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51.
L. El Hafi S. Isobe Y. Tabuchi Y. Katsumata H. Nakamura T. Fukui 《Advanced Robotics》2020,34(3-4):157-172
Human–robot interaction during general service tasks in home or retail environment has been proven challenging, partly because (1) robots lack high-level context-based cognition and (2) humans cannot intuit the perception state of robots as they can for other humans. To solve these two problems, we present a complete robot system that has been given the highest evaluation score at the Customer Interaction Task of the Future Convenience Store Challenge at the World Robot Summit 2018, which implements several key technologies: (1) a hierarchical spatial concepts formation for general robot task planning and (2) a mixed reality interface to enable users to intuitively visualize the current state of the robot perception and naturally interact with it. The results obtained during the competition indicate that the proposed system allows both non-expert operators and end users to achieve human–robot interactions in customer service environments. Furthermore, we describe a detailed scenario including employee operation and customer interaction which serves as a set of requirements for service robots and a road map for development. The system integration and task scenario described in this paper should be helpful for groups facing customer interaction challenges and looking for a successfully deployed base to build on. 相似文献
52.
Fast chemical vapor deposition of microcrystalline silicon by applying magnetic field to hollow electrode enhanced radio frequency (rf) glow plasma has been investigated. We have already developed a plasma generation technique called hollow electrode enhanced rf glow plasma transportation (HEEPT). In this study, we equipped a HEEPT system with a hollow cylinder shaped permanent magnet around an orifice prepared at the center of the counter electrode. The plasma was characterized by plasma emission spectroscopy. Silicon thin films were deposited on a glass substrate. It was found that increasing the magnetic flux density resulted in increasing plasma emission intensity, film deposition rate, and crystallinity. The maximum deposition rate of 6.9 nm/s was achieved with high crystallinity and photo-sensitivity at a plasma excitation frequency of 13.56 MHz, a substrate temperature of 300 °C and a magnetic flux density of 75 mT. Our results indicate that the magnetic field is effective in promoting fast chemical vapor deposition of microcrystalline silicon thin films with photo-sensitivity using the HEEPT technique. We consider that the effectiveness is due to a decrease of electron temperature caused by drift motion of electrons in the magnetic field inside the orifice. 相似文献
53.
Kawai T Chun WJ Asakura K Koike Y Nomura M Bando KK Ted Oyama S Sumiya H 《The Review of scientific instruments》2008,79(1):014101
The design and performance of a new high-pressure and high-temperature cell for measurement of x-ray absorption fine structure (XAFS) spectra of solid catalysts working in a flowing liquid are presented. The cell has flat, high-purity sintered cubic boron nitride (c-BN) windows which can tolerate high temperature (900 K) and high pressure (10 MPa). The c-BN is a new material which has the highest tensile strength, second only to diamond, and is also chemically and thermally stable. The use of the cell is demonstrated for measurements of PtPdAl(2)O(3) and Ni(2)PSiO(2) hydrodesulfurization catalysts at reaction conditions. A technique called delta chi (Deltachi), involving determining the difference between XAFS spectra of the sample at reaction conditions and the bare sample, is introduced. 相似文献
54.
We investigated the effects of Al concentration on the reciprocated motion of twin boundaries in pre-strained Mg-Al-Zn alloys through a combination of applied compression and tension,in-situ electron-backscattering diffraction observations,and high-angle annular dark-field scanning transmission electron microscopy observations.The twin growth was restricted by increased Al concentration,which resulted in the occurrence of smaller-sized twins.The reverse motion of twin boundaries was also restricted,resulting in the formation of higher fractions of secondary twins and 2-5° boundaries during reverse tension.The secondary twins and 2-5° boundaries mainly contributed to the increased ultimate tensile strength of the pre-strained Mg alloys.This effect is more significant in Mg alloys with larger pre-compression.Moreover,the increased amount of the Al solute atoms,rather than the precipitates,mainly contributed to the increased strengthening effect on the twin boundary motion.Our research contributes to development of high-strength Mg alloys by stabilizing twin boundaries. 相似文献
55.
Fujio Abe Toshio Ohba Hideko Miyazaki Yoshiaki Toda Masaaki Tabuchi 《Materials at High Temperatures》2019,36(4):368-378
The effect of W-Mo balance and boron nitrides (BN) on creep rupture ductility has been investigated for five heats of 9% Cr steel with 1.5% Mo equivalent, 0.003% boron and 0.05% nitrogen at 600oC, 650oC and 700oC. The maximum time to rupture was 68,718 h at 650oC. The reduction of area (RA) slightly decreases for up to about 8000 and 1000 h at 600 and 650oC, respectively, while it significantly decreases above those. The BN particles are responsible for the degradation in RA at low stresses and long times by accelerating the formation of creep voids. At high stresses and short times, the RA decreases with increasing time to rupture and with increasing W concentration and concomitantly with decreasing Mo concentration. The rupture ductility is evaluated by using a semi-logarithmic diagram of the RA and total elongation, showing the necking dominant and void swelling dominant regions. 相似文献
56.
57.
Takahiro Wada Yuichiro Manabe Issei Nakamura Yuichi Tsunoyama Hiroo Nakajima Masako Bando 《Journal of Nuclear Science and Technology》2016,53(11):1824-1830
We have investigated the dependence of the mutation frequency on the dose and dose rate of artificial radiation using the Whack-A-Mole (WAM) model that we recently proposed. In particular, we pay special attention to the case of long-term and low-dose-rate exposure. Our results indicate that the WAM model successfully describes the dose-rate dependence, and it can replace the so-called dose and dose-rate effectiveness factor (DDREF), which has been used for long, to account for the differences between high-dose-rate and low-dose-rate data. The basic properties of the WAM model are discussed with special emphasis on the dose-rate dependence in order to demonstrate how the dose-rate dependence, which is built into the model explicitly, plays a key role. Biological effects of long-term exposure to extremely low-dose-rate radiation are discussed in light of analysis of mega-mouse experiments using the WAM model. In the WAM model, the effects of long-term exposure show a saturation property, thus making it distinctly different from the ‘linear no threshold (LNT)’ hypothesis that predicts a linear increase of the effects with time. 相似文献
58.
N. N. Faleev A. Yu. Egorov A. E. Zhukov A. R. Kovsh S. S. Mikhrin V. M. Ustinov K. M. Pavlov V. I. Punegov M. Tabuchi Y. Takeda 《Semiconductors》1999,33(11):1229-1237
Multilayer InAs-GaAs structures with an array of vertically aligned InAs quantum dots in a GaAs matrix, grown by molecular-beam
epitaxy, were investigated by crystal truncation rods and high-resolution x-ray diffractometry methods. It was shown that
the formation of scattering objects such as vertically aligned quantum dots in the structures strongly influences the mechanism
of diffraction scattering of x-rays and changes the spatial distribution of the diffracted radiation. This is explained by
the appearance of additional long-range order in the lateral arrangement of the scattering objects in the periodic structures,
by the curving of the crystallographic planes in the periodic part of the structure, and by the quasiperiodicity of the deformation
profile due to the vertically coupled quantum dots. The observed spatial distribution of the diffracted intensity can be explained
qualitatively on the basis of a new model where the scattering layers with quantum dots consist of defect-free, coherently
coupled, InAs and GaAs clusters.
Fiz. Tekh. Poluprovodn. 33, 1359–1368 (November 1999) 相似文献
59.
Noor Azwani Mohd Rasidek Koji Iwamoto Norazah Abd Rahman Yuichiro Nagatsu Hideaki Tokuyama 《International Journal of Food Properties》2018,21(1):2087-2099
In the present study, peel pectin jellies (PPJ) were isolated from banana peel Musa acuminata Colla (AAA, cv ‘Berangan’) varieties using water bath extraction; five jellies were produced, namely, PPJ_68%, PPJ_70%, PPJ_71%, PPJ_72%, and PPJ_76%. The effect of sugar content on the rheology of the PPJ and commercial fruit jelly was conducted at 25°C within 0.05–100 s?1 shear rate. Flow behaviour was evaluated on the test dispersions while frequency sweeps (Ea) to obtain the viscoelastic (G’ and G”) were performed on the jellies. PPJ dispersion showed shear thinning flow behaviour, a good fit to the Casson model. Sugar concentration does not affect Casson parameters (Kc, Koc, ?ca, and σoc). Frequency sweep decreased as viscosity increased which revealed high dependence for both G’ and G”. Tan δ for PPJ was more than unity which showed that jelly has less elastic properties. PPJ with the lowest sugar concentration, PPJ_68%, conducted at a high shear rate showed it was compatible with validation of the Cox–Merz rule. 相似文献
60.
Jyomoto T Azuma M Islam NN Fujinami R Takao T Ogawa T Tabuchi M Igarashi K Kato J Ooshima H 《Journal of Bioscience and Bioengineering》2006,102(3):193-197
The enzyme that catalyzes N-acyl linkage between myristic acid and the NH(2)-terminal glycine residue of the octapeptide Gly-Asn-Ala-Ala-Ala-Ala-Arg-Arg-NH(2) in aqueous solution without ATP and coenzyme A was found in Pseudomonas aeruginosa. The enzyme was purified from cell-free crude extract using DEAE-Cellulose, Sephadex G-200, CM-Sephadex C-50, and hydroxyapatite column chromatographies, and then purified approximately 1900-fold with about 1.5% recovery of enzyme activity from the crude extract. Finally, the purified enzyme showed a main band on SDS polyacrylamide gel electrophoresis after staining with Coomassie Brilliant Blue. The band corresponded to a molecular mass of approximately 60 kDa. The K(m)s of the purified enzyme for the substrate myristic acid and the octapeptide were 0.36 and 2.6 mM, respectively. When myristoyl-CoA instead of myristic acid was used as the substrate for the enzyme reaction, myristoyl octapeptide could be synthesized as observed in the case of myristic acid. The K(m) of myristoyl-CoA was 0.17 mM. 相似文献