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A prototype expert system for the geometric rectification of remotely-sensed imagesHeard, Michael Ian January 1993 (has links)
No description available.
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Innovative Techniques for Digitizing and Restoring Deteriorated Historical DocumentsLandon, Jr., George V. 01 January 2008 (has links)
Recent large-scale document digitization initiatives have created new modes of access to modern library collections with the development of new hardware and software technologies. Most commonly, these digitization projects focus on accurately scanning bound texts, some reaching an efficiency of more than one million volumes per year. While vast digital collections are changing the way users access texts, current scanning paradigms can not handle many non-standard materials. Documentation forms such as manuscripts, scrolls, codices, deteriorated film, epigraphy, and rock art all hold a wealth of human knowledge in physical forms not accessible by standard book scanning technologies. This great omission motivates the development of new technology, presented by this thesis, that is not-only effective with deteriorated bound works, damaged manuscripts, and disintegrating photonegatives but also easily utilized by non-technical staff. First, a novel point light source calibration technique is presented that can be performed by library staff. Then, a photometric correction technique which uses known illumination and surface properties to remove shading distortions in deteriorated document images can be automatically applied. To complete the restoration process, a geometric correction is applied. Also unique to this work is the development of an image-based uncalibrated document scanner that utilizes the transmissivity of document substrates. This scanner extracts intrinsic document color information from one or both sides of a document. Simultaneously, the document shape is estimated to obtain distortion information. Lastly, this thesis provides a restoration framework for damaged photographic negatives that corrects photometric and geometric distortions. Current restoration techniques for the discussed form of negatives require physical manipulation to the photograph. The novel acquisition and restoration system presented here provides the first known solution to digitize and restore deteriorated photographic negatives without damaging the original negative in any way. This thesis work develops new methods of document scanning and restoration suitable for wide-scale deployment. By creating easy to access technologies, library staff can implement their own scanning initiatives and large-scale scanning projects can expand their current document-sets.
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Extraction de fragments forestiers et caractérisation de leurs évolutions spatio-temporelles pour évaluer l'effet de l'histoire sur la biodiversité : une approche multi-sources / Forest fragments extraction and characterization of their spatiotemporal evolution to evaluate the effects of history on biodiversity : a multi-source approachHerrault, Pierre-Alexis 19 June 2015 (has links)
La biodiversité dans les paysages dépend des caractéristiques de ce paysage mais peut aussi être influencée par son histoire. En effet, certaines espèces ne réagissent pas immédiatement à une perturbation mais peuvent montrer un temps de réponse plus ou moins long. De ce fait, la prise en compte de l'évolution de l'habitat des espèces est devenue un enjeu important en écologie depuis quelques années, pour mieux comprendre la présence ou la diversité biologique actuelle. L'objectif de cette thèse en géomatique s'inscrit dans ce contexte applicatif d'écologie historique. Le sujet que nous traitons porte sur l'extraction automatique d'îlots boisés et la caractérisation de leur évolution spatio-temporelle depuis le milieu du XIXe siècle pour modéliser l'effet de leur trajectoire historique sur la diversité actuelle en syrphes forestiers (Diptera : Syrphidae). Le site d'étude est un paysage agri-forestier des Coteaux de Gascogne. La démarche générale proposée se compose de trois étapes principales : (1) la constitution de la base de données spatiales des îlots boisés intégrant plusieurs sources de données hétérogènes, (2) l'appariement des îlots boisés aux différentes dates avec la caractérisation de leur évolution spatio-temporelle, (3) la modélisation statistique des relations espèces-habitats intégrant l'histoire comme un des facteurs explicatifs de la diversité en syrphes observée. Plusieurs contributions méthodologiques ont été apportées à cette démarche. Nous avons proposé une nouvelle méthode de correction géométrique fondée sur la régression ridge à noyau pour rendre compatible les données spatiales anciennes et actuelles mobilisées. Nous avons également développé une approche et un outil de vectorisation automatique des forêts dans les dessins-minutes de la carte d'Etat-Major du XIXe siècle. Enfin, une première évaluation de l'impact de l'incertitude spatiale sur la réponse des modèles espèces-habitats a également été initiée. D'un point de vue écologique, les résultats ont révélé un effet significatif de la continuité temporelle des habitats sur la diversité en syrphes forestiers. Nous avons montré que les forêts les plus isolées présentaient une dette d'extinction ou un crédit de colonisation selon le type d'évolutions apparues au cours de la dernière période étudiée (1979-2010). Il s'est avéré qu'une durée de 30 ans n'était pas suffisante aux syrphes forestiers pour qu'ils retrouvent un été d'équilibre à la suite d'une évolution spatiale de leur habitat isolé. / Biodiversity in landscapes depends on landscape spatial patterns but can also be influenced by landscape history. Indeed, some species are likely to respond in the longer term to habitat disturbances. Therefore, in recent years, landscape dynamics have become a possible factor to explain current biodiversity. The aim of this thesis in GIS is part of this historical ecology context. We are dealing with automatic extraction of forest patches and characterization of their spatiotemporal evolution. The objective is to evaluate forest dynamics effects on current diversity of forest hoverflies. (Diptera: Syrphidae) in the agri-forestry landscape of Coteaux de Gascogne. The proposed general approach consists of three main steps: (1) the forest spatial database production from heterogeneous sources, (2) forest patches matching and characterization of their spatiotemporal evolution, (3) species-habitat modeling while integrating history as one of the factors likely to explain hoverflies diversity. Several methodological contributions were made. We proposed a new geometric correction approach based on kernel ridge regression to make consistent past and present selected data sources. We also developed an automatic extraction approach of forest from Historical Map of France of the 19th century. Finally, spatial uncertainty effects on ecological models responses have been assessed. From an ecological viewpoint, a significant effect from historical continuity of patches on forest hoverflies diversity was revealed. The most isolated fragments presented an extinction debt or a colonization credit according to area dynamics occurred in the last time-period (1970-2010). As it turns out, 30 years was not sufficient for forest hoverflies to reach new equilibrium after isolated habitat changes.
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Análise de modelos digitais de superfície gerados a partir de imagens do sensor PRISM/ALOS / Analysis of digital surface models generated from images of PRISM/ ALOS sensorOliveira, Leila Freitas de 31 October 2011 (has links)
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Previous issue date: 2011-10-31 / The purpose of this study is the quality assessment of Digital Surface Models (DSMs) generated from stereo pairs of PRISM/ALOS images, considering aspects regarding different approaches of geometric correction, image matching strategies, grid distance and positional accuracy. The standard of accuracy expected for the products evaluated considers the Technical Standards of the National Cartography, defined by the Cartographic Accuracy Standard of the brazilian systematic mapping for 1:25,000 scale, class A. In the geometric correction step are considered the approaches of rigorous sensor model and generalized model using Rational Polynomial Coefficients (RPCs).
The ground control points used in geometric correction and in global assessment of the positional accuracy of orthoimages and DSMs, were determined by GPS relative static positioning. The local assessments, aiming the analysis of DSMs as to different morphologies, are performed from control points determined by relative kinematic GPS positioning in low-slope surfaces and on inclined surfaces. The global results achieved indicate that the geometric modeling, the number of control points considered, as well as the strategies for image matching and grid distance influence the vertical accuracy of the DSM, in relation to the expected accuracy standard. The experiments performed to orthorectify the nadir images using the DSMs previously selected, show that variations as to these factors, beyond different vertical accuracies, not affect the expected horizontal accuracy of the orthoimage, portraying, therefore, the same horizontal quality standard for the MDSs used in the orthorectification. The statistical tests for trend and precision detection, confirm the relative consistency on all orthoimages and MDSs generated. However, most of these products presents trend, except for some isolated cases. As to the local assessment, the results indicate that different morphologies influence the accuracy of the DSM, in relation to global assessment. In general, the results in low-slope areas present greater accuracy. The local analyses also indicate that the slope, associated with factors such as failure image matching and interpolation procedures, provides degradation of DSM vertical accuracy. / O objetivo deste trabalho é a análise da qualidade de Modelos Digitais de
Superfície (MDSs) gerados a partir de pares estereoscópicos de imagens do sensor PRISM/ALOS, considerando-se aspectos quanto a diferentes abordagens de correção geométrica, estratégias de correlação de imagens, espaçamento da grade e acurácia posicional. O padrão de acurácia esperado para os produtos avaliados considera as Normas Técnicas da Cartografia Nacional, através do Padrão de Exatidão Cartográfica (PEC) para a escala 1:25.000, classe A, do mapeamento sistemático brasileiro. Na etapa de correção geométrica são consideradas as abordagens do modelo rigoroso do sensor e do modelo generalizado com uso de Rational Polynomial Coefficients (RPCs). Os pontos de controle usados na correção geométrica, bem como para avaliação global da acurácia posicional de ortoimagens e MDSs, foram determinados por posicionamento GPS relativo estático. As avaliações locais, visando análise do comportamento dos MDSs segundo diferentes morfologias, são realizadas a partir de pontos de controle determinados por posicionamento GPS relativo cinemático, em superfícies de baixa declividade e em encostas de anfiteatros. Os resultados alcançados em nível global sinalizam que a modelagem geométrica utilizada, o número de pontos de controle considerados, assim como estratégias de correlação e espaçamento da grade influenciam a acurácia altimétrica dos MDSs, relativamente ao padrão de acurácia esperado. Os experimentos realizados para ortorretificar as imagens nadir com emprego de MDSs previamente selecionados, demonstram que variações quanto a esses fatores, além de acurácias altimétricas diferentes, não influenciam a qualidade planimétrica esperada para as ortoimagens, retratando, portanto, o mesmo padrão de qualidade planimétrica para os MDSs empregados na ortorretificação. Os testes estatísticos quanto à tendência e precisão confirmam a consistência relativa das ortoimagens e MDSs gerados, porém, a maioria desses produtos apresenta tendência, com exceção de alguns casos isolados. Quanto à avaliação local, os resultados indicam que diferentes morfologias influenciam a acurácia dos MDSs relativamente à análise global. De forma geral, áreas com menor declividade apresentam resultados com maior acurácia. As análises locais indicam ainda que a variável declividade, associada a fatores como a falha na correlação e procedimentos de interpolação, proporciona degradação da acurácia altimétrica dos MDSs.
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Utilização de perfis multi-temporais do NDVI/AVHRR no acompanhamento da safra de soja no oeste do Parana / Use of NDVI/AVHRR time-series profiles for soybean crop monitoring in the west of Parana, BrazilEsquerdo, Julio Cesar Dalla Mora, 1977- 16 February 2007 (has links)
Orientador: Jurandir Zullo Junior / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola / Made available in DSpace on 2018-08-08T15:45:15Z (GMT). No. of bitstreams: 1
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Previous issue date: 2007 / Resumo: O principal problema levantado nesta tese é que a ocupação do espaço rural para a produção agropecuária se efetiva sem a devida preocupação com os recursos naturais disponíveis, em especial o solo, e sem o conhecimento das características sócio-econômicas dos produtores. Uma das evidências para essa constatação é que ainda não há estudos suficientes sobre as dinâmicas ambientais e sociais do uso do solo, ocorrendo uma supervalorização da dimensão econômica na exploração dos mesmos. Objetivou-se realizar um estudo do meio físico, através de suas potencialidades e limitações, em sobreposição aos indicadores sócio-econômicos, com vistas a avaliar uma proposta metodológica de planejamento rural para o desenvolvimento sustentável. A partir daí procurou-se quantificar a adequabilidade do uso do solo dos municípios de Aguaí, Mogi Guaçú e Estiva Gerbi, Estado de São Paulo, para os anos de 1981, 1990 e 1997, compondo um banco de dados espaciais multitemporais. A avaliação sócio-econômica foi feita por meio da análise da dinâmica de ocupação e uso dos recursos naturais pelos agricultores, agrupados em setores censitários do IBGE, cujas variáveis e tipologia, georeferrenciadas, compuseram o banco de dados de atributos. A metodologia foi desenvolvida a partir da elaboração do Mapa de Adequabilidade do Uso do Solo dos municípios, empregando-se os Mapas de Aptidão Agrícola e de Uso e Cobertura do Solo, segundo o Método de Avaliação de Aptidão Agrícola, utilizando-se imagens dos satélites Landsat 2 (MSS) e Landsat 5 (TM). Foram também analisadas as transformações no uso dos solos pela tabulação cruzada e índices de exatidão global e Kappa, que indicam o grau de evolução nas mudanças ocorridas no espaço analisado. A caracterização sócio-econômica e tecnológica dos setores censitários foi efetivada por meio da Análise Fatorial de Correspondências Múltiplas (ACM) e da Classificação Hierárquica Ascendente, com os dados do Censo Agropecuário 1995/96. Os resultados da análise física multitemporal permitiram delimitar o histórico agroambiental do uso dos solos, representando a evolução e expansão agropecuária, em relação ao uso e adequabilidade dos mesmos. A análise espaço-temporal do uso intensivo do solo e da adequabilidade indicou uma forte evolução no sentido do aumento da ocupação dos solos, tanto para um uso adequado, quanto para uma sobreutilização. Nos três municípios, percebe-se que, com a intensificação da modernização da agricultura, as terras subutilizadas vão diminuindo, gradativamente de 1981 a 1997, apontando seu decréscimo na direção do desmatamento e/ou substituições das pastagens, para a introdução de culturas anuais e/ou permanentes, de maior valor comercial. Por outro lado, áreas que deveriam estar como reservas para preservação permanente acabam também sendo apropriadas por cultivos mais intensivos, ocorrendo, novamente, uma sobreutilização do solo. Foram definidos quatro tipos de agricultores nos municípios: modernos e diversificados citrícolas capitalizados, criadores descapitalizados de animais e familiares com produção vegetal diversificada. Como resultado final, obteve-se um conjunto de mapas, que traduzem o conhecimento integral dos espaços rurais e a ocupação do território. A metodologia proposta mostrou-se apropriada para o subsídio ao planejamento sócio-ambiental, propiciando elementos para um diagnóstico atualizado e eficaz, no estabelecimento de políticas públicas voltadas ao desenvolvimento rural sustentado / Abstract: The main problem raised in this thesis is that the occupation of the agricultural space for the farming, effectives production without the proper concern with the available natural resources, in special the ground, and without the knowledge of the social and economical characteristics of the producers. One of the causes for this confirmation is that it does not have enough studies yet on the environmental and social dynamic of the use of the land, occurring a supervaluation of the economic dimension in the exploration of agricultural ground. It was aimed to carry through a study of its potentialities and limitations, in overlapping to the social and economical index, with sights to evaluate a methodological proposal of agricultural planning for the sustainable development. Since then, it was tried to quantify the adequateness of the use of lands of the cities of Aguaí, Mogi Guaçú and Estiva Gerbi, State of São Paulo, for the years of 1981, 1990 and 1997, composing a multisecular space data base. The social and economical evaluation was made by the analysis of the dynamics of occupation and use of the natural resources for the agriculturists, grouped in tax sectors of the IBGE, whose georeferenced variable and typology had composed the bank of attributes. The methodology had as base the elaboration of the Map of Adequateness of the Use of Lands of the cities, using the Maps of Agricultural Aptitude and the Use and Covering of the Ground, according to Method of Classification of Agricultural Aptitude, using images of the satellites Landsat 2 (MSS), Landsat (5 TM) and Landsat 7 (ETM+). Also the transformations in the use of lands for the cross tabulation and index of global exactness and Kappa had been analyzed, that indicate the degree of evolution in the occured changes in the analyzed space. The social, economical and technological characterization of the tax sectors was accomplished by means of the Factorial Analysis of Correspondence (ACM) and the Ascending Hierarchic Classification, with the data of 1995/96 Farming Census. The results of the multisecular physical analysis had allowed to delimit the agro-environmental description of the use of the land, being represented the evolution and farming expansion in relation to the use and adequateness of lands. The analysis space-weather of the intensive use of the ground and the adequateness, indicated one strong evolution in the direction of the increase of the occupation of lands, as much for an adjusted use as for an over-use. In the three cities, it was perceived gradually that, with the intensification of the modernization of agriculture, the underutilized lands diminished, from 1981 to 1997, pointing its decrease in the direction of the deforestation and/or substitutions of the pastures with respect to the introduction of annual and/or permanent cultures of higher commercial value. On the other hand, lands that would have to remain as reserves for permanent preservation also finishing being appropriate for more intense cultivation, occurring, again, an over-use of the lands. Four types of agriculturists in the cities had been defined: modern and diversified, capitalized citrus producers, undercapitalized animal breeders, diversified familial vegetal production. As final result, a set of maps was gotten, aiming at the integral knowledge of the agricultural spaces and the occupation of the territory. The methodology proposal revealed appropriate for the subsidy to the spcial and environmental planning, propitiating elements for a fast, brought up to date and efficient diagnosis, in the establishment of directed public politics to the supported agricultural development / Doutorado / Planejamento e Desenvolvimento Rural Sustentável / Doutor em Engenharia Agrícola
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