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  <doc>
    <id>8232</id>
    <completedYear/>
    <publishedYear>2021</publishedYear>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst>77</pageFirst>
    <pageLast>86</pageLast>
    <pageNumber/>
    <edition/>
    <issue/>
    <volume>1</volume>
    <type>conferenceobject</type>
    <publisherName/>
    <publisherPlace/>
    <creatingCorporation/>
    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>--</completedDate>
    <publishedDate>--</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">An LP-based heuristic for Inspector Scheduling</title>
    <abstract language="eng">We present a heuristic based on linear programming (LP) for the&#13;
integrated tour and crew roster planning of toll enforcement inspectors. Their&#13;
task is to enforce the proper paying of a distance-based toll on German motorways. This leads to an integrated tour planning and duty rostering problem; it&#13;
is called Toll Enforcement Problem (TEP). We tackle the TEP by a standard&#13;
multi-commodity flow model with some extensions in order to incorporate the&#13;
control tours.&#13;
The heuristic consists of two variants. The first, called Price &amp; Branch, is&#13;
a column generation approach to solve the model’s LP relaxation by pricing&#13;
tour and roster arc variables. Then, we compute an integer feasible solution&#13;
by restricting to all variables that were priced. The second is a coarse-to-fine approach. Its basic idea is projecting variables to an aggregated variable&#13;
space, which is much smaller. The aim is to spend as much algorithmic effort&#13;
in this coarse model as possible. For both heuristic procedures we will show&#13;
that feasible solutions of high quality can be computed even for large scale industrial instances.</abstract>
    <parentTitle language="eng">Proceedings of the 13th International Conference on the Practice and Theory of Automated Timetabling - PATAT 2021: Volume I</parentTitle>
    <identifier type="url">https://patatconference.org/patat2020/proceedings/</identifier>
    <enrichment key="PeerReviewed">yes</enrichment>
    <enrichment key="opus.source">publish</enrichment>
    <author>Gerwin Gamrath</author>
    <submitter>Elmar Swarat</submitter>
    <author>Markus Reuther</author>
    <author>Thomas Schlechte</author>
    <author>Elmar Swarat</author>
    <collection role="persons" number="schlechte">Schlechte, Thomas</collection>
    <collection role="persons" number="swarat">Swarat, Elmar</collection>
    <collection role="projects" number="TOLLCONTROLOPT">TOLLCONTROLOPT</collection>
    <collection role="persons" number="reuther">Reuther, Markus</collection>
    <collection role="institutes" number="neo">Network Optimization</collection>
  </doc>
</export-example>
