In general, two quadric surface intersect in a space quartic curve. However, the intersection frequently degenerates to a collection of plane curves. Degenerate cases are frequent in geometric/solid modeling because degeneracies are often required by design. Their detection is important because degenerate intersections can be computed more easily and allow… (More)
We present an algorithm for computing the convex hull of freeform rational surfaces. The convex hull problem is reformulated as one of finding the zero-sets of polynomial equations; using these zero-sets we characterize developable surface patches and planar patches that belong to the boundary of the convex hull.
We propose development of evidence-based methods to guide clinical intervention in neurobehavioral syndromes based on categorization of individuals using both behavioral measures and quantification of the EEG (qEEG). Review of a large number of clinical EEG and qEEG studies suggests that it is plausible to identify a limited set of individual profiles that… (More)
We present a method for constructing tensor product Bezier surfaces from contour (cross-section) data. Minimal area triangulations are used to guide the surface construction , and the final surface reflects the optimality of the triangulation. The resulting surface differs from the initial triangulation in two important ways: it is smooth (as opposed to the… (More)
In general, two quadric surfaces intersect in a space quartic curve. However, the intersection curve frequently degenerates to a collection of plane curves. These degenerate cases introduce problems into the general intersection algorithms and are difficult to implement in a reliable way. In this paper, we investigate this problem for natural quadrics.… (More)