• Proceedings of the Korean Vacuum Society Conference
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• 2007.02a
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• pp.179-179
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• 2007

• Korean Journal of Child Studies
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• v.8 no.1
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• pp.15-29
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• 1987

The purpose of the present research was to investigate (I) the acquisition of character constancy of self and others as a function of age; (2) the pattern of acquisition of character constancy, and (3) the relationships between character constancy and conservation of number and mass. The subjects of this study were 160 children, 20 boys and 20 girls at each grade level, kindergarter through grade 3. The Character Constancy Tasks devised bi Rotenberg (1982) and conservation task of number and mass were administered to each child. Chi square, Guttman Scale analysis and Pearson's Correlation were used for the statistical analysis of data. The findings showed that there was increase with age in character constancy of others and of sell in that there was increase with age in children's belief that the characteristics of another person are stable across time and consistent despite changes in a person's appearance. Character constancy of others and of self were acquired in the developmental stages of identity, stability, and consistency. Character constancy of others and self correlated with the conservation of number and mass.

• Proceedings of the KSME Conference
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• 2000.11b
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• pp.67-76
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• 2000

Cr-Mo low alloy steels have been used for a long time for pressure vessel due to its excellent corrosion resistance, high temperature strength and toughness. The paper reviewed the latest trends on material development and some problems on Cr-Mo low alloy steel for pressure vessel, such as elevated temperature strength, hardenability, synergetic effect between temper and hydrogen embrittlement, hydrogen attack and hydrogen induced disbonding of overlay weld-cladding.

• Korean Journal of Pharmacognosy
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• v.30 no.1
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• pp.48-53
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• 1999

Isolation and quantitative determination of costunolide from Saussurea lappa Clarke (Compositae) has been conducted by using HPLC method. Costunolide in an acetone extract from the crude drug was separated on a RP-18 column using a $MeOH-H_20$ mixture (65:35) as an eluent and the average content is about $1.32{\sim1.42%.$ The content of costunolide in dried extract was decreased by about 24% in seven days. However it showed a slight decrease in solution. It is highly recommended that quantitative determination of costunolide from Saussureae Radix should be conducted as early as possible after solvent extraction.

• Bulletin of the Korean Mathematical Society
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• v.54 no.3
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• pp.993-1002
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• 2017

Let ${\Omega}$ be a bounded, uniformly totally pseudoconvex domain in ${\mathbb{C}}^2$ with the smooth boundary b${\Omega}$. Assuming that ${\Omega}$ satisfies the negative ${\bar{\partial}}$ property. Let M be a positive, finite area divisor of ${\Omega}$. In this paper, we will prove that: if ${\Omega}$ admits a maximal type F and the ${\check{C}}eck$ cohomology class of the second order vanishes in ${\Omega}$, there is a bounded holomorphic function in ${\Omega}$ such that its zero set is M. The proof is based on the method given by Shaw [27].

• Proceedings of the KSME Conference
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• 2000.11a
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• pp.67-76
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• 2000

Cr-Mo low alloy steels have been used for a long time for pressure vessel due to its excellent corrosion resistance, high temperature strength and toughness. The paper reviewed the latest trends on material development and some problems on Cr-Mo low alloy steel for pressure vessel, such as elevated temperature strength, hardenability, synergetic effect between temper and hydrogen embrittlement, hydrogen attack and hydrogen induced disbonding of overlay weld-cladding.

• Proceedings of the Korean Information Science Society Conference
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• 2006.06a
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• pp.409-411
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• 2006

써픽스 배열은 사전적 순서로 정렬된 써픽스들의 인덱스를 저장한 인덱스 자료구조로서, 긴 텍스트에서 반복되는 패턴 검색 시 효율적으로 사용 될 수 있다. 하지만 O($n\;log{\Sigma}$) 비트의 텍스트보다 큰 O(n log n) 비트 공간을 차지하기 때문에 대용량의 텍스트에 대해서는 큰 공간을 필요로 하는 문제점이 있다. 이를 해결하기 위해 압축된 써픽스 배열이 제안되었지만, 구축 시 이미 만들어진 써픽스 배열을 이용하기 때문에 실제 사용 공간을 줄이지는 못했다. 최근 써픽스 배열 없이 텍스트에서 직접 압축된 써픽스 배열을 구축할 수 있는 두 가지 알고리즘이 개발되었다. 본 논문에서는 이 두 가지 알고리즘을 구현한 후, 구축 시간과 사용 공간 등의 실험을 통해 기존의 써픽스 배열들과의 성능을 비교하고 분석한다.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.979-981
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• 2006

Recently as the well-being diffuse and the living standard improves. People's demand for an environment lifestyle is gradually on the rise. The major source of the subway running train is rolling noise generated by the surface condition of wheel and rail. In this study, we research trends on the reduction noise level. Further-more, special traffic Ubiquitous helps to environment technical development.

• The Korean Journal of Health Service Management
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• v.8 no.1
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• pp.41-50
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• 2014

This study was a descriptive study to investigate factors affecting sleep time in the Korean elders. A secondary data analysis was conducted using the data of "The Fifth Korea National Health and Nutrition Examination Survey, 2011". The survey included 3,487 people aged over 65 years and 1,163 samples were used for this study. Data were analyzed with the ${\chi}^2$-test and logistic regression using the SPSS/WIN 18.0 program. Analysis showed that sleep time was related with the number of chronic disease and limit on the activities of daily living(ADL). These findings suggest that nursing researchers need to consider chronic disease, and ADL as important factors affecting sleep time of Korean elders. Therefore nursing intervention focusing on the issues in needed to develope.

• Bulletin of the Korean Chemical Society
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• v.31 no.6
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• pp.1515-1518
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• 2010

Regio- and diastereoselective 1,3-dipolar cycloaddition reactions of nitrones {(Z)-${\alpha}$-phenyl-N-methylnitrone (1a) and (Z)-${\alpha}$-propyl-N-butylnitrone (1b)} with electron-deficient perfluoro-2-methyl-2-pentene (2) lead to novel isoxazolidines {5-fluoro-5-pentafluoroethyl-4,4-bis-trifluoromethyl-2-methyl-3-phenyl-isoxazolidine (3a) and 2-butyl-5-fluoro-5-pentafluoroethyl-4,4-bis-trifluoromethyl-3-propyl-isoxazolidines (3b) respectively} as major constituents. These derivatives were characterized by IR, $^1H$ and $^{19}F$ NMR, GC-MS and NOE measurements, and the absolute structure of 3a was confirmed by X-ray crystallography.