• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.1412-1417
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• 2011

Safety is soaring up as a core value in accordance with the recent improvement of operating speed & incidents. rolling stock is a kind of system which works together with several components. one component has an effect on the sub-system, which can cause to the train safety operation, therefore reliability management of the major components of rolling stock is a kind of solution to the safety operation of train, but realistically maintenance in korea performed based on period rather than TBO of major components, but Japan does new maintenance system based on the major components, which optimizes maintenance tasks. actually Japan can apply to new maintenance system because they are ready in planning step but in this study, making a reliability data of major components and review the adaptability of new maintenance system to the rolling stock operating in Ansan line.

• Journal of the Korean Wood Science and Technology
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• 제22권3호
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• pp.59-67
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• 1994

The essential oils of leaves and resins from P. densiflora and P. koraiensis were analyzed to identify their components. After each retention times of 45 known terpenoids were dertermined with a fixed analytical condition by GC the essential oil compounds of leaves and resins were identified by comparing their retention times with the retention times of known standards. To confirm these results the essential oil components of leaves from P. koraiensis were analized by 2 different GC/MS. According to these results, 36 terpenoids in essential oils of leaves from P. densiflora and P. koraiensis were identified and 15 terpenoids and 22 terpenoids were identified from P. koraiensis resin and P. densiflora resin, respectively. The major components which are more than 2% of total amaunt of volatile components were as follows: 1. The major terpenoids of leaves from red pine. ${\alpha}$-pinene, camphene, ${\beta}$-pinene, D-limonene, ${\beta}$-phellandrene, myrcene, terpinolene, ${\alpha}$-terpineol. 2. The major terpenoids of leaves from korean pine. ${\alpha}$-pinene, camphene, myrcene, D-limonene, 3-carene, terpinolene, bornyl acetate, ${\beta}$-caryophyllene, ${\alpha}$-terpineol, borneol, ${\delta}$-cardinene. 3. The major terpenoids of resin from red pine. ${\alpha}$-pinene, ${\beta}$-pinene, myrcene, ${\beta}$-phellandrene, linalool, linalyl acetate. 4. The major terpenoids of resin from korean pine. ${\alpha}$-pinene, ${\beta}$-pinene, D-limonene, ${\beta}$-caryophyllene, phytol.

• 한국가정과학회지
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• 제5권1호
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• pp.94-106
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• 2002

The present study investigated free sugar, organic acid, volatile components in fresh leaf and root of the coriander respectively, and in blanched leaf and root of the coriander, respectively. The research results are as follows : Glucose, fructose and sucrose were detected in leaf and root of the coriander. The content of total free sugar was 22.91mg% in leaf and 23.84mg% in root. By blanching, the contents of total free sugar decreased to 21.28mg% and 21.89mg% in leaf and root respectively. Malic acid, trataric acid were detected in leaf and root of the coriander. The content of total organic acid in leaf was higher than that in root of the coriander. By blanching, the content of total organic acid significantly decreased in leaf and slightly decreased in root. A total of 98 flavor components were detected in the leaf of coriander and total contents of those were 878.485mg/kg. The major components were (E)-2-Decen-1-ol, (E)-2-Decenal, and (E)-2-Tetradecenal. And a large amount of aldehydes and alcohols were shown in the leaf of coriander. By blanching, a total of 75 flavor components were detected in the leaf of coriander and total contents of those were 846.49mg/kg. The major components were (E)-2-decenal, (E)-2-Tetradecenal, decanal. The amounts of aldehydes were increased more. However, the amounts of alcohols were decreased more than those of the fresh leaf, respectively. A total of 77 flavor components were detected in the root of coriander and total contents of those were 455.064mg/kg. The major components were (E)-2-Tetradecenal, (E)-2-Decenal, and (E)-2-Dodecenal. By blanching, the kinds and the contents of the flavor components decreased and the major components is the same of the fresh root. And the contents of aldehydes and alcohols, acids decreased. However, the contents of esters and ketons increased.

• 한국약용작물학회지
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• 제11권4호
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• pp.274-278
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• 2003

The various plant organs of fennel (Foeniculum vulgare Mill.) were investigated to identify their volatile components using Dynamic Headspace (purge & trap). They showed slight differences concerning the volatile components both qualitatively and quantitatively. Results revealed that trans-anethole (12.65%) was the major compound in the leaf. The highest compound was ${\alpha}-pinene$ (28.78%), and trans-anethole (7.90%) was highly detected in the stem. The maximum values were 5.64, 4.59, 1.58, 1.51, and 1.04% for ${\alpha}-pinene,\;{\gamma}-terpinene,\;{\beta}-pinene$, 1,8-cineol and fenchone, respectively in the flower. However, very little trans-anethole was detected (0.27%) in the flower. From these results, it was suggested that the major components were different depending on the plant organs. However it was demonstrated that the related plant organs like flower-fruit and leaf-stem contained the similar components.

• 한국초등과학교육학회지:초등과학교육
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• 제18권2호
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• pp.1-19
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• 1999

Based on the analysis of commonalities and differences in the views of science achievement in major reform documents in the United States and Korea, an aggregated view of science achievement is presented in this paper Science achievement is conceived of in terms of science content and science process. The components of science content include: (a) concepts and theories I n physical, life, and earth and space science;(b) science, mathematics, and technology;(c) science in personal and social perspectives;(d)history and nature of science;and (e) unifying themes. The components of science process include: (a) scientific understanding;(b) scientific investigation;(c) scientific communication; and (d) scientific habits of mind. The components of science process.cut across and intersect with the components of science content. The components of science achievement overlap and are related to one another. Despite such an overlap, understanding the rot e that each component plays provides insight into its unique contributions as well as its interactions with other components. A definition of science achievement and identification of its components based on major reform documents provides a guideline for science assessment as well a s science teaching and learning.

• 대한안전경영과학회지
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• 제19권4호
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• pp.189-208
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• 2017

This study is for figuring out major components of construction quality infrastructure and suggesting improvement plan by benchmarking global best practice model and analyzing gap between the model and sample practice. Based on improvement plan, researcher could derive major characters and components of construction quality infrastructure, and also about the priority among core competency components of construction quality experts. The result showed that the 'human resource' was ranked the best priority followed by 'method' 'environment', 'equipment' among major characters and components of construction quality infrastructure. Also, for core competency components of construction quality experts, 'number of years in work places' was the best priority, and the 'professional knowledge on engineering' was another priority ranked. Far from general perception on competency components, 'academic education' ranked the last. It may allude that the current education system in this country is not effective in developing competency of quality engineers. In summary, this study shows professionalism of quality engineer is the most important thing in all the components.

• 한국지역사회생활과학회지
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• 제26권3호
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• pp.541-549
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• 2015

This study compares the major nutritional components of the leaf, flesh, and seed of dry loquat (Eriobotrya japonicaLindl.). Among proximate compositions, the crude fat, crude ash, and dietary fiber of the leaf exceeded those of the seed and flesh, whereas the carbohydrate content of the leaf was lower than that of the seed and flesh. The main component of free sugars in the leaf, flesh, and seed was fructose. Total amino acids of the leaf, flesh, and seed were 552.43, 63.00, and 260.29 mg%, respectively. Although the amino acid composition of the leaf, flesh, and seed varied, glutamic acid and ${\gamma}$-aminobutyric acid were the major amino acids in the leaf, flesh, and seed. Major fatty acids of total lipid were oleic acid and stearic acid in the leaf and seed, and the major acid was linoleic acid in the flesh. Major organic acids were oxalic acid in the leaf, maleic acid in the flesh, and citric acid in the seed. Vitamin C content was higher in the seed than in the leaf and flesh.

• 한국연초학회지
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• 제26권2호
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• pp.109-116
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• 2004

This study was conducted to investigate the composition of flavor components of Elsholtzia ciliata and Eisholtzia splendens in order to obtain basic informations for the application of tobacco and food industry. Flavor components extracted were divided into three fractions ; essential oil, absolute and oleoresin from E. ciliata and E. splendens. Essential oil was extracted by simultaneous steam distillation(SDE), absolute and oleoresin were extracted by $100\%$ n-hexane and $50\%$ ethanol, respectively. Yields of the essential oil, absolute and oleoresin fractions from E. ciliata were $0.34\%,\;11.34\%\;and\;15.24\%,$ and those from E. splendends were $0.28\%,\;12.45\%\;and\;9.95\%$, respectively. The major components of essential oil of E. ciliata were naginata ketone$(29.37\%)$, elsholtzia ketone$(14.37\%)$ and rosefuran$(11.76\%)$. The major components of essential oil of E. splendens were 2-cyclohexen-1-one$(26.81\%)$, elsholtzia ketone$(13.46\%)$ and naginata ketone$(5.26\%).$ The composition of flavor components showed a slight difference between essential oils of E. ciliata and E. splendens. The major components of absolute fraction from E. ciliata were linoleic acid$(12.07\%),$ palmitic acid$(10.46\%)$ and 2-cyclohexene-1-one$(5.39\%).$ And those from E. splendens were linoleic acid$(12.38\%),$ palmitic acid$(9.47\%)$ and naginata ketone$(8.86\%).$ Ethyl linoleolate was a major component in oleoresin of E. ciliata and E. splendens.

• 한국식품영양과학회지
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• 제28권2호
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• pp.326-332
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• 1999

In order to develope useful components and to apply in food additives, various components in the leaves of baechohyang were determined according to picking date. Moisture and ash were reached to 74~82%, 1.5~3.4%, respectively, and major sugars were fructose, glucose, sucrose, and maltose. Glutamic, aspartic acid, and leucine constituted the main component amino acids and their contents were relatively higher in the samples of summer and young leaves. Among free amino acids, histidine showed the highest components and methionine were the lowest. Potassium, calcium, and sodium were main mineral components. The content of ascorbic acid were 6.6~9.2mg% and seasonal variations were negligible. Muture leaves contained more polyphenols as much as 108~181mg% and the amount of bound fractions were much more. Periodic evaluation of phenolic compounds were made and major components of bound fractions were caffeic, syringic, and ferulic acid.

• 한국약용작물학회지
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• 제12권2호
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• pp.149-153
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• 2004

This study was carried out to compare the major volatile components in essential oil from different origin of Atractylodes spp. which is being traded as a crude herbal drug in Korean herbal markets. From the two Atractylodes of major volatile components were similarly detected such as the ${\beta}-selinene,\;{\beta}-sesquiphellandrene$, germacrene B, 2,7-dimethoxy-2-methylnaphthalene and 9-methoxy-2,3-dihydrofuro{3,2-q}coumarin. Among the volatile components, the major components were 2,7-dimethoxy-2-methylnaphthalene (40.98%), 9-methoxy-2,3-dihydrofuro {3,2-q} coumarin (15.74%), and ${\beta}-sesquiphellandrene$ (1.98%) in both Atractylodes. As a results, It was found that the two Atractylodes were the same species which was being traded in the Korean herbal markets as the A. japonica. not to different species of A. japonica and A. macrocephalla, respectively.