Illusory contours are invoked by the visual system to account for otherwise inexplicable gaps in the image. We report three sets of novel observations on illusory contours. First, when an illusory square is superimposed on a checkerboard pattern there is a considerable enhancement of the contours so long as they are exactly coincident with the borders of the checks. If the checks are misaligned...

Active contours (also known as snakes) have shown their ability to introduce regularity on image segmentation. In contrast with level-set approaches, the active techniques based a contour parameterization are able maintain initial topology of area interest. For this reason, it has been used in recent medical research for diaphragm Most on-line codes 2D/3D segmentation, well built-in Matlab tool...

In this paper, we analyze the electrostatic charge distribution on arbitrarily shaped conductor surfaces. Following a perturbative approach, derive an approximate analytical formulation of problem. We start from known case conducting ellipsoid, adopt deformed ellipsoidal coordinate system, and search for zero-order approximated solution also focus arbitrary-shaped thin foils, showing that densi...