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  <doc>
    <id>790</id>
    <completedYear/>
    <publishedYear/>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst/>
    <pageLast/>
    <pageNumber/>
    <edition/>
    <issue/>
    <volume/>
    <type>reportzib</type>
    <publisherName/>
    <publisherPlace/>
    <creatingCorporation/>
    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>2004-05-07</completedDate>
    <publishedDate>2004-05-07</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">UMTS Radio Network Evaluation and Optimization beyond Snapshots</title>
    <abstract language="eng">This paper is concerned with UMTS radio network design. Our task is to reconfigure antennas and the related cells as to improve network quality. In contrast to second generation GSM networks, \emph{interference} plays a paramount role when designing third generation radio networks. A known compact formulation for assessing the interference characteristics of a radio network as coupling relations between cells based on user snapshots is generalized to statistical average load. This enables us to overcome the notorious difficulties of snapshot-based network optimization approaches. We recall a mixed-integer programming model for the network design problem that is based on user snapshots and contrast it with a new network design model based on the average coupling formulation. Exemplarily focusing on the important problem of optimizing antenna tilts, we give computational results for a fast local search algorithm and the application of a MIP solver to both models. These results demonstrate that our new average-based approaches outperform state-of-the-art snapshot models for UMTS radio network optimization.</abstract>
    <identifier type="serial">04-15</identifier>
    <identifier type="opus3-id">791</identifier>
    <identifier type="urn">urn:nbn:de:0297-zib-7903</identifier>
    <enrichment key="SourceTitle">Appeared in: Math. Meth. Oper. Res. 63(2006)1-29</enrichment>
    <author>Andreas Eisenblätter</author>
    <author>Hans-Florian Geerdes</author>
    <author>Thorsten Koch</author>
    <author>Alexander Martin</author>
    <author>Roland Wessäly</author>
    <series>
      <title>ZIB-Report</title>
      <number>04-15</number>
    </series>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>UMTS</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Network planning</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Network design</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="90C11">Mixed integer 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/790/ZR-04-15.ps</file>
    <file>https://opus4.kobv.de/opus4-zib/files/790/ZR-04-15.pdf</file>
  </doc>
  <doc>
    <id>615</id>
    <completedYear/>
    <publishedYear/>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst/>
    <pageLast/>
    <pageNumber/>
    <edition/>
    <issue/>
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    <type>reportzib</type>
    <publisherName/>
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    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>2000-12-12</completedDate>
    <publishedDate>2000-12-12</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">Frequency Planning and Ramifications of Coloring</title>
    <abstract language="eng">This paper surveys frequency assignment problems coming up in planning wireless communication services. It particularly focuses on cellular mobile phone systems such as GSM, a technology that revolutionizes communication. Traditional vertex coloring provides a conceptual framework for the mathematical modeling of many frequency planning problems. This basic form, however, needs various extensions to cover technical and organizational side constraints. Among these ramifications are $T$-coloring and list coloring. To model all the subtleties, the techniques of integer programming have proven to be very useful. The ability to produce good frequency plans in practice is essential for the quality of mobile phone networks. The present algorithmic solution methods employ variants of some of the traditional coloring heuristics as well as more sophisticated machinery from mathematical programming. This paper will also address this issue. Finally, this paper discusses several practical frequency assignment problems in detail, states the associated mathematical models, and also points to public electronic libraries of frequency assignment problems from practice. The associated graphs have up to several thousand nodes and range from rather sparse to almost complete.</abstract>
    <identifier type="serial">00-47</identifier>
    <identifier type="opus3-id">616</identifier>
    <identifier type="urn">urn:nbn:de:0297-zib-6152</identifier>
    <enrichment key="SourceTitle">Appeared in: Discussiones Mathematicae, Graph Theory 22 (2002) 51-88</enrichment>
    <author>Andreas Eisenblätter</author>
    <author>Martin Grötschel</author>
    <author>Arie M.C.A. Koster</author>
    <series>
      <title>ZIB-Report</title>
      <number>00-47</number>
    </series>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>frequency assignment</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>graph coloring</value>
    </subject>
    <collection role="ddc" number="000">Informatik, Informationswissenschaft, allgemeine Werke</collection>
    <collection role="msc" number="05-02">Research exposition (monographs, survey articles)</collection>
    <collection role="msc" number="05C15">Coloring of graphs and hypergraphs</collection>
    <collection role="msc" number="05C90">Applications [See also 68R10, 81Q30, 81T15, 82B20, 82C20, 90C35, 92E10, 94C15]</collection>
    <collection role="msc" number="90-02">Research exposition (monographs, survey articles)</collection>
    <collection role="institutes" number="">ZIB Allgemein</collection>
    <collection role="persons" number="groetschel">Grötschel, Martin</collection>
    <collection role="projects" number="eplus-FAP">eplus-FAP</collection>
    <file>https://opus4.kobv.de/opus4-zib/files/615/ZR-00-47.ps</file>
    <file>https://opus4.kobv.de/opus4-zib/files/615/ZR-00-47.pdf</file>
  </doc>
  <doc>
    <id>676</id>
    <completedYear/>
    <publishedYear/>
    <thesisYearAccepted/>
    <language>deu</language>
    <pageFirst/>
    <pageLast/>
    <pageNumber/>
    <edition/>
    <issue/>
    <volume/>
    <type>reportzib</type>
    <publisherName/>
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    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>2002-02-15</completedDate>
    <publishedDate>2002-02-15</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="deu">Frequenzplanung im Mobilfunk</title>
    <abstract language="deu">Telekommunikation ist seit Jahren \glqq in\grqq. Zunächst gab es einen enormen Aufschwung; neue Technologien und Dienste haben eine überwältigende, nicht vorhersehbare Akzeptanz gefunden. Derzeit ist -- ausgelöst durch die UMTS-Lizenzversteigerungen, Rezessions- und Sättigungstendenzen -- eine Krise zu verzeichnen. Viele (auch wir) sind davon überzeugt, dass technischer Fortschritt und nützliche Dienste demnächst die Stimmung wieder ändern werden. Wenigen ist allerdings bewusst, welche Rolle Mathematik bei der Entwicklung und dem effizienten Einsatz vieler der neuen Kommunikationstechnologien spielt. In diesem Artikel soll kein Überblick über diesen umfangreichen Themenkreis gegeben werden. Wir zeigen lediglich an einem konkreten Beispiel aus dem Mobilfunk, der Frequenzplanung in GSM-Funknetzen, was man durch geeignete Modellierung der praktischen Fragestellung und den Einsatz problemadäquater Algorithmen erreichen kann.</abstract>
    <identifier type="serial">02-09</identifier>
    <identifier type="opus3-id">677</identifier>
    <identifier type="urn">urn:nbn:de:0297-zib-6762</identifier>
    <enrichment key="SourceTitle">Erschienen in: DMV-Mitteilungen 1 (2002) S. 18-25</enrichment>
    <author>Andreas Eisenblätter</author>
    <author>Martin Grötschel</author>
    <author>Arie M.C.A. Koster</author>
    <series>
      <title>ZIB-Report</title>
      <number>02-09</number>
    </series>
    <subject>
      <language>deu</language>
      <type>uncontrolled</type>
      <value>Telekommunikation</value>
    </subject>
    <subject>
      <language>deu</language>
      <type>uncontrolled</type>
      <value>Frequenzplanung</value>
    </subject>
    <subject>
      <language>deu</language>
      <type>uncontrolled</type>
      <value>Mobilfunk</value>
    </subject>
    <subject>
      <language>deu</language>
      <type>uncontrolled</type>
      <value>GSM-Funknetze</value>
    </subject>
    <collection role="ddc" number="000">Informatik, Informationswissenschaft, allgemeine Werke</collection>
    <collection role="msc" number="05-02">Research exposition (monographs, survey articles)</collection>
    <collection role="msc" number="90-02">Research exposition (monographs, survey articles)</collection>
    <collection role="institutes" number="">ZIB Allgemein</collection>
    <collection role="persons" number="groetschel">Grötschel, Martin</collection>
    <file>https://opus4.kobv.de/opus4-zib/files/676/ZR-02-09.ps</file>
    <file>https://opus4.kobv.de/opus4-zib/files/676/ZR-02-09.pdf</file>
  </doc>
  <doc>
    <id>954</id>
    <completedYear/>
    <publishedYear/>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst/>
    <pageLast/>
    <pageNumber/>
    <edition/>
    <issue/>
    <volume/>
    <type>reportzib</type>
    <publisherName/>
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    <creatingCorporation/>
    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>2007-05-22</completedDate>
    <publishedDate>2007-05-22</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">Reconciling Theory and Practice: A Revised Pole Equation for W-CDMA Cell Powers</title>
    <abstract language="eng">The performance evaluation of W-CDMA networks is intricate as cells are strongly coupled through interference. Pole equations have been developed as a simple tool to analyze cell capacity. Numerous scientific contributions have been made on their basis. In the established forms, the pole equations rely on strong assumptions such as homogeneous traffic, uniform users, and constant downlink orthogonality factor. These assumptions are not met in realistic scenarios. Hence, the pole equations are typically used during initial network dimensioning only. Actual network (fine-) planning requires a more faithful analysis of each individual cell's capacity. Complex analytical analysis or Monte-Carlo simulations are used for this purposes. In this paper, we generalize the pole equations to include inhomogeneous data. We show how the equations can be parametrized in a cell-specific way provided the transmit powers are known. This allows to carry over prior results to realistic settings. This is illustrated with an example: Based on the pole equation, we investigate the accuracy of average snapshot'' approximations for downlink transmit powers used in state-of-the-art network optimization schemes. We confirm that the analytical insights apply to practice-relevant settings on the basis of results from detailed Monte-Carlo simulation on realistic datasets.</abstract>
    <identifier type="serial">07-11</identifier>
    <identifier type="opus3-id">954</identifier>
    <identifier type="urn">urn:nbn:de:0297-zib-9543</identifier>
    <enrichment key="SourceTitle">Appeared in: Proc. MsWiM’07, 2007</enrichment>
    <author>Hans-Florian Geerdes</author>
    <author>Andreas Eisenblätter</author>
    <series>
      <title>ZIB-Report</title>
      <number>07-11</number>
    </series>
    <collection role="ddc" number="000">Informatik, Informationswissenschaft, allgemeine Werke</collection>
    <collection role="institutes" number="">ZIB Allgemein</collection>
    <file>https://opus4.kobv.de/opus4-zib/files/954/ZR-07-11.pdf</file>
    <file>https://opus4.kobv.de/opus4-zib/files/954/ZR-07-11.ps</file>
  </doc>
  <doc>
    <id>3251</id>
    <completedYear>2005</completedYear>
    <publishedYear>2005</publishedYear>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst>1</pageFirst>
    <pageLast>29</pageLast>
    <pageNumber/>
    <edition/>
    <issue>1</issue>
    <volume>63</volume>
    <type>article</type>
    <publisherName/>
    <publisherPlace/>
    <creatingCorporation/>
    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>--</completedDate>
    <publishedDate>--</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">UMTS Radio Network Evaluation and Optimization beyond Snapshots</title>
    <parentTitle language="eng">Mathematical Methods of Operations Research</parentTitle>
    <identifier type="doi">10.1007/s00186-005-0002-z</identifier>
    <identifier type="url">http://opus.kobv.de/zib/volltexte/2004/791/</identifier>
    <enrichment key="PreprintUrn">urn:nbn:de:0297-zib-7903</enrichment>
    <author>Andreas Eisenblätter</author>
    <author>Hans-Florian Geerdes</author>
    <author>Thorsten Koch</author>
    <author>Alexander Martin</author>
    <author>Roland Wessäly</author>
    <collection role="institutes" number="optimization">Mathematical Optimization</collection>
    <collection role="persons" number="koch">Koch, Thorsten</collection>
    <collection role="projects" number="MATHEON-B4:UMTS">MATHEON-B4:UMTS</collection>
    <collection role="institutes" number="aopt">Applied Optimization</collection>
  </doc>
  <doc>
    <id>3185</id>
    <completedYear>2008</completedYear>
    <publishedYear>2008</publishedYear>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst>40</pageFirst>
    <pageLast>46</pageLast>
    <pageNumber/>
    <edition/>
    <issue>6</issue>
    <volume>35</volume>
    <type>article</type>
    <publisherName/>
    <publisherPlace/>
    <creatingCorporation/>
    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>--</completedDate>
    <publishedDate>--</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">Planning UMTS Radio Networks</title>
    <parentTitle language="eng">OR/MS Today</parentTitle>
    <identifier type="url">http://www.lionhrtpub.com/orms/orms-12-08/frradio.html</identifier>
    <author>Andreas Eisenblätter</author>
    <author>Hans-Florian Geerdes</author>
    <author>Martin Grötschel</author>
    <collection role="institutes" number="optimization">Mathematical Optimization</collection>
    <collection role="persons" number="groetschel">Grötschel, Martin</collection>
    <collection role="institutes" number="aopt">Applied Optimization</collection>
  </doc>
  <doc>
    <id>3118</id>
    <completedYear>1998</completedYear>
    <publishedYear>1998</publishedYear>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst>73</pageFirst>
    <pageLast>93</pageLast>
    <pageNumber/>
    <edition/>
    <issue/>
    <volume>76</volume>
    <type>article</type>
    <publisherName>J. C. Baltzer AG, Science Publishers</publisherName>
    <publisherPlace/>
    <creatingCorporation/>
    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>--</completedDate>
    <publishedDate>--</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">Frequency assignment in cellular phone networks</title>
    <parentTitle language="eng">Annals of Operations Research</parentTitle>
    <identifier type="doi">10.1023/A:1018908907763</identifier>
    <enrichment key="PreprintUrn">urn:nbn:de:0297-zib-3044</enrichment>
    <author>Ralf Borndörfer</author>
    <author>Andreas Eisenblätter</author>
    <author>Martin Grötschel</author>
    <author>Alexander Martin</author>
    <collection role="institutes" number="optimization">Mathematical Optimization</collection>
    <collection role="persons" number="borndoerfer">Borndörfer, Ralf</collection>
    <collection role="persons" number="groetschel">Grötschel, Martin</collection>
    <collection role="projects" number="eplus-FAP">eplus-FAP</collection>
    <collection role="institutes" number="aopt">Applied Optimization</collection>
  </doc>
  <doc>
    <id>3152</id>
    <completedYear>2002</completedYear>
    <publishedYear>2002</publishedYear>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst>51</pageFirst>
    <pageLast>88</pageLast>
    <pageNumber/>
    <edition/>
    <issue>22</issue>
    <volume/>
    <type>article</type>
    <publisherName/>
    <publisherPlace/>
    <creatingCorporation/>
    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>--</completedDate>
    <publishedDate>--</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">Frequency Planning and Ramifications of Coloring</title>
    <parentTitle language="eng">Discussiones Mathematicae, Graph Theory</parentTitle>
    <enrichment key="PreprintUrn">urn:nbn:de:0297-zib-6152</enrichment>
    <author>Andreas Eisenblätter</author>
    <author>Martin Grötschel</author>
    <author>Arie M.C.A. Koster</author>
    <collection role="institutes" number="optimization">Mathematical Optimization</collection>
    <collection role="persons" number="groetschel">Grötschel, Martin</collection>
    <collection role="institutes" number="aopt">Applied Optimization</collection>
  </doc>
  <doc>
    <id>3151</id>
    <completedYear>2002</completedYear>
    <publishedYear>2002</publishedYear>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst>18</pageFirst>
    <pageLast>25</pageLast>
    <pageNumber/>
    <edition/>
    <issue>1</issue>
    <volume/>
    <type>article</type>
    <publisherName/>
    <publisherPlace/>
    <creatingCorporation/>
    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>--</completedDate>
    <publishedDate>--</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">Frequenzplanung im Mobilfunk</title>
    <parentTitle language="eng">DMV-Mitteilungen</parentTitle>
    <enrichment key="PreprintUrn">urn:nbn:de:0297-zib-6762</enrichment>
    <author>Andreas Eisenblätter</author>
    <author>Martin Grötschel</author>
    <author>Arie M.C.A. Koster</author>
    <collection role="institutes" number="optimization">Mathematical Optimization</collection>
    <collection role="persons" number="groetschel">Grötschel, Martin</collection>
    <collection role="institutes" number="aopt">Applied Optimization</collection>
  </doc>
  <doc>
    <id>2963</id>
    <completedYear>2002</completedYear>
    <publishedYear>2002</publishedYear>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst>1</pageFirst>
    <pageLast>24</pageLast>
    <pageNumber/>
    <edition/>
    <issue/>
    <volume/>
    <type>bookpart</type>
    <publisherName>Kluwer</publisherName>
    <publisherPlace/>
    <creatingCorporation/>
    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>--</completedDate>
    <publishedDate>--</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">Mathematical Model of Feasible Network Configurations for UMTS</title>
    <parentTitle language="eng">Telecommunications network design and management</parentTitle>
    <author>Andreas Eisenblätter</author>
    <editor>S. G. Anandalingam</editor>
    <author>Armin Fügenschuh</author>
    <author>Thorsten Koch</author>
    <author>Arie M.C.A. Koster</author>
    <author>Alexander Martin</author>
    <author>Tobias Pfender</author>
    <author>Oliver Wegel</author>
    <author>Roland Wessäly</author>
    <collection role="institutes" number="optimization">Mathematical Optimization</collection>
    <collection role="persons" number="achterberg">Achterberg, Tobias</collection>
    <collection role="persons" number="fuegenschuh">Fügenschuh, Armin</collection>
    <collection role="persons" number="koch">Koch, Thorsten</collection>
    <collection role="institutes" number="aopt">Applied Optimization</collection>
  </doc>
  <doc>
    <id>2969</id>
    <completedYear>2003</completedYear>
    <publishedYear>2003</publishedYear>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst/>
    <pageLast/>
    <pageNumber/>
    <edition/>
    <issue/>
    <volume/>
    <type>other</type>
    <publisherName>IST-2000-28088 MOMENTUM Technical Report</publisherName>
    <publisherPlace/>
    <creatingCorporation/>
    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>--</completedDate>
    <publishedDate>--</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">XML Data Specification and Documentation</title>
    <author>Andreas Eisenblätter</author>
    <author>Armin Fügenschuh</author>
    <author>Hans-Florian Geerdes</author>
    <author>Thorsten Koch</author>
    <author>Ulrich Türke</author>
    <author>Ellen Meijerink</author>
    <collection role="institutes" number="optimization">Mathematical Optimization</collection>
    <collection role="persons" number="fuegenschuh">Fügenschuh, Armin</collection>
    <collection role="persons" number="koch">Koch, Thorsten</collection>
    <collection role="projects" number="MOMENTUM">MOMENTUM</collection>
    <collection role="institutes" number="aopt">Applied Optimization</collection>
  </doc>
  <doc>
    <id>2958</id>
    <completedYear>2004</completedYear>
    <publishedYear>2004</publishedYear>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst/>
    <pageLast/>
    <pageNumber/>
    <edition/>
    <issue/>
    <volume/>
    <type>conferenceobject</type>
    <publisherName/>
    <publisherPlace/>
    <creatingCorporation/>
    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>--</completedDate>
    <publishedDate>--</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">Integer Programming Methods for UMTS Radio Network Planning</title>
    <parentTitle language="eng">Proceedings of the WiOpt’04, Cambridge, UK</parentTitle>
    <author>Andreas Eisenblätter</author>
    <author>Armin Fügenschuh</author>
    <author>Hans-Florian Geerdes</author>
    <author>Daniel Junglas</author>
    <author>Thorsten Koch</author>
    <author>Alexander Martin</author>
    <collection role="institutes" number="optimization">Mathematical Optimization</collection>
    <collection role="persons" number="fuegenschuh">Fügenschuh, Armin</collection>
    <collection role="persons" number="koch">Koch, Thorsten</collection>
    <collection role="institutes" number="aopt">Applied Optimization</collection>
  </doc>
</export-example>
