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21.
Abdul Manaf Hashim Seiya Kasai Kouichi Iizuka Tamotsu Hashizume Hideki Hasegawa 《Microelectronics Journal》2007,38(12):1268-1272
Theoretical analysis of potential distribution in the interdigital-gated high electron mobility transistor (HEMT) plasma wave device was carried out. The dc I–V characteristics of capacitively coupled interdigital structure showed that uniformity of electric field under the interdigital gates was improved compared to the dc-connected interdigital gate structure. Admittance measurements of capacitively coupled interdigital gate structure in the microwave region of 10–40 GHz showed the conductance modulation by drain–source voltage. These results indicate the existence of plasma wave interactions. 相似文献
22.
Yizhi Ren Mingchu Li Yang Xiang Yongrui Cui Kouichi Sakurai 《The Journal of supercomputing》2013,63(1):171-190
Reputation systems are very useful in large online communities in which users may frequently have the opportunity to interact with users with whom they have no prior experience. Recently, how to enhance the cooperative behaviors in the reputation system has become to one of the key open issues. Emerging schemes focused on developing efficient reward and punishment mechanisms or capturing the social or economic properties of participants. However, whether this kind of method can work widely or not has been hard to prove until now. Research in evolutionary game theory shows that group selection (or multilevel selection) can favor the cooperative behavior in the finite population. Furthermore, some recent works give fundamental conditions for the evolution of cooperation by group selection. In the paper, we extend the original group selection theory and propose a group-based scheme to enhance cooperation for online reputation systems. Related concepts are defined to capture the social structure and ties among participants in reputation system, e.g., group, assortativity, etc. Also, we use a Fermi distribution function to reflect the bounded rationality of participants and the existence of stochastic factors in evolutionary process. Extended simulations show that our scheme can enhance cooperation and improve the average performance of participants (e.g. payoff) in reputation system. 相似文献
23.
Masahiro Kishida Ken-ichiro Ichiki Toshiaki Hanaoka Hideo Nagata Katsuhiko Wakabayashi 《Catalysis Today》1998,45(1-4):203-208
It was previously found that the silica-supported rhodium catalyst prepared using water-in-oil microemulsion had rhodium particles partly, or wholly, embedded in silica. In this work, consequently, we investigated the effect of hydrolysis conditions of tetraethylorthosilicate, employed as the source of silica, on the atomic ratio of surface rhodium in contact with the gas phase, to total surface rhodium of nanoparticles. This ratio is denoted as R in this paper. R became higher when the catalyst was prepared under the following hydrolysis conditions: a shorter hydrolysis time and a smaller amount of tetraethylorthosilicate. On the other hand, R showed the minimum value when the water content in the preparation solution was 33 vol%. From these results, it is demonstrated that it was important to form silica as early as possible in hydrolysis of TEOS in order to increase R values. In addition, the effect of R on the catalytic behavior in CO hydrogenation was investigated. At R values below 30%, the turnover frequencies increased with a decrease in R. 相似文献
24.
Takahiro Kawashima Tsuyoshi Kimura Takayuki Shibata Akio Kishida Takashi Mineta Eiji Makino 《Microelectronic Engineering》2010,87(5-8):704-707
In order to realize cellular network analysis on a chip-based system, our group has been developing a patterned cell culture microdevice with pillars in an array for tapping cells into space surrounded by the pillars. The pillar structures has advantages to trap both adhesive and non-adhesive cells and to precisely control positions of cells and distances between cells for understanding effects of various cell patterns on functions of a cellular network such as cell proliferation, differentiation, and network formation. In this paper, HeLa cell cultivation with the patterned cell culture microdevice having a pillar array fabricated by dry film of thick negative photoresist SU-8 on a glass substrate was executed as a feasibility study on a cellular network analysis. The results revealed that the device performance was found to be enough to culture HeLa cells for more than 48 h. In addition, relative extensibility of blocks of multiple cells compared with single cells tapped on the device was observed. Thus, the patterned cell culture microdevice proposed here could be applicable to analysis of cellular functions. 相似文献
25.
In this short paper,we have treated the aerodynamic performance of micro downwind rotor with coning soft blades experimentally.The test wind rotor has the tip diameter of 1.5 m and three two-dimensional NACA0018 blades of 0.15 m chord whose material is light,soft and pliable foam plastic for perfect safety.From the wind tunnel test,it is realized that the performance is manageable by the coning angle of the rotor blade.In the present case,an improvement of the performance in lower wind speeds is achieved by... 相似文献
26.
Kouichi Asakura Ayuko Iida Ryoichi Kitagata Atsushi Yoshida Shuichi Osanai Akihiro Kuroda 《Journal of surfactants and detergents》2001,4(4):375-378
Adsorption properties of two types of dimethylpolysiloxane backbone derivatives, perfluoroalkyl polyoxyethylenated dimethylpolysiloxane
(FPD) and polyoxyethylenated dimethylpolysiloxane (PD), onto keratin surfaces were investigated. Both polymers are amphiphilic,
since they possess hydrophilic polyoxyethylene groups. FPD contains a perfluoroalkyl group that provides both water-and oil-repellent
properties, whereas PD lacks these groups. Adsorption properties of these polymers onto keratin surfaces are considered a
good index to evaluate these compounds as nonionics used in hair-coating agents, since keratin is a major component of hair.
FPD was more likely to be adsorbed and less likely to be eliminated from the keratin surface than PD. Once FPD had been adsorbed
onto the keratin surface, it was very slowly washed from the surface when it was immersed in stationary water, whereas PD
polymers were quickly washed from the keratin surface. Even in running water, rapid elimination of FPD was not observed. The
strong resistance to loss of FPD after washing with a large quantity of water may be due to the water-repellent nature of
the perfluoroalkyl groups. As a comparison, FPD adsorption onto a glass surface was also investigated. The affinity to the
glass surface was found to be less than to the keratin surface. 相似文献
27.
Jifei Jia Eishi Tanabe Peng Wang Kouichi Ito Hiroyuki Morioka Ye Wang Tetsuya Shishido Katsuomi Takehira 《Catalysis Letters》2001,76(3-4):183-192
A solid phase crystallization (spc) method was applied for the preparation of SrTiO3-supported Ni catalysts and compared to the impregnation (imp) method. spc-Ni0.2/SrTiO3 has highly dispersed and stable Ni metal particles resulting in higher activity and higher sustainability against coking than imp-Ni0.2/SrTiO3 in the partial oxidation of CH4. Both catalysts were tested for the CH4 pyrolysis in order to elucidate the catalytic nature against coking of spc-Ni0.2/SrTiO3. The amount of carbon and the rate of H2 formation were similar over both catalysts at both 773 and 1073 K. On both catalysts, CH4 continuously decomposed at 773 K, while the rate of CH4 pyrolysis quickly decreased at 1073 K. Fibrous carbons grew up with a Ni metal particle on the tip of the fiber at 773 K, while carbon balls and short carbon fibers with a Ni metal particle encapsulated inside formed and no sufficient growth of the fiber was observed at 1073 K. The carbon species formed at 773 K was hydrogenated completely to CH4 around 873 K, while the hydrogenation of that formed at 1073 K needed higher temperature around 1073 K. However, the carbon species formed on both the catalysts at either 773 or 1073 K was completely oxidized around 773 K. Thus, judging from the anti-coking nature, the behaviors in the CH4 pyrolysis are similar over both catalysts, nonetheless spc-Ni0.2/SrTiO3 was far superior to imp-Ni0.2/SrTiO3 in the CH4 oxidation. It is likely that the high sustainability against coking of spc-Ni0.2/SrTiO3 is not due to its intrinsic nature suppressing the coking but due to its high activity of reforming which can quickly eliminate the carbon formed on the catalyst surface. 相似文献
28.
Kouichi Kamiuto 《Applied Energy》1986,23(4):297-305
Two design criteria for unevacuated horizontal multi-layer insulation systems, with equal spacings of the intermediate plates yielding the minimum heat transfer rate, are described. 相似文献
29.
STATEMENT OF PROBLEM: The surgical and restorative procedures at the posterior region of the maxilla and the mandible present a complex task in the treatment of partially edentulous patients. PURPOSE: The purpose of this study was to investigate the applicability of short hydroxylapatite-coated dental implants to the posterior mandible of partially edentulous patients. MATERIAL AND METHODS: Eight and 11 mm implants were evaluated as to their cumulative survival rate, clinical status (plaque index, gingival index, probing depth), and marginal bone loss over a 5-year period. RESULTS AND CONCLUSIONS: The verified overall cumulative survival rate was 94% for implants and 91% for prostheses. These results suggest predictable success for the application of short implants to the posterior mandible. 相似文献
30.
Kazuaki Sasaki Michiya Kishida Yutaka Ekida 《International journal for numerical methods in engineering》2002,54(5):671-683
In this paper, a finite element dislocation model is proposed, based on well‐known mathematical dislocation model. As application examples, the stress distributions around an edge dislocation in infinite homogeneous and inhomogeneous regions are calculated and compared with the analytical results. The FEM results coincide well with the exact solutions. The results show an applicability and a usefulness of finite element dislocation model, and further, a possibility of analysing a dislocation problem in finite region with complicated shapes and boundary conditions. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献