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721.
Hydrothermal synthesis of K4Nb6O17 总被引:5,自引:0,他引:5
Satoshi Uchida Yuichi Inoue Yoshinobu Fujishiro Tsugio Sato 《Journal of Materials Science》1998,33(21):5125-5129
A new approach for the synthesis of K4Nb6O17.3H2O by hydrothermal method was examined using different alkaline solutions such as Nb2O5-KOH-NaOH-H2O, Nb2O5-KOH-NH4OH-H2O and Nb2O5-KOH-H2O. K4Nb6O17.3H2O was formed as single phase in Nb2O5-KOH-H2O system in the region of KOH concentration 1.0-1.5 m and temperature 220-285°C. KNbO3 was also formed as single phase in 3.0 m KOH solutions above 250°C. Addition of methanol was useful to decrease the particle size and increase the specific surface area of K4Nb6O17.3H2O. 相似文献
722.
Zhiwen Yu Zhiyong Yu Xingshe Zhou Yuichi Nakamura 《Personal and Ubiquitous Computing》2010,14(8):695-702
Group social dynamics is crucial for determining whether a meeting was well organized and the conclusion well reasoned. In
this paper, we propose multimodal approaches for sensing, recognition and browsing of social dynamics, specifically human
semantic interactions and group interests in small group meetings. Unlike physical interactions (e.g., turn-taking and addressing),
the human interactions considered here are incorporated with semantics, i.e., user intention or attitude toward a topic. Group
interests are defined as episodes in which participants engaged in an emphatic and heated discussion. We adopt multiple sensors,
such as video cameras, microphones and motion sensors for meeting capture. Multimodal methods are proposed for human interaction
recognition and group interest recognition based on a variety of features. A graphical user interface, the MMBrowser, is presented
for browsing group social dynamics. Experimental results have demonstrated the feasibility of the proposed approaches. 相似文献
723.
Yuichi Motoyama Hiroki Takahashi Yuki Inoue Keita Shinji Makoto Yoshida 《Journal of Materials Processing Technology》2013,213(2):238-244
The load on flange castings in sand molds was gradually increased beginning from the end of the solidification process until the final cooling stage. The maximum tensile load on the flange castings in furan sand molds was larger than that of the flange castings in green sand molds. With the furan sand mold, permanent deformation in the flange castings occurred beginning from the end of the solidification process until reaching a temperature of approximately 250 °C. The mechanical interaction between the casting and the sand mold should be considered for more accurate stress calculations, particularly in furan sand molds. 相似文献
724.
Masahiro Wasai Satoshi Murakawa Yuta Tamura Yuichiro Wada Yuki Aoki Ryuji Nomura Yuichi Okuda 《Journal of Low Temperature Physics》2010,158(1-2):268-274
We measured transverse acoustic impedance Z of normal fluid 3He at 46.6 MHz on a surface coated with a thin 4He film. The real component of the impedance, Z′, in the coated samples deviates from Z′ in the pure 3He in the low temperature region. Z′ on the coated samples is almost identical with Z′ in the pure sample at high temperature and gradually deviates below a particular temperature T onset . T onset is possibly the superfluid onset temperature of the 4He film pressurized by the bulk liquid 3He. The gradual decrease in Z′ means that the superfluid component in 4He film increases gradually, which is expected from the dynamic KT transition at high frequency. The thicker is the film, the higher is the T onset . The range of T onset we observed was between 40 and 160 mK. This is much lower than that at the saturated vapor pressure. Suppression of T onset achieved by the applied pressure from bulk liquid 3He was presumably caused by the dissolved 3He in the film, thickening of the inert layers and/or by the strong correlation effect. The result shows that the specularity of 3He quasiparticle scattering is strongly affected by superfluidity of the 4He film. 相似文献
725.
The asymmetric traveling salesman problem (ATSP) is one of the most important combinatorial optimization problems. It allows us to solve, either directly or through a transformation, many real-world problems. We present in this paper a new competitive genetic algorithm to solve this problem. This algorithm has been checked on a set of 153 benchmark instances with known optimal solution and it outperforms the results obtained with previous ATSP heuristic methods. 相似文献
726.
Motoyuki?Ozeki Shunichi?Maeda Kanako?Obata Yuichi?NakamuraEmail author 《Multimedia Tools and Applications》2009,44(3):433-448
In this paper, we propose the “Virtual Assistant,” a novel framework for supporting knowledge capturing in videos. The Virtual
Assistant is an artificial agent that simulates a human assistant shown in TV programs and prompts users to provide feedback
by asking questions. This framework ensures that sufficient information is provided in the captured content while users interact
in a natural and enjoyable way with the agent. We developed a prototype agent based on a chatbot-like approach and applied
it to a daily cooking scene. Experimental results demonstrate the potential of the Virtual Assistant framework, as it allows
a person to provide feedback easily with few interruptions and elicits a variety of useful information.
Motoyuki Ozeki received his B.E, M.E. and Ph.D. degrees in engineering from University of Tsukuba, in 2000 and 2005, respectively. He worked as an assistant professor at Kyoto University since 2005. He is currently an assistant professor at Kyoto Institute of Technology. His research interests are in the areas of human-agent interaction and cognitive science. Shunichi Maeda received his B.E and M.E. degrees in electronical engineering from Kyoto University, in 2008. He is currently working in Patent Office (KAJI-SUHARA & ASSOCIATES). Kanako Obata received her B.E. degree in economics from Osaka Prefecture University in2004. She is currently an educational assistant at Kyoto University as since 2004. Her research interests are human-communication and cooking. Yuichi Nakamura received his BE degree in 1985, his ME and PhD degrees in electronical engineering from Kyoto University in 1987 and 1992, respectively. He worked as assistant professor at University of Tsukuba since 1993 and as associate professor since 1999. He is currently a professor at Kyoto University. His research interests and activities include human-computer interactions, video analysis, and video utilization for knowledge sources. 相似文献
Yuichi NakamuraEmail: URL: http://www.ccm.media.kyoto-u.ac.jp/index.php |
Motoyuki Ozeki received his B.E, M.E. and Ph.D. degrees in engineering from University of Tsukuba, in 2000 and 2005, respectively. He worked as an assistant professor at Kyoto University since 2005. He is currently an assistant professor at Kyoto Institute of Technology. His research interests are in the areas of human-agent interaction and cognitive science. Shunichi Maeda received his B.E and M.E. degrees in electronical engineering from Kyoto University, in 2008. He is currently working in Patent Office (KAJI-SUHARA & ASSOCIATES). Kanako Obata received her B.E. degree in economics from Osaka Prefecture University in2004. She is currently an educational assistant at Kyoto University as since 2004. Her research interests are human-communication and cooking. Yuichi Nakamura received his BE degree in 1985, his ME and PhD degrees in electronical engineering from Kyoto University in 1987 and 1992, respectively. He worked as assistant professor at University of Tsukuba since 1993 and as associate professor since 1999. He is currently a professor at Kyoto University. His research interests and activities include human-computer interactions, video analysis, and video utilization for knowledge sources. 相似文献
727.
Integrated structure of PMMA microchannels for DNA separation by microchip capillary electrophoresis
Yuichi Utsumi Tomohiro Ikeda Megumi Minamitani Kazuo Suwa 《Microsystem Technologies》2008,14(9-11):1461-1466
We proposed and fabricated an integrated structure of microchannels consists of three different functional PMMA layers for post-genome analysis, gene diagnosis, and screenings of useful materials for pharmaceutical. This integrated structure with 96 microchip capillary electrophoresis units in one chip is characterized as the simple structure with low cost and new aspects of the serial unit bio-chemical operation from DNA amplification to their analysis using microchip capillary electrophoresis. The design of the structure was performed using computational fluid dynamics, heat transmission, and electrophoresis simulation. To improve DNA separation resolution, microchannel with narrow width at the corner was adapted. The deep X-ray lithography process using synchrotron radiation “New SUBARU”, nano-imprint, and fusion bonding without bonding adhesive was applied for the fabrication of the integrated structure of microchannels. It was demonstrated that the proposed integrated structure of microchannels results in a good performance of the on-chip DNA amplification and separation in a small MCE unit area of 9 mm × 9 mm. 相似文献
728.
Preparation of Highly Dispersed Ultrafine Barium Titanate Powder by Using Microbial-Derived Surfactant 总被引:1,自引:0,他引:1
Hidehiro Kamiya Kenjiro Gomi Yuichi Iida Kenji Tanaka Takashi Yoshiyasu Toshihito Kakiuchi 《Journal of the American Ceramic Society》2003,86(12):2011-2018
To uniformly disperse ultrafine BaTiO3 particles with a stoichiometric composition and several tens of nanometers in diameter to primary particles during the sol–gel synthesis process, a new aqueous surfactant with a high hydrophilic group density and special cis-structure was prepared from a microbial product and added to solution before the sol–gel synthesis reaction. Because of the rapid formation of large and porous aggregates which were 30–50 μm in diameter in suspension without addition of this unique structural surfactant, the prepared ultrafine BaTiO3 particles caused rapid sedimentation in suspension. The addition of the surfactant in the range of 7.1 wt% for the synthesized BaTiO3 particles made it possible to decrease the size of the aggregates in suspension as well as the sedimentation velocity while maintaining the stoichiometric composition. The optimum additive content to obtain the minimum aggregate size of about 100–200 nm in diameter and the highest dispersion stability in suspension while maintaining the stoichiometric composition of prepared ultrafine BaTiO3 particles without other phases was determined at about 7.1 wt%. Because the excess addition of this surfactant at more than 8.5 wt% inhibited the uniform synthesis of BaTiO3 particles, an amorphous phase with a highly specific surface area and a BaCO3 phase formed in the synthesized particles. 相似文献
729.
Exfoliation-reduction of VOPO4 · 2H2O in a mixed alcohol consisting of 2-butanol and ethanol, followed by the thermal treatment in the presence of n-butane, O2, and He at 663 K for 300 h, produces novel nano-sized crystallites (~ 50 nm) of (VO)2P2O7. The nano-sized (VO)2P2O7 crystallites exhibit a high selectivity to maleic anhydride (~ 84%) for the selective oxidation of n-butane. 相似文献
730.
Methanol Synthesis from Carbon Monoxide and Hydrogen over Ceria-Supported Copper Catalyst Prepared by a Coprecipitation Method 总被引:1,自引:0,他引:1
High catalytic activity in the synthesis of methanol from carbon monoxide and hydrogen can be produced with ceria-supported copper catalysts prepared by a coprecipitation method. The activity at 468 K is comparable with that produced with commercial copper-zinc catalysts at 503-523 K, while it is still unstable. Although the reaction atmosphere is reductive, metallic copper particles on cerium oxide are oxidized during the reaction and the catalyst is activated. Hence, formation of the copper oxide species is indispensable for the appearance of the high catalytic activity. 相似文献