12 research outputs found
Assessment of SAR Image Filtering using Adaptive Stack Filters
Stack filters are a special case of non-linear filters. They have a good
performance for filtering images with different types of noise while preserving
edges and details. A stack filter decomposes an input image into several binary
images according to a set of thresholds. Each binary image is then filtered by
a Boolean function, which characterizes the filter. Adaptive stack filters can
be designed to be optimal; they are computed from a pair of images consisting
of an ideal noiseless image and its noisy version. In this work we study the
performance of adaptive stack filters when they are applied to Synthetic
Aperture Radar (SAR) images. This is done by evaluating the quality of the
filtered images through the use of suitable image quality indexes and by
measuring the classification accuracy of the resulting images
A user friendly statistical system for polarimetric SAR Image classification.
En este artículo se presenta un sistema para la clasificación de imágenes SAR polarimétricas. Este sistema utiliza información contextual a través de un modelo Markoviano para las clases, además de modelos estadísticos para los datos. El sistema fue desarrollado pensando en el usuario y, por lo tanto, está íntegramente basado en interfaces gráficas. Toda vez que el usuario trata de activar una operación inválida, el sistema le informa la secuencia correcta de pasos. La funcionalidad del sistema se verifica clasificando áreas de cultivo, en una imagen SIR-C/X-SAR
Naming Our Concerns about Neuroscience: A Review of Bennett and Hacker's Philosophical Foundations of Neuroscience
Bennett and Hacker use conceptual analysis to appraise the theoretical language of modern cognitive neuroscientists, and conclude that neuroscientific theory is largely dualistic despite the fact that neuroscientists equate mind with the operations of the brain. The central error of cognitive neuroscientists is to commit the mereological fallacy, the tendency to ascribe to the brain psychological concepts that only make sense when ascribed to whole animals. The authors review how the mereological fallacy is committed in theories of memory, perception, thinking, imagery, belief, consciousness, and other psychological processes studied by neuroscientists, and the consequences that fallacious reasoning have for our understanding of how the brain participates in cognition and behavior. Several behavior-analytic concepts may themselves be nonsense based on thorough conceptual analyses in which the criteria for sense and nonsense are found in the ways the concepts are used in ordinary language. Nevertheless, the authors' nondualistic approach and their consistent focus on behavioral criteria for the application of psychological concepts make Philosophical Foundations of Neuroscience an important contribution to cognitive neuroscience
Parameter estimation of G0 distribution based on improved recursive expectation–maximisation method for clutter modelling
Inscrições de si: da porta de banheiro ao chat
Writing pervades human history, from rupestrian inscriptions to internet. Although supports change – walls, papyrus, parchments, tiles, papers, computer monitors – there remains a register, which transports human being beyond its own existence and which, precisely, renders it existing. In this thesis, I argue that restroom graffiti, apocryphal and ephemeral by their nature, are a link of the chain that identifies human being as the one who is capable of writing. It is an entity that can be figured out through its marks. Without aiming to interpret inscriptions, I restrict myself to observing that a great amount of impressions prefer to be revealed on the subversive support of the cell defined by the restroom door. And that the freedom of being anonymous that characterizes that door is kept when its contents are transposed to internet chatsSubmitted by Rogele Pinheiro ([email protected]) on 2018-01-17T16:36:01Z
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Previous issue date: 2005A escrita permeia a história da humanidade desde as inscrições rupestres até a internet. Embora mudem os suportes – paredes, papiros, pergaminhos, cerâmica, papel, o monitor de um computador –, permanece um registro que transporta o ser humano para além de sua própria existência e que, justamente, faz com que passe a existir. Defendo a idéia, nesta dissertação, de que os grafitos de porta de banheiro, apócrifos e efêmeros por natureza, são elo na corrente que identifica o ser humano como ser que é capaz de escrever. Ele é uma entidade que pode ser descoberta por suas marcas. Sem buscar interpretar as inscrições, atenho-me a observar que uma extensa quantidade de impressões prefere ser revelada no suporte subversivo da célula que a porta de banheiro encerra. E que a liberdade desta mesma porta de aparecer anônima se mantém quando seus conteúdos são transportados para a internet, para as salas de bate-papo
Constant false alarm rate detection method in polarimetric synthetic aperture radar imagery based on whitening filter under inverse beta distribution
Simulated multipolarized MAPSAR images to distinguish agricultural crops
Many researchers have shown the potential of Synthetic Aperture Radar (SAR) images for agricultural applications, particularly for monitoring regions with limitations in terms of acquiring cloud free optical images. Recently, Brazil and Germany began a feasibility study on the construction of an orbital L-band SAR sensor referred to as MAPSAR (Multi-Application Purpose SAR). This sensor provides L-band images in three spatial resolutions and polarimetric, interferometric and stereoscopic capabilities. Thus, studies are needed to evaluate the potential of future MAPSAR images. The objective of this study was to evaluate multipolarized MAPSAR images simulated by the airborne SAR-R99B sensor to distinguish coffee, cotton and pasture fields in Brazil. Discrimination among crops was evaluated through graphical and cluster analysis of mean backscatter values, considering single, dual and triple polarizations. Planting row direction of coffee influenced the backscatter and was divided into two classes: parallel and perpendicular to the sensor look direction. Single polarizations had poor ability to discriminate the crops. The overall accuracies were less than 59 %, but the understanding of the microwave interaction with the crops could be explored. Combinations of two polarizations could differentiate various fields of crops, highlighting the combination VV-HV that reached 78 % overall accuracy. The use of three polarizations resulted in 85.4 % overall accuracy, indicating that the classes pasture and parallel coffee were fully discriminated from the other classes. These results confirmed the potential of multipolarized MAPSAR images to distinguish the studied crops and showed considerable improvement in the accuracy of the results when the number of polarizations was increased