• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2002.05a
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• pp.213-216
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• 2002

산소가 없는 상태에서 비교적 낮은 온도에서의 열, 충격 등에 의해 용이하게 발화, 연소하는 불안정한 물질에 의한 사고는 이전부터 많이 알려져 있다. 최근에는 fine chemical 분야의 발전에 따라 그 위험성이 인식되지 않은 채 제조되는 불안정한 물질이 늘고 있다［1-2］.(중략)

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.5
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• pp.2511-2515
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• 2013

Carbon black from pyrolysis of waste tires was used to modify and improve the fatigue properties and low temperature cracking of asphalt binder. 0%, 5%, 10%, 15% and 20% of pyrolyzed carbon black was mixed. Couple of laboratory tests, such as dynamic shear rheometer test and bending beam rheometer test, were carried out. The use of pyrolyzed carbon black decreased the fatigue at room temperature and improved the resistance of low temperature cracking up to $-12^{\circ}C$, but, was off the criteria at $-18^{\circ}C$.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2016.11a
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• pp.185-185
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• 2016

아크릴계 수지(resin)에 인조 흑연과 탄소나노튜브(carbon nanotube)를 1:1 비율로 혼합한 충전제(filler)와 용제(solvent) 및 기타 첨가제(additives)를 혼합하여 방열도료를 제조하여 수직방향 열전도도를 상온에서 평가하였다. 충전제의 함량을 1, 2, 5 중량 %로 변화시키며 원료들을 준비하여 교반기로 혼합한 뒤 3단 롤 밀(three roll mill)로 분산공정을 진행하여 3 종류의 도료를 제조하였다. 제조한 도료를 가로 11 mm, 세로 11 mm, 두께 0.4 mm의 Al 5052 알루미늄 기판에 스프레이 코팅 방식으로 도포한 후 $150^{\circ}C$에서 30분 동안 열경화 건조 과정을 거쳐 샘플을 제작하였다. 측정 시료의 형상은 대략적으로 Fig. 1과 같다. 열전도도는 식 $k={\alpha}{\cdot}C_p{\cdot}{\rho}$를 사용해서 계산된다. 여기서 k는 열전도도($W/m{\cdot}K$), ${\alpha}$는 열확산계수($mm^2/s$), $C_p$는 비열($J/kg{\cdot}K$), ${\rho}$는 밀도($g/cm^3$)를 나타낸다. 열확산계수는 독일 NETZSCH 사의 Laser Flash Analysis 장비(모델명 LFA 457)를 사용하여 측정하였는데, 기판 뒤쪽에서 레이저를 조사하고 도료층 전면에서 적외선 온도센서를 통해 시간에 따른 온도 상승곡선을 구한 후, 두 물체의 계면에서의 접촉 열저항(contact thermal resistance)을 감안하여 장비에 내장되어 있는 소프트웨어로 열확산계수가 계산된다. 비열은 같은 회사의 DSC(Differential Scanning Calorimetry) 200 F3 장비를 사용해 측정했으며, 밀도는 부피와 질량을 측정한 값을 이용하여 계산하였다. 도료를 도포하지 않은 bare Al plate에 대해서는 쉽게 열확산계수, 비열, 밀도를 측정하여 열전도도를 구할 수 있다. 도료가 코팅된 샘플에 대해서는 도료층을 일부 떼어내 비열을 측정하고, 밀도를 구한 후, 도료층의 열전도도가 2-layer 법으로 장비 내장 소프트웨어로 계산된다, 이때 Al 기판의 열확산계수, 비열, 밀도는 미리 측정한 bare Al plate의 값을 적용하였다. 실험 결과를 Table 1에 정리하였다. 흑연과 탄소나노튜브를 혼합한 충전제를 함유한 아크릴 복합체 박막에서 측정된 열전도도는 보통 고분자 재료의 열전도도 값의 상한 영역에 육박하는 값이며, 충전제 함량이 증가할수록 열전도도가 증가하는 경향을 보이고 있다.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.5 no.2
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• pp.58-66
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• 1991

This paper measured the characteristic of the thermal expansion, dielectric and conductivity to use $Sb_2O_3$ Filler in epoxy resin.The results are summarized as follow : 1 ) In the [$155^{\circ}C$] 1, The coefficient of thermal expansion increasing temperature obtained 8.19 in the case of pure epoxy resin and $4.5{\times}10^{-5}$ in the case of the mixing 7[%].2) The peak point of $\varepsilon\iota, \varepsilon\rho$ increasing $Sb_2O_3$ mixing ratio moved on the part of the high temperature. 3) The conductivity value increasing temperature shows the corner on the part of the Tg and it's Value became low the sample material with mixing I[%] than in case of pure epoxy resin.

• Journal of Energy Engineering
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• v.26 no.3
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• pp.71-77
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• 2017

In the event of loss of coolant accident (LOCA) and station black out (SBO) in the primary system of a nuclear reactor, the coolant water should be injected to reactor coolant system (RCS) without any intervention of operators or active components. To satisfy the requirements, hybrid safety injection tank (Hybrid SIT) was suggested by Korea Atomic Energy Research Institute (KAERI). The pressure equalizing time of Hybrid SIT is an important parameter to determine the timing of coolant injection. To predict the pressure equalizing time of the Hybrid SIT, a separate effect test facility was constructed and sensitivity tests were conducted in various conditions. The main parameter determining the pressure equalizing time was obtained from separate effect test (SET) results. The wall of condensation on the inner wall of SIT and direct contact condensation on the water surface affected to the pressure equalizing time very much. In this study, the effect of each condensation phenomena on pressure equalizing time was quantitatively analyzed from results of SET and a prediction method of pressure equalizing time was proposed.

• Resources Recycling
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• v.23 no.3
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• pp.13-20
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• 2014

Nowadays, due to the development of industrial and civil engineering technology, enlargement and diversification of concrete structures are being tried. At the same time, the hydration heat generated during the construction of large structures lead to thermal crack, which is occurs causing a problem that durability degradation. In this paper, in order to study the durability and reducing hydration heat of concrete according to the types of cement, that is ordinary portland cement, fly ash cement mixed with a two-component, ternary blend cement mixed with fly ash and blast furnace slag and low heat cement concrete are produced, and compare and analyze the results using property, durability and hydration characteristics, ternary blend cement is appeared to be the most excellent in durability and reduction of hydration heat, and it was determined suitable for construction of mass concrete and requiring durability.

• Journal of fish pathology
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• v.10 no.2
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• pp.97-111
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• 1997

In the winter of 1995, mass mortality occurred in cultured flounder, Paralichthys olivaceus in Gurongpo, Kyoungbuk, Korea. From the observations of moribund and dead fish, parasitic ciliates, which were shown as white spots to the naked eye, were considered to be involved in the mass mortality. From heavily infected flounders, histopathological, morphological and biological characterization of these ciliates were carried out. In the histological observation, many ciliates were found under the epithelia of gill filaments and skin, and caused hyperplasia of epithelial and mucus cells at the infected areas. The ciliates found on the body surface, fins and gills were very similar to Cryptocaryon irritans. However the ciliates showed two different patterns of reproductian, i.e., typical form(palintomy)and atypical form(budding plus multiple fission) at $16^{\circ}C$ of water temperature. The occurrence ratio between typical and atypical form was about 3:2. Tomitogenesis takes 8-14 days in the typical and 13-15 days in the atypical form. In the viability test at different temperatures and salinities, the typical form died below 30‰ at $12^{\circ}C$, below 20‰ at $16^{\circ}C$, below 15‰ at $20^{\circ}C$, and below 25‰ at $24^{\circ}C$, respectively. On the other hand, the atypical form died below 20‰ at $12^{\circ}C$, below 15‰ at 16-$20^{\circ}C$, and below 25‰ at $24^{\circ}C$, respectively. The results suggested that the atypical has better viability at low salinity than that of the typical at low temperatures. In the excystment time and success rates of excystment according to temperatures, the typical form showed 8 days, 30% at $12^{\circ}C$ : 6.5 days, 50%, at $16^{\circ}C$ : 5.5 days, 75% at $20^{\circ}C$ : and 7 days, 10% at $24^{\circ}C$, respectively. On the other hand, the atypical form showed 15.5 days at $12^{\circ}C$ : 14 days, 76.6% at $16^{\circ}C$ : 12 days, 72.2% at $20^{\circ}C$ : 10 days 31.6% at $24^{\circ}C$, respectively. The results suggested that the atypical form had longer excystment time than that of the typical form at any temperature and showed better stability at low temperatures.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1996.04a
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• pp.30-31
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• 1996

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2005.04a
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• pp.417-422
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• 2005

• Proceedings of the Korean Nutrition Society Conference
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• 2003.10a
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• pp.75-75
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• 2003