Results 21 to 30 of about 5,426 (162)
Interferometric apodization by homothety – I. Optimization of the device parameters [PDF]
Monthly Notices of the Royal Astronomical Society, 2023 ABSTRACT This study is focused on the very high dynamic imaging field, specifically the direct observation of exoplanetary systems. The coronagraph is an essential technique for suppressing the star’s light, making it possible to detect an exoplanet with a very weak luminosity compared to its host star. Apodization improves the rejection
Jamal Chafi +6 more
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Interferometric apodization by homothety – II. Experimental validation [PDF]
Monthly Notices of the Royal Astronomical Society, 2023 ABSTRACT This work presents the results of experimental laboratory tests on the apodization of circular and rectangular apertures using the Interferometric Apodization by Homothety (IAH) technique. The IAH approach involves splitting the amplitude of the instrumental PSF into two equal parts.
Jamal Chafi +6 more
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On the homothety conjecture [PDF]
Indiana University Mathematics Journal, 2011 Let $K$ be a convex body in $\bbR^n$ and $\d>0$. The homothety conjecture asks: Does $K_{\d}=c K$ imply that $K$ is an ellipsoid? Here $K_{\d}$ is the (convex) floating body and $c$ is a constant depending on $\d$ only. In this paper we prove that the homothety conjecture holds true in the class of the convex bodies $B^n_p$, $1\leq p\leq \infty ...
Elisabeth M. Werner, Deping Ye
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Homothety Curvature Homogeneity and Homothety Homogeneity [PDF]
Annals of Global Analysis and Geometry, 2014 This article supersedes arXiv:1309 ...
Eduardo García‐Río +2 more
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Homotheties and incidences [PDF]
Discrete Mathematics, 2018 We consider problems involving rich homotheties in a set S of n points in the plane (that is, homotheties that map many points of S to other points of S). By reducing these problems to incidence problems involving points and lines in R^3, we are able to obtain refined and new bounds for the number of rich homotheties, and for the number of distinct ...
Dror Aiger, Micha Sharir
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Some Properties of Ruled Surfaces under Homothety in E3 [PDF]
Mathematical and Computational Applications, 2002 It is clearly that, If f : E3→E3 is a homothety and \(\varphi\) is a surface in three dimensional Euclidean space E3, \(f(\varphi) = \overline{\varphi}\) is also a surface in E3. In this paper, the surface \(\varphi\) has been taken a ruled surface, specially. It was shown that image surface \(f(\varphi) = \overline{\varphi}\) has been a ruled surface,
Emîn Kasap, Salîm Yüce, N. Kuruoğlu
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Homotheties and topology of tangent sphere bundles [PDF]
Journal of Geometry, 2014 15 pages, to appear in Journal of ...
Rui Albuquerque
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Action of Non Abelian Group Generated by Affine Homotheties on R^n [PDF]
, 2010 In this paper, we study the action of non abelian group G generated by affine homotheties on R^n. We prove that G satisfies one of the following properties: (i) there exist a subgroup F_{G} of R\{0} containing 0 in its closure, a G-invariant affine subspace E_{G} of R^n and a in E_{G} such that for every x in R^n the closure of the orbit G(x) is equal ...
Adlene Ayadi, Yahya N'Dao
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Topological Homotheties on Compact Metrizable Spaces [PDF]
Canadian Journal of Mathematics, 1968 Notation and definitions.Definition 1. Let (X, ρ) be a metric space and ϕ: X → X a continuous self-mapping of X. We shall call ϕ and α-contraction on (X, ρ) if and only if α ϵ [0,1) and . We shall call ϕ an α-homothety on (X, ρ) if and only if α > 0 and .
Ludvík Janoš
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The Return of Homothety in den Mathematical Contests
, 2008 Sandra Zabarovska
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