• 제목/요약/키워드: Airtight characteristics

검색결과 25건 처리시간 0.024초

벼의 공기 밀폐저장 특성 (Airtight Storage Characteristics of Rough Rice)

  • 금동혁;김훈;김동철
    • 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.

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220V/100W 백열전구의 온도특성에 따른 화재분석에 관한 연구 (A Study on Fire Analysis According to Temperature Characteristics of an Incandescent Electric Lamp at 220V/100W)

  • 송길목;한운기;김영석;최충석
    • 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.

사일리지의 연간급여와 사료성분의 안정성 (Year-long Feeding of Silage and Stability of Feed Quality)

  • 성경일
    • 한국초지조사료학회지
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    • 제12권1호
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    • pp.19-25
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    • 1992
  • This experiment was conducted to investigate chemical composition change and fermentation characteristics of orchardgrass, alfalfa or corn silage in the airtight silo for one year of storage. Two trials were conducted for two years. Fermentation characteristics of silages were evaluated by color, oder, texture and taste. Chemical composition of corn silage was not changed, and fermentation characteristics of this silage was favorable for 7 months of storage from December to June of the following year. In the aspect of dry matter loss and fermentation characteristics of silages, it is essential to maintain less than 70 or 60% of moisture contents in orchardgrass silage or alfalfa silage, respectively, for long term storage and feed quality stabilization. It is suggested that wilting treatment of orchardgrass or alfalfa and moisture contents of these silages are most important factors to determine silage quality.

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사일리지의 연간급여와 사료성분의 안정성 (Year-long Feeding of Silage and Stability of Feed Quality)

  • 성경일
    • 한국초지조사료학회지
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    • 제12권1호
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    • pp.19.1-19.1
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    • 1992
  • This experiment was conducted to investigate chemical composition change and fermentation characteristics of orchardgrass, alfalfa or corn silage in the airtight silo for one year of storage. Two trials were conducted for two years. Fermentation characteristics of silages were evaluated by color, oder, texture and taste. Chemical composition of corn silage was not changed, and fermentation characteristics of this silage was favorable for 7 months of storage from December to June of the following year. In the aspect of dry matter loss and fermentation characteristics of silages, it is essential to maintain less than 70 or 60% of moisture contents in orchardgrass silage or alfalfa silage, respectively, for long term storage and feed quality stabilization. It is suggested that wilting treatment of orchardgrass or alfalfa and moisture contents of these silages are most important factors to determine silage quality.

김치 발효 시 용기의 종류가 세균 생장에 미치는 영향 (The Effect of Container Types on the Growth of Bacteria during Kimchi Fermentation)

  • 한국일;김미정;권현정;김용현;김완종;한만덕
    • 한국식품영양학회지
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    • 제26권2호
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    • pp.249-257
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    • 2013
  • This study is being performed to confirm the container effects during the fermentation processes of kimchi. Kimchi fermentation was prepared in the laboratory with four different types of containers; namely, a traditional Onggi vessel (Korean traditional clay pot, TOV), plastic airtight covered Onggi vessel (PAOV), plastic covered vessel (PCV) and plastic airtight covered vessel (PACV). The kimchi fermentation in the different containers was followed by taking samples at 48 hour intervals for 10 days. In all fermentation containers, the pH changes of kimchi were decreased with fermentation days, while salt content was the same for all types of containers. The number of lactic acid bacteria in kimchi were $1.09{\times}10^8$ $CFU/m{\ell}$ at first. But the TOV, PAOV, PCV, and PACV after fermentation for 10 days were $1.42{\times}10^{10}$, $9.13{\times}10^9$, $4.93{\times}10^9$ and $7.46{\times}10^9$ $CFU/m{\ell}$, respectively. The kimchi fermented in the TOV with the most dominant bacterial species were the following 5 strains: Bacillus subtilis, B. licheniformis, B. safensis, Lactobacillus brevis and B. pumilus. The use of different types of containers therefore influenced the number of L. brevis and the four Bacillus species. in kimchi, and may influence the characteristics of the fermented kimchi products. The TOV offered the greatest L. brevis numbers and suggested that it could be the best suited for preparing traditional kimchi fermentation.

다구치 법을 통한 다이슬라이드식 사출성형의 공정파라미터 최적화 (Optimization of Process Parameters of Die Slide Injection by Using Taguchi Method)

  • 정수진;문성준;정선경;이평찬;문주호
    • Korean Chemical Engineering Research
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    • 제50권2호
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    • pp.264-269
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    • 2012
  • 플라스틱 제품의 다이슬라이드식 사출성형은 기존 사출공법의 부가공정을 삭제하여 제품 생산에 요구되는 비용과 시간을 현저히 줄여준다. 그러나 다이슬라이드식 사출성형은 사출제품의 백화, 수지침투, 기공, 수지넘침 등의 결함들을 해결해야한다. 본 연구에서는 사출성형의 공정파라미터들을 유한요소법과 다구치법을 사용하여 최적화하고자 한다. 사출 성형해석은 Moldflow insight 2010 코드로 해석하며 2차 사출에서는 다단 사출코드를 적용한다. 폴리프로필렌(PP)을 밀폐용기인 냉각수 보조탱크로 성형할 때 사용하는 공정파라미터들은 다구치법의 망소특성과 $L_{16}$ 직교배열을 사용한 실험계획을 통해 최적화된다. 한편 최적값은 유의수준 5% 수준의 분산분석을 통해 타당성을 검증한다. 그리고 최적화 조건에서 성형된 제품과 기존 제품의 치수정확도를 비교한 결과 치수안정성이 5% 이상 개선됨을 확인하였다.

살균 및 저장조건을 달리한 백삼분말의 색 특성 (Color Characteristics of White Ginseng Powder As Influenced by Different Conditions of Sterilization and Storage)

  • 권중호;변명우;이수정
    • Journal of Ginseng Research
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    • 제18권2호
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    • pp.128-133
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    • 1994
  • Color characteristics were investigated for white ginseng powder immediately and during storage following treatments of gamma ray or ethylene oxide (EO) for microbial decontamination. The variation in fatand water-soluble pigments of the sample was negligible immediately after both treatments, however an apparent increase was observed in the samples stored for four months at $25^{\circ}C$ and RH 90%, in the order of nontreated control, EO-fumigated, and 5 key-irradiated samples. Hunter's color a and b values of white ginseng powder increased slightly in proportion to irradiation doses, whereas EO fumigation caused a decrease in L value and an increase in a and b values of the sample, showing overall color difference (${\delta}^E$) of 1.8. Considering the higher ${\delta}^E$ in the higher RH conditions, airtight packaging and sterilization using like gamma ray were considered an effective means for maintaining high quality of color characteristics in stored white ginseng powder.

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실험실 실험을 통한 창의 차음성능 개선에 관한 연구 (A Study on the Enhancement of the Sound Insulation Performance of Windows through the Laboratory Tests)

  • 김선우;정진연;이옥균;장현충;박현구;송혁
    • 소음진동
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    • 제11권2호
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    • pp.307-314
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    • 2001
  • This study aims to provide fundamental data for enhancing the sound insulation performance of windows. For this study, windows composed of various types and thicknesses, were classified into five categories; fixed, single, double, triple and airtight, and then tested. In order to analyze their sound insulation characteristics and performances. test results were rated using methods such as D, STC, Ts and arithmetical mean. It was found that the sound insulation performance of windows is affected due to their type rather than the thickness of the glass. It was also found that when gap between the inner and outer frames was filled with caulking material, the sound transmission loss at high frequency bands was greatly improved. Therefore, the sound insulation performance of windows would be enhanced by minimizing the gap between frames.

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무시멘트 경량패널 심재의 혼입재료 종류에 따른 유동 및 밀도, 흡수율 특성 (Strength and Density Properties according to mixing materials types of Non-cement light weight Panel core)

  • 경인수;김태현;이동훈;이상수
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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    • pp.28-29
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    • 2017
  • Recently, the tendency of the insulation of buildings to be important is making the buildings airtight. However, in order to get closer to the technology, it is necessary to improve the performance of walls and panels of buildings, but it is a problem due to the increase of the unit price. We will review the basic data on the density and table flow characteristics of high thermal insulation materials.

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