著者

竹田 憲生

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. A編 = Transactions of the Japan Society of Mechanical Engineers. A (ISSN:03875008)

巻号頁・発行日

vol.73, no.733, pp.105-112, 2007-09-25

参考文献数

12

被引用文献数

1 3

---

This paper verifies the response surfaces of artificial neural networks (NN) learned by using a method based on Bayesian inference. Mackay showed that the Bayesian method due to Gull and Skilling can be applied to regularization for NN. However, generalization ability has not been verified sufficiently for the NN response surface regularized by using the Bayesian method. If the NN response surface has good generalization ability, it can be used in the optimization process of response surface methodology (RSM) NN therefore was learned by using the Bayesian method to investigate generalization ability. We tried three rules for updating the regularizing constants in an objective function minimized during NN learning. All of the update rules were derived from the Bayesian method. As a result, the response surface of NN had good generalization ability, with the exception of one update rule. The poor update rule failed to determine the regularizing constants. This tendency for the update rules was recognized regardless of response surface geometry. After we selected a superior update rule, the NN response surface by using the Bayesian method was applied to an optimization problem. The response surface didn't fit noises included in teacher data, and consequently, it was effectively used to reach a solution. Finally, we concluded that the NN learned by using the Bayesian method can be used as the response surface in the process of RSM.

著者

尾田 十八 坂本 二郎 坂野 憲一

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. A編 = Transactions of the Japan Society of Mechanical Engineers. A (ISSN:03875008)

巻号頁・発行日

vol.71, no.701, pp.89-94, 2005-01-25

参考文献数

6

被引用文献数

2

---

A woodpecker strikes its beak toward a tree repeatedly. But, the damage of brain or the brain concussion doesn't occur by this action. Human cannot strike strongly the head without the damage of a brain. Therefore, It is predicted that the brain of a woodpecker is protected from the shock by some methods and that the woodpecker has the original mechanism to absorb a shock. In this study, the endoskeltal structure, especially head part structure of woodpecker is dissected and the impact-proof system is analyzed by FEM and model experiment. From the results, it is obvious that the woodpecker has the original impact-proof system as the unique states of hyoid bone, skull, tissue and brain. Moreover it is considered that woodpecker has the advanced impact-proof system relating with not only the head part but also with the whole body.

著者

松原 雅昭 伊澤 悟 平尾 典盟 毒島 康二 小山 哲 町田 康治 川田 大介 坂本 賢治 根津 紀久雄

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. A編 (ISSN:03875008)

巻号頁・発行日

vol.67, no.659, pp.1218-1222, 2001-07-25

参考文献数

11

被引用文献数

1 1

---

The authors developed a new testing equipment for studying statically indeterminate fracture mechanics. Its development purpose is to clarify load history-dependency of the collapse load. The equipment has two actuators orthogonalized. The horizontal actuator applies the axial force and the perpendicular one does the bending moment. In the experiment for examining the effect of load hysteresis on the collapse load, both actuators can keep the preceding load to the constant load value, until axial force and bending load reach the theory collapse point. The actuators can apply the following load under the displacement control in the experiment. The performance of the equipment was confirmed by demonstration tests using single-edge notched specimens of SUS 304 steel. The experimental result clarified load historydependency on collapse load in SUS 304 single-edge notched member subjected to combined tension and bending.

著者

井上 裕嗣 岸本 喜久雄 中西 智明 渋谷 壽一

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 A編 (ISSN:03875008)

巻号頁・発行日

vol.61, no.581, pp.153-160, 1995-01-25 (Released:2008-02-21)

参考文献数

17

被引用文献数

5 6

---

The wavelet transform is applied to time-frequency analysis of dispersive stress waves. The Gabor function is adopted as the analyzing wavelet. The magnitude of the wavelet transform of wave data takes its maximum value at the time when the stress wave reaches the observation point with its group velocity at each frequency. An experiment on the flexural wave in a beam shows that the dispersion relation for the group velocity can be accurately identified by the wavelet transform of measured data. In addition, the application of the wavelet transform to ultrasonic testing of a polymer alloy shows that changes in velocity and attenuation coefficient due to mechanical damaging can be evaluated at each frequency. These results suggests that the wavelet transform has potential ability to present more detailed evaluation of material damages.

著者

金 敏健 山田 邦博 国尾 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 A編 (ISSN:03875008)

巻号頁・発行日

vol.51, no.465, pp.1304-1310, 1985

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共析鋼に脱炭処理を施すことによりフェライトが種々混在する試験片を作製し, 耐久限度の大小に及ぼす限界停留き裂寸法l<SUB>c</SUB>とフェライト体積分率V<SUB>fF</SUB>の関係を調べるとともに, セメンタイトラメラ間隔の変化が耐久限度に及ぼす影響についても検討を加え, 以下に述べる結論を得た. 耐久限度の大小は, l<SUB>c</SUB>がV<SUB>fF</SUB>の減少とともに減少するという現象を通じてV<SUB>fF</SUB>と密接に関連する. また, 耐久限度σ<SUB>woとl<SUB>c</SUB>との間にはσ<SUP>m</SUP><SUB><</SUB>wo</SUB>l<SUB>c</SUB>=Cとなる関係が成立する.

著者

尾崎 公一 福田 忠生 西 亮 椎森 康雄 早川 悌二

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 A編 (ISSN:03875008)

巻号頁・発行日

vol.73, no.726, pp.279-284, 2007-02-25 (Released:2011-03-02)

参考文献数

4

被引用文献数

1

---

In order to investigate the flow of molten metal in a cavity of a die, experimental simulation was carried out by using water flow model. The experimental cavity was constructed of a backward step configuration for test zone, in which flow behavior and air exhaust process from the cavity were investigated. With rib material installed down the step, its effect on air exhaust promotion was examined for various flow velocities. The main results obtained are as follows : Air exhaust from the cavity is remarkably promoted by installation of rib because the strong turbulence around the rejoining potion of two different flows, which are separated by the rib at the upstream, broke rapidly the trapped air into small bubbles. The time taken to complete air exhaust process is in inverse proportion to the flow velocity in the high velocity region, while it is proportion to the flow velocity to the -2.27th power in the low velocity region.

著者

秋庭 義明 木村 英彦 鶴 尋貴 中村 亜有子

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 A編 (ISSN:03875008)

巻号頁・発行日

vol.74, no.742, pp.879-884, 2008-06-25 (Released:2011-03-02)

参考文献数

18

被引用文献数

1

---

Fatigue test system for thin sheets was constructed using an ultrasonic fatigue testing machine. Specimens were fixed at the location where the displacement amplitude became the maximum. The specimen was fatigued under full-reverse bending. Displacement at a fixed edge of the specimen and the deflection of the specimen were measured with a laser displacement gage during fatigue tests. Modal analysis was carried out to determine the dimensions of the specimen and to calculate the applied stress on the basis of the flexural displacement amplitude. The maximum stress was observed on the free side edge near the fixed edge. Two kinds of martensitic stainless steel sheets, SUS301-CSPH and SUS632J1-CSP, were fatigued with the fatigue test system. The thickness of the specimen was 83 and 106μm, respectively. The 3rd vibration mode was selected for fatigue tests. The fatigue cracks initiated from the free side edge of the specimen. For the case of shorter fatigue life, fatigue strength for both stainless steels were almost identical. On the other hand, for longer fatigue life, fatigue strength of SUS632J1 is higher than that of SUS301.

著者

越智 保雄 佐々木 茂美

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 A編 (ISSN:03875008)

巻号頁・発行日

vol.47, no.417, pp.483-491, 1981

被引用文献数

1 2

---

平滑丸棒試験片を用いて応力制御の引張圧縮疲労試験を行なった. 初期段階のΔεpやH<SUB>V</SUB>の増加は転移密度の増加に依存している. この段階は局部的な疲労降伏域が試験片全体に広がる過程である. 中期段階は繰返しによる動的快復の過程であって, 自由転移の移動を規制するセル構造(σ<SUB>a</SUB>大)やループパッチ組織(σ<SUB>a</SUB>小)間の大きさの減少がΔεpの減少を支配している. 初期から中期段階へのせん移は, 疲労すべり帯がなだれ的に発生するためである.

著者

佐藤 裕久 菊池 亘 鈴木 英

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.63, no.616, pp.2618-2623, 1997-12-25

被引用文献数

7 3

---

An unsteady-wave-sensing-system (UWSS) is developed for evaluating the wave propagation characteristics of polymethyl methacrylate (PMMA) for loading-reloading-unloading waves using plate-impact experiments and three PVDF gauges. By applying the UWSS, stress, particle-velocity, strain and two kinds of phase velocities at one location in the PMMA are determined as functions of time. The phase velocities U^σ associated with the stress profiles are generally different from the other phase velocities U^υ associated with the particle-velocity profiles. From loading to reloading are transitions very near from the Hugoniot in the stress-strain plane, but from reloading to unloading are transitions upward off the Hugoniot. In the region of our experimental stress, PMMA does not behave as liquid and the Hugoniot of PMMA is not effective for the loading-history-characteristics.

著者

清水 理能 五嶋 孝仁 内山 隆嗣 石原 外美

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 A編 (ISSN:03875008)

巻号頁・発行日

vol.71, no.711, pp.1546-1553, 2005-11-25 (Released:2011-03-02)

参考文献数

16

---

This paper considered three dimensional internal inclined crack growth behaviors due to repeated rolling thermoelastic contact. In this analysis, crack is modeled as an internal inclined planar crack in a three dimensional half-space. Rolling contact is simulated as a long and narrow distributed load with both normal and shear components moving with constant velocity. In comparing the shearing force with the frictional force of crack surface, the phenomenon of stick and slip were considered. At first, stress intensity factors along the crack contour are analyzed using high carbon chromium bearing steels. Next, numerial results of crack growth contours are given based on a modified Paris power low. And fatigue life is estimated by maximum crack growth. The shapes of crack contour and fatigue life are calculated under various conditions, which change sliding ratio, frictional coefficient, angle of inclined crack and friction coefficient of crack surface. As results, when the friction of crack surface is large, the crack progresses greatly in the direction at no friction of crack.

著者

鈴木 新一 森田 康之 坂上 賢一

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 A編 (ISSN:03875008)

巻号頁・発行日

vol.67, no.655, pp.432-439, 2001-03-25 (Released:2008-02-21)

参考文献数

24

被引用文献数

3 4

---

High-speed holographic microscopy is applied to take successive microscopic photographs of a fast propagating crack at bifurcation. The crack speed is about 650 m/s. From the photographs, crack opening displacements (CODs) of the mother crack and two bifurcated branches are measured along the crack. A specimen with a notch is also made, where the notch has the bifurcated notch tip same as the bifurcated fast propagating crack. Opening displacement of the notch is measured by Moire interferometry under static loading condition. The measurement results show that the opening displacements of both the mother crack of the bifurcated fast propagating crack and the mother notch of the bifurcated notch are proportional to square root of the distance r from the crack or the notch tip. The opening displacements of the two bifurcated branches of the notch are also proportional to √(r). But the CODs of the bifurcated branches of the fast propagating crack are not always proportional to √(r).

著者

坂 真澄 巨 陽

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 A編 (ISSN:03875008)

巻号頁・発行日

vol.65, no.639, pp.2193-2198, 1999-11-25 (Released:2008-02-21)

参考文献数

24

著者

宇賀地 弘和 奥 達雄 石山 新太郎 衛藤 基邦

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.62, no.593, pp.10-17, 1996-01-25

参考文献数

9

---

Since carbon fiber reinforced carbon composite (C/C composite) materials have good mechanical properties at high temperature and low radioactivity under irradiated conditions, they have been used as the plasma-facing components in fusion facilities. Efficient utilization of these mechanical properties will lead to the use of c/c composite materials, these materials are expected for use as control rods for gas-cooled rectors and irradiating capsules. In the case of using c/c composite materials as the structural components, it is very important to evaluate the mechnical and thermal properties as well as fracture behavior. For structural components used in a reactor core, it is necessary to evaluate neutron-irradiation effects on these materials. However evaluation of these effects has been difficult, thus data on irradiated c/c composite materials are lacking. In this study, three kinds of c/c composite (CC-312, CX2002U and MCI) made of different fiber materials were irradiated under the condition of maximum neutron fluence of 2×10^<25> n/m^2 and maximum irradiating temperature of 1200℃, and the relationship between change of mechanical properties due to irradiation and the constitution of c/c composite materials was evaluated. In the case of CC-312 made of PAN fiber, Young's modulus changed slightly and bending strength after irradiation. In the case of CX2002U made of rayon fiber, Young's modulus and bending strength increased after irradiation. In the case of MCI made of pitch fiber, Young's modulus increased after irradiation, but bending strength decreased slightly after irradiation. These results enable the elucidation of the relationship between properties of fiber meterials and irradiation effect on c/c composite materials.

著者

山崎 友裕 西野 博満 片山 大希

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.76, no.762, pp.145-150, 2010-02-25

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Electromagnetic acoustic transducer (EMAT) is applied to resin cure monitoring in manufacturing process of fiber reinforced plastic (FRP) by resin transfer molding (RTM) method. The RTM is suitable for fabrication of FRP products of three-dimensional complex shape. In order to reduce the cost by minimizing the cycle time, cure monitoring is required. Authors have already ensured that the EMAT can detect the resin flow front in RTM process by monitoring the change in reflection coefficient at mold surface due to resin impregnation. The reflection factor is also affected by the resin viscosity. In this study, during the curing process, we measure the attenuation coefficient of standing wave introduced in the mold. Results are compared with impedance of dielectric sensor located inside the mold, showing that the degree of cure can be evaluated by EMAT at outer surface of the mold.

著者

座古 勝 倉敷 哲生

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.62, no.594, pp.583-588, 1996-02-25

被引用文献数

1

---

When an explosion occurs in chemical plants, the explosion pressure leads to collapse of pipes and equipment. Even if pipes are not destroyed immediately by the explosion pressure, the cumulative damage caused by the sequential explosion pressure will bring about collapse. Therefore, the disaster simulation program, which takes the cumulative damage into consideration, has been developed. In this program, three-dimensional explosion pressure applied to pipes can be calculated, and the equivalent stress acting on the connecting bolts of pipes can be analyzed. The cumulative damage is estimated by use of the obtained stress, Manson-Coffin's rule and Miner's rule. As an example, the cumulative damage over time for pipes in a model plant has been analyzed. As a result, it is shown that the proposed computer program is very useful for reliability evaluation and installation of pipes in chemical plants.

著者

町田 賢司 菊池 正紀 澤 芳昭 Fu-Pen CHIANG

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.60, no.573, pp.1294-1299, 1994-05-25

被引用文献数

7 1

---

Two-dimensional Fourier transform analysis is presented as an advanced method for numerically processing the Young's fringes diffraction pattern from a double-exposure speckle photograph. The fringe spacing and orientation are determined using only one Young's fringes pattern without any other diffraction halo patterns. This algorithm is based on the 2-D FFT of the fringe pattern with 256×256 pixels. Therefore, it has enabled automatic analysis to be performed with noisy and poor fringe patterns. The measurement of deformation field by the laser speckle method can be carried out with higher accuracy, reliability and speed.

著者

平島 健一 杉坂 憲明

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 A編 (ISSN:03875008)

巻号頁・発行日

vol.60, no.575, pp.1557-1563, 1994-07-25 (Released:2008-02-21)

参考文献数

4

被引用文献数

1 5

---

This paper presents a unified analysis of isotropic out-of-plane shear problems containing two circular elantic inclusions and shows the analytical solutions. The applied forces considered in this paper are longitudinal shear stress at infinity, concentrated force, screw dislocation, dipole force, dipole dislocation and distributed forces, at arbitrary positions. The analysis is based on the complex variable method using the Mobius transformations by Honein and Herrman. Several numerical examples are given by graphical representations.

著者

西谷 弘信 尾田 安司

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.46, no.407, pp.745-755, 1980-07-25

被引用文献数

1 10

---

半無限板の直線縁またはその付近に存在するき裂同志またはき裂と切欠きの干渉効果を体積力法によって計算した. 取扱った問題は, (a)遠方で引張りを受ける半無限板中の, (i)V形切欠き底のき裂, (ii)2個の縁き裂, (iii)先行き裂を伴う縁き裂, (iv)先端にだ円孔を有する縁き裂, および(b)き裂面に多項式で表される分布荷重を受ける縁き裂である. 最後の問題は切欠き底のき裂, 複数個の縁き裂などの応力拡大係数を近似的に求めるのに有効である.

著者

塩澤 和章 小林 弘和 寺田 正夫 松井 明

出版者

社団法人日本機械学会

雑誌

日本機械学会論文集. A編 (ISSN:03875008)

巻号頁・発行日

vol.67, no.662, pp.1639-1646, 2001-10-25

参考文献数

12

被引用文献数

2 2 1

---

As a study in a series to investigate the effect of anodized coating on fatigue strength of aluminum alloys, repeated tensile fatigue test was conducted in laboratory air and at room temperature under the stress ratio of 0.01 using smooth plate specimen of A2014-T6 and A6151-T6 with anodized film thickness of 3&mu;m. Fatigue strength of the anodized specimens decreased by 20-30% as compared with those of uncoated one. Decrease of fatigue strength depended on static strength of the tested materials. The fracture of anodized coating film occurred at the critical strain formed by the accumulation of plastic deformation of substrate metal at an early stage of repeated tensile fatigue process and crack was induced in the substrate at the flaw of the anodized film. It was recognized that fatigue life of anodized specimens was quantitatively evaluated by the consideration of cyclic stress-strain response and strain-life fatigue behavior.

著者

佐脇 豊 伏谷 裕士 徳田 正孝 八木 一夫 稲葉 忠司 関岡 清次 中野 赳

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 A編 (ISSN:03875008)

巻号頁・発行日

vol.63, no.611, pp.1533-1538, 1997-07-25 (Released:2008-02-21)

参考文献数

19

被引用文献数

2 3 8

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Stress distributions in a canine left ventricular wall are simulated during one cardiac cycle by employing 3-dimensional finite element models developed in order to estimate the functions of the left ventricle. The appropriateness of the numerical simulator is examined by comparing the pressure volume relationships of the left ventricle computed by the present system with those obtained by the corresponding canine experiments. The initial geometry of the left ventricle is assumed to be a prolate spheroid in order to facilitate easy estimation of the complex computed numerical results. It is recognized that the distributions of the wall stress, e.g., the circumferential stress, near the equatorial surface are quite different from those of the thick cylinder subjected to the internal pressure and that the magnitudes and the directions of the principal stresses are closely related to both the contractility and the orientation of the myocardial muscle fiber.