Results 41 to 50 of about 118 (114)

SPARSE APPROXIMATION AND RECOVERY BY GREEDY ALGORITHMS IN BANACH SPACES

Forum of Mathematics, Sigma, 2014
We study sparse approximation by greedy algorithms. We prove the Lebesgue-type inequalities for the weak Chebyshev greedy algorithm (WCGA), a generalization of the weak orthogonal matching pursuit to the case of a Banach space.
V. N. TEMLYAKOV
doaj   +1 more source

On Various Types of Uniform Rotundities

Annales Mathematicae Silesianae
In this study, we conduct a literature review on normed linear spaces whose strengths are between rotundity and uniform rotundity. In this discourse, we also explore inter-relationships and juxtapositions between the subjects under consideration.
Narang Tulsi Dass, Chandok Sumit, Gupta Sahil   +2 more
doaj   +1 more source

The diameter of the Birkhoff polytope

Special Matrices
The geometry of the compact convex set of all n×nn\times n doubly stochastic matrices, a structure frequently referred to as the Birkhoff polytope, has been an active subject of research as of late.
Bouthat Ludovick, Mashreghi Javad, Morneau-Guérin Frédéric   +2 more
doaj   +1 more source

Convexity around the Unit of a Banach Algebra [PDF]

, 2008
2000 Mathematics Subject Classification: Primary: 46B20. Secondary: 46H99, 47A12.We estimate the (midpoint) modulus of convexity at the unit 1 of a Banach algebra A showing that inf {max±||1 ± x|| − 1 : x ∈ A, ||x||=ε} ≥ (π/4e)ε²+o(ε²) as ε → 0. We also
Vishnyakova, Anna, Martín, Miguel, Kadets, Vladimir, Katkova, Olga   +3 more
core  

Some geometric properties of the metric space V[λ,p]

, 2013
In this study, we consider the space [InlineEquation not available: see fulltext.] with an invariant metric. Then, we examine some geometric properties of the linear metric space [InlineEquation not available: see fulltext.] such as property ...
Mikail Et, Muhammed Çinar, Murat Karakaş, Çinar, M., Karakaş, M., Et, Mikail   +5 more
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ON $\omega$-INDEPENDENCE AND THE KUNEN–SHELAH PROPERTY

, 2002
We prove that spaces with an uncountable $\omega$-independent family fail the Kunen–Shelah property. Actually, if $\{x_i\}_{i\in I}$ is an uncountable $\omega$-independent family, there exists an uncountable subset $J\subset I$ such that $x_j\notin ...
Moreno, José Pedro, Jiménez Sevilla, María Del Mar, M. Jiménez-Sevilla, J. P. Moreno, Suárez Granero, Antonio, A. S. Granero   +5 more
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Uniform G-Convexity for Vector-Valued Lp Spaces [PDF]

, 2009
2000 Mathematics Subject Classification: 46B20.Uniform G-convexity of Banach spaces is a recently introduced natural generalization of uniform convexity and of complex uniform convexity.
Kadets, Vladimir, Boyko, Nataliia
core  

Noncyclic Meir-Keeler contractions and best proximity pair theorems

Demonstratio Mathematica, 2018
In this article, we consider the class of noncyclic Meir-Keeler contractions and study the existence and convergence of best proximity pairs for such mappings in the setting of complete CAT(0) spaces.
Gabeleh Moosa, Markin Jack
doaj   +1 more source

On a universal inequality for approximate phase isometries

39B05; 46B04; 46B20; Banach space; phase isometry; ε-phase ...
Dai, Duanxu, Zheng, Bentuo, Sun, Longfa, Que, Haixin   +3 more
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Reduction of finite exhausters

Minkowski–Rådström–Hörmander spaces, Exhausters, Pairs of closed bounded convex sets, 46B20, 52A05, 54B20,
Ryszard Urbański, Diethard Pallaschke, Jerzy Grzybowski   +2 more
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