| 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 | 10.18926/15470 |
|---|---|
| FullText URL | Mem_Fac_Eng_OU_24_1_13.pdf |
| Author | Uno, Yoshiyuki| Nakajima, Toshikatsu| Endo, Osamu| |
| Abstract | The generation mechanism of crater in electrical discharge machining is analyzed with a single pulse discharge device for alloy tool steel, black alumina ceramics, cermet and cemented carbide, investigating the gap voltage, the discharge current, the shape of crater, the wear of electrode and so on. The experimental analysis makes it clear that the shape of crater has a characteristic feature for the kind of workpiece. The shape of electrode, which changes with the wear by an electric spark, has a significant effect on the shape of crater. The diameter and the depth of crater have a close relation to the discharge energy for alloy tool steel, black alumina ceramics and cermet, while those for cemented carbide are related to the discharge current. The shape factor which is the ratio of the depth to the diameter of crater is different for the work material. |
| Publication Title | Memoirs of the Faculty of Engineering, Okayama University |
| Published Date | 1989-11-29 |
| Volume | volume24 |
| Issue | issue1 |
| Start Page | 13 |
| End Page | 24 |
| ISSN | 0475-0071 |
| language | English |
| File Version | publisher |
| NAID | 120002307269 |
| JaLCDOI | 10.18926/15471 |
|---|---|
| FullText URL | Mem_Fac_Eng_OU_24_1_25.pdf |
| Author | Kajihara, Yasuhiro| Osaki, Hirokazu| |
| Abstract | An expert system, in which preconditions and rules are expressed in logical formulas, is developed to support the scheduling of an automated job shop type multi-item assembly line. This system has the foIIowing characteristics to apply any case of schedulings: (1)Forward scheduling orbackward scheduling can be made. (2)The criterion on the input order of products, the dispatching process at each assembly station, and the selection of products from a buffer can be selected from several priority criteria. (3)Layout, number and velocity of vehicles, and the capacity of each buffer can be changed. |
| Publication Title | Memoirs of the Faculty of Engineering, Okayama University |
| Published Date | 1989-11-29 |
| Volume | volume24 |
| Issue | issue1 |
| Start Page | 25 |
| End Page | 39 |
| ISSN | 0475-0071 |
| language | English |
| File Version | publisher |
| NAID | 120002307454 |
| JaLCDOI | 10.18926/15482 |
|---|---|
| FullText URL | Mem_Fac_Eng_OU_24_1_93.pdf |
| Author | Totsuji, Hiroo| Hatatani, Teruki| |
| Abstract | 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. |
| Publication Title | Memoirs of the Faculty of Engineering, Okayama University |
| Published Date | 1989-11-29 |
| Volume | volume24 |
| Issue | issue1 |
| Start Page | 93 |
| End Page | 105 |
| ISSN | 0475-0071 |
| language | English |
| File Version | publisher |
| NAID | 120002307513 |
| JaLCDOI | 10.18926/15483 |
|---|---|
| FullText URL | Mem_Fac_Eng_OU_24_1_107.pdf |
| Author | Kohno, Iichiro| Nishigaki, Makoto| Takeshita, Yuji| |
| Abstract | 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. |
| Publication Title | Memoirs of the Faculty of Engineering, Okayama University |
| Published Date | 1989-11-29 |
| Volume | volume24 |
| Issue | issue1 |
| Start Page | 107 |
| End Page | 114 |
| ISSN | 0475-0071 |
| language | English |
| File Version | publisher |
| NAID | 120002307749 |
| JaLCDOI | 10.18926/15479 |
|---|---|
| FullText URL | Mem_Fac_Eng_OU_24_1_73.pdf |
| Author | Oka, Hisao| Isayama Yoshiharu| Yamamoto, Yoshitake| Yamamoto, Tatsuma| |
| Abstract | There is a small vibration which goes undetected by the naked eyes. It is called a microvibration (MV) or a minor tremor (MT). The MV on the body surface is expected to apply to a clinical examination of the autonomic nervous system. It is not cleared why and how the MV occurs, but there are many papers about its occurrence and clinical application. In this study, MV measuring system, its estimation and basic characteristics are examined. The difference between head MV and thenar MV, individual MV and diurnal and seasonal change are discussed. The power spectrum of MV is obtained using an autoregressive model. |
| Publication Title | Memoirs of the Faculty of Engineering, Okayama University |
| Published Date | 1989-11-29 |
| Volume | volume24 |
| Issue | issue1 |
| Start Page | 73 |
| End Page | 80 |
| ISSN | 0475-0071 |
| language | English |
| File Version | publisher |
| NAID | 120002307633 |
| JaLCDOI | 10.18926/15481 |
|---|---|
| FullText URL | Mem_Fac_Eng_OU_24_1_81.pdf |
| Author | Wada, Osami| |
| Abstract | 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. |
| Publication Title | Memoirs of the Faculty of Engineering, Okayama University |
| Published Date | 1989-11-29 |
| Volume | volume24 |
| Issue | issue1 |
| Start Page | 81 |
| End Page | 92 |
| ISSN | 0475-0071 |
| language | English |
| File Version | publisher |
| NAID | 120002307974 |
| JaLCDOI | 10.18926/15495 |
|---|---|
| FullText URL | Mem_Fac_Eng_OU_24_2_31.pdf |
| Author | Oka, Hisao| Isayama Yoshiharu| Nakauchi Makoto| Yamamoto, Tatsuma| |
| Abstract | 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. |
| Publication Title | Memoirs of the Faculty of Engineering, Okayama University |
| Published Date | 1990-03-29 |
| Volume | volume24 |
| Issue | issue2 |
| Start Page | 31 |
| End Page | 40 |
| ISSN | 0475-0071 |
| language | English |
| File Version | publisher |
| NAID | 120002307725 |
| JaLCDOI | 10.18926/15507 |
|---|---|
| FullText URL | Mem_Fac_Eng_OU_24_2_99.pdf |
| Author | Taniguchi, Takeo| Fujiwara Kohji| |
| Abstract | This paper presents an effective solver for a large sparse set of linear algebraic equations, which appears at the application of the finite element and the finite difference methods in engineering field. Proposed method is a family of SKYLINE METHOD, and for faster computation on the vector processors the original skyline is modified with respect to following three items; the use of inner products of matrix operations, the removal of unnecessary numerical operations and the introduction of two-dimensional array for storing the data of coefficient matrix. |
| Publication Title | Memoirs of the Faculty of Engineering, Okayama University |
| Published Date | 1990-03-29 |
| Volume | volume24 |
| Issue | issue2 |
| Start Page | 99 |
| End Page | 112 |
| ISSN | 0475-0071 |
| language | English |
| File Version | publisher |
| NAID | 120002307515 |
| JaLCDOI | 10.18926/15505 |
|---|---|
| FullText URL | Mem_Fac_Eng_OU_24_2_89.pdf |
| Author | Yokohira, Tokumi| |
| Abstract | This paper considers a test set for an ALU with look ahead carry generators(LCGs). The ALU is logically partitioned into two groups of blocks, the group of one-bit operation units and LCG group. Each group is tested in parallel and exhaustively, independent of the other. And an easily testable design is applied to several blocks for decreasing the number of the input combinations of them. Under the easily testable design, a minimum test set for each group is generated, and the upper and lower bounds for a minimum test for the ALU are derived. The difference of the lower and upper bounds is not large, and a test set whose number of test vectors is equal to the upper bound can be easily obtained as the union of minimum test sets for two groups. Hence, the union can be used as a complete and practical test set for the ALU. |
| Publication Title | Memoirs of the Faculty of Engineering, Okayama University |
| Published Date | 1990-03-29 |
| Volume | volume24 |
| Issue | issue2 |
| Start Page | 89 |
| End Page | 98 |
| ISSN | 0475-0071 |
| language | English |
| File Version | publisher |
| NAID | 120002307212 |
| JaLCDOI | 10.18926/15491 |
|---|---|
| FullText URL | Mem_Fac_Eng_OU_24_2_11.pdf |
| Author | Sakakibara, Akira| Kanadani, Teruto| |
| Abstract | 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. |
| Publication Title | Memoirs of the Faculty of Engineering, Okayama University |
| Published Date | 1990-03-29 |
| Volume | volume24 |
| Issue | issue2 |
| Start Page | 11 |
| End Page | 16 |
| ISSN | 0475-0071 |
| language | English |
| File Version | publisher |
| NAID | 120002307615 |
| JaLCDOI | 10.18926/15501 |
|---|---|
| FullText URL | Mem_Fac_Eng_OU_24_2_67.pdf |
| Author | Nago, Hiroshi| Maeno, Shiro| |
| Abstract | Many hydraulic structures are damaged by under flood flow and storm waves year after year. Many cases of dike and breakwater failure are caused by the suck out of sand from behind the revetment. This type of failure will be in close relation to the dynamic behavior of sand bed around the revetment. In this paper, from this point of view, we investigated the basic characteristics of such sand movement by small model tests and tried to explain the hydro- and soil-mechanical mechanism of this phenomenon theoretically. |
| Publication Title | Memoirs of the Faculty of Engineering, Okayama University |
| Published Date | 1990-03-29 |
| Volume | volume24 |
| Issue | issue2 |
| Start Page | 67 |
| End Page | 78 |
| ISSN | 0475-0071 |
| language | English |
| File Version | publisher |
| NAID | 120002307928 |
| JaLCDOI | 10.18926/15493 |
|---|---|
| FullText URL | Mem_Fac_Eng_OU_24_2_17.pdf |
| Author | Konishi, Tadataka| Baba, Mitsuru| |
| Abstract | 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. |
| Publication Title | Memoirs of the Faculty of Engineering, Okayama University |
| Published Date | 1990-03-29 |
| Volume | volume24 |
| Issue | issue2 |
| Start Page | 17 |
| End Page | 30 |
| ISSN | 0475-0071 |
| language | English |
| File Version | publisher |
| NAID | 120002307431 |
| JaLCDOI | 10.18926/15489 |
|---|---|
| FullText URL | Mem_Fac_Eng_OU_24_2_1.pdf |
| Author | Umemoto, Masayuki| Takemoto, Yoshito| Sakakibara, Akira| Hida, Moritaka| |
| Abstract | 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. |
| Publication Title | Memoirs of the Faculty of Engineering, Okayama University |
| Published Date | 1990-03-29 |
| Volume | volume24 |
| Issue | issue2 |
| Start Page | 1 |
| End Page | 9 |
| ISSN | 0475-0071 |
| language | English |
| File Version | publisher |
| NAID | 120002307765 |
| JaLCDOI | 10.18926/15497 |
|---|---|
| FullText URL | Mem_Fac_Eng_OU_24_2_41.pdf |
| Author | Totsuji, Hiroo| |
| Abstract | 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. |
| Publication Title | Memoirs of the Faculty of Engineering, Okayama University |
| Published Date | 1990-03-29 |
| Volume | volume24 |
| Issue | issue2 |
| Start Page | 41 |
| End Page | 47 |
| ISSN | 0475-0071 |
| language | English |
| File Version | publisher |
| NAID | 120002307289 |
| JaLCDOI | 10.18926/15499 |
|---|---|
| FullText URL | Mem_Fac_Eng_OU_24_2_49.pdf |
| Author | Mori, Chuji| Machida Ken-ichi| |
| Abstract | 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. |
| Publication Title | Memoirs of the Faculty of Engineering, Okayama University |
| Published Date | 1990-03-29 |
| Volume | volume24 |
| Issue | issue2 |
| Start Page | 49 |
| End Page | 65 |
| ISSN | 0475-0071 |
| language | English |
| File Version | publisher |
| NAID | 120002307544 |
| JaLCDOI | 10.18926/15502 |
|---|---|
| FullText URL | Mem_Fac_Eng_OU_24_2_79.pdf |
| Author | Sato, Yoichiro| |
| Abstract | In asynchronous arbiters, failures may happen, caused by metastable operations. The purpose of this study is to derive a formula to estimate such failures in a ring arbiter as mean time between failures (MTBF), under the condition that incidences of requests issued in all devices are different from each other. The operation of the arbiter is formularized by a markov chain. This chain is used to decide the probability at which each of possible failures contributes to MTBF. The sum of such probabilities gives the MTBF which can be represented as a sum of a finite number of terms. As an example, MTBF of a ring arbiter composed of 3 cells is shown. |
| Publication Title | Memoirs of the Faculty of Engineering, Okayama University |
| Published Date | 1990-03-29 |
| Volume | volume24 |
| Issue | issue2 |
| Start Page | 79 |
| End Page | 87 |
| ISSN | 0475-0071 |
| language | English |
| File Version | publisher |
| NAID | 120002307486 |
| 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 | English |
| File Version | publisher |
| NAID | 120002307600 |
| 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 | English |
| File Version | publisher |
| NAID | 120002307618 |
| JaLCDOI | 10.18926/15484 |
|---|---|
| FullText URL | Mem_Fac_Eng_OU_25_1_15.pdf |
| Author | Sakakibara, Akira| Kanadani, Teruto| |
| Abstract | 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. |
| Publication Title | Memoirs of the Faculty of Engineering, Okayama University |
| Published Date | 1990-12-14 |
| Volume | volume25 |
| Issue | issue1 |
| Start Page | 15 |
| End Page | 21 |
| ISSN | 0475-0071 |
| language | English |
| File Version | publisher |
| NAID | 120002307255 |
