著者

鈴木 秀人 ? 偉民 永井 邦和 松山 健也 伊藤 吉保 柴田 良一

出版者

一般社団法人日本機械学会

雑誌

日本機械学會論文集. A編 (ISSN:03875008)

巻号頁・発行日

vol.61, no.585, pp.894-899, 1995-05-25

被引用文献数

20 5

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An influence of cooling rate on the fatigue reliability of aluminum alloy castings (AC4CH) was investigated. The results obtained were as follows : (1) As the cooling rate of AC4CH was increased, the porosities and the microstructure were controlled fine. (2) The fatigue strength of AC4CH produced through rapid cooling rate was superior to that produced through slow cooling rate, specially on the fatigue limit (N=10^7). (3) The effect of stress gradient on the fatigue limit is due to the probability that the maximum stress can put on the largest porosity in the specimen. (4) Micro porous defects were always observed at the origin of fatigue crack. Then, it could be interpreted that the fatigue life was related to the size of porous defect, based on fracture mechanics. (5) From the above relation and the statistical analysis on the size of porous defect, the fatigue limit of 99% remaining probability could be estimated.

著者

柴田 良一 加藤史郎 島岡 俊輔 中澤 祥二

出版者

一般社団法人情報処理学会

雑誌

情報処理学会論文誌数理モデル化と応用(TOM) (ISSN:18827780)

巻号頁・発行日

vol.47, no.1, pp.144-150, 2006-02-15

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工学的最適化問題において,網羅的に設計変数間の影響を調べるためには,すべての組合せを計算する必要があり,これまでの最適化手法とは異なる「全数計算」手法が有効である.全数計算では,可能な限りすべての組合せに対して評価関数を計算することが必要であり,著しく高性能な計算能力が必要となる.これに対して,近年注目を集めているグリッドコンピューティングシステムでは,複数の計算機を統合して,高い計算能力を実現することが可能である.そこで本研究では,グリッドシステムを活用して,全数計算による建築構造計算支援を目標として,その実証的研究を行う.In this research, a 1CD-Linux system (S1GEonKNOPPIX) for building grid computing systems has been developed, aiming to verify the distributed processing capability of the grid using this for structural optimization. First, fundamental numerical analysis throughput was examined and the problem scale of the corresponding large structural analysis was decided. Next, the corresponding throughput to the optimization problem was examined paying attention to the oscillation characteristic of a structure as concrete application, was examined. The test results proved the effectiveness of this grid computing system for complete count analysis of structural optimization.