Geographic information systems (GIS) are developing in a rapidly expanding distributed environment. With the ever-increasing growth of computer networks and the Internet in particular, it is imperative that GIS take advantage of distributed data technologies to provide users and applications with shared and improved access to geographic data.Geographic data distribution design is concerned with determining what data gets placed at which computer network sites and involves the issues of data partitioning, allocation and dynamic migration. Partitioning is concerned with how data, or fragments of the data, are apportioned to partitions. These partitions must then be assigned to network sites in an allocation process. Because data usage and access changes by applications in a dynamic environment, migration strategies are necessary to redistribute the data. In order for data distribution to reflect current usage patterns of applications, the design process must obtain and accumulate data usage information from applications.This dissertation first details the predicate fragmentation (PF) model. The core of the model is the PF tree that has been developed and implemented to store and maintain usage information. User predicates, obtained from application queries, are inserted into the tree and primitive predicates can be identified from the tree. These primitive predicates define the fragmentation from which a data distribution can be determined. Predicate insertion and pruning operations are essential to the maintenance of the tree structure.A methodology that uses the PF model to obtain a partitioning, allocation and migration strategy is then outlined. The fragments identified from the PF trees are aggregated into partitions that are then assigned to individual network sites using a site access allocation strategy. A dynamic migration strategy then uses changes in the PF ++ / trees to identify the data that must be migrated to a new site in order to accommodate the changing application environment.The implementation of the geographic data distribution methodology is referred to as GEODDIS. The methodology was tested and evaluated using a mineral occurrence application called GEOMINE which was developed with the ArcInfo GIS. The results indicate that geographic data distribution performs well when successive applications have similar data usage requirements. The implementation of the geographic data distribution methodology is referred to as GEODDIS. The methodology was tested and evaluated using a mineral occurrence application called GEOMINE which was developed with the ArcInfo GIS. The results indicate that geographic data distribution performs well when successive applications have similar data usage requirements. For applications with very different data usage patterns, the performance decreases to the worst case scenario where all the data must be transferred to the site where it is used. The tree pruning and data migration operations are essential to maintaining a PF tree structure and distribution that reflects the current data usage of applications.

Errors are inherent to all spatial datasets and give rise to a level of uncertainty in the final product of a geographic information system (GIS). There is growing recognition that the uncertainty associated with spatial information should be represented to users in a comprehensive and unambiguous way. However, the effects on decision-making of such representations have not been thoroughly investigated. Studies from the psychological literature indicate decision-making biases when information is uncertain. This study explores the effects of representing spatial uncertainty, through an examination of how decision-making may be affected by the introduction of thematic uncertainty and an investigation of the effects of different representations of positional uncertainty on decision-making. / Two case studies are presented. The first of these considers the effects on decision-making of including thematic uncertainty information within the context of an airport siting decision task. An extremely significant tendency to select a zone for which the thematic classification is known to be of high certainty was observed. The reluctance to select a zone for which the thematic classification is of low certainty was strong enough to sometimes lead to decision-making that can only be described as irrational. / The second case study investigates how decision-making may be affected by different representations of positional uncertainty within the context of maritime navigation. The same uncertainty information was presented to participants using four different display methods. Significant differences in their decisions were observed. Strong preferences for certain display methods were also exhibited, with some representations being ranked significantly higher than others. / The findings from these preliminary studies demonstrate that the inclusion of uncertainty information does influence decision-making but does not necessarily lead to better decisions. A bias against information of low certainty was observed, sometimes leading to the making of irrational decisions. In addition, the form of uncertainty representation itself may affect decision-making. Further research into the effects on decision-making of representing spatial uncertainty is needed before it can be assumed that the inclusion of such information will lead to more informed decisions being made.

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Made available in DSpace on 2014-06-11T19:24:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-05-25Bitstream added on 2014-06-13T18:21:03Z : No. of bitstreams: 1 souza_sa_me_botfca.pdf: 1747970 bytes, checksum: a0d929f25135060080a59ba7740982b7 (MD5) / Este trabalho teve como objetivo principal utilizar uma metodologia apoiada em técnicas de geoprocessamento para identificar e quantificar o tipo de cobertura vegetal encontrada em parte do município de Botucatu - SP, desta forma o mesmo foi dividido em três fases. Na primeira fase, efetuou-se o levantamento dos dados e a preparação dos mesmos para o georreferenciamento. Na segunda fase, as fotos foram georreferenciadas tendo por base a carta topográfica rasterizada do IBGE na escala 1:50.000. Nesse processo foram utilizados três softwares (MicroStation, Image Analyst e ERDAS). Após esse processo montou-se um mosaico da área de estudo para o ano de 1972 e 2000, efetuou-se o tratamento digital dos produtos e procedeu-se a etapa de classificação não supervisionada para ambas as épocas. Na terceira fase, foram geradas cartas temáticas que propiciaram a investigação das mudanças ocorridas no período de 28 anos para a área. Os resultados obtidos propiciaram a verificação e constatação da qualidade da classificação não supervisionada obtida. De acordo com os resultados obtidos, chegou-se à conclusão de que na fase de georreferenciamento das fotografias aéreas, a metodologia proposta mostrou-se eficiente uma vez que a mesma foi baseada em fundamentos científicos de análises de resíduos do processo, propiciando a utilização de cartas matriciais como fonte de referência. Assim, a etapa de coleta de dados em campo não mais necessita ser executada acarretando em economia, agilidade no processo e conseqüente redução de custos. A classificação não supervisionada não se mostrou satisfatória devido a erros de inclusão e omissão de pixels decorrentes do classificador utilizado. Através da interpretação visual dos mosaicos obtiveram-se dados acerca das alterações do uso do solo para os anos de 1972 e 2000. Os dados mostraram... / This work aimed to apply geoprocessing techniques to identify and to quantify the types of vegetal coverings in part of the county Botucatu - SP. The first phase comprised the surveying and preparation of data for georeferencing. In the second phase, the photos have been georreferencied based on the digital topographic map of the IBGE in 1:50.000 scale. In this process, two had been used softwares have been used (MicroStation, Image Analyst and ERDAS). After this, it has been set mosaic of the study area for the year of 1972 and 2000, the products have received the digital treatment and have been classified through unsupervised classification. In the third phase, thematic maps have been generated, which allowed investigating the charges for the period of 28 years. The results have propitiated the verification of the accuracy of the classification. According to the resilts, it has been stated that suggested methodology for georeferencing has been efficient, statistically based on the analyses of residues, allowing the use of digital maps as reference collecting field data should any more been executed, resilting in economy, agility and cost effectives. The results of the unsupervised classification have not been satisfactory due to the errors of inclusion and the omission of pixels as consequence of the classifier. The visual interpretation of the mosaics allowed obtaining the land use changes for the years of 1972 and 2000.

Orientador: Zacarias Xavier de Barros / Banca: Lincoln Gehring Cardoso / Banca: Ligia Barrozo Simões / Resumo: Este trabalho teve como objetivo principal utilizar uma metodologia apoiada em técnicas de geoprocessamento para identificar e quantificar o tipo de cobertura vegetal encontrada em parte do município de Botucatu - SP, desta forma o mesmo foi dividido em três fases. Na primeira fase, efetuou-se o levantamento dos dados e a preparação dos mesmos para o georreferenciamento. Na segunda fase, as fotos foram georreferenciadas tendo por base a carta topográfica rasterizada do IBGE na escala 1:50.000. Nesse processo foram utilizados três softwares (MicroStation, Image Analyst e ERDAS). Após esse processo montou-se um mosaico da área de estudo para o ano de 1972 e 2000, efetuou-se o tratamento digital dos produtos e procedeu-se a etapa de classificação não supervisionada para ambas as épocas. Na terceira fase, foram geradas cartas temáticas que propiciaram a investigação das mudanças ocorridas no período de 28 anos para a área. Os resultados obtidos propiciaram a verificação e constatação da qualidade da classificação não supervisionada obtida. De acordo com os resultados obtidos, chegou-se à conclusão de que na fase de georreferenciamento das fotografias aéreas, a metodologia proposta mostrou-se eficiente uma vez que a mesma foi baseada em fundamentos científicos de análises de resíduos do processo, propiciando a utilização de cartas matriciais como fonte de referência. Assim, a etapa de coleta de dados em campo não mais necessita ser executada acarretando em economia, agilidade no processo e conseqüente redução de custos. A classificação não supervisionada não se mostrou satisfatória devido a erros de inclusão e omissão de pixels decorrentes do classificador utilizado. Através da interpretação visual dos mosaicos obtiveram-se dados acerca das alterações do uso do solo para os anos de 1972 e 2000. Os dados mostraram... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This work aimed to apply geoprocessing techniques to identify and to quantify the types of vegetal coverings in part of the county Botucatu - SP. The first phase comprised the surveying and preparation of data for georeferencing. In the second phase, the photos have been georreferencied based on the digital topographic map of the IBGE in 1:50.000 scale. In this process, two had been used softwares have been used (MicroStation, Image Analyst and ERDAS). After this, it has been set mosaic of the study area for the year of 1972 and 2000, the products have received the digital treatment and have been classified through unsupervised classification. In the third phase, thematic maps have been generated, which allowed investigating the charges for the period of 28 years. The results have propitiated the verification of the accuracy of the classification. According to the resilts, it has been stated that suggested methodology for georeferencing has been efficient, statistically based on the analyses of residues, allowing the use of digital maps as reference collecting field data should any more been executed, resilting in economy, agility and cost effectives. The results of the unsupervised classification have not been satisfactory due to the errors of inclusion and the omission of pixels as consequence of the classifier. The visual interpretation of the mosaics allowed obtaining the land use changes for the years of 1972 and 2000. / Mestre

Orientadores: Jose Geraldo Pena de Andrade, Maria Teresa Françoso / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-04T13:02:37Z (GMT). No. of bitstreams: 1 Ferreira_CristianoDorca_M.pdf: 2012459 bytes, checksum: e6ea5fd321ecf7ce4c4aab81bff973b9 (MD5) Previous issue date: 2005 / Resumo: Os Sistemas de Informações Geográficas (SIG) são uma forma moderna e eficaz de interligar informações alfanuméricas a uma base geográfica espacial (informação cartográfica), permitindo as mais distintas análises conjuntas. Embora o SIG seja uma ferramenta de gestão desejável, sua implantação efetiva é onerosa e um planejamento mal feito pode levar ao malogro todas as expectativas de benefícios que se objetivavam com a sua implantação. Os pequenos sistemas de abastecimentos de água que atendem as pequenas e médias cidades, via de regra, não dispõem de corpo técnico qualificado e de recursos para a implantação adequada de um SIG. Neste sentido, o presente trabalho apresenta um guia para implantação do SIG para estes sistemas, com base em informações relatadas na literatura / Abstract: The Geographical Information System (GIS) modem and effective form of join alphanumeric information to a space geographical base (cartographic information), allowing the most different united analyses. Although GIS a tool of desirable administration, your implantation it executes it is onerous and a planning badly fact can take to the failure all the expectations of benefits that were aimed at with your implantation. The small systems of water supplies that assist the small ones and averages cities, rule road if they don't have qualified technical body and resources for the appropriate implantation of a GIS this sense the present work presents a systematic of low cost implantation of GIS these systems, based in informations of literature / Mestrado / Recursos Hidricos / Mestre em Engenharia Civil

Landscape is about the relationship between people and place and in 2000 was defined by the European Landscape Commission (ELC) as "an area as perceived by people whose character is the result of natural and human actions and interactions”. In the 70s the reason for studying the landscape was because of the necessity of attributing a value to it. Nowadays the motivations behind managing, conserving and enhancing the landscape is because the landscape is the place where people belong to and, consciously or not, recognise themselves. In addition, people identify different landscapes on the basis of the particular combinations of the elements in the landscape. As a consequence a landscape can be distinguished from another on the basis of its character which, according to the Landscape Character Assessment (LCA) guidance for England and Scotland (C. Swanwick and Land Use Consultant, 2002), is defined as “a distinct, recognisable and consistent pattern of elements in the landscape that makes one landscape different from the other rather than better or worse”. This definition was the starting point of a PhD research project aimed at developing and implementing a methodology able to identify and quantify the character of the Scottish landscape through the application of GIS and statistics. The reason for doing this research was to provide the landscape architects and practitioners with a tool that could help them to define the landscape character types in a more consistent, objective, and scientifically robust way. One of the objectives of the research was to identify the spatial patterns formed by the landscape elements by taking into account the influence of the spatial location. The first law of geography, which states that "everything is related to everything else but near things are more related than distant ones" (W Tobler, 1970), was transposed in the assumption of the presence of spatial autocorrelation amongst the data which contributes to form spatial patterns within the data. Since landscape comprises of many elements, data were also multivariate, thus the analysis required a method of calculation able to deal simultaneously with multivariate and spatial autocorrelation issues. MULTISPATI-PCA, a spatially constrained Principal Component Analysis, was the statistical technique applied for the analysis of the data whose results showed that it was possible to detect the spatial structure of the data and that each spatial pattern corresponded to a distinct landscape. Despite their importance in forming the character of the landscape, aesthetic and perceptual aspects were not inlcuded in MULTISPATI-PCA analysis. It was preferred to test the technique only on data that were quantifiable in a more objective way. Perhaps taking into account the human perception of the landscape can be the starting point for future investigation.

Land, water and natural resources are under increasing pressure due to rising demands for food and energy from the rapidly growing global population. Across a catchment there can be multiple stakeholders with conflicting opinions over how space and resources should be used and managed. Consequently, it is important to consider the suitability of a catchment for a particular purpose to optimise use of the area and minimise potential conflicts and impacts on the wider environment. Aquaculture is a significant contributor to world food supply and as fisheries are unlikely to increase it is expected that the industry will continue to grow and expand in the future to help meet food security requirements. As a result, it is essential that the sector aims for sustainable development within the most suitable locations. However, it can be difficult to assess the suitability of multiple large catchments and some issues may not be immediately apparent. This project aimed to show how spatial models could be used as decision support tools to evaluate the suitability of large catchments for sustainable aquaculture. Four large areas of importance to aquaculture were selected; covering 10,148km2, 26,225km2, 48,319km2 and 66,283km2 in Bangladesh, China, Thailand and Vietnam respectively. Asia is by far the most dominant aquaculture region in the world and each of the four study areas contribute to local, regional and global food supplies. The study area in Bangladesh was located in Khulna region in the south west of the country and the main species of focus were prawn and shrimp. The Chinese study area was located in the south eastern province of Guangdong and the main species covered were tilapia and shrimp. Similarly, in Thailand, the main species evaluated were tilapia and shrimp whilst the study area extended across the Central region. Finally, the largest study area was the Mekong Delta in Vietnam and the main species of focus in this area were pangasius catfish and shrimp. One of the challenges in modelling large catchments is model applicability and data availability. Often, the required data are not available (or accessible) and it would be difficult, time consuming and expensive to collect new information. Furthermore, when assessing multiple areas is it vital that a representative and unbiased approach is used where no one catchment is favoured over the other due to higher quality data. Therefore, this study used data that are available for almost any area in the world; allowing future application of the models and enabling effective and unbiased decision support. Four modelling stages were employed in this study to evaluate the suitability of large catchments for sustainable aquaculture development. The first stage was the classification of seasonal land use models from satellite imagery. This provides information on what the land is used for and how aquaculture could impact or be impacted by the wider environment. The second step was the development of seasonal models of site suitability using optimal values within a GIS-based multi-stage framework. These models identify which locations are best for culture and can also be used to estimate the availability of areas for food production. The next stage investigated the use of Maxent as a novel approach in site suitability modelling to evaluate the conditions experienced by existing farms. The information from Maxent can be used to identify trends, opportunities and concerns related to sustainable management and farm locations. Finally, qualitative models of non-point source pollution (NPSP) were developed which assess the risk of NPSP within a catchment. NPSP is an issue which can impact both aquaculture and the wider environment. Thus, it is important to understand the areas within a catchment where NPSP risk is higher enabling the establishment of monitoring and/or mitigation procedures. The models support the ecosystem approach to aquaculture (EAA) and enable objective planning and management strategies to enhance productivity across large catchments without negatively impacting the environment. In order to meet growing food requirements, large areas will need to be used for agriculture and aquaculture; therefore, analysis at a wider catchment level, which complements assessment at a local scale, is required as it allows a holistic view of the situation. The work presented here illustrates the potential use of spatial models across large catchments and considers the suitability of the areas for aquaculture development.

Globally fish production has continued to increase during recent years at a rate exceeding that of human population growth. However the contribution from capture fisheries has remained largely static since the late 1980s with the increase in production being accounted for by dramatic growth in the aquaculture sector. As of 2012 aquaculture accounted for approximately 42% of total fisheries production and 78% of inland fish production. In view of these figures it is unsurprising that for a number of regions aquaculture represents an important source of both food security and income. The use of Geographical Information Systems (GIS) and spatial data have seen substantial developments in recent years with the help of increasingly affordable computing capacity. From an aquaculture perspective the use of GIS has shown significant potential as a means of combining varied data sources, including those acquired via remote sensing, into models to provide decision support in relation to site selection. A common theme amongst site suitability assessments is the incorporation of climate variables relating to temperature and water availability. These factors in turn can have a significant influence on aquaculture in terms of water availability and quality, and temperature modulated growth performance. There is now a strong consensus that during the 20th century, and especially during recent decades, the earth has experienced a significant warming trend. There is also strong agreement that this warming trend is at least partially a consequence of anthropogenic greenhouse gas emissions and that some degree of further warming is inevitable. While global warming is typically discussed in terms of degrees centigrade of average global temperature increase the full effects in terms of climate changes will be varied both in terms of location and season. The current project focuses on site suitability for aquaculture in relation to changing climate conditions. Significant use is made of GIS and a range of spatial data including remotely sensed data and output from a series of climate models. The project consists of a number of key components: 1. Vulnerability of aquaculture related livelihoods to climate change was assessed at the global scale based on the concept of vulnerability to climate related impacts as a function of sensitivity to climate change, exposure to climate change, and adaptive capacity. Use was made of national level statistics along with gridded climate and population data. Climate change scenarios were supplied using the MAGICC/SCENGEN climate modelling tools. Analysis was conducted for aquaculture in freshwater, brackish, and marine environments with outputs represented as a series of raster images. A number of Asian countries (Vietnam, Bangladesh, Laos, and China) were indicated as most vulnerable to impacts on freshwater production. Vietnam, Thailand, Egypt and Ecuador stood out in terms of brackish water production. Norway and Chile were considered most vulnerable to impacts on Marine production while a number of Asian countries (China, Vietnam, and the Philippines) also ranked highly. 2. Site suitability for pond-based aquaculture was modelled at the global scale using a 10 arcsecond grid. Data from an ensemble of 13 climate models was used to model pond temperature and water availability for rain fed ponds under late 20th century conditions and for a 2°C global warming scenario. Two methods are demonstrated for combining data with a focus on the culture of warm water species. Results suggest both positive and negative impacts in relation to the 2°C warming scenario depending on location and season. Some areas are projected to see negative effects from maximum temperatures during the warmest parts of the year while for many regions there are likely to be potential increases in growth performance during colder months with possible expansion into previously unsuitable areas. 3. Methods for detecting surface water using remotely sensed data were investigated for Bangladesh. Use was made of data from the Moderate-resolution Imaging Spectroradiometer (MODIS) and Landsat ETM+ instruments with accuracy assessed against ground truth data collected in the field. A time series was constructed using all available MODIS data (approximately 13 years with an 8 day temporal resolution) to show areas of: surface water, land, and mixed land and water. The time series was then analysed to produce a layer showing the percentage of the total time series where surface water is indicated thus providing a spatial representation of flood prevalence. 4. A land cover data set was produced using 9 Landsat ETM+ scenes to cover the majority of Bangladesh. 10 different classification routines were evaluated including a decision tree approach unique to the current study. Classification results were assessed against two sets of ground control points produced: one based on field collected ground truth data and the other using a stratified random sampling procedure in association with visual analysis of high resolution true colour satellite images and ETM+ composites. The most accurate classifications were provided by the decision tree method developed for the current study and a Multi-Layer Perceptron (MLP) neural network based classifier. 5. Site suitability for pond-based aquaculture within Bangladesh was assessed using a GIS in combination with the ETM+ based land cover data, the MODIS based surface water time series, and components of the global site suitability assessment including modelled pond temperature data. Assessments were made based on late 20th century conditions and a 2°C global warming scenario. The MODIS surface water time series was also used to show the effects of storm surge flooding in relation to cyclone Aila that struck Bangladesh on 25th May 2009. The south and east of the country were considered most suitable for aquaculture due to more favourable cold season temperatures and higher water balance values. The north west of the country was considered least favourable due to higher maximum modelled pond temperatures and lower water balance values. The effect of the 2°C warming scenario was to enhance these trends. To date the potential spatial implications of changing climate for aquaculture has been significantly under researched. In this respect the current study provides a highly useful indication of where aquaculture related livelihoods may be vulnerable. In addition valuable and unique insights are provided into the distribution of areas of both potential increased, as well as decreased, suitability for existing aquaculture and further aquaculture development.