Results 11 to 20 of about 464,650 (293)
A Scale Invariant Surface Curvature Estimator
, 2006 In this paper we introduce a new scale invariant curvature measure, similarity curvature. We define a similarity curvature space which consists of the set of all possible similarity curvature values. An estimator for the similarity curvature of digital surface points is developed.
John Rugis, Reinhard Klette
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On the curvature of invariant Kropina metrics
, 2011 In the present article we compute the flag curvature of a special type of invariant Kropina metrics on homogeneous spaces.
Communicated Moghaddam +2 more
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2.5D Multi-View Gait Recognition Based on Point Cloud Registration [PDF]
Sensors, 2014 This paper presents a method for modeling a 2.5-dimensional (2.5D) human body and extracting the gait features for identifying the human subject.
Jin Tang +3 more
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The constant curvature property of the Wu invariant metric [PDF]
Pacific Journal of Mathematics, 2003 The object of the article under review is the hermitian metric introduced by \textit{H. H.Wu} [Several complex variables, Proc. Mittag-Leffler Inst., Stockholm/Swed. 1987-88, Math. Notes 38, 640--682 (1993; Zbl 0773.32017)]. In their main results the authors prove curvature properties of this metric, namely: Theorem 1: Let \(\Omega\) be a domain ...
Cheung, CK, Kim, KT
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Curvature Invariants for the Accelerating Natário Warp Drive [PDF]
Particles, 2020 A process for using curvature invariants is applied to evaluate the accelerating Natário warp drive. Curvature invariants are independent of coordinate bases and plotting the invariants is free of coordinate mapping distortions.
Brandon Mattingly +11 more
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Projective Curvature and Integral Invariants [PDF]
Acta Applicandae Mathematica, 2002 It is known, that the projective group and its three subgroups namely the Euclidean group \(E(2)\), special affine group \(SA(2)\) and the full affine group \(A(2)\) play an important role in computer vision. The fundamental invariant of the projective group is the projective curvature which characterises curves under a projective transformation.
Hann, C.E., Hickman, M.S.
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Curvature operators and scalar curvature invariants [PDF]
Classical and Quantum Gravity, 2010 We continue the study of the question of when a pseudo-Riemannain manifold can be locally characterised by its scalar polynomial curvature invariants (constructed from the Riemann tensor and its covariant derivatives). We make further use of alignment theory and the bivector form of the Weyl operator in higher dimensions, and introduce the important ...
Hervik, Sigbjørn, Coley, Alan
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Curvature invariants in type- N spacetimes [PDF]
Classical and Quantum Gravity, 1998 Scalar curvature invariants are studied in type N solutions of vacuum Einstein's equations with in general non-vanishing cosmological constant Lambda. Zero-order invariants which include only the metric and Weyl (Riemann) tensor either vanish, or are constants depending on Lambda. Even all higher-order invariants containing covariant derivatives of the
Bicak, J., Pravda, V.
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CURVATURE INVARIANTS IN ALGEBRAICALLY SPECIAL SPACETIMES [PDF]
The Ninth Marcel Grossmann Meeting, 2002 It is well known that all curvature invariants of the order zero vanish for type-III and type-N vacuum spacetimes. We briefly summarize properties of higher order curvature invariants for these spacetimes.
Pravda, V., Bicak, J.
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Universality and Constant Scalar Curvature Invariants [PDF]
ISRN Geometry, 2011 A classical solution is called universal if the quantum correction is a multiple of the metric. Therefore, universal solutions play an important role in the quantum theory. We show that in a spacetime which is universal all scalar curvature invariants are constant (i.e., the spacetime is CSI).
Coley, A. A., Hervik, S.
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