John Hebert da Silva Felix

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BACKGROUND The effects of nasal continuous positive airway pressure (CPAP) on the lung parenchyma of patients with COPD, to our knowledge, have never been assessed by high-resolution CT (HRCT) scanning. METHODS HRCT scans were obtained at the apex, hilum, and basis of the lungs at functional residual capacity while on spontaneous respiration and at the(More)
Active contours are image segmentation methods that minimize the total energy of the contour to be segmented. Among the active contour methods, the radial methods have lower computational complexity and can be applied in real time. This work aims to present a new radial active contour technique, called pSnakes, using the 1D Hilbert transform as external(More)
Objective: To present a locally developed system of computer vision for use with HRCT images, designated SIStema para a Detecção e a quantificação de Enfisema Pulmonar (SISDEP, System to Detect and Quantify Pulmonary Emphysema), and to compare this system with a freeware system tool. Methods: Thirty-three HRCT images scanned at the apex, hilum and base of(More)
OBJECTIVE To present a locally developed system of computer vision for use with HRCT images, designated SIStema para a Detecção e a quantificação de Enfisema Pulmonar (SISDEP, System to Detect and Quantify Pulmonary Emphysema), and to compare this system with a freeware system tool. METHODS Thirty-three HRCT images scanned at the apex, hilum and base of(More)
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