JaLCDOI 10.18926/15675
FullText URL Mem_Sch_Eng_OU_4_65.pdf
Author Himei Toyoji| Fujitsuka Takeshi| Inoue Jyunichi|
Abstract As one of the wide application of thyristor circuits, the inverter has a promising future and has been investigated vigorously. On the speed control of a squirrel cage induction motor by using a variable frequency thyristor inverter, although few papers have been presented, there seems to be many problems to be solved imminently. In this paper, the stability of performance of a thyristor inverter on this theme has been confirmed and some particular points with relation to practical use also have been discussed.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1969-09-01
Volume volume4
Issue issue1
Start Page 65
End Page 73
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307309
JaLCDOI 10.18926/15673
FullText URL Mem_Sch_Eng_OU_4_57.pdf
Author Takahashi Teruo| Kitamura Yoshiro|
Abstract Although the stability of Newtonian liquid jet has been investigated experimentally and theoretically, many problems has remained unsolved. Especially, the stability of liquid jets in immiscible liquid systems has been little studied. Furthermore, one has to point out that the stability of jets may be influenced by the turbulence in the nozzle and the velocity profile. This work presents the experimental result about the effect of the nozzle length on the breakup length of liquid jets in the air and in the immiscible liquid, as the beginning of a systematic investigation of the influence by these factors on the breakup of jet. The dependence of the initial amplitude of surface disturbances on the nozzle geometry is presented for evaluating the effect of the nozzle length on the breakup length of laminar liquid jet in the air and in the immiscible liquid.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1969-09-01
Volume volume4
Issue issue1
Start Page 57
End Page 64
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307482
JaLCDOI 10.18926/15672
FullText URL Mem_Sch_Eng_OU_4_51.pdf
Author Takahashi Teruo| Akagi Yasuharu|
Abstract In this report, the average holding time of gas in foaming layer and the number of transfer units based on gas-phase of the Rotational-current tray were considered experimentally. The average holding time was determined by water-air system. On the other hand, the number of transfer units was determined by water-ammonia-air system that gas-phase resistance controlled. The average holding time increases with gas and liquid velocities, and does not change with the tray dimensions clearly. From the experimental results of the number of transfer units, it was found that the tray can be operated at high efficiency up to larger gas and liquid flow rates than that of sieve trays.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1969-09-01
Volume volume4
Issue issue1
Start Page 51
End Page 56
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307449
JaLCDOI 10.18926/15635
FullText URL Mem_Sch_Eng_OU_4_35.pdf
Author Kaneda Yasuhiro| Osaki Hirokazu| Kikuchi Susumu|
Abstract 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.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1969-09-01
Volume volume4
Issue issue1
Start Page 35
End Page 38
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002308023
JaLCDOI 10.18926/15633
FullText URL Mem_Sch_Eng_OU_4_31.pdf
Author Osaki Hirokazu| Kikuchi Susumu|
Abstract 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.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1969-09-01
Volume volume4
Issue issue1
Start Page 31
End Page 34
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307392
JaLCDOI 10.18926/15631
FullText URL Mem_Sch_Eng_OU_4_19.pdf
Author Mizumoto Hisao|
Abstract 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.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1969-09-01
Volume volume4
Issue issue1
Start Page 19
End Page 30
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307219
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 英語
File Version publisher
NAID 120002307654
JaLCDOI 10.18926/15628
FullText URL Mem_Sch_Eng_OU_4_9.pdf
Author Hirose Koji| Oka Takuma|
Abstract 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.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1969-09-01
Volume volume4
Issue issue1
Start Page 9
End Page 12
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307589
JaLCDOI 10.18926/15627
FullText URL Mem_Sch_Eng_OU_4_1.pdf
Author Honda Kazuo| Konaga Tetsuro|
Abstract 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.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1969-09-01
Volume volume4
Issue issue1
Start Page 1
End Page 8
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307720