Discrete Lagrangian-Based Search for Solving MAX-SAT Problems
نویسندگان
چکیده
Weighted maximum satissability problems (MAX-SAT) are diicult to solve due to the large number of local minima in their search space. In this paper we propose a new discrete Lagrangian based search method (DLM) for solving these problems. Instead of restarting from a new point when the search reaches a local minimum, the Lagrange multipliers in DLM provide a force to lead the search out of the local minimum and move it in a direction provided by the multipliers. Since DLM has very few parameters to be tuned, it can be made de-terministic and the results, reproducible. We compare DLM with GRASP in solving a large set of test problems, and show that it nds better solutions and is substantially faster. DLM has a solid theoretical foundation that can be used as a systematic approach for solving general discrete optimization problems.
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