• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.2292-2297
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• 2008

Recently, a study on condensers for refrigerators has focused on new model which will cost less and will be more efficient. Some widely used condensers for domestic refrigerators are wire-and-tube type condenser, hot-wall type condenser, and spiral type condenser. Some companies which use the spiral type condenser at the moment try to develop a new type condenser which will cost less and will be as efficient as the spiral type. The new type condenser consists of a steel tube, steel plates and louver fins attached to the tube. The tube and the plate are bent into a single-passage serpentine shape.

• 한국식품과학회지
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• 제28권4호
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• pp.632-637
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• 1996

가정용 냉장고의 냉장실 온도는 통상 $4^{\circ}C$를 적용하고 있으나, 냉장온도를 $2^{\circ}C$로 낮추고, 온도 편차를 줄일 경우 저장효과의 향상 정도를 비교하기 위하여, 각각 다른 조건에 저장한 과일과 어패류의 품질을 비교 측정하고 아울러 냉장온도에서 생육이 가능한 미생물의 생육정도를 비교하였다. 냉장 온도를 $2^{\circ}C$로 낮추고 온도 편차를 ${\pm}0.3^{\circ}C$ 정도로 낮춘 경우 사과의 경도는 저장 14일째까지 크게 변화하지 않았으나, $4^{\circ}C$의 냉장고에서는 7일 이후 경도가 서서히 감소하는 것으로 나타났으며, 도미의 근단백질 분해 정도 또한 $2^{\circ}C$에서는 느리지만, 저장온도가 높거나 온도편차가 심할 경우 근단백질의 분해가 빨리 나타나 도미의 신선도가 빨리 저하됨을 보여 주었다. 굴의 저장 중 미생물수의 변화는 $2^{\circ}C$에서는 저장 9일째까지 균수의 증가를 보이지 않은 반면, 저장온도가 $4^{\circ}C$인 경우 저장 5일 이후 급격한 증가를 보였고, pH 저하 또한 $2^{\circ}C$에서는 비교적 완만하였으나 $4^{\circ}C$에서는 급격히 저하되었다. Listeria monocytogenes는 우유 중에서는 $2^{\circ}C$에서도 성장하였으나, 햄에서는 냉장온도가 $2{\pm}0.3^{\circ}C$인 경우 증식이 억제되어 생존 균수가 감소하였고, $4{\pm}1.2^{\circ}C$인 경우 약간 성장하였고, 온도 편차가 보다 심한 $4{\pm}4^{\circ}C$에서는 성장이 지속되어 생존균수의 증가를 보여 주었다. 따라서 냉장온도를 $2^{\circ}C$로 낮추고 온도의 편차를 줄임으로써 과일이나 어패류의 저장기간을 보다 연장시키고 유해 미생물의 증식이 상당히 억제될 수 있으리라 기대된다.

• KEPCO Journal on Electric Power and Energy
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• 제2권2호
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• pp.299-305
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• 2016

초전도 전력 케이블의 상용화 노력에 따라 점차 장선화 되면서, 단위 냉각 시스템당 냉각용량이 큰 대용량 냉동기의 필요성이 증가하고 있다. 국내에서는 극저온 냉동기에 대한 기술 부족으로 인해 현재 극저온 냉동기는 해외 선진사로부터 고가의 비용으로 수입되고 있다. 초전도 전력 케이블의 상용화를 위해서는 대용량 브레이튼 냉동기의 국내 개발이 시급하다. 대용량 브레이튼 냉동기의 구성은 복열식 열교환기, 압축기, 극저온 터보 팽창기로 구성되어 있으며, 냉동기 효율과 가장 직접적인 연관이 있는 것은 극저온 터보 팽창기이다. 극저온 터보 팽창기는 극저온에서 고속으로 회전하면서 고압의 헬륨 혹은 네온 가스를 팽창시켜 온도를 낮추는 역할을 한다. 본 논문에서는 역브레이튼 냉동 사이클을 설계하고, 이에 적합한 극저온 터보 팽창기를 설계하였다.

• 동력기계공학회지
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• 제17권3호
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• pp.65-71
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• 2013

The under rail slide is the latest device to make accurate rectilinear reciprocating motion. In these day, 3-point type is used mostly for the products requiring high strength and performance such as refrigerator door guide or furniture drawer guide. However, It is all imported from foreign countries due to lack of the roll forming technique to make 3-point type under rail slide in domestic. Therefore, design and manufacturing technology for the 3-point type under rail slide are need to development through systematic study. In this paper, to make center member of 3-point ball-type under rail slide for the refrigerator doors, the roll forming modeling and simulation are performed using Shape-RF software. Tensile test is performed about SCP-1 1/2H for determine the mechanical properties of materials. Interference between the roll and the final shape are predicted from the results of the simulation ; this result show that the desirable performance and usefulness of the designed roll forming process.

• 한국기계가공학회지
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• 제15권6호
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• pp.70-76
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• 2016

Commercialization of surface lighting using Light Emitting Diodes (LED) has embraced the advance to Organic Light Emitting Diode (OLED) technology. This is necessary to achieve light-efficiency-improvement and longer component life. The range of application of LED lighting for both interior and outdoor lights has been gradually expanding. Automobiles and home appliances are now included. In the case of LED surface lighting in a domestic refrigerator, achieving high efficiency requires optimization of the number of LEDs in a pack. Optimization is also required in the design stage of development with regard to the conversion of the light source type from point light sources to the surface light type. This paper addresses these design problems. It presents a study of brightness variations for design solutions that differ from the existing technology in both the number of LED packages and use of Light Gathering Power (LGP) information. The intention is to facilitate production of high brightness LED surface lighting for domestic refrigerators.

• 동아시아식생활학회지
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• 제14권4호
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• pp.319-337
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• 2004

The purpose of this study was to investigate the dietary life about Kimchi of the housewives. Self-administrated questionnaires were completed by 322 housewives in Wonju area. The results were as follows: In the point of housewives' domestic duties, over 50% of housewives took care of their domestic duties alone, and the rate who learned how to manage domestic duties from their mothers before marriage decreased as the age got younger. 77.6% of housewives responded that both man and woman could manage a dietary life at home in the future, and the rate of such response was higher as their educational careers were higher and they were younger. In the point of housewives' basic situation about Kimchi, the rate of housewives who knew how to prepare kimchi was high as they were older, and the holding rate of a refrigerator for Kimchi was high as much as 72.4%. In the point of preparation for Kimchi, the rate who made Kimchi by themselves was high, but the rate of preparing Kimchi by their parents for them was higher in the twenties. Frequency of making Kimchi, an amount or a kind of Kimchi were notably different according to housewives' age, a type of their family, the number of their family, and their having a job or not. Housewives' opinion of a market kimchi was that it was expensive, and not sanitary, and rate of purchasing Kimchi was also low. In the point of the prepartion method of Kimchi for the winter, the rate who gained Kimchi from their parents was higher as they lived in an apartment, and had a nuclear family, and had the lesser family members. In an amount of Kimchi prepared for the winter, 11∼22 heads were 23.9% and 21∼30 heads were 21.9%. In the point of the method preparing Kimchi in the future, 53.8% of housewives responded that they would make by themselves, and 28.0% answered they would prepare or purchase. 77.4% of housewives answered that they would teach how to make Kimchi to their children. In conclusion, in housewives of Wonju area, wanted to make Kimchi by themselves and wanted their children to learn how to make Kimchi.

• 한국식품위생안전성학회지
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• 제23권4호
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• pp.304-308
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• 2008

본 연구는 주요 냉장식품(두부, 묵, 어육가공품(어묵), 생면, 김초밥, 샐러드)의 온도 관리실태를 조사하여 문제점을 파악하고 국내 유통업소의 냉장 냉동진열 판매 제품의 관리온도 개선 및 관리방안을 제시하고자 하였다. 주요 냉장고 내 위치별 온도는 보편적으로 아래($7.5^{\circ}C$)가 높고 윗부분($6.4^{\circ}C$)이 낮았으며, 앞쪽($8.9^{\circ}C$)이 높고 뒤쪽($7.5^{\circ}C$)이 낮은 것으로 조사되었다. 모든 냉장식품의 평균 냉장고 보관 온도는 $7^{\circ}C$(최대 $22.9^{\circ}C$, 최저 $-2^{\circ}C$)였으며, 대형할인매장이 $6.5^{\circ}C$,백화점이 $7.5^{\circ}C$, 편의점이 $7.6^{\circ}C$ 였다. 모든 냉장식품의 평균 표면온도는 $8.2^{\circ}C$(최대 $19^{\circ}C$, 최저 $-0.4^{\circ}C$)였으며, 대형할인매장이 $8.1^{\circ}C$,백화점이 $8.5^{\circ}C$, 편의점이 $7.6^{\circ}C$으로 조사되었다. 식품표면과 중심온도는 식품별 차이가 있으며 최대 $2.3^{\circ}C$ 차이로 나타났다. 두부(표면온도 $6.1{\sim}10.6^{\circ}C$, 중심온도 $4{\sim}11.1^{\circ}C$), 어묵($6{\sim}12.3^{\circ}C$, $6.5{\sim}13.6^{\circ}C$), 김밥($2.3{\sim}18.2^{\circ}C$, $2{\sim}17.3^{\circ}C$), 샐러드류($4.6{\sim}12.2^{\circ}C$, $4.1{\sim}10.4^{\circ}C$), 생면류($3.4{\sim}12.6^{\circ}C$, $3.8{\sim}10.3^{\circ}C$), 묵류($7.1{\sim}19^{\circ}C$, $8.3{\sim}17.1^{\circ}C$)의 다섯 가지 식품별로 차이를 보였다. 냉장고 표시온도와 식품표면 온도 항목간의 유의적 차이가 있는 것으로 나타났다(P<0.01). 냉장고 표시 온도는 김밥 1곳(100%)에서 규정온도인 $10^{\circ}C$를 초과했지만, 식품표면 온도에서는 두부 9곳(17%), 어묵 6곳(11.3%), 묵 10곳(18.9%), 생면 11곳(20.8%), 김밥 13곳(24.5%), 샐러드 4곳(7.5%)이 초과한 것으로 나타났다. 결론적으로 우리나라 냉장보관 식품 중 표면온도와 $10^{\circ}C$를 초과하는 경우가 많아 냉장보관식품의 온도관리가 철저히 이루어져야 할 것으로 판단된다.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2004년도 하계학술발표 논문집
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• pp.46-46
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• 2004

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2009년도 춘계학술대회 논문집
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• pp.321-323
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• 2009

When power failure occurs at multi-housing complex, auxiliary generator or emergency generator starts to provide power to households. This power is connected to emergency power ELB(Earth Leakage Breaker) at home distribution panel board and supplies power only for emergency light in living room but for heating system, refrigerator and other inevitable apparatuses that are in need of uninterruptible power. Since those domestic appliance are fed from common power line, they are inoperable during power failure. Our research is to resolve this problem by developing compatible relay-drive common/emergency-power ATS (automatic transfer switch) for home distribution panel board. In case of power failure, it transfers automatically and commences to provide power from emergency generator. Through this, Consumers can reach satisfaction where common power loads operate without any problem under both ordinary and power failure condition.

• 설비공학논문집
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• 제17권1호
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• pp.62-70
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• 2005

In this study, the air-side heat transfer coefficients of several types of evaporators in the household freezer/refrigerators are investigated. The types considered in this work are: discrete flat plate fin-and-tube type(in-lined tube array), continuous flat plate fin-and-tube type(staggered tube array), and spine fin-and-tube type(in-lined tube array). The heat transfer correlations obtained from this study for each heat exchangers could expect heat transfer coefficients less than $5\%$ of errors. The result indicates that the air-side heat transfer performance of spine fin-and-tube type evaporator shows the highest value under dry conditions, but discrete flat plate fin-and-tube type evaporator shows the highest value among these three evaporators under frosting conditions.