著者

中山 敦 嶋脇 聡 酒井 直隆 中林 正隆

出版者

一般社団法人 日本機械学会

雑誌

茨城講演会講演論文集 2013.21 (ISSN:24242683)

巻号頁・発行日

pp.219-220, 2013-09-06 (Released:2017-06-19)

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When human hand grasping an object, nail will support and restrain the deformation of finger pulp. Object is able to be grasped firmly due to the adaptation of finger pulp to the shape of grasped object. So, the nail is considered to be playing an important role in every motion of the fingertip. But the study case regarding the nail structure and it's mechanical properties are very rare. We used guitar string and applied to ways of doing experiment, such as pressing and flipping on the string.

著者

中川 良一

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会誌 (ISSN:24242675)

巻号頁・発行日

vol.63, no.492, pp.113-121, 1960-01-05 (Released:2017-06-21)

著者

吉原 裕二 細田 文典

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会誌 (ISSN:24242675)

巻号頁・発行日

vol.112, no.1092, pp.904-907, 2009-11-05 (Released:2017-06-21)

参考文献数

20

被引用文献数

1 2

著者

松繩 信太

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会誌

巻号頁・発行日

vol.43, no.285, pp.648-651, 1940

著者

林 裕介 渡辺 昌宏 原 謙介

出版者

一般社団法人 日本機械学会

雑誌

Dynamics & Design Conference 2010 (ISSN:24242993)

巻号頁・発行日

pp._260-1_-_260-6_, 2010-09-14 (Released:2017-06-19)

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This paper deals with theoretical stability analysis of an active feedback control of web flutter which occurs to the web with both ends fixed and tensioned. In this paper, a non-contact active feedback control method of web flutter by using movable plates set at inlet or outlet of the passage are developed and its analytical model is constructed. The equations of motion of the flexible sheet coupled with the fluid flow controlled by the movable plates are obtained. The characteristic equation of the system is derived as a function of the flow velocity in the narrow gap. As a result, it is shown that the web flutter occurs to the web with increasing the flow velocity, and is effectively suppressed by the proposed non-contact flow control devices and active feedback control method. Furthermore, calculation results are verified by the experiments.

著者

細谷 直人 山川 勝史 松野 謙一

出版者

一般社団法人 日本機械学会

雑誌

流体工学部門講演会講演論文集 2013 (ISSN:24242896)

巻号頁・発行日

pp._G0401-01_-_G0401-02_, 2013-11-09 (Released:2017-06-19)

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The most difficult way to prevent infection among some infection routes is viral droplet nuclei transmission. Droplet nuclei are generated during coughing and sneezing, and suspend for a long time. Hence, specifying its infection route is important issue. The behavior of the droplets is governed by the physical principles. In addition, environmental factors, such as temperature, relative humidity and droplet size, also affect their dispersion and determining the survival. Thus, in this paper, first airflow in the crowded train was analyzed by using CFD.

著者

亀本 喬司

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.75, no.760, pp.2349-2351, 2009-12-25 (Released:2017-06-09)

参考文献数

2

著者

金 連姫 井岡 誠司 久保 司郎

出版者

一般社団法人 日本機械学会

雑誌

関西支部講演会講演論文集 2010.85 (ISSN:24242756)

巻号頁・発行日

pp._3-23_, 2010-03-16 (Released:2017-06-19)

著者

汐月 資純 久保 司郎 楠部 寛和

出版者

一般社団法人 日本機械学会

雑誌

計算力学講演会講演論文集 2002.15 (ISSN:24242799)

巻号頁・発行日

pp.393-394, 2002-10-30 (Released:2017-06-19)

著者

小林 哲治

出版者

一般社団法人 日本機械学会

雑誌

年次大会

巻号頁・発行日

vol.2019, 2019

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<p>Recently the hardware & software technology is improved, many kinds of technologies are developed and adopted to NDT. Especially, in oversea country, the robotics technology is used positively for NDT work. The reason why these technologies are used in oversea is the convenience at first. The advantage of using robotics technology is that it can get the reliable inspection data, reduce outage time & costs for the project. And using robotics technology, it can access the location where an engineer cannot access with safety, for example, Confined spaces (Tank inside), Elevated pipes (pipes at the production facility). Additionally, other main reason is the manpower. Same as recent Japanese industrial market, the lack of manpower is big problem in oversea country. And more, the labor accident during the work at confined spaces, height location and hazardous environment is critical issue same as Japan. Although robotics technology is not perfect, the usage of robotics technology can solve many problems in the present industry. The following is example which the robotics technology is used for NDT work to do the plant maintenance.</p>

著者

國行 一郎

出版者

一般社団法人 日本機械学会

雑誌

機械學會誌 (ISSN:24331546)

巻号頁・発行日

vol.37, no.Suppl, pp.138-145, 1934-08-06 (Released:2017-08-01)

著者

寺島 修 伊澤 精一郎 稲澤 歩 福西 祐

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:18848346)

巻号頁・発行日

vol.77, no.773, pp.56-65, 2011 (Released:2011-01-25)

参考文献数

19

被引用文献数

4 2

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The streamwise interface of an isolated turbulent region in a laminar flat plate boundary layer is investigated by performing a wind tunnel experiment. In the experiment, bimorph-type piezoceramic actuators are used to generate a trapezoidal-shaped turbulent region that has a wide interface in the spanwise direction. With the use of the piezoceramic actuators, the interference of the spanwise interface with the streamwise interface of the turbulent region is eliminated. Therefore, the streamwise interface can be considered as an independent interface. The experimental results show that the rms value of the velocity fluctuation and the turbulent fluctuation rapidly changes at the leading edge of the turbulent region. On the other hand, the rms value of the velocity fluctuation remains high after the turbulent fluctuation disappears at the trailing edge of the turbulent region. It is also shown that the traveling speed of the trailing edge of the turbulent region is faster than the ensemble-averaged streamwise velocity at the trailing edge of the turbulent region near the wall (η≤1.3). In addition, the velocity profile at the trailing edge of the turbulent region indicates the existence of the acceleration of the turbulent fluid near the wall. From the above results, it is found that the inverse transition occurs at the trailing edge of the turbulent region near the wall due to the acceleration of the turbulent fluid.

著者

佐藤 理 岩井 裕 吉田 英生

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.80, no.820, pp.TEP0360, 2014 (Released:2014-12-25)

参考文献数

9

被引用文献数

4 2

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The purpose of this study is to clarify the effect of a component for high-pressure water separation, which is included in the air conditioning system of the general commercial aircrafts, on the air-cycle operation (reverse Brayton cycle); the high-pressure water separation consists of water separator and two heat exchangers called reheater and condenser, respectively. This paper briefly describes the typical system configuration of the air-cycle refrigeration progressed with evolutions in turbofan engine. Since nowadays, 4-Wheel air-cycle has been a trend on the aircraft air conditioning system, this paper theoretically shows its advantage on the basis of the thermodynamic cycle study. In the following chapters, an analysis was conducted on the interaction between a reheater and a condenser when each heat transfer performance changes from the baseline operating point. Also, the comparative study was made on the system performances by the 3-wheel and 4-wheel air-cycle. In addition, this paper describes how the heat transfer performance is designed for the reheater and the condenser under the system requirements for the entire air conditioning system.

著者

竹内 和也 松島 紀佐 金崎 雅博 楠瀬 一洋

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.81, no.827, pp.15-00037, 2015 (Released:2015-07-25)

参考文献数

9

被引用文献数

3 3

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To systematically investigate the aerodynamic characteristics of wings with 30, 45 and 60 degree swept-back angles, and different taper ratios, Navier-Stokes (N-S) simulations for flows over a wing have been conducted. The Mach numbers of the flows range from 0.8 to 2.8. The planforms of wings are in various shapes whose half span aspect ratios are identically fixed in 2.0. The simulation and investigation has revealed new knowledge on the relation between swept-back angles and aerodynamic characteristics of a wing in a supersonic flow. As the aerodynamic characteristics, drag coefficient CD variation is primarily observed along flow Mach number increase. Results of N-S simulations show a realistic profile of the variation which is substantially different from that by the thin-wing theory commonly printed in a textbook. Moreover, the simulation results indicate not only the swept-back angle of a leading edge but also that of a trailing edge take important role on aerodynamics of a wing. Finely, the effect of drag coefficients induced by lift is analyzed using simulation results. It is found that the induced drag in realistic supersonic flows can be treated by the thin-wing theory if three-dimensionality is properly evaluated.

著者

齋藤 彰 久能 友宏

出版者

一般社団法人 日本機械学会

雑誌

Dynamics & Design Conference 2019 (ISSN:24242993)

巻号頁・発行日

pp.351, 2019 (Released:2020-02-25)

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In this paper, applicability of Dynamic Mode Decomposition (DMD) to the extraction of modal properties of linear mechanical systems from their time-domain dynamic responses, i.e., experimental modal analysis is discussed. Of particular interest is its capability to extract modal parameters, i.e., natural frequencies, damping ratios and mode shapes, from measured time histories of displacement of discrete and distributed mechanical systems. First, theoretical background of DMD is briefly reviewed from the viewpoint of structural dynamics. It is shown that the modal parameters can be extracted from the DMD eigenvalues and the associated eigenvectors. The DMD is then applied to analytical solutions of transient response of discrete mass-spring-damper mechanical systems to discuss the applicability of the DMD to extract the modal parameters from the transient response. Furthermore, the effects of measurement errors on the identified modal parameters are discussed. With relatively large measurement errors, it is shown that DMD produces erroneous results especially for the damping ratios. Finally, DMD is applied to experimentally-obtained impulse response of displacement field of a cantilevered beam with many measurement points, and its modal parameters are extracted. It is shown that the modal parameters extracted by DMD are as accurate as the ones obtained by the existing modal parameter extraction method.

著者

里深 信行

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.72, no.718, pp.1385-1387, 2006-06-25 (Released:2011-03-03)

著者

前川 博

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.72, no.724, pp.2845-2850, 2006-12-25 (Released:2011-03-03)

参考文献数

20

著者

草深 あやね 小林 裕央 三木 豪 桑田 真澄 工藤 和俊 中澤 公孝 若尾 真治

出版者

一般社団法人 日本機械学会

雑誌

シンポジウム: スポーツ・アンド・ヒューマン・ダイナミクス講演論文集 2018 (ISSN:24329509)

巻号頁・発行日

pp.A-32, 2018 (Released:2019-05-25)

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The purpose of this study was to verify the precision of different simulation methods to extrapolate vertical pitch location with the use of some dynamic parameters at ball release measured by TrackMan, and to determine dynamic parameters to predict pitch location. Ball trajectory was calculated by the equation of motion with three different numerical analysis methods (Euler, Runge-Kutta, Dormand Prince) and the vertical pitch location was compared with the measured values. The total number of pitches was 137 pitches. Dormand Prince method showed the smallest errors (5.8 ± 1.4 cm) compared with Euler (6.8 ± 1.4 cm) and Runge-Kutta (6.7 ± 1.4 cm) methods, indicating Dormand Prince was the highest precision method to extrapolate pitch location, but all methods could extrapolate it below the size of ball. Simulation with Dormand Prince method and multiple regression analysis revealed that elevation pitching angle and ball velocity more predicted vertical pitch location rather than other parameters. Furthermore, regression equation structured by these parameters could predict the pitch location with error by less than 10.0 cm (9.5 cm). These results indicate that the elevation pitching angle and ball velocity, i.e. velocity vector of ball, affected the determination of pitching location.

著者

村井 聡紀 土屋 茉由 穂苅 真樹

出版者

一般社団法人 日本機械学会

雑誌

年次大会 2013 (ISSN:24242667)

巻号頁・発行日

pp._J231011-1-_J231011-5, 2013-09-08 (Released:2017-06-19)

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In general, bat swing analysis of baseball has adopted an optical motion capture system. It is possible to perform advanced operating analysis, but the system is not practical for large-scale, high cost and labor-consuming measurement. In this study, the trunk rotation movement in baseball bat swing was measured using a three-dimensional gyro sensor. Gyro sensor attached to the shoulder and waist, to measure the angular velocity of the vertical axis of the body. It was possible to show a rotation movement of the trunk during the bat swing similar to the DLT method. There was no significant correlation between the angular velocity of the trunk and swing speed. There was a significant positive correlation between the maximum angular velocity of the waist and maximum angular velocity of the shoulder (r = 0.66). As a result, it was to clarify the relationship of the swing speed and trunk rotation movement.

著者

岡田 正次

出版者

一般社団法人 日本機械学会

雑誌

機械學會誌 (ISSN:24331546)

巻号頁・発行日

vol.41, no.250, pp.73, 1938-02-01 (Released:2017-08-01)