著者

持田 真之

出版者

一般社団法人日本機械学会

雑誌

日本機械学會誌 (ISSN:00214728)

巻号頁・発行日

vol.115, no.1126, pp.632-633, 2012-09-05

著者

大上 芳文 赤松 映明

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. B編 (ISSN:03875016)

巻号頁・発行日

vol.55, no.510, pp.298-305, 1989-02-25

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A numerical investigation is carried out to examine the validity of the unsteady Kutta condition presented by many authors. Using a vortex method with a diffusion velocity model, the flow under a transient and oscillating motion of a NACA 0012 airfoil at Re=10000 is calculated. It is found that after the airfoil starts impulsively from rest, the rear stagnation point moves to the trailing edge instantly. Then the angle between the stream line from the trailing edge and the edge bisector decreases from 90° to 10° for the nondimensional time 0 to 0.1. After that time, the classical Kutta condition gradually becomes satisfied. In an oscillating motion, the rear stagnation point is always on the trailing edge and the amplitude of the angle of stream line direction from the trailing edge increases with the frequency. This result shows that the classical Kutta condition is always violated in an oscillating motion.

著者

長屋 幸助 湯澤 秀人 村上 岩範

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. C編 (ISSN:03875024)

巻号頁・発行日

vol.65, no.640, pp.4653-4659, 1999-12-25

被引用文献数

2

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Since a commutator of the DC-motor is divided into a number of segments to have the torque in the circumference direction, the currents in the coils of the rotor vary and have alternative waves during the rotor rotation even in a constant input voltage. The currents become sharp waves, so that they have high frequency component. This implies that the rotor shaft and the case of motor are excited electromagnetic forces with high frequency components. Since high frequency noises are loud when they are input to human ears, so that when high frequency vibrations are suppressed, noises become small. From the situation, this paper discusses a method of noise reduction of Dc Motor. In the method, the current waves are controlled to be sinusoidal waves. The method and the control algorithm are given. In order to validate the method, experimental tests are carried out. It is proven that our method is applicable to the motor noise control.

著者

太田 有 大田 英輔 斎藤 純夫

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. B編 = Transactions of the Japan Society of Mechanical Engineers. B (ISSN:03875016)

巻号頁・発行日

vol.68, no.671, pp.2056-2063, 2002-07-25

参考文献数

14

被引用文献数

1

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Active cancellation of noise source of higher-order blade-passing frequency noise, abbreviated to BPF noise, radiated from a centrifugal blower is conducted. The extents of noise sources of 2nd-and 3rd-order BPF components were determined by measuring a cross-correlation function between the data of the acoustic pressure measured at blower inlet and the pressure fluctuation on the scroll surface. The effective noise sources of these higher-order BPF components exist on the volute side surface of scroll relatively apart from the cut off apex, and vary irregularly with operating conditions of the blower. While the noise source of fundamental BPF lies on the vicinity of the cut off apex as usually expected. Oscillating the volute side surface of the cut off, i.e. the effective noise source of higher-order BPF components, directly by piezoelectric actuators, sound pressure level of higher-order BPF components can be reduced more than 15 decibels, and discrete tone disappears completely from power spectra of the blower radiated noise.

著者

鈴木 智 野波 健蔵 酒井 悟

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. C編 (ISSN:03875024)

巻号頁・発行日

vol.72, no.721, pp.2795-2802, 2006-09-25

被引用文献数

2

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In this paper, we design a trajectory following controller by using model following based sliding mode control for small-scale unmanned helicopter. Firstly, we derive reference model that shows an ideal response. This reference model follows continuous trajectory like a circular trajectory without delay. Secondly, we design the model following based sliding mode controller that makes the response of real system follow the response of reference model. Lastly, we show the validity of the controller by the simulation and experiment.

著者

秋庭 義明 田中 啓介 村雨 勇治

出版者

一般社団法人日本機械学会

雑誌

年次大会講演論文集 : JSME annual meeting

巻号頁・発行日

vol.2003, no.1, pp.135-136, 2003-08-05

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A bearing steel (JIS SUJ2) and nickel chromium molybden steel (SNCM439) were fatigued with the ultrasonic fatigue-testing machine (20kHz) in laboratory air. In the very long-life regime, the decline of fatigue limit was seen. The origins of crack initiation were mostly internal inclusions. However, even when the specimen broke in a long life region, some cracks were initiated from specimen surface. Fracture surface were observed with a scanning electron microscope (SEM). The fish-eyes were observed in the specimens broken from the internal inclusions. The fracture surface could be divided into three regions. The first region surrounding inclusion was a facet area. The crack propagation in the facet region was Stage A and the crack propagation outside the facet region was Stage B. When the fatigue cracks reached the specimen surface, the fatigue cracks propagated as surface cracks. The crack propagation rate in each region was estimated to be a power function of the stress intensity range. Fatigue life was calculated by integrating with the crack propagation laws determined from the data obtained for the rotating bending. The predicted fatigue life agrees with the experimental result.

著者

田中 啓介 秋庭 義明 村雨 勇治

出版者

一般社団法人日本機械学会

雑誌

東海支部総会講演会講演論文集

巻号頁・発行日

vol.2004, no.53, pp.83-84, 2004-03-01

著者

川合 政人 三上 貞芳 切明 隆司

出版者

一般社団法人日本機械学会

雑誌

ロボティクス・メカトロニクス講演会講演概要集

巻号頁・発行日

vol.2006, pp."2A1-E22(1)"-"2A1-E22(3)", 2006

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Recently, the demand of exhaust gas purification to a car is increasing. A diesel particulate filter (DPF) is promising as a solution for exhaust gas from a diesel engine of an in-use vehicle. However, under a condition of low load such as running in a city area, DPF cannot demonstrate an original performance. In order to demonstrate an original performance, it is required for a vehicle to exhaust gas which temperature should be more than fixed. Therefore, we try to raise exhaust gas temperature by restricting the flux of a valve where air inhales and gas exhausts. We use the reinforcement learning as our target is an in-use vehicle with an individual difference. And, we apply tile coding (TC) for controlling the valve in order to have the reinforcement learning cope with the extensive search space.

著者

高橋 寛 塩野 功 大場 博

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.49, no.443, pp.876-882, 1983-07-25

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アルミニウム円管の引張内圧複合負荷試験により,応力平面(π平面)第一印象における比例負荷試験を行い,各方向の応力ひずみ曲線を,単一の曲線に統一するための相当応力相当ひずみを求め,相当応力一定の曲面が降伏曲面であることの実験的検証を行った.

著者

徳岡 辰雄

出版者

一般社団法人日本機械学会

雑誌

日本機械学會誌 (ISSN:00214728)

巻号頁・発行日

vol.88, no.796, pp.253-259, 1985-03-05

著者

西村 誠一

出版者

一般社団法人日本機械学会

雑誌

日本機械学會誌 (ISSN:00214728)

巻号頁・発行日

vol.88, no.805, pp.1404-1411, 1985-12-05

被引用文献数

1

著者

甲藤 好郎 菊池 浩平

出版者

一般社団法人日本機械学会

雑誌

日本機械学會誌 (ISSN:00214728)

巻号頁・発行日

vol.75, no.639, 1972-04

著者

高原 憲一

出版者

一般社団法人日本機械学会

雑誌

日本機械学會誌 (ISSN:00214728)

巻号頁・発行日

vol.105, no.1002, 2002-05-05

著者

寺沢 憲 久納 孝彦 水野 正夫

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.47, no.414, pp.113-122, 1981-02-25

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著者が提唱した超音波加熱による熱処理の原理は, 材料を超音波振動させた際に, 材料自身の内部摩擦により生じた熱を利用することにある. 本研究の目的は超音波加熱の実用性, はん用性を広げることにある. 材料に種々のおもりをふかし, 加熱の位置, 共振周波数などの変化を調べた結果, 材料の長さおよび加熱部の位置を任意に選ぶことが可能になった. 又, 超音波熱処理の一環として, 超音波加熱による焼きもどしを試みた.

著者

尾上 英雄 佐野 典秀 高橋 亮一

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. C編 (ISSN:03875024)

巻号頁・発行日

vol.60, no.580, pp.4168-4174, 1994-12-25

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It is important to. analyze the human task in sports such as tennis games. In this paper, a fuzzy tool for evaluating of tasks in a tennis game has been proposed based on a mathematical model and questionnaires issued to players themselves. The present method is capable of calculating human performance by summing up the fuzzy-measured PSF (performance shaping factor). This elicits the two dominant PSFs with a modified fuzzy measure learning identification algorithm (FLIA) to describe the ill-defined process of human activity in tennis games. FLIA reduces a set of PSFs until human tasks are represented clearly, and groupings of tasks are illustrated on a two-dimensional map of the dominant PSF. Characteristics of groups among players of different levels are then studied via the cluster analysis.

著者

藤田 恭伸 アレクサンダー ロペス

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. B編 (ISSN:03875016)

巻号頁・発行日

vol.61, no.588, pp.3044-3051, 1995-08-25

被引用文献数

3

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Experimental data of liquid and vapor flows of R 113 for Re=5000〜400000 were obtained for both a plain tube and snugly fitted twisted tape insert tubes. No evidence of tape fin effects was found in the heat transfer characteristics of a stainless steel tape insert when compared to a Teflon tape insert. For twist ratios γ = 5.9, 10.0 and 16.0, improvements in heat transfer of up to 35% were observed. Based on a simple consideration of the heat transfer enhancement mechanisms of twisted tape inserts, a Dittus and Boelter-type correlation for a plain tube was modified to include twisted tape effects. For such a case, use of available plain-tube data was recommended to maximize the accuracy of the proposed correlation. The trade-off between pressure loss and heat transfer enhancement was considered before determining the overall desirability of twisted tape inserts.

著者

日比 一郎

出版者

一般社団法人日本機械学会

雑誌

日本機械学會誌 (ISSN:00214728)

巻号頁・発行日

vol.63, no.494, 1960-03-05

著者

川口 太生 谷杉 竜宏 中園 与一 村上 俊太郎

出版者

一般社団法人日本機械学会

雑誌

日本機械学会九州支部講演論文集

巻号頁・発行日

vol.2001, pp.155-156, 2001-10-12

著者

坂本 二郎

出版者

一般社団法人日本機械学会

雑誌

日本機械学會誌 (ISSN:00214728)

巻号頁・発行日

vol.106, no.1015, 2003-06-05

著者

MURAKAMI Teruo

出版者

一般社団法人日本機械学会

雑誌

JSME international journal. Ser. 3, Vibration, control engineering, engineering for industry (ISSN:09148825)

巻号頁・発行日

vol.33, no.4, pp.465-474, 1990-12-15

被引用文献数

9 11

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Natural joints exhibiting excellent performance under reciprocating slow speed and high loading conditions have a prominent lubrication mechanism as an adaptive multimode lubrieation, where elastohydrodynamic fluid film plays the main role supported by various supplimental lubrication mechanisms. In contrast, most of the existing joint prostheses operate not under fluid film but under mixed lubrication, which induces some tribological problems such as loosening and wear. Thus, recent investigations on the lubrication mechanisms in natural synovial joints and total replacement joints are reviewed, and then subjects on lubrication and wear in joint prostheses and optimum design of joint prostheses with artifieial cartilage are discussed.