Results 11 to 20 of about 64,214 (233)
Polynomial Approximation on Unbounded Subsets, Markov Moment Problem and Other Applications [PDF]
Mathematics, 2020 This paper starts by recalling the author’s results on polynomial approximation over a Cartesian product A of closed unbounded intervals and its applications to solving Markov moment problems.
Octav Olteanu
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Fixed point theorems for asymptotically contractive mappings [PDF]
Le Matematiche, 2003 In this short paper, we prove fixed point theorems for nonexpansive mappings whose domains are unbounded subsets of Banach spaces. These theorems are generalizations of Penot's result in [4].
Tomonari Suzuki
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Polynomial Approximation on Unbounded Subsets and the Markov Moment Problem
International Journal of Analysis and Applications, 2013 We start this review paper by recalling some known and relatively recent results in polynomial approximation on unbounded subsets. These results allow approximation of nonnegative continuous functions with compact support contained in the first quadrant ...
Octav Olteanu
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Semilinear elliptic problems on unbounded subsets of the Heisenberg group
Electronic Journal of Differential Equations, 2001 In this paper we discuss the applications of an abstract version of concentration compactness to minimax problems. In particular, we prove the existence of solutions to semilinear elliptic problems on unbounded subsets of the Heisenberg group.
K. Tintarev
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On the VC-dimension of half-spaces with respect to convex sets [PDF]
Discrete Mathematics & Theoretical Computer Science, 2021 A family S of convex sets in the plane defines a hypergraph H = (S, E) as follows. Every subfamily S' of S defines a hyperedge of H if and only if there exists a halfspace h that fully contains S' , and no other set of S is fully contained in h.
Nicolas Grelier +3 more
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On Undecidability of Finite Subsets Theory for Torsion Abelian Groups
Mathematics, 2022 Let M be a commutative cancellative monoid with an element of infinite order. The binary operation can be extended to all finite subsets of M by the pointwise definition. So, we can consider the theory of finite subsets of M.
Sergey Mikhailovich Dudakov
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On the Moment Problem and Related Problems
Mathematics, 2021 Firstly, we recall the classical moment problem and some basic results related to it. By its formulation, this is an inverse problem: being given a sequence (yj)j∈ℕn of real numbers and a closed subset F⊆ℝn, n∈{1,2,…}, find a positive regular Borel ...
Octav Olteanu
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Mathematics, 2022 As is well-known, unlike the one-dimensional case, there exist nonnegative polynomials in several real variables that are not sums of squares. First, we briefly review a method of approximating any real-valued nonnegative continuous compactly supported ...
Octav Olteanu
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Closeness and linkness in balleans
Математичні Студії, 2020 A set $X$ endowed with a coarse structure is called ballean or coarse space. For a ballean $(X, \mathcal{E})$, we say that two subsets $A$, $B$ of $X$ are close (linked) if there exists an entourage $E\in \mathcal{E}$ such that $A\subseteq E [B]$, $B ...
I.V. Protasov, K. Protasova
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Representations of bornologies
Applied General Topology, 2022 Bornologies abstract the properties of bounded sets of a metric space. But there are unbounded bornologies on a metric space like $\mathcal{P}(\RR)$ with the Euclidean metric.
Homeira Pajoohesh
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