Recently Bansal and Sviridenko (Proc. of the 15th SODA'04, 189-196)
proved that for
2-dimensional Orthogonal Rectangle
Bin Packing without rotations allowed there is no asymptotic PTAS, unless P=NP. We show that similar
approximation hardness results hold for several rectangle packing and covering problems even if rotations by ninety
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We study small degree graph problems such as Maximum Independent Set
and Minimum Node Cover and improve approximation lower bounds for
them and for a number of related problems, like Max-B-Set Packing,
Min-B-Set Cover, Max-Matching in B-uniform 2-regular hypergraphs.
For example, we prove NP-hardness factor of 95/94
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The paper contributes to the systematic study (started by Berman and
Karpinski) of explicit approximability lower bounds for small occurrence optimization
problems. We present parametrized reductions for some packing and
covering problems, including 3-Dimensional Matching, and prove the best
known inapproximability results even for highly restricted versions of ...
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