors for canine leptospirosis among hydrologic and soil-hydrologic variables. Pet owners whose dogs live in such areas or under these circumstances should consider vaccination to prevent canine leptospirosis.
7

Ontologie jako nástroj pro návrhy datových modelů vybraných témat příloh směrnice INSPIRE / Ontologies as an instrument for a design of data models of selected themes of the INSPIRE directive

Čerba, Otakar January 2012 (has links)
It turns out that for most users of spatial data presents a harmonization of data (as an elimination of heterogeneity) as the greatest problem - a transformation their own data sets to the data specifications produced by the INSPIRE Directive so as not to limit current processes processing, management, sharing and presentation of data. Therefore, they need the widest possible description of spatial data, because it will only eliminate the problems of heterogeneity. The author of this Ph.D. thesis dealt with the opportunities which ontologies bring to the process of data modelling. The aim was to describe using ontologies the selected part (classification systems) of data models of spatial data themes "Land Cover" and "Land Use" which are defined in Annexes II and III of the INSPIRE directive. Developed ontologies serve as a source of information on classification systems. Their evaluation (so-called reasoning) will provide new information (relationships between taxonomy elements) that play an important role in the transformation process of classification systems as part of the harmonization of spatial data. Creating of ontologies consisted of three main steps - selection of appropriate methodology, development of a basic ontology structure and iterative process of populating and specification of...
8

Využití krajiny (Land use) ve vybrané lokalitě / Land use GIS in a selected municipality

Sekanina, Michal January 2014 (has links)
The thesis content study of land use in municipality Lelekovice and its connection with software for geographic information system. It describes processing data especially historical cadastre maps, archival aerial imagery and orthophotos which were used for analyzing of this area. Analysis were performed in software ArcGIS. Appendixes of thesis are graphs and visualization of development of study area.
9

Modeling Land-Cover/Land-Use Change: A Case Study of a Dynamic Agricultural Landscape in An Giang and Dong Thap, Vietnam

Haynes, Keelin 31 July 2020 (has links)
No description available.
10

Zhodnocení vybraných datových zdrojů využití krajiny / Evaluation of the selected data sources of land use/land cover

Míček, Ondřej January 2017 (has links)
The topic of this study is to evaluate data sources from the perspective of the information about landscape they provide to their users. The aim is comparison of thematic content of Urban Atlas database and data from Czech cadastre of real estate in Prague metropolitan region between years 2006 and 2012 with focus at meaning of classification systems used by both datasets. The data are processed by evaluation of thematic similarity and statistical tools which quantify similarity between researched data. Results are further verified by using validation data. Important results are visualized by charts, tables and maps. The areas with high degree of dissimilarity were found using chosen methods and their thematic characteristics were further examined as well as their major causes. It was proved that differences between both datasets are significant and they share certain characteristics. It was also proved that cadastral data are to high extent out-of-date. Keywords Urban Atlas, cadastre of real estate, land use, land cover, Prague

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