Results 21 to 30 of about 727,489 (238)

Projections of Tropical Fermat-Weber Points

Mathematics, 2021
This paper is motivated by the difference between the classical principal component analysis (PCA) in a Euclidean space and the tropical PCA in a tropical projective torus as follows.
Weiyi Ding, Xiaoxian Tang
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The Representations and Continuity of the Metric Projections on Two Classes of Half-Spaces in Banach Spaces

Abstract and Applied Analysis, 2014
We show a necessary and sufficient condition for the existence of metric projection on a class of half-space Kx0*,c={x∈X:x*(x)≤c} in Banach space. Two representations of metric projections PKx0*,c and PKx0,c are given, respectively, where Kx0,c stands ...
Zihou Zhang, Chunyan Liu
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Object-Based Geometric Distortion Metric for Viewport Rendering of 360° Images

IEEE Access, 2022
To visualize omnidirectional (or 360°) visual content, a sphere to plane projection is employed, that maps pixels from the observed sphere region to a 2D image, called as viewport. However, this projection introduces geometrical distortions on the
Falah Jabar, Joao Ascenso, Maria Paula Queluz   +2 more
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Layered Projection-Based Quality Assessment of 3D Point Clouds

IEEE Access, 2021
Point clouds are subject to various distortions during point cloud processing missions, any of which may lead to quality degradation. Consequently, predicting point cloud quality has attracted a lot of attention. In this paper, a layered projection-based
Tianxin Chen, Chunyi Long, Honglei Su, Lijun Chen, Jieru Chi, Zhenkuan Pan, Huan Yang, Yuxin Liu   +7 more
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Multi-Feature 360 Video Quality Estimation

IEEE Open Journal of Circuits and Systems, 2021
We propose a new method for the visual quality assessment of 360-degree (omnidirectional) videos. The proposed method is based on computing multiple spatio-temporal objective quality features on viewports extracted from 360-degree videos.
Roberto G. de A. Azevedo, Neil Birkbeck, Ivan Janatra, Balu Adsumilli, Pascal Frossard   +4 more
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Directional Differentiability of the Generalized Metric Projection in Banach Spaces [PDF]

, 2023
Let X be a real uniformly convex and uniformly smooth Banach space and C a nonempty closed and convex subset of X. In this paper, we consider the generalized metric projection operator from X to C, which was introduced by Alber in 1996.
Li, Jinlu
core  

On metrics projectively and holomorphically projectively equivalent to metrics of parabolic Riemannian and Kähler manifolds

Filomat, 2023
We prove a number of nonexistence theorems for metrics projectively and holomorphically projectively equivalent to parabolic metrics and metrics of finite volume of complete Riemannian and K?hler manifolds, respectively.
Mikeš, Josef, Stepanov, Sergey, Tsyganok, Irina   +2 more
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The metric projection for free knot splines [PDF]

, 1990
Only few results are known on continuity properties of the set-valued metric projection in nonlinear uniform approximation. In this paper we investigate this mapping in the case of best uniform approximation by splines of degree m with k free knots.
Nürnberger, Günther
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Selections associated to the metric projection

Journal of Numerical Analysis and Approximation Theory, 1995
Not available.
Ştefan Cobzaş, C. Mustăţa
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Extensions of best approximation and coincidence theorems

International Journal of Mathematics and Mathematical Sciences, 1997
Let X be a Hausdorff compact space, E a topological vector space on which E* separates points, F:X→2E an upper semicontinuous multifunction with compact acyclic values, and g:X→E a continuous function such that g(X) is convex and g−1(y) is acyclic for ...
Sehie Park
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