再這一篇文章裡, 我們去探討一個航空動態震動系統的極點配置問題. 不同於古典的Strum-Liouville特徵值問題, 我們面對的是一個三次特徵值問題. 同時我們也去探討這個三次特徵值問題的極點分佈.

We study a pole assignment problem by multiple-input state feedback control arising from a one dimensional vibrating system with aerodynamic effect. We derive explicit force terms which can reassign part of the spectrum to desired values while leaving the remaining spectrum unchanged. Unlike the classical Sturm-Liouville eigenvalue problem, the associated eigenvalue
problem is cubic in the eigenvalue variable and has new interesting math-ematical features. The spectrum of the associated noncompact operator is shown to be contained in the union of a real interval and a countable isolated set. This sheds light on the adjustment of model parameters.

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