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61.
Hiroaki Ishikawa Takehide Nomura Yasuyuki Saito Haruo Kawasaki Atsushi Okamoto Ryuta Hatakenaka 《亚洲传热研究》2011,40(3):269-285
As heat generation in satellites increases, ensuring that they are provided with sufficient radiator panel area is an important problem. Deployable radiators, with radiator panels that are deployed post‐launch in space to increase the satellite's effective radiator panel area of the satellite, are becoming an important thermal control technology. A reservoir embedded loop heat pipe (RELHP) is used in deployable radiators as a heat transport device. A deployable radiator of this type was mounted on the ETS‐VIII satellite, which was launched on December 18, 2006 and injected into a geostationary orbit. The satellite is still operating without any significant issues over two years later. This paper investigates the heat transport characteristics of an RELHP system used in a deployable radiator in a geostationary orbital environment. This system can be successfully started up in a micro gravity environment. We also found that the sub‐cooling region is shorter in a micro gravity environment than in a terrestrial gravity environment, because there is less heat leakage into the reservoir in a micro gravity environment. © 2011 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library ( wileyonlinelibrary.com/journal/htj ). DOI 10.1002/htj.20346 相似文献
62.
Masahiko Okumura Ayaka Ikado Yasuhiro Saito Hideyuki Aoki Takatoshi Miura Yoshiaki Kawakami 《International Journal of Hydrogen Energy》2012
In-situ and transient visualizations of the packing structure of a hydrogen storage alloy bed are carried out using an X-ray computed tomography (CT) system. The packing structure is clearly observed on the microscale using the CT system. When the alloy bed is subjected to hydrogen absorption–desorption cycles, the pulverization progresses from the lower to the upper regions of the bed. After several hydrogen absorption–desorption cycles, the packing structure in the lower region of the bed changes and the microstructural void decreases slightly. Based on these results, we propose a pulverization mechanism of the packed bed in which the friction between particles affects the pulverization process. 相似文献
63.
64.
Taizo Miyachi Susumu Kunifuji Hajime Kitakami Koichi Furukawa Akikazu Takeuchi Haruo Yokota 《New Generation Computing》1984,2(4):385-404
In this paper we consider a deductive question-answering system for relational databases as a logic database system, and propose a knowledge assimilation method suitable for such a system. The concept of knowledge assimilation for deductive logic is constructed in an implementable form based on the notion of amalgamating object language and metalanguage. This concept calls for checks to be conducted on four subconcepts, provability, contradiction, redundancy, independency, and their corresponding internal database updates. We have implemented this logic database knowledge assimilation program in PROLOG, a logic programming language, and have found PROLOG suitable for knowledge assimilation implementation. 相似文献
65.
Nakamura Masahiko Suzuki Yutaka Tomoda Haruo 《IEEE transactions on bio-medical engineering》1982,(7):523-530
A quantitative approach for correction of background counts is described for determination of the left ventricular ejection fraction from first-pass radionuclide angiocardiography. First, the method is investigated theoretically and numerically using a mathematical model. It is demonstrated that the ejection fraction can be estimated relatively well, even in a noisy situation. Second, the method is applied to the left ventricular time-activity curves from two different regions of interest, the carefully selected and the laxly selected, and these are compared to each other. Good agreement (correlation coefficient = 0.96) for 20 patients was obtained between the ejection fractions from the carefully selected region of interest and those from the laxly selected one. 相似文献
66.
We have developed a high-throughput deep-ultraviolet (DUV) Raman microspectrometer with excitation from a continuous wave (cw) laser operated at 244 nm that enables us to characterize thin surface layers of wide-gap semiconductors. This spectrometer system consists of a filter spectrometer for the rejection of stray light and a high-dispersion spectrograph combined with a liquid nitrogen cooled charge-coupled device (CCD) detector and extends the low-frequency limit of the observable spectral range down to 170 cm(-1). In the microscope we use a Cassegrain reflective objective for the collection of the scattered light and an off-axis mirror for introduction of the excitation laser light. DUV Raman spectroscopy has been applied for studying wide-gap semiconductors including SiC and AlGaN epitaxial films and shallow implanted layers of these materials. Raman spectra of various crystals have also been measured for examining the performance of this system. Resonance enhancement of Raman bands has been observed for several semiconductors, and the results are discussed. 相似文献
67.
Shoji Noda Haruo Doi Tatsumi Hioki Jun-Ichi Kawamoto Osami Kamigaito 《Journal of Materials Science》1987,22(12):4267-4273
Single-crystal alumina was implanted firstly with 400 keV Si+ and subsequently with N2
+ ions and then annealed at 1673 K in an No atmosphre. The implanted layers were characterized by means of X-ray diffraction, Rutherford backscattering-channelling of 2 MeV He+ ions, and the resonance nuclear reaction15N(p,)12C. The annealing of sapphire implanted at ambient temperature resulted in the formation of-sialon, a solid solution of-silicon nitride and alumina in the subsurface layer, while implantation at 100 K resulted in the formation of aluminium oxynitride in the surface layer. In the latter case, the implanted silicon atoms were believed not to react vxi1h the implanted nitrogen atoms but with the substrate oxygen atoms. These crystalline precipitates were found to have epitaxial relations with the sapphire substrate. 相似文献
68.
69.
Noriya Izu Haruo Kishimoto Takahisa Omata Takayuki Yao Shinya Otsuka-Yao-Matsuo 《Science and Technology of Advanced Materials》2001,2(3-4)
Electrical conductivity σt of metastable κ-CeZrO4 possessing ordered arrangement of Ce and Zr ions in a manner similar to a pyrochlore-type was measured as a function of temperature and time, and compared with tetragonal metastable t′-(Ce0.5Zr0.5)O2 and t′meta-(Ce0.5Zr0.5)O2 phases possessing random arrangement of the cations. The κ disk was prepared by reoxidizing a pyrochlore-type precursor in O2 gas at 873 K. The σt as measured for the κ-CeZrO4 was reproducible as a function of temperatures between 957 and 1190 K. At increasing temperatures above 1233 K, the σt decreased gradually with time due to the phase transition: κ→t′, and became consistent with the t′. Although the κ-CeZrO4 phase is thermodynamically less stable than the t′-(Ce0.5Zr0.5)O2, it was virtually stable up to around 1233 K. It was found from the change in the σt due to the phase transition that the σt for the metastable κ-CeZrO4 was an order of magnitude higher than that for the t′ and was similar to that for the t′meta. It was previously reported that a phase transition, t′meta→t′, occurred above 1143 K. The phase transition, κ→t′, accompanied by redistribution of the cations appeared to occur at higher temperatures than that for t′meta→t′ leaving random cation arrangement. 相似文献
70.
Jun Narumi Sosuke Miyazawa Haruo Miyata Atsuko Suzuki Shigemi Kohsaka Hiromi Kosugi 《Accident; analysis and prevention》1999,31(6):1370-629
Analysis of reports about incidental and accidental events in nursing care were made using a reliability engineering method. Unnatural working hours, such as evening duty, night duty falling next to a holiday, two consecutive night-duty shifts, and two consecutive evening-duty shifts were major factors in the occurrence of errors. In a mixed-division ward (a ward containing patients belonging to different divisions), rule-based errors happened more frequently than in a single-division ward. Also, less experienced nursing staffs made errors more frequently than experienced nursing staffs. 相似文献