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101.
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
102.
Dye‐containing nonaqueous dispersions derived from methanol‐soluble polymers stabilized by block–random copolymer surfactant
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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
103.
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
104.
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
105.
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
106.
Giuseppe Pezzotti Ken'ichi Ota Yoshifumi Yamamoto Hua-Tay Lin 《Journal of the American Ceramic Society》2003,86(3):471-474
Intergranular sliding and diffusive mechanisms behind the deformation behavior of a commercially available lutetium-doped silicon nitride were investigated and discussed. A method of locating and separating phenomena critical for mechanical relaxation at elevated temperatures was applied; the method was based on low-frequency forced-vibration damping measurements. The potentiality of lutetium addition for improving the deformation resistance of silicon nitride was clearly reflected in the high-temperature damping behavior of the investigated polycrystal. Softening of intergranular lutetium silicate phases located at multigrain junctions, which resulted in a grain-boundary sliding peak, occurred at remarkably high temperatures (>1725 K). This phenomenon, partly overlapping diffusional flow, was followed by further damping relaxation with the melting of the lutetium silicates. Subsequent grain growth was also detected at temperatures >2100 K. Torsional creep results, collected up to 2100 K, consistently proved the presence of a "locking" effect by lutetium silicates with the sliding of silicon nitride grain boundaries below 1873 K. 相似文献
107.
Quantum Property Testing of Group Solvability 总被引:1,自引:0,他引:1
Testing efficiently whether a finite set Γ with a binary operation ⋅ over it, given as an oracle, is a group is a well-known
open problem in the field of property testing. Recently, Friedl, Ivanyos and Santha have made a significant step in the direction
of solving this problem by showing that it is possible to test efficiently whether the input (Γ,⋅) is an abelian group or is far, with respect to some distance, from any abelian group. In this paper, we make a step further and construct
an efficient quantum algorithm that tests whether (Γ,⋅) is a solvable group, or is far from any solvable group. More precisely, the number of queries used by our algorithm is polylogarithmic
in the size of the set Γ. 相似文献
108.
109.
Tomoichiro Okamoto Yoshifumi Tsutai 《Science and Technology of Advanced Materials》2013,14(2):195-198
A hot spot, which is a local area glowing orange, appears in a GdBa2Cu3O7–δ ceramic rod when a voltage exceeding a certain value is applied to the rod at room temperature. The rod with the hot spot shows various functional characteristics that give rise to applications in devices. We found that the hot spot created a sponge-like structure in the rod. The elemental map revealed that the sponge-like structure was composed of Gd2BaCuO5 grains. The hot spot is considered to decompose GdBa2Cu3O7–δ into Gd2BaCuO5 and liquid phase, and the liquid phase moves toward the periphery of the rod, leaving sponge-like structure composed of Gd2BaCuO5 grains. The novel sponge-like structure created in the GdBa2Cu3O7–δ rod by the hot spot may bring about new applications for magnetic separations of fluids. 相似文献
110.
Jun-ichi Kadokawa Yoshifumi Nakamura Yousuke Sasaki Yoshiro Kaneko Takehiro Nishikawa 《Polymer Bulletin》2008,60(1):57-68
Summary This paper reports chemoenzymatic synthesis of amylose-grafted polyacetylenes according to the following reaction manners.
Polymerization of a N-propargylamide monomer having a maltooligosacchairde chain was firstly carried out using a water-soluble Rh-catalyst in water,
giving maltooligosaccharide-grafted polyacetylene. The 1H NMR spectrum of the product supported the structure of the desired polyacetylene. Then, the enzymatic chain-elongation from
the oligosaccharides of the polymer was performed using glucose-1-phosphate catalyzed by phosphorylase to give the polyacetylene
having amylose side-chains. Furthermore, copolymerization of the monomer with the other N-propargylamide monomer was performed under the conditions similar to those of homopolymerization. The phosphorylase-catalyzed
enzymatic chain-elongation of the copolymer was also carried out. The DLS measurement of the amylose-grafted polyacetylenes
in alkaline solution was conducted. 相似文献