result 8971 件
| 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 | English |
| File Version | publisher |
| NAID | 120002307685 |
| 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 | 10.18926/15503 |
|---|---|
| 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 | English |
| File Version | publisher |
| NAID | 120002307429 |
| 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 | 10.18926/15501 |
|---|---|
| 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 | 10.18926/15500 |
|---|---|
| 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 | English |
| File Version | publisher |
| NAID | 120002307559 |
| 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 | 10.18926/15498 |
|---|---|
| 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 | English |
| File Version | publisher |
| NAID | 120002307452 |
| 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 | 10.18926/15496 |
|---|---|
| FullText URL | Mem_Fac_Eng_OU_25_1_89.pdf |
| Author | Abe, Hirofumi| Oishi Manabu| |
| Abstract | 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. |
| Publication Title | Memoirs of the Faculty of Engineering, Okayama University |
| Published Date | 1990-12-14 |
| Volume | volume25 |
| Issue | issue1 |
| Start Page | 89 |
| End Page | 98 |
| ISSN | 0475-0071 |
| language | English |
| File Version | publisher |
| NAID | 120002307404 |
| 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 | 10.18926/15494 |
|---|---|
| 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 | 10.18926/15493 |
|---|---|
| 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 | 10.18926/15492 |
|---|---|
| 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 | English |
| File Version | publisher |
| NAID | 120002307472 |
| 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 | 10.18926/15490 |
|---|---|
| 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 | English |
| File Version | publisher |
| NAID | 120002307188 |
| 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 | 10.18926/15488 |
|---|---|
| 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 | English |
| File Version | publisher |
| NAID | 120002307549 |
| JaLCDOI | 10.18926/15487 |
|---|---|
| FullText URL | Mem_Fac_Eng_OU_24_1_135.pdf |
| Author | Taniguhi, Takeo| Suetsugu, Tsuyoshi| Iwasaki Masaki| |
| Abstract | 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. |
| Publication Title | Memoirs of the Faculty of Engineering, Okayama University |
| Published Date | 1989-11-29 |
| Volume | volume24 |
| Issue | issue1 |
| Start Page | 135 |
| End Page | 152 |
| ISSN | 0475-0071 |
| language | English |
| File Version | publisher |
| NAID | 120002307854 |
| 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 |
