• 설비공학논문집
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• 제11권3호
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• pp.301-312
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• 1999

Experiments were carried out to evaluate performance of the cold air distribution systems with an ice storage tank in test room. Cold air distribution systems provide primary air for comfort conditioning or process cooling at coil discharge temperatures$4^{\circ}C$ to$11^{\circ}C$. The application of a cold air distribution system allows for the downsizing of air distribution equipment and central plant equipment when ice storage tank is used. The benefit of a cold air distribution system include a decrease in the floor-to-floor height, increase floor space, reduced building capital costs, reduced energy use and demand. The use of cold air distribution can result in the most cost effective system and is currently being implemented world wise as the new standard in air conditioning systems. In this study, the cold air distribution system is compared with the general ice storage system. Under the same cooling load conditions, experimental results show that the supply air volume of cold air distribution system decrease 38%, and decrease 45% flow rate of brine for the general ice storage system.

• 한국정보통신학회논문지
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• 제15권9호
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• pp.1971-1978
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• 2011

기존의 RFID (Radio Frequency Identification) 기반 냉동창고 시스템에서는 cold room 입구에 RFID 리더기를 설치하여 물품이 인식될 때 단지 그곳에 적재되는 것으로 인식하였다. 그러나 이러한 방법으로는 다양한 상황에서 물품의 적재위치 인식에 오류가 발생하게 된다. 냉동창고에서는 물품 보관을 하는 cold room의 안팎 온도차이로 인해 물품의 적재위치 오류는 물품의 변질을 가져오게 하므로 실시간 정확한 위치를 파악하는 것은 매우 중요하다. 본 논문에서는 2대의 RFID 리더기가 설치된 지게차와 천정태그를 이용하여 냉동창고 관리시스템에서 물품의 적재위치 오류를 해결하기 위한 방안을 제시한다. 지게차에 설치된 2개의 RFID 리더기는 각각 천장에 부착된 태그로부터 위치데이터와 지게차에 적재된 물품데이터를 획득한다. 2개의 리더기로부터 수집된 데이터를 분석하여 물품의 입/출고 상황정보와 물품의 이동경로정보를 실시간으로 모니터링 할 수 있다. 이를 통해 냉동창고의 물품보관에 대한 효율성을 높일 수 있게 한다.

• Journal of Dairy Science and Biotechnology
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• 제29권1호
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• pp.59-63
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• 2011

This study was carried out to investigate the change of components which raw milk has during cold storage. General component content of raw milk (fat, protein, lactose, total solids) was decreased in proportion to the length of cold storage. The pH of raw milk was decreased in according to the length of cold storage. In electrophoresis images, ${\beta}$-casein which was one of the composition of raw milk was decreased as the period of cold storage extended on the other hand, the content of Ca and P in the serum casein was increased in accordance with the length of cold storage.

• 한국응용과학기술학회지
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• 제6권2호
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• pp.75-87
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• 1989

Study to report this result that state of lipid peroxides while beef Bulgogi Coocking of general-seasoning, sale-seasoning, each flavour's characteries. Raw meat show high lipid peroxides amount and high increasing in heat and antioxidative effected by flavour about lipid peroxidies change existence by beef Bulgogi seasoning. Change of lipid peroxides are significant increased in meat cold storage and cold storage and cold storage heat meat after while 30 minute after seasoned and reduced 9 hour - 33 hour cold storage raw meat, that change of lipid peroxides by cooking time. every condition by adding soften were revealed lipid peroxides, reduce. Lipid peroxide change are very high while no-sugar in raw meat and not a stone look in 9-hour raw-meat after seasone about antioxidative effect by each flavour characteristic TBA showed very high not take parched seasone seeds item about 30-minute cold storage beat raw-meat and high lipid peroxides revealed increase in not take wine item, not take a pear item, in 9 hour cold storage heat-meal and it showed little amount not-sugar item, no opepper item. According to high lipid peroxides change reduced high after seasoned cold storage stage in Korea traditional Bulgogi Cooking and thought high that action of antioxidative lipid peroxides wine and a pear in flavour.

• Journal of Biosystems Engineering
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• 제28권2호
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• pp.117-126
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• 2003

This study was conducted to develop precision control system fur cold storage facility that could offer safe storage environment for green grocery. For that reason of neuro-fuzzy control system with learning ability algorithm and single chip neuro-fuzzy micro controller was developed for cold storage facility. Dynamic characteristics and hunting of neuro-fuzzy control system were far superior to on-off and fuzzy control system. Dynamic characteristics of temperature were faster than on-off control system by 1,555 seconds(123% faster) and fuzzy control system by 460 seconds(36.4% faster). When system was arrived at steady state. hunting was ${\pm}$0.5$^{\circ}C$ in on-off control system, ${\pm}$0.4$^{\circ}C$ in fuzzy control system, and ${\pm}$0.3$^{\circ}C$ in neuro-fuzzy control system. Hunting of humidity and wind velocity was also controlled precisely by 70 to 72.5% and 1m/s For storage experiment with onion, characteristics of neuro-fuzzy control system were tested. Dynamic characteristics of neuro-fuzzy control system made cold storage facility conducted precooling ability and minimized hunting.

• Agricultural and Biosystems Engineering
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• 제3권2호
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• pp.65-72
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• 2002

Temperature is the most influential environment parameter which affects the quality change of agricultural products in cold storage. Therefore, it is essential to keep the uniform temperature distribution in the storage room. This study was performed to analyze the air movement and temperature distribution in the forced recirculating cold storage facility and to simulate optimum storage method of green groceries using 3-D CFD(three dimensional computational fluid dynamics) computer simulation which applied the standard $textsc{k}$-$\varepsilon$ turbulence model and FVM(finite volume method). The simulation was validated by the experimental results for onion storage and the simulation model was used to simulate the temperature and velocity distribution in the storage room with reference to the change of storage method such as location of storage, no stores, bulk storage, and pallet storage. In case of no stores, internal airflow was circulated without stagnation and consequently air movement and temperature distribution were uniform. In case of bulk storage, air movement was stagnated so much and temperature distribution of onion was not uniform. Furthermore, the inner temperature of onion roses more than the initial temperature of storage. In case of pallet storage, air movement and temperature distribution of onion were so uniform that the danger of quality change was decreased.

• 한국식품저장유통학회지
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• 제3권2호
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• pp.105-111
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• 1996

The conditions of cold stroage of Citrus unshiu Marc. var. okitsu produced in Cheju were investigated. The changes of peel moisture contents soluble solids, total sugar, vitamin C and density were slightly occured, and decay ratio was below 20% on keeping freshness relatively till late of March during cold storage. After thats decayed citrus fruits were increased gradually mainly from cold injury with lower temperature and high humidity. The loss of fruit weight, decrease of fruit hardness, and decrease of acid content were occured gradually during cold stroage. Because of the difficulty of long term storage for Citrus unshiu, the conditions and periods of cold storage would be determined after considering the physicochemical properties of fruits every year.

• Journal of Microbiology and Biotechnology
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• 제32권12호
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• pp.1599-1604
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• 2022

Storage stability of freeze-dried lactic acid bacteria is a critical factor for their cost-effectiveness. Long-term storage of lactic acid bacteria enables microbial industry to reduce distribution costs. Herein, we investigated the effect of cold adaptation under supercooling conditions at -5℃ on the viability of Leuconostoc mesenteroides WiKim32 during the freeze-drying process and subsequent storage. Cold adaptation increased the thickness of exopolysaccharides (EPS) and improved the viability of freeze-dried Leu. mesenteroides WiKim32. Compared to non-adapted cells, cold-adapted cells showed a 35.4% increase in EPS thickness under supercooling conditions. The viability of EPS-hydrolyzed cells was lower than that of untreated cells, implying that EPS plays a role in protection during the freeze-drying process. Cold adaptation increased the storage stability of freeze-dried Leu. mesenteroides WiKim32. Fifty-six days after storage, the highest viability (71.3%) was achieved with cold adaptation at -5℃. When EPS-containing broth was added prior to the freeze-drying process, the viability further increased to 82.7%. These results imply that cold adaptation by supercooling pretreatment would be a good strategy for the long-term storage of Leu. mesenteroides WiKim32.

• Journal of Biosystems Engineering
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• 제32권1호
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• pp.13-19
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• 2007

Storage rough rice in low temperature using the winter cold air avoids rough rice temperature increase which happens from early May, and this is possible by installing a cooling system in the top of a bin, the room between top rice level and bin ceiling. The research objective is to establish low temperature rough rice storage technique, furnishing winter cold air to rough rice, by investigating the cooling system potential of maintaining low rough rice temperature and by analyzing rough rice storage characteristics over a storage period. The rough rice storage characteristics were evaluated from January to August 2003, using a storage and dry bin of 400-ton capacity. Results of this research are as follows: Cooling bin using the cooling system in the top of the bin maintained the rice temperature less than 15$^{\circ}C$ in entire portions in August. Moisture contents and germination rates of rough rice were decreased over the storage period, on the other hand, the rough rice stored in the ambient temperature bin had relatively lower moisture contents and germination rates to compare with the bin using winter cold air. Crack ratio and acid value of brown rice in the ambient temperature bin storage had increased more than the cooling bin storage. The result indicates that the storage bin using winter cold air and the cooling system maintains moisture content and germination of rice, minimizes cracked kernel and acid value, and preserves rice quality as well.

• 디지털융복합연구
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• 제17권2호
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• pp.101-111
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• 2019

냉동 냉장창고의 집적단지인 '콜드체인 클러스터' 구축이 물류업계의 현안으로 급부상하고 있다. 인천항만공사는 한국가스공사와 협력하여 송도 LNG 인수기지에서 발생하는 냉열 에너지를 이용한 냉동 냉장 클러스터를 구축하기 위한 사업을 진행 중에 있다. 본 연구에서는 CFPR 방법론을 활용하여 냉동 냉장 클러스터 활성화 방안을 제시하는 것을 연구의 목적으로 한다. 분석결과, 상위요인에서는 안정성과 수익성 요인이 0.281로 가장 중요시 되는 요인으로 파악되었다. 세부요인으로는 지속가능한 물동량 확보가 가장 높게 나타났고, 임대료 수준, LNG 냉열 활용기술의 지속 가능성과 일반 냉동 냉장창고와의 경쟁, 시설 중복투자 배제 등의 순으로 중요도가 평가 되었다. 향후 연구에서는 활성화 요인을 활용하여 국내 지역별 냉동냉장클러스터를 평가할 필요가 있다.