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 Kawara, Osami| 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
JaLCDOI 10.18926/17841
フルテキストURL Mem_Fac_Eng_OU_43_55.pdf
著者 井上 真一郎| 小西 正躬| 今井 純|
抄録 In this research, an image processing method and a system for inspection support of a rod figured cutting tool are developed. As is well known, the visual inspection of a cutting tool by image processing is not easy, because cutting blade have a helical blade structure. To cope with the problem, an experimental facility with rotation and longitudinal tool shift functions to enable acquisition of blade surface pictures along a cutting rod is developed. The type of the defect treated in this paper is the spot of coating on blade surface. To judge the quality of the processed image of blade surface, neural network with autonomous learning is used. The processed image of cutting tool is divided into 64 × 64 blocks used for the input to the neural networks. Before input, each block data is preprocessed applying a edge detection filter and a transformation by the discrete fourier transform (DFT). Using these technologies, the experimental inspection system is built and tested to check the capabilities of the inspection algorithms. The diagnostic performance of the surface defect of a cutting tool was confirmed. There remained a problem to mis judge the normal tools as the defect.
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 55
終了ページ 60
ISSN 1349-6115
言語 English
論文のバージョン publisher
NAID 120002308973
JaLCDOI 10.18926/17839
フルテキストURL Mem_Fac_Eng_OU_43_49.pdf
著者 赤松 慎也| 小西 正躬| 今井 純|
抄録 In this paper, the controlled target is the SCARA robot with two links, and the object is fine control of the arm head position of the robot. To attain the object, Internal Model Control (IMC) is introduced. A nonlinear equations are for robot dynamics formulated by solving Lagrange equation, and is linearized to design control system by IMC. The controller of IMC is designed or synthesisted as the inverse system of the linearized model, and IMC filter model is selected. Also, reference filter is introduced to make the improvement of performance. The result of control performance by IMC is compared with that of PID numerically, accuracy and incoherency are confirmed.
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 49
終了ページ 54
ISSN 1349-6115
言語 English
論文のバージョン publisher
NAID 120002308854
JaLCDOI 10.18926/17837
フルテキストURL Mem_Fac_Eng_OU_43_39.pdf
著者 桑嶋 崇行| 今井 純| 小西 正躬|
抄録 This paper presents method of the controller design for one link arm with parametric uncertainty. Recently, many manufacturing robots are operated in manufacturing facilities, with the aim of labor and cost saving or improvement of the productivity. Such robots need to have positioning performance of high precision. In condition that there is an uncertainty in plant dynamics, desired control performance may not be attained because the controller is designed according to the mathematical model of a plant. So it is important that the designed control system have a robust control performance. In this paper, the robust controller is designed using Quantitative Feedback Theory (QFT) for one link arm with parametric uncertainty. Simulation experiments are run for control system designed by using QFT and conventional method. The results are compared with each other and it is found that the control system designed by QFT shows a robust performance and can suppress the unevenness of output against parametric uncertainty.
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 39
終了ページ 48
ISSN 1349-6115
言語 English
論文のバージョン publisher
NAID 120002308875
JaLCDOI 10.18926/17835
フルテキストURL Mem_Fac_Eng_OU_43_32.pdf
著者 馬渕 周治| 小西 正躬| 今井 純|
抄録 A tractor-trailer vehicle in the factory might move on the route determined beforehand. However, automation of a tractor-trailer vehicle is difficult so that it is necessary to consider the nonlinearity of a vehicle and a trailer. In this research, the effective tracking control method of a tractor-trailer vehicle is proposed. The control method using time-state control form for a preview control is presented, and be applied a tractor-trailer vehicle with nonholonomic characteristics. Results of numerical experiments are presented to check effectiveness of the proposed control method.
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 32
終了ページ 38
ISSN 1349-6115
言語 English
論文のバージョン publisher
NAID 120002308736
JaLCDOI 10.18926/17833
フルテキストURL Mem_Fac_Eng_OU_43_27.pdf
著者 東辻 浩夫|
抄録 When the Coulomb coupling between fine particles becomes sufficiently strong in fine particle plasmas, the isothermal compressibility of the whole system diverges and we have a phase separation and an associated critical point. Experimental conditions of fine particle plasmas, densities and temperatures of components and the fine particle size, are obtained corresponding to characteristic parameters around the critical point and the dependency on ion species and other factors is discussed.
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 27
終了ページ 31
ISSN 1349-6115
言語 English
論文のバージョン publisher
NAID 120002308947
JaLCDOI 10.18926/17831
フルテキストURL Mem_Fac_Eng_OU_43_22.pdf
著者 東辻 浩夫| Chai Hong| 東辻 千枝子| 鶴田 健二|
抄録 For the transfer of quantum information and the creation of entangled states, the application of tuned spin chains, systems of spins with the nearest-neighbor coupling tuned so as to give high efficiency, has been proposed and some examples of high performance have been given by several authors. In this article, the effect of deviations from tuned values and the effect of resultant asymmetry are investigated through numerical simulations and theoretical analyses. It is shown that there exists a system where the transfer efficiency is comparable with exactly tuned ones and, at the same time, robust to noises in the coupling constants. It is also shown that the effect of asymmetry on the efficiency of entanglement creation is of the second order when the asymmetry is small.
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 22
終了ページ 26
ISSN 1349-6115
言語 English
論文のバージョン publisher
NAID 120002308966
JaLCDOI 10.18926/17829
フルテキストURL Mem_Fac_Eng_OU_43_16.pdf
著者 Kurose Tomoyuki| 鶴田 健二| 東辻 千枝子| 東辻 浩夫|
抄録 The finite-difference time-domain (FDTD) method has been applied to the calculation of the phonon band structure of two-dimensional (2D) phononic crystals, consisting of metal cylinders placed periodically in liquid. By comparing several combinations of materials for metal cylinder and liquid, we analyze the dependence of the band structures on sound speed and density of liquid media. Moreover, the negative refraction of the acoustic waves is observed at the interfaces between phononic crystal slab and the liquid. We find that an acoustic“lens effect”with the slab appears due to the negative refractions. The relationship between the focal intensity in the lens effect and the band structure is discussed.
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 16
終了ページ 21
ISSN 1349-6115
言語 English
論文のバージョン publisher
NAID 120002308928
JaLCDOI 10.18926/17826
フルテキストURL Mem_Fac_Eng_OU_43_8.pdf
著者 Umeda Ryosuke| 東辻 千枝子| 鶴田 健二| 東辻 浩夫|
抄録 Metamaterial which has negative permittivity and permeability is investigated via computer simulations. Effects of the nanostructure on dielectric and magnetic properties of the material are taken into account by introducing the Drude-Lorentz model in the materials dispersion. We include multi-band process in the dielectric response in order to reproduce accurately experimental values of bulk Au thin film. Size effect on the dispersion is examined by comparing the model with that of a noble metal particle. Based on the dispersion model constructed, we analyze the electromagnetic response of nanostructured metamaterials to evanescent waves at microwave and optical frequencies via finite-difference time-domain simulatioins on parallel computer. A re- focusing and an amplification of the evanescent waves propagating through a metamaterial, consisting of metal slab/vacuum stacking, is demonstrated for the frequencies of 30GHz and 744THz.
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 8
終了ページ 15
ISSN 1349-6115
言語 English
論文のバージョン publisher
NAID 120002308833
JaLCDOI 10.18926/17822
フルテキストURL Mem_Fac_Eng_OU_43_1.pdf
著者 Shimizu, Kenichi| Torii, Tashiyuki| Ishida, Koki|
抄録 Using a fatigue testing method by which fatigue cracks can be initiated and propagated in a film adhered to cover an elliptical through-hole in a base plate subjected to push-pull cyclic loads, annealed copper films with the thickness of 100μm and those reduced the thickness from the 100μm to 50μm by an electro-polishing were fatigued under a constant stress amplitude with a stress ratio of zero. The crystal rotation behavior with the fatigue crack propagation was investigated by measuring the crystal orientation around the fatigue crack initiated from the notch root before and after fatigue testing, using EBSD (Electron Back-scatter Diffraction) method. Then, the change of crystal orientation with fatigue testing was evaluated quantitatively from the misorientation between the crystal orientation matrix on the same point obtained before and after fatigue testing. As a result, the angle of the crystal rotation obtained from the region showing the high fatigue crack propagation rate was larger than that obtained from the region showing the low fatigue crack propagation rate for the film with the thickness of 100μm, while the fatigue crack propagated faster in the film with the thickness of 50μm than that with the thickness of 100μm regardless of the small crystal rotation angles with the fatigue testing for the film with the thickness of 50μm.
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 1
終了ページ 7
ISSN 1349-6115
言語 English
論文のバージョン publisher
NAID 120002308710
JaLCDOI 10.18926/15517
フルテキストURL Mem_Fac_Eng_OU_25_2_123.pdf
著者 Taniguchi, Takeo| Ohta, Chikashi|
抄録 The aim of this investigation is the proposal of 3D mesh generation method based on the Delaunay triangulation. The method is valid for the finite element modelling of any convex 3D domain into tetrahedra with optimum geometrical configuration. This paper includes the mathematical background of the mesh generation method, its detail, proposal of some efficient tools for faster and more rigorous computations, and some examples of the mesh generation.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1991-03-28
25巻
2号
開始ページ 123
終了ページ 133
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307904
JaLCDOI 10.18926/15516
フルテキストURL Mem_Fac_Eng_OU_25_2_115.pdf
著者 谷口 健男| Irie Hirotsugu|
抄録 Nested dissection method is an elimination method for a set of linear algebraic equations with minimum fillins. Physically it divides a domain into four subdomains, and each subdomain is again divided into four. This procedure is repeated till all nodes are included in some subdomains. Using this characteristic, the authors examine the efficiency of the method on the transputer.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1991-03-28
25巻
2号
開始ページ 115
終了ページ 122
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307316