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排序方式: 共有678条查询结果,搜索用时 31 毫秒
51.
Yoshihiro Imai Tadashi Tokumasu Hidehiro Nagamura Kiyoshi Miyaike Hisakazu Matsumoto Hiroshi Hasegawa Hiroshi Kusafuka Masatoyo Shibuya Ryukichi Takahashi 《Electrical Engineering in Japan》2007,160(2):30-38
In the combined‐cycle power plant generators are started by using the igniting arrangement up to the ignition rotational speed of the gas turbine. On the other hand, in the case of using the superconducting generator, it is difficult to apply the igniting arrangement used to generate electricity on the combined cycle for the structure as is. We examined the induction motor starting method for the superconducting generator by using the 70‐MW‐class quick‐response excitation superconducting model generator and the VVVF power supply. From the examination, we confirmed the ability to raise the rotational speed from 6 to 360 rpm. Moreover, it was found to be able to start 200‐MW‐class superconducting generators by the induction motor starting method with the analysis. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 160(2): 30– 38, 2007; Published online in Wiley InterScience ( www.interscience. wiley.com ). DOI 10.1002/eej.20283 相似文献
52.
K. Ohkawa S. Shimizu H. Sato T. Komaru W. Futako T. Kamiya C. M. Fortmann I. Shimizu 《Solar Energy Materials & Solar Cells》2001,66(1-4)
Stability against light soaking was studied for amorphous silicon (a-Si:H) solar cells using three different i-layers; (a) device-quality a-Si:H (standard a-Si:H) with bandgap of 1.75 eV, (b) narrow bandgap (1.55 eV) a-Si:H fabricated by Ar* chemical annealing and (c) a-Si:H(Cl) fabricated from SiH2Cl2. Both the narrow bandgap a-Si:H and the a-Si:H(Cl) solar cells showed much improved stability than that of the standard a-Si:H solar cells: e.g., fill factor of the narrow bandgap a-Si:H cell only slightly decreased from 56% to 53%, while that of the standard a-Si:H cell degraded from 62% to 51%. In addition, mobility–lifetime products of the a-Si:H(Cl) cell also exhibited improved stability than that of the standard a-Si:H solar cell. 相似文献
53.
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55.
Noninvasive Measurement of the Volume Elastic Modulus in Finger Arteries Using Photoelectric Plethysmography 总被引:2,自引:0,他引:2
Shimazu Hideaki Yamakoshi Ken-Ichi Kamiya Akira 《IEEE transactions on bio-medical engineering》1986,(8):795-798
A method for the nonivasive measurement of the volume elastic modulus (Ev) in human finger arteries was developed. The volume change ratio and pulse pressure in the arteries were simultaneously determined by a transmittance type infrared photoelectric plethysmograph and a volume oscillometric sphygmomanometer using an occlusive cuff. The Ev values could be obtained at a desired transmural pressure level of the arteries which was controlled by the cuff. A clear difference was revealed between the Ev values obtained in the fingers of two male subjects of 33 and 65 years old. The values determined by this method were compared to those calculated from pulse wave propagation velocity (Evp) obtained simultaneously in the fingers of 11 subjects. The linear regression equation was Ev = 1.31 Evp ?0.117 with a correlation coefficient r = 0.893 (n = 39). These results suggest that this should be a useful and noninvasive method of evaluating changes in arterial elasticity accompanying aging and perhaps influenced by accompanying hypertension or arteriosclerosis. 相似文献
56.
The possibility of thermal proof testing with thermal stress induced by quenching was examined. For this purpose, the bending strength and the critical temperature difference for quenching into water and quench oil for soda-lime-silica glass were measured before and after proof testing by quenching the specimens into water, ethyl alcohol, silicon oil and quench oil. Proof testing by water, ethyl alcohol and silicon oil quenching modified the distribution of the critical temperature difference as expected, but not that of the bending strength at all. It is suggested that proof testing by rapid quenching is a useful method for truncating the critical temperature difference distribution of ceramic components of heat engines and so on. 相似文献
57.
Izumi Kita Tomohiro Shibata Yuki Kamiya Daishi Kato Kazuo Kunieda Keiji Yamada Kazushi Ikeda 《Artificial Life and Robotics》2009,14(3):375-378
To increase the productivity of knowledge workers, it is necessary to manage their organization so that they are motivated
to collaborate with each other for their synergy. However, it is difficult for managers to grasp the explicit interactions
of workers in the organization all the time. Owing to advanced communications technology, and the reduced size and improved
capabilities of computers, we are able to record group behaviors as logging data in the office. The aim of this study is to
extract features of group behavior from long-range office-logging data. We apply principal component analysis to the data
matrix whose element is the mean travel velocity calculated from an individual’s trajectory per day. The results demonstrate
the feasibility of our approach, since nontrivial informative group features can be extracted. 相似文献
58.
Atsushi Satsuma Hironaka Kanbe Kannan Srinivasan Shin-ich Komai Yuichi Kamiya Tadashi Hattori 《Microporous and mesoporous materials》2008,110(2-3):528-533
Nano-sized interlayer space of lamellar vanadyl benzylphosphate was controlled by water content in starting solution. Depending on the water content, three types of lamellar vanadyl benzylphosphate having basal spacings of 1.4 nm, 1.9 nm and 2.3 nm were obtained. It was suggested that the difference in the concentrations of benzyl and hydroxyl groups in the interlayer leads to the variation of the interlayer space. 相似文献
59.
Hidehiro Yoshida Masayasu Kodo Kohei Soga Takahisa Yamamoto 《Journal of the European Ceramic Society》2012,32(12):3103-3114
The sintering behavior of Y2O3 doped with 1 mol% of a trivalent or tetravalent cation was investigated by pressureless sintering in air. Ga3+ or Ge4+-doped Y2O3 bodies exhibited higher relative densities than the undoped Y2O3, while the La3+ or Zr4+-doping suppressed the densification of Y2O3. An interdiffusion experiment was performed on the diffusion couples of polycrystalline Er2O3 and Y2O3 doped with Ni2+ or Zr4+, which are some of the most effective and least effective dopants for the improvement of the sinterability, respectively. The lattice and grain boundary diffusion coefficients of the Er3+ cation in Y2O3 were increased by the Ni2+-doping, but were decreased by the Zr4+-doping. High-resolution transmission electron microscopy observations and nano-probe X-ray energy dispersive spectroscopy analyses confirmed that the dopant cations segregate along the grain boundaries without forming an amorphous phase. The doping effect on the sinterability of Y2O3 must result from the change in the diffusivity in Y2O3. 相似文献
60.
GJ Bishop T Nomura T Yokota K Harrison T Noguchi S Fujioka S Takatsuto JD Jones Y Kamiya 《Canadian Metallurgical Quarterly》1999,96(4):1761-1766
Brassinosteroids (BRs) are steroidal plant hormones essential for normal plant growth and development. Mutants in the biosynthesis or perception of BRs are usually dwarf. The tomato Dwarf gene (D), which was predicted to encode a cytochrome P450 enzyme (P450) with homology to other P450s involved in BR biosynthesis, was cloned previously. Here, we show that DWARF catalyses the C-6 oxidation of 6-deoxocastasterone (6-deoxoCS) to castasterone (CS), the immediate precursor of brassinolide. To do this, we first confirmed that the D cDNA complemented the mutant light- and dark-grown phenotypes of the extreme dwarf (dx) allele of tomato. To identify a substrate for the DWARF enzyme, exogenous application of BR intermediates to dx plants was carried out. C-6 oxoBR intermediates enhanced hypocotyl elongation whereas the C-6 deoxoBR, 6-deoxoCS, had little effect. Quantitative analysis of endogenous BR levels in tomato showed mainly the presence of 6-deoxoBRs. Furthermore, dx plants were found to lack CS and had a high level of 6-deoxoCS in comparison to D plants that had CS and a lower level of 6-deoxoCS. Confirmation that DWARF catalyzed the C-6 oxidation of 6-deoxoCS to CS was obtained by functional expression of DWARF in yeast. In these experiments, the intermediate 6alpha-hydroxycastasterone was identified, indicating that DWARF catalyzes two steps in BR biosynthesis. These data show that DWARF is involved in the C-6 oxidation in BR biosynthesis. 相似文献