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<XML><RECORDS>
<RECORD>
	<REFERENCE_TYPE>0</REFERENCE_TYPE>
	<AUTHORS>
		<AUTHOR>María Luisa Bonet</AUTHOR>
		<AUTHOR>Jordi Levy</AUTHOR>
		<AUTHOR>Felip Manyà</AUTHOR>
	</AUTHORS>
	<YEAR>2007</YEAR>
	<TITLE>Resolution for Max-SAT</TITLE>
	<SECONDARY_TITLE>Artificial Intelligence</SECONDARY_TITLE>
	<VOLUME>171</VOLUME>
	<PAGES>606-618</PAGES>
	<KEYWORDS>
		<KEYWORD>Max-SAT</KEYWORD>
	</KEYWORDS>
	<ABSTRACT>Max-SAT is the problem of finding an assignment minimizing the number of unsatisfied clauses of a given CNF formula. We propose a resolution-like calculus for Max-SAT and prove its soundness and completeness. We also prove the completeness of some refinements of this calculus. From the completeness proof we derive an exact algorithm for Max-SAT and a time upper bound. We also give a weighted Max-SAT resolution-like rule, and show how to adapt the soundness and completeness proofs of the Max-SAT rule to the weighted Max-SAT one. Finally we give several particular Max-SAT problems that require an exponential number of steps of our Max-SAT rule to obtain the minimal number of unsatisfied clauses of the combinatorial principle. These results are based on the corresponding Resolution lower bounds for those particular problems.</ABSTRACT>
</RECORD>
</RECORDS></XML>