clarke@utcsri.UUCP (Jim Clarke) (11/25/86)
(GB = Galbraith Building, 35 St. George Street)
A.I. SEMINAR, Tuesday, December 2, 3 pm, GB 119
Professor Michael Leyton
Computer Science, SUNY
"A Process Grammar for Shape"
A computational theory is offered of the way in which process-history
is recovered from shape. It is claimed that curvature extrema are cru-
cially used in the inference of processes from shape, and rules are
developed that formalize the inference procedure. We then establish a
process-grammar of only six types of operations to express the relationship
between any two given shapes such that one shape is represented as a later
stage in the development of the other; i.e. one shape is described as the
extrapolation of processes inferred in the other under the above inference
rules. More formally, a deformation is expressed as a transformation of
process-records - a technique reminiscent of Chomsky's description of
linguistic transformations in terms of transitions between phrase-structure
trees. In the present case, our process-grammar has the psychological role
of explaining the curvature extrema in terms of a sequence of psychologi-
cally meaningful deformations. We find that the grammar thereby stratifies
shape-space into several intersecting systems of strata, where each
strata-system represents a particular process-history of successive modifi-
cation.
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Jim Clarke -- Dept. of Computer Science, Univ. of Toronto, Canada M5S 1A4
(416) 978-4058
{allegra,cornell,decvax,linus,utzoo}!utcsri!clarke