• Proceedings of the KIEE Conference
• /
• 1998.07e
• /
• pp.1746-1748
• /
• 1998

In this paper, the relation between the increment of metallic content such as copper(Cu) and iron(Fe) according to degradation of pole-transformer oil and change of electrical characteristics according to increment of metallic content was studied. As the result, electrical characteristics was decrease according to increment of metallic content, especially copper content, and the trend of T.C.G(Total Carbonic Gas) agreed with the trend of copper content.

• Bulletin of the Korean Chemical Society
• /
• v.29 no.3
• /
• pp.604-608
• /
• 2008

A series of N-alkenyl pyrrolidine-2-thiones were synthesized by the reaction between pyrrolidine-2-thione and various aldehydes such as n-propanal, isopropanal, n-butanal, n-hexanal, n-octanal and phenylacetaldehyde in 32-86% yields using microwave irradiation technique. Only one structural E isomers were predominantly formed within 15 minutes in chlorobenezene?/p-toluenesulfonic acid monohydrate.

• Korean Journal of Materials Research
• /
• v.5 no.5
• /
• pp.620-624
• /
• 1995

To study the acid and base properties of chemical-treated natural zeolite, FT-IR analysis was performed by the adsorption of pyridne and pyrrole and thermo-gravimetric analysis was done by the adsorption of NH$_{3}$. These solid catalysts have two acid sites, which are related to the Bronsted and Lewis acid sites, respectively. HIC-treatment led to the increased acidity and the maintained basicity.Acidity of NaHO-treatment samples also increased with thr NaOH-treatment but basicity decreased. The p-xylene selectivity on the chemical-treatment zelite was higher than that on the untreated zeolite.

• The Korean Journal of Mycology
• /
• v.6 no.1
• /
• pp.5-8
• /
• 1978

Attempts were made to investigate on the fatty acids of Agaricus bisporus, a cultivated edible mushroom. Fats were extracted from it and saponified with alcoholic potassium hydroxide. Isolated fatty acids were methylated and were subjected to column chromatography and G.L.C. Eleven saturated fatty acids, i.e., dodecanoic, tridecanoic, tetradecanoic, pentadecanoic, hexadecanoic, heptadecanoic, octadecanoic, eicosenoic, uncosenoic, docosenoic, and tricosenoic acids, were identified. Especially palmitic and stearic acids were abundant. Nine unsaturated fatty acids appear to exist in the carpophore.

• Proceedings of the Korea Society for Industrial Systems Conference
• /
• 2006.05a
• /
• pp.165-171
• /
• 2006

이제 e-러닝은 전 세계적으로 21세기형 교육 패러다임으로 부상하였고 단순히 정보통신매체 기반의 학습개념을 넘어서 국가 인적자원 개발을 통한 경쟁력 강화의 핵심 동력이 되었다. 하지만 이러한 국가 차원의 지원과 급속한 확산 속도에 비해서 실제적으로 e-러닝을 이용하고 있는 이용자들에 대한 구체적인 이용현황 조사는 미미한 실정이다. 이에 본 연구에서는 e-러닝 경험이 있는 대학생들을 중심으로 이용현황을 직접 조사하여, 그 결과 나타난 여러 가지 문제점과 현실적인 대안을 제시하고 실제적인 e-러닝 활성화에 기여하고자 한다.

• Journal of Ginseng Research
• /
• v.24 no.2
• /
• pp.83-88
• /
• 2000

The seasonal variation in the activity of sucrose synthase, ADP-glucose pyrophosphorylase and UDP-glucose pyrophosphorylase in roots of Panax ginseng C.A.Meyer have been studied. It was revealed that sucrose synthase and ADP-glucose pyrophosphorylase are adaptive enzymes and can serve as markers of sink strength, while UDP-glucose pyrophosphorylase is the maintenance enzyme. The average day temperature exceeded 24。C appeared to cause the disturbance in refilling process, affecting the starch synthesis. Study on the dependence of oxygen consumption in stele tissue with temperature revealed the sharp accelerating of this process after 24。C.

• Proceedings of The KACE
• /
• 2018.08a
• /
• pp.35-37
• /
• 2018

4차 산업혁명의 발달로 미래사회를 살아가는데 필요한 역량을 갖춘 인재를 키우기 위해 각 나라에서는 SW교육을 강조하고 있다. 본 연구는 한국의 정보교육에 대한 수요를 알아보고자 K대학교 대학생 131명을 대상으로 설문을 진행하였다. 설문 내용은 정보기술에 따른 사회변화, 중등교육과정에서의 정보교육 필요에 대하여 설문을 진행하였으며, 설문결과 모든 문항에서 재학생이 신입생에 비하여 정보교육에 대한 인식이 긍정적임을 알 수 있었다. 따라서 본 연구는 대학교 신입생과 재학생의 정보교육에 대한 인식을 분석하여 정보교육에 대한 필요성과 학생들의 정보교육에 대한 수요를 제시하는데 목적이 있다.

• Journal of Families and Better Life
• /
• v.14 no.2
• /
• pp.241-252
• /
• 1996

This study was designed to analysis a causal modeling between peer acceptance of children and the related variables. The subjects were 430 5th and 6th elemantary school children. Using questionnares data on peer acceptance aggression & withdrawal behavior rated by same-sex peers and mother-child attachment were gathered,. For the statiscal analyses multiple regression and path-analysis were used. The results show social behavior that effects peer acceptance is influenced by not only aggresive behavior but also withdrawal behavior, Peer acceptance was not affected directly by mother-child attachment and paternal education while academic achievement affected peer acceptance indirectly. Therefore children's peer acceptance is mainly determined by social behavior as well as academic achievement.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 1999.05a
• /
• pp.548-551
• /
• 1999

The cure characteristics of metal particle filled DGEBA/MDA/SN/ zeolite epoxy resin composite system for EMI shielding were investigated by dynamic DSC run method and FT-lR spectroscopy. As the heating rate increased, the peak temperature on dynamic DSC curve increased because of the rapid cure reaction. From the straight line of the Kissinger plot, the curing reaction activation energy and pre-exponential factor could be obtained. As the post-curing time at 15$0^{\circ}C$ increased, the glass increased the glass transition temperature or the thermal stability increased. When the post curing time is too long, the system filled with metallic Al particle can be thermally oxidized by the catalytic reaction of metal filler and the thermal stability of the composite for the EMI shielding application may be decreased.

• Bulletin of the Korean Chemical Society
• /
• v.33 no.7
• /
• pp.2411-2414
• /
• 2012