Delta-semidefinite and Delta-convex Quadratic Forms in Banach Spaces
نویسندگان
چکیده
منابع مشابه
Nearest Points and Delta Convex Functions in Banach Spaces
Given a closed set C in a Banach space (X, ‖ · ‖), a point x ∈ X is said to have a nearest point in C if there exists z ∈ C such that dC(x) = ‖x − z‖, where dC is the distance of x from C. We shortly survey the problem of studying the size of the set of points in X which have nearest points in C. We then turn to the topic of delta-convex functions and indicate how it is related to finding neare...
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ژورنال
عنوان ژورنال: Positivity
سال: 2008
ISSN: 1385-1292,1572-9281
DOI: 10.1007/s11117-007-2106-6