992 resultados para GIS Techniques


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Vulnerability and sustainability studies of an area help to assess both its level of exposure and capacity to support possible environmental impacts, and it is of primordial importance for proposals of the Legislation on Zoning, Allotment, Land Use/land cover, aiming to stimulate those areas indicated for urban growth, to discourage growth of overcrowded areas, to detect sections with restrictive use, as well as districts for permanent protection. This paper aims to analyze the vulnerability in the Maranhão Ilha, using GIS techniques, geospatial inference intersected with relevant social-environmental indicators.Estudos de vulnerabilidade e de sustentabilidade de uma área ajudam a avaliar o seu grau de exposição e sua capacidade de suporte a possíveis impactos ambientais, sendo fundamental para propostas de Lei de Zoneamento, Parcelamento, Uso e Ocupação do Solo, tendo por finalidade orientar as áreas onde deverá haver estímulo para o crescimento urbano; contenção da malha urbana; detecção de locais com possibilidade de uso restritivo, bem como locais de proteção permanente. Este trabalho propõe analisar o índice de vulnerabilidade a perda de solo da Ilha do Maranhão com base na metodologia proposta por (CREPANI, et al. 2001) e em técnicas de inferência espacial com apoio na AHP (Análise Hierárquica de Processo).

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Many of developing countries are facing crisis in water management due to increasing of population, water scarcity, water contaminations and effects of world economic crisis. Water distribution systems in developing countries are facing many challenges of efficient repair and rehabilitation since the information of water network is very limited, which makes the rehabilitation assessment plans very difficult. Sufficient information with high technology in developed countries makes the assessment for rehabilitation easy. Developing countries have many difficulties to assess the water network causing system failure, deterioration of mains and bad water quality in the network due to pipe corrosion and deterioration. The limited information brought into focus the urgent need to develop economical assessment for rehabilitation of water distribution systems adapted to water utilities. Gaza Strip is subject to a first case study, suffering from severe shortage in the water supply and environmental problems and contamination of underground water resources. This research focuses on improvement of water supply network to reduce the water losses in water network based on limited database using techniques of ArcGIS and commercial water network software (WaterCAD). A new approach for rehabilitation water pipes has been presented in Gaza city case study. Integrated rehabilitation assessment model has been developed for rehabilitation water pipes including three components; hydraulic assessment model, Physical assessment model and Structural assessment model. WaterCAD model has been developed with integrated in ArcGIS to produce the hydraulic assessment model for water network. The model have been designed based on pipe condition assessment with 100 score points as a maximum points for pipe condition. As results from this model, we can indicate that 40% of water pipeline have score points less than 50 points and about 10% of total pipes length have less than 30 score points. By using this model, the rehabilitation plans for each region in Gaza city can be achieved based on available budget and condition of pipes. The second case study is Kuala Lumpur Case from semi-developed countries, which has been used to develop an approach to improve the water network under crucial conditions using, advanced statistical and GIS techniques. Kuala Lumpur (KL) has water losses about 40% and high failure rate, which make severe problem. This case can represent cases in South Asia countries. Kuala Lumpur faced big challenges to reduce the water losses in water network during last 5 years. One of these challenges is high deterioration of asbestos cement (AC) pipes. They need to replace more than 6500 km of AC pipes, which need a huge budget to be achieved. Asbestos cement is subject to deterioration due to various chemical processes that either leach out the cement material or penetrate the concrete to form products that weaken the cement matrix. This case presents an approach for geo-statistical model for modelling pipe failures in a water distribution network. Database of Syabas Company (Kuala Lumpur water company) has been used in developing the model. The statistical models have been calibrated, verified and used to predict failures for both networks and individual pipes. The mathematical formulation developed for failure frequency in Kuala Lumpur was based on different pipeline characteristics, reflecting several factors such as pipe diameter, length, pressure and failure history. Generalized linear model have been applied to predict pipe failures based on District Meter Zone (DMZ) and individual pipe levels. Based on Kuala Lumpur case study, several outputs and implications have been achieved. Correlations between spatial and temporal intervals of pipe failures also have been done using ArcGIS software. Water Pipe Assessment Model (WPAM) has been developed using the analysis of historical pipe failure in Kuala Lumpur which prioritizing the pipe rehabilitation candidates based on ranking system. Frankfurt Water Network in Germany is the third main case study. This case makes an overview for Survival analysis and neural network methods used in water network. Rehabilitation strategies of water pipes have been developed for Frankfurt water network in cooperation with Mainova (Frankfurt Water Company). This thesis also presents a methodology of technical condition assessment of plastic pipes based on simple analysis. This thesis aims to make contribution to improve the prediction of pipe failures in water networks using Geographic Information System (GIS) and Decision Support System (DSS). The output from the technical condition assessment model can be used to estimate future budget needs for rehabilitation and to define pipes with high priority for replacement based on poor condition. rn

Relevância:

70.00% 70.00%

Publicador:

Resumo:

The Keystone XL has a big role for transforming Canadian oil to the USA. The function of the pipeline is decreasing the dependency of the American oil industry on other countries and it will help to limit external debt. The proposed pipeline seeks the most suitable route which cannot damage agricultural and natural water recourses such as the Ogallala Aquifer. Using the Geographic Information System (GIS) techniques, the suggested path in this study got extremely high correct results that will help in the future to use the least cost analysis for similar studies. The route analysis contains different weighted overlay surfaces, each, was influenced by various criteria (slope, geology, population and land use). The resulted least cost path routes for each weighted overlay surface were compared with the original proposed pipeline and each displayed surface was more effective than the proposed Keystone XL pipeline.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

This paper presents the groundwater favorability mapping on a fractured terrain in the eastern portion of Sao Paulo State, Brazil. Remote sensing, airborne geophysical data, photogeologic interpretation, geologic and geomorphologic maps and geographic information system (GIS) techniques have been used. The results of cross-tabulation between these maps and well yield data allowed groundwater prospective parameters in a fractured-bedrock aquifer. These prospective parameters are the base for the favorability analysis whose principle is based on the knowledge-driven method. The mutticriteria analysis (weighted linear combination) was carried out to give a groundwater favorabitity map, because the prospective parameters have different weights of importance and different classes of each parameter. The groundwater favorability map was tested by cross-tabulation with new well yield data and spring occurrence. The wells with the highest values of productivity, as well as all the springs occurrence are situated in the excellent and good favorabitity mapped areas. It shows good coherence between the prospective parameters and the well yield and the importance of GIS techniques for definition of target areas for detail study and wells location. (c) 2008 Elsevier B.V. All rights reserved.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

Every inclined land surface has a potential for soil and water degradation, the seriousness depends on a multitude of parameters such as slope, soil type, geomorphology, rainfall, land use and natural vegetation cover. In Laos this intensified land use leads to reduced vegetation cover, to increased soil erosion, decreasing yield, and finally is likely to influence the hydrological regime. Against this background the Mekong River Commission (MRC) elaborated a spatial explicit Watershed Classification (WSC) for the Lower Mekong Basin. Based on topographic factors derived from a high-resolution Digital Terrain Model, five watershed classes are calculated, giving indication about the sensitivity to resource degradation by soil erosion. The WSC allows spatial priority setting for watershed management and generally supports informed decision making on reconnaissance level. In the conclusions focus is laid on general considerations when GIS techniques are used for spatial decision support in a development context.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

Traditional vegetation mapping methods use high cost, labour-intensive aerial photography interpretation. This approach can be subjective and is limited by factors such as the extent of remnant vegetation, and the differing scale and quality of aerial photography over time. An alternative approach is proposed which integrates a data model, a statistical model and an ecological model using sophisticated Geographic Information Systems (GIS) techniques and rule-based systems to support fine-scale vegetation community modelling. This approach is based on a more realistic representation of vegetation patterns with transitional gradients from one vegetation community to another. Arbitrary, though often unrealistic, sharp boundaries can be imposed on the model by the application of statistical methods. This GIS-integrated multivariate approach is applied to the problem of vegetation mapping in the complex vegetation communities of the Innisfail Lowlands in the Wet Tropics bioregion of Northeastern Australia. The paper presents the full cycle of this vegetation modelling approach including sampling sites, variable selection, model selection, model implementation, internal model assessment, model prediction assessments, models integration of discrete vegetation community models to generate a composite pre-clearing vegetation map, independent data set model validation and model prediction's scale assessments. An accurate pre-clearing vegetation map of the Innisfail Lowlands was generated (0.83r(2)) through GIS integration of 28 separate statistical models. This modelling approach has good potential for wider application, including provision of. vital information for conservation planning and management; a scientific basis for rehabilitation of disturbed and cleared areas; a viable method for the production of adequate vegetation maps for conservation and forestry planning of poorly-studied areas. (c) 2006 Elsevier B.V. All rights reserved.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

O número de municípios infestados pelo Aedes aegypti no Estado do Espírito Santo vem aumentando gradativamente, levando a altas taxas de incidência de dengue ao longo dos anos. Apesar das tentativas de combate à doença, esta se tornou uma das maiores preocupações na saúde pública do Estado. Este estudo se propõe a descrever a dinâmica da expansão da doença no Estado a partir da associação entre variáveis ambientais e populacionais, utilizando dados operacionalizados por meio de técnicas de geoprocessamento. O estudo utilizou como fonte de dados a infestação pelo mosquito vetor e o coeficiente de incidência da doença, as distâncias rodoviárias intermunicipais do Estado, a altitude dos municípios e as variáveis geoclimáticas (temperatura e suficiência de água), incorporadas a uma ferramenta operacional, as Unidades Naturais do Espírito Santo (UNES), representadas em um único mapa operacionalizado em Sistema de Informação Geográfica (SIG), obtido a partir do Sistema Integrado de Bases Georreferenciadas do Estado do Espírito Santo. Para análise dos dados, foi realizada a Regressão de Poisson para os dados de incidência de dengue e Regressão Logística para os de infestação pelo vetor. Em seguida, os dados de infestação pelo mosquito e incidência de dengue foram georreferenciados, utilizando como ferramenta operacional o SIG ArcGIS versão 9.2. Observou-se que a pluviosidade é um fator que contribui para o surgimento de mosquito em áreas não infestadas. Altas temperaturas contribuem para um alto coeficiente de incidência de dengue nos municípios capixabas. A variável distância em relação a municípios populosos é um fator de proteção para a incidência da doença. A grande variabilidade encontrada nos dados, que não é explicada pelas variáveis utilizadas no modelo para incidência da doença, reforça a premissa de que a dengue é condicionada pela interação dinâmica entre muitas variáveis que o estudo não abordou. A espacialização dos dados de infestação pelo mosquito e incidência de dengue e as Zonas Naturais do ES permitiu a visualização da influência das variáveis estatisticamente significantes nos modelos utilizados no padrão da introdução e disseminação da doença no Estado.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Esta dissertação aborda a espacialização dos acidentes de trânsito notificados entre os anos de 2005 e 2013 nos municípios de Fundão, Serra, Vitória, Cariacica, Vila Velha, Viana e Guarapari, que juntos compõem a Região Metropolitana da Grande Vitória (RMGV). Para o cumprimento deste propósito, realizou-se um diagnóstico temporal e espacial dos acidentes de trânsito ocorridos nessa região, analisando-se o acelerado crescimento da frota veicular, a situação da atual infraestrutura viária e o crescimento demográfico. Além disso, foram listadas as principais variáveis de risco responsáveis por ocasionar acidentes de trânsito. Quanto à fundamentação teórica, foi construída a partir da Geografia dos Transportes, que forneceu subsídios para contextualizar a importância da análise espacial geográfica sobre o fenômeno aqui tratado. Na sequência, estimaram-se os custos gerados por esse fenômeno, chegando à cifra de mais de R$ 900 milhões de custos associados aos acidentes de trânsito da RMGV em 2013. Utilizando-se de técnicas de geoestatística e de geoprocessamento, identificaram-se as áreas de concentração de acidentes de trânsito na RMGV, conforme as tipologias de colisões e choques, capotamentos e tombamentos e atropelamentos. Logrou-se, como conclusão, que 1) além do crescimento em quantidade e concentração das ocorrências, houve também, no decorrer da série histórica, o espraiamento dos registros de acidentes de trânsito na RMGV, e 2) os acidentes, conforme sua tipologia, concentram-se em diferentes áreas da região estudada.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

This study presents a first attempt to extend the “Multi-scale integrated analysis of societal and ecosystem metabolism (MuSIASEM)” approach to a spatial dimension using GIS techniques in the Metropolitan area of Barcelona. We use a combination of census and commercial databases along with a detailed land cover map to create a layer of Common Geographic Units that we populate with the local values of human time spent in different activities according to MuSIASEM hierarchical typology. In this way, we mapped the hours of available human time, in regards to the working hours spent in different locations, putting in evidence the gradients in spatial density between the residential location of workers (generating the work supply) and the places where the working hours are actually taking place. We found a strong three-modal pattern of clumps of areas with different combinations of values of time spent on household activities and on paid work. We also measured and mapped spatial segregation between these two activities and put forward the conjecture that this segregation increases with higher energy throughput, as the size of the functional units must be able to cope with the flow of exosomatic energy. Finally, we discuss the effectiveness of the approach by comparing our geographic representation of exosomatic throughput to the one issued from conventional methods.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Hebes Chasma is an 8 km deep, 126 by 314 km, isolated basin that is partially filled with interior layered deposits (ILD), massive deposits of water altered strata. By analyzing the ILD’s structure, stratigraphy and mineralogy, as well as the perimeter faults exposed in the plateau adjacent to the chasma, the evolution and depositional history of Hebes Chasma is interpreted. Three distinct ILD units were found and are informally referred to as the Lower, Upper and Late ILDs. These units have differing layer thicknesses, layer attitudes, mineralogies and erosional landforms. Based on observations of the plateau, wall morphology and slump blocks within the chasma’s interior, chasma evolution appears to be controlled by cross-faults that progressively detached sections of the wall. A scenario involving the loss of subsurface volume and ash fall events is proposed as the dominant setting throughout Hebes’ geologic history.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

The research record on the quantification of sediment transport processes in periglacial mountain environments in Scandimvia dates back to the 1950s. A wide range of measurements is. available, especially from the Karkevagge region of northern Sweden. Within this paper satellite image analysis and tools provided by geographic information systems (GIS) are exploited in order to extend and improve this research and to complement geophysical methods. The processes of interest include mass movements such as solifluction, slope wash, dirty avalanches and rock-and boulder falls. Geomorphic process units have been derived in order to allow quantification via GIS techniques at a catchment scale. Mass movement rates based on existing Field measurements are employed in the budget calculation. In the Karkevagge catch ment. 80% of the area can be identified either as a source area for sediments or as a zone where sediments are deposited. The overall budget for the slopes beneath the rockwalls in the Karkevagge is approximately 680 t a(-1) whilst about 150 : a-1 are transported into the fluvial System.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

As técnicas de sensoriarnento remoto e geoprocessamento são fundamentais para processamento e integração de dados de mapeamento geológico/geotécnico, principalmente estudos de gerenciamento e planejamento. A área estudada compreende o município de Três Cachoeiras. Litoral Norte do Rio Grande do Sul o qual inclui-se na "Reserva da Biosfera da Mata Atlântica". O município tem st: deparado com problemas de localização de sitios adequados à disposição final dos resíduos sólidos. bem como o assentamento de loteamentos residenciais e industriais, localização de jazidas de extração de material para construção, fontes de abastecimento de água e necessidade de criação de áreas de preservação ambiental. O objetivo deste trabalho foi produzir mapeamentos da área em questão, através da pesquisa geológico-geotécnica desenvolvida com emprego de imagens de satélite e fotografias aéreas, em que as informações foram cruzadas no SIG. Baseado nisto, investigaram-se os aspectos acima mencionados. a partir de uma contribuição geológico/geotécnica ao município, incluindo-se levantamento de campo, fotointerpretação, processamento e classificação de imagens do município de Três Cachoeiras, sendo os dados integrados num sistema de geoprocessamento. Utilizando-se cartas planialtimétricas, fotografias aéreas e imagem de satélite LANDSAT TM5. foram criados planos de informação como o limite da área estudada, a estrutura viária municipal, a delimitação de reservas ecológicas baseadas na legislação ambiental vigente e, por meio do modelo numérico do terreno, a carta de declividade. A fotointerpretação gerou planos de rede de drenagem, litológica. morfoestruturas e formações superficiais. Os dados de campo. sobrepostos às litológicas obtidas por fotointerpretação, produziram a carta litológica. No tratamento das imagem, foram gerados produtos com contraste, operações entre bandas, filtragens e análise de componentes principais, os quais contribuíram parira classificação da imagem e resultando nos planos de rochas/solos e cobertura/uso do solo (carta de uso atual do solo). O cruzamento destas informações permitiu a obtenção da carta de formações superficiais, lidrogeológica que, juntamente com as cartas litológica, declividades e uso atual do solo distribuíram os atributos do meio físico em planos elaborados por novos cruzamentos, que satisfazem o objetivo do estudo, sendo estes planos o produto final, ou seja, cartas de recomendação: a extração de materiais para construção civil; a implantação de obras de infraestrutura; a disposição de resíduos sólidos e loteamentos; geotécnica à agricultura; à implantação de áreas destinadas à preservação ambienta1 e recuperação.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

The present paper reports the assessment of the vegetation occupancy rate of the roadside, through analysis of aerial photographs. Using such value the potential of these areas to be employed as carbon (C) sinks was also assessed. Moreover, for the areas suitable for afforestation, the potential for carbon sequestration was estimated considering different species of vegetation, both native (scenario 1) and exotic (formed by Pinus sp. and Eucalyptus sp. - scenario 2). The study was carried out through GIS techniques and two regions were considered. A set of equations was used to estimate the rate of occupancy over the study areas, as well as amounts of fixed C under the above scenarios. The average occupancy rate was 0.06%. The simulation showed a higher potential for C sequestration in scenario 2, being the estimated amounts of CO(2) sequestered from the atmosphere per km of roadside: 131 tons of CO(2) km(-1) of highway to native species and 655 tons of CO(2) km(-1) of highway for exotic species (over period of 10 years for both estimates). If we consider the whole road network of the São Paulo State (approximately 190 000 km) and that a considerable part of this road work is suitable to receive this kind of service, it is possible to predict the very high potential for C sequestration if managers and planners consider roadside as area for afforestation.