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Chung, Ha-Yull;Cho, Young-Jun;Kim, Tae-Wook
- Food Science and Biotechnology
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- v.14 no.2
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- pp.259-262
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- 2005
A fraction (CMEx-AH-${\beta}$) of water-soluble polysaccharides, showing selective antitumor activities, was isolated from the mycelia of solid cultured Agaricus blazei Murill by hot-water extraction, ethanol precipitation, and series of chromatography. Chemical characteristics of CMEx-AH-${\beta}$, were as follows: carbohydrate content, 48%; monosaccharide composition, Man:Glu:Gal (2:93:5); molecular weight, $2{\times}10^5$; uronic acid content, 6.2%. Fundamental structure of CMEx-AH-${\beta}$, was deduced as ${\beta}-(1\;{\rightarrow}\;6)$-D-glucan with ${\beta}-(1\;{\rightarrow}\;3)$-D-glucosidic side chains based on results of methylation and $^{13}C$ NMR spectroscopic analyses.
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Lee Seong-Won;Kim Seung-Hwan;Shin Seung-Kyo;Kim Tae-Wook
- Proceedings of the KSR Conference
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- 2005.05a
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- pp.550-555
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- 2005
In this research, safety requirements for guard rail, buffer stop, car stop scotch block, protection device, fire protection facilities, safety siding, escape facilities and inundation protection facilities are studied to establish a standard. First, various kinds of guard rails and their construction methods are investigated. Researches on the level difference of main track and guard rail, joint, length, and fastening force of guard rail are done. Second, the classification of buffer stop and car stop scotch block and its characteristics are examined, and the impact force, speed limit and capacity of buffer stop are summarized. Details of protection device, fire protection facilities, safety siding, escape facilities and inundation protection facilities are also investigated. From this fundamental research results, basic data on the safety facilities of railroad system are established.
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Kim, Tae-Wan;Park, Suhn;Park, Keun-Bae
- Nuclear Engineering and Technology
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- v.35 no.1
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- pp.1-13
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- 2003
In this study, an effective method to estimate the fundamental frequencies of co-axial cylinders immersed in fluid is proposed. The proposed method makes use of the equivalent mass or density that is derived from the added mass matrix caused by the fluid-structure interaction (FSI) phenomenon. The equivalent mass is defined from the added mass matrix based on a 2-D potential flow theory. The theory on two co-axial cylinders extended to the case of three cylinders. To prove the validity of the proposed method, the eigenvalue analyses upon coaxial cylinders coupled with fluid gaps are peformed using the equivalent mass. The analyses results upon various fluid gap is conditions reveal that the present method could provide accurate frequencies and be suitable for expecting the fundamental frequencies of fluid coupled cylinders in beam mode vibration.
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Breugel, K. van
- Proceedings of the Korea Concrete Institute Conference
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- 2006.11a
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- pp.1-12
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- 2006
For advanced civil engineering structures a service life of hundred up to hundred fifty and even two hundred years is sometimes required. The prediction of the performance of concrete structures over such a long period requires accurate and reliable predictive models. Most of the presently used, mostly experience based models don't have the quality and reliability that is required for reliable long-term predictions. The models designers are searching for should be based on an accurate description of the relevant degradation mechanisms. The starting point of such models is a realistic description of the microstructure of the concrete. In this presentation the need and the role of fundamental microstructural models for predicting the performance of concrete structures will be presented. An example will be given of a microstructural model with a proven potential for long-term predictions. Besides this also the role of models in general, i.e. in the whole design and execution process of concrete structures, will be dealt with. Finally recent trends in concrete research will be presented, like the research on self-healing cement-bases systems.
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