In view of possible applications to abstract convex programs, Barker, Laidacker, and Poole have made an initial study of p-exposed cones and o.p.-exposed cones by restricting their attention to closed, pointed cones. A study of these cones is continued in this paper. Sufficient conditions for a face of a proper cone to be a p-exposed or an o.p.-exposed face are established. Characterizations of o.p.-exposed cones among polyhedral cones are also obtained. The relation between exposedness and p-exposedness of faces of a general cone is examined. As one consequence, a question posed by Iochum is answered in the finite dimensional case; that is, there is no finite-dimensional semiregular self-dual cones which are not regular. Also, a conjecture posed by Barker and Thompson on p-exposed faces of P(n), that the cone of all real polynomials of degree⩽n which are nonnegative on the closed interval [0,1], is settled.
Relation:
Linear Algebra and Its Applications 139, pp.225-252
