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 10.18926/15414
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 10.18926/15416
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 10.18926/15412
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 10.18926/15421
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 10.18926/15427
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 10.18926/15444
FullText URL Mem_Fac_Eng_OU_26_2_129.pdf
Author Totsuji, Hiroo|
Abstract 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1992-03-28
Volume volume26
Issue issue2
Start Page 129
End Page 138
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307668
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 10.18926/15441
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 英語
File Version publisher
NAID 120002307699
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 10.18926/15445
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 10.18926/15439
FullText URL Mem_Fac_Eng_OU_26_2_77.pdf
Author Wada, Osami| Nakajima Masamitsu|
Abstract 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1992-03-28
Volume volume26
Issue issue2
Start Page 77
End Page 92
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307321
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 10.18926/15429
FullText URL Mem_Fac_Eng_OU_26_2_25.pdf
Author Matsuda, Masaaki| Osaki, Hirokazu|
Abstract The eye movement has been studied widely, because it gives various information about the characteristics of visual work. Almost all of those studies have concentrated on the distribution of the visual points, the direction and width of the saccadic movement and the fixation time of the measures. However there are few measures to evaluate the relationship between the visual objects and eye movement. Recently, the personal computer become portable and this makes it possible to analyze the many data and to show the results graphically on the experimental field. In this study, we propose a series of methods to evaluate how a subject looks at a visual field using the queue theory, and how often man looks at the central part of the visual field using the statistical two-dimensional ellipse. We developed the Pascal program on an personal computer(NEC PC9800). This program has 3 functions. One is the measurement of eye movement, the second is the calculation of the proposed measures and the third is the display of the results of these calculations.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1992-03-28
Volume volume26
Issue issue2
Start Page 25
End Page 41
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002308015
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 10.18926/15395
FullText URL Mem_Fac_Eng_OU_27_1_65.pdf
Author Nara, Shigetoshi| Hara Yuji| Totsuji, Hiroo|
Abstract Quantum mechnical electron wave transfer between two quantum wires which are weakly coupled via a thin potential barrier is considered. The total electronic states are calculated with both analytical ( no field case ) and numerical methods ( under applied electric fields ). The transfer efficiency is evaluated for several specified cases of geometrical structures, potential barrier heights and the externally applied electric field. Estimated trasfer time is of the order of one picosecond in typical mesoscopic structures. The model in this paper can be used to determine important structure parameters for experiments on electron directional coupler controled by external elctric field.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1992-11-25
Volume volume27
Issue issue1
Start Page 65
End Page 79
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307405
JaLCDOI 10.18926/15396
FullText URL Mem_Fac_Eng_OU_27_1_81.pdf
Author Abe, Hirofumi|
Abstract This paper aims to examine the impact of JR (Japan Railways) Seto Ohashi Line on residential land value. First, the study examines the trends in land value in the area along JR Seto Ohashi Line by applying the area comparison method. The method estimates the effect of JR Seto Ohashi Line on residential land value by comparing land values between the study area and the Okayama Metropolitan Area. Second, the property value method is applied to measure the effect of railroad construction. The effect is estimated with a residential land-value regression, which is calibrated using land value data along the Seto Ohashi Line. Finally, the results are compared with the empirical studies in the Greater Tokyo Region, and various features of the impact of railroad construction on land value are identified.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1992-11-25
Volume volume27
Issue issue1
Start Page 81
End Page 92
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307856
JaLCDOI 10.18926/15392
FullText URL Mem_Fac_Eng_OU_27_1_45.pdf
Author Kagawa, Naoki| Wada, Osami| Hai, Xu| Koga, Ryuji| Sano, Hiroya| Inubushi, Kazuyuki|
Abstract 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1992-11-25
Volume volume27
Issue issue1
Start Page 45
End Page 53
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307877
JaLCDOI 10.18926/15390
FullText URL Mem_Fac_Eng_OU_27_1_27.pdf
Author Hirashima Masao| Inaba, Hideo|
Abstract 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1992-11-25
Volume volume27
Issue issue1
Start Page 27
End Page 32
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307336