The induction of nonveridical slant and the perception of shape.

The Induction of Nonveridical Slant and the Perception of Shape J

Koffka's (1935, pp. 224-235) explanation of shape-constancy is based on the assumption of an invariant linkage between slant and shape. Koffka's hypothesis has been formulated in the following way by Beck and Gibson (1955): "A retinal projection of a given form determines a unique relation of apparent shape to apparent slant" (p. 126). The invariance hypothesis requires that perceived shape var...

Shape Operator of Slant Submanifolds in Kenmotsu Space Forms

Dominance of Orientation over Frequency in the Perception of 3-D Slant and Shape

In images of textured three-dimensional surfaces, pattern changes can be characterized as changes in orientation and spatial frequency, features for which neurons in primary visual cortex are classically selective. Previously, we have demonstrated that correct 3-D shape perception is contingent on the visibility of orientation flows that run parallel to the surface curvature. We sought to deter...

ON OPTIMAL NOZZLE SHAPES OF GAS-DYNAMIC LASERS

Pontryagin's principle is used to study the shape of the supersonic part of the nozzle of a carbon dioxide gas-dynamic laser whose gain is maximal. The exact shape is obtained for the uncoupled approximation of Anderson's bimodal model. In this case, if sharp corners are allowed, the ceiling of the supersonic part consists of a slant rectangular sheet followed by a horizontal one; otherwise...

Generalization of general helices and slant helices

In this work, we use the formal definition of $k$-slant helix cite{ali2} to obtain the intrinsic equations as well as the position vector for emph{slant-slant helices} which a generalization of emph{general helices} and emph{slant helices}. Also, we present some characterizations theorems for $k$-slant helices and derived, in general form, the intrinsic equations for such curves. Thereafter, fr...