• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2002.02a
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• pp.401-406
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• 2002

식물조직 배양공정의 기계화 기술개발을 위한 기초자료를 얻고자 식물조직 배양기술의 개발 또는 식물묘를 대량생산하는 연구지도기관 및 농원 등의 배양실 10개소를 대상으로 배지의 분주, 배양용기의 밀봉 및 세척, 배양체의 접종공정 등에 대한 작업실태를 조사분석한 결과를 요약하면 다음과 같다. 가. 배양기술의 개발 또는 식물묘 대량생산은 대부분이 나리, 호접란, 풍란, 심비디움 등 화훼류였으며, 배지는 모두 한천이 혼합된 고체배지, 배양용기는 형상 및 용량 등이 다른 플라스크, 배양병, pE용기 등이 사용되었다. 나. 배지의 분주작업은 조사대상 10개배양실중 6개소는 작업자가 비이커를 사용하여 분주하였고 4개소는 자동 또는 반자동분주기를 사용하였으며, 인력 및 반자동분주기의 사용시 배양용기간의 분주량은 기준량의 $\pm$25%범위에서 차이가 있었다. 다. 액체배지의 분주시 온도는 36.8~88.$0^{\circ}C$, 점도는 3.7~11.8cP 범위였고 점도는 배지에 혼합하는 한천, 사과 등 유기물의 량에 따라 차이가 있으므로 배지의 분주작업을 기계화하기 위해서는 배지의 온도와 점도, 배양용기와 분주량 등을 종합적으로 고려하여 배지의 점도에 따라 분주량을 조절할 수 있도록 개발할 필요성이 있다고 생각된다. 라. 배양용기의 밀봉소재는 플라스크의 경우 호일 또는 고무마개와 호일, 배양병은 모두 나사산이 있는 캡, PE용기는 뚜껑을 사용하였으며, 밀봉작업은 모든 배양실에서 인력에 의존하였고 작업능률은 호일만으로 밀봉하는 경우 시간당 180~240병, 캡은 시간당470~600개 정도였다. 마. 배양체의 접종작업은 모든 배양실이 인력에 의존하였으며, 배양체를 배지와 분리하여 불필요한 부분을 제거하고 배양작물에 따라 생육정도를 2~3등급으로 구분하여 배양용기의 배지 위에 치상하는 과정으로 수행되었으며, 작업능률은 호접란의 경우 배양병에 25본을 접종하는데 시간당 6병, 심비디움은 원형 플라스크에 25본을 접종하는데 시간당 10병 정도였다. 바. 식물체의 대량증식에 사용되는 플라스크, 배양병, PE용기 등 배양용기의 세척작업은 농원의 1개배양실에서 간이식 세척기, 이 외의 9개배양실은 모두 물에 담겨 두었다가 세제와 브러쉬 등을 사용하여 인력으로 세척하고 있어 생력화 기술개발이 요구되었다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.305-305
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• 2007

SOFC용 밀봉유리$({\sim}10.0{\times}10^{-7}/K)$의 열팽창 계수를 SUS430$({\sim}12.0{\times}10^{-7}/K)$ 인터커넥터에 매칭 시키기 위하여 모유리에 비하여 열팽창계수가 큰 $CaTiO_3\;({\sim}13.5{\times}10^{-7}/K)$ 입자를 필러로서 첨가하였다. 필러입자의 첨가량이 증가함에 따라 밀봉재의 열팽창 계수가 증가하고, 동일 함량의 필러를 첨가하는 경우 필러 입자의 크기가 작을 수록 밀봉재의 연화점 상승 폭이 커서 SUS430 기판과의 접합 상태가 불량해짐을 관찰하였다. 필 테스트, 접합시험, 미세구조 분석 등을 통하여 필러 입자 크기가 증가 할 수록 SUS430과의 접합이 가능한 범위 내에서 보다 많은 양의 필러를 첨가하는 것이 가능하기 때문에 열팽창 계수 제어가 용이하다는 것을 확인 할 수 있었다.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.16 no.4
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• pp.479-490
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• 2018

The granite melting concept, which was suggested by Gibb's group for the closing of a deep borehole, was experimentally checked for KURT granite. The granite melting experiments were performed in two pressure conditions of atmospheric melting with certain inorganic additives and high pressure melting formed by water vaporization. The results of atmospheric tests showed that KURT granite started to melt at a lower temperature of $1,000^{\circ}C$ with NaOH addition and that needle shaped crystals were formed around partially melted crystals. In high pressure tests, vapor pressure was increased by adding water with maximum pressure of about 400 bars. KURT granite was partially melted at $1,000^{\circ}C$ when vapor pressure was low. However, it was not melted at vapor pressures higher than 200 bars. Therefore, it was determined that high pressure with a small amount of water vapor more effectively decreased the melting point of granite. Meanwhile, high temperature and high pressure vapor caused severe corrosion of the reactor wall.

• Food Science and Preservation
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• v.19 no.5
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• pp.626-632
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• 2012

In this study, the changes that occurred in the quality of minimally processed sliced Deodeok (Codonopsis lanceolata) in relation to the packing method during storage at $7^{\circ}C$ were investigated. The storage tests were conducted for seven days using PE sealing, but PP sealing and vacuum packaging preserved the Deodeok for 14 days. On the seventh day, the vinyl-packaged Deodeok showed a remarkable fall in quality with 4.5 °Brix, but the PP-sealed and vacuum-packaged Deodeok showed slight falls with 6.4 and $6.8^{\circ}Brix$, respectively. The PE- and PP-sealed Deodeok did not show significant differences in texture and moisture content for two days, and the moisture content was highest in the vacuum-packaged Deodeok during storage. In relation to the total viable cell and the coliform count, the vacuum-packaged Deodeok showed the lowest rate of increment during storage, followed by the others. Thus, the bubble-washed and vacuum-packaged minimally processed sliced Deodeok was found to have the best quality.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.2
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• pp.133-138
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• 1991

Several quality indices of Shiitake mushroom (Lentinus edodes) were measured during storage at modified atmosphere (MA) conditions made by plyethylene film bag with different thicknes. IN the mushrooms kept in the thicker film bag, larger amounts of ethyl alcohol and acetaldehyde were produced during storage. The lowest weight loss was marked by the mushrooms kept in 0.06mm thick film bag. Protein content of the mushrooms was increased with the storage period without any storage period without any significant trend depended on the storage treatments and electrophoresis pattern of protein was changed little in the mushrooms kept in 0.04mm thick P.E. film bag during storage.

• Journal of the Korean Institute of Gas
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• v.11 no.1 s.34
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• pp.23-28
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• 2007

This paper presents an experimental investigation on the sealing defects and cracks of O-rings and a valve packing of a gas valve for a LPG cylinder. O-ring in which stops a gas leakage of a liquefied petroleum gas is very important for a LPG valve safety. Valve packing is to open and close a gas flow port for supplying and charging a LPG fuel. The sealing performance of two sealing units ism related to the leak safety and long lift of a gas valve. The investigated results show that most of O-rings was failed due to a circumferential crack in which is caused by partial press bonding failure near the partition zone and an excess compression rate. Some of the O-ring failure was originated by an extrusion of an excessive leak pressure of a LP gas. Thus, this paper strongly recommends a tight quality control and a safety guarantee system of O-rings and valve packing to guarantee a leak safety and to extend a service lift of a gas valve. At the end, a warranty policy of the sealing units should be adopted for increasing a product quality and safety of a gas valve.

• Applied Chemistry for Engineering
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• v.19 no.4
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• pp.382-387
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• 2008

$Ba_{0.5}Sr_{0.5}Co_{0.8}Fe_{0.2}O_{3-{\delta}}$ oxide was synthesized by polymerized complex method. Dense membrane of perovskite oxide was prepared using as-prepared powder by pressing and sintering at $1080^{\circ}C$. Leakage test was conducted on the membrane sealed by gold ring, Pyrex ring or Pyrex powder as a sealing material. The oxygen permeation flux of $Ba_{0.5}Sr_{0.5}Co_{0.8}Fe_{0.2}O_{3-{\delta}}$ membrane increased with increasing temperature and was $0.74mL/min{\cdot}cm^2$ at $900^{\circ}C$. In the case of the membrane applied by sealing material, oxygen permeation flux of the membrane using gold ring at $950^{\circ}C$ was higher than that using Pyrex materials because the undesired spreading of Pyrex glass materials in the membrane led to the reduction of effective permeation area. Microphotograph analysis results for the membrane after permeation test confirmedthe diffusion of Pyrex glass seal into the membrane.

• Food Science and Preservation
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• v.8 no.4
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• pp.367-373
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• 2001

In order to study the effect of modified atmosphere storage on extending shelf life of King Oyster mushroom was wrapped with PVC film and packed with 20$\mu\textrm{m}$polyolefin(PD941), and effects of temperature(0, 5, 10$^{\circ}C$) in packaging conditions on the respiration and keeping qualities were evaluated. Higher respiratory activity and weight loss were observed at higher temperature. The concentration of O$_2$and CO$_2$ of PVC wrap and polyolefin(PD941) packages for all showed 1∼2% and 10∼14%, respectively. Polyolefin(PD941) package wan superior to the PVC wrap packaging method in Hardness, Hunter L value, Hunter b value and sensory qualities, and reducing weight loss at 0$^{\circ}C$, 5$^{\circ}C$ and 10$^{\circ}C$ compared to PVC wrap. It was found that the optimum shelf-life period of King Oyster mushroom packaged by PVC wrap was estimated to be 50, 28 and 12 days at 0, 5 and 10$^{\circ}C$, respectively, and 50, 32 and 21 days in Polyolefin(PD941).

• Nuclear industry
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• v.35 no.3
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• pp.82-83
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• 2015

• Nuclear industry
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• v.29 no.3
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• pp.144-147
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• 2009