本文擴展 Mordane 等人 (2004) 所發展的理論利用Padé [2,2] 近似展開演進型緩坡方程式之輻射邊界條件，並以 Rojanakamthorn (1989) 波浪通過透水介質理論為基礎重新探討波浪大角度通過透水結構物之波浪變形，包括波浪通過透水介質的淺化、折射、繞射、碎波與能量消散等效應。文中首先以實驗數據驗證本文模式之適用性，再以各種不同入射角度探討波浪大角度入射之問題。本文模式與波浪通過透水介質之試驗數據比較，發現文中結果與實驗數據有良好的一致性。同時，本文針對不同角度的入射，探討邊界消波情況，進而比較模式之通用性。最後，本文將模式應用於花蓮南北濱海岸之實例計算，獲得合理之波場分佈。

　　In this paper, following the proceduce of the parabolic formulation using Padé [2,2] approximation of the propagation equation for water waves outlined by Mordane et al. (2004), the evolution equation of mild-slope equation is extended to describe combined wave refraction and diffraction propagating over porous media with large angle incidences. The model, which includes wave-porous media interaction, wavebreaking and dissipation, was developed to account for wave propagation on porous media based on Rojanakamthorn’s (1989) equation. The model is first verified by experiments for waves passing over porous media. Reasonably good agreements are obtained in terms of free surface displacement. Computational examples are provided to show the improvement in the higher-order Padé [2,2] approximation relative to the existing lower-order approximation.

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