• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.04a
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• pp.46-47
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• 2006

고주파유도가열 연소합성법으로 60MPa의 기계적 압력과 고주파유도가열 장치의 총용량 (15KW)의 90%의 출력을 가해 75초의 짧은 시간에 97%이상의 상대밀도를 갖는 $TaSi_2-SiC$ 복합체를 제조하였으며, 제조된 시편의 미세조직 사진으로부터 선형분석법으로 측정한 $TaSi_2-SiC$ 의 평균 결정립크기는 각각 250nm 과 60nm 이었다. 또한 제조된 시편을 연마하여 비커스 경도계를 이용하여 기계적 특성평가를 한 결과 경도 와 파괴인성은 각각 $1366Kg/mm^2$ 와 $305MPam^{1/2}$ 이었다.

• Journal of Powder Materials
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• v.10 no.5
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• pp.337-343
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• 2003

Nanostructured Cu-$Al_2O_3$ composite powders were synthesized by thermochemical process. The synthesis procedures are 1) preparation of precursor powder by spray drying of solution made from water-soluble copper and aluminum nitrates, 2) air heat treatments to evaporate volatile components in the precursor powder and synthesis of nano-structured CuO + $Al_2O_3$, and 3) CuO reduction by hydrogen into pure Cu. The suggested procedures stimulated the formation of the gamma-$Al_2O_3$, and different alumina formation behaviors appeared with various heat treating temperatures. The mean particle size of the final Cu/$Al_2O_3$ composite powders produced was 20 nm, and the electrical conductivity and hardness in the hot-extruded bulk were competitive with Cu/$Al_2O_3$ composite by the conventional internal oxidation process.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.28 no.2
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• pp.71-77
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• 2020

The checklist currently used for aviation safety inspection performed by ASIs(Aviation Safety Inspectors) consists of inspection groups and multiple items, it does not have safety attribute and structured hierarchy system which required to efficiently process aviation safety analysis. On this study, categorized the domestic and foreign ASI checklist by safety attribute from ICAO recommended and presented composition of checklist for safety assurance by comparative analysis composition of domestic and foreign ASI checklist.

• Journal of Energy Engineering
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• v.20 no.3
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• pp.252-258
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• 2011

Nickel fiber mat was investigated as a potential structured catalyst for steam reforming of biogas in the temperature range of $600-700^{\circ}C$. The activity of as-received catalyst was very low owing to the smooth surface of fibers. Pretreatment of the catalyst by oxidation followed by reduction under methane partial oxidation condition significantly improved the catalytic activity, although degradation of the activity was found during the reaction due to oxidation and sintering. This deactivation was retarded by supplying additional hydrogen in the inlet gases or by coating $CeO_2$ over the catalyst surfaces.

• School Mathematics
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• v.3 no.2
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• pp.215-231
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• 2001

The purpose of the study was to investigate the effectiveness of the manipulatives in instruction of mathematics to those who have learning disabilities. Two middle school students who revealed very low achievements in the previous mathematics tests were involved in this study. Unit Cubes were used as the manipulatives, and the researchers utilized this manipulatives to teach the number bases. After a series of instructions utilizing the Unit Cubes, the subjects were interviewed with semi-structured form. In general, the effect of using the manipulatives were positive. Both subjects could understand much better with the Unit Cubes, and revealed affirmative results such as their positive attitudes toward mathematics.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.20 no.9
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• pp.24-31
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• 2006

This study developed a human robot mast arm, which has a structure similar to the human arm, with the objective of taking over human works. The robot arm was structured to reproduce human actions using three axes on each of the shoulder and the wrist based on mechanics, and the actuator of each axis adopted an ordinary DC motor. The servo system of the actuator is a one body type employing an amp for electric power, and it was designed to be small and lightweight for easy installation. We examined the posture control characteristics of the developed robot mast arm in order to test its interlocking, continuous motions and reliability.

• The Korean Journal of Health Service Management
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• v.7 no.3
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• pp.15-28
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• 2013

The purpose of this study is to identify if there is difference in the attitude toward the elderly and the elderly patients among nursing students and nurses. Data were collected between August 1 and November 30, 2012 by using a structured questionnaire and the participants of this study were 423 nursing students in 6 universities and 244 nurses in 5 hospitals. The nursing students and nurses had more negative attitudes toward elderly patients than the elderly. There was difference in attitudes toward elderly patients according to grade, whether to take gerontological nursing course, the level of interest in the Aged, and whether to have experience in living with the old in the past among nursing students. There was difference in attitudes toward elderly patients according to the quality of volunteer service experience among nurses. In order to identify the attitudes accurately in nursing studies or education related to the elderly, the process to classify and define the objects of attitudes in details should be administered first.

• Korean Journal of Human Ecology
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• v.11 no.4
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• pp.357-365
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• 2002

The purpose of this study was to examine the effects of the environmental factors and the family structure on the academic achievements of their children. Among various environmental factors, the family income, the affective relationship between mother and child, and the mother's educational involvement are considered. Total of 164 mothers with children attending elementary school completed the structured questionnaires. The degree of educational involvement of single mothers was lower than that of mothers of both parents families. In order to analyze factors that affect children's academic achievement, the path regression was performed. The family income and the mother-child affective relationship were found to have indirect effects on the academic achievements of elementary school students through maternal involvement in their children's education.

• Korean Journal of Human Ecology
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• v.11 no.4
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• pp.321-334
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• 2002

This study is a non-structured developmental art-therapy case study having done 134 times of total treatments for a 12 years old girl, having extremely poor verbal communication ability and sociality comparing to her ability in perception and motion. I presumed the cause of this gap between perceptibility and the communication ability was a problem related to self-consciousness. To cure the problem, I provided treatment programs designed to use material which can create a stable and reliable environment and can give body experiences such as painting and play-dough. As the treatment programs progressed, I found she had changed gradually to lead the game by herself and to express her favorite colors and shapes. Also she became to be able to express her experience as a simple word and to response short answers for questions.

• Korean Journal of Human Ecology
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• v.14 no.5
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• pp.785-794
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• 2005

This is an empirical research on the effect of the product placement advertisement on the consumption behavior of college students. A structured survey to 342 students in and near Seoul shows that life style of the students significantly matters to the effect. That is, beauty-oriented students are more sensitive to the PPL than other student groups (i.e., career-oriented, saving-oriented, leisure-oriented, or freedom-oriented students). On the other hand, the freedom-oriented students are not sensitive to the PPL at all. Some statistical methods including factor analysis and multiple regression analysis were employed in order to get those results.