@Article{ValerianoMelSarNegPal:2002:FoBaTo,
               author = "Valeriano, M{\'a}rcio de Morisson and Melo, Andr{\'e} Ricardo de 
                         and Sarraipa, Ludmila Alexandra dos Santos and Negreiros, Ivan 
                         Paulo Mendes and Pallone Filho, Wander",
          affiliation = "IAC and CAT and FEAGRI/Unicamp",
                title = "Forma{\c{c}}{\~a}o de base topogr{\'a}fica digital 
                         (1:1.000.000) do Estado de S{\~a}o Paulo com dados RADARSAT-1 / 
                         Constructing a digital topographical database (1:1.000.000) for 
                         state of S{\~a}o Paulo with RADARSAT-1 data. RADARSAT-",
              journal = "Acta Scientiarum - Technology",
                 year = "2002",
               volume = "24",
               number = "6",
                pages = "1825--1831",
             keywords = "GEOPROCESSAMENTO, RADARSAT-1, topografia, georefer{\^e}ncia, 
                         corre{\c{c}}{\~a}o de artefatos , geoprocessing, RADARSAT-1, 
                         topography, georeference, correction of artifacts.",
             abstract = "Dados do sensor RADARSAT-1 foram preparados para geoprocessamento 
                         na escala: 1:1.000.000 do Estado de S{\~a}o Paulo. A 
                         prepara{\c{c}}{\~a}o consistiu na georrefer{\^e}ncia da imagem, 
                         corre{\c{c}}{\~a}o de artefatos e avalia{\c{c}}{\~a}o da 
                         exatid{\~a}o planim{\'e}trica e altim{\'e}trica. A base 
                         topogr{\'a}fica digital formada apresenta resolu{\c{c}}{\~a}o 
                         de 0,005º. Foram observados artefatos relacionados {\`a} 
                         presen{\c{c}}a de torres de antenas, no oeste paulista, 
                         desenvolvendo-se uma metodologia de processamento digital para sua 
                         remo{\c{c}}{\~a}o. Ao fim da prepara{\c{c}}{\~a}o, as imagens 
                         de altimetria corrigida apresentam erro posicional m{\'e}dio 
                         inferior a 2 km. O erro altim{\'e}trico m{\'e}dio (em torno de 
                         75 m), calculado com amostragem da altimetria sobre as cartas 
                         topogr{\'a}ficas, foi explicado, entre outros fatores, pela 
                         combina{\c{c}}{\~a}o dos erros posicionais com a 
                         distribui{\c{c}}{\~a}o da declividade. Apesar da ligeira 
                         dispers{\~a}o dos dados, a correla{\c{c}}{\~a}o encontrada 
                         entre as cotas altim{\'e}tricas correspondentes da imagem e dos 
                         mapas, com coeficiente de determina{\c{c}}{\~a}o de r2 =0,90, 
                         n{\~a}o indicou necessidade de ajustes sistem{\'a}ticos na 
                         imagem. RADARSAT-1 topographical data were fed into a topografical 
                         database of the state of S{\~a}o Paulo for geoprocessing in 
                         1:1,000,000 scale. The process consisted of georeferering, 
                         correction of artifacts and evaluation of planimetric and 
                         altimetric accuracy. The topographical digital database was 
                         structured 0.005º in a resolution grid. Image artifacts, related 
                         to the presence of antenna towers, were abserved in the west of 
                         S{\~a}o Paulo and a method of digital processing was sucessfully 
                         developed for their supression. The resulting altimetric images 
                         presented mean positional error less than 2 km. The mean 
                         altimetric error (around 75m), calculated by cartographically 
                         sampling elevation data, was explained by the combination of the 
                         positional errors with the slope angle distribution, among other 
                         effects. Despite a slight data dispersion, the correlation between 
                         the elevation of both image and topographical maps, with 
                         determination coefficient of r2=0,90, did not indicate the need 
                         for systematic fits on the images.",
           copyholder = "SID/SCD",
                 issn = "1807-8664",
        urlaccessdate = "11 maio 2024"
}