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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
JaLCDOI 10.18926/15756
FullText URL Mem_Sch_Eng_OU_15_1_47.pdf
Author Koga, Ryuji| Nagase, Satoru| Kosaka, Megumi| Sano, Hiroya|
Abstract Basic prohlems are discussed about a local, realtime and very sensitive air-pollution monitoring using a laser diode. The method employs the second derivative spectrometry replacing the incoherent light source and mechanical choppers in a traditional method with the laser diode and a newly developed electronic system. Etalon fringes at this system becomes the dominant noise source and its statistic and dynamical features are to be understood. Numerical examination was done for the optimal width of optical frequency modulation. A very fast measurement of weak absorption spectra became possible by the development of lock-in-amplifiers with finite integration time instead of a low-pass filter. Spectra of methane in 7.6 μm region and a time-dependent spectrum of the etaIon fringe are shown.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1980-11-29
Volume volume15
Issue issue1
Start Page 47
End Page 60
ISSN 0475-0071
language English
File Version publisher
NAID 120002307627
JaLCDOI 10.18926/15749
FullText URL Mem_Sch_Eng_OU_14_2_73.pdf
Author Kono Iichiro| Nishigaki Makoto|
Abstract This paper deals with the experimental study of hydraulic properties of unsaturated soil. In treating unsaturated zone, a great deal more data are required than are required for the saturated zone, but these properties of soils must be known to apply the finite element approach to actual groundwater flow problems. The purposes of this paper are to propose a rational basis of getting experimental relationships between prossure head() and hydraulic conductivity(K) and between pressure head() and volumetric moisture content(θ) with "the instantaneous profile method" in a laboratory. An apparatus was constructed and test procedures were developed to measure pressure head and volumetric moisture content by using pressure transducers and low-energy gamma ray attenuation. The technique of a low-energy gamma radiation apparatus does provide a means for accurate measurement of water content without disturbing the system into which water is moving. Furthermore rapid measurement of water content becomes possible at any position in a soil so that water content changes with time may easily be followed. The tensiometer~transducer system provides a most valuable means of measuring pressure head with rapid response and with provision of a complete record of the pressure head changes with time.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1980-03-01
Volume volume14
Issue issue2
Start Page 73
End Page 110
ISSN 0475-0071
language English
File Version publisher
NAID 120002307379
JaLCDOI 10.18926/15732
FullText URL Mem_Sch_Eng_OU_13_249.pdf
Author Yamamoto Kyoji|
Abstract The asymptotic theory of Rayleigh shear flow for large values of time is developed on the basis of the linearized Boltzmann-Krook equation. Asymptotic equations for mean velocity outside the Knudsen layer are obtained by employing the Hilbert expansion. Slip boundary conditions are derived from the analysis of the Knudsen layer adjacent to the wall. A solution of the asymptotic equation is obtained under the slip boundary condition and zero initial condition. Discussions are also made of the flow induced by a slowly oscillating flat plate.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1979-03-05
Volume volume13
Start Page 249
End Page 258
ISSN 0475-0071
language English
File Version publisher
NAID 120002307963
JaLCDOI 10.18926/15728
FullText URL Mem_Sch_Eng_OU_13_225.pdf
Author Kaneda Masahiro| Shinji Hiroshi| Aoyama Mikio|
Abstract This paper deals with the adaptive observer which estimates the states and parameters of unknown system. It is shown that the adaptive observer problem is reduced to the identification of the transformation matrix for an arbitrary designable observer. Moreover, the adaptive process of the unknown parameters is reduced to the linear optimal regulator problem. As the result, a new method is presented to obtain an appropriate adaptive process with good insight. And, in this identification, a linear filter is found to be also useful against noises in input-output data. To achieve high accuracy, a particular nonlinear filtering can improve SN ratio only in the direction of the unknown vector. Even if SN ratio of input-output data has zero dB, sufficient accuracy can be accomplished within suitable correction time. This design algorithm seems to be rather straightforward and practical. Since input sequence is required to be only sufficiently general, the method is applicable to on-line identification also.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1979-03-05
Volume volume13
Start Page 225
End Page 238
ISSN 0475-0071
language English
File Version publisher
NAID 120002307984
JaLCDOI 10.18926/15725
FullText URL Mem_Sch_Eng_OU_12_59.pdf
Author Ohta, Mutsuo| Kanadani, Teruto| Sakakibara, Akira|
Abstract Several Al-Zn alloys containing 0.041-4.4 at % Zn were studied by means of measurements of electrical resistivity. The results obtained are as follows : (1) The electrical resistivity increases when the specimen is annealed at temperatures higher than the solvus temperature of the G.P. zones. The increase of the resistivity is due to the formation of fluctuation. (2) The electrical resistivity of the specimen containing fluctuation is dependent upon annealing temperature only and independent of quenching temperature. (3) The fluctuation is formed in very dilute alloys as 0.041 at % Zn at temperatures higher than the solvus temperature of the G.P. zones. (4) The formation energy of vacancy and the migration energy of the Zn atom in the alloys determined by the formation process of fluctuation are in good agreement with those by the formation process of G.P. zones. (5) In spite of the result (4), it seems that the fluctuation is not the same as the small G.P. zones which are observed in the early stage of aging.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1978-02-25
Volume volume12
Start Page 59
End Page 75
ISSN 0475-0071
language English
File Version publisher
NAID 120002307636
JaLCDOI 10.18926/15723
FullText URL Mem_Sch_Eng_OU_13_195.pdf
Author Sano, Hiroya| Koga, Ryuji| Tanada Yoshihiro| Kosaka, Megumi|
Abstract The maximally attainable accuracy of an airpollution monitoring system is investigated. The system is composed of a tunable pulsed dye laser as the light source, photodiodes as the opto-electric converter and a low noise electronic signal processor specifically designed by the authors. The extreme value of the accuracy is given in terms of the standard deviation of the attenuation. The value is 3.4×10(-4)[Nep√(pulse number)] for an averaged value for multiple laser shots. Also the wavelength reproduceability of a dye laser was examined, which resulted in that a computer should take a part in the wavelength control in order that this method should be feasible.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1979-03-05
Volume volume13
Start Page 195
End Page 207
ISSN 0475-0071
language English
File Version publisher
NAID 120002307857
JaLCDOI 10.18926/15715
FullText URL Mem_Sch_Eng_OU_13_133.pdf
Author Ohta, Mutsuo| Kanadani, Teruto| Yamada, Masuo| Sakakibara, Akira|
Abstract Aging and reversion in dilute Al-Ag alloys are studied by means of the measurements of electrical resistivity. Results obtained are as follows: 1) Increase in the as-quenched resistivity is found for a low quenching temperature. This increase may be due to the fluctuation of solute concentration at the quenching temperature. 2) When the fluctuation exists in the alloy, the aging rate becomes slow and the maximum resistivity in the isothermal aging curve becomes small as the vacancyconcentration becomes low. The maximum resistivity becomes large again when the vacancy concentration becomes further lower, and finally the maximum does not appear. 3) These behaviors are explained in terms of the difference in the rate of growth of the G.P. zones in the regions of higher and lower solute concentration induced by the fluctuation and in terms of the change of this difference with vacancy concentration. 4) G.P. zones may be formed by the spinodal decomposition with indefinite surfaces at first, grown to larger ones with difinite surfaces and changed to ordered nzones in the alloy. 5) It is confirmed that G.P. zones are formed by the nucleation-and-growth mechanism also in Al-Ag alloys above the spinodal temperature.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1979-03-05
Volume volume13
Start Page 133
End Page 152
ISSN 0475-0071
language English
File Version publisher
NAID 120002307468
JaLCDOI 10.18926/15710
FullText URL Mem_Sch_Eng_OU_11_2_27.pdf
Author Nago Hiroshi|
Abstract In this paper the influence of a vertical lip upon the contraction coefficients of underflow gates is discussed. The coefficients of inclined gates with a vertical lip are investigated theoretically by using the method of conformal mapping. Solutions are obtained numerically for several values of the inclination of gate bottom. Theoretical solutions show that;as the length of a lip increases, the coefficient rapidly decreases from the value for the inclined gate, and when the length becomes of the order of a gate openning,it takes a value to be nearly equal to that for a vertical gate. These theoretical results are verified by experiments.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1977-01-25
Volume volume11
Issue issue2
Start Page 27
End Page 36
ISSN 0475-0071
language English
File Version publisher
NAID 120002307779
JaLCDOI 10.18926/15709
FullText URL Mem_Sch_Eng_OU_13_95.pdf
Author Ohta, Mutsuo| Kanadani, Teruto| Yamada, Masuo| Sakakibara, Akira|
Abstract Aging process in Al-Zn alloys was studied by the measurements of the electrical resistivity when the alloy was quenched from a high temperature, about 300℃ (the first quenching temperature), to an intermediate temperature, between 110℃ and 230℃ (the second quenching temperature), held at this temperature for a time, quenched again into iced water and aged at a low temperature. Variation of the holding time at the second quenching temperature brings about the variation of the isothermal aging curves. Maximum resistivity of the isothermal aging curve, p(max) , decreases at first, passes a minimum and then increases to reach a stationary value as the holding time at the intermediate temperature increases. It is pointed out that this phenomenon is mainly due to the fluctuation of solute concentration and the vacancy concentration decreasing at the intermediate temperature.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1979-03-05
Volume volume13
Start Page 95
End Page 117
ISSN 0475-0071
language English
File Version publisher
NAID 120002307526
JaLCDOI 10.18926/15696
FullText URL Mem_Sch_Eng_OU_13_1.pdf
Author Tanaka Yutaka|
Abstract In this paper, is proposed a calculating method for the simulation of oscillatory combustion state, and comparisons between estimation results and experimental ones are carried out. With respect to the effects of geometric dimensions of combustion system, and of fueland air-flow rate conditions on characteristics such as an amplitude of oscillation, its fluctuation, and a frequency, a theoretical analysis presents a correct estimation of the phenomena. By use of this analysis, it becomes possible exactly to estimate the changes which take place in the combustion system. On the basis of the quantitative feature of the theoretical results, the influences of the factors such as ignition lag, wall temperature ratio, and heat transmission on the combustion oscillation are studied.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1979-03-05
Volume volume13
Start Page 1
End Page 24
ISSN 0475-0071
language English
File Version publisher
NAID 120002307496
JaLCDOI 10.18926/15693
FullText URL Mem_Sch_Eng_OU_10_2_81.pdf
Author Sakakibara, Akira|
Abstract To acquire information on the interaction between oxygen molecules in solid phase, studies have been carried out on the magnetic properties of solid oxygen, oxygen-argon and oxygen-fluorine. Review of the studies on the interaction between oxygen molecules is cited. Magnetic susceptibility was measured by the Faraday method as a function of temperature from 12 K to the melting point of them. Pure oxygen both in α and β phase indicates paramagnetism corresponding to long-range antiferromagnetic order. Oxygen -argon mixtures of 92~66 mol% oxygen content indicate large susceptibility corresponding to δ phase, which can be interpreted in terms of the cluster of oxygen molecules in trimer. Small paramagnetism was found for the oxygenfluorine mixture even as dilute as 10 mol% oxygen content, which may be due to the strong antiferromagnetic interaction. This can be interpreted in terms of super-exchange interaction between oxygen molecules via fluorine molecule.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1976-01-27
Volume volume10
Issue issue2
Start Page 81
End Page 111
ISSN 0475-0071
language English
File Version publisher
NAID 120002307359
JaLCDOI 10.18926/15691
FullText URL Mem_Sch_Eng_OU_5_47.pdf
Author Takahashi Katsuaki| Miura Yoshinari|
Abstract Diffusion phenomena of silver ion in the molten sodium diborate of low silver ion content were investigated at the temperature range from 880℃ to 625℃ by means of chronopotentiometry. From the results, it was shown that the silver ion was reduced reversibly to metallic state at the silver electrode used and silver ion was transported only by diffusion in case that transition time in a potential-time relation was within several seconds. Diffusion coefficients measured at various temperatures satisfied Arrhenius equation. The activation energy of diffusion and diffusion coefficient were respectively 32Kcal/mol and 6.5×10(-7) cm(2)/sec at the liquidous temperature. By comparing these values with those obtained in some molten salts, the difference of structure between the molten glass and molten salts was discussed. Moreover, the consideration for the size of borate anion existing in the molten glass was also tried from the viewpoint of rate process and from Stokes-Einstein's equation.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1970-09-01
Volume volume5
Issue issue1
Start Page 47
End Page 53
ISSN 0475-0071
language English
File Version publisher
NAID 120002307810
JaLCDOI 10.18926/15681
FullText URL Mem_Sch_Eng_OU_10_2_1.pdf
Author Honda Kazuo| Hosokawa Norio| Sarai Takaaki|
Abstract The diffracted intensity of X-ray depends upon several physical and geometrical factors such as structure, multiplicity, absorption and Lorentzpolarization and measuring conditions such as time constant and scanning speed of detector on counter method[l]. For analyzing on the X-ray stress measurement, especially, profile shape of X-ray diffraction which is affected by geometrical factors such as absorption and Lorentz-polarization is very important. In order to eliminate these factors affecting the stress measured by using X-ray, the correcting factors were introduced and those theoretical values were calculated. After this theoretical calculation, it is found that as the half value breadth increases the difference between the stress measured by using X-ray and the corrected one becomes larger and larger under same measuring condition. When the ideal diffracted intensity of X-ray is assumed Cauchy distribution the measured stress depends upon measuring condition for same specimen, but it is independent of measuring condition in Gauss, distribution. Consequently, it is found that the stress measured by using X-ray must be corrected under each measuring condition and the method of correction is made clear and proved experimentally in this paper.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1976-01-27
Volume volume10
Issue issue2
Start Page 1
End Page 13
ISSN 0475-0071
language English
File Version publisher
NAID 120002307339
JaLCDOI 10.18926/15678
FullText URL Mem_Sch_Eng_OU_10_1_39.pdf
Author Ohta Mutsuo| Hamamoto Takao|
Abstract As to Al-Zn alloy, the difference between the formation of G.P.zones and that of clusters was investigated by measurements of electrical resistivity. The results obtained were summarised as follows: (1) G.P.zones formed during the quench and quenched-in vacancies increase greatly as-quenched resistivity P(o) as quenching temperature Tq is raised, and clusters increase slightly P(o) as Tq is lowered. (2) For one Tq and one Ta, the time required to reach P(e)' for Al-1.3at % Zn alloy is longer than that for Al-3.0at % Zn alloy. This is due to the difference of number of zinc atom in the clusters. (3) For one Ta and one concentration of zinc, the time required to reach p'(e) at Tq = 170℃ is longer than that at Tq = 300℃. This is due to the difference in concentration of quenchedin vacancies. As to Al-Cu alloy, the solvus temperature for G.P.zones was determined from the existence of P(m) in ageing curves by measurements of electrical resistivity. Consequently the solvus temperature is between 20℃ and 60℃.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1975-07-01
Volume volume10
Issue issue1
Start Page 39
End Page 47
ISSN 0475-0071
language English
File Version publisher
NAID 120002307266
JaLCDOI 10.18926/15663
FullText URL Mem_Sch_Eng_OU_9_1_11.pdf
Author Ohta Mutsuo| Nagai Makoto|
Abstract Metastable values of electrical resistivity, P(E)' obtained during isothermal ageing differs in each experimental run even when the conditions of quenching and ageing were carefully kept constant. This phenomenon is considered to result from the competitive growth of G.P.zones. The range of the values of P(E) under the same conditions of heat treatments were examined, and the results obtained are as follows: (1) Metastable values of resistivity, P(E), during ageing at 70℃ after quenching from 300℃ were in rather narrow range. On the other hand, the width of the range obtained during ageing at 50℃ was wide. (2) When the specimens were aged at first at 70℃ until the maximum values of resistivity, P(M), being reached and then aged at 50℃ for long time, the metastable values of resistivity, PE*, were obtained. And the width of discrepancy of values of P(E)* was nearly equal to that of P(E) which was obtained in the case of isothermal ageing at 70℃ after quenching from 300℃. (3) It may be concluded that the width of discrepancy of values of P(E)* becomes smaller since the width of discrepancy of the number of G.P.zones for all experiments which can grow through competitive growth is made small by 70℃ ageing than that immediately after quenching from 300℃.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1974-07-20
Volume volume9
Issue issue1
Start Page 11
End Page 21
ISSN 0475-0071
language English
File Version publisher
NAID 120002307817
JaLCDOI 10.18926/15648
FullText URL Mem_Sch_Eng_OU_7_1_31.pdf
Author Ishii Tadao|
Abstract A theory, based on Chambers' method to the classical Boltzmann equation, is developed for an acoustic amplification in both degenerate and nondegenerate piezoelectric semiconductors subjected to the Hall geometrically configured electric and magnetic fields. It is found that an amplification constant for qR>1 holds not only for a magnetic field ω(c)τ>1 but for ω(c)τ<1 under ql>1 while the amplification constant for qR<1 does for ql≦1 under ω(c)τ>1; q is the wave number vector of sound, R the cyclotron radius, ω(c) the cyclotron frequency, 1 the mean free path and τ the relaxation time. A generalized attenuation (amplification) constant is presented through an energy conservation law, being applicable to the sounds propagating at any angle with respect to the particle drift so the off-axis as well as on-axis amplifications are surely involved. An application of the present theory to n-InSb reveals a threshold dependence for the acoustic amplification, which is semi-quantitative agreement with the experimental result of Arizumi et al.. The amplification constant by that nondegenerate particles is found to be almost equal to that by the degenerate ones, provided that the former carrier density should be replaced by its three times as much.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1972-07-10
Volume volume7
Issue issue1
Start Page 31
End Page 42
ISSN 0475-0071
language English
File Version publisher
NAID 120002307574
JaLCDOI 10.18926/15644
FullText URL Mem_Sch_Eng_OU_7_1_1.pdf
Author Osaki Hirokazu| Kikuchi Susumu|
Abstract This paper deals with the empirical formula to explain the work amount curve of a worker during a work. The empirical formula yt = at(b) + c was used to explain this phenomenon until now. This formula has been used mainly to approximate to the monotonous trend of the work amount curve. But it was made clear that if the work amount curve showed the polynomial trend, it could not be done so. Then the authors attempt to establish the empirical formula yt = a/{exp(Σb(i)t(i))-l} + c, which was the general form of the logistic curve in order to explain not only the monotonous trend but also the polynomial trend of the work amount curve. And it was made clear from the results of the approximation that this formula was the one of the most usuful formula in order to explain the work amount curve.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1972-07-10
Volume volume7
Issue issue1
Start Page 1
End Page 9
ISSN 0475-0071
language English
File Version publisher
NAID 120002307630
JaLCDOI 10.18926/15629
FullText URL Mem_Sch_Eng_OU_4_13.pdf
Author Hirose Koji| Asano Yoshihiro|
Abstract In this study, friction coefficients for sectionally roughened square ducts were measured for transional and turbulent flow. The velocity fields in the cross section were mesured for turbulent flow, and the predicting equation in the previous report was corected.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1969-09-01
Volume volume4
Issue issue1
Start Page 13
End Page 17
ISSN 0475-0071
language English
File Version publisher
NAID 120002307654
JaLCDOI 10.18926/15617
FullText URL Mem_Sch_Eng_OU_3_119.pdf
Author Takeda Akira| Wada Satosi| Uno Takaaki| Masuike Taketosi| Torii Sigeru|
Abstract The preparation of the title compounds as a new type of stable S-ylides has been described. The reaction of 1-dimethylsulfuranylidene-1-phenylsulfonyl-2-propanone (IIb) with lithium aluminium hydride was found to result in the formation of trans-phenylpropenylsulfone (IV), phenylsulfonyl-2-propanone (Ib), and an unidentified paraffin as major products.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1968-09-01
Volume volume3
Issue issue1
Start Page 119
End Page 122
ISSN 0475-0071
language English
File Version publisher
NAID 120002307991