Lower Semicontinuity Concepts, Continuous Selections, and Set Valued Metric Projections
نویسندگان
چکیده
A number of semicontinuity concepts and the relations between them are discussed. Characterizations are given for when the (set-valued) metric projection P M onto a proximinal subspace M of a normed linear space X is approximate lower semicontinuous or 2-lower semicontinuous. A geometric characterization is given of those normed linear spaces X such that the metric projection onto every one-dimensional subspace has a continuous C 0 (T) and L 1 (m) that have this property are determined.
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ورودعنوان ژورنال:
- Journal of Approximation Theory
دوره 115 شماره
صفحات -
تاریخ انتشار 2002