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        <identifier>oai:drops-oai.dagstuhl.de:343</identifier>
        <datestamp>2024-03-06T11:06:23Z</datestamp>
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          <dc:title>On Layering Directed Acyclic Graphs</dc:title>
          <dc:creator>Harrigan, Martin</dc:creator>
          <dc:creator>Healy, Patrick</dc:creator>
          <dc:subject>Graph Drawing</dc:subject>
          <dc:subject>Hierarchical Drawings</dc:subject>
          <dc:subject>Layerings</dc:subject>
          <dc:subject>Minimum Dummy Nodes</dc:subject>
          <dc:description>We consider the problem of layering a directed acyclic graph with minimum dummy nodes. We present a new Integer Linear Programming (ILP) formulation of the problem based on a set of fundamental cycles in the underlying undirected graph and show that it can be solved in polynomial time. We outline some of the advantages of the formulation. Each solution defines a family of layerings with the same number of dummy nodes. We can also transform one solution into another by adding or removing certain combinations of dummy nodes, thus allowing the consideration of other aesthetics.</dc:description>
          <dc:publisher>Schloss Dagstuhl – Leibniz-Zentrum für Informatik</dc:publisher>
          <dc:contributor>Martin Harrigan and Patrick Healy</dc:contributor>
          <dc:date>2006</dc:date>
          <dc:relation>Is Part Of Dagstuhl Seminar Proceedings, Volume 5191, Graph Drawing (2006)</dc:relation>
          <dc:type>InProceedings</dc:type>
          <dc:type>Text</dc:type>
          <dc:type>doc-type:ResearchArticle</dc:type>
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          <dc:identifier>doi:10.4230/DagSemProc.05191.6</dc:identifier>
          <dc:identifier>urn:nbn:de:0030-drops-3430</dc:identifier>
          <dc:identifier>https://drops.dagstuhl.de/entities/document/10.4230/DagSemProc.05191.6</dc:identifier>
          <dc:language>eng</dc:language>
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