JaLCDOI 10.18926/19608
フルテキストURL Mem_Fac_Eng_OU_33_1_19.pdf
著者 鷲尾 誠一| 高橋 智| 井元 智可至| 吉田 篤正|
抄録 The present paper deals with measurements of the diffusion coefficients as well as the saturated solubilities of single component gases such as N(2), O(2) and CO(2) to a mineral oil. The method to determine the diffusivity is based upon measuring the pressure changes caused by the one-dimensional diffusion between the gas and the oil enclosed in an airtight container. For N(2) and O(2) the profiles of the measured pressure changes agree well with those predicted by diffusion theory, whereas that is not the case with CO(2). Although the reason why CO(2) does not seem to obey diffusion theory has yet to be studied, it may suggest the possibility that the diffusion coefficient varies with the pressure, considering that the range of pressure change in the diffusivity measurement was much obtained by this method fell within ±30% around the average. Moreover the solubility measurements have made clear that Henry's law holds true between the three pure gases and the oils tested, and that O(2) and CO(2) dissolve into the oil approximately two and ten times more, respectively, than N(2).
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1998-11-30
33巻
1号
開始ページ 19
終了ページ 30
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002309030
JaLCDOI 10.18926/19606
フルテキストURL Mem_Fac_Eng_OU_33_1_5.pdf
著者 阿部 武治| Namikoshi Ryuji| Nagayama Noriyuki| Takano Yasuju|
抄録 The influence of the slip between the inclusion and the matrix during the plastic deformation of inhomogeneous material with elliptic inclusions is investigated. The material is assumed to be rigid-plastic. The boundary slip region is modeled by assuming lower yield stress for the thin boundary region than those of the inclusion and the matrix. The rigid-plastic finite element method is used for the numerical calculation under the plane strain condition. The effects of the aspect ratio of the inclusion, the yield stress of the boundary region, and the volume fraction of the inclusion on the deformation mode are studied. The patterns of the strain concentration and the averaged flow stress of the inhomogeneous material are also discussed. The results may be helpful for understanding creep or superplastic deformation of metals with inclusions.
キーワード Plasticity Composite Material Sliding Inclusions Rigid-Plastic Deformation Finite Element Method
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1998-11-30
33巻
1号
開始ページ 5
終了ページ 17
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002309204
JaLCDOI 10.18926/19604
フルテキストURL Mem_Fac_Eng_OU_33_1_1.pdf
著者 榊原 精| Kanadani, Teruto|
抄録 Aging of diolute Al-Ag alloys after quenching from low temperatures were studied mainly by electrical resistometry. Maximum resistivity observed in the aging curve of specimens quenched from high temeperature disappeared when the quenching temperature was lowered to 473 or 453K. When the quenching temperature was lowered further to 423K or lower, however, maximum resistivity reappeared. At the temperature lower than or equal to 423K but higher than the GP zone solvus, the alloys were not homogeneous but had clusters of solute atoms or fluctuation of solute concentration. Inhomogeneous distribution of solute atoms may affect the aging behavior after quenching from that temperature.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1998-11-30
33巻
1号
開始ページ 1
終了ページ 4
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002309092
JaLCDOI 10.18926/19603
フルテキストURL Mem_Fac_Eng_OU_31_2_67.pdf
著者 Li Zhenzi| 大崎 紘一| 梶原 康博|
抄録 In this paper, we propose the price determination method using the parameter of the price elasticity that shows the relation between price and demand. Firstly, the state of the price elasticity is examined under the condition that the relation between price and demand are assumed by the inverse proportional function, the linear function and the quadratic function. Secondly, the profit is estimated for each product by break even point analysis. And the price is determined under the condition that the relation between the demand and price is shown by one of three demand-pridce functions above mentioned.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1997-03-28
31巻
2号
開始ページ 67
終了ページ 72
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002309056
JaLCDOI 10.18926/19601
フルテキストURL Mem_Fac_Eng_OU_31_2_61.pdf
著者 Yamada Mitsuru| 大崎 紘一|
抄録 At present, the two dimensional CAD systems which are used to make drawings go around widely. But in order to use design data at the lower stream of production process, the replacement from the two dimensional CAD systems to the three dimensional CAD systems have started. Accordingly it is dimensional drawings for the three dimensional shapes. And it is also necessary to store them in the three dimensional CAD systems. And in the studying of the machine vision which is often used as "Eyes of robot" , it is being studied the method to recognize the three dimensional objects from the two dimensional image. This is the problem about data exchange, too. Therefore in this report, we propose the method to exchange the plural two dimensional elements of figure from image relations between elements were found from reference of the element coordinates. Next, the three dimensional shapes were reasoned from reference of the knowledge (for corner, etc) prepared beforehand. Then that data were exchanged to the three dimensional CAD data. We report one example about this method.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1997-03-28
31巻
2号
開始ページ 61
終了ページ 65
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002309050
JaLCDOI 10.18926/19599
フルテキストURL Mem_Fac_Eng_OU_31_2_53.pdf
著者 Fujihara Yutaka| 大崎 紘一|
抄録 This paper presents a method using simulated annealing(SA) and genetic algorithm(GA) to solve the plant layout problem in which the layout is evaluated by material handling cost and maintainability. In the former study about facility layout problem, it was either the minimization of the objeective function consisting of transport cost or the maximization of the objective function consisting of closeness rating. In this paper, both transport cost and maintainability were included in the objective function to be minimized. The plant layout problem, this paper proposes the heuristic procedures to obtain a suboptimal layout solution by combining SA with GA. From the simulation by computer, it concluded that the method which SA is combined with GA is more efficient than the method which utilizes SA and GA independently.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1997-03-28
31巻
2号
開始ページ 53
終了ページ 60
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002309131
JaLCDOI 10.18926/19596
フルテキストURL Mem_Fac_Eng_OU_31_2_45.pdf
著者 尾坂 明義| Kobayashi Keizo| 早川 聡| 大槻 主税|
抄録 The thermal expansion coefficient of some bioactive glasses in the system CaO-SiO(2)-B(2)O(3) were adjusted to be similar to that of titanium by controlling the composition. A glass of composition 45CaO・30SiO(2)・25B(2)O(3) was selected among those as the enameling glass. A slurry was prepared by mixing the glass powder and ethanal to be developed on titanium and heated at 740℃ for 30 min. Thus treated specimen was soaked in a simulated body fluid (Kokubo solutiion). FT-IR reflection and thin film X-ray diffraction analyses indicated apatite formation on the glass coating layer within 12 h of soaking in the fluid. Thus titanium could be provided with bioactivity due to the enameling.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1997-03-28
31巻
2号
開始ページ 45
終了ページ 51
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002309181
JaLCDOI 10.18926/19594
フルテキストURL Mem_Fac_Eng_OU_31_2_39.pdf
著者 Imayoshi Naoki| 早川 聡| 大槻 主税| 尾坂 明義|
抄録 Nb(2)O(5)-and Ta(2)O(5)-doped calcium si1icate glasses were soaked for various periods in a simulated body fluid(Kokubo solution) up to 30 days. Apatite formation ability of the surface of these glasses were investigated with thin-film X-ray diffraction and FT-IR reflection spectroscopy. The effects of these additive oxides on the bioactivity of CaO・SiO(2) based glass were discussed. A small amount of Nb(2)O(5) and Ta(2)O(5) suppressed the rate of silica hydrogel layer formation and the apatite formation on the surface of the glasses. The rate of the apatite nucleation on the surface of Nb(2)O(5)-doped calcium silicate glass was slower than that on the surface of Ta(2)O(5)-doped calcium silicate glass. It was concluded that the decrease in the apatite forming ability of calcium silicate glasses by these additive oxides is attributed to the suppression of formation of silica hydrogel layer which plays an important role in apatite nucleation.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1997-03-28
31巻
2号
開始ページ 39
終了ページ 44
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002309151
JaLCDOI 10.18926/19592
フルテキストURL Mem_Fac_Eng_OU_31_2_29.pdf
著者 岡 久雄| 大島 正和|
抄録 Knee replacement arthroplasty is indicated for the patient with advanced knee pain, knee deformation, and knee functional disorder. The aim of this study was to estimate loosening after a knee replacement arthroplasty. Loosening is measured by a frequency response function, and mobility by random vibration. The modal parameters for the knee joint are obtained by applying a modal analysis to the frequency response function. The values decrease as the knee joint prosthesis loosened. These parameters serve as an index for the condition between a thighbone and the prosthesis. The various indexes will greatly clarify the stage of advance in the loosening of knee-joint prostheses.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1997-03-28
31巻
2号
開始ページ 29
終了ページ 37
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002309172
JaLCDOI 10.18926/19591
フルテキストURL Mem_Fac_Eng_OU_31_2_21.pdf
著者 岡 久雄| 中村 貴彦|
抄録 In evaluating the stiffness of skin surface, internal structures such as bone and muscle often affect the measurements. In the present paper, acoustic random vibration is used to estimated the viscoelasticity of a silicone-gel model. This viscoelasticity, which includes two different stiffness strata, is first estimated using a mechanical impedance spectrum, which describes the relation between the depth and viscoelasticity of internal objects. This method is applied to the depth of a silicone-gel tumor model measured by ultrasound imaging and the viscoelasticity of internal gel can be accurately estimated.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1997-03-28
31巻
2号
開始ページ 21
終了ページ 27
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002309105
JaLCDOI 10.18926/19589
フルテキストURL Mem_Fac_Eng_OU_31_2_11.pdf
著者 Ishii Kouta| 竹元 嘉利| 飛田 守孝|
抄録 Fine particles of Ti-V alloy were prepared by means of arc method and were investigated on internal structure and phase transformation using HR-TEM and EDS. Martensite phase was observed in a particle containing comparatively low concentration of V, and ω phase was also found to exist in a nearly 15% V particle. The structure of the ω phase in the fine particle is remarkably expanded in comparison with the bulk sample, and the ω phase is unstable, so that it has disappeared in a few seconds during TEM observation.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1997-03-28
31巻
2号
開始ページ 11
終了ページ 20
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002309004
JaLCDOI 10.18926/19588
フルテキストURL Mem_Fac_Eng_OU_31_2_1.pdf
著者 Arisawa Hideaki| Song Zhi-Yi| 竹元 嘉利| 飛田 守孝|
抄録 The microstructure of oxidizing magnesium at elevated temperatures has been studied using HR-TEM, SEM and EDS. Two kinds of thin magnesium specimen for TEM observation were prepared. One was oxidized after preparing TEM foil of magnesium, the other was prepared from an oxidized bulk magnesium for observing the cross-section of oxide/Mg interfacial region. In the former, several oxides(MgO) morphologies were observed depending on the temperature and time of the oxidization. The growth of needle-like oxides formed at 573K and mottled oxides formed at 773K were recognized as a remarkable phenomenon belonging to the local oxidization. These oxides were composed of poly-crystal. The thin uniform oxidization layer was also observed in all conditions. In the cross-sectional observation, the local oxide layer, nearly 300nm in thickness, on the matrix(Mg) were observed. The thin uniform oxidized layer of bulk samples was identified as a kind of modified layer (~40nm in thickness) in which the formation of HR-TEM lattice fringes were prevented by the strain due to the slight oxidization.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1997-03-28
31巻
2号
開始ページ 1
終了ページ 10
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002309082
JaLCDOI 10.18926/19585
フルテキストURL Mem_Fac_Eng_OU_29_1_23.pdf
著者 河原 長美| Fukumoto Kohji|
抄録 In this study we investigated the water quality of surface runoff and groundwater runoff from the basins of the Yodo River and the Asahi River based on that separated by a numerical filter. The water quality of the surface runoff is greatly different from the groundwater runoff. The tendency of concentration change in accordance with river discharges is different from each other. The water qtiality of groundwater runoff changes with river discharges clockwise in many cases. The differences of COD and SS originating from those of population and industrial activities in each basin are found in the lower SS concentrations of the surface runoff and the COD cencentrations of the groundwater runoff. The nutrients and chlorine ion were investigated, too.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1994-11-30
29巻
1号
開始ページ 23
終了ページ 34
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002309068
JaLCDOI 10.18926/19584
フルテキストURL Mem_Fac_Eng_OU_29_1_1.pdf
著者 Uno, Yoshiyuki| Kubota, Shin-ichiro| Yokomizo, Seiichi| Ogata, Kojiro| Tada, Nobuhiko|
抄録 Scribing of copper coated alumina ceramic board with Q-switched YAG laser used for the maskless direct patterning of circuit board is experimentally investigated, which leads to efficient production of trial circuit board. Better dividing of alumina circuit board 655μm in thickness can be attained by the scribing of about 100μm depth. Higher repetition frequency of laser irradiation leads to smaller notch angle and lower breaking load.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1994-11-30
29巻
1号
開始ページ 1
終了ページ 6
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002309083
JaLCDOI 10.18926/17853
フルテキストURL Mem_Fac_Eng_OU_43_113.pdf
著者 Sakemi, Yumi| Kato, hidehiro| Nogami, Yasuyuki| Morikawa, Yoshikawa|
抄録 Barreto–Naehrig (BN) curve has been introduced as an efficient pairing-friendly elliptic curve over prime field F(p) whose embedding degree is 12. The characteristic and Frobenius trace are given as polynomials of integer variable X. The authors proposed an improvement of Miller's algorithm of twisted Ate pairing with BN curve by applying X of small hamming weight in ITC–CSCC2008; however, its cost evaluation has not been explicitly shown. This paper shows the detail of the cost evaluation.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 2009-01
43巻
開始ページ 113
終了ページ 116
ISSN 1349-6115
言語 English
論文のバージョン publisher
NAID 120002308945
JaLCDOI 10.18926/17851
フルテキストURL Mem_Fac_Eng_OU_43_108.pdf
著者 Nekado, Kenta| Kato, Hidehiro| Nogami, Yasuyuki| Morikawa, Yoshitaka|
抄録 Recently, pairing-based cryptographies such as ID-based cryptography and group signature have been studied. For fast pairing calculation, not only pairing algorithms but also arithmetic operations in extension field must be efficiently carried out. The authors show efficient arithmetic operations of extension field for Xate pairing especially with Freeman curve.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 2009-01
43巻
開始ページ 108
終了ページ 112
ISSN 1349-6115
言語 English
論文のバージョン publisher
NAID 120002308904
JaLCDOI 10.18926/17849
フルテキストURL Mem_Fac_Eng_OU_43_99.pdf
著者 Kato, Hidehiro| Nogami, Yasuyuki| Morikawa, Yoshitaka|
抄録 A square root (SQRT) algorithm in extension field F(p(m))(m = r(0)r(1)・・・r(n−1)・2(d), r(i) : odd prime, d : positive integer) is proposed in this paper. First, a conventional SQRT algorithm, the Tonelli-Shanks algorithm, is modified to compute the inverse SQRT in F(p(2d)), where most of the computations are performed in the corresponding subfields F(p(2i)) for 0 ≤ i ≤ d-1. Then the Frobenius mappings with addition chain are adopted for the proposed SQRT algorithm, in which a lot of computations in a given extension field F(p(m)) are also reduced to those in a proper subfield by the norm computations. Those reductions of the field degree increase efficiency in the SQRT implementation. The Tonelli-Shanks algorithm and the proposed algorithm in F(p(6)) and F(p(10)) were implemented on a Core2 (2.66 GHz) using the C++ programming language. The computer simulations showed that, on average, the proposed algorithm accelerated the SQRT computation by 6 times in F(p(6)), and by 10 times in F(p(10)), compared to the Tonelli-Shanks algorithm.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 2009-01
43巻
開始ページ 99
終了ページ 107
ISSN 1349-6115
言語 English
論文のバージョン publisher
NAID 120002308980
JaLCDOI 10.18926/17847
フルテキストURL Mem_Fac_Eng_OU_43_93.pdf
著者 Ueno, Hirokazu| Morikawa, Yoshitaka|
抄録 This paper investigates the relation between error distribution and predictive order of minimum mean abusolute error predictors (MMAE predictors) designed for lossless coding of grayscale images. Design of MMAE predictors reduces to the linear programming problem. Let k be the number of coefficients in a predictor (predictor order), we imagine that predictor order k may have a distribution shaping effect. Main purpose of this paper is to ensure that k has such an effect.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 2009-01
43巻
開始ページ 93
終了ページ 98
ISSN 1349-6115
言語 English
論文のバージョン publisher
NAID 120002308979
JaLCDOI 10.18926/17844
フルテキストURL Mem_Fac_Eng_OU_43_75.pdf
著者 大江 啓太| 小西 正躬| 今井 純|
抄録 As is well known, an advanced knowledge and know-how are needed in the design and the diagnosis work. Further, human experts can cope with the recent trend of customers needs. Therefore, the design and the diagnosis work have been privately performed in the past, and its information cannot be shared. In addition, the number of experts is decreasing. It is a very important problem to maintain and to extend experts technologies having been built up. For the purpose, methods and systems for technical inheritance of the advanced techniques of the skilled engineers are needed to train the unskilled operators and also can assist skilled operators. In this research, attention is focused on the design of analog filter circuit. To attain the target, the circuit structural classifier system to support design work is developed. Furthermore, simulation technology for hot strip rolling mills based on distributed agents is presented aimed to develop tools for the diagnosis of hot strip rolling mills operation.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 2009-01
43巻
開始ページ 75
終了ページ 92
ISSN 1349-6115
言語 English
論文のバージョン publisher
NAID 120002308900
JaLCDOI 10.18926/17843
フルテキストURL Mem_Fac_Eng_OU_43_61.pdf
著者 川村 真央| 小西 正躬| Yamagata, Katuki| Shimomura, Koichi|
抄録 In this research, a Human Interface system is designed intended to mobile crane. The intervention of human is unavoidable to attain the high performance of electro mechanical system. As is known, crane operation is complicated. Recently, the decrease of expert person induced crane accident. So in near future, it is required a partial automation of crane operation and human support technology. We are aiming at the development of the operation support system for a crane. In this research, development of the hydro mechanical models representing both of static and dynamics movements are made. Further, actual experimental data of operating mobile crane, which are electrical signal data and three-dimension (3D) position of moving load is measured. The actual operating data are compared with the model and it is found that the developed electromechanical model can explain the behaviors of actual data.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 2009-01
43巻
開始ページ 61
終了ページ 74
ISSN 1349-6115
言語 English
論文のバージョン publisher
NAID 120002308930