検索結果 9297 件
JaLCDOI | 10.18926/15452 |
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フルテキストURL | Mem_Fac_Eng_OU_28_2_9.pdf |
著者 | 榊原 精| Kanadani, Teruto| Nakagawa, K.| Yokota, Y.| |
抄録 | 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. |
出版物タイトル | Memoirs of the Faculty of Engineering, Okayama University |
発行日 | 1994-03-15 |
巻 | 28巻 |
号 | 2号 |
開始ページ | 9 |
終了ページ | 12 |
ISSN | 0475-0071 |
言語 | 英語 |
論文のバージョン | publisher |
NAID | 120002307581 |
JaLCDOI | 10.18926/15451 |
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フルテキストURL | Mem_Fac_Eng_OU_22_45.pdf |
著者 | 河野 伊一郎| 西垣 誠| 竹下 祐二| |
抄録 | There are two classifications of the mechanism of levee failure caused by floods; local seepage failure and progressive failure. The fundamental causes of levee failure produced by piping and erosion were studied and the safety of river leves during floods evaluated in terms of soil machanics. The critical hydraulic gradient and the process of progressive failure were obtained from one- and two- dimensional model experiments for piping and erosion. Problems inherent in and preventive measures against levee failure are discussed. In particular, effects of the Tsukinowa method, the most representative Japanese flood fighting method, were studied experimentally and improvements proposed. |
出版物タイトル | Memoirs of the Faculty of Engineering, Okayama University |
発行日 | 1988-03-31 |
巻 | 22巻 |
開始ページ | 45 |
終了ページ | 62 |
ISSN | 0475-0071 |
言語 | 英語 |
論文のバージョン | publisher |
NAID | 120002307536 |
JaLCDOI | 10.18926/15450 |
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フルテキストURL | Mem_Fac_Eng_OU_22_35.pdf |
著者 | 東辻 浩夫| |
抄録 | Several methods to derive thermodynamic sum rules for a system including charged particle are proposed and applied to charged mixtures as well as one-component systems. The validity of the statements is examined carefully with respect to the ordering in the powers of the wave number. As for the mixture of electrons and ions, it is shown how the aspect of the one-component plasma or the ionic mixture appears when electrons become strongly degenerate. |
出版物タイトル | Memoirs of the Faculty of Engineering, Okayama University |
発行日 | 1988-03-31 |
巻 | 22巻 |
開始ページ | 35 |
終了ページ | 44 |
ISSN | 0475-0071 |
言語 | 英語 |
論文のバージョン | publisher |
NAID | 120002307661 |
JaLCDOI | 10.18926/15449 |
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フルテキストURL | Mem_Fac_Eng_OU_22_15.pdf |
著者 | 古谷 洋一郎| 東辻 浩夫| Komaki Kunitaka| Tanabe Masahiro| |
抄録 | An effective potential of an isolated partially ionized high-Z ion, calculated within the framework of the statistical models of atoms, is injected into the one-electron Schrödinger equation, in view of evaluating the electron density and comparing it with the results of statistical models. Starting from this initial value, a self-consistent electron density is obtained on the basis of the density functional theory, where quantum natures of electrons are fully taken into account. |
出版物タイトル | Memoirs of the Faculty of Engineering, Okayama University |
発行日 | 1988-03-31 |
巻 | 22巻 |
開始ページ | 15 |
終了ページ | 34 |
ISSN | 0475-0071 |
言語 | 英語 |
論文のバージョン | publisher |
NAID | 120002307361 |
JaLCDOI | 10.18926/15448 |
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フルテキストURL | Mem_Fac_Eng_OU_28_2_1.pdf |
著者 | 竹元 嘉利| 榊原 精| 飛田 守孝| |
抄録 | Fine particles of Ti-Mo alloy have been prepared by means of arc method, and investigated on internal structure and phase transformation using HR-TEM and EDS. Martensite phase was observed in a particle containing comparatively low concentration of Mo, and ω phase was also found to exist in a nearly 14 % M0 particle. The structure of the ω phase in the fine particle is expanded and remarkably unstable in comparison with the bulk sample, so that it has disappeared in a few seconds during TEM observation. Moreover, the β structure of Ti-Mo particles has changed to the unusual fcc phase with irradiation of a strong electron beam. |
出版物タイトル | Memoirs of the Faculty of Engineering, Okayama University |
発行日 | 1994-03-15 |
巻 | 28巻 |
号 | 2号 |
開始ページ | 1 |
終了ページ | 7 |
ISSN | 0475-0071 |
言語 | 英語 |
論文のバージョン | publisher |
NAID | 120002307644 |
JaLCDOI | 10.18926/15447 |
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フルテキストURL | Mem_Fac_Eng_OU_28_1_129.pdf |
著者 | 谷口 健男| 廣瀬 壮一| Ouchterlony Finn| Nakagawa Kohji| Miyaji Akihiko| Fukuoka Yasufumi| |
抄録 | 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. |
出版物タイトル | Memoirs of the Faculty of Engineering, Okayama University |
発行日 | 1993-11-30 |
巻 | 28巻 |
号 | 1号 |
開始ページ | 129 |
終了ページ | 138 |
ISSN | 0475-0071 |
言語 | 英語 |
論文のバージョン | publisher |
NAID | 120002307126 |
JaLCDOI | 10.18926/15446 |
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フルテキストURL | Mem_Fac_Eng_OU_22_1.pdf |
著者 | 岡 久雄| 山本 辰馬| |
抄録 | Biomechanical impedance is relatively small compared to industrial mechanical impedance. Thus it is difficult to measure it precisely. A biomechanical impedance measuring system was developed for portable use by means of random excitation. This system doesn't require a fixed body and vibrator supporting apparatus. In order to obtain an impedance spectrum, the FFT processing is performed using a personal computer. The spectra of the biomechanical impedance which is measured on body surfaces depend on body positions and can be roughly classified into three spectra patterns : soft, stiff and intermediate. During the measurement, the measuring conditions (preload, diameter of the vibrating tip etc.) influence the results. However, it became clear that the linearity of the biomechanical impedance was satisfied in the limited measuring conditions. Accordingly it is possible to standardize the impedance and to compare it with the results under different measuring conditions. |
出版物タイトル | Memoirs of the Faculty of Engineering, Okayama University |
発行日 | 1988-03-31 |
巻 | 22巻 |
開始ページ | 1 |
終了ページ | 14 |
ISSN | 0475-0071 |
言語 | 英語 |
論文のバージョン | publisher |
NAID | 120002307480 |
JaLCDOI | 10.18926/15445 |
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フルテキストURL | Mem_Fac_Eng_OU_26_2_139.pdf |
著者 | 廣瀬 壮一| |
抄録 | Scattering problems by a penny-shaped crack are solved using a time-domain boundary integral equation method, The crack is located in an infinite homogeneous, isotropic, linearly elastic solid, and is subjected to an oblique incident wave of either P-, SV-, or SH-wave, The hypersingular integral equation is solved to obtain near-field solutions as well as scattered far-fields. The accuracy of the present method is confirmed by comparing the near-field solutions for different arrangement of elements, Scattered far-fields are calculated for various incident waves, and their usefulness in quantitative non-destructive evaluation is discussed. |
出版物タイトル | Memoirs of the Faculty of Engineering, Okayama University |
発行日 | 1992-03-28 |
巻 | 26巻 |
号 | 2号 |
開始ページ | 139 |
終了ページ | 150 |
ISSN | 0475-0071 |
言語 | 英語 |
論文のバージョン | publisher |
NAID | 120002307492 |
JaLCDOI | 10.18926/15444 |
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フルテキストURL | Mem_Fac_Eng_OU_26_2_129.pdf |
著者 | 東辻 浩夫| |
抄録 | The spectrum of Schottky noise in ion storage rings is analyzed as density fluctuations in effectively one-dimensional plasmas. Strong coupling effects in these plasmas are discussed in relation to experimental observations. |
出版物タイトル | Memoirs of the Faculty of Engineering, Okayama University |
発行日 | 1992-03-28 |
巻 | 26巻 |
号 | 2号 |
開始ページ | 129 |
終了ページ | 138 |
ISSN | 0475-0071 |
言語 | 英語 |
論文のバージョン | publisher |
NAID | 120002307668 |
JaLCDOI | 10.18926/15443 |
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フルテキストURL | Mem_Fac_Eng_OU_26_2_111.pdf |
著者 | 奈良 重俊| Banzhaf Wolfgag| |
抄録 | An information processing task which generates combinatorial explosion and program complexity when it is treated by a serial algorithm is investigated using both Genetic Algorithms (GA) and a neural network model (NN). The task in question is to find a target memory from a set of stored entries in the form of "attractors" in a high dimensional state space. The representation of entries in the memory is distributed ("an auto associative neural network" in this paper), and the problem is to find an attractor under a given access information where the uniqueness or even existence of a solution is not always guaranteed ( an ill-posed problem ). The GA is used as an algorithm for generating a search orbit to search effectively for a state which satisfies the access condition and belongs to the target attractor basin in state space. The NN is used to retrieve the corresponding entry from the network. The results of our computer simulation indicate that the present method is superior to a search method which uses random walk in state space. Our technique may prove useful in the realization of flexible and adaptive information processing, since pattern search in high dimensional state spaces is common in various kinds of parallel information processing. |
出版物タイトル | Memoirs of the Faculty of Engineering, Okayama University |
発行日 | 1992-03-28 |
巻 | 26巻 |
号 | 2号 |
開始ページ | 111 |
終了ページ | 128 |
ISSN | 0475-0071 |
言語 | 英語 |
論文のバージョン | publisher |
NAID | 120002307718 |
JaLCDOI | 10.18926/15442 |
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フルテキストURL | Mem_Fac_Eng_OU_28_1_87.pdf |
著者 | Motojima Isao| 河野 伊一郎| 西垣 誠| |
抄録 | 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. |
出版物タイトル | Memoirs of the Faculty of Engineering, Okayama University |
発行日 | 1993-11-30 |
巻 | 28巻 |
号 | 1号 |
開始ページ | 87 |
終了ページ | 128 |
ISSN | 0475-0071 |
言語 | 英語 |
論文のバージョン | publisher |
NAID | 120002307220 |
JaLCDOI | 10.18926/15441 |
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フルテキストURL | Mem_Fac_Eng_OU_26_2_93.pdf |
著者 | 福山 淳| Kasai Takashi| 古谷 洋一郎| |
抄録 | 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. |
出版物タイトル | Memoirs of the Faculty of Engineering, Okayama University |
発行日 | 1992-03-28 |
巻 | 26巻 |
号 | 2号 |
開始ページ | 93 |
終了ページ | 109 |
ISSN | 0475-0071 |
言語 | 英語 |
論文のバージョン | publisher |
NAID | 120002307699 |
JaLCDOI | 10.18926/15440 |
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フルテキストURL | Mem_Fac_Eng_OU_28_1_71.pdf |
著者 | 西垣 誠| Sudinda Teddy| Hishiya Tomoyuki| 河野 伊一郎| |
抄録 | In this paper, method of Eulerian Lagrangian numerical analysis is used to described Advection-Dispersion phenomena. The influence of concentration to the density of fluid is considered. A laboratory model of a two dimensional confined aquifer containing an isotropic, homogeneous porous medium (Hosokawa et.al 1989) was used to validate the applicability of Advection-Dispersion of numerical analysis with steady and unsteady state condition [1]. |
出版物タイトル | Memoirs of the Faculty of Engineering, Okayama University |
発行日 | 1993-11-30 |
巻 | 28巻 |
号 | 1号 |
開始ページ | 71 |
終了ページ | 85 |
ISSN | 0475-0071 |
言語 | 英語 |
論文のバージョン | publisher |
NAID | 120002307975 |
JaLCDOI | 10.18926/15439 |
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フルテキストURL | Mem_Fac_Eng_OU_26_2_77.pdf |
著者 | 和田 修己| Nakajima Masamitsu| |
抄録 | 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. |
出版物タイトル | Memoirs of the Faculty of Engineering, Okayama University |
発行日 | 1992-03-28 |
巻 | 26巻 |
号 | 2号 |
開始ページ | 77 |
終了ページ | 92 |
ISSN | 0475-0071 |
言語 | 英語 |
論文のバージョン | publisher |
NAID | 120002307321 |
JaLCDOI | 10.18926/15438 |
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フルテキストURL | Mem_Fac_Eng_OU_28_1_61.pdf |
著者 | 竹下 祐二| 河野 伊一郎| |
抄録 | 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. |
出版物タイトル | Memoirs of the Faculty of Engineering, Okayama University |
発行日 | 1993-11-30 |
巻 | 28巻 |
号 | 1号 |
開始ページ | 61 |
終了ページ | 69 |
ISSN | 0475-0071 |
言語 | 英語 |
論文のバージョン | publisher |
NAID | 120002307801 |
JaLCDOI | 10.18926/15437 |
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フルテキストURL | Mem_Fac_Eng_OU_28_1_51.pdf |
著者 | 河野 伊一郎| Tanabe Kazuyasu| Tomita Takemitsu| |
抄録 | 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. |
出版物タイトル | Memoirs of the Faculty of Engineering, Okayama University |
発行日 | 1993-11-30 |
巻 | 28巻 |
号 | 1号 |
開始ページ | 51 |
終了ページ | 59 |
ISSN | 0475-0071 |
言語 | 英語 |
論文のバージョン | publisher |
NAID | 120002307254 |
JaLCDOI | 10.18926/15436 |
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フルテキストURL | Mem_Fac_Eng_OU_26_2_69.pdf |
著者 | Fujii, Tatsuo| Sakata Naoki| Nanba, Tokuro| Osaka, Akiyoshi| Miura, Yoshinari| Takada, Jun| |
抄録 | (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. |
出版物タイトル | Memoirs of the Faculty of Engineering, Okayama University |
発行日 | 1992-03-28 |
巻 | 26巻 |
号 | 2号 |
開始ページ | 69 |
終了ページ | 75 |
ISSN | 0475-0071 |
言語 | 英語 |
論文のバージョン | publisher |
NAID | 120002307639 |
JaLCDOI | 10.18926/15435 |
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フルテキストURL | Mem_Fac_Eng_OU_28_1_39.pdf |
著者 | 東辻 千枝子| Matsubara Takeo| |
抄録 | There are some substances in which their hydrogen bonds are considered to play quite important roles in their ferroelectric or antiferroelectric phase transition. These ferroelectrics usually have large isotope effects in phase transition temperatures and we expect the physics of hydrogen bonds is closely related to the effects. We propose a simple model describing the isolated hydrogen bond. Based on quantum-mechanical analyses of this model, we study the difference between the behavior of a proton and a deuteron in hydrogen bonds. |
出版物タイトル | Memoirs of the Faculty of Engineering, Okayama University |
発行日 | 1993-11-30 |
巻 | 28巻 |
号 | 1号 |
開始ページ | 39 |
終了ページ | 50 |
ISSN | 0475-0071 |
言語 | 英語 |
論文のバージョン | publisher |
NAID | 120002307179 |
JaLCDOI | 10.18926/15434 |
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フルテキストURL | Mem_Fac_Eng_OU_28_1_27.pdf |
著者 | 東辻 浩夫| Tachibana Hiroyuki| Fujimura Hidenori| 奈良 重俊| |
抄録 | The ground states of interacting electrons in coupled quantum wires are analyzed on the basis of the density functional theory. The exchange-correlation potential is calculated from 'exact' results given by the Green's function Monte Carlo method in two and three dimensions. It is shown that the critical density signifying the change from symmetrical to asymmetrical ground state is weakly dependent on the details of the exchange-correlation potential. These critical values are compared with the result of the three-dimensional analysis for a single wire. |
出版物タイトル | Memoirs of the Faculty of Engineering, Okayama University |
発行日 | 1993-11-30 |
巻 | 28巻 |
号 | 1号 |
開始ページ | 27 |
終了ページ | 38 |
ISSN | 0475-0071 |
言語 | 英語 |
論文のバージョン | publisher |
NAID | 120002307565 |
JaLCDOI | 10.18926/15432 |
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フルテキストURL | Mem_Fac_Eng_OU_28_1_1.pdf |
著者 | 奈良 重俊| Miho Shigeru| 東辻 浩夫| |
抄録 | The structural stabilities of bulk Si, Ge, and GaAs are discussed based on the total energy evaluated by the summation of the band structure energy and the short-range repulsive potential between ions. The band structure energy is calculated by means of the simple tight-binding method. The tight-binding parameters are determined so as to fit to the results of a pseude potential calculation and Harrison's model is employed to include the influence of lattice deformation. The short-range-force is assumed to be of the exponential form and parameters are determined so as to reproduce an experimental value of bulk modulus. This treatment qualitatively well describes structural properties in spite of the simple computational procedure and roughly gives the known variation of the total energy for a <100> uniaxial strain. This method is able to be applied to an investigation of the structural stabilities of superlattices, for example, a strained layer superlattice consisting of hetero-semiconductors. |
出版物タイトル | Memoirs of the Faculty of Engineering, Okayama University |
発行日 | 1993-11-30 |
巻 | 28巻 |
号 | 1号 |
開始ページ | 1 |
終了ページ | 25 |
ISSN | 0475-0071 |
言語 | 英語 |
論文のバージョン | publisher |
NAID | 120002307238 |