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    <id>104</id>
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    <language>eng</language>
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    <edition/>
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    <type>reportzib</type>
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    <completedDate>1993-03-22</completedDate>
    <publishedDate>1993-03-22</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">Adaptive Multilevel-Methods for Obstacle Problems in Three Space Dimensions.</title>
    <abstract language="eng">We consider the discretization of obstacle problems for second order elliptic differential operators in three space dimensions by piecewise linear finite elements. Linearizing the discrete problems by suitable active set strategies, the resulting linear sub--problems are solved iteratively by preconditioned cg--iterations. We propose a variant of the BPX preconditioner and prove an $O(j)$ estimate for the resulting condition number. To allow for local mesh refinement we derive semi--local and local a posteriori error estimates. The theoretical results are illustrated by numerical computations.</abstract>
    <identifier type="serial">SC-93-08</identifier>
    <identifier type="opus3-id">103</identifier>
    <identifier type="urn">urn:nbn:de:0297-zib-1049</identifier>
    <enrichment key="SourceTitle">Appeared in: W. Hackbusch, G. Wittum (eds.) Adaptive Methods - Algorithms, Theory, and Computations. Braunschweig: Vieweg 1994. pp. 120-142</enrichment>
    <author>Bodo Erdmann</author>
    <author>Ronald H. W. Hoppe</author>
    <author>Ralf Kornhuber</author>
    <series>
      <title>ZIB-Report</title>
      <number>SC-93-08</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/104/SC-93-08.ps</file>
    <file>https://opus4.kobv.de/opus4-zib/files/104/SC-93-08.pdf</file>
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