JaLCDOI 10.18926/15443
FullText URL Mem_Fac_Eng_OU_26_2_111.pdf
Author Nara, Shigetoshi| Banzhaf Wolfgag|
Abstract 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1992-03-28
Volume volume26
Issue issue2
Start Page 111
End Page 128
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307718
JaLCDOI 10.18926/15445
FullText URL Mem_Fac_Eng_OU_26_2_139.pdf
Author Hirose, Sohichi|
Abstract 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1992-03-28
Volume volume26
Issue issue2
Start Page 139
End Page 150
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307492
JaLCDOI 10.18926/15473
FullText URL Mem_Fac_Eng_OU_26_2_61.pdf
Author Osaka, Akiyoshi| Kawabata Kouji| Nanba, Tokuro| Takada, Jun| Miura, Yoshinari|
Abstract Mullite-dispersed silica ceramics were prepared through sol-gel processing by the use of tetraethoxy silane, aluminium nitrate and aluminium isopropoxide as the Si and Al sources where HCl and HN0(3) were the catalyst. Effect of the starting materials, solvents and catalysts was examined on the gelation time or temperature of mullite precipitation. Apparent activation energy of gelation ranged from 80 to 95kJ/mol. The presence of AI in the sols elongated the gelling time suggesting the formation of chelate bonds between AI and Si-OR or Si-OH bonds.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1992-03-28
Volume volume26
Issue issue2
Start Page 61
End Page 67
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307416
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 英語
File Version publisher
NAID 120002307639
JaLCDOI 10.18926/15427
FullText URL Mem_Fac_Eng_OU_26_2_17.pdf
Author Feng Yibu| Inaba, Hideo| Nozu, Shigeru|
Abstract Heat transfer measurements were conducted during freezing of quiescent water in a horizontal cylinder. A horizontal cylinder with inner diameter of 61.1 mm is cooled by air in a constant low temperature room and time variations of the radial distribution of fluid temperature were observed. Experimental results for the velocity of the phase change interface, the time taken for complete freezing and apparent freezing heat transfer coefficient were compared with the simple theoretical model based on the quasisteady assumption.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1992-03-28
Volume volume26
Issue issue2
Start Page 17
End Page 24
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307382
JaLCDOI 10.18926/15425
FullText URL Mem_Fac_Eng_OU_26_2_1.pdf
Author Inaba, Hideo| Otake, Hideo| Nozu, Shigeru|
Abstract Radiative characteristics of the frost layer melted by radiative heat are experimentally examined. A frost layer is heated from above by the radiative heat from a halogen lamp set. Thermal radiation of the lamp has the wavelength spectrum characteristics similar to those of the solar radiation. The effect of the environmental temperature upon the frost melting process is clarified in experiments. The optical characteristics of reflectivity, absorptivity and transmissivity of the frost layer during the melting of the frost layer are measured using special measuring instruments.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1992-03-28
Volume volume26
Issue issue2
Start Page 1
End Page 16
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307428
JaLCDOI 10.18926/15418
FullText URL Mem_Fac_Eng_OU_26_1_51.pdf
Author Totsuji, Hiroo| Shirokoshi Hideki| Nara, Shigetoshi|
Abstract Variable shape molecular dynamics is formulated for the one-component plasma and the structural transition from the fcc lattice to the bcc lattice has been observed. It is emphasized that the condition of constant volume should be imposed when deformations of periodic boundary conditions are taken into account.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1991-11-30
Volume volume26
Issue issue1
Start Page 51
End Page 59
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307555
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 10.18926/15421
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 10.18926/15420
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
JaLCDOI 10.18926/15412
FullText URL Mem_Fac_Eng_OU_26_1_21.pdf
Author Nozu, Shigeru| Inaba, Hideo|
Abstract A numerical study is performed for the facilitated diffusion of carbon-dioxide in an ultrapure water film flowing downward along a vertical surface. The model adopted for the present work includes the effects of the reaction rate for the hydration of CO(2)in a liquid. Comparison of the total concentration of CO(2) for different film thickness indicates that the effects of the hydration is more remarkable for the thinner liquid film.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1991-11-30
Volume volume26
Issue issue1
Start Page 21
End Page 26
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307958
JaLCDOI 10.18926/15410
FullText URL Mem_Fac_Eng_OU_26_1_9.pdf
Author Uno, Yoshiyuki| Nakajima, Toshikatsu| Okada Minoru|
Abstract Practical utilization of ram type electrical discharge machining in uninflammable fluid has been expected in place of inflammable kerosine type fluid for unmanned operation in a workshop. The electrical discharge machining performance in deionized water is experimentally investigated on the basis of the analysis of the crater generated by a single pulse discharge. The experimental analysis makes it clear that the electrical discharge machining performance in deionized water is greatly affected by the electrode polarity. The metal removal rate in the normal polarity machining is higher than that in reverse polarity machining, while the electrode wear rate in the normal polarity machining is greater than that in reverse polarity machining. Therefore the electrode polarity should be properly selected according to the purpose of machining.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1991-11-30
Volume volume26
Issue issue1
Start Page 9
End Page 20
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307319
JaLCDOI 10.18926/15407
FullText URL Mem_Fac_Eng_OU_26_1_1.pdf
Author Sakakibara, Akira| Kanadani, Teruto|
Abstract Reversion of the age-hardened Al-15mass % Zn alloy, in which ellipsoidal GP zones were formed, was investigated by hardness test. Ellipsoidal zones were reverted more quickly near the surface and grain boundary than in the interior, as spherical zones did. The results confirm their role as sources for vacancies in reversion.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1991-11-30
Volume volume26
Issue issue1
Start Page 1
End Page 7
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002308003
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 英語
File Version publisher
NAID 120002307796
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 英語
File Version publisher
NAID 120002307648
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 10.18926/15510
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 10.18926/15511
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 10.18926/15503
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 10.18926/15508
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