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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.
111

Fragmentação florestal e prioridades para a conservação da biodiversidade / Forest fragmentation and biodiversity conservation priorities

José Marcelo Domingues Torezan 06 March 2004 (has links)
Um modelo dedicado ao planejamento da conservação e restauração de habitats deve incluir informações estratégicas para assegurar a eficácia e de fácil obtenção, para assegurar a agilidade necessária. Planos e estratégias para conservação usualmente são complexos e demandam informações detalhadas, difíceis de se obter, como inventários biológicos e certos tipos de mapeamento, o que traz limitações em termos de disponibilidade, qualidade e custo das informações. Assim, procurou-se testar a eficiência de métodos simples para a seleção, em escala local, de áreas prioritárias para conservação de habitats fortemente fragmentados e reduzidos, uma situação comum no sul do Brasil, usando dados de imagens LANDSAT e planos de informações disponíveis em mapeamentos comuns, e trabalho de campo. Inicialmente analisou-se a estrutura da paisagem e o padrão de fragmentação em parte da região norte do estado do Paraná, e testar se tamanho e forma são adequados para selecionar os fragmentos florestais mais importantes para a conservação, ou seja, as que contribuem para manter maior quantidade e melhor qualidade de habitats, bem como tenham maior impacto (positivo) na conectividade e em outras variáveis da paisagem. Os resultados mostram que a floresta madura cobre cerca de 3% da paisagem, e a cobertura florestal total atinge perto de 8%, consistindo principalmente de pequenos fragmentos (82% tem entre 1 e 10 ha). Fragmentos grandes (>100 ha) são apenas 1,4% dos remanescentes, mas somam 34% da área de floresta. Apesar de estarem sujeitos a efeitos de borda em toda ou quase toda a sua área, fragmentos pequenos mostraram ter um papel importante na conectividade da paisagem. Numa área maior, foi feita uma pré-seleção de áreas com potencial para estabelecimento de redes de conservação. A pré-seleção procurou responder às seguintes perguntas: 1-Quais são os sítios com maior potencial para a conservação da biodiversidade? 2-Quais são os sítios sob maior risco para objetivos de conservação? e 3-Quais sítios têm melhores oportunidades para o estabelecimento de zonas de conservação de uso múltiplo? Foi identificado um conjunto de 11 fragmentos pertencendo a 5 sub-regiões, sofrendo variados graus de pressão antrópica. Adicionalmente, usando medidas simples de estrutura da paisagem, relacionadas com tamanho, forma e conectividade dos fragmentos, procurou-se identificar tipos estruturais de fragmentos, como uma forma alternativa para auxiliar o estabelecimento de prioridades para conservação a partir do seu papel, efetivo ou potencial, na paisagem. Foram identificados 5 tipos de fragmentos, pequenos (ilhotas isoladas, trampolins), médios (núcleos auxiliares e corredores) e grandes (núcleos principais), que podem ser usados para subsidiar estratégias de conservação. Utilizando informações sobre a estrutura da paisagem, hidrografia e legislação ambiental, propõe-se aqui uma estratégia de conservação para o complexo das bacias dos ribeirões Apertados-Três Bocas (CATB), ordenando atividades de restauração e conservação de fragmentos florestais, criação e expansão de unidades de conservação, além da proposição de formas de uso do solo compatíveis com o entorno de unidades de conservação. / Models dedicated to habitat conservation, management and restoration planning must include information both strategic, to ensure effectiveness, and of easy collection, to ensure agility. Plans and strategies for conservation usually are complex and demand detailed data, such as biological inventories and fine scale mapping, which limits work due to information availability, quality and cost. Hence, as a first approach, we tested the efficacy of a simple methods for selection, in local scale, of conservation sites in strongly fragmented landscapes, a common situation in southern Brazil, using LANDSAT data, common mapping data layers, and fieldwork. First, we analyzed landscape structure and fragmentation patterns in the northern portion of Paraná state, looking for the suitability of using size and shape of forest fragments for selection of most important sites for conservation, i.e. fragments that contribute to encompass large and of best quality forest areas, as well have higher positive impact on connectivity and overall landscape structure. Results show that mature forest cover near 3% of landscape area, with total forest cover reaching near 8%, mostly small fragments (82% between 1 and 10 ha). Large fragments (>100 ha) are only 1,4% of fragment number, but encompass 34% of forest area. In spite of suffering of edge effects in almost or all their area, small fragments showed an important role in landscape connectivity. In a larger area we did a pre-selection of suitable areas for establishing conservation networks. Such pre-selection were intended to answer the following questions: 1-What sites have higher biodiversity conservation potential? 2-What sites have higher threats to conservation goals? and 3-What sites have better opportunity to establish multiple-use conservation zones? A set of 11 fragments over 500 ha were selected, being part of 5 conservation sites, of varying degree of development pressure. Using simple landscape structure measures, such as size, shape and connectivity, we tried to identify structural types of habitat fragments, as an alternative way of fragment prioritizing. We identified 5 fragment types, small (stepping-stones and small isolated islands), mid-sized (auxiliary nuclei and corridors) and large (main nuclei), that can be used for landscape conservation strategies. Finally, using information about landscape structure, hidrography, human impacts and environmental legislation, we proposed a integrated conservation strategy for the Apertados-Três Bocas river basin complex (CATB), near Londrina city, encompassing ordination of restoration activities, establishment of new conservation units and expansion of existing ones, as well as proposing land uses compatible with conservation goals.
112

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

Edmundo Talamini Neto 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.
113

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).

Luiz Roberto de Campos Jacintho 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.
114

Statistical Analysis of Team Training in Emergency Management Simulator System

Jahangir, Muhammad Nasir, Fahadullah, Muhammad January 2009 (has links)
In this thesis work, we compare the results obtained from two kinds of teams forming a hierarchical organization participating in a fire fighting simulation environment called as C3Fire. First kind of teams used paper-based maps for spatial reasoning of the command tool while the other kind of teams has GIS based maps with full access to positioning data of the fire fighting units as well as sensor information about fire break. The collected data was from 11 teams of each kind having 6 members in each team making a total of 132 participants belonging to different parts of the world. We made a statistical analysis on the data with help of T-Test statistical medhod and a tool is designed by using Java as programming language and PostgreSQL database for importing data from log files and then applying statistical T-Test method on the fetching data from log files.The results are stored in database as well as excel files. Then a comparison is done to analyze the unit performance, communication and efficiency of both kinds of teams.
115

Spatial analysis of open space in the quaternary catchment of the Lourens river

Raitt, Gwendolyn Rose January 2011 (has links)
Magister Scientiae (Biodiversity and Conservation Biology) / This thesis looks at aspects relating to vegetated open space in the quaternary catchment of the Lourens River, Cape Town, South Africa in 2005 and at GoogleEarth as a source of imagery for research. The research questions were: “Is GoogleEarth a suitable source of imagery for spatial analysis of landscapes?”; “What was the potential access (proximity) to vegetated open space of at least 900 m2 in the Lourens River quaternary catchment in 2005?”; “How many vegetated open spaces with an area of at least 900 m2 were present in the Lourens River quaternary catchment in 2005?” and “What spaces within the urban edge in the Lourens River quaternary catchment can be said to have some protection from development?” Open space has multiple benefits for humans in terms of health and social interaction.In urban areas, it is also important for biodiversity conservation. In Cape Town, this is critical since the city has critically endangered national vegetation types that only occur within its boundaries and 319 IUCN Red List species within its boundaries.Proximity does not reflect use of open space which is affected by the size of the open space, quality of the open space, neighbourhood attributes and individual and collective perceptions of the open space. Quality of vegetated open space is dependent on its facilities and maintenance which are largely determined by its management. In Cape Town, open space management is mainly mowing/brush cutting all spaces which has a negative impact on biodiversity retention. Mowing is continued because of popular demand so action needs to be taken to change popular perceptions.Google Earth is readily available and widely used. It is used for research in diverse disciplines. Local Internet connection problems complicated this study. Alignment and projection problems were encountered in this study. Thus Google Earth geospatial issues make it a poor choice of imagery source for large scale spatial analysis of landscapes.Open space was digitized in Google Earth and transferred to a propriety GIS for editing. Vegetated spaces with a minimum of 900 m2 and a width of at least 15 m were selected from the approximately 1025 digitised spaces. Google Earth imagery was used because it is readily available. Euclidean distances of 300 m, 500 m, 800 m and 900 m (taken from literature) were used to buffer the digitized vegetated open spaces and other data on schools, train stations, bus routes and taxi routes in and within 900 m of the catchment. Buffer analysis was carried out. Data from the City of Cape Town and a schools layer were used to determine the number of cemeteries,community parks, nature reserves and school grounds – space regarded as having some protection from development - within the urban edge of the city and what area they covered.Within or partially within the Lourens River quaternary catchment, 593 vegetated open spaces of at least 900 m2 were identified. The analysis showed that only two houses were beyond 300 m from a vegetated open space. There was vegetated open space within 300 m of all the schools, stations, bus and taxi routes within the catchment and in close proximity to the catchment. Within the urban edge, only 124 spaces were found to be protected, of which only one was a nature reserve.Most of the open spaces are not formally designated as open space and are vulnerable to development. Much development has taken place since 2005 in the Lourens River quaternary catchment so action is needed to ensure proximity to vegetated open space remains a positive feature of the area.Expanding the present research to cover a larger area would provide additional baseline data. Further research could consider the loss of open space over time and the impact of management on the quality of designated open space.
116

Geographical study on childhood type 1 diabetes mellitus (T1DM) in Finland

Rytkönen, M. (Mika) 20 March 2004 (has links)
Abstract Type 1 diabetes mellitus (T1DM) among children is of a particular importance in Finland, where its incidence is the highest in the world and still increasing. However, the aetiology of T1DM is not fully known. According to current knowledge, both genetic and environmental factors operate together, leading to an attack by the immune system on the insulin-producing beta cells. The purpose of this study was to investigate the geographical variation in the incidence of T1DM among children aged up to 14 years in Finland. Geographical Information Systems (GIS) and Bayesian spatial statistics were applied in a search for unusual spatial patterns and risk factor associations. The incidence of T1DM among children aged up to 14 years showed clear geographical variations in Finland. Living in a rural environment increased the risk for T1DM, and the risk was particularly high among children living in rural heartland areas. There was no association between the variation in T1DM incidence and the zinc and nitrate concentrations of drinking water. A male excess in the incidence of T1DM was seen in the low-incidence areas. The geographical variation in the risk of T1DM was marked only among children aged up to 9 years. Because genetics is a necessary but not a sufficient cause of T1DM, it could be hypothesized that there are some thus far unknown environmental risk factors affecting particularly younger children in Finland. Some of those factors may be related to a rural environment. The geographical variation in the M/F ratio of T1DM was a challenging observation and warrants more analytical study.
117

Toponym Disambiguation in Information Retrieval

Buscaldi, Davide 12 November 2010 (has links)
In recent years, geography has acquired a great importance in the context of Information Retrieval (IR) and, in general, of the automated processing of information in text. Mobile devices that are able to surf the web and at the same time inform about their position are now a common reality, together with applications that can exploit this data to provide users with locally customised information, such as directions or advertisements. Therefore, it is important to deal properly with the geographic information that is included in electronic texts. The majority of such kind of information is contained as place names, or toponyms. Toponym ambiguity represents an important issue in Geographical Information Retrieval (GIR), due to the fact that queries are geographically constrained. There has been a struggle to nd speci c geographical IR methods that actually outperform traditional IR techniques. Toponym ambiguity may constitute a relevant factor in the inability of current GIR systems to take advantage from geographical knowledge. Recently, some Ph.D. theses have dealt with Toponym Disambiguation (TD) from di erent perspectives, from the development of resources for the evaluation of Toponym Disambiguation (Leidner (2007)) to the use of TD to improve geographical scope resolution (Andogah (2010)). The Ph.D. thesis presented here introduces a TD method based on WordNet and carries out a detailed study of the relationship of Toponym Disambiguation to some IR applications, such as GIR, Question Answering (QA) and Web retrieval. The work presented in this thesis starts with an introduction to the applications in which TD may result useful, together with an analysis of the ambiguity of toponyms in news collections. It could not be possible to study the ambiguity of toponyms without studying the resources that are used as placename repositories; these resources are the equivalent to language dictionaries, which provide the di erent meanings of a given word. / Buscaldi, D. (2010). Toponym Disambiguation in Information Retrieval [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/8912 / Palancia
118

Riverine flooding using GIS and remote sensing

Dambe, Natalia 30 April 2020 (has links)
Floods are caused by extreme meteorological and hydrological changes that are influenced directly or indirectly by human activities within the environment. The flood trends show that floods will reoccur and shall continue to affect the livelihoods, property, agriculture and the surrounding environment. This research has analyzed the riverine flood by integrating remote sensing, Geographical Information Systems (GIS), and hydraulic and/or hydrological modeling, to develop informed flood mapping for flood risk management. The application of Hydrological Engineering Center River Analysis System (HEC RAS) and HEC HMS models, developed by the USA Hydrologic Engineering Center of the Army Corps of Engineers in a data-poor environment of a developing country were successful, as a flood modeling tools in early warning systems and land use planning. The methodology involved data collection, preparation, and model simulation using 30m Shuttle Radar Topographic Mission (SRTM) Digital Elevation Model (DEM) as a critical data input of HEC RAS model. The findings showed that modeling using HEC-RAS and HEC HMS models in a data-poor environment requires intensive data enhancements and adjustments; multiple utilization of open sources data; carrying out multiple model computation iterations and calibration; multiple field observation, which may be constrained with time and resources to get reasonable output.
119

Development of a geographical information system based transport assessment approach in rural South Africa - The Case of Healthcare Accessibility in Cape Winelands District Municipality

Ma-Kiese, Stephane Simon Masamba 27 January 2020 (has links)
For communities in urban and rural areas, access to healthcare facilities is a very significant concern of service delivery to both public policy makers and urban planners. Many healthcare systems set one of their primary objectives to achieve equity and ease of access to healthcare facilities for the populations that they serve. Spatial distribution of population, transport infrastructure, as well as spatial distribution of healthcare facilities are key characteristics that influence the disparities in spatial accessibility to healthcare facilities. Regardless of the permanent interest in transport accessibility, it is often uncertain how different types of accessibility measures relate to one another and which conditions are best for applications. In general, the current study undertakes a statistical comparison among three spatial accessibility measures (representing the main categories of spatial accessibility models) to determine whether they are comparable and/or interchangeable. Specifically, this study aims to use a geographical information system based approach combined with spatial accessibility measures, in a case study, derived from fine spatial resolution datasets, to characterise and divulge spatial variations in individual’s access to healthcare facilities and identify deprived locations/local communities in a selected District Municipality of the Western Cape, South Africa. Results indicate that the main categories of spatial accessibility measures provide different interpretations of accessibility that cannot be reproduced by each other. However, the accessibility measures show a significant similar trend in variations of individual’s accessibility to healthcare services for the communities of Cape Winelands District Municipality. The study establishes that within the Cape Winelands there exist spatial variations in the distribution of accessibility to healthcare and characterises these variations.
120

Analyzing Chlamydia and Gonorrhea Health Disparities from Health Information Systems: A Closer Examination Using Spatial Statistics and Geographical Information Systems

Lai, Patrick T. S. 05 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / The emergence and development of electronic health records have contributed to an abundance of patient data that can greatly be used and analyzed to promote health outcomes and even eliminate health disparities. However, challenges exist in the data received with factors such as data inconsistencies, accuracy issues, and unstructured formatting being evident. Furthermore, the current electronic health records and clinical information systems that are present do not contain the social determinants of health that may enhance our understanding of the characteristics and mechanisms of disease risk and transmission as well as health disparities research. Linkage to external population health databases to incorporate these social determinants of health is often necessary. This study provides an opportunity to identify and analyze health disparities using geographical information systems on two important sexually transmitted diseases in chlamydia and gonorrhea using Marion County, Indiana as the geographical location of interest. Population health data from the Social Assets and Vulnerabilities Indicators community information system and electronic health record data from the Indiana Network for Patient Care will be merged to measure the distribution and variability of greatest chlamydia and gonorrhea risk and to determine where the greatest areas of health disparities exist. A series of both statistical and spatial statistical methods such as a longitudinal measurement of health disparity through the Gini index, a hot-spot and cluster analysis, and a geographically weighted regression will be conducted in this study. The outcome and broader impact of this research will contribute to enhanced surveillance and increased effective strategies in identifying the level of health disparities for sexually transmitted diseases in vulnerable localities and high-risk communities. Additionally, the findings from this study will lead to improved standardization and accuracy in data collection to facilitate subsequent studies involving multiple disparate data sources. Finally, this study will likely introduce ideas for potential social determinants of health to be incorporated into electronic health records and clinical information systems.

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