Isometry
Mostrando 13-24 de 28 artigos, teses e dissertações.
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13. Semigroups and control in semi-simple grups over local fields / Semigrupos e controle em grupos semisimples sobre corpos locais
Let G be a almost-simple, simply connected and connected Lie group over a local field and S a subsemigroup with non-empty interior. Studying the action of the regular hyperbolic elements in the interior of S on the flag manifold G / P and on the associated euclidean building, we prove the existence and uniqueness of the invariant control set. Moreover we pro
Publicado em: 2006
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14. Reflexões e numero de cobertura de arvores homogeneas e grupos de automorfismos de arvores semi-homogeneas
Let G be a homogeneous tree and Aut(G) its group of automorphism. An automorphism Î Aut(G) is said to be even if d(f(x),x) º0 mod 2 for every vertex x Î G of , where d(.,.) is the canonical distance function defined by the minimum length of paths connecting the vertices. The set Aut+(G) of all even automorphism is a subgroup of index 2 in Aut(G). We defin
Publicado em: 2006
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15. Length-weight relationship and condition factor of Micropogonias furnieri (Desmarest) (Perciformes, Sciaenidae) in the Sepetiba Bay, Rio de Janeiro State, Brazil
The length-weight relationship and spatial, temporal and ontogenetic changes in the condition factor of Micropogonias furnieri (Desmarest, 1823) were analyzed, from samples collected between October 1998 and September 1999, in the Sepetiba Bay, a coastal area with a wide communication with the sea (22º54'-23º04'S, 43º34'-44º10'W) at Southeast Brazil. The
Revista Brasileira de Zoologia. Publicado em: 2003-12
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16. Efeito da estimulação eletrica nervosa transcutanea sobre a atividade eletromiografica dos musculos da mastigação em individuos portadores de desordem temporomandibular
Temporomandibular disorder (TMD) is characterized by severa I signs and symptoms, among which are pain and changes in the electromyographic activity of the masticatory muscles. Thus, the objective of this work, which is composed of two articles, is 1) to identífy the alterations in the electromyographic activity of TMD individuais at rest and isometry situa
Publicado em: 2002
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17. Reflexões, isometrias e arvores
We define a reflection in a graph as an involutive automorphism whose set of fixed points is a complete geodesic. Using this concept, we prove that the product of two such reflections is an eliptic isometry if and only if its sets of fixed points has nonempty intersection. Moreover, for the case of a regular tree of valency 4k, we prove that the topological
Publicado em: 2002
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18. Alguns aspectos da geometria riemanniana das variedades de Hilbert
The aim of this work is to formalize the local theory of infinite dimensional Riemannian manifold and to study the geometry/ topology when the sectional curvature is bounded by two positive constant. We compare this situation with the finite dimensional case and emphasize the difference. The local theory was already developed since 1960, so we describe, brie
Publicado em: 2002
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19. Caracterizações algebrica e geometrica dos codigos propelineares
In this dissertation we consider the class of propelinear codes as well as the subclass of translation invariant propelinear codes. From the algebraic point of view these classes of codes are shown to be subgroups of the semidirect product of Z_ by Sn whereas from the geometric point of view they are shown to be codes over isometry groups of a given alphabet
Publicado em: 2000
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20. Calculus of twisted vertex operators
Starting from an arbitrary isometry of an arbitrary even lattice, twisted and shifted vertex operators are introduced. Under commutators, these operators provide realizations of twisted affine Lie algebras. This construction, generalizing a number of known ones, is based on a self-contained “calculus.”
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21. SCHWARZ'S LEMMA IN NORMED LINEAR SPACES*
In this paper we show that any Fréchet holomorphic function mapping the open unit ball of one normed linear space into the closed unit ball of another must be a linear mapping if the Fréchet derivative of the function at zero is a surjective isometry. From this fact we deduce a Banach-Stone theorem for operator algebras which generalizes that of R. V. Kadi
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22. Hessian eigenmaps: Locally linear embedding techniques for high-dimensional data
We describe a method for recovering the underlying parametrization of scattered data (mi) lying on a manifold M embedded in high-dimensional Euclidean space. The method, Hessian-based locally linear embedding, derives from a conceptual framework of local isometry in which the manifold M, viewed as a Riemannian submanifold of the ambient Euclidean space ℝn,
The National Academy of Sciences.
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23. A Gauss measure on the set of interval exchange transformations
An interval exchange transformation is a piece-wise order-preserving isometry of a finite interval. In previous works the author has reduced certain questions about interval exchange transformations to questions about the ergodic behavior of a related class of transformations, with domain the body of all interval exchange transformations. The latter question
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24. ε factor of representations of classical groups
We let G be the isometry group of a nondegenerate symmetric or skew-symmetric form h on a space V over some local or global field K [i.e., G = U(V, h)]. We let LG be the L group of Go = the identity component of G and r be the natural representation of this group. We develop here a theory of L functions and ε factors attached to this r. In particular we dev