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JaLCDOI 10.18926/15453
FullText URL Mem_Fac_Eng_OU_28_2_13.pdf
Author Kusumoto, Hisao| Hida, Moritaka| Sakakibara, Akira| Nishida, Norihide| Takemoto, Yoshito| Yamada, Masuo|
Abstract The strain in Si substrate induced by locally ion-plated thin film of TiN was observed by X-ray topograph (Lang technique). Circular TiN film was deposited on one side of the Si surface. In all topographs the highest blackness attributed to kinematical diffraction effect occurred at the film edge. Rosette pattern with four-lobes was observed around the film. Blackness as a whole increased with the film thickness. Strain was observed in the depth direction of substrate by limited projection method. When the slit width was narrowed, the kinematical images disappeared, and white images appeared at the film edge. All the contrast disappeared when the TiN film was completely removed in boiling HNO(3). The strain induced by the film deposition was proved to be elastic.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1994-03-15
Volume volume28
Issue issue2
Start Page 13
End Page 20
ISSN 0475-0071
language English
File Version publisher
NAID 120002307150
JaLCDOI 10.18926/15452
FullText URL Mem_Fac_Eng_OU_28_2_9.pdf
Author Sakakibara, Akira| Kanadani, Teruto| Nakagawa, K.| Yokota, Y.|
Abstract The state above the solubility temperature of GP zones of Al-3mass % Mg alloy, which has a tendency for precipitation and preprecipitation at low temperature, was studied by resistivity measurement. Homogenization treatment at high temperature reduced Mg atoms in the surface layer. After quenching from 623K, the specimen was annealed sequentially at various temperatures above the GP zone solvus. The stationary resistivity obtained in annealing at a temperature was the same irrespective of the starting state and increased with decreasing annealing temperature. No precipitation was observed in the annealing. The results are not in favor of the segregation of Mg atoms to the dislocation loops but of the short range clustering.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1994-03-15
Volume volume28
Issue issue2
Start Page 9
End Page 12
ISSN 0475-0071
language English
File Version publisher
NAID 120002307581
JaLCDOI 10.18926/15447
FullText URL Mem_Fac_Eng_OU_28_1_129.pdf
Author Taniguchi, Takeo| Hirose, Sohichi| Ouchterlony Finn| Nakagawa Kohji| Miyaji Akihiko| Fukuoka Yasufumi|
Abstract The testing method of rock toughness is proposed by the international society of rock mechanics (ISRM), but the results may be influenced by the test pieces, and the details of the crack propagation and the stress intensity factors are not clarified through the testing. Also the experimental test requires tedious works for the preparation of test specimen and economical responsibility. The present study aims to simulate numerically the rock toughness testing which is proposed by ISRM. For this purpose, the authors propose a numerical method which can simulate the experimental testing, and they show the propriety of the proposed method by comparing the results with the experimental and other numerical methods. At the same time, they clarify the details of crack propagation behaviors in rocks, and show the change of the stress intensity factors. The proposed method is based on the displacement-type finite element method, and several techniques are introduced to obtain accurate solution of the mechanical behavior near the crack-tip area.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1993-11-30
Volume volume28
Issue issue1
Start Page 129
End Page 138
ISSN 0475-0071
language English
File Version publisher
NAID 120002307126
JaLCDOI 10.18926/15442
FullText URL Mem_Fac_Eng_OU_28_1_87.pdf
Author Motojima Isao| Kono, Iichiro| Nishigaki, Makoto|
Abstract In recent years, construction or planning of large-scale underground structures, such as underground power plants, underground oil storage plants and nuclear power plants have been coming into consideration in Japan. To construct such as large-scale underground structures, one of the most important problems is to make clear beforehand the behavior of groundwater around these structures and the other is to carry out proper countermeasure of groundwater, so that these structures can be constructed safely and maintained stability over a long time period. This report describes the results of theoretical studies on the drain systems and at the same time, discusses the drain systems around the underground cavern for the practical underground power stations.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1993-11-30
Volume volume28
Issue issue1
Start Page 87
End Page 128
ISSN 0475-0071
language English
File Version publisher
NAID 120002307220
JaLCDOI 10.18926/15441
FullText URL Mem_Fac_Eng_OU_26_2_93.pdf
Author Fukuyama, Atsushi| Kasai Takashi| Furutani, Yoichiro|
Abstract A one-dimensional tokamak transport code (TASK/TR) has been developed to analyze the evolution of a burning plasma accompanied with fusion reaction. This code deals with the electrons, deuterons, tritons, thermalized α particles, fast α particles and beam ions, separately, in order to describe the dependence of the reaction rate on the ion mixture ratio. As an energy transport model, the drift wave turbulence mode is employed. The heating and current drive by the neutral beam injection as well as the pellet injection for fuelling are also included. This code is applied to a reactor-grade plasma aimed at in the ITER project. The cases of an ignited plasma and a current-driven plasma are examined. The required power for full current drive is estimated. The effect of pellet injection, both fuel and impurity ions, is also studied.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1992-03-28
Volume volume26
Issue issue2
Start Page 93
End Page 109
ISSN 0475-0071
language English
File Version publisher
NAID 120002307699
JaLCDOI 10.18926/15439
FullText URL Mem_Fac_Eng_OU_26_2_77.pdf
Author Wada, Osami| Nakajima Masamitsu|
Abstract This paper describes a method to design an antenna to focus millimeter-wave beam generated by a gyrotron. The antenna, which has been proposed by the authors, consists of a stair-cut circular waveguide and two cylindrical reflectors; one is elliptic and the other is parabolic. Its principle is based on the geometrical optics though slightly modified to consider the diffraction effect. Results of low-power experiments agree well with the design on beam direction, beam width and the position of the focal point. At 35.5 GHz using TE(01) mode, a focused beam with half-power thickness of 13 mm x 10 mm was obtained. This type of antennas find applications to millimeter-wave scattering measurement in fusion plasma research and high- energy-density source for material heating.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1992-03-28
Volume volume26
Issue issue2
Start Page 77
End Page 92
ISSN 0475-0071
language English
File Version publisher
NAID 120002307321
JaLCDOI 10.18926/15438
FullText URL Mem_Fac_Eng_OU_28_1_61.pdf
Author Takeshita, Yuji| Kohno, Iichiro|
Abstract Knowledge of the unsaturated soil hydraulic properties is essential requirement for prediction of seepage flow and contaminant transport through the vadose zone. Unfortunately, these parameters are usually time consuming and expensive to measure in the field and laboratory. At the present condition, there are few data accumulation for Japanese soils. In this paper, van Genuchten's closed-form expressions are described to estimate unsaturated soil hydraulic properties. To evaluate the adequacy of these expressions, comparisons are performed between observed and calculated unsaturated hydraulic properties for typical Japanese soils.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1993-11-30
Volume volume28
Issue issue1
Start Page 61
End Page 69
ISSN 0475-0071
language English
File Version publisher
NAID 120002307801
JaLCDOI 10.18926/15437
FullText URL Mem_Fac_Eng_OU_28_1_51.pdf
Author Kohno, Iichiro| Tanabe Kazuyasu| Tomita Takemitsu|
Abstract A technique for determining the layer structure and content of clay minerals was developed based on the relationship between temperature, and moisture characteristics of clay minerals. Moisture content in standard specimens, prepared by mixing montmorillonite, kaolinite and quartz in various proportions, was determined by measuring weight loss after heating. Based on the results from differential thermal analysis tests, the ignition loss method was found to be widely applicable to clays with montmorillonite and kaolinite as the main components. Dehydration of constituent water occurred at 530℃ and 800℃ in two- and three-layered clay minerals, respectively.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1993-11-30
Volume volume28
Issue issue1
Start Page 51
End Page 59
ISSN 0475-0071
language English
File Version publisher
NAID 120002307254
JaLCDOI 10.18926/15436
FullText URL Mem_Fac_Eng_OU_26_2_69.pdf
Author Fujii, Tatsuo| Sakata Naoki| Nanba, Tokuro| Osaka, Akiyoshi| Miura, Yoshinari| Takada, Jun|
Abstract (001)-oriented Ti(2)O(3) films were epitaxially grown on a(001)-face of sapphire single-crystalline substrate by an activated reactive evaporation method. The formation ranges of stoichiometric and nonstoichiometric Ti(2)O(3) films were determined as a function of the substrate temperature (Ts), the oxygen pressure (Po(2)) and the deposition rate. Stoichiometric Ti(2)O(3) films were grown at Ts≧673K under Po(2)≧1.0×10(-4)Torr, which showed the metal-insulator transition with a sharp change in electrical resistivity from 3.5×10(-2) to 2.6×10(-3)Ωcm at 361K. Nonstoichiometric films prepared under less oxidized conditions did not exhibit the transition. The nonstoichiometry of the Ti(2)O(3)films was discussed in terms of excess Ti ions.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1992-03-28
Volume volume26
Issue issue2
Start Page 69
End Page 75
ISSN 0475-0071
language English
File Version publisher
NAID 120002307639
JaLCDOI 10.18926/15429
FullText URL Mem_Fac_Eng_OU_26_2_25.pdf
Author Matsuda, Masaaki| Osaki, Hirokazu|
Abstract The eye movement has been studied widely, because it gives various information about the characteristics of visual work. Almost all of those studies have concentrated on the distribution of the visual points, the direction and width of the saccadic movement and the fixation time of the measures. However there are few measures to evaluate the relationship between the visual objects and eye movement. Recently, the personal computer become portable and this makes it possible to analyze the many data and to show the results graphically on the experimental field. In this study, we propose a series of methods to evaluate how a subject looks at a visual field using the queue theory, and how often man looks at the central part of the visual field using the statistical two-dimensional ellipse. We developed the Pascal program on an personal computer(NEC PC9800). This program has 3 functions. One is the measurement of eye movement, the second is the calculation of the proposed measures and the third is the display of the results of these calculations.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1992-03-28
Volume volume26
Issue issue2
Start Page 25
End Page 41
ISSN 0475-0071
language English
File Version publisher
NAID 120002308015
JaLCDOI 10.18926/15414
FullText URL Mem_Fac_Eng_OU_26_1_27.pdf
Author Tomita, Eiji| Nsunge Felix Chintu| Hamamoto, Yoshisuke|
Abstract Distributions of hydrogen gas concentration in a suddenly started, single shot hydrogen gas jet issuing from a 1 mm diameter injector into still air were measured using laser interferometry method. This unsteady, turbulent free jet flow has also been calculated using the two-equation, high Reynolds number version of k-ε turbulence model and hybrid scheme for treating combined diffusion and convection in the SIMPLE algorithm. The injection pressure was 0.5 MPa for which predicted and measured temporal jet tip penetration distributions indicate that the jet discharged into still air at Mach 0.25. The level of agreement between present prediction and measurement is good in some regions and poor in others.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1991-11-30
Volume volume26
Issue issue1
Start Page 27
End Page 41
ISSN 0475-0071
language English
File Version publisher
NAID 120002307648
JaLCDOI 10.18926/15405
FullText URL Mem_Fac_Eng_OU_30_2_39.pdf
Author Totsuji, Chieko|
Abstract A simple model for oxygen ion conduction in perovskite compounds is proposed. The potential for an oxygen ion is calculated as the sum of the long range Coulomb potential and short range repulsive potential in a cubic lattice. The activation energy is estimated as the difference in the values of potential at the barrier and at the stable site. When appropriate conditions are satisfied, the activation energy has a minimum as a function of lattice constant in accordance with recent experiments.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1996-03-29
Volume volume30
Issue issue2
Start Page 39
End Page 43
ISSN 0475-0071
language English
File Version publisher
NAID 120002307769
JaLCDOI 10.18926/15402
FullText URL Mem_Fac_Eng_OU_30_2_27.pdf
Author Totsuji, Hiroo| Kishimoto, Tokunari| Totsuji, Chieko|
Abstract The behavior of the Yukawa system in external one-dimensional force fields is analyzed by the molecular dynamics simulation. The formation of layered structures at low temperatures is observed and the relation between the number of layers and characteristic parameters of the system is obtained. Since the Yukawa system serves as a model of clouds of dust particles in plasmas (dusty plasma) which play an important role in plasma processes of semiconductor engineering, the results may be useful to control the quality of semiconductor wafers in such processes. In simulations, periodic boundary conditions are imposed in two dimensions and deformations of periodic boundaries are allowed in order to reduce the effect of boundaries without giving too much constraint on the symmetry.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1996-03-29
Volume volume30
Issue issue2
Start Page 27
End Page 37
ISSN 0475-0071
language English
File Version publisher
NAID 120002307582
JaLCDOI 10.18926/15397
FullText URL Mem_Fac_Eng_OU_30_2_1.pdf
Author Takemoto, Yoshito| Hida, Moritaka| Sakakibara, Akira|
Abstract The mechanism of brittle fracture in Ti-14mass % Mo alloy aged for 1x10(6)s at 623K was studied using transmission electron microscopy (TEM) and dynamic hardness test (DHT) on the structure deformed by means of tensile elongation at elevated temperature or cold rolling. Many band products were observed by TEM in either deformed specimens. These band products were identified to neither slips nor twinning bands, moreover, they were different from α , α ' and α " phases. The band product consisted of β phase and granular unknown phase which was transformed by deformation from ω phase. The newly discovered phase, named β" phase, in the band products had a body-centered triclinic structure. The β" was similar to the ω zone with respect to the morphology and the concentration of Mo, but it resembled β in structure. The result of DHT on the band products and the matrix showed that the band products were softer than the matrix. It is suggested that the band products are easily deformed because of the disappearance of obstacles such as ω phase, and consequently behave like paths to lead cracks preferentially.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1996-03-29
Volume volume30
Issue issue2
Start Page 1
End Page 7
ISSN 0475-0071
language English
File Version publisher
NAID 120002307225
JaLCDOI 10.18926/15387
FullText URL Mem_Fac_Eng_OU_30_2_9.pdf
Author Sakakibara, Akira| Kanadani, Teruto|
Abstract Fatigue strength of Al-Cu alloy was examined by a repeated tensile mode when the specimens were aged and reversion annealed. The specimen quenched from 723K and aged fully around room temperature showed fatigue strength which depended on the existence of soft layer, while the specimen quenched from 723K and aged in the same way showed fatigue strength independent of the existence of the soft layer. Fatigue strength of the specimen, of which the soft surface layer was removed, was the same for either quenching temperature. Fatigue strength became higher when the soft surface layer was thickened with reversion annealing for 600s at 323K after aging. The soft surface layer was thought to increase fatigue strength of the aged Al-Cu alloy as well as Al-Zn alloy.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1996-03-29
Volume volume30
Issue issue2
Start Page 9
End Page 13
ISSN 0475-0071
language English
File Version publisher
NAID 120002307694
JaLCDOI 10.18926/15383
FullText URL Mem_Fac_Eng_OU_30_1_89.pdf
Author Totsuji, Chieko| Sanaka Yoshiaki| Totsuji, Hiroo|
Abstract Based on the tight-binding method, electronic bands of the mixed perovskite oxides are calculated in order to develop the electronic theory of ferroelectric phase transitions in these mixtures which are difficult to describe within the phenomenological theories. Diagonal elements of Hamiltonian matrix of parent materials are assumed to differ by 0.1eV and mixtures are simulated by lattices of supercells containing 2(3) = 8 or 3(3) = 27 unit cells randomly assigned to either material. The width of the conduction and valence bands have maxima and the band gap has a minimum at intermediate mixing ratio. Results are in agreement with those of other analyses on random systems and even 2(3)-cell computation seems to serve as a first approximation for our purpose.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1995-12-28
Volume volume30
Issue issue1
Start Page 89
End Page 97
ISSN 0475-0071
language English
File Version publisher
NAID 120002307957
JaLCDOI 10.18926/15371
FullText URL Mem_Fac_Eng_OU_35_163.pdf
Author Uchiyama Hiromitsu| Miyazaki Satoshi| Osaki, Hirokazu| Kajihara, Yasuhiro| Munesawa, Yoshiomi| Matsuki Katsunori|
Abstract We develop an assembly robot system for assembling the flexible belt-shaped subject. An image processing method is developed to recognize the belt-shaped subject. This method is able to determine the grasping point and grasping angle for piking up a subject by a multiple hands unit. CAD information is used to determine the grasping point. The multiple hands unit is developed, which is able to grasp all grasping points of a subject at a time. In addition, the image processing method is used to judge whether a subject is fastened accurately at right position or not during the assembly.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2001-03-27
Volume volume35
Issue issue1-2
Start Page 163
End Page 168
ISSN 0475-0071
language English
File Version publisher
NAID 120002307229
JaLCDOI 10.18926/15370
FullText URL Mem_Fac_Eng_OU_27_2_73.pdf
Author Kroumov Valeri T.| Inoue, Akira| Masuda, Shiro|
Abstract This report deals with the problem of designing an adaptive observer for estimating unknown periodical disturbances. This is very practical problem because in the area of control of servomechanisms such disturbances are always encountered. When the disturbance cannot be directly measured or eliminated at the source it is necessary to perform a prediction. When a periodical disturbance is present the frequencies appear as unknown parameters and they have to be identified. In order to identify the unknown parameters, it is necessary to transform the composite system model, which contains the models of the controlled system and the disturbances, into observable canonical form. In addition, an inverse transformation is required to calculate the estimates of the present disturbances. In this report, firstly, a review of an adaptive observer for estimation of unknown periodical disturbances is presented. Later a calculation of the disturbance estimate is derived using the algebraic programming system REDUCE. The proposed method here allows to perform all the necessary transformations and to obtain the disturbance estimation without using the transformation matrix. The calculations of these transformations are complicated and, hitherto, there is no simple method to perform them. The results of disturbance estimation are illustrated by two examples.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1993-03-25
Volume volume27
Issue issue2
Start Page 73
End Page 85
ISSN 0475-0071
language English
File Version publisher
NAID 120002307731
JaLCDOI 10.18926/15368
FullText URL Mem_Fac_Eng_OU_35_155.pdf
Author Takahashi Hiromitsu| Munesawa, Yoshiomi| Kajihara, Yasuhiro| Osaki, Hirokazu| Wada Yatarou|
Abstract This paper proposes a concept of a mobile type maintenance robot (MMR in shortly) that is controlled by the tele-operation for assuring the safety and health improvement of work forces. The main components of this system are the industrial robot, an image processing unit, vehicle and computers for tele-operation. Our focus is paid on a method that determine a pathway to move every places where troubles would occur. This method makes it possible that the MMR could arrive any place in the factory with three times of turns at most. Additionally, turning radius of the vehicle is considered for correcting the pathway near the corners to make it possible that it arrives to the place accurately.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2001-03-27
Volume volume35
Issue issue1-2
Start Page 155
End Page 161
ISSN 0475-0071
language English
File Version publisher
NAID 120002307844
JaLCDOI 10.18926/15366
FullText URL Mem_Fac_Eng_OU_35_147.pdf
Author Yamagiwa, Masashi| Sakai, Hiroshi|
Abstract The Cry4A toxin is a dipteran-specific insecticidal protein produced by Bacillus thuringiensis subsp. israelensis as a protoxin of 130 kDa. Its active form is a heterodimer of 20- and 45-kDa fragments which is generated by an interhelical cleavage of a 60-kDa intermediate at the position of Gln236 between α5 and α6 helices in domain I. On the other hand, Cry1Aa, which is also produced as a 130-kDa protoxin but toxic to lepidopteran larvae, was processed into the active 60-kDa fragment with no additional cleavage. To investigate the role of the intramolecular cleavage of Cry4A for its insecticidal activity, the loop between α5 and α6 of Cry4A which includes the cleavage site was substituted for the corresponding region of Cry1Aa. The resulting mutant designated GST-60Loop was expressed as a GST-fusion protein. A difference of the processing profile was observed between GST-60 and GST-60Loop in the in vitro digestion assay by trypsin, and the insecticidal activity of GST-60Loop was two-fold lower than that of GST-60. These results suggested that the interhelical cleavage of Cry4A promoted the toxicity against C. pipiens larvae.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2001-03-27
Volume volume35
Issue issue1-2
Start Page 147
End Page 154
ISSN 0475-0071
language English
File Version publisher
NAID 120002307324