著者
清水 創太
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.73, no.731, pp.2095-2100, 2007-07-25
被引用文献数
4

This paper proposes a model of wide-angle spase-variant image that provides a guide for designing fovea sensor. First, Advanced Wide-Angle Foveated(AdWAF) model is formulized taking all-purpose use into account. This proposed model uses both linear coordinates and logarithmic coordinates in both planar projection and spherical projection. Thus, this model divides its 120-degree wide-angle field of view into 4 areas, such that it can represent images by various types of lens, flexibly. The first simulation compares with other lens models, in terms of image height and resolution. The result shows the AdWAF model can reduce image data by 13.5 percent, comparing with a log-polar lens model, when both have the same resolution in the fovea area. The second simulation compares with other foveation models used for the existing wide-angle foveated lens, logpolar chip and vision system. The third simulation estimates scale-invariant property by comparing with the Kuniyoshi's lens and the log-polar lens. The AdWAF model gives its planar logarithmic part complete scale-invariant property, while the Kuniyoshi's lens has about 7.6-percent error at most in its spherical logarithmic part. Moreover, the AdWAF image is extracted from an input image by wide-angle foveated(WAF) lens, based on the proposed model.
著者
山田 敦 青石 義人 内藤 禎章 吉原 誠 後藤 泰弘 小野寺 隆
出版者
一般社団法人日本機械学会
雑誌
昇降機・遊戯施設等の最近の技術と進歩技術講演会講演論文集 : Elevator, Escalator and Amusement Rides Conference
巻号頁・発行日
vol.2002, pp.25-28, 2002-01-23

According to multistory building increase, the number of elevators tends to increase. In this case, also the space needed for hoistway or machine room increases, and as a result the effective floor space of the building decreases. In a common elevator (single deck elevator), there is one machine for one cab, but in a double deck elevator there is only one machine for two cabs, therefor the space needed for transportation can be reduced. However, in recent building design, there are a lot of cases that the height between floor and floor is not equal. In actual double deck elevator, the upper car and the lower car are fixed to car frame and it cannot cope with the difference between each floor. We have developed a Super Double Deck Elevator, in which upper cab and lower cab can move coping with the difference between each floor.
著者
高木 周 松本 洋一郎 黄 華雄
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.61, no.586, pp.1976-1983, 1995-06-25
被引用文献数
10

A numerical method is developed to simulate the unsteady axisymmetric flow with a free surface. The method is based on a finite-volume solution of the equations on an orthogonal curvilinear oordinate system. A new iteration technique is used for the boundary condition of the free surface to stabilize the solution. The method is applied to simulate an unsteady motion of a single deformed bubble rising through a quiescent liquid. The numerical results show quantitatively good agreement with those of experiments and calculations of others. In the present study, the transitional phenomena of the initially spherical bubble in reaching the steady state are investigated. It is known experimentally that the rising bubble begins to show an unsteady three-dimensional (spiral or zigzag) motion beyond certain critical Reynolds and Weber numbers. Our numerical results of the axisymmetric flow show unsteady shape oscillations in the parameter range of the three-dimensional motions.
著者
浜口 和洋 高橋 真太郎 宮部 英也
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.48, no.435, pp.p2207-2216, 1982-11
被引用文献数
3

スターリング機関再生器のマトリックス材としてメッシュ数の大きい金額を多数枚積層したものが使用されているが, その流動損失に関する研究は少ない. 本研究では, 10から300メッシュまでの広い範囲の金網を積層したマトリックスの定常流および非定常流における流動損失を調べた. おのおのの場合において, 金網の幾何学的形状を知ることにより, 任意の金網の摩擦係数をレイノルズ数の関数として与える実験式が得られた.
著者
林 達規 森 孝男
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.2008, no.1, pp.91-92, 2008-08-02

The role of a pressure sensor is to display pressure definitely for at least 2000 hours. However, a residual strain after reloading occurs in the diaphragm using in the high-pressure. This study involved a finite element analysis of the sensor. As the result of the analysis, the residual strain was improved by making the thickness of diaphragm thicker. However, it is thought that the sensitivity of a sensor may become poor. Therefore, it is important to reduce the force by optimizing the structure. Measurement accuracy and durability is required of high-pressure equipment. Therefore, it is important with the diaphragm type pressure sensor to examine the influence that shape and the size of diaphragm exert on the measurement accuracy and durability. As a first step, the diaphragm size was clarified. A finite element method (FEM) based on the experimental design was used. And, to optimize the size of the diaphragm, each part was examined by clarifying the stress and warp distributions.
著者
瀬尾 和哉 渡部 勲 太田 香織 村上 正秀
出版者
一般社団法人日本機械学会
雑誌
ジョイント・シンポジウム講演論文集 : スポーツ工学シンポジウム : シンポジウム:ヒューマン・ダイナミックス : symposium on sports engineering : symposium on human dynamics
巻号頁・発行日
vol.2001, pp.136-140, 2001-11-07

This paper describes the aerodynamic forces acting on the ski jumper during the landing phase as well as the free flight phase. The full size model was employed to measure the lift area, the drag area and the moment volume, which was mounted in a 3-meter low speed wind tunnel. The ground effect plate was set in the test section of the wind tunnel. The clearance between the plate and the center of mass of the body-ski combination was about 1 m. It was found that the difference between the lift area with the ground effect plate and that without the ground effect plate increased with the ski-opening angle, though difference of both lift areas was independent of the angle of attack. The difference of both drag areas was small. The flight distance was estimated about 146 m, which is 6 m longer by taking account of the ground effect.
著者
藤沢 延行 Adrian Ronald J.
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.63, no.607, pp.818-823, 1997-03-25
被引用文献数
8

A new calibration technique of liquid crystal thermometry has been introduced to the quantitative measurement of temperature in a thermal fluid and applied to the study of turbulent thermal convection. The present calibration technique improves the accuracy of temperature measurement in comparison with the classical calibration technique with hue. Three-dimensional temperature measurement of turbulent thermal convection over a horizontal smooth surface is carried out at a flux Rayleigh number of 3×10^9 by scanning a light sheet normal to the image plane and capturing a number of sequential visualized images. The spatial temperature distributions of thermal plumes over a horizontal surface are demonstrated by the reconstruction of isothermal contour surfaces and various cross-sectional views of the plumes. These results indicate the presence of a polygonal cell structure close to the surface and the generation of plumes at the intersections of high-temperature lines.
著者
清水 徹 横川 明 鈴木 基光 中村 育雄
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.51, no.469, pp.2908-2915, 1985-09-25
被引用文献数
1

種種の乱れ発生要素を入り口に設けたく形断面流路における繊維懸濁液流れの濃度むらを比較的高い濃度にわたって測定し,その管軸方向への分布や平均濃度および平均流速に対する依存症について検討した.この結果,流れの乱れによる濃度むらの減少には限界値が存在すること,また十分に発達した流れ場における繊維懸濁液の濃度むらは非ニュートン流体の広義のレイノルズ数で整理できることが明らかになった.
著者
篠山 鋭一 斉藤 敬三
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.47, no.421, pp.1891-1899, 1981-09-25

比較的光化学スモッグが発生しやすい条件を基本にとり, この条件から各種因子を変えてスモッグチャンバによる光化学エアロゾルの生成実験を行うことによりこの条件における各種因子の影響を調べた. HCはエアロゾル生成に正負両面の影響を持ちその影響は種類により大きく異なること, NO_xは負の影響を持つと考えられること, SO_2は正の影響を持つこと, 湿度は大きな正の影響を持つことなどが解明された.
著者
古屋 泰文 岡崎 禎子 上野 孝史 Chung Lee Gyun Spearing Mark Hagood N.
出版者
一般社団法人日本機械学会
雑誌
機械材料・材料加工技術講演会講演論文集
巻号頁・発行日
vol.2004, no.12, pp.19-20, 2004-11-05

The possibility to detect the phase transformation of stress-induced martensite in ferromagnetic shape memory alloy Fe-30.2at%Pd thin foil was investigated by using Barkhausen noise (BHN) method. Stress-induced martensite twin was observed by laser microscope above loading stress of 25 MPa. BHN caused by grain boundaries appears in the lower frequency range and BHN by martensite twin in the higher frequency range. The envelope of the BHN voltage as a function of time of magnetization shows a peak due to austenite phase at weak magnetic field. The BHN envelope due to martensite twins creates additional two peaks at intermediate magnetic field. BHN method turns out to be a powerful technique for non-destructive evaluation of the phase transformation of ferromagnetic shape memory alloy.
著者
陶 キン 萩原 一郎 呉 卓〓
出版者
一般社団法人日本機械学会
雑誌
日本機械学会関東支部総会講演会講演論文集
巻号頁・発行日
vol.2004, no.10, pp.195-196, 2004-03-03

Recently origami technique is being applied to many industrial products. For example, a new kind of beverage container made by origami structure has been introduced and proved that is can be easily crushed after usage. However, since this structure is only designed from origami theory, its function especially external appearance does not meet human requirements very well. Thus, in this research, starting from the view of industrial design theory, the structure of beverage container is redesigned by the technology of subdivision method. Furthermore, rapid prototyping system is used to produce the new model. Study results indicate that the beverage container got in this study has a much better performance.
著者
三浦 登
出版者
一般社団法人日本機械学会
雑誌
日本機械学会関東支部総会講演会講演論文集
巻号頁・発行日
vol.2004, no.10, pp.197-198, 2004-03-03

The structure model made of wire can express a beam, a truss, a Rahmem construction, a joint component, a shear panel, various kinds of joint, a link, etc. If model rules are relaxed and the scale factor of length and the scale factor of flexural rigidity are chosen independently, the wire model which can be handled with fingers can visualize the deformation mode of real structure, and can express the rigidity. In this case, the model rules and the magnification of a deformation are explained. This wire model is regarded as the physical feeling-media which connect the real world of structure and the virtual world of CAE, and is a simulation tool and a thinking tool.