<?xml version="1.0" encoding="utf-8"?>
<export-example>
  <doc>
    <id>817</id>
    <completedYear/>
    <publishedYear/>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst/>
    <pageLast/>
    <pageNumber/>
    <edition/>
    <issue/>
    <volume/>
    <type>reportzib</type>
    <publisherName/>
    <publisherPlace/>
    <creatingCorporation/>
    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>2004-10-28</completedDate>
    <publishedDate>2004-10-28</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">Hierarchical Infrastructure Planning in Networks</title>
    <abstract language="eng">In this article, strategical infrastructure planning problems in the design of large-scale telecommunication networks are discussed based on experiences from three projects with industrial partners: The access network planning of the German Gigabit-Wissenschaftsnetz (G-WiN) for DFN (Verein zur Förderung eines Deutschen Forschungsnetzes e.V.), the mobile network switching center location planning project for E-Plus Mobilfunk, and the fixed network switching center location planning project for TELEKOM AUSTRIA. We introduce a mathematical model for a hierarchical multi-commodity capacitated facility location problem, present adaptions of this basic model to the specific requirements within the different projects and discuss the individual peculiarities and model decisions made. Eventually, we present and discuss computational results of three associated case studies, illustrating '"how we did the job`` with mathematical methods.</abstract>
    <identifier type="serial">04-42</identifier>
    <identifier type="opus3-id">818</identifier>
    <identifier type="urn">urn:nbn:de:0297-zib-8174</identifier>
    <enrichment key="SourceTitle">Appeared in: Proc. of the 3rd Conf. on Appl. Infrastructure Research, 9 October 2004, Berlin.  C.-F. Elmer, C. von Hirschhausen eds.</enrichment>
    <author>Thorsten Koch</author>
    <author>Roland Wessäly</author>
    <series>
      <title>ZIB-Report</title>
      <number>04-42</number>
    </series>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Facility Location</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Telecommunication</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="90B10">Network models, deterministic</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="90C90">Applications of mathematical programming</collection>
    <collection role="institutes" number="">ZIB Allgemein</collection>
    <collection role="persons" number="koch">Koch, Thorsten</collection>
    <file>https://opus4.kobv.de/opus4-zib/files/817/ZR-04-42.ps</file>
    <file>https://opus4.kobv.de/opus4-zib/files/817/ZR-04-42.pdf</file>
  </doc>
  <doc>
    <id>701</id>
    <completedYear/>
    <publishedYear/>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst/>
    <pageLast/>
    <pageNumber/>
    <edition/>
    <issue/>
    <volume/>
    <type>reportzib</type>
    <publisherName/>
    <publisherPlace/>
    <creatingCorporation/>
    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>2002-10-15</completedDate>
    <publishedDate>2002-10-15</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">Transparent optical network design with sparse wavelength conversion</title>
    <abstract language="eng">We consider the design of transparent optical networks from a practical perspective. Network operators aim at satisfying the communication demands at minimum cost. Such an optimization involves three interdependent planning issues: the dimensioning of the physical topology, the routing of lightpaths, and the wavelength assignment. Further topics include the reliability of the configuration and sparse wavelength conversion for efficient use of the capacities. In this paper, we investigate this extensive optical network design task. Using a flexible device-based model, we present an integer programming formulation that supports greenfield planning as well as expansion planning on top of an existing network. As solution method, we propose a suitable decomposition approach that separates the wavelength assignment from the dimensioning and routing. Our method in particular provides a lower bound on the total cost which allows to rate the solution quality. Computational experiments on realistic networks approve the solution approach to be appropriate.</abstract>
    <identifier type="serial">02-34</identifier>
    <identifier type="opus3-id">702</identifier>
    <identifier type="urn">urn:nbn:de:0297-zib-7017</identifier>
    <enrichment key="SourceTitle">Appeared in: Proceedings of ONDM 2003, the 7th IFIP Working Conference on Optical Network Design and Modelling, February 3-5, 2003, Budapest, Hungary. ISBN 9632064062. Pp. 61-80</enrichment>
    <author>Adrian Zymolka</author>
    <author>Arie M.C.A. Koster</author>
    <author>Roland Wessäly</author>
    <series>
      <title>ZIB-Report</title>
      <number>02-34</number>
    </series>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>optical network design</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>wavelength conversion</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>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="90C10">Integer programming</collection>
    <collection role="msc" number="90C35">Programming involving graphs or networks [See also 90C27]</collection>
    <collection role="msc" number="90C90">Applications of mathematical programming</collection>
    <collection role="institutes" number="">ZIB Allgemein</collection>
    <collection role="projects" number="OPTICALNET">OPTICALNET</collection>
    <file>https://opus4.kobv.de/opus4-zib/files/701/ZR-02-34.ps</file>
    <file>https://opus4.kobv.de/opus4-zib/files/701/ZR-02-34.pdf</file>
  </doc>
  <doc>
    <id>951</id>
    <completedYear/>
    <publishedYear/>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst/>
    <pageLast/>
    <pageNumber/>
    <edition/>
    <issue/>
    <volume/>
    <type>reportzib</type>
    <publisherName/>
    <publisherPlace/>
    <creatingCorporation/>
    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>2007-04-17</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>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>
</export-example>
