Results 41 to 50 of about 1,388,848 (321)
Best approximation in Chebyshev subspaces of L(l_{1}^{n},l_{1}^{n}) [PDF]
Opuscula Mathematica, 2009 Chebyshev subspaces of \(\mathcal{L}(l_1^n,l_1^n)\) are studied. A construction of a \(k\)-dimensional Chebyshev (not interpolating) subspace is given.
Joanna Kowynia
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On Best Simultaneous Approximation
Journal of Approximation Theory, 1997 Let \(X\) be a compact Hausdorff space, \(Y\) be a normed linear space, \(C(X, Y)\) be the vector space of continuous functions from \(X\) to \(Y\) and \(S\) be a subspace of \(C(X, Y).\) Suppose that \(C(X, Y)\) is normed with a given norm \(\| \cdot\| _A\) and that \(U\) is the unit ball of \((\mathbb R^n, \| \cdot\| _B).
Li, Chong, Watson, G.A
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, 2019 The problem of finding a $k \times k$ submatrix of maximum volume of a matrix $A$ is of interest in a variety of applications. For example, it yields a quasi-best low-rank approximation constructed from the rows and columns of $A$.
Cortinovis, Alice +2 more
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Pointwise best approximation results for Galerkin finite element solutions of parabolic problems [PDF]
, 2016 In this paper we establish a best approximation property of fully discrete Galerkin finite element solutions of second order parabolic problems on convex polygonal and polyhedral domains in the $L^\infty$ norm.
Leykekhman, Dmitriy, Vexler, Boris
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Best approximation in b-modular spaces
مجلة بغداد للعلومIn this paper, some basic notions and facts in the b-modular space similar to those in the modular spaces as a type of generalization are given. For example, concepts of convergence, best approximate, uniformly convexity etc.
Hiba Adel Jabbar +2 more
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A topological approach to Best Approximation Theory
Applied General Topology, 2004 The main goal of this paper is to put some light in several arguments that have been used through the time in many contexts of Best Approximation Theory to produce proximinality results. In all these works, the main idea was to prove that the sets we are
Samuel G. Moreno +3 more
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BEST APPROXIMATION AND BEST SIMULTANEOUS APPROXIMATION IN ULTRAMETRIC SPACES
Demonstratio Mathematica, 1996 A metric space \(X\) is ultrametric if the metric \(d\) satisfies the strong triangle inequality \(d(x,y)\leq\max\{d(x,z),d(z,y)\}\) for every \(x,y,z\in X\). The author considers various best approximation problems in an ultrametric setting and their relationship with the proximinal property.
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Results of the Childhood Cancer and Leukaemia Group's United Kingdom Relapsed Wilms Tumour Trial
Pediatric Blood &Cancer, EarlyView.ABSTRACT Background The United Kingdom relapsed Wilms tumour (UKW‐R) trial aimed to improve the historically low survival rates after relapse of Wilms tumour (WT) through a prospective national risk‐stratified protocol. The trial also evaluated efficacy and toxicity of high‐dose melphalan.
Sucheta J. Vaidya +10 more
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Journal of Approximation Theory, 1984 This paper studies best \(L_ 1\)-approximation of continuous functions defined on an interval [a,b]. First a condition is established ensuring uniqueness of best \(L_ 1\)-approximation. This condition can be considered as a generalized Haar condition.
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Journal of Approximation Theory, 1978 AbstractIn 1934, Walsh noted that the Taylor polynomial of degree n can be obtained by taking the limit as ϵ → 0+ of the net of nth degree polynomials which best approximate f in the closed discs ¦ z ¦ ⩽ ϵ. Later, this result was generalized to rational approximation. In a recent paper, Shisha and the first two authors generalized this idea to the idea
Chui, C.K, Smith, P.W, Ward, J.D
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