Results 11 to 20 of about 14,552 (202)
Frontiers in Plant Science, 2022 Cultivated sunflower holds a very narrow genetic base and the efficient utilization of available genetic diversity is very important for a successful breeding program.
Danish Ibrar +15 more
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Lines of Principal Curvature on Canal Surfaces in R^3
Anais da Academia Brasileira de Ciencias, 2006 11 ...
Garcia, Ronaldo +2 more
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Curvature lines on orthogonal surfaces of R3 and Joachimsthal Theorem
Civilizar, 2005 In this paper is studied, as a complement of Joachimsthal theorem, the behavior of curvature lines near a principal cycle common to two orthogonal surfaces.
Ronaldo A. Garcia
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A metric property of umbilic points
Anais da Academia Brasileira de Ciências, 2003 In the space of cubic forms of surfaces, regarded as a G-space and endowed with a natural invariant metric, the ratio of umbilic points with a negative index to those with a positive index is evaluated in terms of the asymmetry of the metric, defined ...
Ronaldo Garcia, Jorge Sotomayor
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Surfaces around closed principal curvature lines, an inverse problem [PDF]
, 2010 Given a non circular spacial closed curve whose total torsion is an integer multiple of $2π$, we construct a germ of a smooth surface that contains it as a hyperbolic principal cycle.
Garcia, R., Mello, L. F., Sotomayor, J.
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On four dimensional Dupin hypersurfaces in Euclidean space
Anais da Academia Brasileira de Ciências, 2003 Dupin hypersurfaces in five dimensional Euclidean space parametrized by lines of curvature, with four distinct principal curvatures, are considered. A generic family of such hypersurfaces is locally characterized in terms of the principal curvatures and ...
CARLOS M. C. RIVEROS, KETI TENENBLAT
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Shear behavior of coarse aggregates for dam construction under varied stress paths
Water Science and Engineering, 2008 Coarse aggregates are the major infrastructure materials of concrete-faced rock-fill dams and are consolidated to bear upper and lateral loads. With the increase of dam height, high confining pressure and complex stress states complicate the shear ...
Liu Hanlong, Deng An, Shen Yang
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Lines of principal curvature for mappings with Whitney umbrella singularities
Tohoku Mathematical Journal, 1986 A mapping of a 2-manifold \(\alpha\) : \(M\to {\mathbb{R}}^ 3\) has a Whitney umbrella singularity at a point p if there is a chart for which \(\alpha_ v(0)=0\) and \(\alpha_ u(0)\), \(\alpha_{uu}(0)\), \(\alpha_{vv}(0)\) span \({\mathbb{R}}^ 3\). The authors show that a Whitney umbrella has a single tangent to all curvature lines.
Gutiérrez, Carlos, Sotomayor, Jorge
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Efficient vanishing point detection method in complex urban road environments
IET Computer Vision, 2015 Detecting the vanishing point in a road image is important for robot navigation, intelligent transportation and other fields. This study proposes a new vanishing point detection method that uses the vertical information in complex urban road and street ...
Weili Ding, Yong Li
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On Ribaucour transformations and applications to linear Weingarten surfaces
Anais da Academia Brasileira de Ciências, 2002 We present a revised definition of a Ribaucour transformation for submanifolds of space forms, with flat normal bundle, motivated by the classical definition and by more recent extensions.
KETI TENENBLAT
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