JaLCDOI 10.18926/15394
フルテキストURL Mem_Fac_Eng_OU_27_1_55.pdf
著者 東辻 浩夫| Tachibana Hiroyuki| Hashimoto Seiji| 奈良 重俊|
抄録 The ground state of a system of electrons accumulated in a pair of coupled symmetric quantum wires is analyzed on the basis of density functional theory. It is shown that, in a domain of physical parameters, electrons are localized in either of wires. The main contribution to the total energy of this system comes from the Hartree energy, or the electrostatic energy, and the exchange-correlation energy between electrons. The ground state is determined by a competition between these contributions: We have symmetric electron distributions when the Hartree energy dominates and asymmetric (localized) states are realized in the opposite case. This kind of simple system with bistable electronic states may be applied to semiconductor memory devices.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1992-11-25
27巻
1号
開始ページ 55
終了ページ 64
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307892
JaLCDOI 10.18926/15392
フルテキストURL Mem_Fac_Eng_OU_27_1_45.pdf
著者 香川 直己| 和田 修己| Hai, Xu| 古賀 隆治| Sano, Hiroya| Inubushi, Kazuyuki|
抄録 A prototype device based on the tunable diode laser absorption spectrometry was constructed and the atmospheric methane concentration near the terrain in a rice paddy field was measured. An open optical path of 50 m length was employed along with a PbSnTe diode laser. Diurnal change of methane density with 30 seconds temporal resolution was recorded associated with meteorological parameters. A feasibility was proven for a practical application for in situ study of atmospheric methane.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1992-11-25
27巻
1号
開始ページ 45
終了ページ 53
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307877
JaLCDOI 10.18926/15390
フルテキストURL Mem_Fac_Eng_OU_27_1_27.pdf
著者 Hirashima Masao| 稲葉 英男|
抄録 Heating and refrigerating technique such as snow melting of road and cold storage by utilizing temperature difference between underground soil and atmosphere is widely used[1-4] in a cold area. In the 1st Report, heat transfer characteristics of two phase closed thermosiphon for extracting geothermal energy is studied fundamentally. In the empirical study, heat extract rate is measured in connection with the change of atmospheric temperature utilizing real two thermosiphons on the site. Temperature distribution on the surface of the thermosiphon and underground soil around it is also measured. Based on the data of the empirical experiment, it is confirmed that prevention of freezing for fire hydrant can be achieved by geothermal heat utilizing two phase closed thermosiphon. Present paper describes the heat transfer behavior of the thermosiphon as the 2nd report.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1992-11-25
27巻
1号
開始ページ 27
終了ページ 32
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307336
JaLCDOI 10.18926/15388
フルテキストURL Mem_Fac_Eng_OU_27_1_11.pdf
著者 Hirashima Masao| 稲葉 英男|
抄録 To prevent freezing of road and aquaduct by extracting geothermal heat with two phase closed thermosiphon has been widely used in a cold area. Both heat transfer characteristics in the underground soil and function of the thermosiphon to extract geothermal heat have to be made clear for the purpose of the above system. This study is directed for the purpose to prevent freezing of fire hydrant and composed of the fundamental experiment and the empirical experiment. In the fundamental study, heat transfer behavior is studied experimentally in the small size filling bath representing the underground soil layer. After recording temperature distribution, heat transfer coefficient is measured, they are proceeded into the correlation between the dimensionless number of Nusselt, Rayleigh and Fourier. The fundamental study is described as the first report.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1992-11-25
27巻
1号
開始ページ 11
終了ページ 26
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307419
JaLCDOI 10.18926/15385
フルテキストURL Mem_Fac_Eng_OU_27_1_1.pdf
著者 Uno, Yoshiyuki| Kubota, Shin-ichiro| Nakajima, Toshikatsu| Ogata, Kojiro| Tada, Nobuhiko|
抄録 Direct patterning of copper coated ceramic circuit board is experimentally investigated with Q-switched Nd:YAG laser in order to shorten the time of the trial manufacture of electronic circuit board and to adapt the flexible design change. It is pointed out that the fast direct patterning the speed of which reaches about 100 mm/s is possible if the repetition frequency and the average power are selected properly. Furthermore cutting off and/or drilling of ceramic board are also possible under the condition that the repetition frequency is less than 3kHz. This technique makes it possible the mask1ess patterning of ceramic circuit board which has been widely used recently in place of conventional glass-epoxy or phenolic resin circuit board, and it leads to the shorter time limit of delivery as compared with the conventional end-milling method.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1992-11-25
27巻
1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 120002307702
JaLCDOI 10.18926/15404
フルテキストURL Mem_Fac_Eng_OU_27_2_41.pdf
著者 Prokop Jiri| Myojin Sho|
抄録 The fundamental objective of this paper is to aggregate and establish a set of practical principles, guidelines, and procedures to clarify and improve classification yard design and to enhance the efficiency of the design process. The paper primarily addresses theoretical and technical aspects of hump yard height and grade design, placement of the switches and the retarders. It attempts to compile and document yard design procedures, based on the Theory of Energy Head and Energy Loss. This procedures are applicable to the design of new yards, rehabilitation of the existing yards of different types and sizes including manually operated as well as highly automated classification yards.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1993-03-25
27巻
2号
開始ページ 41
終了ページ 58
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307241
JaLCDOI 10.18926/15370
フルテキストURL Mem_Fac_Eng_OU_27_2_73.pdf
著者 Kroumov Valeri T.| 井上 昭| 増田 士朗|
抄録 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.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1993-03-25
27巻
2号
開始ページ 73
終了ページ 85
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307731
JaLCDOI 10.18926/15399
フルテキストURL Mem_Fac_Eng_OU_27_2_1.pdf
著者 梶原 康博| 大崎 紘一|
抄録 Precedence relation in assembly has been determined by experience only. Now, an expert system is developed for determining such precedence relation. The conjugate states of the units of a product are shown in face frames and unit frames following the frame model. Seven rules are formulated. They consider geometrical interference of units, and make the precedence relation enable operation time to be shorter, and the number of JIG and substandards to be smaller. These rules are programized by computer language(PROLOG).
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1993-03-25
27巻
2号
開始ページ 1
終了ページ 9
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307210
JaLCDOI 10.18926/15406
フルテキストURL Mem_Fac_Eng_OU_27_2_59.pdf
著者 Prokop Jiri| Myojin Sho|
抄録 The paper presents methods for simulation and examination of the performance of a classification yard, including both manual and computer-aided methods. Presented methods are applicable to the simulation and examination of full range of yards of different types and sizes including manually operated as well as highly automated classification yards.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1993-03-25
27巻
2号
開始ページ 59
終了ページ 71
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307384
JaLCDOI 10.18926/15400
フルテキストURL Mem_Fac_Eng_OU_27_2_11.pdf
著者 岡 久雄| 山本 辰馬| Saratani Keiji| Tanaka Masahiro| Kawazoe Takayoshi|
抄録 The use of dental implants has increased together with increases in the human life span and it has become an imperative subject for dentists to familiarize themselves with this treatment modality. Unfortunately, there has been no practical and quantitative method for in vivo evaluation of the stability of dental implants. In the tooth mobility examination, the tactile sense of natural teeth is different from that of dental implants. The authors have developed an automatic diagnosis system of tooth mobility for clinical use. The biomechanical mobility of peri-implantium is measured with a pseudo-random vibration, from which the viscoelasticity c1, c2, k of peri-implantium is obtained. The diagnosis system has been applied to the quantitative evaluation of the stability of implants : endodontics endosseous implants (titanium pin), endosseous implants (Bioceram). It has also been applied to the evaluation of the long-term prognoses of dental implantation (Bioceram) and the examination of Intramobile implant (IMZ), and the satisfactory results have been obtained.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1993-03-25
27巻
2号
開始ページ 11
終了ページ 17
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002308018
JaLCDOI 10.18926/15403
フルテキストURL Mem_Fac_Eng_OU_27_2_19.pdf
著者 奈良 重俊| 東辻 浩夫|
抄録 Numerical simulations of a single layer recurrent neural network model in which the synaptic connection matrix is formed by summing cyclic products of succesive patterns show that complex dynamics can occur with the reduction of a connectivity parameter which is the number of connection between neurons. The structure in these dynamics is discussed from the viewpoint of realizing complex function using complex dynamics.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1993-03-25
27巻
2号
開始ページ 19
終了ページ 40
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307451
JaLCDOI 10.18926/15442
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
28巻
1号
開始ページ 87
終了ページ 128
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307220
JaLCDOI 10.18926/15434
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
28巻
1号
開始ページ 27
終了ページ 38
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307565
JaLCDOI 10.18926/15438
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
28巻
1号
開始ページ 61
終了ページ 69
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307801
JaLCDOI 10.18926/15440
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
28巻
1号
開始ページ 71
終了ページ 85
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307975
JaLCDOI 10.18926/15432
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
28巻
1号
開始ページ 1
終了ページ 25
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307238
JaLCDOI 10.18926/15435
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
28巻
1号
開始ページ 39
終了ページ 50
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307179
JaLCDOI 10.18926/15437
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
28巻
1号
開始ページ 51
終了ページ 59
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307254
JaLCDOI 10.18926/15447
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
28巻
1号
開始ページ 129
終了ページ 138
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307126
JaLCDOI 10.18926/15458
フルテキストURL Mem_Fac_Eng_OU_28_2_33.pdf
著者 Wang, Ming| Ahmed, Anis| 和田 修己| 古賀 隆治|
抄録 Proposed here is a convenient optical system to collimate the crescent shaped blue laser beam radiated from a Cerenkov SHG in channel waveguide configuration. This collimation system is consisted of a parabolic mirror and has a very large tolerance to the mirror displacement. The anisotropy of the nonlinear crystal on which the waveguide is fabricated has been taken into account. The optimum mirror location is given to obtain a collimated blue laser beam with an aberration less than 0.07λ. By using an objective lens, the collimated beam can be focused down to a thin beam with the spot size less than 1μm.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1994-03-15
28巻
2号
開始ページ 33
終了ページ 44
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307149