JaLCDOI 10.18926/15490
FullText URL Mem_Fac_Eng_OU_25_1_51.pdf
Author Totsuji, Hiroo|
Abstract The superconductivity proximity effect in the dirty limit is revisited and equations and boundary conditions are obtained for the case of inhomogeneous media with continuously varying characteristic parameters.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1990-12-14
Volume volume25
Issue issue1
Start Page 51
End Page 57
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307188
JaLCDOI 10.18926/15492
FullText URL Mem_Fac_Eng_OU_25_1_59.pdf
Author Kohno, Iichiro| Nishigaki, Makoto| Okada Junji|
Abstract In this paper, we propose a method to determine the coefficients of permeability of the unconfined aquifer consisted of two different permeability layers. With mixing the conventional pumping test and falling head permeability test, the coefficients of permeabilitiy k(1) and k(2) were obtained. The validity of the proposed method is investigated by using the numerical simulation. As the results, it becomes apparent that the proposed method is applicable to real hydarulic problems.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1990-12-14
Volume volume25
Issue issue1
Start Page 59
End Page 69
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307472
JaLCDOI 10.18926/15488
FullText URL Mem_Fac_Eng_OU_25_1_37.pdf
Author Bouzidi, Moncef| Koga, Ryuji| Wada, Osami| Kagawa, Naoki| Hai, Xu| Kosaka, Megumi| Sano, Hiroya|
Abstract Is proposed a tunable diode laser absorption spectrometer system which employs a pulsed current to drive the diode laser still implementing a second-harmonic detection methods enhancing a signal to noise up to 104 times that the case without it. This system affords the lead-salt diode laser a higher operating temperature which allows a more compact deep cooling system. A principle is based on employing a gated integrator between the preamplifier and the lock-in amplifier. Investigations are made on the optimum selection of the gating aperture time interval as determined by response time of the infrared detector and the pulse width of the laser driving current.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1990-12-14
Volume volume25
Issue issue1
Start Page 37
End Page 50
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307549
JaLCDOI 10.18926/15498
FullText URL Mem_Fac_Eng_OU_25_1_99.pdf
Author Nishigaki, Makoto| Takeshita, Yuji| Kono, Iichiro|
Abstract In this paper, a numerical procedure of determining hydraulic properties in multilayered aquifers are presented. From pumping test data in multilayered aquifers, the coefficient of permeability and specific storage for each aquifer are determined by using a combination of finite element analysis and nonlinear least-squares optimization technique. This study especially points out necessity of stress-flow coupling analysis to explain the behaviors of pressure head in multilayered aquifer during pumping test. As a example, practical pumping test data were evaluate and the coefficients of permeability and specific storage of aquifers and aquitard were obtained.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1990-12-14
Volume volume25
Issue issue1
Start Page 99
End Page 109
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307452
JaLCDOI 10.18926/15494
FullText URL Mem_Fac_Eng_OU_25_1_71.pdf
Author Myojin Sho| Yamada Masahito| Fujii Naoto|
Abstract A transportation planning way of approach is applied to optimal pricing and planning of urban expressway network. Two kinds of network are investigated ; four radials with one ring system and four radials with two rings system. The model is composed of three submodels ; road systell, trip generation-attraction and traffic diversion. Some iaplicative aspects are shown of the optimal solutions that maximize the aggregate number of the trips diverted to expressway under constraints ; equilibrium of revenue and expenditure and traffic capacity constraint. (1) traffic flow has the peaks at junctions on radial expressway that are adjusted to be equal to the traffic capacity. (2) two rings system realizes the larger aggregate number of diverted trips by lower toll rate than one ring system does. (3) well-located second ring has a remarkable effect on improvement in accessibility to expressway and (4) some parameters in the model have curious effects on the optimal system.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1990-12-14
Volume volume25
Issue issue1
Start Page 71
End Page 87
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307618
JaLCDOI 10.18926/15486
FullText URL Mem_Fac_Eng_OU_25_1_23.pdf
Author Miura, Yoshinari| Takada, Jun| Osaka, Akiyoshi| Kawamura, Toshio|
Abstract Zinc oxide films were prepared on silica glass substrates by the use of an r.f. activated reactive evaporation (ARE) method, and were examined by X-ray diffraction (XRD) and scanning electron micrograph (SEM). XRD measurements indicate that the films were c-axis oriented and that an r.f. plasma of Zn and O was necessary for the ZnO film deposition. Substrate temperature, oxygen gas pressure, evaporation rate, r.f. power and inlet position of oxygen gas effect the c-axis orientation, the growth rate and the microstructure of the films. Optimum conditions for a dense film with a fine texture of the surface and having good crystallinity were as follows: the substrate temperature;400℃, the evaporation rate;5.0(A)/s, the oxygen pressure;2.0x10(-4) Torr, the r.f. power;150 to 200W, and the oxygen gas inlet near the substrate. For the film prepared under the optimum conditions, the standard deviation σ of the rocking curve for the (002) diffraction was 1.9deg, smaller than that of the film prepared by using an r.f. sputtering method.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1990-12-14
Volume volume25
Issue issue1
Start Page 23
End Page 35
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307600
JaLCDOI 10.18926/15500
FullText URL Mem_Fac_Eng_OU_25_2_1.pdf
Author Okada, Hiroyuki| Hida, Moritaka| Sakakibara, Akira| Takemoto, Yoshito|
Abstract Tensile strength and elongation of cast magnesium reinforced with titanium fiber were measured by tensile test. The pull-out test of a titanium rod partially embedded in a magnesium matrix was performed to evaluate interfacial bonding strength between magnesium and titanium. It was found that when the fiber volume fraction was changed from 1% to 14%, the tensile strength was improved with increase of volume fraction, while the improvement of elongation tended to be restrained beyond the volume fraction of 10%. The interfacial strength was revealed to be strong, and this was substantiated by the scanning electron microscopy showing an excellent wettability between the titanium fiber and the magnesium matrix.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1991-03-28
Volume volume25
Issue issue2
Start Page 1
End Page 8
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307559
JaLCDOI 10.18926/15516
FullText URL Mem_Fac_Eng_OU_25_2_115.pdf
Author Taniguchi, Takeo| Irie Hirotsugu|
Abstract 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1991-03-28
Volume volume25
Issue issue2
Start Page 115
End Page 122
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307316
JaLCDOI 10.18926/15506
FullText URL Mem_Fac_Eng_OU_25_2_17.pdf
Author Sakakibara, Akira| Kanadani, Teruto| Kaneeda, Toshiaki| Hosokawa, Norio|
Abstract Effect of the soft surface layer that was formed on low temperature aging of Al-Zn alloy on fatigue strength was studied under repeated tensile loading. Vickers microhardness test revealed that there existed less hardened region in the vicinity of grain boundary and surface, and that the region extends 50 to 100μm from the surface inward. From the plot of the stress amplitude against the number of cycles to failure, it is concluded that the presence of less hardened surface layer strengthens fatigue resistance of the age hardened Al-Zn alloys containing 8 to 16mass % Zn under the repeated tensile loading.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1991-03-28
Volume volume25
Issue issue2
Start Page 17
End Page 23
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307685
JaLCDOI 10.18926/15517
FullText URL Mem_Fac_Eng_OU_25_2_123.pdf
Author Taniguchi, Takeo| Ohta, Chikashi|
Abstract 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1991-03-28
Volume volume25
Issue issue2
Start Page 123
End Page 133
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307904
JaLCDOI 10.18926/15503
FullText URL Mem_Fac_Eng_OU_25_2_9.pdf
Author Mikuni, Masato| Hida, Moritaka| Nishida, Norihide| Sakakibara, Akira| Yamada, Masuo|
Abstract Strains induced in the Si substrates by TiN film were observed with X-ray topography. The image of the sample with TiN film 0.45μm thick was like that of a dislocation loop observed with transmission electron microscope. The images of the samples with TiN films 1.65, and 1.9μm thick were different; blackening spreaded in the <112> and <110> direction from the ring contrast in shape of four-lobed rosette pattern. Spreading extended 1.6 times longer than the radius of the ring contrast along the <112> direction. The strain field extended 0.1μm in depth from the top surface where TiN was plated. From the topographs of bent Si beam, it was found that the blackness was almost proportional to the strain. The strains induced by TiN film locally ion-plated were smaller than those observed previously when TiN was ion-plated on the whole top surface of the substrate. Fine structures were observed in the topographs which could not be explained by the kinematical theory.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1991-03-28
Volume volume25
Issue issue2
Start Page 9
End Page 15
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307429
JaLCDOI 10.18926/15513
FullText URL Mem_Fac_Eng_OU_25_2_81.pdf
Author Totsuji, Hiroo|
Abstract Numerical methods for the analysis of the proximity effect in superconducting microstructures in the dirty limit are formulated on the basis of the finite element method. One- and two-dimensional cases are considered and third order Hermite shape functions are used. The results are also applicable to investigations of electronic states in semiconductor superlattice structures.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1991-03-28
Volume volume25
Issue issue2
Start Page 81
End Page 93
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307242
JaLCDOI 10.18926/15515
FullText URL Mem_Fac_Eng_OU_25_2_95.pdf
Author Totsuji, Hiroo| Ishikura Satoshi| Takayama Norihisa|
Abstract Critical temperatures of two-dimensional microstructures with superconducting proximity effect in the dirty limit are evaluated for various geometrical constructions. As a numerical method, the finite element method is applied. Guidelines in estimating critical temperatures are given for the case where the decay of superconducting order parameter is either sufficiently slow or fast in comparison with the scale length of the structure.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1991-03-28
Volume volume25
Issue issue2
Start Page 95
End Page 113
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307413
JaLCDOI 10.18926/15510
FullText URL Mem_Fac_Eng_OU_25_2_39.pdf
Author Nsunge Felix Chintu| Tomita, Eiji| Hamamoto, Yoshisuke|
Abstract Velocity distributions and related parameters of transient and steady, turbulent air jets issuing under atmospheric conditions at Mach 0.14, 0.33 and 0.5 have been predicted using Navier-Stokes(N-S) equations for compressible flow and incompressible flow independently with the k-ε model. The closeness and consistence of the results predicted by the N-S equations for compressible and incompressible flows as well as with relevant measurement or similar prediction show that the incompressible flow assumption for at least some subsonic gas jets issuing at velocities higher than Mach 0.3, the general limit for incompressible fluid flow, can be reasonably accurate particularly in the main fully developed flow region. This suggests that the divergence term in source terms of the momentum, turbulence energy and its dissipation rate equations have negligible effects for some seemingly compressible high speed, subsonic free gas jets. The computation time is reduced by at least 18 % when incompressible flow assumption is used.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1991-03-28
Volume volume25
Issue issue2
Start Page 39
End Page 54
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307456
JaLCDOI 10.18926/15508
FullText URL Mem_Fac_Eng_OU_25_2_25.pdf
Author Nsunge Felix Chintu| Tomita, Eiji| Hamamoto, Yoshisuke|
Abstract A suddenly started cold methane gas jet issuing from a 1 mm diameter orifice into still air at Mach one has been predicted using the two-equation, high Reynolds number version of k-ε turbulence model and SIMPLE algorithm which employs so called primitive variables and a hybrid scheme for treating combined diffusion and convection. Global trends of predicted radial distributions of velocity, temperature, methane concentration in the steady rear part of the transient jet and axial jet tip penetration compare reasonably well with universal profiles representing measurement for the steady jet particularly in the fully developed turbulent core and semi-empirical relation for the transient jet respectively. The prediction scheme has shown reasonably good accuracy especially in prediction of main flow parameters of a transient, high speed compressible gas jet issuing into a dissimilar surrounding gas(binary gas mixture jet).
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1991-03-28
Volume volume25
Issue issue2
Start Page 25
End Page 38
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307676
JaLCDOI 10.18926/15511
FullText URL Mem_Fac_Eng_OU_25_2_55.pdf
Author Ohkura Akira| Kameyama, Yoshimasa| Sayama, Hayatoshi| Suzuki, Kazuhiko| Fukumoto Shuichi|
Abstract AHP can handle decision-making problems involving several criteria when some of these are difficult or impossible to compare other than numerically. When a small group of decision makers settle the multi-criteria problem by AHP, the members of group could not often reach an agreement with hierarchic structure involving objectives, criteria, sub-criteria and alternatives because they have different positions, interests, and opinions. Further, the members have different importances for criteria and sub-criteria, and have dissimilar preferences for alternatives. In this article, we reveal the troubleness of AHP in case of being used by a small group of decision makers. Moreover, we proposed a procedure of AHP which the members of group could easily agree with the structure of problem and the weights of criteria etc.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1991-03-28
Volume volume25
Issue issue2
Start Page 55
End Page 67
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307741
JaLCDOI 10.18926/15512
FullText URL Mem_Fac_Eng_OU_25_2_69.pdf
Author Tsuchiya Takao| Kagawa, Yukio|
Abstract A finite element approach to the calculation of nonlinear sound propagation is proposed. Under the assumption of a weak nonlinearity, a linearized one-dimensional equation is considered. The equation is discretized in space, and is then solved for time by using Newmark-β integration scheme, in which a numerical damping is devised. Some numerical demonstrations are made for the nonlinear sound propagation of a single-shot pulse in air. It is shown that the shock wave propagation is stably and accurately simulated by the introduction of the numerical damping.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1991-03-28
Volume volume25
Issue issue2
Start Page 69
End Page 80
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307747
JaLCDOI 10.18926/15421
FullText URL Mem_Fac_Eng_OU_26_1_75.pdf
Author Myojin Sho| Noguchi Hisahumi| Yamada Masahito|
Abstract Four radials-single ring urban expressway network is priced and, simultaneously, optimized in its spatial formation under the constraint that a balance must be kept of revenue and expenditure. The model consists of three sub-models: road system, car trip generation-attraction and traffic diversion. Network performance is assessed on two criteria; trip number criterion on which the aggregate number of car trips diverted onto expressway is maximized and travel hour criterion on which the travel hours of car trips integrated over the road system; surface and expressway, is minimized. Optimization is tried by numerical calculation for some sets of parameters in the model. The results are summarized as follows; (1) simultaneous optimization of price and spatial formation of the expressway network is possible on each of criteria, (2) trip number criterion produces lower pricing and smaller network while travel hour criterion does higher pricing and larger network, (3) optimum solution lies in a delicate relation of price and spatial network formation that comes from the balance constraint.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1991-11-30
Volume volume26
Issue issue1
Start Page 75
End Page 94
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307318
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 英語
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 英語
File Version publisher
NAID 120002307182