• Journal of the Korean Chemical Society
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• v.42 no.1
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• pp.78-83
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• 1998

It's necessary to develope a facile methodology forming ${\alpha}$-altropyranosidic linkage, for the synthesis of trisaccharide repeating unit of O-antigenic part of Campylobacter jejuni gram negative bacteria. In this paper, the effective synthesis of disaccharides containing ${\alpha}$-altropyranosidic linkage by 1,2-trans glycosidation of allal derivatives was discussed. 4, 6-O-Benzylidene-3-O-(t-butyldimethylsilyl)-D-allal was treated with DMDO (3,3-dimethy ldioxirane) to yield 1,2-anhydro-4, 6-O-benzylidene-3-O-(t-butyldimethylsilyl)-${\beta}$-D-altropyranose. The reaction of 1,2-anhydro-4, 6-O-benzylidene-3-O-(t-butyldimethylsilyl)-${\beta}$-D-altropyranose with allyl alcohol gave allyl 4, 6-O-benzylidene-3-(t-butyldimethylsilyl)-${\alpha}$-D-altropyranoside quantitatively, and reactions with glucals were also successful to prepare ${\alpha}$-altropyranosodic disaccharides. It is convinced that 1,2-trans glycosidation of allal derivatives should be an attractive choice for preparing oligosaccharides containing ${\alpha}$-altropyranosidic linkages.

• Journal of Advanced Navigation Technology
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• v.25 no.5
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• pp.336-343
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• 2021

Avionics corresponds to the brain, nerves and five senses of an aircraft, and consists of aircraft mounted electronic equipment of communication, identification, navigation, weapon, and display systems to perform flight and missions. It occupies about 50% of the aircraft system, and its importance is increasing as the technology based on the 4th industrial revolution is developed. As the development period of the aircraft is getting shorter, it is definitely necessary to develop a stable avionics SIL in a timely manner for the integration and verification of the avionics system. In this paper, we propose a method to replace the legacy SIL with the avionics simulation model framework based one and evaluate the framework based on the result of alternative application.

• JUMULGISUL / FOUNDRY TECHNOLOGY
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• v.3 no.1
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• pp.62-71
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• 1979

• The Science & Technology
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• no.10 s.425
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• pp.4-5
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• 2004

• Korea Petroleum Association Journal
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• no.4 s.146
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• pp.48-50
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• 1993

• Journal of Korean Electronics
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• v.4 no.6
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• pp.20-23
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• 1984

• JUMULGISUL / FOUNDRY TECHNOLOGY
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• v.4 no.2
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• pp.44-53
• /
• 1980

• Landscaping Tree
• /
• v.7 no.3_4
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• pp.33-37
• /
• 1992

• Korean Architects
• /
• no.4 s.360
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• pp.75-77
• /
• 1999

• Journal of The Korean Society of Grassland and Forage Science
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• v.10 no.3
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• pp.141-146
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• 1990

Changes in dry matter yield, crude components, nutrients uptake($P_2O_5$, $K_2O$, CaO, MgO) and sulphur containing amino acid(cysteine, methionine) of orchardgrass(Dacty1is glomerata. L) and alfalfa(A4edicago sativa. L) by gypsum application(as sulphur source, 0, 2. 5, 10, 20kg SIlOa) were investigated to understand the effect of sulphur on herbage production in pasture, which was established in 1987 as means of hand broadcasting. The effect of gypsum on dry matter yield at different cutting times during growing seasons has not been found both in orchardgrass and in alfalfa, but in respect to annual total dry matter yield there were increment in herbage yield (P<0.05) of alfalfa at 5, 10, 20kg SIlOa in 1989 and the amounts of sulphur taken up in herbage slightly increased according to the rates of gypsum application. Maximum apparent recovery of sulphur was 7.55% at 2kg SIlOa in orchardgrass and was 17.8% at 5kg S/lOa in alfalfa. There were no any great differences in the content of crude components of both species and this trend was similar with the mineral contents of orchardgrass. But in alfalfa, the amounts of $K_2O$, CaO, and $P_2O_5$ taken up were increased by gypsum application and the increment in the amounts of minerals taken up in herbage at 20kg SIlOa were 14.9 of $K_2O$, 9.1 of CaO, and 2.5kgIlOa of $P_2O_5$ as compared to those of at untreated plot. Cysteine and methionine were not influenced by gypsum applicaton not only in orchardgrass but also cysteine in alfalfa, however, the content of methionine in alfalfa was slightly increased at 2, 5, lOkg SIlOa and at 20kg SIlOa was reverse.