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721.
Seiji Kasahara Shinji Kubo Ryutaro Hino Kaoru Onuki Mikihiro Nomura Shin-ichi Nakao 《International Journal of Hydrogen Energy》2007
The Japan Atomic Energy Agency (JAEA) is performing research and development on the thermochemical water-splitting iodine–sulfur (IS) process for hydrogen production with the use of heat (temperatures close to 1000 °C) from a nuclear reactor process plant. Such temperatures can be supplied by a High Temperature Gas-cooled Reactor (HTGR) process. JAEA's activity covers the control of the process for continuous hydrogen production, processing procedures for hydrogen iodide (HI) decomposition, and a preliminary screening of corrosion resistant process materials. The present status of the R&D program is reported herein, with particular attention to flowsheet studies of the process using membranes for the HI processing. 相似文献
722.
Onishi M Koga T Morita R Nakamura Y Nakamura T Shimoda C Takegawa K Hirata A Fukui Y 《Yeast (Chichester, England)》2003,20(3):193-206
Phosphatidylinositol (PI) 3-kinase (encoded by the pik3(+) gene) in Schizosaccharomyces pombe has been identified as a homologue of VPS34p, a protein required for proper vesicular protein sorting. The clone defective in this protein carries enlarged vacuoles and exhibits sensitivity to high temperature or high ion concentration. The effect of disruption of pik3(+) on sporulation of Sz. pombe was examined. The diploid cells underwent G(1) arrest and meiosis. However, the spores formed by the deltapik3 cells were not viable. Electron-microscopic analysis revealed that the growth of the forespore membrane of deltapik3 cells was not correctly orientated, failing to engulf the nucleus or forming extremely small spores, as was confirmed by the use of Spo3p-GFP and GFP-Psy1p, which are markers of the forespore membrane. The coating materials found along the forespore membrane of the wild-type were greatly reduced in these cells. PI 3-P, the product of Pik3p, was detected on the forespore membrane, suggesting that PI 3-P-dependent vesicle transport may take place in formation of the forespore membrane. Misshaped forespore membrane, accumulation of vesicles, formation of small non-viable spores, and suppression by over expression of Psy1p were the phenotypes commonly seen in deltapik3 and deltaspo3 cells, suggesting a relationship between the functions of Pik3p and Spo3p in formation of the forespore membrane in Sz. pombe. 相似文献
723.
Electron-doped alpha-rhombohedral boron (alpha-r-B) crystals were synthesized by Li- and Mg-dopings. The doped alpha-r-B particles showed a shiny metallic colour, though non-doped alpha-r-B crystals showed a dark red colour (red boron). The electronic structures of doped alpha-r-B single crystals were examined by a high energy-resolution electron energy-loss spectroscopy microscope. Boron 1s electron-excitation spectra, which show the density of states of the conduction bands, of Li-doped alpha-r-B showed a chemical shift toward a smaller binding-energy side, indicating a charge transfer from the doped atoms to alpha-r-B. These spectra also showed a sharp intensity increase at the onset with a width of an energy resolution of the experiment. The sharp intensity increase may be assigned to a Fermi edge produced by the electron doping. The spectra of Mg-doped alpha-r-B showed a chemical shift indicating an electron doping, but did not show the presence of a Fermi edge. 相似文献
724.
Jun Wu Mianxiong Dong Kaoru Ota Zhenyu Zhou Bin Duan 《Wireless Personal Communications》2014,75(3):1787-1808
Data access control within smart grids is a challenging issue because of the environmental noise and interferences. On one hand side, fine-grained data access control is essential because illegal access to the sensitive data may cause disastrous implications and/or be prohibited by the law. On the other hand, fault tolerance of the access control is very important, because of the potential impacts (implied by the errors) which could be significantly more serious than the ones regarding general data. In particular, control bits corruption could invalidate the security operation. To address the above challenges, this paper proposes a dedicated data access control scheme that is able to enforce fine-grained access control and resist against the corruptions implied by the noisy channels and the environmental interferences. The proposed scheme exploits a state-of-the-art cryptographic primitive called Fuzzy identity-based encryption with the lattice based access control and dedicated error-correction coding. We evaluate our proposed scheme by extensive simulations in terms of error correcting capability and energy consumption and results show the efficiency and feasibility of the proposed scheme. To our best knowledge, this paper is the first which addresses fault tolerant fine-grained data access control for smart grid. 相似文献
725.
Quang-Duy Dao Tetsuro Hori Kaoru Fukumura Tetsuya Masuda Toshiya Kamikado Akihiko Fujii Yo Shimizu Masanori Ozaki 《Organic Electronics》2013,14(10):2628-2634
A study on the effects of processing additives on the nanoscale phase separation, crystallization, and photovoltaic performance of bulk heterojunction (BHJ) thin films made of 1,4,8,11,15,18,22,25-octahexylphthalocyanine (C6PcH2) and [6,6]-phenyl-C61 butyric acid methyl ester (PCBM) via spin-casting for photovoltaic applications is reported. By incorporating various solvents as processing additives to a volume of a few percent, the separation of donor and acceptor phases in C6PcH2:PCBM thin films, which discussed by taking the photoluminescence quenching, Davydov splitting at the Q-band of the absorbance spectra and the surface nanomorphology into consideration, is improved, and the crystallinity of the discotic C6PcH2 molecules with hexagonal structures is reinforced. Photovoltaic cells with the optimum phase-separated BHJ materials and high crystallinity of the discotic C6PcH2 molecules are demonstrated to have a power conversion efficiency of 4.2%. 相似文献
726.
Kim S Oshima Y Sawada H Kaneyama T Kondo Y Takeguchi M Nakayama Y Tanishiro Y Takayanagi K 《Journal of electron microscopy》2011,60(2):109-116
Annular dark-field scanning transmission electron microscope (ADF-STEM) images of an Si (001) crystal were obtained by using an aberration-corrected electron microscope, at 30-mrad convergent probe and cold field-emission gun at 300?kV. The intensity of ADF-STEM images, that is, the number of scattered electrons relative to the incident electrons, obtained for specimen thickness from 10 to 50?nm was compared quantitatively with absorptive multi-slice simulation. The column and background intensities were analyzed by column-by-column two-dimensional Gaussian fitting. These intensities were found to increase linearly with the sample thicknesses. However, the simulated image gave higher column intensity and lower background intensity for all the sample thickness. We found that experimental images were reproduced by the simulation with Gaussian convolution of 70?pm full-width at half-maximum for all the sample thicknesses from 10 to 50?nm. The possible factors accounted for this Gaussian convolution is discussed. 相似文献
727.
Takahashi M. Nishikawa T. Hamada M. Takayanagi T. Arakida H. Machida N. Yamamoto H. Fujiyoshi T. Ohashi Y. Yamagishi O. Samata T. Asano A. Terazawa T. Ohmori K. Watanabe Y. Nakamura H. Minami S. Kuroda T. Furuyama T. 《Solid-State Circuits, IEEE Journal of》2000,35(11):1713-1721
A 240-mW single-chip MPEG-4 videophone LSI with a 16-Mb embedded DRAM is fabricated utilizing a 0.25-μm CMOS triple-well quad-metal technology. The videophone LSI is applied to the 3GPP 3G-324M video-telephony standard for IMT-2000, and implements the MPEG-4 video SPL1 codec, the AMR speech codec, and the ITU-T H.223 Annex B multiplexing/demultiplexing at the same time. Three 16-bit multimedia-extended RISC processors, dedicated hardware accelerators, and a 16-Mb embedded DRAM are integrated on a 10.84 mm×10.84 mm die. It also integrates camera, display, audio, and network interfaces required for a mobile video-phone terminal. In addition to conventional low-power techniques, such as clock gating and parallel operation, some new low-power techniques are also employed. These include an embedded DRAM with optimized configuration, a low-power motion estimator, and the adoption of the variable-threshold voltage CMOS (VT-CMOS). The MPEG-4 videophone LSI consumes 240 mW at 60 MHz, which is only 22% of that for a conventional multichip design. Variable threshold voltage CMOS reduces standby leakage current to 26 μA, which is only 17% of that for the conventional CMOS design 相似文献
728.
Kenji Katayama Kozo Komae Kaoru Kohyama Tsuneo Kato Seiji Tamiya Katsumi Komaki 《Starch - St?rke》2002,54(2):51-57
A new sweet potato breeding line, Kanto 116, was developed, featuring low gelatinization temperature and an altered starch fine structure. Starch granules from Kanto 116 showed an abnormal morphology characterized by cracking into granules. Starch content, amylose content and tuberous root appearance of Kanto 116 were similar to those of the control and the parents. Pasting temperatures of Kanto 116 starch determined by the Rapid Visco Analyser were 51.4 — 52.6 °C, approximately 20 °C lower than those of the control and parents starches. Onset, peak, and conclusion temperature of gelatinization, and gelatinization enthalpy of Kanto 116 starch determined by differential scanning calorimetry were 39.0 °C, 46.9 °C, 64.8 °C, and 8.8 J/g, respectively, and much lower than those of the control and parents starches. The chain‐length distribution of the amylopectin molecules, determined by high‐performance anion‐exchange chromatography, showed that Kanto 116 starch had a higher proportion of short chains (DP 6 — 11) and a lower proportion of chains between DP 12 — 28 than control and parent starches. The debranched β‐limit dextrin of Kanto 116 starch also showed that the proportion of both short and long B1 chains was different from those of the control and parents starches. 相似文献
729.
Eloy Gonzales Shingo Mabu Karla Taboada Kaoru Shimada Kotaro Hirasawa 《IEEJ Transactions on Electrical and Electronic Engineering》2011,6(5):431-440
During the last years, several association rule‐based classification methods have been proposed, these algorithms may quickly generate accurate rules. However, the generated rules are often very large in terms of the number of rules and usually complex and hardly understandable for users. Among all the rules generated by the algorithms, only some of them are likely to be of any interest to the domain expert analyzing the data. Most of the rules are either redundant, irrelevant or obvious. In this paper, a new method for selecting the interesting class association rules is proposed by an evolutionary method named genetic relation algorithm. The algorithm evaluates the relevance and interestingness of the discovered association rules by the relationships between the rules in each generation using a specific measure of distance among them giving a reduced set of rules as the result in the final generation. This small rule set has the following properties: (i) accurate as it has at least the same classification accuracy as the complete association rule set, (ii) interesting because of the diversity of rules and (iii) comprehensible because it is more understandable for the users as the number of attributes involved in the rules is also small. The efficiency of the proposed method is compared with other conventional methods including genetic network programming‐based mining using ten databases and the experimental results show that it outperforms others keeping a good balance between the classification accuracy and the comprehensibility of the rules. © 2011 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献