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  <doc>
    <id>951</id>
    <completedYear/>
    <publishedYear/>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst/>
    <pageLast/>
    <pageNumber/>
    <edition/>
    <issue/>
    <volume/>
    <type>reportzib</type>
    <publisherName/>
    <publisherPlace/>
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    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>2007-04-17</completedDate>
    <publishedDate>2007-04-17</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">On the strength of cut-based inequalities for capacitated network design polyhedra</title>
    <abstract language="eng">In this paper we study capacitated network design problems, differentiating directed, bidirected and undirected link capacity models. We complement existing polyhedral results for the three variants by new classes of facet-defining valid inequalities and unified lifting results. For this, we study the restriction of the problems to a cut of the network. First, we show that facets of the resulting cutset polyhedra translate into facets of the original network design polyhedra if the two subgraphs defined by the network cut are (strongly) connected. Second, we provide an analysis of the facial structure of cutset polyhedra, elaborating the differences caused by the three different types of capacity constraints. We present flow-cutset inequalities for all three models and show under which conditions these are facet-defining. We also state a new class of facets for the bidirected and undirected case and it is shown how to handle multiple capacity modules by Mixed Integer Rounding (MIR).</abstract>
    <identifier type="serial">07-08</identifier>
    <identifier type="opus3-id">951</identifier>
    <identifier type="urn">urn:nbn:de:0297-zib-9512</identifier>
    <author>Christian Raack</author>
    <author>Arie M.C.A. Koster</author>
    <author>Roland Wessäly</author>
    <series>
      <title>ZIB-Report</title>
      <number>07-08</number>
    </series>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>cutset-polyhedra</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>flow-cutset inequalities</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>network design</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>mixed integer programming</value>
    </subject>
    <collection role="ddc" number="000">Informatik, Informationswissenschaft, allgemeine Werke</collection>
    <collection role="msc" number="90B18">Communication networks [See also 68M10, 94A05]</collection>
    <collection role="msc" number="90C11">Mixed integer programming</collection>
    <collection role="msc" number="90C35">Programming involving graphs or networks [See also 90C27]</collection>
    <collection role="msc" number="90C57">Polyhedral combinatorics, branch-and-bound, branch-and-cut</collection>
    <collection role="institutes" number="">ZIB Allgemein</collection>
    <collection role="projects" number="BMBF-Eibone">BMBF-Eibone</collection>
    <collection role="projects" number="MATHEON-B3">MATHEON-B3</collection>
    <file>https://opus4.kobv.de/opus4-zib/files/951/ZR_07_08.pdf</file>
    <file>https://opus4.kobv.de/opus4-zib/files/951/ZR-07-08.pdf</file>
    <file>https://opus4.kobv.de/opus4-zib/files/951/ZR_07_08.ps</file>
    <file>https://opus4.kobv.de/opus4-zib/files/951/ZR-07-08.ps</file>
  </doc>
  <doc>
    <id>957</id>
    <completedYear/>
    <publishedYear/>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst/>
    <pageLast/>
    <pageNumber/>
    <edition/>
    <issue/>
    <volume/>
    <type>reportzib</type>
    <publisherName/>
    <publisherPlace/>
    <creatingCorporation/>
    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>2007-06-07</completedDate>
    <publishedDate>2007-06-07</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">Capacitated network design using general flow-cutset inequalities</title>
    <abstract language="eng">This paper deals with directed, bidirected, and undirected capacitated network design problems. Using mixed integer rounding (MIR), we generalize flow-cutset inequalities to these three link types and to an arbitrary modular link capacity structure, and propose a generic separation algorithm. In an extensive computational study on 54 instances from the Survivable Network Design Library (SNDlib), we show that the performance of cplex can significantly be enhanced by this class of cutting planes. The computations reveal the particular importance of the subclass of cutset-inequalities.</abstract>
    <identifier type="serial">07-14</identifier>
    <identifier type="opus3-id">957</identifier>
    <identifier type="urn">urn:nbn:de:0297-zib-9576</identifier>
    <author>Christian Raack</author>
    <author>Arie M.C.A. Koster</author>
    <author>Sebastian Orlowski</author>
    <author>Roland Wessäly</author>
    <series>
      <title>ZIB-Report</title>
      <number>07-14</number>
    </series>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>general flow-cutset inequalities</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>capacitated network design</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>mixed integer rounding</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>SNDlib</value>
    </subject>
    <collection role="ddc" number="000">Informatik, Informationswissenschaft, allgemeine Werke</collection>
    <collection role="msc" number="90B18">Communication networks [See also 68M10, 94A05]</collection>
    <collection role="msc" number="90C11">Mixed integer programming</collection>
    <collection role="msc" number="90C35">Programming involving graphs or networks [See also 90C27]</collection>
    <collection role="msc" number="90C57">Polyhedral combinatorics, branch-and-bound, branch-and-cut</collection>
    <collection role="institutes" number="">ZIB Allgemein</collection>
    <collection role="projects" number="MATHEON-B3">MATHEON-B3</collection>
    <file>https://opus4.kobv.de/opus4-zib/files/957/ZR-07-14.pdf</file>
    <file>https://opus4.kobv.de/opus4-zib/files/957/ZR-07-14.ps</file>
  </doc>
  <doc>
    <id>3305</id>
    <completedYear>2007</completedYear>
    <publishedYear>2007</publishedYear>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst/>
    <pageLast/>
    <pageNumber/>
    <edition/>
    <issue/>
    <volume/>
    <type>conferenceobject</type>
    <publisherName>International Network Optimization Conference</publisherName>
    <publisherPlace>Spa, Belgium</publisherPlace>
    <creatingCorporation/>
    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>--</completedDate>
    <publishedDate>--</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">Two-layer Network Design by Branch-and-Cut featuring MIP-based Heuristics</title>
    <parentTitle language="eng">Proceedings of the INOC 2007, Spa, Belgium, also ZIB Report ZR-06-47</parentTitle>
    <identifier type="url">http://www.zib.de/Publications/abstracts/ZR-06-47</identifier>
    <enrichment key="PreprintUrn">urn:nbn:de:0297-zib-9412</enrichment>
    <author>Sebastian Orlowski</author>
    <author>Arie M.C.A. Koster</author>
    <author>Christian Raack</author>
    <author>Roland Wessäly</author>
    <collection role="institutes" number="optimization">Mathematical Optimization</collection>
    <collection role="projects" number="BMBF-Eibone">BMBF-Eibone</collection>
    <collection role="institutes" number="aopt">Applied Optimization</collection>
  </doc>
  <doc>
    <id>3303</id>
    <completedYear>2007</completedYear>
    <publishedYear>2007</publishedYear>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst/>
    <pageLast/>
    <pageNumber/>
    <edition/>
    <issue/>
    <volume/>
    <type>conferenceobject</type>
    <publisherName>International Network Optimization Conference</publisherName>
    <publisherPlace>Spa, Belgium</publisherPlace>
    <creatingCorporation/>
    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>--</completedDate>
    <publishedDate>--</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">Capacitated network design using general flow-cutset inequalities</title>
    <parentTitle language="eng">Proceedings of the INOC 2007, Spa, Belgium, also ZIB Report ZR-07-14</parentTitle>
    <identifier type="url">http://www.zib.de/Publications/abstracts/ZR-07-14</identifier>
    <enrichment key="PreprintUrn">urn:nbn:de:0297-zib-9576</enrichment>
    <author>Christian Raack</author>
    <author>Arie M.C.A. Koster</author>
    <author>Sebastian Orlowski</author>
    <author>Roland Wessäly</author>
    <collection role="institutes" number="optimization">Mathematical Optimization</collection>
    <collection role="projects" number="BMBF-Eibone">BMBF-Eibone</collection>
    <collection role="institutes" number="aopt">Applied Optimization</collection>
  </doc>
  <doc>
    <id>958</id>
    <completedYear/>
    <publishedYear/>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst/>
    <pageLast/>
    <pageNumber/>
    <edition/>
    <issue/>
    <volume/>
    <type>reportzib</type>
    <publisherName/>
    <publisherPlace/>
    <creatingCorporation/>
    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>2007-06-13</completedDate>
    <publishedDate>2007-06-13</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">SNDlib 1.0--Survivable Network Design Library</title>
    <abstract language="eng">We provide information on the Survivable Network Design Library (SNDlib), a data library for fixed telecommunication network design that can be accessed at http://sndlib.zib.de. In version 1.0, the library contains data related to 22 networks which, combined with a set of selected planning parameters, leads to 830 network planning problem instances. In this paper, we provide a mathematical model for each planning problem considered in the library and describe the data concepts of the SNDlib. Furthermore, we provide statistical information and details about the origin of the data sets.</abstract>
    <identifier type="serial">07-15</identifier>
    <identifier type="opus3-id">958</identifier>
    <identifier type="urn">urn:nbn:de:0297-zib-9582</identifier>
    <enrichment key="SourceTitle">A shortened version appeared in: Proceedings of International Network Optimization Conference (INOC 2007), Spa, Belgien, April 2007</enrichment>
    <author>Sebastian Orlowski</author>
    <author>Michal Pioro</author>
    <author>Artur Tomaszewski</author>
    <author>Roland Wessäly</author>
    <series>
      <title>ZIB-Report</title>
      <number>07-15</number>
    </series>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>telecommunication network design</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>data library</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>optimization</value>
    </subject>
    <collection role="ddc" number="000">Informatik, Informationswissenschaft, allgemeine Werke</collection>
    <collection role="msc" number="90B18">Communication networks [See also 68M10, 94A05]</collection>
    <collection role="msc" number="90C11">Mixed integer programming</collection>
    <collection role="msc" number="90C35">Programming involving graphs or networks [See also 90C27]</collection>
    <collection role="institutes" number="optimization">Mathematical Optimization</collection>
    <collection role="projects" number="atesio">atesio</collection>
    <collection role="projects" number="BMBF-Eibone">BMBF-Eibone</collection>
    <collection role="projects" number="MATHEON-B3">MATHEON-B3</collection>
    <collection role="institutes" number="aopt">Applied Optimization</collection>
    <file>https://opus4.kobv.de/opus4-zib/files/958/ZR-07-15.pdf</file>
    <file>https://opus4.kobv.de/opus4-zib/files/958/ZR-07-15.ps</file>
  </doc>
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