Accession Number:

ADA123984

Title:

Lower Bounds for ON-Line Two-Dimensional Packing Algorithms.

Descriptive Note:

Technical rept.,

Corporate Author:

ILLINOIS UNIV AT URBANA APPLIED COMPUTATION THEORY GROUP

Report Date:

1980-07-01

Pagination or Media Count:

26.0

Abstract:

Many problems, such as cutting stock problems and the scheduling of tasks with a shared resource, can be viewed as two-dimensional bin packing problems. Using the two-dimensional packing model of Baker, Coffman, and Rivest, a finite list L of rectangles is to be packed into a rectangular bin of finite width but infinite height, so as to minimize the total height used. An algorithm which packs the list in the order given without looking ahead or moving pieces already packed is called an on-line algorithm. Since the problem of finding an optimal packing is NP-hard, previous work has been directed at finding approximation algorithms. Most of the approximation algorithms which have been studied are on-line except that they require the list to have been previously sorted by height or width. This paper examines lower bounds for the worst-case performance of on-line algorithms for both non-preordered lists and for lists preordered by increasing or decreasing height of width. Author

Subject Categories:

  • Theoretical Mathematics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE