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71.
Shoya Ueno Yuki Nakamura Ken-Ichi Sugioka Masaki Kubo Takao Tsukada Masahito Uchikoshi Hiroyuki Fukuyama 《International Journal of Thermophysics》2017,38(2):16
The normal spectral emissivity of molten Cu–Co alloy with different compositions was measured in the wavelength range of 780 nm to 920 nm and in the temperature range of 1430 K to 1770 K including the undercooled condition by an electromagnetic levitator superimposed with a static magnetic field. The emissivity was determined as the ratio of the radiance from a levitated molten Cu–Co droplet measured by a spectrometer to the radiance from a blackbody calculated by Planck’s law at a given temperature, where a static magnetic field of 2.5 T to 4.5 T was applied to the levitated droplet to suppress the surface oscillation and translational motion of the sample. We found little temperature dependence of the normal spectral emissivity of molten Cu–Co alloy. Concerning the composition dependence, the emissivity decreased markedly above 80 at%Cu and reached that of pure Cu, although its dependence was low between 20 at%Cu and 80 at%Cu. In addition, this composition dependence of the emissivity of molten Cu–Co alloy can be explained well by the Drude free-electron model. 相似文献
72.
Koichi Mitsukura Hiromu Sakamoto Haruka Kubo Toyokazu Yoshida Toru Nagasawa 《Journal of Bioscience and Bioengineering》2010,109(6):550-553
To efficiently produce 1,3-adamantanediol (1,3-ad(OH)2) from 1-adamantanol (1-adOH), our stocks of culture strains and soil microorganisms were surveyed for hydroxylation activity towards 1-adOH. Among them, the soil actinomycete SA8 showing the highest hydroxylation activity was identified as Streptomyces sp. based on 16S ribosomal DNA sequence analysis. The reaction products were purified by silica gel column chromatography, and from NMR and MS analyses, they were identified as 1,3-ad(OH)2 and 1,4-ad(OH)2. Streptomyces sp. SA8 produced 5.9 g l? 1 1,3-ad(OH)2from 6.2 g l? 1 1-adOH in culture broth after 120 h at 25 °C. Using resting cells, 2.3 g l? 1 1,3-ad(OH)2 was produced after 96 h of incubation at a 69% conversion rate. In both cases, 1,4-ad(OH)2 was formed as a byproduct at a rate of about 15%. Strain SA8 also hydroxylated 2-adamantanol and 2-methyl-2-adamantanol. 相似文献
73.
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75.
Tae-Gew Ham Yukio Nakata Rolando Orense Masayuki Hyodo 《Canadian Metallurgical Quarterly》2010,136(5):697-705
In order to investigate the influence of water on compression characteristics of decomposed granite soils, single-particle crushing and one-dimensional compression tests were carried out on three types of decomposed granite soils as well as on quartz-rich silica sand under both dry and wet conditions. Results showed that the initial crushing strength of a single particle was reduced and strength variability increased due to the weakening effects induced by the presence of water. Moreover, it was observed that the one-dimensional compression behavior of decomposed granite soil was related to the initial crushing strength. Finally, the magnitude of initial crushing strength was also affected by the degree of weathering of the soil. 相似文献
76.
Tanaka Y Taguchi S Yoshida S Hori S Takagaki Y 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2002,43(5):306-311
Little is known about the effects of residual veterinary drugs on the allergic reaction, except for the antigenicity of antibiotics and synthetic antimicrobials. Therefore, 59 kinds of veterinary drugs were investigated for their effects on the IgE receptor-mediated beta-hexosaminidase release from RBL-2H3 cells as an index of immediate allergic reaction. We found that the antibiotics chlorotetracycline, doxycycline, monensin, the synthetic antimicrobial pyrimethamine and the steroid hormone testosterone inhibited beta-hexosaminidase release. Most of the veterinary drugs showed no action, though the ionophores lasalocid, salinomycin and the steroid hormone hexestrol promoted beta-hexosaminidase release from injured cells. Based on the residual levels of these drugs and the frequencies of detection in actual food samples, it seems unlikely that these drugs have any immediate allergic effect in practice. 相似文献
77.
We propose sealing techniques for medical hollow fibers to protect the inner surface of fibers from debris or water that scatters from targets. First, hollow fibers are sealed with a film of polymer that is easily formed by use of a dipping technique. The transmission loss of 20-microm-thick sealing film was 0.2 dB for Er:YAG laser light, and the maximum energy that is available for the film was 180 mJ. Second, a sealed glass cap was applied to the output end of hollow fiber. The silica-glass cap with a wall thickness of 400 microm shows a transmission loss of 0.5 dB and was not damaged by radiation of 400-mJ energy pulses. 相似文献
78.
Discovering emerging topics from WWW has been attracting attention of business professionals, especially marketing researchers. For this purpose, WWW can be a valuable source of information because it reflects the dynamics of human society. In this paper we aim at revealing the structure of WWW by using KeyGraph, a visualization method of hidden structure behind data, for understanding emerging topics. 相似文献
79.
Chance discoveries for making decisions in complex real world 总被引:1,自引:0,他引:1
Yukio Ohsawa 《New Generation Computing》2002,20(2):143-163
Chance discovery is to become aware of a chance and to explain its significance, especially if the chance is rare and its
significance is unnoticed. This direction matches with various real requirements in human life. This paper presents the significance,
viewpoints, theories, methods, and future work of chance discovery. Three keys for the progress are extracted from fundamental
discussions on how to realize chance discovery: (1) communication, (2) imagination, and (3) data mining. As an approach to
chance discovery, visualized data mining methods are formalized as tools aiding chance discoveries on the basis of these keys.
Yukio Ohsawa, Ph.D.: He received Bechelor of Engineering (1990) from Faculty of Engineering, Master of Engineering (1992) and Ph.D. (1995) from
Graduate School of Engineering, respectively of The University of Tokyo. In the doctoral course he began artificial intelligence
research, especially of abductive inference. He was a research associate (1995–1999) in Osaka University on studies of text
mining and related issues, and moved to the current position, associate professor in the University of Tsukuba in 1999. From
2001, he is also a researcher of TRESTO (changed to PRESTO) in Japan Science and Technology Corporation. He received best
paper awards in two Annual Conferences of Japasese Society of AI (1994 and 1998), and a Journal Paper Award from JSAI in 1998.
His social activities are committees of conferences e.g., International Conference of Multi-Agent Systems (ICMAS) since 1998
and Discovery Science (DS) since 2001, program chair of MultiAgent and Cooporative Computations (MACC, in Japan) in 1999,
and committes of meetings including ones on Chance Discovery. 相似文献
80.
A scheme is presented for the speed control of rolling mill drives. The proposed speed controller is based on a two-degree-of-freedom (TDF) structure and uses an observer-based state feedback compensator for the major control loop. The control method yields a robust system with respect to system uncertainties and modeling errors and is very effective for vibration suppression. Experimental verification was carried out on a prototype rolling mill minimodel system. The experimental drive system has a three-mass-model structure (motor-gear-load) connected by low stiffness shafts. The mechanical resonances and the inertia ratios between the motor, gear, and load are comparable to those of an actual rolling mill system (resonant frequencies are at 17.4 Hz and 51.3 Hz). The proposed scheme was compared to the conventional PI controller and the performance of each scheme is presented. A high closed loop speed bandwidth was obtained with the proposed TDF speed controller 相似文献