Minimization of Functional Majorant in a Posteriori Error Analysis Based on <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>H</mml:mi><mml:mtext>(div)</mml:mtext></mml:math> Multigrid-Preconditioned CG Method : Figure 4

]>Minimization of Functional Majorant in a Posteriori Error Analysis Based on <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>H</mml:mi><mml:mtext>(div)</mml:mtext></mml:math> Multigrid-Preconditioned CG Method : Figure 4

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Figure 4: Majorant values displayed versus iterations of CG and MPCG method for and meshes. For better illustration, the majorant part (the upper bound) from (2.6) and the square of the exact error, that is, (the lower bound) are displayed.