改良式移動漸近線法於結構之最佳化設計

An Improved Method of Moving Asymptotes for Structural Optimization

陳景文(Jing-Wen Chen)

指導教授 ： 張永康

淡江大學/工學院/航空太空工程學系碩士班/碩士(2009年)

https://doi.org/10.6846/TKU.2009.00296

摘要

本研究應用改良式移動漸近線法於結構之最佳化設計。移動漸近線法的主要概念是將函數先以泰勒一階展開的倒數近似法，再利用兩個中介變數轉換為近似原問題之函數，並依照轉換後函數的特性配合對偶法來求得最佳值。吾人藉由改變中介變數、移動限制等參數計算規則，使搜尋過程加快以加速程式收斂效率。
數值範例中將對各種結構作分析與討論，分別以結構輕量化設計或提高結構之第一自然振動頻率為目的。本研究以ANSYS有限元素分析軟體中的APDL語法與FORTRAN程式結合成一系統程式，並使用有限差分法計算靈敏度以獲得執行移動漸近線法所需之數據。範例中驗證改良式移動漸近線法於結構之最佳化設計上可以得到比其他文獻更好的結果。

關鍵字

移動漸近線法 ； 移動限制 ； 靈敏度分析

並列摘要

An improved method of moving asymptotes was used for structural optimization in this study. The concept of moving asymptotes is to use first order Taylor series expansion to approximate an original function, and then converting it to the similar function by intermediate variable. According to the feature of the converted function and Dual method, the optimum design can be solved. By using the move limit technique to change the intermediate variable, the searching process of optimization design can be improved and the design cycle was reduced.
Optimum design of different structures will be analyzed in numerical examples. A systematic program which combined APDL with FORTRAN to calculate sensitivity and necessary data for MMA was developed in this study. The optimum design of structures by improved method of moving asymptotes was proved to be better than other references in this study.

並列關鍵字

Method of Moving Asymptotes ； Dual Method ； Sensitivity analysis

參考文獻

[12] 黃建翰， 2007， 應用逐次線性規劃法結合移動限制技術於結構最佳化設計之研究， 淡江大學航空太空工程研究所碩士論文。

[15] 柯星竹， 2006， 應用遺傳演算法與類神經網路於結構最佳化設計之研究， 淡江大學航空太空工程研究所碩士論文。

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