Results 11 to 20 of about 267,369 (299)
Nonpositivity: Curvature vs. curvature operator [PDF]
Proceedings of the American Mathematical Society, 2004 It is shown that there exist closed Riemannian manifolds M M all of whose sectional curvatures are negative, but M M does not admit any metric with nonpositive curvature operator.
Aravinda, C. S., Farrell, F. T.
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Mean Curvature in the Light of Scalar Curvature [PDF]
Annales de l'Institut Fourier, 2020 We formulate several conjectures on mean convex domains in the Euclidean spaces, as well as in more general spaces with lower bounds on their scalar curvatures, and prove a few theorems motivating these ...
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Blindness to Curvature and Blindness to Illusory Curvature [PDF]
i-Perception, 2018 We compare two versions of two known phenomena, the Curvature blindness and the Kite mesh illusions, to highlight how similar manipulations lead to blindness to curvature and blindness to illusory curvature, respectively. The critical factor is a change in luminance polarity; this factor interferes with the computation of curvature along the contour ...
Bertamini, Marco, Kitaoka, Akiyoshi
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Scalar Curvature and Q-Curvature of Random Metrics [PDF]
The Journal of Geometric Analysis, 2010 We study Gauss curvature for random Riemannian metrics on a compact surface, lying in a fixed conformal class; our questions are motivated by comparison geometry. Next, analogous questions are considered for the scalar curvature in dimension $n>2$, and for the $Q$-curvature of random Riemannian metrics.
Canzani, Yaiza +2 more
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Exploring Benefits of Using Blending Splines as Transition Curves
Applied Sciences, 2020 Track geometry is a fundamental subject in railway construction. With the demand for increased capacity in terms of load and speed, the need for suitable transitions between consecutive track sections is highly relevant.
Tanita Fossli Brustad, Rune Dalmo
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IEEE Access, 2022 Aiming at the problems in the best basis selection, this paper presents a novel criterion based on the statistical measurement of the curvature wavelet coefficient to dynamically select the single best basis of the quad-tree wavelet packet transformation.
Regina Lionnie +3 more
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International Journal of Modern Physics D, 2002 The issues of quintessence and cosmic acceleration can be discussed in the framework of higher order theories of gravity. We can define effective pressure and energy density directly connected to the Ricci scalar of curvature of a generic fourth order theory and then ask for the conditions to get an accelerated expansion.
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Curvature-Based Machine Vision Method for Measuring the Dimension of Ball Screws
IEEE Access, 2023 As a linear actuator, accurate dimension measurement is crucial to the transmission reliability and interchangeability of ball screws. However, most of the current approaches are ineligible for rapid ball screw in-situ inspections due to the installation
Yijia Chen +5 more
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Annals of the Academy of Romanian Scientists Series on Mathematics and Its Application, 2023 This short paper is devoted to a strange looking question: is it possible to deduce the shape of a smooth convex set by measuring at each point the distance of the horizon standing at a fixed height h? The question is surprisingly difficult and we only have partial results.
Alain Haraux +2 more
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Earth's curvature and visibility between two points [PDF]
Vojnotehnički Glasnik, 2012 In this study, the Earth's curvature is analyzed from numerous aspects as well as the visibility between two points on the Earth's surface. It also describes the way and the size of the Earth's part which can be approximated in the plane depending on the
Mirko A. Borisov, Radoje D. Banković
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