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	<front>
		<journal-meta>
			<journal-id journal-id-type="publisher-id">INFORMATICA</journal-id>
			<journal-title-group>
				<journal-title>Informatica</journal-title>
			</journal-title-group>
			<issn pub-type="epub">0868-4952</issn>
			<issn pub-type="ppub">0868-4952</issn>
			<publisher>
				<publisher-name>VU</publisher-name>
			</publisher>
		</journal-meta>
		<article-meta>
			<article-id pub-id-type="publisher-id">INFO1098</article-id>
			<article-id pub-id-type="doi">10.15388/Informatica.2016.93</article-id>
			<article-categories>
				<subj-group subj-group-type="heading">
					<subject>Research Article</subject>
				</subj-group>
			</article-categories>
			<title-group>
				<article-title>Dynamic-Programming-Based Inequalities for the Unbounded Integer Knapsack Problem</article-title>
			</title-group>
			<contrib-group>
				<contrib contrib-type="Author">
					<name>
						<surname>He</surname>
						<given-names>Xueqi</given-names>
					</name>
					<email xlink:href="mailto:he0429@ufl.edu">he0429@ufl.edu</email>
					<xref ref-type="aff" rid="j_INFORMATICA_aff_000"/>
					<xref ref-type="corresp" rid="cor1">*</xref>
				</contrib>
				<contrib contrib-type="Author">
					<name>
						<surname>Hartman</surname>
						<given-names>Joseph C.</given-names>
					</name>
					<xref ref-type="aff" rid="j_INFORMATICA_aff_001"/>
				</contrib>
				<contrib contrib-type="Author">
					<name>
						<surname>Pardalos</surname>
						<given-names>Panos M.</given-names>
					</name>
					<xref ref-type="aff" rid="j_INFORMATICA_aff_000"/>
				</contrib>
				<aff id="j_INFORMATICA_aff_000">Industrial and Systems Engineering, University of Florida, Gainesville, FL 32611, USA
				</aff>
				<aff id="j_INFORMATICA_aff_001">Francis College of Engineering, University of Massachusetts Lowell, Lowell, MA 01854, USA</aff>
			</contrib-group>
			<author-notes>
				<corresp id="cor1">
					<label>*</label>Corresponding author.</corresp>
			</author-notes>
			<pub-date pub-type="epub">
				<day>01</day>
				<month>01</month>
				<year>2016</year>
			</pub-date>
			<volume>27</volume>
			<issue>2</issue>
			<fpage>433</fpage>
			<lpage>450</lpage>
			<history>
				<date date-type="received">
					<day>01</day>
					<month>01</month>
					<year>2015</year>
				</date>
				<date date-type="accepted">
					<day>01</day>
					<month>04</month>
					<year>2015</year>
				</date>
			</history>
			<permissions>
				<copyright-statement>Vilnius University</copyright-statement>
				<copyright-year>2016</copyright-year>
			</permissions>
			<abstract>
				<p>We propose a new hybrid approach to solve the unbounded integer knapsack problem (UKP), where valid inequalities are generated based on intermediate solutions of an equivalent forward dynamic programming formulation. These inequalities help tighten the initial LP relaxation of the UKP, and therefore improve the overall computational efficiency. We also extended this approach to solve the multi-dimensional unbounded knapsack problem (d-UKP). Computational results demonstrate the effectiveness of our approach on both problems.</p>
			</abstract>
			<kwd-group>
				<label>Keywords</label>
				<kwd>integer programming</kwd>
				<kwd>dynamic programming</kwd>
				<kwd>unbounded knapsack problem</kwd>
				<kwd>valid inequalities</kwd>
			</kwd-group>
		</article-meta>
	</front>
</article>
