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81.
Tetsuo Uzuka Shin-Ichi Hase Yoshifumi Mochinaga Masatoshi Takeda Takeshi Miyashita Tsuyoshi Ueda 《Electrical Engineering in Japan》1996,117(3):87-101
In this paper, the authors describe the basic configuration of an RPC (Railway Static Power Conditioner), its compensation principles and successful test results (using a small model of RPC). An ac electric railway is placed under a rapidly changing single-phase load. To avoid a voltage fluctuation under single-phase loads, electric power is received from a large source. At a feeding substation, three-phase electric power is transformed into two kinds of directional single-phase feeding electric power. The authors have already proposed a static voltage compensator for the ac electric railway, called “RPC.” The RPC links a pair of feeding circuits, using two self-commutated inverters. At the substation, the RPC accommodates an active power in the directional pair of feeding circuits to balance three-phase power, and possess a reactive power to regulate a three-phase voltage fluctuation. At a sectioning post, it can compensate for voltage drop using reactive power. It can also act as an active filter to compensate for harmonics. The authors have made a small model (220 V, 20 kVA) of the RPC, and report on the test results obtained using this small model under various conditions. The results indicate that the RPC can accommodate single phase loads, such as transformers and thyristors, can handle an exciter rush current from a transformer, can compensate for harmonics, and so on. 相似文献
82.
83.
84.
85.
Yasuyuki Tsukada Hideki Sakurada Ken Mano Yoshifumi Manabe 《Annals of Mathematics and Artificial Intelligence》2016,78(2):101-129
In this paper, we exploit epistemic logic (or the modal logic of knowledge) for multiagent systems to discuss the compositionality of several privacy-related information-hiding/disclosure properties. The properties considered here are anonymity, privacy, onymity, and identity. Our initial observation reveals that anonymity/privacy properties are not necessarily sequentially compositional. This means that even though a system comprising several sequential phases satisfies a certain unlinkability property in each phase, the entire system does not always enjoy a desired unlinkability property. We show that the compositionality can be guaranteed provided that the phases of the system satisfy what we call independence assumptions. More specifically, we develop a series of theoretical case studies of what assumptions are sufficient to guarantee the sequential compositionality of various degrees of anonymity, privacy, onymity, and/or identity properties. Similar results for parallel composition are also discussed. Further, we use the probabilistic extension of epistemic logic to consider the compositionality of probabilistic anonymity/privacy. We show that the compositionality can also be guaranteed in the probabilistic setting, provided that the phases of the system satisfy a probabilistic independence assumption. 相似文献
86.
Dye‐containing nonaqueous dispersions derived from methanol‐soluble polymers stabilized by block–random copolymer surfactant 下载免费PDF全文
In this study, nonaqueous emulsion solvent evaporation was utilized to prepare nonaqueous dispersions derived from various methanol‐soluble polymers, such as polyvinylpyrrolidone (PVP), polyethylene glycol, polyvinyl acetate (PVAC), and poly(acrylic acid), using a block–random copolymer surfactant; the block–random copolymer poly(SMA)88‐b‐poly(DEAGMA15‐r‐SMA14), composed of stearyl methacrylate, and diethanolamine‐modified glycidyl methacrylate, was used to stabilize the nonaqueous emulsions of methanol containing the polymers and an isoparaffin solvent, Isopar M. In the cases without dye, all emulsions and dispersions obtained after the evaporation of methanol exhibited nanometer‐sized particles as well as good stability. For emulsions consisting of dye‐containing methanol phases, particle sizes and stability of the obtained dispersions were dependent on the nature of the methanol‐soluble polymers. The dispersions derived from PVP and PVAC, which possibly interact weakly with the block–random copolymer and dye, exhibited good stability and a small particle size, which can be applied for inkjet printing. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44671. 相似文献
87.
Tsuji Akihiko; Ikoma Takayuki; Hashimoto Emi; Matsuda Yoshiko 《Protein engineering, design & selection : PEDS》2002,15(2):123-130
PACE4, furin and PC6 are Ca2+-dependent serine endoproteasesthat belong to the subtilisin-like proprotein convertase (SPC)family. Recent reports have supported the involvement of theseenzymes in processing of growth/differentiation factors, viralreplication, activation of bacterial toxins and tumorigenesis,indicating that these enzymes are a fascinating target for therapeuticagents. In this work, we evaluated the sensitivity and selectivityof three rat 相似文献
88.
Tatsuro Ouchi Tooru Katsuura Masaya Inaba Taiji Azuma Yoshifumi Hosaka Minoru Imoto 《Polymer》1984,25(3):412-416
The polymerization of vinyl monomer initiated by an aqueous solution of poly(N,N,N-trimethyl-N-2-methacryloxyethyl)ammonium chloride (poly(Q-DMAEM-CI) has been carried out at 85°C. The effects of the amounts of vinyl monomer, poly(Q-DMAEM-CI) and water on the conversion of vinyl monomer have been studied. The overall activation energy in the polymerization of MMA is estimated as 41.9 kJ mol?1. The polymerization proceeds through a radical mechanism. The location in which the polymerization occurs is discussed. The selectivity for vinyl monomer is explained by ‘the concept of hard and soft hydrophobic areas and monomers’. 相似文献
89.
Tomokazu Yoshimura Yasuhiro Kiridoshi Yoshifumi Koide Hideto Shosenji Kunio Esumi 《Journal of surfactants and detergents》2002,5(2):159-164
N-(α-Carboxyalkyl)acrylamide telomer-type surfactants (xC
n−1
AmAc where n is alkyl chain length=6, 8, 10, 12; and x is degree of polymerization=3.3–13.1) were synthesized by the telomerization of monomer (C
n−1
AmAc) in the presence of the corresponding alkanethiol as a chain transfer agent and then investigated for their surface-active
properties. xC
n−1
AmAc telomers lowered the surface tension of aqueous solutions that were at pH 9–10. The critical micelle concentrations (CMC)
of the telomers were lower than those of the monomers with the same alkyl chain length, and the CMC values shifted to lower
concentrations with both increasing alkyl chain length and polymerization degree. xC9AmAc with x=3.3–6.3 gave the highest efficiencies in lowering the surface tension. The cross-sectional molecular areas per molecule of
xC
n−1
AmAc telomers were smaller than the values estimated on the assumption that they are assemblies of C
n−1
AmAc monomer units. The foaming abilities and the foam stabilities were both in the orders of xC7AmAc>xC9AmAc>xC5AmAc>xC11AmAc. Mixtures of aqueous solutions of xC
n−1
AmAc telomers and toluene formed oil-in-water emulsions. The emulsion-stabilizing abilities were in the orders of xC7AmAc>xC5AmAc>xC9AmAc=xC11AmAc. The addition of Ca2+ to the mixed solutions of telomers and toluene resulted in formation of water-in-oil type emulsions. Thus, the surface-active
properties of the telomers were influenced significantly by the alkyl chain length and the polymerization degree of the telomers.
In addition, these properties could be correlated with the hydrophilic-lipophilic balance (HLB); the highest surface activities
were observed by using xC
n−1
AmAc with HLB of 14–18. 相似文献
90.
从底部加热的薄流体层的对流是研究混合流体对流斑图特性的典型模型之一并已被广泛的研究.研究集中在具有弱SORET效应的混合流体行进波对流的斑图动力学方面. 利用MAC算法通过求解二维流体力学扰动方程组进行了数值模拟. 给出了具有弱SORET效应的混合流体对流的瞬态的对传波(Counterpropagating wave),Blinking行进波,向局部行进波的过渡过程,局部行进波的时空结构及定常行进波的对流场的结构,并进一步研究了斑图的动力学特性等. 相似文献