JaLCDOI 10.18926/15481
フルテキストURL Mem_Fac_Eng_OU_24_1_81.pdf
著者 和田 修己|
抄録 Are calculated the radiation characteristics of two types of primary-feed waveguides of millimeter wave quasi-optical antennas, which transform circular TE(On) mode into a linearly polarized beam. These antennas are utilized for heating and diagnostics of fusion plasma. Analysis is based on the Huygens-Fresnel principle, which takes the diffraction effect into account. For Convenience in analysis, a feed waveguide is divided into two sections, an uniform waveguide section and a visor section. Assuming that the diameter of the waveguide is several times as large as the wavelength and that the structure of the visor is open, the radiation field is approximated by superposition of direct radiation, and first and second reflection on the visor. Numerical results are presented and compared with experimental results. In these types of waveguides, the shadow section on the visor has a great influence on the radiation field. The results of calculation show that the length of the visor should be longer than that obtained by the geometrical optics, and the longer visor reduces the side-lobe level in the direction of the waveguide axis. The results agree well with those in experiments.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1989-11-29
24巻
1号
開始ページ 81
終了ページ 92
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307974
JaLCDOI 10.18926/15482
フルテキストURL Mem_Fac_Eng_OU_24_1_93.pdf
著者 東辻 浩夫| 畑谷 光輝|
抄録 Propagation of charged carriers in semiconductor superlattices is analyzed on the basis of the effective mass approximation with appropriate boundary conditions at heterojunctions taken into account. Applying the finite element method, clarified are the effects of details of the potential profile, such as linear and smooth gradings and random fluctuations, on characteristics of superlattices which are expected to work as collector barriers and energy filters in electronic devices.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1989-11-29
24巻
1号
開始ページ 93
終了ページ 105
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307513
JaLCDOI 10.18926/15483
フルテキストURL Mem_Fac_Eng_OU_24_1_107.pdf
著者 河野 伊一郎| 西垣 誠| 竹下 祐二|
抄録 The numerical feasibility of determining soil water retention and hydraulic conductivity functions simultaneously from one-dimensional transient flow experiments in the laboratory by parameter estimation method is evaluated. Soil hydraulic properties are assumed to be represented by van Genuchten's closed-form expressions involving two unknown parameters: coefficients α and n . These parameters are evaluated by nonlinear least-squares fitting of predicted and observed pressure head with time. Gravity drainage experiments are performed for Toyoura standard sand to evaluate the adequacy of this proposed method.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1989-11-29
24巻
1号
開始ページ 107
終了ページ 114
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307749
JaLCDOI 10.18926/15484
フルテキストURL Mem_Fac_Eng_OU_25_1_15.pdf
著者 榊原 精| Kanadani, Teruto|
抄録 Aging of Al-lmass % Ag alloy at 273K after quenching under various conditions was studied by measurement of electrical resistivity. Scattering of the quasi-equilibrium value of resistivity (p(e)) was not random but closely related to the as-quenched value (p(o)); P(e) increased with increasing p(o)' When the quenching temperature (T(q)) was lower than or equal to 773K, the state at p(e) was controlled substantially by the concentration of quenched vacancy. On the other hand, when T(q)>823K, GP zones formed during quenching played an important role, instead of quenched vacancies, in determining the state.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1990-12-14
25巻
1号
開始ページ 15
終了ページ 21
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307255
JaLCDOI 10.18926/15485
フルテキストURL Mem_Fac_Eng_OU_24_1_115.pdf
著者 阿部 宏史| Nogata Mikio|
抄録 The rapid economic growth of Japan in the postwar period has brought about the over-concentration of activities in a few large cities, and local regions have been losing their economic vitality due to the regional differentials and the population loss. Regional development planning in Japan has sought to achieve a balanced growth of the nation through the development of industries in local regions. This paper aims to examine the regional structure of manufacturing industries in the postwar period and to identify its current problems. Three methods, namely the analysis of coefficient of variation, the rateshare analysis and the shift-share analysis are applied using employment data of manufacturing industries for the years 1955 to 1985. Findings show that while the employment of manufacturing industries has been markedly decentralized from metropolitan to local regions, the disparities in growth rates still exist among regions.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1989-11-29
24巻
1号
開始ページ 115
終了ページ 133
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307659
JaLCDOI 10.18926/15486
フルテキストURL Mem_Fac_Eng_OU_25_1_23.pdf
著者 三浦 嘉也| 高田 潤| 尾坂 明義| 河村 利夫|
抄録 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.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1990-12-14
25巻
1号
開始ページ 23
終了ページ 35
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307600
JaLCDOI 10.18926/15487
フルテキストURL Mem_Fac_Eng_OU_24_1_135.pdf
著者 谷口 健男| 末次 剛| Iwasaki Masaki|
抄録 This paper describes the numerical simulation method of the multi-crack propagation behaviour which appear in a part of civil engineering structures with complex geometrical configuration like steel bridges. Proposed method can treat the interaction of several cracks which locate in a short distance each other, and the process of their growth can be grasped. The method is based on the finite element method, and the linear fracture mechanics is assumed. Proposed method includes following tools for the simulation of the crack propagation behaviour: Automatic Mesh Generators for 3-D, 2-D structural analysis, and 2-D crack propagation analysis, Multi-level Structural Analysis Technique, Estimation Method of the crack growth and the angle of cracks and the modelling method of traffic loadings. The validity of the method is investigated by comparing the result to the experimental one.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1989-11-29
24巻
1号
開始ページ 135
終了ページ 152
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307854
JaLCDOI 10.18926/15488
フルテキストURL Mem_Fac_Eng_OU_25_1_37.pdf
著者 Bouzidi, Moncef| 古賀 隆治| 和田 修己| 香川 直己| Hai, Xu| 小坂 恵| Sano, Hiroya|
抄録 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.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1990-12-14
25巻
1号
開始ページ 37
終了ページ 50
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307549
JaLCDOI 10.18926/15489
フルテキストURL Mem_Fac_Eng_OU_24_2_1.pdf
著者 Umemoto, Masayuki| 竹元 嘉利| 榊原 精| 飛田 守孝|
抄録 Fine particles of Ti-Mo alloy were prepared by evaporation. When Ti-40at % Mo alloy was evaporated on tungsten filament, fine particles of Ti contaminated with W were obtained. These particles were polyhedron in shape and 10~250nm in diameter. Average diameter and size distribution increased with pressure of argon gas (100~600 Torr). When pure Ti was placed on the Mo filament and evaporated from melt down of heated Mo filament in helium gas, fine particles of pure Ti and of Ti-Mo alloy were obtained. In this case, Ti particles were of indeterminate form and of several tens nm in diameter, and their diffraction pattern was of common α-Ti. On the other hand, composition of the Ti-Mo particles was determined to be 18at % Mo by an analysis of EDX. Structure of Ti-Mo particles could not be determined because their diameters were more than 600nm. The temperature of Mo filament, for the most part, was about 1800℃, and there pure Ti particles were produced. The temperature of the fused part of the filament was locally higher than 2600℃, and there Ti-Mo particles were produced. Fine structures of contact region among some Ti particles were observed with HRTEM.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1990-03-29
24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 120002307765
JaLCDOI 10.18926/15490
フルテキストURL Mem_Fac_Eng_OU_25_1_51.pdf
著者 東辻 浩夫|
抄録 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.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1990-12-14
25巻
1号
開始ページ 51
終了ページ 57
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307188
JaLCDOI 10.18926/15491
フルテキストURL Mem_Fac_Eng_OU_24_2_11.pdf
著者 榊原 精| Kanadani, Teruto|
抄録 Aging behavior of Al-0.23mass % Si alloy was studied by measurements of elecrical resistivity. Resistvity maximum was observed in the aging curves at 273K after quenching from various temperatures. Appearance of maximum and its dependence on the quenching temperature were attributed to the formation of GP zones. Even in a more dilute alloy as 0.01mass % Si, the maximum of resistivity was also recognized.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1990-03-29
24巻
2号
開始ページ 11
終了ページ 16
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307615
JaLCDOI 10.18926/15492
フルテキストURL Mem_Fac_Eng_OU_25_1_59.pdf
著者 河野 伊一郎| 西垣 誠| Okada Junji|
抄録 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.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1990-12-14
25巻
1号
開始ページ 59
終了ページ 69
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307472
JaLCDOI 10.18926/15493
フルテキストURL Mem_Fac_Eng_OU_24_2_17.pdf
著者 小西 忠孝| 馬場 充|
抄録 Pressure distribution has been measured and analyzed to clarify the fundamental characteristics of "continuous oil-film" formed in a transparent journal bearing, into which oil in general use is supplied. Measured pressure mostly shows quasi-Sommerfeld distribution, which is characterized by downstream shift of pressure profile and underdevelopment of pressure trough compared with Sommerfeld distribution for perfect oil-film. Sommerfeld distribution is approximately observed only under limited conditions : low eccentricity and low speed. Quasi-Sommerfeld state is rather common in "continuous oil-film", unruptured film formed by using practical lubricants, than Sommerfeld state. Continuous oil-film is accompanied by fine bubbles and is controlled by the growing up or down of the bubbles.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1990-03-29
24巻
2号
開始ページ 17
終了ページ 30
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307431
JaLCDOI 10.18926/15494
フルテキストURL Mem_Fac_Eng_OU_25_1_71.pdf
著者 Myojin Sho| Yamada Masahito| Fujii Naoto|
抄録 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.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1990-12-14
25巻
1号
開始ページ 71
終了ページ 87
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307618
JaLCDOI 10.18926/15495
フルテキストURL Mem_Fac_Eng_OU_24_2_31.pdf
著者 岡 久雄| Isayama Yoshiharu| Nakauchi Makoto| 山本 辰馬|
抄録 A small vibration on the body surface is expected to apply to a clinical examination of the autonomic nervous system. The vibration cannot be found by the naked eyes. It is called a microvibration (MV) or a minor tremor (MT). It is not cleared out why and how the MV occurs, but many papers about its occurrence and clinical application have been published. In this study, the typical spectrum of MV and the various causes of MV occurrence are studied. The relationships of MV with heart rate, muscle contraction and MV are discussed. The power spectrum of MV is obtained by using an autoregressive model.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1990-03-29
24巻
2号
開始ページ 31
終了ページ 40
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307725
JaLCDOI 10.18926/15496
フルテキストURL Mem_Fac_Eng_OU_25_1_89.pdf
著者 阿部 宏史| Oishi Manabu|
抄録 Multidimensional scaling (MDS) has been used in a wide variety of research fields; psychology, political science, anthropology, marketing research, urban and regional planning, and so on. In practical terms, MDS is a statistical method to make a picture of the information in the data. It enables us to examine the "hidden structure" of a set of data. When the set of data is large, MDS is extremely useful, since it is easier and more informative to look at a picture than the data themselves. In this paper, MDS is applied to the interregional migration data of Japanese regions for the years 1960-85. Findings show that the two-dimensional configuration of regions estimated by MDS generally corresponds with the geographical locations of regions, and the structure of interregional migration was very stable over the study years 1960-85. It is also suggested that MDS is a useful tool to identify the relationships between regions using the spatial interaction data.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1990-12-14
25巻
1号
開始ページ 89
終了ページ 98
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307404
JaLCDOI 10.18926/15497
フルテキストURL Mem_Fac_Eng_OU_24_2_41.pdf
著者 東辻 浩夫|
抄録 A possibility to control the microscopic superconducting channel based on the proximity effect is theoretically shown by a simple one-dimensional analysis of de Gennes' equation for the order parameter.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1990-03-29
24巻
2号
開始ページ 41
終了ページ 47
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307289
JaLCDOI 10.18926/15498
フルテキストURL Mem_Fac_Eng_OU_25_1_99.pdf
著者 西垣 誠| 竹下 祐二| 河野 伊一郎|
抄録 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.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1990-12-14
25巻
1号
開始ページ 99
終了ページ 109
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307452
JaLCDOI 10.18926/15499
フルテキストURL Mem_Fac_Eng_OU_24_2_49.pdf
著者 森 忠次| Machida Ken-ichi|
抄録 Distance measurements have been more and more easy and accurate to carry out, and it is expected that distance mesurements may provide rather accurate results than angle measurements. Under these circumstances, caracteritics of errors in typical trilateration nets are investigated. The nets investigated are as follows: From single row of chains to pranimetrically extended nets in figure, open and closed networks with respect to external constraint, and with and without as to internal constraint. Computations are performed by use of the method of condition equations, and behaviours of error propagation and errors of coordinates of stations in the nets are shown in case of typical nets. For example, effects for decrease in error by composing a double row of chains and by enforcing external constraints are explained.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1990-03-29
24巻
2号
開始ページ 49
終了ページ 65
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307544
JaLCDOI 10.18926/15500
フルテキストURL Mem_Fac_Eng_OU_25_2_1.pdf
著者 Okada, Hiroyuki| 飛田 守孝| 榊原 精| 竹元 嘉利|
抄録 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.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1991-03-28
25巻
2号
開始ページ 1
終了ページ 8
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307559