Piercing disks with tame arcs.
نویسندگان
چکیده
منابع مشابه
Tame Arcs on Disks
It is the goal of this note to show that each disk in E3 contains a tame arc which intersects the boundary of D. In [l ] Bing shows that each disk in E3 contains many tame arcs. The reason that the arguments given in [l ] do not show that each disk contains a tame arc intersecting the boundary is that a disk in E3 need not lie on a closed surface in E3 [7]. This difficulty can be overcome using...
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1. Introduction. R. H. Bing showed that an upper semicontinuous decomposition of £3 into points and tame arcs did not necessarily produce a decomposition space topologically equivalent to E3 [1J. M. L. Curtis and R. L. Wilder showed [2] that the decomposition space of Bing was a homotopy manifold, thus negatively answering a question proposed by Griffiths [3J. R. Rosen recently announced [4] a ...
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In this note, we shall consider constant factor approximation algorithms for a variation of the discrete piercing set problem for unit disks. Here a set of points P is given; the objective is to choose minimum number of points in P to pierce all the disks of unit radius centered at the points in P . We first propose a very simple algorithm that produces a 14-factor approximation result in O(n l...
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ژورنال
عنوان ژورنال: Michigan Mathematical Journal
سال: 1974
ISSN: 0026-2285
DOI: 10.1307/mmj/1029001151