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111.
Yongbo Wu Jun Wang Yufeng Fan Masana Kato 《Journal of Materials Processing Technology》2005,170(3):563-569
In centerless grinding, it is difficult to optimize the grinding conditions for minimizing the workpiece roundness error because of the high number of process parameters such as center height angle, blade angle, and stock removal rate. We had previously proposed a function for evaluating grinding conditions, i.e., the waviness decrease rate, in order to automatically select the optimum process parameters. In order to build a closed-loop control system for the process parameters, however, it is necessary to find a practical way to determine the waviness decrease rate. In this paper, the relationship between the waviness decrease rate and the dynamic components of the grinding force was investigated analytically. It was found that the frequency characteristics of the waviness decrease rate show a similar tendency to those of the grinding force. A grinding force measurement system was built and experiments for measuring the frequency characteristics of the grinding force were carried out. As a result, it was confirmed that the waviness decrease rate can be determined by measuring the frequency characteristics of the grinding force. 相似文献
112.
Tomohiro Hashiguchi Yutaka Takita Kazuyuki Tajima Toru Katagiri 《Journal of Network and Systems Management》2016,24(3):557-577
Shared protection/restoration is a promising solution for reducing protection resources and is supported at each layer of the current multi-layer networks. Software-defined networking is expected to reduce equipment cost as well as operational cost by orchestrating these shared protection functionalities. However, although protection resource sharing improves link utilization, it sometimes increases the required equipment. Meanwhile, traffic re-aggregation at each layer is an important technique for low volume traffic to utilize the underlying link capacity more efficiently, but re-aggregation also makes it difficult to share protection resources with traffic at lower layers. In this paper, we present multi-layer network design strategy and method that reduce equipment cost by means of both traffic re-aggregation at each layer and protection resource sharing among multiple service traffic at different layers. The strategy first prioritizes traffic re-aggregation at each layer, and then maximally delegates shared protection to lower layers as long as it does not increase the required capacity at the lower layer. Evaluation results from the example three-layer networks confirm that the proposed method can effectively reduce equipment cost compared to the conventional design method. Cost reduction is achieved by leveraging shared protection functions at multiple layers. 相似文献
113.
Frank Bonnet Yuta Kato José Halloy Francesco Mondada 《Artificial Life and Robotics》2016,21(3):239-246
Robotic fish are nowadays developed for various types of research, such as bio-inspiredrobotics, biomimetics and animal behavior studies. In the context of our research on the social interactions of the zebrafish Danio Rerio, we developed a miniature robotic fish lure for direct underwater interaction with the living fish. This remotely controlled and waterproof device has a total length of 7.5 cm with the same size ratio as zebrafish and is able to beat its tail with different frequencies and amplitudes, while following the group of living animals using a mobile robot moving outside water that is coupled with the robotic lure using magnets. The robotic lure is also equipped with a rechargeable battery and can be used autonomously underwater for experiments of up to 1 h. We performed experiments with the robot moving inside an aquarium with living fish to analyze its impact on the zebrafish behavior. We found that the beating rate of the tail increased the attractiveness of the lure among the zebrafish shoal. We also demonstrated that the lure could influence a collective decision of the zebrafish shoal, the swimming direction, when moving with a constant linear speed inside a circular corridor. This new robotic fish design and the experimental results are promising for the field of fish–robot interaction. 相似文献
114.
An upflow anaerobic sludge bed (UASB)-submerged aerated biofilter (SAB) system that treats effluents from a jeans factory was evaluated. The 210-day operational period was divided into three phases (PI, PII and PIII), each with a different hydraulic retention time (HRT in h) and organic loading rate (OLR in kg COD/m3.d). In PI, the best performance was achieved using the UASB (HRT 24, OLR 1.3) with COD and color removal efficiencies of 59 and 64%, respectively; the corresponding values were 77 and 86% for the final effluent. In PII, the efficiencies were 50 and 55% using the UASB (HRT 16, OLR 1.2), respectively, and 69 and 81% for the final system effluent, respectively. In PIII, the UASB (HRT 12 and ORL 3.2) showed the poorest performance; the efficiencies decreased to 48 and 50%, respectively. The same phenomenon occurred in the system with corresponding efficiencies decreasing to 69 and 61%. Throughout the experiment, the system removal efficiencies were between 57 and 88% for nitrogen and between 14 and 63% for sulfate. The final effluent showed relatively non-toxicity or moderate toxicity using Daphnia magna as an indicator. Therefore, the overall results showed that the use of a sequential anaerobic-aerobic system is promising for treatment of textile industrial wastewater. 相似文献
115.
Hiroki Kikuchi Shigeki Hashimoto Shinichiro Tajiri Tsuneo Hayashi Yutaka Sugawara Michio Oka Yoshiyuki Akiyama Akira Nakamura Naoya Eguchi 《Journal of the Society for Information Display》2009,17(3):263-269
Abstract— A high‐pixel‐rate, high‐contrast (30,000:1) wide‐color‐gamut grating‐light‐valve laser projector is reported. A new optical engine enabling high‐frame‐rate (240 Hz) scan projection is employed. Panoramic wide‐angle‐scan projection with a 64:9 aspect ratio was also developed. Speckle noise is eliminated using a simple but highly efficient technique. The optical throughput efficiency of the grating‐light‐valve laser projector is reviewed. 相似文献
116.
Yasunobu Hitaka Yoshito Tanaka Yutaka Tanaka Ken Ichiryu 《Artificial Life and Robotics》2009,14(4):494-497
A tripod parallel mechanism consists of three links of fixed length and a rigid platform, and these are connected by revolute
joints. The platform can achieve sixdegrees-of-freedom (6-DOF) motion by the coordinated movement of the bottom ends of the
three links on a horizontal plane. This mechanism has advantages over the more common six extendible parallel manipulators.
It has a much larger work space and a simple structure. In this article, we show that the vector analysis for this tripod
parallel mechanism and the derivation of the positions of the three bottom ends of the links in an arbitrary attitude of platform
can be found by inverse kinematics and the conditions of geometrical constraint. Then, by a numerical simulation, the trajectories
of the bottom ends of the three links are shown. 相似文献
117.
Masatsune Kato Takaaki Aoki Takashi Noji Yasuhiro Ono Yoji Koike Tomoyuki Hikita Yoshitami Saito 《Journal of Superconductivity》1994,7(1):37-38
We have investigated the relation between the crystal structure and superconductivity in La1.9Bi0.1CuO4+
, in which the phase separation observed in La2CuO4+
is suppressed. A phase diagram in theT– plane is given for La1.9Bi0.1CuO4+
with excess oxygen. For very small values, the crystal structure is orthorhombic, and an orthorhombic-tetragonal phase transition occurs markedly at 0.03 in the measured temperature range between 13 and 293 K. Superconductivity is observed in the range of 0.04<<0.11. This is clear evidence thathigh-T
c
superconductivity also appears in the tetragonal phase. 相似文献
118.
K. Nishizawa H. Kato K. Mimori T. Yoshida N. Hasegawa M. Tsuji Y. Tamaura 《Journal of Materials Science》1994,29(3):768-772
Methanation reactivity was studied for the surface carbon deposited from CO2 on the surface of Rh-bearing activated magnetite. The most active material (Rh=0.83 wt %) for methanation was prepared by the impregnation method at 60°C and showed 98% conversion at 300°C. The surface carbon was composed of elemental carbon (-carbon) and polymerized carbon (-carbon), the proportion being dependent on the density of carbon deposited. In temperature-programmed surface reaction, the extent of conversion of the - and -carbon to CH4 was 0.34 (-carbon) and 0.53 (-carbon), respectively, and the total conversion was 0.87. This result indicates that not only elemental carbon but polymerized carbon (-carbon) could be converted to CH4 on the Rh-bearing activated (-carbon) magnetite, whereas -carbon is not hydrogenated on activated magnetite. 相似文献
119.
H. Kato T. Sano Y. Wada Y. Tamaura M. Tsuji T. Tsuji S. Miyazaki 《Journal of Materials Science》1995,30(24):6350-6354
The continuous methanation of CO2 has been accomplished over hydrogen-reduced Ni(II)-bearing ferrite (NixFe3–xO4–; x=0.39, > 0) in a mixed gas flow of CO2 and H2 at 250–375 °C. The yield and the selectivity for the methanation were larger than 50% and 95%, respectively, at the initial stage of the process. They decreased to 31% and 89%, respectively, after 6 h methanation. The innovative results can be ascribed to the use of the new material; hydrogen-reduced Ni(II)-bearing ferrite. Its formation was evinced by chemical analyses and the increase in the lattice constant; the lattice constant of the Ni(II)-bearing ferrite (a0 0.8375 nm) was enlarged to 0.8379 nm by hydrogen reduction. The enlarged lattice constant was not changed during the methanation. These findings suggest that the methanation occurs at the oxygen-deficient site of the hydrogen-reduced Ni(II)-bearing ferrite, as well as the formation of water by combination of the incorporated oxygens with hydrogen. The methanation consists of three steps of the elementary reaction. First, the oxygen-deficient sites are formed by hydrogen reduction; second, CO2 is reduced to elementary carbon and two oxygen ions which are incorporated into the oxygen-deficient sites; and third, the carbon deposited on the surface of the reduced ferrite is selectively hydrogenated to CH4. 相似文献
120.
Preparation of alumina and alumina-silica powders by wire explosion resulting from electric discharge 总被引:2,自引:0,他引:2
Wires of aluminium and aluminium-silicon alloys containing 5.2 and 12.1 wt% Si were exploded in air by electric discharge, and the properties of the powders obtained were examined. The powders consisted of large particles of several micrometres and very fine spherical ones, which were formed from the metallic droplets and vapours, respectively, and were mostly oxidized. The large particles decreased with an increase in the charged energy. Although the particle-size distribution was broad, the average particle sizes were small and were increased from 0.7 m to 1.3 m with an increase in the charged energy. These powders were identified as -alumina, amorphous alumina-silica compound and a small amount of the metal. The amorphous phase crystallized to mullite in the temperature range 1153–1243 K, and the crystallization temperature fell with increase in the charged energy because the amount of fine particles formed from the vapours increased. 相似文献