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排序方式: 共有493条查询结果,搜索用时 15 毫秒
81.
Katsuya Ogura Yuma Yamada Shugo Kajita Hirozumi Yamaguchi Teruo Higashino Mineo Takai 《Computational Intelligence》2019,35(3):625-642
Several attempts have been made to grasp three‐dimensional (3D) ground shape from a 3D point cloud generated by aerial vehicles, which help fast situation recognition. However, identifying such objects on the ground from a 3D point cloud, which consists of 3D coordinates and color information, is not straightforward due to the gap between the low‐level point information (coordinates and colors) and high‐level context information (objects). In this paper, we propose a ground object recognition and segmentation method from a geo‐referenced point cloud. Basically, we rely on some existing tools to generate such a point cloud from aerial images, and our method tries to give semantics to each set of clustered points. In our method, firstly, such points that correspond to the ground surface are removed using the elevation data from the Geographical Survey Institute. Next, we apply an interpoint distance‐based clustering and color‐based clustering. Then, such clusters that share some regions are merged to correctly identify a cluster that corresponds to a single object. We have evaluated our method in several experiments in real fields. We have confirmed that our method can remove the ground surface within 20 cm error and can recognize most of the objects. 相似文献
82.
83.
Zhang Lan Lu Jian Nogami Hirofumi Okada Hironao Itoh Toshihiro Arai Shozo 《Microsystem Technologies》2018,24(1):457-463
Microsystem Technologies - During the growth of Japanese cows, the ruminal pH value is an important physiological parameter, which remarkably affects their nutritional status. To monitor the health... 相似文献
84.
K. Ogura 《Electrochimica acta》1980,25(3):335-339
Kinetic equations for the passivation of metals are developed under the activation and diffusion controlled conditions. In various activation conditions, four Tafel slopes have been derived theoretically. In The diffusion controlled reaction, the kinetics depended on the rate constants for the forward and backward directions in the passive film growth process. If the forward rate constant is much smaller than the backward rate constant, the log of current was linearly related to the log of(time)?1/2, and the current approached zero after a long anodizing time. However, in the reverse case, the log of current was proportional to the log of (time + constant)?1/2 in a short passivation time; however, current did not approach zero but a constant after a long anodizing time. 相似文献
85.
Zhang Z Nishimura H Namimoto T Fujioka S Arikawa Y Nishikino M Kawachi T Sagisaka A Hosoda H Orimo S Ogura K Pirozhkov A Yogo A Okano Y Kiriyama H Kondo K Ohshima S Azechi H 《The Review of scientific instruments》2012,83(5):053502
X-ray line spectra ranging from 17 to 77 keV were quantitatively measured with a Laue spectrometer, composed of a cylindrically curved crystal and a detector. Either a visible CCD detector coupled with a CsI phosphor screen or an imaging plate can be chosen, depending on the signal intensities and exposure times. The absolute sensitivity of the spectrometer system was calibrated using pre-characterized laser-produced x-ray sources and radioisotopes. The integrated reflectivity for the crystal is in good agreement with predictions by an open code for x-ray diffraction. The energy transfer efficiency from incident laser beams to hot electrons, as the energy transfer agency for specific x-ray line emissions, is derived as a consequence of this work. 相似文献
86.
Accumulation of nitrous oxide in aerobic groundwaters 总被引:1,自引:0,他引:1
N2O concentrations in the groundwaters collected in the Kanto District and Nagano Prefecture in Japan and five counties in New York State were determined. These N2O data were obtained from the water samples from wells, springs and seepages from soils in forests and cropping fields. The N2O concentrations in all samples greatly exceeded those of atmospheric equilibration. The average concentration of 690 nM N2O is one order of magnitude larger than that in deep ocean. All groundwaters of the present study were aerobic with a high level of NO3−, but with the absence of NO2− and NH4+, and with a very low level of dissolved organic carbon. These characteristics suggest that the nitrate respiration in the aquifers is of little significance for the production of N2O.
ΔN2O/NO3− molar ratios in the groundwaters were between 10−4 and 10−2 (Δ indicates the excess gas over that which would be in equilibrium). This supports the above view since the observed N2O yield agrees with that reported for the production during an ammonia oxidation. If nitrification was indeed a major mechanism for the production of groundwater N2O, subsequent release of N2O from the aquifers that are polluted with nitrogen may deserve more close attention as a potential source of atmospheric N2O via diffusion and discharge. 相似文献
87.
A Yamamoto E Shimizu E Takeuchi H Houchi H Doi H Bando T Ogura S Sone 《Canadian Metallurgical Quarterly》1999,56(2):129-133
To clarify the host immune response and explore a new serological marker of lung cancer, we examined serum c-Myc antigens and auto-antibodies against c-Myc in 68 lung cancer patients and 30 healthy volunteers using bacterially synthesized glutathione S-transferase c-Myc fusion proteins and immunoblotting. The detection rate of anti-c-Myc antibodies was 13.2% (9/68) in lung cancer patients and 3.3% (1/30) in healthy volunteers. These anti-c-Myc antibodies were directed toward exon 2 alone (4/68), exon 3 alone (1/68), and both exon 2 and exon 3 (4/68) of c-Myc. Circulating c-Myc antigen was not detected in any individuals with lung cancer and normal controls. Age, sex, performance status, histology, stage, smoking history, and prior treatment of the patients with and without anti-c-Myc antibodies were not significantly different. The low incidence of anti-c-Myc antibodies and c-Myc antigens in peripheral blood suggests that these examinations are not useful in the serological diagnosis of lung cancer. 相似文献
88.
Solute distributions in the vicinity of grain boundaries in Al–Zn–Mg(–Ag) alloys were studied using a three-dimensional atom probe, in order to elucidate the mechanism of formation of precipitate free zones (PFZs) and the fundamental role of Ag in controlling PFZ width. It is shown that nanoscale clusters are formed within the PFZ in Al–Zn–Mg, despite the solute concentration remaining at the levels in the as-quenched state. Such observations have not previously been possible, and show unambiguously that vacancy depletion is the dominant mechanism of formation of PFZs in this alloy. In the Ag-containing alloy, a narrower PFZ is observed, with a reduced solute level, showing that here the dominant mechanism of PFZ formation is solute depletion. The role of Ag in this change of mechanism appears to be due to its favorable interactions not only with Mg and Zn atoms but also with vacancies. 相似文献
89.
Hirobumi Shibata Taku Ogura Keishi Nishio Hideki Sakai Masahiko Abe Kazuaki Hashimoto Mutsuyoshi Matsumoto 《SILICON》2011,3(3):139-143
Large-pore mesoporous silica particles were synthesized through a solvent evaporation process using hydrophobic fumed silica
particles and tetraethyl orthosilicate (TEOS) as silica sources. The solvent evaporation of an ethanol solution of fumed silica
particles, TEOS, HCl and triblock copolymer (F127) resulted in mesoporous silica particles with pores with sizes of about
7 nm. In addition, the interplanar spacing of the mesoporous silica particles can be controlled by changing the solvent evaporation
temperatures. 相似文献
90.
Nobuaki Nishimura Ryuichi Ogura Satoshi Matsumoto Maya Mizuno Kaori Fukunaga 《Electrical Engineering in Japan》2013,183(1):9-15
The stock of aged power equipment is increasing and it is important to clarify the characteristics of deteriorated insulating oil. This paper describes a basic study of molecular behavior in the oxidation of insulating oil by terahertz spectroscopy. The oxidation of insulating oil was modeled by using various compositions of dodecane and 2‐octanol. The terahertz measurements indicated that signi?cant absorption related to hydroxyl groups (‐OH) occurred between 6 and 7 THz. The absorption band was also observed in accelerated aging alkylbenzene, which is used in power equipment as insulating oil and is sensitive to hydrogen bonds. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 183(1): 9–15, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22335 相似文献