| JaLCDOI | 10.18926/15803 |
|---|---|
| FullText URL | Mem_Sch_Eng_OU_16_1_147.pdf |
| Author | Taniguchi Takeo| |
| Abstract | Renumbering algorithms commonly in use for the band solver are generally applicable for any kind of linear equations, and, therefore, we may say that they cann't effectively utilize the characteristics of the finite element mesh. In this paper we investigate the characteristics of the finite element mesh systems, and introduce them into Taniguchi-Shiraishi Algorithm which already introduced some properties of FEM mesh systems. And through several numerical experiments it is proved that this improved algorithm is one of the fastest one. |
| Publication Title | Memoirs of the School of Engineering, Okayama University |
| Published Date | 1982-03-01 |
| Volume | volume16 |
| Issue | issue1 |
| Start Page | 147 |
| End Page | 159 |
| ISSN | 0475-0071 |
| language | English |
| File Version | publisher |
| NAID | 120002307533 |
| JaLCDOI | 10.18926/15801 |
|---|---|
| FullText URL | Mem_Sch_Eng_OU_16_1_125.pdf |
| Author | Inouye Hiroshi| Oda Shinji| |
| Abstract | A system dynamics model to forecast future movements of a city was studied. The model consists of three sections of population sector, industry sector, land use sector and some divisions of labor, income employment, housing land which connect each sections. Economic growth rate, public investment program, housing land supply program were incorporated in the model as political variables. The model was applied to Okayama city for thirty years from 1975 to 2005. The results of the simulation are summarized as follows: 1) The drift of peoples into Okayama city will advance in the future. 2) Tertiary industries will be given much weight as compared with secondary industries. 3) Because of the drift of peoples, housing problems will be serious in the future. |
| Publication Title | Memoirs of the School of Engineering, Okayama University |
| Published Date | 1982-03-01 |
| Volume | volume16 |
| Issue | issue1 |
| Start Page | 125 |
| End Page | 145 |
| ISSN | 0475-0071 |
| language | English |
| File Version | publisher |
| NAID | 120002308014 |
| JaLCDOI | 10.18926/15799 |
|---|---|
| FullText URL | Mem_Sch_Eng_OU_16_1_105.pdf |
| Author | Myojin Sho| Asai Kazuhiko| |
| Abstract | A welfare economic approach is tried to an optimal decision of toll rate and expansion of urban expressway network in an equilibrium of toll revenues and cost of service supplied. The model, originated with Yamada, is such that the decision comes into optimality when the maximum consumers' surplus is reached in the equilibrium condition. The paper is concerned with some general aspects of the optimal solution and reexamination of the solution obtained in the past when used a specific demand curve. General aspects obtained are as follows; The extremum condition to consumers' surplus is equivalent to that to diverted traffic (the realized number of expressway users) only when demand curve has such a property that the marginal consumers' surplus to network expansion vanishes. In case that the marginal consumers' surplus does not vanish, the extrema of consumers' surplus is found in the regions of negative marginal diverted traffic if demand curve yields positive marginal surplus, and in the regions of the positive if it gives negative marginal surplus. The contact points of demand and average cost curves give extrema of neither consumers' surplus nor diverted traffic. An implicative finding, made out by Yamada by using a specific demand curve, that optimal network expansion is reached when the marginal service cost to expansion averaged to the marginal diverted traffic to expansion is equal to the value of time saved by using expressway just by mean trip length holds good at the points of the maximum diverted traffic, but not at the contacts of demand and average cost curves. In case of the demand curve, the condition for an equilibrium of revenues and cost to come into existence is that the minimum of the ratio of service cost averaged to the whole population of expressway users to the value of time mentioned above is less than or equal to e(-1). |
| Publication Title | Memoirs of the School of Engineering, Okayama University |
| Published Date | 1982-03-01 |
| Volume | volume16 |
| Issue | issue1 |
| Start Page | 105 |
| End Page | 123 |
| ISSN | 0475-0071 |
| language | English |
| File Version | publisher |
| NAID | 120002307932 |
| JaLCDOI | 10.18926/15797 |
|---|---|
| FullText URL | Mem_Sch_Eng_OU_16_1_91.pdf |
| Author | Nago Hiroshi| |
| Abstract | In this paper the vertical distribution of pore water pressure in the highly saturated sand layer under the oscillating water pressure are treated theoretically and experimentally. By the experiments it is shown that the water pressure acting on the sand surface propagates into the sand layer with the damping in amplitude and the lag in phase, and that the liquefaction, the state that the effective stress becomes zero, occurs under certain conditions. These experimental results are explained fairly well by the same theoretical treatment as for the ground water problems in the elastic aquifer. The main characteristics of liquefaction clarified by the analysis are as follows. 1) The depth of the liquified layer increases with the increase of the amplitude and the frequency of the oscillating water pressure. 2) The increase of the volume of the water and the air in the layer increases the liquified depth. Especially the very small amount of the air affects the liquefaction significantly. 3) The liquified depth decrease rapidly with the increase of the compressibility coefficient of the sand. 4) In the range beyond a certain value of the permeability coefficient the liquified depth decrease with the increase of the coefficient. |
| Publication Title | Memoirs of the School of Engineering, Okayama University |
| Published Date | 1982-03-01 |
| Volume | volume16 |
| Issue | issue1 |
| Start Page | 91 |
| End Page | 104 |
| ISSN | 0475-0071 |
| language | English |
| File Version | publisher |
| NAID | 120002307671 |
| JaLCDOI | 10.18926/15795 |
|---|---|
| FullText URL | Mem_Sch_Eng_OU_16_1_65.pdf |
| Author | Kohno Iichiro| Nishigaki Makoto| |
| Abstract | The purposes of this research is an investigation of the intrusion of sea water into coastal aquifers. For this subject, this paper deals with proposing rational methods of getting diffusion coefficient and dispersion parameter for flow in porous media in a laboratory. These parameters of soil are indispensable in order to apply an analytical approach or a numerical approach to actual salt water intrusion problems. Experimental apparatuses were constructed and test procedures were also developed to measure concentration behaviors in a saturated porous media by using electro conductivity probe. As the results, the diffusion coefficients for the Toyoura standard sand and the Asahi river sand determined by two methods, that is, "Boltzman's transformation method" and "Instantaneous profile analysis method". The longitudinal coefficient of dispersion for one-dimensional flow was also determined by the least squares curve fitting method with a function of a certain range of seepage velocity. |
| Publication Title | Memoirs of the School of Engineering, Okayama University |
| Published Date | 1982-03-01 |
| Volume | volume16 |
| Issue | issue1 |
| Start Page | 65 |
| End Page | 89 |
| ISSN | 0475-0071 |
| language | English |
| File Version | publisher |
| NAID | 120002307205 |
| JaLCDOI | 10.18926/15793 |
|---|---|
| FullText URL | Mem_Sch_Eng_OU_16_1_47.pdf |
| Author | Mori Chuji| Hattori Susumu| Tanabe Hiroshi| |
| Abstract | A practical example of digital rectification of tilted photographs using a drum scanning micro densitometer and general purpose computers is depicted. The present research covers rectification of projective distorsions, occuring when the camera axis is not truly vertical, and affine distorsions due to curvature of a drum of a scanner. For this purpose, fundamental mathematical expressions were derived. And some pixel interpolation methods necessary for image reconstruction were compared experimentally. The examples revealed, however, that the film was deformed so complexly that they could not be corrected sufficiently only by affine transformation. Accuracy of rectification was checked by use of stereo aerial photographs in terms of residual y-parallaxes. The result showed residual y-parallaxes of ± 1 pixel (± 50 μm) and sometimes ± 2 pixels were observed. They seem to be caused mainly by film deformations which have not been eliminated, and their amount seems to exceed the photogrammetric tolerance. |
| Publication Title | Memoirs of the School of Engineering, Okayama University |
| Published Date | 1982-03-01 |
| Volume | volume16 |
| Issue | issue1 |
| Start Page | 47 |
| End Page | 64 |
| ISSN | 0475-0071 |
| language | English |
| File Version | publisher |
| NAID | 120002307893 |
| JaLCDOI | 10.18926/15791 |
|---|---|
| FullText URL | Mem_Sch_Eng_OU_16_1_31.pdf |
| Author | Kaneda Masahiro| Akahori Ichiro| |
| Abstract | System data handling in CAD sY8tem for designing control systems is discussed. A man-oriented data description method for a wide sense block diagram and its automatical transformation into the state space description is proposed. This work is a part of CAD system: CADPACS-T which has been under development for designing control systems in our laboratory. The proposal data description for a wide sense block diagram has the following features: 1) to correspond nicety to the block diagram and to be suitable for a man-oriented expression, 2) to express even a large scale system compactly by partitioning into some subsystems defined externally, 3) to be easy to add /or alter the input-output terminals, parameters or elements, and 4) to need not to assign the connection relationship explicitly owing to adopting the input-output terminal/line names. Moreover, system data handling in designing the PI controller for an actual boiler system expressed in a block diagram is taken up as an example. |
| Publication Title | Memoirs of the School of Engineering, Okayama University |
| Published Date | 1982-03-01 |
| Volume | volume16 |
| Issue | issue1 |
| Start Page | 31 |
| End Page | 45 |
| ISSN | 0475-0071 |
| language | English |
| File Version | publisher |
| NAID | 120002308002 |
| JaLCDOI | 10.18926/15790 |
|---|---|
| FullText URL | Mem_Sch_Eng_OU_16_1_21.pdf |
| Author | Koga, Ryuji| Kosaka, Megumi| Sano, Hiroya| |
| Abstract | In a sensitive spectrometry with lead-salt diode lasers, etalon-fringe phenomena often intervene in the measured absorption spectrum. Derivative methods are employed for the purpose of high resolution where the pertaining wavelength is modulated. This paper presents results of mathematical examination on a possible improvement of immunity from the etalon-fringes by choosing the profile of the wavelength modulation. |
| Publication Title | Memoirs of the School of Engineering, Okayama University |
| Published Date | 1982-03-01 |
| Volume | volume16 |
| Issue | issue1 |
| Start Page | 21 |
| End Page | 30 |
| ISSN | 0475-0071 |
| language | English |
| File Version | publisher |
| NAID | 120002307691 |
