Gaps between optimal values of some packing and scheduling problems
نویسندگان
چکیده
We consider three connected resource-constrained optimization problems: 1D bin packing (BPP), resource-constrained project scheduling (PSP), and 2D strip packing without rotation (SPP). In the context of SPP, BPP is also known as the 1D bar relaxation and PSP as the 1D contiguous relaxation. It is easy to see that SPP can be relaxed in two different ways down to a PSP: horizontal and vertical scheduling relaxation. In turn, PSP itself can be relaxed down to BPP, again in two different ways, horizontal and vertical 1D bar relaxation. We investigate the quality of these relaxations.
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