| JaLCDOI | 10.18926/15478 |
|---|---|
| FullText URL | Mem_Fac_Eng_OU_23_2_45.pdf |
| Author | Taniguchi, Takeo| Fujiwara, Kohji| |
| Abstract | This paper includes a solver for a large sparse set of linear algebraic equations which are obtained by the application of the finite element method to static structural problems. Proposed method is a modification of Robust Incomplete Choleski-Conjugate Gradient Method, which belongs to Preconditioned Conjugate Gradient Method suitable for supercomputers. Through a number of numerical experiments the authors show that Robust Incomplete Choleski-Conjugate Gradient Method sometimes fails in to obtain the solutions, secondly they clarify the reason of the failures from the theoretical viewpoint, and finally they propose a modification of the robust method by the introduction of the theoretical result. Proposed method is as effective as the original, and it can overcome the demerit of Robust Method which is clarified through numerical experiments. |
| Publication Title | Memoirs of the Faculty of Engineering, Okayama University |
| Published Date | 1989-03-30 |
| Volume | volume23 |
| Issue | issue2 |
| Start Page | 45 |
| End Page | 55 |
| ISSN | 0475-0071 |
| language | 日本語 |
| File Version | publisher |
| NAID | 120002307820 |
| JaLCDOI | 10.18926/15480 |
|---|---|
| FullText URL | Mem_Fac_Eng_OU_25_1_1.pdf |
| Author | Gao Hong| Wada, Tsutomu| Noritsugu, Toshiro| |
| Abstract | How to reduce and simplify the calculation for image recognition is a very attractive and important issue in order to realize the real time control of a robot based on the image recognition results. This paper describes a method of extracting 2 - dimensional geometrical features of cubic objects based on the normal vector distributions from the visual information obtained with the laser range finder to reduce the calculation of the image recognition. In this research a laser beam is scanned in the horizontal plane to which the cubic objects stand vertically and the laser spot is detected with a TV camera every sampling time. These spots make an intermittent locus which includes some special lines corresponding to the cubic objects. To extract the features of the cubic objects, we utilize the normal vectors formed on the locus. If some normal vectors distribute in the same direction and the origin of the normal vectors are very close to their neighbor's, these normal vectors can be classified into the same class, -the straight line class. Because the normal vectors on the neighbor surfaces of the cubic objects are vertical to each other, we use this property to determine the pair of straight lines which belong to the cubic objects. Making the histogram based on the normal vectors with the same direction, we obtain the peaks which are supported by the points on the cubic object surfaces. Then, the points can be extracted from the set of points on the whole locus inversely according to the relations with the peaks and the features of the cubic object can be extracted by applying method of least square to these extracted points. The experiments proved the availability of the proposed processing algorithm. |
| Publication Title | Memoirs of the Faculty of Engineering, Okayama University |
| Published Date | 1990-12-14 |
| Volume | volume25 |
| Issue | issue1 |
| Start Page | 1 |
| End Page | 13 |
| ISSN | 0475-0071 |
| language | 英語 |
| File Version | publisher |
| NAID | 120002308010 |
| 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 | 英語 |
| File Version | publisher |
| NAID | 120002307974 |
| 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 | 英語 |
| File Version | publisher |
| NAID | 120002307513 |
| 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 | 英語 |
| File Version | publisher |
| NAID | 120002307255 |
| JaLCDOI | 10.18926/15485 |
|---|---|
| FullText URL | Mem_Fac_Eng_OU_24_1_115.pdf |
| Author | Abe, Hirofumi| Nogata Mikio| |
| Abstract | 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. |
| Publication Title | Memoirs of the Faculty of Engineering, Okayama University |
| Published Date | 1989-11-29 |
| Volume | volume24 |
| Issue | issue1 |
| Start Page | 115 |
| End Page | 133 |
| ISSN | 0475-0071 |
| language | 英語 |
| File Version | publisher |
| NAID | 120002307659 |
| 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 | 英語 |
| File Version | publisher |
| NAID | 120002307854 |
| 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 | 英語 |
| File Version | publisher |
| NAID | 120002307188 |
| 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 | 英語 |
| File Version | publisher |
| NAID | 120002307615 |
| 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 | 英語 |
| File Version | publisher |
| NAID | 120002307431 |
| 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 | 英語 |
| File Version | publisher |
| NAID | 120002307618 |
| 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 | 英語 |
| File Version | publisher |
| NAID | 120002307404 |
| 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 | 英語 |
| 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 | 英語 |
| 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 | 英語 |
| File Version | publisher |
| NAID | 120002307486 |
| 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 | 10.18926/15506 |
|---|---|
| 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 | 10.18926/15507 |
|---|---|
| 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 | 英語 |
| File Version | publisher |
| NAID | 120002307515 |
| JaLCDOI | 10.18926/15512 |
|---|---|
| FullText URL | Mem_Fac_Eng_OU_25_2_69.pdf |
| Author | Tsuchiya Takao| Kagawa, Yukio| |
| Abstract | A finite element approach to the calculation of nonlinear sound propagation is proposed. Under the assumption of a weak nonlinearity, a linearized one-dimensional equation is considered. The equation is discretized in space, and is then solved for time by using Newmark-β integration scheme, in which a numerical damping is devised. Some numerical demonstrations are made for the nonlinear sound propagation of a single-shot pulse in air. It is shown that the shock wave propagation is stably and accurately simulated by the introduction of the numerical damping. |
| Publication Title | Memoirs of the Faculty of Engineering, Okayama University |
| Published Date | 1991-03-28 |
| Volume | volume25 |
| Issue | issue2 |
| Start Page | 69 |
| End Page | 80 |
| ISSN | 0475-0071 |
| language | 英語 |
| File Version | publisher |
| NAID | 120002307747 |
| JaLCDOI | 10.18926/15381 |
|---|---|
| FullText URL | Mem_Fac_Eng_OU_30_1_75.pdf |
| Author | Totsuji, Hiroo| Inoue, Yoshihiko| Kishimoto, Tokunari| Totsuji, Chieko| Nara, Shigetoshi| |
| Abstract | Molecular dynamics of the Yukawa system, the system of particles interacting via the Yukawa or the screened Coulomb potential, are formulated for various statistical ensembles and external conditions. The Yukawa potential smoothly interpolates the long-range Coulomb and the short-range interactions by adjusting a single parameter, the screening length. In order to reduce the effect of boundaries, the periodic boundary conditions are imposed and the deformations of the fundamental vectors of periodicity are taken into account. Ewald-type expressions for interaction energy, force, and kinematic pressure are given explicitly. |
| Publication Title | Memoirs of the Faculty of Engineering, Okayama University |
| Published Date | 1995-12-28 |
| Volume | volume30 |
| Issue | issue1 |
| Start Page | 75 |
| End Page | 87 |
| ISSN | 0475-0071 |
| language | 英語 |
| File Version | publisher |
| NAID | 120002307479 |
