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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.
11

Geoprocessamento e sensoriamento remoto como ferramentas na gestão ambiental de Unidades de Conservação: o caso da Área de Proteção Ambiental (APA) do Capivari-Monos, São Paulo-SP. / Geographical Information System and Remote Sensing as tools for conservation units environmental management: Capivari-Monos Environmental Protection Area case (São Paulo-SP).

Jacintho, Luiz Roberto de Campos 20 March 2003 (has links)
Um quadro diagnóstico da Área de proteção Ambiental(APA) do Capivari Monos foi elaborado com informações produzidas através da aplicação de geoprocessamento e sensoriamento remoto. Essa Unidade de Conservação se localiza no extremo sul do município de São Paulo, onde ainda existem importantes fragmentos de Mata Atlântica e mananciais hídricos estratégicos para a Região Metropolitana de São Paulo . Um Mapa Geomorfológico foi produzido com o apoio de um Modelo Numérico de Terreno. Com a aplicação de Álgebra de Mapas, foram integrados os dados sobre Geotecnia e Geomorfologia e um mapa de Fragilidade do Meio Físico foi elaborado. As condições de hidrografia e relevo apontaram indícios de movimentação tectônica recente na região. Imagens dos Satélites Landsat-5 e Landsat-7 foram comparadas, com o emprego de técnicas de detecção de mudanças, para a quantificação do desmatamento no período entre 1991 e 2000. As imagens do satélite Landsat-7 foram classificadas, através do método supervisionado por regiões, para produção de um mapa temático de Uso do Solo e Cobertura Vegetal. Os resultados foram quantificados por sub-bacias hidrográficas, compondo um quadro comparativo que se destina a subsidiar a gestão ambiental da APA. Esses resultados mostram que o crescimento da ocupação urbana se concentra na bacia da Billings, principalmente na subbacia da Cratera de Colônia, onde a fragilidade do meio físico foi considerada muito alta. / Through the application of Geographical Information System and Remote Sensing it was elaborated a chart diagnosis for Capivari-Monos Environmental Protection Area. This Conservation Unit is located in the south end of São Paulo city where important Atlantic Forest fragments and strategic water spring still exist. With the support of a Digital Terrain Model it was produced a Geomorphologic map. Applying Map Algebra the data on Geothecnics and Geomorphorlogy had been integrated for mapping the fragility of physical environment. Relief and hidrography conditions pointed indications of neotectonic movements in this region. Employing change detection techniques in Landsat-7 images the deforestation between 1991 and 2000 was evaluated. A land use and land cover map was produced trough Landsat-7 image classification ( supervised per region method). The results show that the urban growth concentrates on the basin of Billings, mainly at the Cratera de Colônia sub-basin where the fragility regarding to phisical environment was considered very high.
12

Caracterização geotécnica do subsolo de Curitiba para o planejamento de ocupação do espaço subterrâneo / Geotechnical characterisation of Curitiba city, southern Brazil, for planning of underground space

Talamini Neto, Edmundo 11 January 2002 (has links)
Devido ao seu crescimento acelerado o município de Curitiba deverá, em breve, ter seu espaço subterrâneo ocupado com maior intensidade. Este processo deve ser devidamente planejado, levando-se em conta as propriedades geotécnicas do subsolo. Assim, buscou-se desenvolver e aplicar um método de caracterização geotécnica do meio urbano para fins de planejamento do espaço subterrâneo. O trabalho consistiu no mapeamento tridimensional das principais unidades geotécnicas e na sua caracterização em termos de adequação para obras subterrâneas. Para tanto, inicialmente, reuniu-se dados geotécnicos existentes (sondagens, poços, mapas topográficos), e levantou-se pontos em campo. A partir do mapa topográfico gerou-se imagens artificiais do terreno, que foram reunidas aos demais dados em um sistema de informações geográficas (SIG). Este processo permitiu a elaboração de um mapa geológico simplificado. Os dados armazenados no sistema (SPT, profundidades das unidades geológicas, entre outros) passaram por uma filtragem, sendo exportados para a realização de análises geoestatísticas, interpolações e geração de cartas de isovalores. Grades regulares com valores interpolados foram então inseridas no SIG, constituindo-se um modelo geotécnico digital tridimensional que permite a navegação virtual entre unidades geotécnicas. Através de classificação geomecânica determinou-se as condições de suporte e estabilidade para possíveis túneis em rochas do município. No caso dos solos realizaram-se análises limite considerando informações de campo e ensaios SPT. Integrando- e, em um único documento, cartas de profundidade das unidades geotécnicas, o mapa geológico simplificado e informações construtivas para túneis, gerou-se um mapa orientativo para a construção de obras subterrâneas no município de Curitiba. Este mapa pode ser diretamente aplicado no planejamento de ocupação do subterrâneo. / Due to its fast population increase, the city of Curitiba will soon have to use its underground space. However, underground space use should be previously planned, taking geotechnical information into consideration. Therefore, the present research is intended to develop and apply an urban geotechnical characterisation method for underground space planning. The work consisted of a 3D mapping of main geotechnical units and determination of their suitability for underground constructions. At first, existing geotechnical data, such as borehole logs, well logs and topographic maps, have been collected and stored. Field studies were carried out subsequently. Digital terrain models have been obtained from topographic maps, and integrated with the other data in a geographical information system (GIS). This process allowed for the production of a simplified geological map. The stored data have been filtered and exported for the development of geostatistical analysis, interpolations and contour maps. Interpolated grids were then reinserted in the GIS software, where a 3D digital geotechnical model has been produced, permitting virtual navigation through soil layers. Tunnel stability and support design evaluations have been performed by means of rock mass classifications. For soil tunnel stability and support assessments, field studies and N-SPT correlations have been used along with limit analysis. A decision support geotechnical map for underground constructions has been obtained by representing, in a single document: the simplified geological map, geotechnical unit depth contour charts, tunnel stability and support analysis results. This decision support map may be directly applied for underground space planning activities.
13

Aplicação de sensoriamento remoto e geoprocessamento para analisar a distribuição da malária na região do reservatório de Tucuruí-PA / Remote sensing and geoprocessing to analyze malaria distribution at the UHE Tucuruí-Pará region

Vasconcelos, Cíntia Honório 15 April 2004 (has links)
A malária é a mais importante doença tropical do mundo. Em muitos países, especialmente no continente africano, causa grandes prejuízos com custos médicos e dias de trabalho perdidos. O risco de contrair malária está relacionado a alterações ambientais causadas por atividades como construções de estradas, projetos de mineração, agricultura e irrigação, particularmente em áreas da região amazônica e sudeste asiático. Entre outras causas da expansão desta endemia no mundo, pode-se incluir as mudanças climáticas, desintegração dos serviços de saúde e movimentos migratórios. Em áreas onde a malária é endêmica, o monitoramento das larvas e de populações de mosquitos adultos é de grande importância para o controle da doença. Novas ferramentas são necessárias para este processo, dentre os quais, as técnicas de sensoriamento remoto e os sistemas de informação geográfica (SIG). Essas técnicas têm reduzido custos e tempo nas pesquisas epidemiológicas, pois são usadas em escala regional para identificar tipos de vegetação, alterações ambientais que podem favorecer a proliferação de vetores da doença. Dada à gravidade da malária na região amazônica, este trabalho tem por objetivo entender como os padrões de distribuição espacial dos casos de malária na região da Usina Hidrelétrica de Tucuruí-PA se relacionam com os padrões de ocupação da terra, induzidos por sua implantação. Foi utilizado um conjunto de dados que incluem imagens TM-LANDSAT5 e SAR-RADARSAT para o levantamento de uso da terra os municípios de Tucuruí, Novo Repartimento e Jacundá e também para monitorar a variação sazonal do reservatório da UHE de Tucurui, além de uma série histórica de dados de malária do período compreendido entre 1992 a 2001. Esses dados foram integrados e analisados por meio do software SPRING 3.6. Foi constatado que os municípios de Novo Repartimento e Tucuruí, por possuírem grandes áreas de contato com o reservatório, apresentaram maiores problemas com a malária e que a variação temporal da doença, nesta região, está relacionada com o ciclo do reservatório, com a precipitação e com a dinâmica da população. / Malaria is the most important tropical disease in the world. In many countries, specially in the African continent, malaria is responsible for huge economical losses with medical bills and absenteeism. Malaria risk relates to environmental change derived from road construction, mining activities, agriculture and irrigation mainly in forested areas such as Amazon region and southern Asia. Among the causes explaining the spread of this endemic disease in the world, one can include climatic changes, healthy service breakdown and migration. At malaria endemic areas, larva and mosquito monitoring is highly important for disease control. New tools however are needed such as remote sensing and geographical information system in epidemic areas. These techniques have been responsible for reducing the time and cost of epidemiological researches, since they are used in a regional scale for assessing environmental disturbance apt to spreading of malaria vectors. Due to the threat of malaria in the Amazon region, this research aims to understand the relationship between land use changes induced by UHE-Tucuruí construction and the spatial distribution of malaria incidence in the region. LANDSAT5-TM and RADARSAT-SAR images were used respectively for land use mapping at Tucuruí, Novo Repartimento and Jacundá municipality and for monitoring the seasonal variation of UHE Tucuruí reservoir flooded area. A historic series of malaria data acquired for the National Health Foundation between 1992 and 2001 was also used. These data were integrated and analyzed with the aid of the SPRING 3.6 software. It was determined that Novo Repartimento and Tucuruí with large areas bounded by the reservoir are more prone to malaria incidence and that the time change in the disease in this region is related to the hydrology and reservoir operation, as well as with the precipitation and population dynamic.
14

Multiple Hazards and Community Vulnerability in Hillsborough County, Florida

Albury, Keith Allen 14 July 2004 (has links)
Hillsborough County, Florida is subject to a variety of natural and technological hazards, which have the potential to threaten both the population and the built environment. This research focuses on several natural hazards (coastal flooding, sink hole, and hurricane) and technological hazards (toxic transportation spills and toxic release from fixed storage facilities) and the population that is potentially exposed to these hazards. Social vulnerability for this population was determined using racial composition, gender, age and household rental/ownership status. Both social vulnerability and exposure to hazardous conditions occur as a continuum across geographical space. The determination of who is exposed; the extent of exposure; and the hazardousness of their environment; requires converting this continuum into discreet values. There is little agreement on how this should be accomplished. The goal of this project is to improve on this situation by developing a multiple hazard map and a social vulnerability map using the best available data with a focus on data integration. The resulting maps were used to determine the extent that the community of Hillsborough County is exposed to hazardous conditions and the social vulnerability of that exposed community. The impact of hazard analysis is dependant on the creation of the hazard map. The hazard map can be affected by application of weighting factors to the individual or groups of hazards. Weighted linear combinations were used to examine how the exposed population changes when different hazard models are used. A technique of cumulative frequency mapping was used to examine how the composition of the exposed population changed as the hazard scores increased. This was useful in visualizing that different vulnerable communities were not exposed to hazards equally. This technique will be useful for future vulnerability/hazard assessments. The results of this research show that the most vulnerable populations in Hillsborough County, Florida are not exposed to the most extreme hazards. Instead the preponderance of the population is moderately vulnerable and is exposed to moderate hazards. It is important to focus on this population to help prepare for and respond to hazardous events and to work toward diminishing their social vulnerability.
15

Comparison of fuzzy and crisp analytic hierarchy process (AHP) methods for spatial multicriteria decision analysis in GIS

Kordi, Maryam January 2008 (has links)
<p>There are a number of decision making problems in which Geographical Information System (GIS) has employed to organize and facilitate the procedure of analyzing the problem. These GIS-based decision problems which typically include a number of different criteria and alternatives are generally analyzed by Multicriteria Decision Analysis (MCDA).Different locations within a geographical area represent the alternatives by which the overall goal of the project is achieved. The quality of achieving the goal is evaluated by a set of criteria which should be considered in the work. Analytic Hierarchy Process (AHP) which is a powerful method of MCDA generally can organize spatial problems and decides which alternatives are most suitable for the defined problems. However due to some intrinsic uncertainty in the method, a number of authors suggest fuzzifying the method while others are against fuzzification of the AHP.</p><p>The debate over fuzzifying AHP is going on and attempt for finding that was mostly in theory, and little, if any; practical comparison between the AHP and fuzzified AHP has done. This work presents a practical comparison of AHP and fuzzy AHP in a GIS-based problem, case study, for locating a dam in Costa Rica, considering different criteria. In order to perform the AHP and fuzzy AHP in the GIS-based problem and calculating weights of the criteria by the methods, some computer codes have written and developed in MATLAB.</p><p>The comparisons between the AHP and fuzzy AHP methods are done on result weights and on the result final maps. The comparison between the weights is repeated on different levels of uncertainty in fuzzy AHP then all the results are compared with the result of AHP method. Also this study for checking the effect of fuzzification on results is suggested Chi-Square test as a suitable tool.</p><p>Comparisons between the resulting weights of the AHP and fuzzy AHP methods show some differences between the methods. Furthermore, the Chi-Square test shows that the higher level of uncertainty in the fuzzy AHP, the greater the difference in results between the AHP and fuzzy AHP methods.</p>
16

Dynamic Data Extraction and Data Visualization with Application to the Kentucky Mesonet

Paidipally, Anoop Rao 01 May 2012 (has links)
There is a need to integrate large-scale database, high-performance computing engines and geographical information system technologies into a user-friendly web interface as a platform for data visualization and customized statistical analysis. We present some concepts and design ideas regarding dynamic data storage and extraction by making use of open-source computing and mapping technologies. We implemented our methods to the Kentucky Mesonet automated weather mapping workflow. The main components of the work flow includes a web based interface, a robust database and computing infrastructure designed for both general users and power users such as modelers and researchers.
17

防災担当者の技術力向上のための耐震設計の共通化と地震応答の統合的可視化

堀, 宗朗, HORI, Muneo, 井上, 純哉, INOUE, Junya, 市村, 強, ICHIMURA, Tsuyoshi, 中村, 光, NAKAMURA, Hikaru, 若井, 明彦, WAKAI, Akihiko, 海老澤, 健正, EBISAWA, Takemasa, 山口, 直也, YAMAGUCHI, Naoya 07 1900 (has links)
No description available.
18

Comparison of fuzzy and crisp analytic hierarchy process (AHP) methods for spatial multicriteria decision analysis in GIS

Kordi, Maryam January 2008 (has links)
There are a number of decision making problems in which Geographical Information System (GIS) has employed to organize and facilitate the procedure of analyzing the problem. These GIS-based decision problems which typically include a number of different criteria and alternatives are generally analyzed by Multicriteria Decision Analysis (MCDA).Different locations within a geographical area represent the alternatives by which the overall goal of the project is achieved. The quality of achieving the goal is evaluated by a set of criteria which should be considered in the work. Analytic Hierarchy Process (AHP) which is a powerful method of MCDA generally can organize spatial problems and decides which alternatives are most suitable for the defined problems. However due to some intrinsic uncertainty in the method, a number of authors suggest fuzzifying the method while others are against fuzzification of the AHP. The debate over fuzzifying AHP is going on and attempt for finding that was mostly in theory, and little, if any; practical comparison between the AHP and fuzzified AHP has done. This work presents a practical comparison of AHP and fuzzy AHP in a GIS-based problem, case study, for locating a dam in Costa Rica, considering different criteria. In order to perform the AHP and fuzzy AHP in the GIS-based problem and calculating weights of the criteria by the methods, some computer codes have written and developed in MATLAB. The comparisons between the AHP and fuzzy AHP methods are done on result weights and on the result final maps. The comparison between the weights is repeated on different levels of uncertainty in fuzzy AHP then all the results are compared with the result of AHP method. Also this study for checking the effect of fuzzification on results is suggested Chi-Square test as a suitable tool. Comparisons between the resulting weights of the AHP and fuzzy AHP methods show some differences between the methods. Furthermore, the Chi-Square test shows that the higher level of uncertainty in the fuzzy AHP, the greater the difference in results between the AHP and fuzzy AHP methods.
19

Predicting Wildfires and Measuring their Impacts: Case Studies in British Columbia

Xu, Zhen 29 April 2014 (has links)
As the most destructive forest disturbance in British Columbia, wildfire becomes more worrisome for increasing uncertainty due to climate change. The current study investigates the potential to predict wildfire occurrence using climate indexes and quantify its marginal prices for property values at the municipal level, so as to provide a quantitative indicator for decision making in regard to influences of wildfire occurrence in the near future. First, significant correlations between monthly temperature and precipitation and large fire occurrence with distinctions in terms of distances to municipalities are proved by statistical analysis. Monthly wildfire occurrence are then statistically estimated with the four-month lags of the El Niño index and predicted using count models with regional differences. At last, the hedonic pricing model shows distance based positive impact of fire frequency and negative impact of fire size in neighbouring areas on property values. / Graduate / 0366 / 0478 / 0463 / zach_xu@hotmail.com
20

Predicting Wildfires and Measuring their Impacts: Case Studies in British Columbia

Xu, Zhen 29 April 2014 (has links)
As the most destructive forest disturbance in British Columbia, wildfire becomes more worrisome for increasing uncertainty due to climate change. The current study investigates the potential to predict wildfire occurrence using climate indexes and quantify its marginal prices for property values at the municipal level, so as to provide a quantitative indicator for decision making in regard to influences of wildfire occurrence in the near future. First, significant correlations between monthly temperature and precipitation and large fire occurrence with distinctions in terms of distances to municipalities are proved by statistical analysis. Monthly wildfire occurrence are then statistically estimated with the four-month lags of the El Niño index and predicted using count models with regional differences. At last, the hedonic pricing model shows distance based positive impact of fire frequency and negative impact of fire size in neighbouring areas on property values. / Graduate / 0366 / 0478 / 0463 / zach_xu@hotmail.com

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