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JaLCDOI 10.18926/15644 Osaki Hirokazu| Kikuchi Susumu| 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. Memoirs of the School of Engineering, Okayama University 1972-07-10 volume7 issue1 1 9 0475-0071 英語 publisher
JaLCDOI 10.18926/15643 Nakata Takayoshi| Ishihara Yoshiyuki| In this paper, we report the procedure to analyse magnetic circuits and give the linear solutions on magnetic characteristics of the three-phase core-type transformer which is composed of the complicated magnetic paths. First, we explain the construction of cores investigated and normalize the sizes of a core. To analyse these magnetic circuits, we introduced the electrical eqcuivalent circuits and obtained the general fundamental equations for each core. Then, we drew the linear-numerical solutions using an electronic computer, and cleared the relationships between the sizes of a core and the amplitudes and phase angles of fluxes in magnetic paths. Related with the above facts, we investigate the influence of these sizes on the core loss using cores of various quality. Memoirs of the School of Engineering, Okayama University 1971-09-01 volume6 issue1 67 82 0475-0071 英語 publisher
JaLCDOI 10.18926/15642 Fujitsuka Takesi| Himei Toyoji| Wakabayashi Jiro| In this paper, the parallel inverter circuit with the load consisted of resistive load and constant reactive load in parallel, is analyzed taking into acourlt the d-c source reactance. The circuit has a good voltage regulation for the variation of resistive load current, except the vicinity of no load. The design method in using the results of analysis is also discussed. Memoirs of the School of Engineering, Okayama University 1971-09-01 volume6 issue1 61 65 0475-0071 英語 publisher
JaLCDOI 10.18926/15641 Monobe Kazuo| Murakami Yushi| Yokoyama Fumiyoshi| Crystalline adducts of urea with n-alkanes (C(8)~C(20)) and n-l-alkanols (C(12)~C(18)) were prepared. From thermal analysis and X-ray diffraction study on the adducts, we found that the composition of adducts and the heat of decomposition can be obtained easily from the thermogram of adducts. Memoirs of the School of Engineering, Okayama University 1971-09-01 volume6 issue1 57 60 0475-0071 英語 publisher
JaLCDOI 10.18926/15640 Yamashita Yuhiko| Monobe Kazuo| Lamellar crystals of amylose V complexes with the 6(1), 7(1) and 8(1) helical configurations can be prepared from aqueous solutions of amylose by using various complexing agents. It is noted that the crystal shape can be explained by the symmetry of the unit cell in the basal plane and the chain packing in the unit cell is cOncerned with the symmetry of helical chains. The existence of 6(1), 7(1) and 8(1) heliccs which occurs stepwisc with the number of glucopyranose an intger is discussed. Memoirs of the School of Engineering, Okayama University 1971-09-01 volume6 issue1 53 56 0475-0071 英語 publisher
JaLCDOI 10.18926/15639 Takahashi Katsuaki| Goto Yasumasa| The glass forming limit by substitution of CdS for CdO in a CdO-B(2)0(3) glass was determined by chemical analysis. When x CdS-(60-x)CdO-40B(2)0(3) nominal mixtures in weight ratio were heated at 1100°C in flowing nitrogen gas for 1/2 hour, about 40~50% of mixed CdS and 10-15% of the mixed CdS were evaporated. The limit of nominal composition for glass forming was 10CdS-50CdO-40B(2)0(3) and the corresponding virtual composition after the above heat treatment was found to be 4.9CdS-46.4CdO-48.7B(2)O(3). Further addition of CdS made the melt devitrefied with CdS precipitation. D.C. conductivity measurements revealed that the current density was not linear with respect to the applied voltage, but the resistivity ranged around 10(12)Ω･cm for 4.1CdS-48.8CdO-47.1B(2)O(3) (virtual composition) glass and around 10(11.5)Ω·cm for 4.9CdS-46.4CdO-48.7B(2)O(3) glass. These sulphur containing glasses did not show photoconduction, although CdS-precipitated materials showed slight photoconductivity when disposed in ultra violet radiation. Apparent dielectric constant and tan 8 were also measured as a function of frequency, revealing a moderate dispersion in the CdS-precipitated glasses. Memoirs of the School of Engineering, Okayama University 1971-09-01 volume6 issue1 47 52 0475-0071 英語 publisher
JaLCDOI 10.18926/15636 Ohta Mutsuo| Hashimoto Fumio| Maeda Hironobu| Fiber textures of drawn wires of Al-Zn alloys containing precipitates were studied mainly by X-ray methods. In supersaturated solid solution the wire texture was a double fiber texture with [100]and [111]. It was considered that a phase precipitates were rotated with matrix, while they were deformed. And then the matrix containing stable precipitates (Zn) had [100] and [111] textures. The intense spots, corresponding to [111] fiber texture of matrix, in the Debye rings of (002)p and (101)p planes of precipitates were clearly observed. But, on the other hand, spots, corresponding to [100] fiber texture of matrix, shown the prefered orientation of precipitates in (002)p Debye ring were very weak and brodening. Memoirs of the School of Engineering, Okayama University 1971-09-01 volume6 issue1 27 31 0475-0071 英語 publisher
JaLCDOI 10.18926/15635 Kaneda Yasuhiro| Osaki Hirokazu| Kikuchi Susumu| Insuring fast and precise human operation is one of the engineering requirements in the developing civilization. Some man-machine system, when any operator is exposed himself to some kind of vibration, he may not perform his operation in good conditions. Then one of the interferring factors, there is a fatigue caused by vibration. In this study, subjects sit on the chair which was set on the vibration table, and were shaken vertically for some given times, then were measured whether the fatigue occured or not by flicker friction tester. Flicker patterns were analyzed according to each vibration-condition, then the authors knew that the fatigue was occured by vibration. Memoirs of the School of Engineering, Okayama University 1969-09-01 volume4 issue1 35 38 0475-0071 英語 publisher
JaLCDOI 10.18926/15634 Wada Tsutomu| Shimizu Akira| In this report, the effects of splitter position on the attached jet were experimentally investigated for the purpose of discussing the applicability of a usual mathematical model without splitter. As results, the followings were confirmed, (l) For the splitter distance shorter than the critical distance, the pressure in the bubble lowers and the jet radius of curvature shortens. (2) At the ratio L(s)/D=4~5, the switching control flow rate becomes maximum. And bordering this value, the effects of splitter position on the switching are quite conversely. For the splitter distance longer than the above value, the switching control flow rate decreases, as increasing the distance. (3) For the splitter distance of 1.5~2 times critical distance, the switching is almost never affected by the splitter. Memoirs of the School of Engineering, Okayama University 1971-09-01 volume6 issue1 21 25 0475-0071 英語 publisher
JaLCDOI 10.18926/15633 Osaki Hirokazu| Kikuchi Susumu| The appropriate disposition of the worker improves the ability of the worker and the efficiency of the labor and further decreases the rate of inferior goods and the rate of accidents. In previous paper, the variation of the flicker value, the trend of the miss frequency and the relation between them under the condition which has one surveillance point and one back-ground condition are analyzed. In this paper, the surveillance point is increased to two points and the back ground condition also two in order to examine which condition influences strongly to the flicker value in the working time. It was found that the variation of the flicker value is strongly connected with the qualification, the number of the surveillance and its miss-frequency. Memoirs of the School of Engineering, Okayama University 1969-09-01 volume4 issue1 31 34 0475-0071 英語 publisher
JaLCDOI 10.18926/15632 Osaki Hirokazu| Kikuchi Susumu| The equipment measuring the critical flicker fusion frequency (CFF) is made in order to measure many subjects' CFF at the same time. This equipment is defined the multi-flicker. The equipment measuring CFF, used until now is defined the mono-flicker. It is analysed what factors influence CFF strongly. Then it is made clear that CFF value measured by the multi-f1icker can be used to show the brain weariness as well as that of the mono-flicker, and the vigual angle and the intensity of illumination in the room influence CFF value strongly. Memoirs of the School of Engineering, Okayama University 1971-09-01 volume6 issue1 13 19 0475-0071 英語 publisher
JaLCDOI 10.18926/15631 Mizumoto Hisao| In paper 7) we concerned ourselves with the conformal mapping onto circular-radial slit covering surfaces over the whole plane and its extremal property. In the present paper we shall concern ourselves with the conformal mapping onto circular-radial slit covering surfaces of annular and circular types and their extremal properties (Theorems 1.1 and 2.1). Especially the extremal property with respect to the radial slits is new. The results are stated only for the case of the planar domain of finite connectivity. The method suggests the possibility of an extension to the case of a domain of infinite connectivity or an open Riemann surface of finite genus. We shall concern ourselves with this problem in the subsequent paper. Memoirs of the School of Engineering, Okayama University 1969-09-01 volume4 issue1 19 30 0475-0071 英語 publisher
JaLCDOI 10.18926/15630 Hirose Koji| Oka Takuma| A series of turbulent pipe flow experiments with dilute aqueous C.M.C. solutions are described. The purpose of these experiments are to compare the anomalous viscous drag results from these experiments with the results using water (Newtonian viscous fluid). The additive concentrations of the present experiments are from 0.01% to 0.5% by weight of C.M.C., giving power-law indexes 1 to 0.75, respectively. All of the concentrations are found to give a reduction in turbulent friction factor, compared with Newtonian at the same Reynolds number. A maximum friction factor reduction of 64 % is obtained at a Reynolds number 2x10(3) for solutions having polymer concentration of 0.3% by weight. Memoirs of the School of Engineering, Okayama University 1971-09-01 volume6 issue1 7 12 0475-0071 英語 publisher
JaLCDOI 10.18926/15629 Hirose Koji| Asano Yoshihiro| 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. Memoirs of the School of Engineering, Okayama University 1969-09-01 volume4 issue1 13 17 0475-0071 英語 publisher
JaLCDOI 10.18926/15628 Hirose Koji| Oka Takuma| In this study, the friction factors of unsteady pipe flows have been experimentally investigated. The normal temperature water was used as working fluid and pulsating flow superposed on the steady turblent flow, having the variation of velocity approximately represented by sine curve, was used. In the result, the time mean friction factors of the unsteady flow agree with that of steady flow, and the momentary friction factors in the accelerating state are smaller and in the decelerating state larger than that in steady flow for each Reynolds numbers. Memoirs of the School of Engineering, Okayama University 1969-09-01 volume4 issue1 9 12 0475-0071 英語 publisher
JaLCDOI 10.18926/15627 Honda Kazuo| Konaga Tetsuro| In the present paper, to provide information on the stress measurement in coarse grained materials by X-ray micro-beam diffraction technique using a crystal oscillation method, the authors first examined experimentaly and theoretically the relation between the sizes of X-ray beam and crystal to obtain the particular diffraction ring in the case of use of crystal oscillation method. The specimen attachment of X-ray camera used in this experiment can be oscillated automatically around a horizontal and vertical axes with high accuracy centering around an illuminated position on the specimen surface. Accordingly it is possible to increase the number of the diffraction spots without changing the area and position of the specimen illuminated. Experiments were carried out for three kinds of annealed low careon steel with grain sizes of about 15, 30 and 50μ in diameter, and with X-ray beam collimated by pinhole slits of 0.12, 0.30 and 1.00 mm in diameter, using CrKα characteristic X-rays. On the other hand, a theoretical analysis was carried out according to the X-ray diffraction theory which have been proposed by P. B. Hirsch et al. As the conclusion, it is found that the crystal oscillation method is extremely useful for X-ray stress measurement of coarse grained materials. Moreover, the conditions of the crystal oscillating operation were clarified theoretically for any pair of the sizes of X-ray beam and crystal. Memoirs of the School of Engineering, Okayama University 1969-09-01 volume4 issue1 1 8 0475-0071 英語 publisher
JaLCDOI 10.18926/15626 Honda Kazuo| Konaga Tetsuro| It is very important to clarify the question whether fatigue crack propagation will be affected by mechanical propaties or other propaties of materials. In the present paper the authors studied in relation of yield strength and stacking fault energy to rate of fatigue crack propagation. αbrass were chosen for the investigation because they provided sufficient range in both quantities of interest that either could be varied independently of the other. Fatigue tests were carried out under full bending moment of flat specimens with V-shape notch. Chosen stress levels were 0.6 σy and 0.8 σy in which σy is yield strength, rate of fatigue crack propagation was evaluated from the second stage of the curve of fatigue crack propagation. The dependence of the rate on stacking fault energy γ was found to be dl/ dN=G・γ(n). But dl/dN did not systematically to change in yield strength. Thus, γ is concluded to be the controlling variable. Memoirs of the School of Engineering, Okayama University 1971-09-01 volume6 issue1 1 6 0475-0071 英語 publisher
JaLCDOI 10.18926/15625 Monobe Kazuo| Yamashita Yuhiko| Fujiwara Yasuo| Fujiwara Yoshitaka| We tried to clarify the crystallization mechanism of long chain polymers in solution under shearing stress using polyethylene. From the bright and dark field electron microscope observations and the electron diffraction study, we demonstrated that the resulting fibrous crystals consist of the central threads with an extended chain character and the lamellae with a folded chain character nucleated on the threads. The measurements of thermal and mechanical properties gave the additional confirmation for this suggestion. From these results we discussed the crystallization mechanism on the fibrous crystals. Memoirs of the School of Engineering, Okayama University 1968-09-01 volume3 issue1 77 83 0475-0071 英語 publisher
JaLCDOI 10.18926/15624 Misaki Takayoshi| Okamoto Takuji| Kato Osamu| In the analog circuits for the systms governed by the dilfercntial equations with the coefficients which are a function of one or mOre of the dependent variables, the magnitudes of their circuit elements must be variable in accordance with the nature of the function. Such circuit elements can be realized by means of inserting or removing the additional elements with high speed switches in the analog circuits. Particularly, in the case of varying stepwise this method is effective. But as an analog circuit is regarded as a short-time or repetitive type analyzer, the above switches must be instantaneous operation. In this paper, first, it is made sure by the experiments that some of the transistor switches arc met this condition, and moreover arc very low closed resistance, very high open resistance and neglegible small voltage offsets. Next, the basic technique for the direct analog simulation usiug transistor switches is described about the simple example, i.e. the oscillatory system with varying cross-scctional surge tank. Finally, as its applications, the transient problems of these oscillatory systems arc solved by means of these analog circuits. Memoirs of the School of Engineering, Okayama University 1968-09-01 volume3 issue1 157 162 0475-0071 英語 publisher
JaLCDOI 10.18926/15623 Himei Toyoji| Inoue Jyunichi| Kondo Tadao| Nakanishi Senichiro| The waveform of the load current has been analyzed theoretically on the single-phase series R-C circuit controlled by the back to back SCR pair. And then, the fluctuation of the barmonics calculated by the use of the electronic digital computer, has been discussed as for the firing angles of SCRs and the phase angle of load. Memoirs of the School of Engineering, Okayama University 1968-09-01 volume3 issue1 151 155 0475-0071 英語 publisher