• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 한국식품저장유통학회 2002년도 춘계총회 및 제20차 학술발표회
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• pp.112.2-113
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• 2002

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 한국화재소방학회 2004년도 추계학술논문발표회 논문집
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• pp.82-87
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• 2004

• Proceedings of the KWS Conference
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• 대한용접접합학회 1990년도 특별강연 및 추계학술발표 개요집
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• pp.34-35
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• 1990

• Journal of Energy Engineering
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• 제25권3호
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• pp.34-40
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• 2016

For the safe handling of isoamyl alcohol being used in various ways in the chemical industry, the flash point and the autoignition temperature(AIT) of isoamyl alcohol was experimented. And, the lower explosion limit of isoamyl alcohol was calculated by using the lower flash point obtained in the experiment. The flash points of isoamyl alcohol by using the Setaflash and Pensky-Martens closed-cup testers measured $31^{\circ}C$ and $33^{\circ}C$, respectively. The flash points of isoamyl alcohol by using the Tag and Cleveland open cup testers are measured $43^{\circ}C$and $45^{\circ}C$. The AIT of isoamyl alcohol by ASTM 659E tester was measured as $419^{\circ}C$. The lower explosion limit by the measured flash point $31^{\circ}C$ was calculated as 0.87 vol%. It was possible to predict lower explosion limit by using the experimental flash point or flash point in the literature.

• Proceedings of the Korean Vacuum Society Conference
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• 한국진공학회 2000년도 제18회 학술발표회 논문개요집
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• pp.72-72
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• 2000

ITO(Indium-Tin-Oxide)는 n-type 전도 특성을 갖는 산화물 반도체로서 가시광 영역에서의 높은 광투과율 및 낮은 전기 비저항을 나타내기 때문에 태양전지, 액정디스플레이(liquid crystal display), 터치스크린(touch screen) 등의 투명전극 재료, 전계 발광(electroluminescent) 소자, 표면발열체, 열반사 재료 등 다양한 분야에 응용되고 있다. 본 연구에서는 타겟 제작에 드는 비용을 줄이고, 타겟 이용의 효율성을 높이기 위해 기존의 세라믹 타겟 대신 분말 타겟을 사용하여 유리 기판 상에 ITO 박막을 DC magnetron sputtering법에 의해 제조하고, 열처리 온도 및 열처리 분위기에 따른 ITO 박막의 전기적 광학적 특성을 조사하였다. 열처리 온도가 10$0^{\circ}C$이하인 경우 열처리하지 않은 시편과 동일하게 In2O3의 (411)면에 해당하는 peak가 관찰되었다. 그러나 20$0^{\circ}C$의 온도로 열처리 할 경우 (411)면 peak의 세기는 상대적으로 감소하고 대신 이전에 나타나지 않았던 (222)면에 대응하는 peak 세기가 현저하게 증가함을 알 수 잇다. 이것은 ITO 박막의 경정성장이 열처리 전 (411)면 방향으로 이루어지나 20$0^{\circ}C$의 온도로 열처리 후 재결정화에 의해 (222)면 방향으로의 우선방위를 갖고 성장함을 의미한다. 또한 주로 높은 기판온도에서 관찰되었던 (211), (400), (411), (440), (622)면 등에 해당하는 peak가 나타남을 볼 수 있었다. 열처리 온도를 더욱 증가시킴에 따라 결정구조에는 큰 변화 없이 (222)면 peak 세기가 증가하였다. 한편 열처리 온도를 더욱 증가시킴에 따라 (222)면 peak 세기가 상대적으로 조금 감소할뿐 XRD회절 결과에는 큰 변화를 관찰할 수 없었다. 이러한 결과로부터 기판을 가열하지 않고 증착한 ITO 박막의 재결정화에 필요한 최소의 열처리 온도는 20$0^{\circ}C$이며, 그 이상의 열처리 온도는 ITO박막의 결정구조에 큰 영향을 미치지 않음을 알 수 있었다. 열처리 전 비저항은 1.1$\times$10-1 $\Omega$-cm 의 값을 가지거나 10$0^{\circ}C$의 온도로 열처리함에 따라 9.8$\times$102$\Omega$-cm 로 약간 감소하였다. 열처리 온도를 20$0^{\circ}C$로 높임에 따라 비저항은 급격히 감소하여 1.7$\times$10-3$\Omega$-cm의 최소값을 나타내었다. 열처리 온도가 10$0^{\circ}C$인 경우 가시광 영역에서의 광투과율은 열처리하지 않은 시편과 비교해 볼 때 약간 증가하였다. 열처리 온도는 20$0^{\circ}C$로 증가시킴에 따라 투과율은 크게 향상되어 흡수단 이상의 파장영역에서 90% 이상의 투과율을 나타내었다. 이러한 광투과율의 향상은 앞서 증착된 ITO 박막이 열처리 중 재결합에 의해 우선 성장 방위가 (411)면 방향에서 (222)면 방향으로 변화되었기 때문으로 생각된다. 그러나 열처리 온도를 20$0^{\circ}C$이상으로 증가시켜도 광투과율은 큰 변화를 나타내지 않았다.

• Explosives and Blasting
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• 제22권3호
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• pp.79-84
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• 2004

It is well accepted that modem emulsion explosives are intrinsically much less sensitive than traditional products such as dynamites or black powder. However, they have still been involved in a significant number of accidental explosions. In October 1975, Canadian Research, Limited's, Energetic Research Laboratory in Quebec exploded. Although explanations for the incident varied, one logical explanation was that the pump used in transporting the emulsion dead headed, thereby turning mechanical work in to frictional heating under a zero flow rate. There is a minimum pressure required for combustion(MBP) to propagate in emulsion explosives. A stable deflagration may lead to a deflagration-to-detonation transition(DDT) in emulsion explosives. Tests were also performed on sensitized sampled consisting of 6 to 21% waters as well as 1 to 11% aluminium powder. It was founded the emulsion explosives consisting of 6% waters had the lowest minimum homing pressure(MBP) of 3 bar, and the 21% waters were unable to achieve sustained homing at pressures as high as 100 bar. The aluminium contained explosives tested here displayed a MBP higher than that of without emulsion. It appears that this test may offer a firm ground for the classification of emulsion explosives in view of the regulating the hazards associated with the various process used for their manufacturing and transport.

• Journal of Food Hygiene and Safety
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• 제26권4호
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• pp.308-314
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• 2011

This study surveyed and compared the temperatures established in display stands and food surfaces for cold and frozen foods in large discount stores in Korea. The temperatures established in display stands for cold food ranged with $3.5{\pm}1.8^{\circ}C$ as mean, minimum and maximum were $0^{\circ}C$ and $7^{\circ}C$. However, the surface temperatures of cold food on sale ranged with $10.7{\pm}2.9^{\circ}C$ as a mean, minimum $4.6^{\circ}C$ and maximum $18.4^{\circ}C$. Totally, the surface temperature of cold food on sale was $7.2^{\circ}C$, as a mean, higher than established in display stands for cold food in large discount stores in Korea. 53% of the surveyed cold foods were more than $10^{\circ}C$ in surface temperature and only 47% was less than $10^{\circ}C$. The differences between temperatures were lowest in fruits, salads and vegetables, but highest in milk products. On the other hand, the temperatures established in display stands for frozen food showed a range with $-20.7{\pm}1^{\circ}C$ as a mean. However, the surface temperatures of frozen food on sale showed a range with $-15.4{\pm}5^{\circ}C$ as a mean, minimum $-28^{\circ}C$ and maximum $-4.6^{\circ}C$ (included defrosting). The surface temperatures of frozen food, frozen meats, frozen processed foods and ice creams were $-13.8^{\circ}C$, $-15.9^{\circ}C$, and $-16.8^{\circ}C$, respectively. Only 32.3% of surveyed frozen foods showed less than $-18^{\circ}C$ in surface temperature. In conclusion, the temperatures established on cold and frozen food display stands were less than those of cold and frozen food surfaces on sale. There was also much variation in food surface temperatures during cold and frozen food storage and sales. Therefore, a temperature management system technology use at the distribution level for cold and frozen foods will be developed.

• Journal of Animal Environmental Science
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• 제11권2호
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• pp.103-110
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• 2005

The study was carried out to develop the real time measuring technique of ammonia and carbon dioxide concentration emitted from growing-finishing pig house in winter and estimate ammonia emission rate emitted from the pig house. As the study was carried out, environmental management technique for the pig house and odor abatement skill could be properly developed to reduce the residence's annoyance. The room temperature of the growing-finishing pig house was $10^{\circ}C$ higher than outdoor air temperature in spite of additional heating, because of heat emitted from body temperature of the pigs. The daily variation pattern of room temperature in the pig house shows the similar tendency with outdoor air temperature. The daily mean ventilation rate per head was $16\;m^3/h$ and ranged from $12\;m^3/h$ to $22.4\;m^3/h$. The difference of day and night for ventilation rate was about 2 times. The ammonia emission rate was $208{\pm}28\;mg/h{\cdot}pig$ per daily basics calculated with ventilation rate and ammonia concentration.

• Journal of the Korean Institute of Gas
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• 제20권2호
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• pp.16-22
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• 2016

Auto ignition characteristic is an important factor for handling combustible substance and fire prevention. This research studied about auto ignition characteristic and activation energy of Ethylene Glycol (EG) and Diethylene Glycol (DEG) by using ASTM D2155 type ignition temperature measuring apparatus. As the auto ignition temperatures, it was possible to get $434^{\circ}C$ for EG within sample amount range of $75{\sim}160{\mu}l$ and $387^{\circ}C$ for DEG within sample amount range of $130{\sim}150{\mu}l$. Also, it was possible to get $579^{\circ}C$ and $569^{\circ}C$ as instantaneous ignition temperatures with sample amount of $140{\mu}l$ for EG and DEG respectively. By using least square method from Semenov equation on measured ignition temperature and ignition delay time from this study, it was possible to calculate activation energy of EG as 25.41 Kcal/mol and DEG as 14.07 Kcal/mol. Therefore, it was possible to claim that DEG has more risk of auto ignition since the auto ignition temperature, instantaneous ignition temperature and activation energy of DEG is lower than EG.

• Fire Science and Engineering
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• 제24권2호
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• pp.76-81
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• 2010

For the safe handling of toluene, explosion limit at $25^{\circ}C$ and the temperature dependence of the explosion limits were investigated. And flash point and AIT (Autoignition Temperature) for toluene were experimented. By using the literature data, the lower and upper explosion limits of toluene recommended 1.13 vol% and 7.9 vol%, respectively. In this study, measured the lower and upper flash points of toluene by air-blowing tester were $5^{\circ}C$ and $40^{\circ}C$, respectively. And measured the upper flash points of toluene by Setaflash tester was $41.5^{\circ}C$. This study measured relationship between the AITs and the ignition delay times by using ASTM E659-78 apparatus for toluene, and the experimental AIT of toluene was $547^{\circ}C$. The new equations for predicting the temperature dependence of the explosion limits of toluene is proposed. The values calculated by the proposed equations were a good agreement with the literature data.