著者

今井 康文 森田 英毅 高瀬 徹 古賀 博之

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.55, no.509, pp.147-151, 1989-01-25

被引用文献数

7 7

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Time-dependent thermal stress singularities at a semi-infinite crack tip associated with a transient temperature field have been analyzed on an infinite plate with a point heat source near the crack tip. As the heating begins, a mode I singularity increases gradually with time, but, after showing its maximum, decreases to be negative. This singularity variation causes a crack to start growing at some instance, but soon after to stop. That is, crack growth may be controlled, which is desirable for a cutting device for brittle materials. Deflection of a heating point from a crack line results in a mode II stress singularity, which also leads a crack to swerve from the original crack line. In an experiment using glass plates, a crack was successfully controlled to grow and also to branch in any angle toward the heat source as long as the heating location was kept appropriately apart from the crack tip.

著者

高瀬 徹

出版者

日本建設機械化協会

雑誌

建設の機械化 (ISSN:02855453)

巻号頁・発行日

no.266, pp.3-9, 1972-04

著者

高瀬 徹 小山 敦弘 内田 武

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.84, no.858, pp.17-00489-17-00489, 2018 (Released:2018-02-25)

参考文献数

8

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In order to design a rotating shaft, it is necessary to investigate the fatigue characteristics under the variable amplitude loading by using a rotating bending fatigue machine. However, the stress amplitude cannot be changed frequently in a commercial rotating bending fatigue machine. Therefore, the automatic loading apparatus was manufactured in order to perform the fatigue test under the repeated two-step variable amplitude loading by using the commercial rotating bending fatigue machine. In this apparatus, the load was changed by loading or unloading the weight using air pressure. The high stress amplitude and the low stress amplitude were alternately applied to the specimen in the rotating bending fatigue test under repeated two-step variable amplitude loading. Rotating bending fatigue tests were performed using heat-treated 0.45%C steel specimens. Before the fatigue tests, the performance test of the automatic loading apparatus was conducted and it was found that the apparatus was available for fatigue tests. Next, the fatigue tests under the repeated two-step variable amplitude loading were carried out based on the results in the Hi-Lo two-step loading fatigue test and then the cumulative fatigue was investigated. The total fatigue lives to failure of low stress amplitude under the repeated two-step variable amplitude loading are almost same as lives under the Hi-Lo two-step loading, but they have the longer lives as the low stress amplitudes decrease. Finally, the life prediction method for the specimens subjected to repeated two-step variable amplitude loading was proposed. The results estimated based on the proposed method were in good agreement with the experimental ones.

著者

今野 浩 周 宏傑 高瀬 徹

出版者

東京工業大学

雑誌

人文論叢 (ISSN:02896966)

巻号頁・発行日

vol.19, pp.85-94, 1993-03-05

著者

今村 浩一郎 濱住 啓之 渋谷 一彦 佐々木 誠 大和田 雄之 佐伯 暖 金井 隆夫 福原 黎児 高瀬 徹 川瀬 克行

出版者

一般社団法人映像情報メディア学会

雑誌

映像情報メディア学会技術報告 (ISSN:13426893)

巻号頁・発行日

vol.24, no.43, pp.17-22, 2000-07-27

被引用文献数

15

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地上デジタル放送におけるSFNを放送波中継で実現する場合、中継放送所の送受アンテナ間の回り込みによる発振や信号の劣化が大きな問題となる。この回り込み対策として、回路的に回り込みを打ち消す回り込みキャンセラ、ならびに、低サイドローブ特性を有する平面受信アンテナの開発を行っている。本報告では、平成12年3月に近畿地区の地上デジタル放送研究開発用共同利用施設である北淡垂水中継局を用いて行ったSFNでの放送波中継実験の結果について述べる。この実験において、回り込みキャンセラと低サイドローブ受信アンテナを併用することで、回り込み波の受信電力が親局波と同程度の厳しい条件下でも、安定に中継できることを確認した。