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<a name = "hj-top"> </a><table class = "table1" id = "table11"><tr><td><table class = "DocHeader"><tr><td class = "DocHeader1" colspan = "2"><h1>Typical Optimization Tasks for Modal Analysis</h1></td></tr><tr><td class = "DocHeader4" colspan = "2"/></tr><tr><td class = "DocHeader3" colspan = "2"><table class = "DocThemeIntro" id = "table12"><tr><td class = "Intro1"><p class = "header"><p class = "abstract">
    <span class = "shortdesc">Often the design target is to increase the first eigenfrequencies
in an eigenfrequency spectrum. It is important to consider more than
the first natural eigenfrequency when
increasing the natural frequencies using optimization. Otherwise, the
first and secondary mode might switch during the optimization. </span>
</p>

</p><hr class = "header"/></td></tr><tr><td class = "Intro2"><span class = "run-in">In this section:</span><br/><ul class = "ulthemes"><li><a title = "For some optimization problems, it can be desirable that a sudden eigenfrequency is increased whereas the other eigenfrequencies are allowed to decrease as shown in the figure below (a)." href = "tso-c-usr-sizing-TasksModAna-ov.htm">Overview</a></li><li><a title = "The following shows how several lowest eigenfrequencies are increased." href = "tso-c-usr-sizing-TasksModAna-maxFirstFreq.htm">Maximization of the First Eigenfrequencies</a></li><li><a title = "Often it is needed to increase a specific eigenfrequency in the eigenfrequency spectrum belonging to a certain eigenmode. In this case, a specific eigenfrequency is defined using TYPE = DYN_FREQ." href = "tso-c-usr-sizing-TasksModAna-maxTorsFreq.htm">Maximizing the Torsional Modal Eigenfrequency</a></li></ul></td></tr></table></td></tr></table>

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