就物理上而言，線性單色波可透過破壞性干涉作用而被完全地抑制；在作法上我們只需將系統的原始外力拆解成幾個相似但分離的部分外力之疊加即可。同時，藉著調整部分外力之個數、個別強度與相鄰部分外力間距，我們可以進一步減低前述外力修正手段的波動抑制效果對修正參數誤差之靈敏度。
在本文中我們考慮弱非線性且弱色散參數條件下之理想勢流波動系統。為了避開不必要的複雜度，首先我們利用微擾展開方法將完整勢流理論模型簡化為一描述自由表面變形之強制Korteweg-de Vries (fKdV)模型問題。在fKdV模型問題基礎上，我們利用指數漸近方法計算被流場底部地形所激發之波動振幅，並且據以評估不同外力修正手段之強健性與參數誤差之靈敏度。結果發現，我們在本文中所提出的一套具有低誤差靈敏度特性之外力修正手段不僅在非線性系統中仍能良好運作，且其波動抑制效果與對修正間距參數誤差之容忍度皆比應用於線性波動系統時為佳。
最後，我們回歸勢流波動系統之完整理論模型，並以指數漸近方法計算弱非線性且弱色散條件下之勢流場與波動振幅，進而驗證了前述正面結論依然適用於較實際之波動系統中。

On physical grounds, linear monochromatic waves can be completely suppressed through destructive interference: technically, by modifying the original forcing into a superposition of several separated partial forcings having similar shape but differing strengths. Furthermore, the parameter error sensitivity of such input shaping methods can be significantly reduced by manipulating the total number of partial forcings, their individual strengths, and the separation distance between neighboring partial forcings.
In this thesis, we consider surface waves generated by a uniform potential flow past bottom topography. First, to simplify the analysis, the weakly nonlinear and weakly dispersive parameter regime is considered, and the full potential flow problem is reduced by perturbation expansion to the forced Kortewege-de Vries (fKdV) equation governing the free surface deformation. Based on the fKdV model, techniques of exponential asymptotics are employed to calculate the wave amplitude. The effectiveness and parameter error sensitivity of various input shaping schemes are then compared. As it turns out, an error-insensitive input shaping scheme proposed here not only works well in nonlinear systems, but also appears to be more tolerant of separation distance errors in nonlinear wave systems than in linear systems.
Encouraged by such exciting positive results, we then return to the full potential flow model, and use exponential asymptotic methods to calculate the wave amplitude in the weakly nonlinear and weakly dispersive parameter regime. Interestingly, qualitatively similar results are obtained, and we conclude that input shaping (topography modification) is an effective means for wave amplitude control.

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