Results 11 to 20 of about 151 (41)
Positive operators and approximation in function spaces on completely regular spaces
International Journal of Mathematics and Mathematical Sciences, Volume 2003, Issue 61, Page 3841-3871, 2003., 2003 We discuss the approximation properties of nets of positive linear operators acting on function spaces defined on Hausdorff completely regular spaces. A particular attention is devoted to positive operators which are defined in terms of integrals with respect to a given family of Borel measures.
Francesco Altomare, Sabrina Diomede
wiley +1 more source
FARTHEST POINTS IN HILBERT OPERATOR SPACES WITH APPLICATIONS
, 2015 The purpose of this paper is to Provide conditions for the existence of farthest points of closed and bounded subsets of Hilbert operator spaces. This will done by applying the concept of numerical range. We give, inter alia, some results to characterize
M. Iranmanesh, F. Soleimany
semanticscholar +1 more source
A General Approximation Approach for the Simultaneous Treatment of Integral and Discrete Operators
Advanced Nonlinear Studies, 2018 In this paper, we give a unitary approach for the simultaneous study of the convergence of discrete and integral operators described by means of a family of linear continuous functionals acting on functions defined on locally compact Hausdorff ...
Vinti Gianluca, Zampogni Luca
doaj +1 more source
Best approximation by diagonal compact operators [PDF]
, 2013 We study the existence and characterization properties of compact Hermitian operators C on a separable Hilbert space H such that ||C|| is less or equal than || C + D ||, for all D in D(K(H)). This property is equivalent to || C || = min{||C+D||: D in D(K(
Bottazzi, Tamara, Varela, Alejandro
core +3 more sources
Weighted projections into closed subspaces [PDF]
, 2013 In this paper we study $A$-projections, i.e. operators of a Hilbert space $\HH$ which act as projections when a seminorm is considered in $\HH$. $A$-projections were introduced by Mitra and Rao \cite{[MitRao74]} for finite dimensional spaces.
Corach, Gustavo +2 more
core +3 more sources
Approximation results for a general class of Kantorovich type operators [PDF]
, 2014 We introduce and study a family of integral operators in the Kantorovich sense for functions acting on locally compact topological groups. We obtain convergence results for the above operators with respect to the pointwise and uniform convergence and in ...
Vinti, Gianluca, Zampogni, Luca
core +1 more source
Matrix formulation for infinite-rank operators
, 2012 Every finite-rank operator on a linear space X is the composition of an operator from X to a finite dimensional Euclidean space and of an operator from that Euclidean space to X .
B. V. Limaye
semanticscholar +1 more source
A philosophy for the modelling of realistic nonlinear systems [PDF]
, 2003 First published in Proceedings of the American Mathematical Society in volume 132, number 2, by the American Mathematical Society Copyright © 2003 American Mathematical SocietyA nonlinear dynamical system is modelled as a nonlinear mapping from a set of ...
Howlett, P., Pearce, C., Torokhti, A.
core +1 more source
Strongly convergent approximations to fixed points of total asymptotically nonexpansive mappings [PDF]
, 2008 In this work we prove a new strong convergence result of the regularized successive approximation method given by yn+1 = qnz0 + (1 − qn)T n yn, n = 1, 2, ..., where limn→∞ qn = 0 and X∞ n=1 qn = ∞, for T a total asymptotically nonexpansive ...
Alber, Yakov +2 more
core +1 more source
New modification of the Post Widder operators preserving exponential functions
Arab Journal of Basic and Applied SciencesThe current article deals with a modification of the Post-Widder operators which reproduce the exponential functions both [Formula: see text] and [Formula: see text] for [Formula: see text] The central moments, uniform convergence of the operators and ...
Melek Sofyalıoğlu Aksoy
doaj +1 more source