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101.
For lightweight and compact implementation of a generation set, many attempts have been made by some researchers to develop a brushless self-excited synchronous generator without an ac exciter. A previous paper proposed a novel self-excitation scheme by which the second-space harmonic component of armature mmf is used for exciting the rotor field system. In this excitation scheme the effect of the series excitation characteristic, as well as a self-excited and brushless implementation without an ac exciter is automatically obtained. However, in the case of system configuration of the generator already reported, voltage regulation in the inductive load condition was very large. To remove this problem, this paper presents a new system configuration of the generator with a self-regulating feature that can compensate voltage regulation automatically. The new generator consists of a stator installing two three-phase windings, externally connected to a load and a capacitor bank, respectively, and a rotor with field and harmonic windings. In this paper the system configuration and theoretical concepts of the presented generator are described and detailed experimental investigations with a laboratory machine are also shown. 相似文献
102.
Young-Geun Park Teruo Kanki Hea-Yeon Lee Hidekazu Tanaka Tomoji Kawai 《Solid-state electronics》2003,47(12):2221
We investigated a photoconductor(PC)/ferroelectric oxide(OF)/semiconductor oxide(SO) POS-FET structure photomemory consisting of organic photoconductor CuPc/inorganic ferroelectric PbZr0.2Ti0.8O3 heterojunction gate and a ferromagnetic oxide semiconductor La0.87Ba0.13MnO3 channel. Visible light information detected by photoconductor CuPc can be memorized in ferroelectric PbZr0.2Ti0.8O3, and non-volatile and non-destructive reading out process of light information memorized in this ferroelectric layer were achieved by reading out the resistance modulation of ferromagnetic semiconductor oxide La0.87Ba0.13MnO3 channel under the photoconductor/ferroelectric gate. 相似文献
103.
A 3 dB gain-reduction bandwidth up to 65 nm (1549-1614 nm) is achieved using a two-stage erbium-doped fibre amplifier, together with an intermediate equaliser and Raman amplification in the transmission fibre 相似文献
104.
The effects of the GABAergic pathway on the dynamic range of the light response of cone-driven horizontal cells (HCs) in the carp retina were investigated using conventional intracellular recordings and computer simulations. The amplitude of the HC responses to repetitive test flashes was altered by background illumination in control Ringer's solution, but was not changed following the application of picrotoxin or bicuculline, which suggests that GABAA receptors mediate the subsequent change in light response. This phenomenon was simulated by introducing the desensitization mechanism of the GABAA receptor into a cone-HC network model. These results suggest that desensitization of the GABAA receptor shifts the dynamic range of the HCs due to light and dark adaptation. 相似文献
105.
Ulex europaeus agglutinin I (UEA I) binding was studied in 83 patients with various neuromuscular disorders. UEA I labelled endomysial capillaries and endothelial cells of perimysial blood vessels in all the examined muscles. There was no UEA I binding to muscle fibres except for all (9) cases of distal myopathy with rimmed vacuole formation (DMRV), 1 of 5 cases of inclusion body myositis and 1 of 36 cases of inflammatory myopathies. The UEA I binding was completely eliminated by preincubation of UEA I solution with L-fucose. Using electron microscopy, the UEA I binding was localized to sarcolemma and intrasarco-plasmic membranous organelles other than mitochondria. Myosatellite cells were not labelled. These findings revealed the existence of fucosylated proteins or lipids in a subset of skeletal muscles suffering from DMRV. Biochemical identification of the fucosylated substance and further detailed study on subcellular localization of UEA I binding may yield important clues to the unknown pathogenesis of DMRV. 相似文献
106.
Tamon Ozaki Noriyuki Ito Shuhei Nakamura Jiro Kawai 《Electrical Engineering in Japan》2003,144(1):12-20
The capacitance C and dielectric dissipation factor tan δ of a water‐treed XLPE sheet sample have been measured under the application of 100 V or 1 kV at 60 Hz. The values of C and tan δ at 1 kV are much larger than those at 100 V. The value of tan δ gradually decreases with the length of exposure to a voltage of 1 kV. On the other hand, C is almost constant versus the exposure time. The results have been discussed on the basis of a model in which filling of channels interconnecting voids by water is taken into account. It has been found that the increase of C and tan δ is caused by the growth of the water‐filled channel region on the application of voltage. The gradual decrease in tan δ with the exposure time is explained by the change in the conductivity of the water‐filled channel region, as a result of which the relaxation time shifts to higher frequencies. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 144(1): 12–20, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10160 相似文献
107.
S Nishikawa T Sonoki T Kasahara T Obi S Kubota S Kawai N Morohoshi Y Katayama 《Canadian Metallurgical Quarterly》1998,64(3):836-842
A growing body of evidence supports the existence of a tissue-based renin-angiotensin system (RAS) in the vasculature, but the functional capacity of vascular RAS was not investigated in humans. In 28 normotensive healthy control subjects, the metabolism of angiotensins through vascular tissue was investigated in normal, low, and high sodium diets by the measurement of arterial-venous gradient of endogenous angiotensin (Ang) I and Ang II in two different vascular beds (forearm and leg), combined with the study of 125I-Ang I and 125I-Ang II kinetics. In normal sodium diet subjects, forearm vascular tissue extracted 36+/-6% of 125I-Ang I and 30+/-5% of 125I-Ang II and added 14.9+/-5.1 fmol x 100 mL(-1) x min(-1) of de novo formed Ang I and 6.2+/-2.8 fmol x 100 mL(-1) x min(-1) of Ang II to antecubital venous blood. Fractional conversion of 125I-Ang I through forearm vascular tissue was about 12%. Low sodium diet increased (P<.01) plasma renin activity, whereas de novo Ang I and Ang II formation by forearm vascular tissue became undetectable. Angiotensin degradation (33+/-7% for Ang I and 30+/-7% for Ang II) was unchanged, and vascular fractional conversion of 125I-Ang I decreased from 12% to 6% (P<.01). In high sodium diet subjects, plasma renin activity decreased, and de novo Ang I and Ang II formation by forearm vascular tissue increased to 22 and 14 fmol x 100 mL(-1) x min(-1), respectively (P<.01). Angiotensin degradation did not significantly change, whereas fractional conversion of 125I-Ang I increased from 12% to 20% (P<.01). Leg vascular tissue functional activities of RAS paralleled those of forearm vascular tissue both at baseline and during different sodium intake. These results provide consistent evidence for the existence of a functional tissue-based RAS in vascular tissue of humans. The opposite changes of plasma renin activity and vascular angiotensin formation indicate that vascular RAS is independent from but related to circulating RAS. 相似文献
108.
Morimoto M. Orihara K. Mutoh N. Toyoda A. Ohbo M. Kawakami Y. Nakano T. Chiba K. Kawai S. Hatano K. Arai K. Nishimura M. Nakashiba Y. Kohno A. Akiyama I. Teranishi N. Hokari Y. 《Electron Devices, IEEE Transactions on》1995,42(1):50-57
A 1-inch 2-million pixel FIT-CCD image sensor for HDTV has been developed, which features a tungsten photo-shield and horizontal CCD (H-CCD) shunt wiring. Tungsten photo-shield, which has low reflectance and good step coverage characteristics, reduces smear level to -110 dB, combined with a frame-interline-transfer (FIT) scheme. The tungsten photo-shield also acts as a shunt busline, supplying transfer pulses to vertical CCD (V-CCD) electrodes, so that a 1.2×10ˆ5 electron charge handling capability is obtained at a frame transfer frequency of 1 MHz. Newly developed H-CCD shunt wiring suppresses vertical line pair FPN, even with smaller transfer pulse amplitudes. H-CCD shunt wiring also helps reduce power consumption in the H-CCD by 2/3 as compared to that achieved with conventional wiring 相似文献
109.
Remanent magnetism of sintered diamond with cobalt has been measured with an astatic magnetometer. The results of measurements show that the intensity of remanent magnetism strongly depends on Knoop microhardness value. It is also found, from alternating field demagnetization experiment, that a specimen with higher intensity of magnetization has good magnetic stability. 相似文献
110.