| 研究生: |
陳奕安 Chen, YI-An |
|---|---|
| 論文名稱: |
應用於淺冰近似中退化型 p-Laplace 方程之不連續有限元素法與 Anderson 加速 Discontinuous Galerkin Methods with Anderson Acceleration for Degenerate p-Laplace Equation Arising from the Shallow Ice Approximation |
| 指導教授: |
陳旻宏
Chen, Min-Hung |
| 學位類別: |
碩士 Master |
| 系所名稱: |
理學院 - 數學系應用數學碩博士班 Department of Mathematics |
| 論文出版年: | 2025 |
| 畢業學年度: | 113 |
| 語文別: | 英文 |
| 論文頁數: | 51 |
| 中文關鍵詞: | 淺冰近似 、p-Laplace方程 、不連續有限元素法 、Anderson加速 |
| 外文關鍵詞: | Shallow Ice Approximation, p-Laplace equation, Discontinuous Galerkin, Anderson acceleration |
| 相關次數: | 點閱:122 下載:8 |
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本論文首先簡要介紹冰層動力學中的淺冰近似方程。為了避免在冰層邊緣處梯度產生奇異性,可透過變數變換將其轉換為 $p$-Laplace 方程。本研究採用不連續有限元素法求解此方程。考慮到方程的退化特性,我們於數值計算中引入正則化參數 $delta$ 以避免由此性質引發的問題。此外,為加速疊代過程,我們在固定點迭代中引入Anderson加速方法,並使用阻尼參數以減緩固定點算子非收縮性所帶來的影響。最後,我們使用 FEniCS 函式庫並在 Google Colaboratory 平台上實作數值結果。
This thesis begins with a brief introduction to the shallow ice approximation (SIA) equation in ice sheet dynamics. To avoid singularities in the gradient near the ice margin, the SIA can be transformed into a $p$-Laplace equation through a change of variables. This study use the discontinuous Galerkin (DG) method to solve the equation. Considering the degenerate nature of the equation, a regularization parameter $delta$ is introduced in the numerical computation to avoid this issue. In addition, to accelerate the iterative process, we apply Anderson acceleration (AA) to the fixed-point iteration and introduce a damping parameter to reduce the effects caused by the non-contractive nature of the fixed-point operator. Finally, we implement numerical results using the FEniCS library on the Google Colaboratory platform.
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