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111.
Shino T. Yoshitomi S. Nii H. Kawanaka S. Inoh K. Yamada T. Fuse T. Katsumata Y. Yoshimi M. Watanabe S. Matsunaga J.-I. 《Electron Devices, IEEE Transactions on》2002,49(3):414-421
High-frequency characteristics of SOI lateral BJTs designed for 2-GHz radio frequency (RF) applications are measured and compared for various link-base length, emitter width, and collector structure. Based on experimental data and device simulation, degradation mechanism of cutoff frequency for shorter link-base is analyzed. By suppressing external base-induced effects, peak cutoff frequency is increased from 10 GHz to 15 GHz 相似文献
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Kazuhiro Kohara Yoshimi Fukuhara Yukihiro Nakamura 《Neural computing & applications》1996,4(3):143-148
This paper proposes a selective presentation learning technique for improving the learnability and predictability of large changes by back-propagation neural networks. Daily stock prices are predicted as a complicated real-world problem, taking non-numerical factors such as political and international events into account. Training data corresponding to large changes of prediction-target time series are presented more often, and network learning is stopped at the point that has the maximal profit. When this technique is applied to daily stock-price prediction, the prediction error on large-change data was reduced by 11%, and the network's ability to make profits through experimental stock-trading was improved by 67% to 81%, in comparison with results obtained using conventional learning techniques. 相似文献
116.
The analytical method of fluorescent whitening agents (FWAs) in river waters was examined. Two types of FWAs were identified qualitatively in river waters with the aid of the extraction method developed in the present work and thin layer chromatography. 相似文献
117.
Kenji Monden 《Journal of Electronic Materials》2007,36(12):1691-1696
The creep properties of tin-based, lead-free solders, Sn-3.0Ag-0.5Cu and Sn-7.5Zn-3.0Bi, were investigated for the temperature
range from 298 K to 398 K. The creep rupture time decreases with increasing initial stress and temperature. The Omega method
is applied to the analysis of the solder creep curves. The creep rate is expressed by the following formula: , where and Ω are experimentally determined. The parameter , the imaginary initial strain rate, increases with increasing initial stress and temperature. The parameter Ω is temperature dependent, but less dependent on the initial stress. The apparent activation energy for is 108 kJ/mol in Sn-3.0Ag-0.5Cu and 83 kJ/mol in Sn-7.5Zn-3.0Bi. These values are close to the activation energy for the
lattice diffusion of tin. The creep rupture time is calculated using the parameters and Ω. The calculated creep rupture time is in good agreement with the measured creep rupture time. 相似文献
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Electrostatic immobilization of cetylpyridinium chloride to poly(vinyl alcohol) hydrogels for the simple fabrication of wound dressings with the suppressed release of antibacterial agents 下载免费PDF全文
Shunji Yunoki Masushi Kohta Yoshimi Ohyabu Masayuki Sekiguchi Takabumi Kubo Tetsuji Iwasaki 《应用聚合物科学杂志》2014,131(13)
Polymeric systems for antibacterial wound dressings require chemical reactions or syntheses for attaching or incorporating antibacterial moieties into polymer backbones. However, these materials often fail to satisfy the basic requirements, such as easy and inexpensive synthesis. We speculated that a positively charged organic antibacterial agent would be attracted to the polar groups of poly(vinyl alcohol) (PVA) hydrogels and would show suppressed release. PVA hydrogels containing cetylpyridinium chloride (CPC) were prepared by γ irradiation. CPC was barely released from the hydrogels, probably because of electrostatic interactions, and was stable upon γ irradiation. The suppressed release of CPC conferred antibacterial activity against Escherichia coli to the surface of the hydrogels, whereas no inhibition zone was observed around the hydrogels. The CPC‐containing PVA hydrogels were easy to prepare and contained known and safe materials. The simplicity and safety of this procedure for achieving the suppressed release of antibacterial agents were advantages of these CPC‐containing PVA hydrogels. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40456. 相似文献
120.
Akihiko Yano Yoshimi Kagimoto Kunio Saki Yasuyuki Yoshida Tsuneto Hirozane Masahiko Mega 《摩擦学汇刊》2013,56(4):633-638
The surface-modified material can be produced by laser and electron beam surface alloying of a plasma-sprayed molybdenum layer on Cr-Mo steel. The boundary lubrication properties and the metal structure of the surface alloy have been investigated. The main points of this study are as follows. 1. The surface alloy is thick, about 5 mm, and of uniform composition. 2. The surface alloy shows good wear resistance and good seizure resistance, in the same level as electroplated chromium and plasma-sprayed molybdenum layers. 3. Good wear resistance is attributable to the metal structure which is composed of hard M6C phase and soft α?Fe phase. 相似文献