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2021/2 Vol.124

工部大学校の「機械学」教育機器(機械遺産第100号)

機構模型:差動歯車

年代未詳/真鍮、鉄、ガラス、木製台座/H310, W245, D235(mm)/東京大学総合研究博物館所蔵

工科大学もしくは工学部の備品番号「工キ學ニ一八五」の木札付。本模型の年代は未詳であるが、東京大学総合研究博物館には工部大学校を示すプレート付きのものを含め、近代的な機械学教育のために明治期以降に導入された機構模型が現存する。
上野則宏撮影/東京大学総合研究博物館写真提供/インターメディアテク展示・収蔵
[東京大学総合研究博物館]

バックナンバー

論文アクセスランキング

論文アクセスランキング 日本機械学会学術誌(和文) 年間アクセス数トップ10

(2019年7月~2020年6月の期間で集計) *順位の変動は2019年4月~2020年3月の期間との比較


機械学習を用いたしゅう動面状態監視システムに関する研究

橋本 優花, 本田 知己, 持田 裕介, 杉山 和彦, 中村 由美子, 高東 智佳子

日本機械学会論文集(2018) DOI:10.1299/transjsme.18-00275
Machine equipment usually comprises many mechanical elements that can fail because of functional deterioration and friction. For tribo-elements like plane bearings, it is extremely important to diagnose the abnormal conditions and prevent such parts from breakdown caused by wear. However, diagnosing tribo-elements requires expensive diagnostic equipment and expertise. This study aims to propose a cost- and time- effective system that detect the signs of breakdown during equipment operation by using machine learning to identify abnormalities. We conducted wear tests in contaminated oil and used multiple sensors to collect data regarding the friction force, the electrical contact resistance, the acoustic emission (AE) signal, and vibration. An appropriate learning sample was selected using k-fold cross-validation. The electrical contact resistance was found to contribute relatively little to the detection of abnormalities, whereas the friction coefficient contributed greatly. Furthermore, the AE signal and the vibration detected local changes on the sliding surface. Consequently, we found that machine learning can judge whether monitoring data are normal or abnormal.

MoDTC油中における水素含有DLC膜の異常摩耗メカニズム

大久保 光, 前田 寛陽, 川田 将平, 田所 千治, 佐々木 信也

日本機械学会論文集 (2018) DOI:10.1299/transjsme.17-00564
The wear acceleration mechanism of a DLC film lubricated with MoDTC solution was investigated by using in-situ and ex-situ analytical techniques: Raman spectroscopy, SEM-EDS, ToF-SIMS, and nano-indenter. From the results, the structural change of the DLC film strongly related to the formation of Mo-carbide containing tribofilms, which were much harder than DLC used in this study. Therefore, the MoDTC-induced wear acceleration of the DLC film is caused by hard Mo-carbide containing tribofilms on a counter-face steel surface.

折れ部を有する曲面の端部から発生するフィードバック音のプラズマアクチュエータを用いた制御

宮本 孟宜, 横山 博史, 飯田 明由

日本機械学会論文集 (2018) DOI:10.1299/transjsme.18-00121
Intense sound is radiated due to aeroacoustic feedback loop from a flow around the trailing edge of a curved plate with a kink shape such as a bonnet of an automobile. For the reduction of this noise, the control by a plasma actuator (PA) was investigated. The aim of this investigation is to clarify the effects of flow control by the PA on noise reduction and the noise reduction mechanism. To do this, wind tunnel experiments with a half-scale bonnet model and direct numerical simulations of flow and sound fields were performed. The investigation of the effects of the position for the installation of the PA on the control presents that the control at the position close to the flow separation point around the kink is effective for the noise reduction. Also, the control effects were compared between co-flow and counter-flow configurations regarding the direction of the mean induced flow by the actuator to the freestream. The mean velocity profiles showed that the flow separation was suppressed by the control with both configurations, while this control effect is more effective for the counter-flow configuration. The measured velocity fluctuations present that the power in broadband frequency range in the downstream of the actuator becomes larger by the control with both configurations. The predicted results show that small-scale vortices are shed near the wall around the actuator due to the large counter-flow induced flow. This introduction of the vortices and the intensification of the broadband velocity fluctuations lead to the suppression of the flow separation. Also, the development of the power of the velocity fluctuations at the fundamental frequency of the baseline tonal sound is weakened by the suppression of the flow separation. This supports the predicted results of the suppression of the two-dimensional vortices contributing to the acoustic radiation around the re-attachment point by the control. Consequently, the control can lead to the suppression of the feedback loop of the radiating mechanism of tonal sound.

4位

[NEW]

ワイヤ干渉駆動型多関節3次元アームの開発(張力伝達効率,リールの最大密度配置および先端位置精度の検討)

堀米 篤史, 山田 浩也, 洗 津, 広瀬 茂男, 遠藤 玄
日本機械学会論文集 (2017) DOI:10.1299/transjsme.16-00270

5位

[NEW]

大量生産部品のリコールを防止するための極値統計による新しい品質管理法

村上 敬宜, 町田 尚, 宮川 進, 髙城 壽雄
日本機械学会論文集 (2017) DOI:10.1299/transjsme.17-00231

6位

[NEW]

競泳キックスタートにおける蹴り出しのタイミングがスタートパフォーマンスへ与える影響

田中 貴大, 本城 豊之, 藤本 雅大, 長野 明紀, 尾関 一将, 伊坂 忠夫
日本機械学会論文集 (2020) DOI:10.1299/transjsme.19-00392

7位

[NEW]

溶射プロセスをモデル化したろうの滴下実験による急冷ひずみの測定

天野 歩, 阪口 基己, 黒川 悠, 岡嶋 芳史, 井上 裕嗣
日本機械学会論文集 (2017) DOI:10.1299/transjsme.17-00377

8位

[NEW]

石炭火力発電施設ボイラ構造物の制振技術の開発と長周期長時間地震への適応性検討

田中 剛, 藤田 聡, 皆川 佳祐, 相田 清
日本機械学会論文集 (2019) DOI:10.1299/transjsme.18-00252

9位

[↓]

Ni基超合金Alloy718合金の疲労強度に及ぼす表面加工層の影響(第2報:結晶塑性有限要素法を用いた残留応力解放の検討)

蓮沼 将太, 波田野 明日可, 泉 聡志, 酒井 信介
日本機械学会論文集 (2017) DOI:10.1299/transjsme.16-00264

10位

[NEW]

高速炉に適用する厚肉積層ゴムの研究開発(1/2縮尺厚肉積層ゴムを用いた静的載荷試験に基づく履歴モデルの構築)

深沢 剛司, 岡村 茂樹, 山本 智彦, 川崎 信史, 杣木 孝裕, 櫻井 祐, 正木 信男
日本機械学会論文集 (2018) DOI:10.1299/transjsme.17-00502

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