Off-campus UMass Amherst users: To download dissertations, please use the following link to log into our proxy server with your UMass Amherst user name and password.
Non-UMass Amherst users, please click the view more button below to purchase a copy of this dissertation from Proquest.
(Some titles may also be available free of charge in our Open Access Dissertation Collection, so please check there first.)
Sacrificing: An augmentation of local search
Abstract
The discrete optimization technique called local search yields impressive results on many important combinatorial optimization problems. Its tendency to return solutions that are sub-optimal, however, remains a serious limitation of the approach. In this dissertation we propose and investigate a general technique that seeks to overcome this difficulty while maintaining the speed that makes local search an attractive approach. We focus on constrained problems which have an induced non-uniform neighborhood structure, and we examine three such problems experimentally. Our example set is: (1) a variant of Stock Cutting; (2) a precedence constrained routing problem; and (3) a weighted version of the latter. Using our techniques we have been able to improve significantly the quality of solutions found in each of these domains over that found by the traditional local search algorithm, with only modest increases in running time. Our technique is independent of problem domain and, therefore, is applicable to a wide variety of problems.
Subject Area
Computer science|Operations research
Recommended Citation
Healy, Patrick, "Sacrificing: An augmentation of local search" (1991). Doctoral Dissertations Available from Proquest. AAI9132864.
https://scholarworks.umass.edu/dissertations/AAI9132864