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JaLCDOI 10.18926/15466
FullText URL Mem_Fac_Eng_OU_24_1_1.pdf
Author Yoshida, Akira| Ohue, Yuji| Fujii, Masahiro|
Abstract To clarify the effects of a drive system lubricant additive upon rolling fatigue of rollers manufactured from carburized and hardened steel, three types of oil were used as lubricants: one mineral base oil and the other two mineral base oils to which an S-P additive package and ATF additive package were added, respectively. These specimens were tested for sliding/rolling fatigue and examined for failure on the surface, rolling fatigue strength, and other properties. Roller surface temperatures and inter-roller frictional coefficients were found scarcely affected by the type of oil used. Irrespective of the difference in oil type, failure on the surface was found to be entirely spalling attributable to cracks generated in the subsurface. The depth at which spalling cracks had taken place was found nearly coincident with the depth at which a ratio of reversing orthogonal shear stress to hardness had amplitude A(Tyz/Hv) maximized. These depths were larger as Hertz stress became more prominent. Nevertheless, they were found hardly affected by the type of oil. Although rolling fatigue strength did not show a significant difference dependent upon the type of oil, it may be said that fatigue life would be somewhat negatively affected by an extreme pressure coated film with a content of sulfur and phosphorus.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1989-11-29
Volume volume24
Issue issue1
Start Page 1
End Page 12
ISSN 0475-0071
language English
File Version publisher
NAID 120002307588
JaLCDOI 10.18926/15449
FullText URL Mem_Fac_Eng_OU_22_15.pdf
Author Furutani, Yoichiro| Totsuji, Hiroo| Komaki Kunitaka| Tanabe Masahiro|
Abstract 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1988-03-31
Volume volume22
Start Page 15
End Page 34
ISSN 0475-0071
language English
File Version publisher
NAID 120002307361
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 10.18926/15434
FullText URL Mem_Fac_Eng_OU_28_1_27.pdf
Author Totsuji, Hiroo| Tachibana Hiroyuki| Fujimura Hidenori| Nara, Shigetoshi|
Abstract 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1993-11-30
Volume volume28
Issue issue1
Start Page 27
End Page 38
ISSN 0475-0071
language English
File Version publisher
NAID 120002307565
JaLCDOI 10.18926/15423
FullText URL Mem_Fac_Eng_OU_26_1_95.pdf
Author Kawakami, Hiroshi| Konishi, Tadataka|
Abstract This paper describes a method to construct IDEA BANK automatically. IDEA BANK is the data base of the "function-structure module" which is utilized in systematic conceptual design from Value Engineering perspectives. The method based on the Machine Learning EBL technique was evaluated and implemented for the IDEA BANK using SUN workstation. The practical implementation of the IDEA BANK acquisition was discussed after elucidating the problem and solution of the EBL technique in engineering design. In the IDEA BANK system, the structural features of an existing article are analyzed by hierarchically organized domain specific knowledge to yield a systematic explanation of how they function and attain their design goals. The explanation resulted in a generalized version of the Functional Diagram used in Value Engineering from which "function-structure module" can be extracted systematically.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1991-11-30
Volume volume26
Issue issue1
Start Page 95
End Page 108
ISSN 0475-0071
language English
File Version publisher
NAID 120002307756
JaLCDOI 10.18926/15420
FullText URL Mem_Fac_Eng_OU_26_1_61.pdf
Author Kawara, Osami| Danno Hideki| Kunimatsu Takao|
Abstract Lake Biwa is the largest lake in Japan, and one of the most important fresh water resources. The Hino River is the fourth largest river among the rivers which flow into Lake Biwa. The eutrophication of the lake has been warned since the 1960s. In order to improve the water quality of the lake, to decrease the loads through rivers is inevitable. Therefore, it is needed to predict the effects of measures to control pollutant loads and the influence of development in the basin on the loads from rivers before developing the basin and taking measures. This paper deals mainly with the model of water quality management for the Hino River and the effects of the development in the basin on the water quality. The model was formulated considering loads from forests, rice paddy fields, households, housing land, industrial factories. Using this model, a calculation system by a microcomputer was developed and the influence of urbanization of the basin was discussed.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1991-11-30
Volume volume26
Issue issue1
Start Page 61
End Page 73
ISSN 0475-0071
language English
File Version publisher
NAID 120002307182
JaLCDOI 10.18926/15417
FullText URL Mem_Fac_Eng_OU_29_2_39.pdf
Author Oka, Hisao| Sakamoto, Shun-ya| Irie Takashi|
Abstract The body structures under the skin surface, such as bones and tendon, have an influence on the stiffness evaluation observed from the surface. In this case, the observed stiffness should be called an apparent stiffness. To obtain the biomechanical properties of skin itself, the influence of body structure should be removed. This study deals with the correction method of apparent viscoelasticity which calculated from apparent biomechanical impedance. This method is applied to the measured result of the forearm and the right chest to confirm its effectiveness.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1995-03-27
Volume volume29
Issue issue2
Start Page 39
End Page 47
ISSN 0475-0071
language English
File Version publisher
NAID 120002307527
JaLCDOI 10.18926/15416
FullText URL Mem_Fac_Eng_OU_26_1_43.pdf
Author Bouzidi, Moncef| Koga, Ryuji| Wada, Osami| Kagawa, Naoki| Hai Xu| Kosaka, Megumi| Sano HIroya|
Abstract A numerical technique called as "adjoint spectrum" has been proposed by the authors in a previous work. Two applications of it are presented here. It is demonstrated that by generalizing the aspect of adjoint spectrum it becomes possible to measure densities of mixed gases simultaneously. An experimental proof of this has been carried on and simultaneous measurement of densities of both methane and dinitrogen oxide was realized. On the other hand, it is also reported that frequency shifting of spectra, which is a cause of error in spectrometric measurements, can be corrected by exploiting the adjoint spectrum technique in connection with the Taylor expansion. Numerical examples showing the success of this method are reported as well.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1991-11-30
Volume volume26
Issue issue1
Start Page 43
End Page 49
ISSN 0475-0071
language English
File Version publisher
NAID 120002307796
JaLCDOI 10.18926/15406
FullText URL Mem_Fac_Eng_OU_27_2_59.pdf
Author Prokop Jiri| Myojin Sho|
Abstract 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1993-03-25
Volume volume27
Issue issue2
Start Page 59
End Page 71
ISSN 0475-0071
language English
File Version publisher
NAID 120002307384
JaLCDOI 10.18926/15404
FullText URL Mem_Fac_Eng_OU_27_2_41.pdf
Author Prokop Jiri| Myojin Sho|
Abstract 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1993-03-25
Volume volume27
Issue issue2
Start Page 41
End Page 58
ISSN 0475-0071
language English
File Version publisher
NAID 120002307241
JaLCDOI 10.18926/15403
FullText URL Mem_Fac_Eng_OU_27_2_19.pdf
Author Nara, Shigetoshi| Totsuji, Hiroo|
Abstract 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1993-03-25
Volume volume27
Issue issue2
Start Page 19
End Page 40
ISSN 0475-0071
language English
File Version publisher
NAID 120002307451
JaLCDOI 10.18926/15399
FullText URL Mem_Fac_Eng_OU_27_2_1.pdf
Author Kajihara, Yasuhiro| Osaki, Hirokazu|
Abstract 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).
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1993-03-25
Volume volume27
Issue issue2
Start Page 1
End Page 9
ISSN 0475-0071
language English
File Version publisher
NAID 120002307210
JaLCDOI 10.18926/15391
FullText URL Mem_Fac_Eng_OU_27_1_33.pdf
Author Shimada, Yukiyasu| Suzuki, Kazuhiko| Sayama, Hayatoshi|
Abstract Neural nets have recently become the focus of much attention, largely because of their wide range of complex and nonlinear problems. This paper presents a new integrated approach using neural networks for diagnosing process failures. The fault propagation in process is modeled by causal relationships from the fault tree and its minimal cut sets. The measurement patterns required for training and testing the neural network were obtained from fault propagation model. The network is able to diagnose even in the presence of malfunction of certain sensors. We demonstrate via a nitric acid cooler process how the neural network can learn and successfully diagnose the faults.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1992-11-25
Volume volume27
Issue issue1
Start Page 33
End Page 44
ISSN 0475-0071
language English
File Version publisher
NAID 120002307902
JaLCDOI 10.18926/15388
FullText URL Mem_Fac_Eng_OU_27_1_11.pdf
Author Hirashima Masao| Inaba, Hideo|
Abstract 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1992-11-25
Volume volume27
Issue issue1
Start Page 11
End Page 26
ISSN 0475-0071
language English
File Version publisher
NAID 120002307419
JaLCDOI 10.18926/15382
FullText URL Mem_Fac_Eng_OU_35_207.pdf
Author Nakanishi, Toru| Fujiwara Toru|
Abstract In the group signature scheme with a trusted party, a verifier can determine whether or not a signature is made by a member of the group, but cannot identify the member who signed the signature. In case of dispute later on, the signer can be identified by the trusted party. However, for efficient group signature schemes proposed so far, removing a member from the group can be not efficiently performed. In this paper, a group signature scheme with an easy membership canceling is proposed. By sending a request to use a resource together with the group signature on it to the manager of the resource, the manager can control anonymous accesses to the resource. In such an application, the proposed group signature scheme is suitable for canceling of the access privilege.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2001-03-27
Volume volume35
Issue issue1-2
Start Page 207
End Page 212
ISSN 0475-0071
language English
File Version publisher
NAID 120002307232
JaLCDOI 10.18926/15380
FullText URL Mem_Fac_Eng_OU_35_197.pdf
Author Nogami, Yasuyuki| Morikawa, Yoshitaka|
Abstract Modern communication engineerings, such as elliptic curve cryptographies, often requires algebra on finite extension field defined by modulus arithmetic with an irreducible polynomial. This paper provides a new method to detemine the minimal (irreducible) polynomial of a given proper element in finite extension field. In the conventional determination method, as we have to solve the simultaneous equations, the computation is very involved. In this paper, the well known "trace" is extended to higher degree traces. Using the new traces, we yield the coefficient formula of the desired minimal polynomial. The new method becomes very simple without solving the simultaneous equations, and about twice faster than the conventional method in computation speed.
Keywords finite field minimal polynomial irreducible polynomial higher degree trace trace cryptography
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2001-03-27
Volume volume35
Issue issue1-2
Start Page 197
End Page 205
ISSN 0475-0071
language English
File Version publisher
NAID 120002307992
JaLCDOI 10.18926/15379
FullText URL Mem_Fac_Eng_OU_30_1_63.pdf
Author Koshimoto Marcos| Mahmood Zaheed| Kagawa, Yukio|
Abstract Optical fibers or integrated optical waveguides have arbitrary cross-sectional index or refraction distribution. An efficient finite element method for analyzing the propagation characteristics of dielectric / optical waveguides with open boundary is presented. The propagation modes are hybrid, for which a variational expression is formulated in terms of the longitudinal electric and magnetic field components. Infinite elements are introduced to consider open boundary or to extend the region to infinity. Several specific examples are given and the results are compared with those obtained by other approximate methods. Very close agreements have been found.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1995-12-28
Volume volume30
Issue issue1
Start Page 63
End Page 73
ISSN 0475-0071
language English
File Version publisher
NAID 120002307545
JaLCDOI 10.18926/15374
FullText URL Mem_Fac_Eng_OU_30_1_35.pdf
Author Mahmood Zaheed| Kagawa, Yukio|
Abstract Divergence-free shape functions are proposed for the finite elements, with which inhomogeneously-loaded and arbitrarily-shaped waveguides are analysed. The method is based on vectorial finite element formulation employing edge elements. The shape functions used for the approximation of the fields are shown analytically to be divergence-free and as an evidence, the non-physical solutions that appeared in the longitudinal component finite element formulation have been shown to be absent. To show the validity of the elements, application is made for the analysis of rectangular waveguides loaded with dielectric slab and a waveguide with curved structure. The solutions obtained are compared with the analytical ones or the solutions reported elsewhere. The degree of accuracy has been found satisfactory.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1995-12-28
Volume volume30
Issue issue1
Start Page 35
End Page 46
ISSN 0475-0071
language English
File Version publisher
NAID 120002307293
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 10.18926/15362
FullText URL Mem_Fac_Eng_OU_35_97.pdf
Author Yamasaki, Susumu| Kurose, Yoshinori|
Abstract In this paper, we formulate a new integrity constraint in correlation with 3-valued stable models in an abduction framework based on general logic programs. Under the constraint, not every ground atom or its negation is a logical consequence of the theory and an expected abductive explanation, but some atom may be unspecified as a logical consequence by an adjustment. As a reflection of the integrity constraint with an adjustment, we augment an adjusting derivation to Eshghi and Kowalski abductive proof procedure, in which such an unspecified atom can be dealt with.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2001-03-27
Volume volume35
Issue issue1-2
Start Page 97
End Page 135
ISSN 0475-0071
language English
File Version publisher
NAID 120002307812