149 resultados para Remote sensing images
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When registering spectral radiance from surface targets, digital numbers recorded by the imagery sensor may vary. Such variation causes imperfections on the images coming from aerial surveys. Variation in the image brightness related to the distance from the center of the image is known as the vignetting effect. Correcting this effect aims at achieving an homogeneous image brightness. The purpose of this paper is to present a specific methodology to determine a model in order to minimize this vignette effect based on a model fit by Least Squares Method (LSM), using digital numbers (DN) from shadowed regions. The main hypothesis is that the recorded DN of shadow pixels should be suitable to model the vignetting effect. Considering that the vignetting effect could be modeled as a trend of spatial image variation, a trend surface analysis of a sample of pixels from shadowed regions was carried out. Two approaches were adopted to represent the shadow regions of an image. The first one takes into account the components R, G, B of the aerial image within the visible spectral band, and the second one considers the component I of the HSI image. In order to evaluate the methodology, a study case with a color aerial image was carried out. The findings showed that the best results were obtained by applying the model in the RGB components, which allows to conclude that the vignetting effect can be modeled based on trend surfaces fit on shadow regions DN.
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Pós-graduação em Agronomia (Energia na Agricultura) - FCA
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This paper makes a comparative analysis of results produced by the application of two techniques for the detection and segmentation of bodies in motion captured in images sequence, namely: 1) technique based on the temporal average of the values of each pixel recorded in N consecutive image frames and, 2) technique based on historical values associated with pixels recorded in different frames of an image sequence.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The present study characterizes the physical environment for its fragility and its capacity to support, through geological and geomorphological properties in the study area, concerning primarily with a sustainable environmental planning for the construction and maintenance of buried linear works. The study area is located on a portion of the Paraiba Valley, which is between the latitudes 22 °30' S and 23°00' S and longitudes 44°30' W and 45° 15' W, between cities of Aparecida (SP) and Queluz (SP). The methodology was based in the visual interpretation of TM/Landsat-7 images, using as a criterion the element textural image and its way of organizing space. To do so, it was set five levels of textural density, enabling thus to the partitioning of the area in areas counterparts (Z.H.s). As a result, it was identified 133 Z.H.s. By using the same criterion textural image the following physical properties were classified: Erosion Resistance, Permeability, Plasticity X Brittle, Tropia and Relief Asymmetry for each zone counterpart, and then grouped themselves as they hold all properties equal in Units Geoenvironmental (U.G.s). As a result it was identified 18 U.G.s. The work presents, as a final result, a thematic map with favorable or restrictable sectores to the design of buried linear works. Based on this map, it can be propose traces to buried linear works, analyzing their suitability to the physical environment and reducing the impacts caused to the environment.
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The style of life in the cities deprives the man of the contact with nature. As a way to escape from the turbulent reality of the urban system, the urban planning provides areas that allow the contact between man and nature like botanical gardens, parks, leafy squares, etc. These places, through specific analysis, are also called green areas. Thus, the main purpose of this research is to outline and analyze, through geoprocessing techniques, green areas of Americana, São Paulo considering them as indicators of urban environmental quality. This evaluation will be based on the methodology adapted by Bargos (2010) where products of remote sensing were used (aerial photos and satellite images) and it will be also based on field work and calculation of the amount of green areas. The software ESRI ArcGIS® will be used to create thematic maps connected with city’s green areas. Based on the results achieved in this study, it’s expected to contribute to the government of the city of Americana in order to provide benefits of analysis for decision makers in the context of urban planning aiming an improvement in the urban environmental quality, thus benefiting its entire population
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The area of this work is located along the Northern portion of the Pelotas´s basin. The onshore region extends from the Southern portion São Paulo State to the North of Rio Grande do Sul State, with a total area of 440 530 km ². The objective of the research is to characterize the main geological structures of the outcropping basement in the Paraná Basin and its correlation with the offshore portion of the Pelotas Basin. The characterization was performed through the integration of surface (SRTM images and outcrops) and subsurface data (seismic data and well logs), the method includes the use of remote sensing techniques and seismic interpretation. The main structures to be analyzed are the Tibagi Lineament and the “Torres Syncline in order to verify its influence on the geological evolution and deformation of the basin. As result, it was identified the continuity of the both structures inside the offshore basin (Pelotas Basin); but only the Tibagi Lineament represents an important structural feature in the offshore basin. In this sense, the Tibagi lineament shows a NW-SE direction along the both basins (Pelotas and Paraná) and it is defined by drainages and relief on the continental portion. It was classified as a graben structure limited by normal faults and it also was verified a trend of faults inside the lineament that cuts all the sedimentary package of Itararé Group from Paraná Basin. The Torres syncline is a structure that connects the arches of Ponta Grossa and Rio Grande, showing NW-SE orientation and a low angle dip in the NW direction. Its projection into the Pelotas Basin was not recognized by the methods applied in this work, because a preliminary analyze indicates that its projection corresponds to a structural high inside the Pelotas Basin
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As an effect of the imbalance caused by the damming of rivers and pollution, it has been observed a growing aquatic plants infestation in reservoirs for the generation of electricity. In addition to power generation, these sites have also been used for various other purposes, including recreation, attracting water and navigation. Thus it is important to evaluate these water bodies periodically, in order to verify the leading conditions to the growth of algae, plants and other organisms. In this sense, Remote sensing technology can be a valuable tool for mapping and monitoring the occupation of land in the vicinity of the water body and the optical properties of water, to provide subsidies for the effective management of these aquatic environments. This paper aims to perform the monitoring of the occurrence of aquatic plants in Salto Grande Hydropower Reservoir, located in Americana (SP) and, periodically, map the occupation of land in the vicinity of the water body, through multispectral images taken by sensors on the satellites Landsat series in seven consecutive years: 2004, 2005, 2006, 2007, 2008, 2009 and 2010. The adopted methodological procedure included the images data and the classification of multispectral images to map, every year, the location and extension of the area infested by aquatic plants and the occupation of land
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The metropolitan region of São Paulo is the most populous of the country, this happens because of its great importance in the national economy and the job opportunities that are offered to the population. These factors result in intense population growth and urban expansion, reaching some non-habitable places of the metropolis, as areas of pipelines, which are very important for the transportation of natural gas, oil and its derivatives. Before the population growth of the region, these sites were unoccupied, do not presenting problems for the population. However, with the disorderly occupation is generated great anthropogenic pressure on the pipeline stitches, causing risks to people who are around them. Therefore it is extremely important to monitor the strip of pipelines through products and techniques of remote sensing and geoprocessing, enabling, through high spatial resolution images, identification of objects or phenomena that occur on Earth's surface that can alter the functioning and safety of pipelines. Therefore, this study aims to monitor a stretch of the area of the pipeline mesh GASPAL/OSVAT and Capuava Refinery (RECAP), located on the outskirts of the metropolitan area of São Paulo in the city of Mauá, who suffer great human pressure, proving thus the techniques of remote sensing and geographic information system (GIS) as effective tools for monitoring phenomena occurred in urban areas of great complexity. The monitoring was done by object-based classification applied in orbital images Ikonos II and RapidEye, of high spatial resolution and, image processing, detection of objects, segmentation, classification and editing were developed through the eCognition and ArcGis softwares. To determine the statistical accuracy of the mapping of the land cover of the stretch of pipeline in Maua, the results were analyzed by error matrix... (Complete abstract click electronic access below)
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The implementation of an Export and Processing Zone (ZEPs) brings several benefits to the local, state and federal economy, but often, only socioeconomic factors are considered, apart from several other factors that should be analyzed, such as the environment. In this context of industrialization and the struggle for sustainable development, this work propose to incorporate the environmental variable in the decision process for establishing industrial areas, in particular, the ZPE in the city of Fernandópolis, São Paulo state, Brazil, by examining several physical and environmental factors such as slope intervals, geological features, pedological factors and land use. Developed using a multicriteria analysis, a model has been elaborated, where these factors have received a proportional value according with their importance, supported by a GIS tool (Geographical Information System) and remote sensing products, such as images from CBERS satellite and SRTM radar, showing the suited areas for industrial activities, considering environmental conditions. This model may assist to take better decision about the ZPE implementation area and to reduce the negative environmental impacts that would result of poorly planned locations
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This paper discusses about the use of remote sensing image and processing digital images tools for mapping and assessing the effect on the biomass of the culture of sugar cane in the city of Rio Claro. We used satellite images from CBERS in the passages of 19/04/2009 and 23/09/08, which correspond respectively to the stages where the sugar cane appeared in growing and adult pre-harvest stage. In these images, we applied procedures of digital processing, as the application of the procedures for extending linear contrast, radiometric normalization, Normalized Vegetation Index (NDVI) and pixel by pixel classification by ISOSEG through of the software SPRING. As a result we obtained mapping of the distribution and development stages of the culture of sugar cane in the city of Rio Claro and the mapping of the existing biomass of this culture, showing that the method used to assess the relative effect on biomass in culture of sugar cane was efficient, and that images of low-medium resolution are not the most suitable for the mapping of this culture
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The expansion and growth of towns affect the hydrology of watersheds included in the urban environment, impacting mainly the slopes and river channels. This interference can be in soil waterproofing, the runoff of rainwater, the extinction of surface drainage, the dynamics of flooding processes, etc. For studies concerning the hydrological behavior of watersheds, Remote Sensing techniques have been used to support the acquisition and analysis of data and also to generate new information from the integration of these data. In this context, the study aimed to characterize scenarios and conduct comparative analysis of urban occupation of parts of watershed the Córrego da Servidão, in Rio Claro (SP) and analyze the degree of waterproofing on the ground. With the support of the soil categories of waterproofing listed in Soil Conservation Service (S.C.S / USDA) this analysis was conducted, considering the scenarios of 1958 and 2006, through processes of interpretative analysis of panchromatic and color images aerofotogramétricas. The analysis, data integration and mapping of the watershed area were conducted in an environment of a Geographic Information System (GIS). Maps were obtained to characterize land cover in the watershed, showing the evolution of urban occupation, as well as indicating the densely built and waterproofed
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Different forms of human pressure may occur in the pipeline ranges, due to the large extensions and various configurations of land use, which can pass through the pipelines. Due to the dynamics of these pressures, it is necessary to monitor temporal changes of land use and cover the surface. Under this theme, appears as extremely important to use products and techniques of remote sensing, as they allow the identification of objects of the land surface that may compromise the security and monitoring of the pipeline, and allows the extraction of information conditions on land use at different periods of time. Based on the above, this paper aims to examine in a temporal approach, the process of urban expansion in the municipality of Duque de Caxias, located on the outskirts of the metropolitan area of the state of Rio de Janeiro, as well as settlement patterns characteristic of areas that the changes occurred in the period 1987 to 2010. We used the technique of visual analysis to perform the change detection and the technique of image classification, aimed at monitoring human pressure over a stretch of track pipeline Rio de Janeiro - Belo Horizonte, located in the state of Rio de Janeiro. The stages of work involved the characterization of the study area, urban sprawl and the existing settlement patterns, through the analysis of bibliographic data. The processing of Landsat 5 images and the application of the technique of change detection were performed in three scenes for the years 1987, 1998 and 2010, while the classification process was performed on the image RapidEye for the year 2010. Can be noted an increase in urban area of approximately 22.38% and the change of land cover from natural to built. This growth is concentrated outside to the area of direct influence of the duct, occurring in the area of indirect influence of the enterprise. Regarding the settlement patterns of growth areas, it was observed that these are predominantly
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The transportation of oil through polyducts implies a concern related to safety and environmental impacts they may cause, especially when exposed to risks that affect their integrity. Among the various anthropogenic activities included in this scenario, mining can aggravate, increase the risks and degrade the environment. Since these polyducts go through significant extensions, remote sensing has great applicability as a tool for data acquisition. For this, change detection techniques were used to monitor mining activities in a defined study area in the state of Rio de Janeiro, along the duct ORBEL. The characterization of the study area and the mining activities were developed through bibliographical data. The satellite images processing and the application of change detection technique were performed in two scenes for the years 2002 and 2010. The growth in the mining area was about 6.67 times and it was possible to identify types of extraction involved which can represent direct risks to the pipeline
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The mining of sand, currently, is essential for urban growth, by providing input for the building industry. The consequences of this mining activity to environmental triggers may be severe and irreversible. Among the major impacts caused by sand mining the riparian vegetation removal is detached. The riparian vegetation is essential for balance and maintaining the local ecosystem. For all that had been shown, is possible to verify the importance of environmental studies in areas wich there are mining. This study aimed specially to assess environmental impacts triggered by a mining, located near the headwaters of the stream Mandu, situated in Ajapi, District of Rio Claro-SP. For this purpose, we used remote sensing techniques and GIS to produce thematic maps of slope, pedology, geology, land use and occupation of the soil, and riparian vegetation, using the capabilities of GIS / ArcGIS. The slope map was based on data from the Cartographic IGC 1979, scale 1:10,000. For the production of pedological and geological maps were used Semi-Detailed soil survey of the state of São Paulo, 1981 (1:100,000) and the Geological Map of Zaine (1994), scale 1:50,000, respectively. Since the maps of Use and Land Occupation and Riparian Forest were obtained by visual interpretation of the image of CBERS 2010 following the merger between the HRC and CCD images. From these mappings, and through multi-criteria analysis, map of susceptibility to erosion was made, which supported the environmental assessment of the studied area, indicating susceptible and unsuitable areas for the deployment of economic activities and urban sprawl. This study serves as a model can be replicated in other watersheds, assisting in the proper use planning and land use, aiming at the rational use of natural resources