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排序方式: 共有1402条查询结果,搜索用时 15 毫秒
1.
The World robot summit disaster robotics category – achievements of the 2018 preliminary competition
Satoshi Tadokoro Tetsuya Kimura Masayuki Okugawa Katsuji Oogane Hiroki Igarashi Yoshikazu Ohtsubo 《Advanced Robotics》2019,33(17):854-875
The World Robot Summit is a robot Olympics and aims to be held in a different country every four years from 2020. The concept of the Plant Disaster Prevention challenge is daily inspections, checks, and emergency response in industrial plants, and in this competition, robots must carry out these types of missions in a mock-up plant. The concept of the Tunnel Disaster Response and Recovery challenge is emergency response to tunnel disasters, and is a simulation competition whereby teams compete to show their ability to deal with disasters, by collecting information and removing debris. The Standard Disaster Robotics challenge assesses, in the form of a contest, the standard performance levels of a robot that are necessary for disaster prevention and emergency response. The World Robot Summit Preliminary Competition was held at Tokyo Big Sight in October 2018, and 36 teams participated in the Disaster Robotics Category. UGVs and UAVs contended the merits of new technology for solving complex problems, using core technologies such as mobility, sensing, recognition, performing operations, human interface, autonomous intelligence etc., as well as system integration and implementation of strategies for completing missions, gaining high-level results. 相似文献
2.
Improved atrial function in bicaval versus standard orthotopic techniques in cardiac transplantation
A Beniaminovitz MT Savoia M Oz M Galantowicz MR Di Tullio S Homma D Mancini 《Canadian Metallurgical Quarterly》1997,80(12):1631-1635
Atrial geometry is preserved in the bicaval technique of cardiac transplantation. Using Doppler echocardiography, we investigated the impact of this technique on preservation of atrial function and found that echocardiographic indexes of atrial function are improved in bicaval cardiac transplants versus the standard orthotopic transplants. 相似文献
3.
A Gopal G Li Mandri DL King C Marboe S Homma 《Canadian Metallurgical Quarterly》1994,105(6):1885-1887
Cardiac papillary fibroelastomas are unusual, frond-like growths typically found on cardiac valves, diagnosed incidentally on autopsy or cardiac surgery, but rarely during life. We report a rare case of an aortic valve papillary fibroelastoma detected by transthoracic echocardiography and confirmed by histologic study. 相似文献
4.
Tetsuya Nanba Shouichi Masukawa Atsushi Ogata Junko Uchisawa Akira Obuchi 《Applied catalysis. B, Environmental》2005,61(3-4):288-296
The catalytic decomposition of acrylonitrile (AN) over Cu-ZSM-5 prepared with various Cu loadings was investigated. AN conversion, during which the nitrogen atoms in AN were mainly converted to N2, increased as Cu loading increased. N2 selectivities as high as 90–95% were attained. X-ray diffraction measurements (XRD) and temperature-programmed reduction by H2 (H2-TPR) showed the existence of bulk CuO in Cu-ZSM-5 with a Cu loading of 6.4 wt% and the existence of highly dispersed CuO in Cu-ZSM-5 with a Cu loading of 3.3 wt%. Electron spin resonance measurements revealed that Cu-ZSM-5 contains three forms of isolated Cu2+ ions (square-planar, square-pyramidal, and distorted square-pyramidal). The H2-TPR results suggested that in Cu-ZSM-5 with a Cu loading of 2.9 wt% and below, Cu+ existed even after oxidizing pretreatment. The activity of AN decomposition over Cu/SiO2 suggested that CuO could form N2, but, independent of the CuO dispersion, nitrogen oxides (NOx) were formed above 350 °C. Cu+ and the square-pyramidal and distorted square-pyramidal forms of Cu2+ showed low activity for AN decomposition. Temperature-programmed desorption of NH3 suggested that N2 formation from NH3 proceeded on Cu2+, resulting in the formation of Cu+. The Cu+ ions were oxidized to Cu2+ at around 300 °C. Thus, high N2 selectivity over Cu-ZSM-5 with a wide range of temperature was probably attained by the reaction over the square-planar Cu2+, which can be reversibly reduced and oxidized. 相似文献
5.
J.H. Kaneko T. Tanaka S. Kawamura Y. Oshiki K. Tsuji M. Katagiri K. Ochiai T. Nishitani F. Fujita A. Homma T. Sawamura T. Iida M. Furusaka 《Diamond and Related Materials》2005,14(11-12):2027
Radiation detector was made of a high-quality CVD polycrystalline diamond composed of frost column like structure diamond grains, and induced charge distribution spectra and drift velocities were measured by using alpha particles. As a result, the CVD polycrystalline achieved maximum induced charge of 83% of HP/HT type IIa diamond. Moreover, the CVD crystal had lower charge loss on electrons compared with the HP/HT type IIa diamond. Drift velocities of electrons and holes were ve = 7.7 × 104 and vh = 7.3 × 104cm/s at an electric field of 20 kV/cm, respectively. In addition, response function measurement for 14 MeV neutrons was carried out. 相似文献
6.
With the growing size and complexity of power systems, system analysis—such as transients calculation—takes much time. Hence, fast calculation methods are required. Although parallel processing is a hopeful method, there have been difficulties in the parallel solution of linear equations which appear in power-flow calculations by the Newton-Raphson method. This paper aims at the fast calculation of the power-flow problem by means of parallel processing. In order to improve the suitability to the parallel solution of the differential equation in transients calculation, we assume the use of a direct-mapping parallel processing machine to map directly the network of a power system onto a network of processors. Under this assumption, we propose a new parallel-processing-oriented method in which the linear equation is solved by linear iterations between nodes with Aitken acceleration. We simulate the method on three model power systems and compare this Parallel Iterative Method (PIN) with a Parallel Direct Method (PDM) which uses the banded matrix according to the number of operations required. As a result, we can expect that PIM may solve linear equations faster than PDM with m processors, although the PIM might be inferior to the PDM with m × m processors, where m denotes the half-band width of the banded matrix. 相似文献
7.
Tetsuya Suemitsu Yoshino K. Fukai Hiroki Sugiyama Kazuo Watanabe Haruki Yokoyama 《Microelectronics Reliability》2002,42(1):47-52
The reliability of InP-based HEMTs is studied, focussing on how it is affected by the doped layer material and gate recess structure. Bias-and-temperature stress tests reveal that fluorine-induced donor passivation in the recess region, formed adjacent to the gate electrode, causes the source resistance (Rs) to increase at large drain bias voltages. The increase in Rs can be prevented by using InP or InAlP as the carrier supply layer material instead of InAlAs. On the other hand, the increase in the drain resistance (Rd) does not depend on the material of the carrier supply layer, which suggests that a mechanism different from that in the case of Rs should be considered. It is also found that a deep gate recess suppresses the increase in Rd after long-term stressing. 相似文献
8.
Fukuhara Mikio Mitsuda Tetsuya Katsumura Yuji Fukawa Akira 《Journal of Materials Science》1985,20(2):710-717
The effect of oxygen and carbide addition on the sinterability of TiN
y
(0.42<y<1)-Ni alloys, in which part of the nitrogen is replaced by oxygen was investigated. It was found that sinterability increased as the oxygen and carbide content increased, but the strength of the resultant sintered alloys was significantly reduced due to the presence of Ni3Ti and Ti2O3 phases when the oxygen content exceeded 50 mol %. The sintered alloy with the highest hardness was found whenx=0.7,y=0.78 and the (V,Ta)C content was 18% by weight and this alloy was characterized by having a low density, good corrosion resistance and the colour of gold. 相似文献
9.
Tetsuya Murai Yoshiharu Sato Germano Resconi Michinori Nakata 《Electronic Notes in Theoretical Computer Science》2003,82(4):186
The concept of granular computing is applied to Aristotle's categorical syllogism. Such kind of reasoning is called granular reasoning in this paper. For the purpose, two operations called zooming in & out are introduced to reconstruct granules of possible worlds. 相似文献
10.
A skew of a paper transferred by rubber rollers in printers is simulated by FEM software. Effects of an imbalance of preload, an imbalance distribution of coefficient of friction and a front tension on the paper skew are investigated and how to determine the skew direction are shown. A simulation model is composed of a feed roller, a preload roller and a paper. The feed roller is rotated forcibly by a certain degree at every calculation step and a deformation, displacement and strain of the paper and rollers are calculated. A series of calculation results is shown as a motion simulation. The results show that the paper skews to the smaller preload side, to the smaller coefficient of friction side, or to the opposite side of the front tension. Further, effects of a skew prevention guide plate is simulated. 相似文献