• 한국포장학회지
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• 제14권2호
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• pp.57-63
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• 2008

The effects of airtight containers and zipper bags on the freshness extension of pine nuts (Pinus koraiensis) were studied at 4 and $25^{\circ}C$. Changes in total microbial growth, 2-thiobarbituric acid(TBA), color, and sensory quality were evaluated during storage. Total bacterial counts of the samples continuously increased over 28 days for airtight containers and 56 days for zipper bags, and then decreased at 70 days because the lack of air could affect the inhibition of the aerobic microbial growth. However no significant differences were observed between airtight containers and zipper bags. TBA values continuously increased with storage time, but there were no significant differences between the airtight containers and zipper bags during storage. Color changes and sensory evaluation analyses showed that the data revealed similar results for both packaging systems over the storage time. Therefore, it has been concluded that airtight containers and zipper bags could be used as a good packaging system to extend the shelf life of pine nuts by controlling the microbial growth, but the packaging systems of the airtight containers and the zipper bags was not significantly affect the quality parameters for 2-thiobarbituric acid(TBA), color, and sensory quality.

• 한국식품영양과학회지
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• 제23권2호
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• pp.268-273
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• 1994

The quality of Kimchi was investigated under airtight and ventilating conditions. At 2$0^{\circ}C$ and 4$^{\circ}C$ fermentation, there were no significantly difference in pH, acidity and vitamin C of Kimchi between airtight and ventilating conditions. The contents of $CO_2$ , the number of lactic acid bacteria and the sensory score of carbonated taste under airtight condition were higher than those values under ventilating condition. While , the number of aerobic bacteria under airtight condition was lower than those under ventilating condition.

• Journal of Biosystems Engineering
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• 제25권1호
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• pp.33-38
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• 2000

This study was performed to investigate airtight storage characteristics of rough rice using airtight flexible pve container. A storage test of rough rice of 4 tonnes was carried out to determine the changes of gas composition of air in the container, grain moisture content, air temperature and relative humidity , the presence of insects ,germination rate, crack ratio , fat acidity , 1000-kernel weight, and brown rice recovery over storage period of 5 months in Suwon. Concentration of oxygen was decreased from 20% to 16% and carbon dioxide was increased of from 0.03% to 1.6%. The grain moisture content was decreased from 14.4%(w.b) to 14.1%(w.b) for 5 months storage period . Insect population levels were low but these increased after 5 months storage. Most of insects were dead, Fat acidity increased from 7.5(mg KOH/100g) to 10.2(mg KOH/100g). Other storage factors such as germination rate, brown rice recovery and 1000-kernel , and 1000-kernel weight slightly decreased and crack ratio was slightly increased. Qualities of rough rice during 5 months storage period under hemetic air conditions were maintained fairly good considering the above changes of quality factors during storage.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2002년도 학술대회지
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• pp.667-670
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• 2002

Vehicle's airtight integrity is a very important factor that greatly affects passenger's habitability. However, when a door is closed, the pressure in the passenger compartment increases due to the vehicle's airtight integrity. That pressurizes the eardrums of the passenger, and makes passenger unpleasant. Thus, in this study, the configurations of air ventilation hasve been investigated to reduce pressure in the passenger compartment. Truck cab is utilized to measure the pressure in the passenger compartment. Various kinds of air ventilations are considered to find out optimized pressure in truck cab when a door is closed.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1998년도 동계 학술대회 논문집
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• pp.269-275
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• 1998

• KIEAE Journal
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• 제13권2호
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• pp.13-20
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• 2013

Today, the world energy consumption in buildings occupies more than 30%. In our country, the energy consumption in buildings also occupies 25% of the entire national energy consumption. With the increasing demand of energy saving in architectural fields, there is a more interest in low-energy construction. For these low-energy housings, our country is planning to apply the energy-saving design standards at the level of passive houses in 2017. However, there is still a limitation in energy saving only with the standards on the performance of envelope in buildings. This means that unless a building is airtight even though it was well-insulated, cooling and heating energy consumption will increase due to the infiltration and leakage. Therefore, this study aims to make a comparative analysis of airtight performance by conducting a blower door test on the housings applied with passive designs, analyze the reasons why most houses fall short of the airtightness standards, and complement the airtightness problems in the inadequate parts of the buildings in order to save building energy.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.395-396
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• 2006

To manufacture a flange for a compressor with a relief groove by using powder metallurgy in order to prevent deformation to the compressor in operation, powder material for the flange is charged into a mold; an ablative member having a melting point lower than that of the powder material is positioned at a place where a relief groove is to be formed; the flange is formed by compressing the powder material and the ablative member; and the formed flange is sintered at a temperature between the melting point of the powder material and the ablative member so as to melt and remove the ablative member. It made according to the new method has more excellent strength and airtight property than the conventional one. It is analyzed that the ablative member is melted and penetrated into the flange structure during the sintering process, which results in improvement of the airtight property and increase of the strength.

• 한국식품저장유통학회지
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• 제2권1호
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• pp.163-171
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• 1995

Organoleptic qualities were evaluated putting emphasis on flavor and color of white ginseng powders which were treated with ethylene oxide(EO) and gamma radiation(5, 10kGy) for microbial decontaminations. Immediately after treatments, there was no significant changes in the overall flavor and color of the samples between the nontreated control and both treatments. The color of even airtight-packaged samples, however, was changed(p<0.05) after 7 months of storage at 30$\pm$2$^{\circ}C$ when treated with EO and 10 kGy. These changes in color were confirmed by the instrumental determinations for the stored samples. Thus, it can be proposed that gamma Irradiation below 10kGy combined with airtight packaging is required for keeping the organoleptic quality of white ginseng powders for more than 6 months of storage.

• 한국화재소방학회논문지
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• 제20권1호
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• pp.43-49
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• 2006

본 논문은 조명설비 중 220V/100W 백열전구의 온도특성과 화재분석에 관하여 연구하였다. 백열전구의 발열에 의한 발화가능성을 실험한 결과 정상상태에서는 최고 $161.9^{\circ}C$로 측정되었다. 밀폐된 공간에서 축 열이 되면 약 $538.1^{\circ}C$까지 상승하는 것으로 나타났다. 유리구를 파손하였을 경우 필라멘트는 공기 중에서 용단되었다. 외부 열에 의한 경우 전구 내부의 가스가 약한 부분으로 분출되었다. 따라서 백열전구는 산소의 공급이 원활하면서 폐쇄된 공간에서 화재의 가능성이 높으며, 가연성 물질 등이 주변에 있다면 화재 가능성이 매우 높은 것으로 나타났다. 백열전구의 외형변화, 재료특성의 변화 등을 통해 화재원인을 규명하는 중요한 자료로 이용될 것이 기대된다.

• 생물환경조절학회지
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• 제31권3호
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• pp.212-220
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• 2022

장미의 단일 마디 삽목의 경우 온도, 상대 습도 및 광과 같은 환경 관리가 생산성에 영향을 미친다. 기온과 상대습도가 삽목 성공률과 묘 소질에 미치는 영향을 조사하기 위해 장미(Rosa hybrida) 'Maisie' 품종과 투명한 플라스틱 박스를 이용하였으며 인공조명(white LED, PPFD 104.0µmol·m^-2·s^-1)을 이용하여 전 기간 밀폐 조건에서 삽목 시 가장 효과적인 소엽수와 광주기 조건을 구명하고자 하였다. 첫 번째 실험은 밀폐 기간을 달리하여 총 6주 동안 진행되었다. 밀폐 기간이 길어질수록 뿌리수와 가장 긴뿌리의 길이가 감소하였다. 그러나 밀폐 기간에 따른 생존율, 신초발생률, 발근율에 유의한 차이가 없었다. 두 번째 실험에서는 삽수 생존율과 신초발생률이 광주기(0/24, 2/22, 4/20, 8/16, 16/8h)와 삽수 소엽의 개수(0, 2, 4)에 의해 영향을 받는 것으로 나타났다. 생존율은 명기 16시간, 소엽 4개 처리구에서 가장 높았다. 생존율과 신초발생률을 에너지 효율과 함께 고려한 결과, 소엽을 2개 또는 4개 붙인 삽수를 이용하여 하루 8시간 광을 조사하는 것이 가장 효과적인 것으로 판단되었다.