Results 1 - 10 of 3,033

On active contour models and balloons

by D. Cohen - CVGIP: Image
"... The use.of energy-minimizing curves, known as “snakes, ” to extract features of interest in images has been introduced by Kass, Witkhr & Terzopoulos (Znt. J. Comput. Vision 1, 1987,321-331). We present a model of deformation which solves some of the problems encountered with the original method. ..."
Abstract - Cited by 588 (43 self) - Add to MetaCart
The use.of energy-minimizing curves, known as “snakes, ” to extract features of interest in images has been introduced by Kass, Witkhr & Terzopoulos (Znt. J. Comput. Vision 1, 1987,321-331). We present a model of deformation which solves some of the problems encountered with the original method

A Borsuk theorem on homotopy types

by Andrzej Trybulec - Journal of Formalized Mathematics , 1991
"... Summary. We present a Borsuk’s theorem published first in [1] (compare also [2, pages 119–120]). It is slightly generalized, the assumption of the metrizability is omitted. We introduce concepts needed for the formulation and the proofs of the theorems on upper semi-continuous decompositions, retrac ..."
Abstract - Cited by 108 (6 self) - Add to MetaCart
, retracts, strong deformation retract. However, only those facts that are necessary in the proof have been proved.

THE LOOP GROUP AND THE COBAR CONSTRUCTION

by Kathryn Hess, Andrew Tonks , 903
"... Abstract. We prove that for any 1-reduced simplicial set X, Adams ’ cobar construction ΩCX on the normalised chain complex of X is naturally a strong deformation retract of the normalised chains CGX on the Kan loop group GX. In order to prove this result, we extend the definition of the cobar constr ..."
Abstract - Cited by 4 (3 self) - Add to MetaCart
Abstract. We prove that for any 1-reduced simplicial set X, Adams ’ cobar construction ΩCX on the normalised chain complex of X is naturally a strong deformation retract of the normalised chains CGX on the Kan loop group GX. In order to prove this result, we extend the definition of the cobar

BLOW-ANALYTIC RETRACTION ONTO THE CENTRAL FIBRE

by Adam Parusiński , 1997
"... Abstract. Let X be a complex analytic space and let f: X → C be a proper complex analytic function with nonsingular generic fibres. By adapting the blowanalytic methods of Kuo we construct a retraction of a neighbourhood of the central fibre f −1 (0) onto f −1 (0). Our retraction is defined by the f ..."
Abstract - Cited by 2 (1 self) - Add to MetaCart
parameter deformation of X0, that is f −1 (0) = X0. We call X0 the central fibre of f. The pair X, X0 can be triangulated, and hence X0 is a strong deformation retract of its neighbourhood in X. Thus shrinking X, if necessary, we may assume

FROM LIE THEORY TO DEFORMATION THEORY AND QUANTIZATION

by Lucian M. Ionescu , 2008
"... Deformation Theory is a natural generalization of Lie Theory, from Lie groups and their linearization, Lie algebras, to differential graded Lie algebras and their higher order deformations, quantum groups. The article focuses on two basic constructions of deformation theory: the universal solution o ..."
Abstract - Add to MetaCart
of Maurer-Cartan Equation (MCE), which plays the role of the exponential of Lie Theory, and its inverse, the Kuranishi functor, as the logarithm. The deformation functor is the gauge reduction of MCE, corresponding to a Hodge decomposition associated to the strong deformation retract data. The above

Moon: Mathematical theory of medial axis transform

by Hyeong In Choi, Sung Woo Choi, Hwan Pyo Moon - Pacific J. Math , 1997
"... The medial axis of a plane domain is defined to be the set of the centers of the maximal inscribed disks. It is essentially the cut loci of the inward unit normal bundle of the boundary. We prove that if a plane domain has finite number of boundary curves each of which consists of finite number of r ..."
Abstract - Cited by 98 (9 self) - Add to MetaCart
of the domain. We also analyze various continuity and regularity results in detail, and show that the medial axis is a strong deformation retract of the domain which means in the practical sense that it retains all the topological informations of the domain. We also obtain parallel results for the medial axis

Nonarchimedean geometry of Witt vectors, preprint (2010) available at http://math.mit.edu/~kedlaya/papers

by Kiran S. Kedlaya
"... Let R be a perfect Fp-algebra, equipped with the trivial norm. Let W (R) be the ring of p-typical Witt vectors over R, equipped with the p-adic norms. We prove that via the Teichmüller map, the nonarchimedean analytic space (in the sense of Berkovich) associated to R is a (strong) deformation retrac ..."
Abstract - Cited by 8 (6 self) - Add to MetaCart
Let R be a perfect Fp-algebra, equipped with the trivial norm. Let W (R) be the ring of p-typical Witt vectors over R, equipped with the p-adic norms. We prove that via the Teichmüller map, the nonarchimedean analytic space (in the sense of Berkovich) associated to R is a (strong) deformation

Foldings and Deformation Retract of Hyperhelix

by A. E. El-ahmady, E. Al-hesiny
"... Abstract: Our aim in the present study is to introduce and study new types of retractions of hyperhelix in Minkowski space. Types of the deformation retracts of hyperhelix in Minkowski space were discussed. The relations between the foldings and the deformation retracts of hyperhelix in Minkowski sp ..."
Abstract - Cited by 1 (1 self) - Add to MetaCart
Abstract: Our aim in the present study is to introduce and study new types of retractions of hyperhelix in Minkowski space. Types of the deformation retracts of hyperhelix in Minkowski space were discussed. The relations between the foldings and the deformation retracts of hyperhelix in Minkowski

Foldings and Deformation Retractions of Hypercylinder

by A. E. El-ahmady, N. Al-hazmi
"... Our aim in the present work is to introduce and study new types of retractions of hypercylinder. Types of the deformation retracts of hypercylinder are presented. The relations between the folding and the deformation retract of hypercylinder are deduced.Types of minimal retractions of hypercylinder ..."
Abstract - Add to MetaCart
Our aim in the present work is to introduce and study new types of retractions of hypercylinder. Types of the deformation retracts of hypercylinder are presented. The relations between the folding and the deformation retract of hypercylinder are deduced.Types of minimal retractions of hypercylinder

Permanent Scatterers in SAR interferometry

by Ro Ferretti, Claudio Prati, Fabio Rocca - IEEE Transactions on Geosci- ence and Remote Sensing
"... Abstract—Temporal and geometrical decorrelation often pre-vents SAR interferometry from being an operational tool for sur-face deformation monitoring and topographic profile reconstruc-tion. Moreover, atmospheric disturbances can strongly compro-mise the accuracy of the results. In this paper, we pr ..."
Abstract - Cited by 222 (10 self) - Add to MetaCart
Abstract—Temporal and geometrical decorrelation often pre-vents SAR interferometry from being an operational tool for sur-face deformation monitoring and topographic profile reconstruc-tion. Moreover, atmospheric disturbances can strongly compro-mise the accuracy of the results. In this paper, we
Results 1 - 10 of 3,033