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61.
For the next generation optical switching networks, the intelligent control plane is a key enabling technique. In this paper, we review our recent research activities related to Generalized Multi-Protocol Label Switching ( GMPLS ) and OpenFlow-based control planes for both Wavelength Switched Optical Networks (WSON) and Elastic Optical Networks (EON). 相似文献
62.
Toshio Shimoo Takehiro Morita Kiyohito Okamura 《Journal of the American Ceramic Society》2001,84(12):2975-2980
Polycarbosilane-derived low-oxygen SiC fibers, Hi-Nicalon, were heat-treated for 36 ks at temperatures from 1273 to 1773 K in CO2 gas. The oxidation of the fibers was investigated through the examination of mass change, crystal phase, resistivity, morphology, and tensile strength. The mass gain, growth of β-SiC crystallites, reduction of resistivity of the fiber core, and formation of protective SiO2 film were observed for the fibers after heat treatment in CO2 gas. SiO2 film crystallized into cristobalite above 1573 K. Despite the low oxygen potential of CO2 gas ( p O2 = 1.22 Pa at 1273 K − 1.78 × 102 Pa at 1773 K), Hi-Nicalon fibers were passively oxidized at a high rate. There was a large loss of tensile strength in the as-oxidized state at higher temperatures because of imperfections in the SiO2 film. On the other hand, the fiber cores showed better strength retention even after oxidation at 1773 K. 相似文献
63.
64.
Hiroya Maeda Takehiro Kashiyama Yoshihide Sekimoto Toshikazu Seto Hiroshi Omata 《Computer-Aided Civil and Infrastructure Engineering》2021,36(1):47-60
Machine learning can produce promising results when sufficient training data are available; however, infrastructure inspections typically do not provide sufficient training data for road damage. Given the differences in the environment, the type of road damage and the degree of its progress can vary from structure to structure. The use of generative models, such as a generative adversarial network (GAN) or a variational autoencoder, makes it possible to generate a pseudoimage that cannot be distinguished from a real one. Combining a progressive growing GAN along with Poisson blending artificially generates road damage images that can be used as new training data to improve the accuracy of road damage detection. The addition of a synthesized road damage image to the training data improves the F‐measure by 5% and 2% when the number of original images is small and relatively large, respectively. All of the results and the new Road Damage Dataset 2019 are publicly available ( https://github.com/sekilab/RoadDamageDetector ). 相似文献
65.
M Sagawa JE Jones M Ebina S Jensen RI Linnoila 《Canadian Metallurgical Quarterly》1997,17(2-3):181-195
In situ PCR is a new technique for the localization of low copy number sequences. We report here a method for the in situ visualization of a point mutation in K-ras codon 12 by indirect in situ PCR. Twenty-five primers were examined to select mutant-specific primers. Harvested cell lines were fixed and suspended in PCR mixture. Forty cycles of PCR in cell suspension was performed in a thermal cycler using a hot start method. Cells were cytocentrifuged onto slides, and post-fixation was performed. The specimens on the slides were then hybridized with a digoxigenin-labeled probe, followed by color reaction. Both Calu-1 (mutated: TGT) and NCI-H460 (wild type: GGT) cells had strong hybridization signals in the nuclei with general primers. But with mutant-specific primers, only Calu-1 cells had hybridization signals. No signal was observed without primers or Taq DNA polymerase. Southern blotting of the same preparation confirmed desired amplification. We also applied direct in situ PCR, but this method failed to detect the point mutation. We conclude that our indirect in situ PCR method shows the feasibility of in situ identification of single cells carrying point mutations. 相似文献
66.
Hisayoshi Mitamura Seiichiro Matsumoto Takashi Miyazaki Timothy J. White Kiyoshi Nukaga Yoshihiro Togashi Tamio Sagawa Shingo Tashiro Desmond M. Levins Akira Kikuchi 《Journal of the American Ceramic Society》1990,73(11):3433-3441
The polyphase titanate ceramic containing sodium-rich simulated high-level nuclear waste was doped with 0.69 wt% of 244 Cm to accelerate long-term self-irradiation due to α decays. α autoradiography showed that α emissions were almost uniformaly distributed throughout the curium-doped samples on a >20-μm scale although micropore surfaces and titanium oxide agglomerates were free of α-emitting nuclides. The phase assemblage of the curium-doped titanate ceramic included freudenbergite and loveringite in addition to the more abundant oxide phases: hollandite, perovskite, and zirconolite. Accumulation of α decays was accompanied by a gradual decrease in density. The increment of density was – 1% after an equivalent age of 5000 yr. Leach tests showed a slight trend toward higher total release of curium with equivalent age. The release of soluble nonradioactive elements (e.g., Na, Cs, Sr, and Ca) in the oldest specimens (equivalent age, 2000 yr) varied from specimen to specimen but, on average, were higher than specimens that had suffered a lower radiation dose. 相似文献
67.
Hirofumi Yokota Kouichiro Sagawa Chikahiko Eguchi Masahiro Takehara Keizo Ogino Toshiro Shibayama 《Journal of the American Oil Chemists' Society》1985,62(12):1716-1719
New amphoteric surfactants were prepared from Nε-acyllysine which was obtained by the thermal dehydration of a higher fatty acid salt of lysine and was not soluble in water.
Nα,Nα-dimethyl-Nε-acyllysine was prepared by the catalytic reductive condensation of Nε-acyllysine ester with formaldehyde in good yield. Nα,Nα,Nα-trimethyl-Nε-acyllysine was obtained from the reaction of Nα,Nα-dimethyl-Nε-acyllysine ester with methyl iodide. Confirmation of the structure of these derivatives was obtained by spectrometric and
spectroscopic analyses.
The solubility of Nε-acyllysine was improved significantly by the introduction of Nα-methyl groups. Physicochemical and surface active properties of the derivatives were investigated in terms of isoelectric
points, dissolution temperatures, surface tensions, critical micelle concentrations (cmc), foaming properties and wetting
powers. Nα,Nα,Nα-trimethyl-Nε-acyllysine had lower dissolution temperatures than Nα,Nα-dimethyl-Nε-acyllysine. The latter showed lower surface tensions than the former at cmc. Nα,Nα-dimethyl-Nε-lauroyllysine was best in wetting power and foaming property. 相似文献
68.
69.
Y Shinohara I Sagawa J Ichihara K Yamamoto K Terao H Terada 《Canadian Metallurgical Quarterly》1997,1319(2-3):319-330
We isolated highly intact and tightly coupled mitochondria from the rat ascites hepatoma cell line AH130 by disruption of the cell membrane by nitrogen cavitation. These isolated mitochondria were found to have essentially the same functional properties as rat liver mitochondria, but unlike the latter, hexokinase (HK) was bound to their membrane. Using the tumor mitochondrial preparation, we examined the source of ATP for phosphorylation of glucose by HK under conditions in which intra- and extramitochondrial ATP-generation systems operated separately or together. Results showed that the membrane-bound HK utilized ATP derived from the most efficiently operating ATP generation system, i.e., oxidative phosphorylation. However, when the rate of extramitochondrial ATP generation was much greater than that of oxidative phosphorylation, HK used ATP from the extramitochondrial ATP-generation system. 相似文献