48,990 research outputs found
A Framework for Image Segmentation Using Shape Models and Kernel Space Shape Priors
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Partial Perception and Approximate Understanding
What is discussed in the present paper is the assumption concerning a human narrowed sense of perception of external world and, resulting from this, a basically approximate nature of concepts that are to portray it. Apart from the perceptual vagueness, other types of vagueness are also discussed, involving both the nature of things, indeterminacy of linguistic expressions and psycho-sociological conditioning of discourse actions in one language and in translational contexts. The second part of the paper discusses the concept of conceptual and linguistic resemblance (similarity, equivalence) and discourse approximating strategies and proposes a Resemblance Matrix, presenting ways used to narrow the approximation gap between the interacting parties in monolingual and translational discourses
Tracking the dynamics of translation and absolute orientation of a sphere in a turbulent flow
We study the 6-dimensional dynamics -- position and orientation -- of a large
sphere advected by a turbulent flow. The movement of the sphere is recorded
with 2 high-speed cameras. Its orientation is tracked using a novel, efficient
algorithm; it is based on the identification of possible orientation
`candidates' at each time step, with the dynamics later obtained from
maximization of a likelihood function. Analysis of the resulting linear and
angular velocities and accelerations reveal a surprising intermittency for an
object whose size lies in the integral range, close to the integral scale of
the underlying turbulent flow
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