JaLCDOI 10.18926/15779
FullText URL Mem_Sch_Eng_OU_15_2_107.pdf
Author Totsuji Hiroo| Obata Takashi| Funahashi Takahiko|
Abstract The dynamic form factor and the transverse part of the fluctuation spectrum of momentum density are analysed on the basis of the generalized Langevin equation. According to the indication of the result, numerical experiments are extended and it is shown that the transverse fluctuation spectrum contains two kinds of excitations. The frequency moment sum rules are discussed in relation to one of these excitations.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1981-03-30
Volume volume15
Issue issue2
Start Page 107
End Page 118
ISSN 0475-0071
language English
File Version publisher
NAID 120002307901
JaLCDOI 10.18926/15778
FullText URL Mem_Sch_Eng_OU_18_1_111.pdf
Author Taniguchi Takeo| Matsumoto Takumi| Mitsuoka Kazuhiko|
Abstract The convergence condition of the explicit difference method for the heat transfer problem is aiready obtained. On the other hand, if the problem is formulated by using the weighted residual method for spatial axis, we have no tool to estimate the critical timestep width. In this paper, the estimation method is theoretically presented, and its propriety is examined through a number of numerical experiments.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1984-03-30
Volume volume18
Issue issue1
Start Page 111
End Page 130
ISSN 0475-0071
language English
File Version publisher
NAID 120002307658
JaLCDOI 10.18926/15777
FullText URL Mem_Sch_Eng_OU_15_2_93.pdf
Author Totsuji Hiroo|
Abstract A method to obtain exact lower bounds for the correlation energy of one-component plasmas is extended to neutral mixtures of charged hard spheres. Upper bounds for the correlation functions of charge densities are derived. These upper bounds, the semi-positivity of correlation functions, and that of the charge-densityfluctuation spectrum are used to improve upon the known bound due to Onsager.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1981-03-30
Volume volume15
Issue issue2
Start Page 93
End Page 106
ISSN 0475-0071
language English
File Version publisher
NAID 120002307165
JaLCDOI 10.18926/15776
FullText URL Mem_Sch_Eng_OU_15_2_79.pdf
Author Koga, Ryuji| Nagase, Satoru| Kosaka, Megumi| Sano, Hiroya|
Abstract A method to monitor atmospheric gas concentration employing a tunable diode laser is proposed. An apparatus was built and experiments were made. The tunable diode laser employed was of'PbSnTe with its wavenumber about 1200 cm(-1) at a temperature of 77 K. Methane concentration in laboratory atmosphere was measured on the experiments. The inquired gas-density is obtained by a hardwired microcomputer incorporating the measured absorption spectrum over a prescribed range instead of an absorption at a single wavenumber. By this, drift type noises are suppressed. After an analysis based on experimental data, an attainable sensitivity for methane was found to be 1 ppb.m. This value may increase if an etalon fringe interference exists. The natural concentration, about 1 ppm, of atmospheric methane was actually measured with a short optical path of only one meter.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1981-03-30
Volume volume15
Issue issue2
Start Page 79
End Page 92
ISSN 0475-0071
language English
File Version publisher
NAID 120002307246
JaLCDOI 10.18926/15775
FullText URL Mem_Sch_Eng_OU_18_1_101.pdf
Author Mori Chuji| Hattori Susumu|
Abstract In stereo matching of images, sample cross-covariances are used commonly as a criterion for deciding whether matched points are truly conjugate. Hereupon window width is a serious parameters to dominate matching stability. This paper argues about relation of matching stability with window width in terms of statistical behavior of sample covariances. For simple circumstances of analysis auto-covariances of a single image are considered instead of cross-covariances of stereo ones. First the mean and variance of sample auto-covariances are derived with parameters, window width and positional lag. Secondly they are evaluated from the correlation function estimated on an aerial image under the assumption of ergodicity to observe how they vary according as two parameters vary. From this result a variation factor is proved usefull to estimate appropriate window width.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1984-03-30
Volume volume18
Issue issue1
Start Page 101
End Page 110
ISSN 0475-0071
language English
File Version publisher
NAID 120002307207
JaLCDOI 10.18926/15774
FullText URL Mem_Sch_Eng_OU_18_1_91.pdf
Author Sano, Hiroya| Koga, Ryuji| Kosaka, Megumi| Wake, Ichiro|
Abstract This paper presents an optical-waveform synthesizer as one of the applications of optical bistable devices. This device is advantageous in terms of faster operation in which width of each pulse obtained is down to the order of subnanosecond, because this device employs both GaAs- and Si-optoelectronic switches as photodetector. Optical pulse shaping as a preliminary experiment is also described.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1984-03-30
Volume volume18
Issue issue1
Start Page 91
End Page 100
ISSN 0475-0071
language English
File Version publisher
NAID 120002307204
JaLCDOI 10.18926/15773
FullText URL Mem_Sch_Eng_OU_15_2_69.pdf
Author Tanada Yoshihiro| Sano Hiroya|
Abstract Electromagnetic impulse noise which is harmful to signal measurement or transmission of information, is smoothed by the orthogonal transform processor. The idealized impulse noise with infinitesimal duration and Gaussianly-distributed amplitude shows the same spectral characteristics as white Gaussian noise. Optimal correlation detector against such noise is easily realized by the orthogonal transform processor. Photoelectric pulse signals disturbed by the impulse noise from the power supply can be well detected through the Walsh waveform analyzer. Also, orthogonally-synthesized signals can be demodulated with firmly-suppressed impulse noise, where both the statistical and instantaneous SNRs are superior to those in the usual PCM transmission system.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1981-03-30
Volume volume15
Issue issue2
Start Page 69
End Page 77
ISSN 0475-0071
language English
File Version publisher
NAID 120002307262
JaLCDOI 10.18926/15772
FullText URL Mem_Sch_Eng_OU_15_2_55.pdf
Author Hida Moritaka| Matsumori Nobuo| Terauchi Hikaru|
Abstract X-ray diffuse scatteing intensity measurement has been carried out for the Al-3,82% Cu single crystal in which GP (2) zones are found. The two dimensional equiintensity contour maps in h(1) h(2) 0 plane are obtained from surveying around several reflections. The diffuse intensity around 2 1 0 reflection, which shows a cross like streak, is carefully examined. Warren-Cowley short-range order parameters, a(i), are estimated from the diffuse intensities around 2 1 0 reflection. The component of the intensities coming from atomic displacements was subtracted from the total diffuse intensity. It is found that the equi-intensity contours after the correction of the atomic displacements shows an anisotropic distribution and the GP(2) zone is an ellipsoid with a modified layer structure.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1981-03-30
Volume volume15
Issue issue2
Start Page 55
End Page 67
ISSN 0475-0071
language English
File Version publisher
NAID 120002307124
JaLCDOI 10.18926/15771
FullText URL Mem_Sch_Eng_OU_18_1_75.pdf
Author Ohzuku Tsutomu| Hirai Taketsugu|
Abstract A basic kinetic equation of potential-step chronoamperometric current-time curve controlled by the rates of diffusion and electron transfer for a simple one-electron charge transfer reaction was given and various features of current-time curves were deduced from a theoretical treatment. The current-time equations for reversible and irreversible electron transfer processes appear as special cases with limited conditions of the equation reported in the present paper. And a potential-step chronoamperometric method to determine kinetic parameters from a current-time curve was proposed therefrom. The extension of a basic kinetic equation to more general multistep charge-transfer process was also considered.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1984-03-30
Volume volume18
Issue issue1
Start Page 75
End Page 89
ISSN 0475-0071
language English
File Version publisher
NAID 120002307131
JaLCDOI 10.18926/15770
FullText URL Mem_Sch_Eng_OU_15_2_29.pdf
Author Ohta, Mutsuo| Kanadani, Teruto| Sakakibara, Akira| Yamada, Masuo|
Abstract Measurements of electrical resistivity and intensity of small-angle X-ray scattering and transmission electron microscopy were made on Al-Zn alloys of several compositions. G.P. zones are formed by the nucleation-and-growth mechanism above the spinodal temperature. The nucleus has a critical size for growth. This size becomes larger when aged at higher temperatures. The sizes of the G.P. zones formed by this mechanism distribute broadly, but those formed by the spinodal decomposition do closely. The spinodal temperatures estimated for Al-10.0, 12.5, 15.0, and 20.0wt % Zn alloys are ~95, ~110, ~130, and ~180℃, respectively. The critical temperatures below which G.P. zones are observed in these alloys are ~115, ~135, ~160, and ~210℃, respectively.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1981-03-30
Volume volume15
Issue issue2
Start Page 29
End Page 53
ISSN 0475-0071
language English
File Version publisher
NAID 120002307895
JaLCDOI 10.18926/15769
FullText URL Mem_Sch_Eng_OU_15_2_21.pdf
Author Akagi Fumio| Osaki Hirokazu| Kikuchi Susumu|
Abstract An assembly line with no paralleling of work elements and work stations is called a serial line. The cycle time of the serial line must be at least equal to the maximum work element time. To lower the cycle time beyond the limit and increase the production rate, one may permit the paralleling of work elements or work stations. So in this paper we propose the parallel assignment method for achieving a higher production rate. In this method, work elements are assigned to work stations under the multiple upper time limits which are the products of the various numbers of workers and the limiting cycle time. Further we develop the computer program of the proposed method and provide an illustrative problem and computational results.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1981-03-30
Volume volume15
Issue issue2
Start Page 21
End Page 28
ISSN 0475-0071
language English
File Version publisher
NAID 120002307495
JaLCDOI 10.18926/15768
FullText URL Mem_Sch_Eng_OU_18_1_57.pdf
Author Ohzuku Tsutomu| Sawai Keijiro| Hirai Taketsugu|
Abstract Basic kinetic equations of chronopotentiometric potential-time curves, in which the equations for reversible, quasi-reversible and irreversible electron transfer process appeared in special cases, were given and a chronopotentiometric method for determining kinetic parameters was proposed therefrom. The method was demonstrated for Fe(3+)/Fe(2+) redox reaction in acidic aqueous media. The limitations of the method and the double-layer charging effects on the potential-time curve were discussed. The extension of the method to more general electrode processes was also considered.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1984-03-30
Volume volume18
Issue issue1
Start Page 57
End Page 73
ISSN 0475-0071
language English
File Version publisher
NAID 120002307985
JaLCDOI 10.18926/15767
FullText URL Mem_Sch_Eng_OU_18_1_43.pdf
Author Ohzuku Tsutomu| Hirai Taketsugu|
Abstract An equation on the current-polarization voltage characteristics of single charge transfer redox reaction on a rotating disk electrode (RDE) was given and a curvefitting method to determine kinetic parameters from an observed polarization curve was proposed therefrom. The method was demonstrated for Fe(2+)/Fe(3+)redox reaction in acidic aqueous electrolyte on Pt-RDE and the limitation of the method was discussed. The extension of the method to multistep charge transfer reaction was also considered.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1984-03-30
Volume volume18
Issue issue1
Start Page 43
End Page 56
ISSN 0475-0071
language English
File Version publisher
NAID 120002307914
JaLCDOI 10.18926/15766
FullText URL Mem_Sch_Eng_OU_15_2_1.pdf
Author Nakanishi Sen-ichiro| Ishida Hideaki| Himei Toyoji|
Abstract The systematic analytical method is reqUired for the ac phase control circuit by means of an inverse parallel thyristor pair which has a series and parallel L-C resonant load, because the phase control action causes abnormal and interesting phenomena, such as an extreme increase of voltage and current, an unique increase and decrease of contained higher harmonics, and a wide variation of power factor, etc. In this paper, the program for the analysis of the thyristor phase control circuit with a series and parallel connected load of series R-L-C circuit units, is been developed. By means of the program, the transient and steady state characteristics of the circuit can be calculated and then comparative study of various versions of circuits can be carried out systematically. The usefulness of the program is demonstrated by some numerical calculated examples.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1981-03-30
Volume volume15
Issue issue2
Start Page 1
End Page 19
ISSN 0475-0071
language English
File Version publisher
NAID 120002307503
JaLCDOI 10.18926/15765
FullText URL Mem_Sch_Eng_OU_15_1_111.pdf
Author Korenaga Takashi| Ikatsu Hisayoshi| Moriwake Tosio| Takahashi Teruo|
Abstract On the flow injection analysis (FIA) of chemical oxygen demand (COD), silver salt was added as an oxidation catalyst for COD substances and a masking agent for halide to improve operating conditions of the FIA apparatus. Both of a proper concentration of potassium permanganate solution and 6.0 % sulfuric acid solution containing 0.1 % silver nitrate are individually pumped up with respective flow rates of 0.51 ml min(-l) and merged into a carrier stream. A 20 μ1 of sample solution is injected into the flow of sulfuric acid solution at just before the merging place. The sample mixed with the carrier solutions in a reaction manifol(polytetrafluoroethylene tubing: 0.5 mm i.d. x 30 m), is passed through a thermostated bath at 100 °c and led to a flow cell for the absorbance measurements at 525 nm. The absorbances are continuously recorded with time. The peaks in the recordings showed good reproducibility and the calibration obtained at a linear concentration range of 0 - 170 mg 1(-1) COD with glucose as standard. The detection limit and precision confirmed with this method were 5 mg 1(-1) and 0.8 %, respectively. Chloride ion up to 200 mg 1(-1) did not interfere without elimination of a silver chloride precipitate. By the present FIA method, several industrial waste water samples were analyzed at a sampling rate of about 40 samples per hour, and their apparent COD values were compared with those found by the manual JIS method. Both of the methods gave the similar results within an error range from -35 to +5 %.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1980-11-29
Volume volume15
Issue issue1
Start Page 111
End Page 121
ISSN 0475-0071
language English
File Version publisher
NAID 120002307490
JaLCDOI 10.18926/15764
FullText URL Mem_Sch_Eng_OU_18_1_33.pdf
Author Osaki Hirokazu| Miyake Hirofumi| Kikuchi Susumu| Ogata Masana|
Abstract In this paper, we mentioned the apparatus developed to measure CFFs at the various point of the retina. Eleven CFFs measured at the central retina of both eyes (used usually} simultaneously, at the central retina of each eye separately, and at four points of the peripheral retina of each eye were analyzed together and referred to as the multi-point critical flicker fusion frequency (MCFF) . MCFF can be used to estimate the level of cortex activity, since the temporal and nasal parts of each eye are connected to different visual cortexes through the optic nerve. As the apparatus used to measure the MCFF was controlled by a micro-computer, the order of measurements and the calculation were done automatically.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1984-03-30
Volume volume18
Issue issue1
Start Page 33
End Page 42
ISSN 0475-0071
language English
File Version publisher
NAID 120002307595
JaLCDOI 10.18926/15763
FullText URL Mem_Sch_Eng_OU_15_1_101.pdf
Author Taniguchi Takeo| Numata Katsu|
Abstract In this paper the fill-in minimization problem which arises at the application of the sparse matrix method for a large sparse set of linear equations is discussed from the graph-theoretic viewpoint and also through the numerical experiments. Therefore, this investigation consists of two parts, and in the former part the author shows, at first, that the elimination process of a sparse matrix is equivalently replaced to the vertex eliminations for a graph obtained from the matrix, and by use of some concepts in the theory of graph he proves that the vertex elimination process for the minimum fill-in is equivalent to the vertex eliminations for vertices in each subgraph which is obtained by the appropriate dissection of whole graph, and that there are only two types of vertex eliminations through the process. This results in the proposal of a new model of the vertex elimination process. The latter part of this investigation is used for the verification of the results from the theoretic investigation. Through the numerical experiments he concludes that the new model of the vertex elimination process is valid, at least, for a graph like a regular finite element mesh. Furthermore, he shows that this model coincides with Nested Dissection Method which can give the minimum value of fill-in, at present.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1980-11-29
Volume volume15
Issue issue1
Start Page 101
End Page 110
ISSN 0475-0071
language English
File Version publisher
NAID 120002307966
JaLCDOI 10.18926/15762
FullText URL Mem_Sch_Eng_OU_18_1_1.pdf
Author Nakata Takayoshi| Takahashi Norio|
Abstract The quantitative analysis of localized flux distributions in transformer cores has become easy through the progress of numerical field calculations. In this paper, the effects of core constructions, joint configurations, magnetizing characteristics of materials on the flux distributions are examined using newly developed techniques such as a gap element, an approximate method for solving three-dimensional magnetic fields, the time periodicity finite element method, an efficient technique for treating hysteresis characteristics and so on. A method for the optimum design of transformer cores is also discussed. Main results obtained can be summarized as follows: (a) The building factor of the core made of higely-oriented silicon steel is larger than that of the conventional core. (b) The iron losses at joints are much affected by overlap lengths, number of laminations per stagger layer and a small irregularity of the arrangement of sheets. (c) It is clarified that examinations of the optimum construction of core and the most desirable magnetic characteristics of core material are possible using the finite element method.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1984-03-30
Volume volume18
Issue issue1
Start Page 1
End Page 31
ISSN 0475-0071
language English
File Version publisher
NAID 120002307976
JaLCDOI 10.18926/15761
FullText URL Mem_Sch_Eng_OU_15_1_79.pdf
Author Morikawa, Yoshitaka| Hamada, Hiroshi|
Abstract Two variational formulations for electromagnetic field and charged-particle stream configurations, in which both field and particles are described by the field-like variables suited for the problems of electrodynamics, are presented. One of them is directly obtained through slight modifications of Sturrock's original procedure but has a complicated form. The other is obtained through linearization of the preceding one and has a compact form. Both formulations lend themselves to straightforward derivation of the well-known energy-momentum tensor and/or its conservation law. Specifically the latter one is of academic interest because of its compact form. Moreover, as a proof of its practical usefulness the variational principle under the small-amplitude approximation is derived from it, which is known to provide a basis for the study of certain types of instability in plasmas. It is, however, hoped that it will find main applications in the electrodynamics problems concerned with large-amplitude behavior.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1980-11-29
Volume volume15
Issue issue1
Start Page 79
End Page 100
ISSN 0475-0071
language English
File Version publisher
NAID 120002307937
JaLCDOI 10.18926/15759
FullText URL Mem_Sch_Eng_OU_15_1_61.pdf
Author Furutani Yoichiro| Deutsch Claude| Gombert Marie M.| Oda Yoshinori|
Abstract Within the framework of the hydrodynamic guidingcenter approximation, we have investigated such quantum effects as the diffraction correction and the symmetry effect on the classical version of the particle diffusion coefficient D(1) across a dc magnetic field through the temperature-dependent pseudo-potentials. Analytic results are explicitly given with recourse to the order-of-magnitude estimate of a set of parameters pertaining to a laser-driven plasma.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1980-11-29
Volume volume15
Issue issue1
Start Page 61
End Page 78
ISSN 0475-0071
language English
File Version publisher
NAID 120002307432