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91.
Simulation of pyramid type three-roll bending process 总被引:2,自引:0,他引:2
A simulation of the deformation of a workpiece with a U-shaped cross section in a three-roll bending process is performed. Based on the properties of the workpiece, the distribution of curvature and bending moment are calculated in accordance with the displacement and the rotation of the rolls. The relationship between the position of the rolls and the final curvature of the workpiece is obtained. An experiment is performed and the accuracy of the simulation is confirmed. 相似文献
92.
Susumu Isaka Takeshi Yagisawa Tadashi Tokumasu Toshio Kase Shin-Ichi Menju 《Electrical Engineering in Japan》1996,116(6):72-82
In a three-phase, three-leg core of a core-type power transformer, the yokes are magnetically connected to all three phases so as to ease the flow of the magnetic flux (generally by means of lap joints of yokes and legs), and at the same time to smooth the magnetic flux between phase legs through yokes. It has generally been assumed that a split core with full separation at the center of the leg including yokes is unsuitable for use in power transformers owing to core losses, local heating, and noise resulting from the imbalance and distortion of magnetic flux, even though it can be used in distribution transformers with wound cores. But since the split core has many advantages from the manufacturing viewpoint, the magnetic characteristics of small core models were studied in detail. Studies with a full-scale 1500/3 MVA model transformer core indicate that the degradation of magnetic characteristics compares favorably with conventional cores. 相似文献
93.
Takashi Shinmoto Chiaki Kimura Ken Yamamoto Susumu Umeda 《Electrical Engineering in Japan》1996,116(5):75-84
The method for measuring insulation resistance by superimposing the dc voltage has potential for detecting the deterioration of cable insulations. The deterioration of cable insulations can be detected by measuring current which flows through a grounded shielding wire. However, the earth current also flows from the cable sheath into the grounding wire as noise. Thus, to assess the deterioration properly, it is necessary to separate the earth current from the total current. On the other hand, to improve detection sensitivity, it is desirable to superimpose the highest possible dc voltage. In this case, provision must be made so that there are no adverse effects on the GPT. The authors, placing special emphasis on the method of measuring high insulation resistance by configuring the bridge, have conducted an investigation on how to detect the insulation deterioration with high accuracy and sensitivity without impairing the functions of the GPT. The following issues were investigated and the results are reported in this paper: (1) It is possible to measure insulation resistance as high as 100,000 MΩ by superimposing 50-V dc through the GPT after cancelling the earth-current and by configuring a bridge for determining insulation resistance from voltage ratio. (2) Even if 50-V dc is superimposed through the GPT, it is possible to prevent the magnetic saturation of GPT if the current injected by such superimposition is limited (i.e., below max. 5 mA). (3) In lieu of a variable resistor, a variable dc voltage supply is employed in the bridge. The variable dc voltage supply requires no mechanically driven part, thus making it possible to realize a fully automatic monitoring system. 相似文献
94.
95.
Koichi Hatada Tatsuki Kitayama Shigeru Danjo Yutaka Tsubokura Heimei Yuki Kazuyuki Moriwaki Hiroaki Aritome Susumu Namba 《Polymer Bulletin》1983,10(1-2):45-50
Summary Polymer of α-substituted benzyl methacrylate was found to be used as a new type of positive electron-beam resist, which forms
methacrylic acid units in the polymer chain on the exposure to electron-beam and can be developed using alkaline solution
as a developer. The sensitivity was dependent on the bulkiness of the ester group and the number of ?-hydrogen atoms in the
ester group. The sensitivity and γ-value of atactic poly(α, α-dimethylbenzyl methacrylate) were improved by a factor of more
than three over poly (methyl methacrylate). 相似文献
96.
Ichinose Susumu Matsuki Makoto Higuchi Kazuhito 《Industry Applications, IEEE Transactions on》1985,(1):47-52
A new solid-state scanning ink jet recording technique, called slit jet recording, is proposed. This technique uses a recording head with one slitlike ink-issuing opening having a number of recording electrodes arrayed along a horizontal scanning direction. The ink is emitted from the ink-issuing opening due to the electrical potential difference between a driven recording electrode and a counterelectrode located behind the recording paper. The ink strikes the paper and forms a recording dot. Many recording electrodes can be driven simultaneously by video signals which enhance the total copy recording speed over that for conventional techniques using a single nozzle. The head of this ink jet recording apparatus is remarkably simple in construction and can be fabricated without difficulty. Improvements in reliability and maintainability can also be expected, as the simple structure of the ink-issuing opening reduces clogging and facilitates easy cleaning as compared with other equipment having a large number of nozzles. The recording principle and characteristics and ink-issuing characteristics are described, and the results of a trial recording are presented. The results show that an ISO A4 size (210 mm x 297 mm) full-color copy can be recorded in about 30 s at an 8-dot/ mm rate. 相似文献
97.
98.
99.
The colour stability of shisonin, a red pigment isolated from the leaves of a perilla (Perilla ocimoidesL. var. crispaBenth),was studied in model systems. At pH less than 6, the absorbance of shisonin in solution decreases with increase in pH. The degradation of shisonin in buffers at both pH 3 and 4 followed first-order reaction kinetics. Fructose, sucrose, metal cations Cu++ and Fe+++, hydrogen peroxide, oxygen and daylight affected the degradation rate of shisonin, while glucose, lactose, glycine and leucine had essentially no effect on the degradation rate. 相似文献
100.
Yamada Jun-Ichi Machida Susumu Mukai Takaaki Kano Hiroyuki Sugiyama Koichi 《Electronics letters》1979,15(19):596-597
Modulation experimenting on a buried-stripe (b.s.) InGaAsP laser emitting at 1.3 ?m was carried out up to 2 Gbit/s. The b.s. laser is free from relaxation oscillation, which degrades modulated optical pube waveforms, especially at high data rates. The repeater gain of 1.6 Gbit/s transmission systems is improved by 9 dB compared with previously reported experiments. Modulation characteristics up to 2 Gbit/s are reported. 相似文献