• 한국세라믹학회지
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• 제43권7호
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• pp.445-450
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• 2006

The preparation of AlN powder by SHS in the system of $Al-AlN-NH_4Cl$ was investigated in this study. In the preparation of AlN powder, the effect of gas pressure and the composition such as Al, AlF, and additive in mixture on the reactivity were investigated. At 60 atm of the initial inert gas pressure in reactor, the optimum composition for the preparation of pure AlN was 35 wt%Al+5 wt% $NH_4Cl+60wt%$AlN. The AlN powder synthesized in this condition was a single phase AlN with a whisker morphology.

• 한국가정과교육학회지
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• 제7권1호
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• pp.121-131
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• 1995

This article is the result of the investigation on the actual condition of food preparation program carried out in elementary schools. Food preparation program belongs to the subject of ‘Shilgwa(Practice)’at elementary level. Though the result shows that instructors have no big problem in teaching theoretical part of the program, it is seriously doubtful whether students can acquire any scientifically practical knowledge which is able to be got through ‘practice’Only 4% of the investigated schools have cooking rooms, and even they have only very few cooking utensils or instruments. In spite of the importance of children’s earlier initiation into food preparation program, most schools are very poorly facilitated for education the program.

• 한국세라믹학회지
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• 제32권1호
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• pp.57-62
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• 1995

The coating condition of reproducible anti-reflective coating film and the light transmittance characteristics of the prepared anti-reflective coating glass were investigated as a study for the preparation of single-layer anti-reflective coating glasss. In case of coating with the sol in which the solvent was substituted with the ethanol with the addition of 0.1 mol HNO3, the coated glass showed the minimum value of the refractive index of 1.464, light transmittance of 94.2% at 550nm standard wavelength which is 3.2% higher than that of the parent glass, and the reflectance in the entire wave range of visible light. The refractive index represented its minimum at the sol concentration of 1.0 mol per 100mols of water and the higher the sol concentration, the higher the refractive index, resulting in the decrease of the light transmitance. The production condition of the reproducible anti-reflective coating on glass with the maximum transmittance of 94.2% was 4cm/min of withdrawal speed, 40$0^{\circ}C$ and 1 hour of heat treatment temperature and time, resulting in the film thickness of 94nm.

• Journal of Welding and Joining
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• 제19권2호
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• pp.191-199
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• 2001

The oxidation and recrystallization behaviors of Ni-base single crystal superalloy, CMSX-2 were investigated to determine the condition of the preparation for transient liquid phase (TLP) bonding operations. The faying surfaces of CMSX-2 were worked by the shot peening, fine cutting and mechanical polishing treatments and the degree of working of treated surfaces was evaluated by the hardness test and X-ray diffraction method CMSX-2 was heat-treated at 1,173∼1.589k for 3.6ks in vacuum of 4mPa. The mechanically polished surface was slightly oxidized after heat treatment even in the vacuum atmosphere of 4mPa. The thickness of an oxide film increased with increasing the heating temperature and the surface roughness of the faying surface. Recrystallization occurred at the surface after heat treatment at above 1,423K when the hardness was increased more than Hv600 by the shot peening treatment while the mechanically polished or fine cut surfaces didn't recrystallized. Based on these results, it was clearfied that the mechanically polishing with fine abrasive grit could be used for the preparation of faying surface of CMSX-2 before bonding operation.

• 한국세라믹학회지
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• 제28권1호
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• pp.46-52
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• 1991

The hydroxyapatite powders were prepared by the reaction of Ca(CH3COO)2$.$H2O and H3PO4 in aqueous solution. Effect of Ca/P mole ration and pH value on the powder characteristics were investigated. For phosphoric acid was dissociated to PO43- ion above pH 10, the preparation condition of hydroxyapatite by H3PO4 solution had this value. Dried powders were agglomerated each other. The mean agglomerate particle diameter was minimum when the condition was pH 11, Ca/P=1.75 and its specific surface area was 97㎡/g. All powders had poor crystallinity and small CO2. It prevented CaCO3 from using aspirator in preparation and maturing time. In most cases, hydroxyapatite was decomposed into ${\beta}$-TCP at more than 800$^{\circ}C$, into ${\alpha}$-TCP at 1200$^{\circ}C$. However non-decomposed hydroxyapatite was remained in Ca/P=1.85.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제50권5호
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• pp.216-220
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• 2001

Piezoelectric ZnO thin films by Facing Targets Sputtering(FTS) method were deposited on slide glass. The Facing Targets Sputtering system can deposit thin film at plasma-free condition and change the deposition condition in wide range. The characteristics of ZnO thin films changed with power, working pressure and substrate temperature were investigated by XRD(x-ray diffractometer), alpha-step(Tencor) and SEM(Scanning Electron Microscopy) analyses. In the results, we suggest that FTS system is very suitable for the preparation of high quality ZnO thin films with good c-axis orientation.

• 한국잠사곤충학회지
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• 제55권2호
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• pp.44-53
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• 2019

Sericin has been removed in textile industry to improve the luster and hand of silk textile. Therefore, the sericin was considered as useless material. However, recently sericin has attracted researcher's attention since unique properties of sericin including high water retention, UV protection, and wound healing effect were reported. In spite of the useful properties of sericin as biomedical and cosmetic materials, its poor mechanical properties have restricted its industrial use in biomedical and cosmetic fields. To improve the mechanical properties, various sericins were prepared by different conditions, and the effects of the preparation condition on the structure and properties of sericin were examined. In this review paper, research trend in the structure and properties of sericin prepared with different conditions were intensively introduced.

• 한국콘텐츠학회논문지
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• 제12권6호
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• pp.249-264
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• 2012

본 연구는 성공적 노화에 대한 이론적 고찰을 통해 성공적 노화의 개념을 명확히 하고, 이를 위해서 어떻게 노후를 준비하여야 하는가를 밝히고자 하였다. 근로자의 노후준비에 영향을 미치는 요인들을 조사하고 그 요인들이 노후준비에 어떻게 영향을 미치는지를 확인하기 위해 경기도에 위치하는 반월공단과 시화공단에 근무하고 있는 40세 이상의 근로자를 대상으로 조사하였다. 조사기간은 2011년 10월 10일부터 10월 31일까지였으며, 수집된 자료는 총 280부였고, 이중 결측값이 있는 자료를 제외한 총 261부를 최종 분석 자료로 사용하였다. 자료의 분석은 SPSS 18.0 프로그램을 이용하여 빈도분석, 요인분석, 차이검정, 그리고 다중회귀분석 등을 실시하였다. 연구결과는 다음과 같다. 첫째, 인구사회학적 특성이 노후 준비도에 미치는 영향에 대한 분석결과 건강상태가 전반적인 노후준비에 정(+)의 영향을 미치고, 연령, 학력, 월 평균수입, 종교, 그리고 자녀수가 부분적으로 정(+)의 영향을 미치는 것으로 나타났다. 둘째, 업무특성이 노후준비에 미치는 영향관계에 관한 분석에서 직무만족은 신체적 노후준비와 경제적 노후준비에 정(+)의 영향을 미치고, 직업몰입은 경제적 노후준비에만 영향을 미치는 것으로 나타났다. 세째, 인구사회학적 특성에 따른 노후준비도의 차이분석에서 연령, 학력, 배우자 유무, 종교유무, 건강상태, 그리고 자녀수에서 차이가 나타났다.

• 한국전기화학회:학술대회논문집
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• 한국전기화학회 2005년도 수소연료전지공동심포지움 2005논문집
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• pp.369-372
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• 2005

• 가족자원경영과 정책
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• 제10권1호
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• pp.33-51
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• 2006

Today, the Korean society is experiencing an increase in serious problems, such as child abuse, unmarried mothers, single mothers, which cannot be overlooked as simply trivial family matters. The increase in these problems is caused by the rapid change that has taken place within our society, which has emasculated the power of our traditional values and behavior patterns to cope with contemporary life styles. Premarital Preparation Education is starting to gain attention as a preventive measure that can overcome this serious family crisis. Although the importance of the Premarital Preparation Education program cannot be overemphasized, there are only few cases where engaged couples and unmarried men and women are exposed to this type of program and actually experience its benefits. In other words, there is an urgent need to revitalize and increase the effects of the Premarital Preparation Education Program. This research was conducted in order to find a way to revitalize and to increase the effects of the program, so that more and more people can participate and receive benefits from it. First, we have analyzed the program's contents and the current condition on how the program is actually conducted. Then we have compared real case examples of the program and analyzed the current situation and its problems.