Abstract

The maximum satisfiability problem (MAX-SAT) refers to the task of finding a variable assignment that satisfies the maximum number of clauses (or the sum of weight of satisfied clauses) in a Boolean Formula. Most local search algorithms including tabu search rely on the 1-flip neighbourhood structure. In this work, we introduce a tabu search algorithm that makes use of the multilevel paradigm for solving MAX-SAT problems. The multilevel paradigm refers to the process of dividing large and difficult problems into smaller ones, which are hopefully much easier to solve, and then work backward towards the solution of the original problem, using a solution from a previous level as a starting solution at the next level. This process aims at looking at the search as a multilevel process operating in a coarse-to-fine strategy evolving from k-flip neighbourhood to 1-flip neighbourhood-based structure. Experimental results comparing the multilevel tabu search against its single level variant are presented.

Highlights

  • IntroductionComplete [1] plays a central role problem in many applications in the fields of VLSI Computer-Aided design, Computing Theory, and Artificial Intelligence

  • The satisfiability problem which is known to be NP-complete [1] plays a central role problem in many applications in the fields of VLSI Computer-Aided design, Computing Theory, and Artificial Intelligence

  • We introduce a tabu search algorithm that makes use of the multilevel paradigm for solving maximum satisfiability problem (MAX-SAT) problems

Read more

Summary

Introduction

Complete [1] plays a central role problem in many applications in the fields of VLSI Computer-Aided design, Computing Theory, and Artificial Intelligence. Efficient methods that can solve large and hard instances of MAX-SAT are eagerly sought Due to their combinatorial explosion nature, large and complex MAX-SAT problems are hard to solve using systematic algorithms based on branch and bound techniques [2]. This work is motivated by the recent results presented in [5] where the multilevel paradigm was capable of improving the asymptotic convergence of memetic algorithms dramatically on large industrial instances. To this end, the focus is restricted to formulas in which all the weights are equal to 1 i.e. unweighted MAX-SAT) using a offset of industrial problem instances.

Related Work
Tabu Search
Multilevel Tabu Search
Reduction Phase
Initial Solution
Projection Phase
Improvement Phase
Experimental Results
Conclusion

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.