• 대한기계학회논문집
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• 제19권10호
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• pp.2647-2656
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• 1995

The present work was performed to axially and radially investigate the local cold storage performance in the cylindrical tank with the spherical capsules inserted n-Tetradecane as a new cold storage material. The local cold storage performance of the capsules in the tank was experimentally investigated for the inlet temperature of -7, -5, -3, 0.deg. C, for the flow rate of 0.95, 1.89, 2.84, 6.00 l/min, and for the diameter ratio of 4.9, 9.0, 13.1. The local cold storage performance in the case of using water applied for the commercial ice-ball system was axially investigated by changing the flow rate only with the inlet temperature of -7.deg. C and the diameter ratio of 9.0 in order to compare with the performance in the case of using n-Tetradecane. For the case of using n-Tetradecane, the difference of cold storage period between the first and the seventh story was increased as the inlet temperature was increased and the flow rate was decreased. The capsules at the center of the tank showed the supercooling and the increased cold storage period compared with the capsules at the wall of the tank due to the small porosity and insufficient cold storage performance at the center of the tank as the diameter ratio is increased. The case using water showed worse cold storage performance due to comparatively large supercooling than the case using n-Tetradecane.

• 한국자동차공학회논문집
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• 제23권4호
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• pp.428-435
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• 2015

This paper presents the experimental study of cabin thermal comfort using a cold storage heat exchanger in a vehicle air-conditioning system. Recent vehicle-applied ISG functions for fuel economy and emission, but when vehicles stop, compressors in the air-conditioning system stop, and the cabin temperature sharply increases, making passengers feel thermal discomfort. This study conducts thermal comfort evaluation in the vehicle, which is applied to a cold storage system for the climate control wind tunnel test and the vehicle fleet road test with various airflow volume rates and ambient temperatures blowing to the cold storage heat exchanger. The experimental results, in the cold storage system, air discharge temperature is $3.1-4.2^{\circ}C$ lower than current air-conditioning system when the compressor stops and provides cold air for at least 38 extra seconds. In addition, the blowing airflow volume to the cold storage heat exchanger with various ambient temperature was examined for the control logic of the cold storage system, and in the results, the airflow volume rate is dominant over the outside temperature. For this study, a cold storage system is economically useful to keep the cabin at a thermally comfortable level during the short period when the engine stops in ISG vehicles.

• 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.

• Journal of Biosystems Engineering
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• 제33권3호
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• pp.167-172
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• 2008

The objective of this study was to investigate the adequate storage method that was able to maintain the high quality of rough rice according to storage methods and period. The quality change of the rough rice during the storage period was evaluated by storage method such as cooling bin using winter cold air, ordinary temperature bin, freezing, refrigeration and indoor storage. Moisture content, brown rice whiteness, hardness, crack ratio and germination ratio were measured in this study. Moisture content of rough rice stored in cooling bin using winter cold air and ordinary temperature bin were decreased by 0.07% and 0.42%, respectively, which were lower than the other storage method. The hardness of brown rice increased in order of storage method such as winter cooling bin, normal bin, freezing storage, refrigeration storage and indoor storage. Crack ratio by indoor and ordinary temperature bin storage were increased by 2.68% and 3.63%, respectively, whereas cooling bin using winter cold air, refrigeration and freezing storage showed below 1.0%. The highest germination rate was found in cooling bin using winter cold air. As a result, cooling bin using winter cold air can be evaluated for the adequate storage method of rough rice.

• 한국가금학회지
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• 제24권1호
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• pp.17-28
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• 1997

This experiment was carried out to investigate the effects of different chilling and packing methods on physico-chernical properties of cold-stored chicken breast and thigh meats. Dehoned chicken breast and thigh meats were chilled either air spray or ice-water immersion method. The chilled meats were either vacuum packed or atmosphere packed, and stored at -2˚C for 1, 3, 7, 11, 15, and 20 days. The pH of both immersion chilled meats and vacuum packed meats were higher than those of their counterparts(P<0.05). The pH of atmosphere packed meats increased as the storage period extended. The moisture contents of vacuum packed meats were remarkably higher than those of atmosphere packed meats. The pH of all treatments decreased as the storage period extended. The shear values of air spray chilled and vacuum packed breast meats were significantly higher than immersion chilled and vacuum packed ones. However, immersion chilled and atmosphere packed breast meats were significantly higher than those of air spray chilled and atmosphere packed breast meats. The shear values of immersion chilled and vacuum packed thigh meats were significantly higher than those of immersion chilled and vacuum packed thigh meats. In atmosphere packed thigh meats, air spray chilling method showed higher shear values than those of immersion chilled thigh meats. In thigh muscle, tenderness values tended to decrease as the storage period extended(P<0.05). Contents of water soluble proteins of vacuum packed and air spray chilled breast and thigh meats were higher than those of their counterparts as the storage period extended(P<0.05). The contents of water soluble proteins significantly decreased as the storage period extended. Salt soluble proteins of atmosphere packed breast and thigh meats were remarkably higher than those of vacuum packed ones(P<0.05). Total lipid contents of atmosphere packed and air spray chilled breast and thigh meats were higher than those of atmosphere packed and immersion chilled meats as the storage period extended. The vacuum packed meats were significantly higher in total lipid contents than those of atmosphere packed meats. The storage period decreased the total lipid contents of cold chicken, Major fatty acids in cold-stored chicken were oleic, palmitic, linoleic and stearic acids, regardless of chilling method. Unsaturated fatty acids of all treatments decreased, but saturated fatty acids increased as the storage period extended.

• 한국축산식품학회지
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• 제18권3호
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• pp.240-247
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• 1998

This experiment was carried out investigate changes in proximate composition, pH, volatile basic nitrogen (VBN), thiobarbituric acid value (TBA) and mineral contents of pure Kaesojoo (PK) and Kaesojoo added medicinal herbs (KMH) during storage period (30 days) at 4$^{\circ}C$ and -18$^{\circ}C$. Two dogs with 12kg live weight were slaughtered to obtain samples from extracts. The results obtained were as follows: Crude fat and ash of KMH were higher than those of the PK, but the moisture and crude protein was higher in the PK (p＜0.001). Proximate composition did not affect cold and frozen storage and storage period. the pH of the PK through all periods. The VBN value of all treatment gradually increased during storage period. That of KMH tend to be lower than PK, all treatment was maintained freshness. The TBA value of all treatment gradually increased during storage period (p＜0.05). Cold storage and PK tend to be higher frozen storage and KMH. Among minerals Ca, K, Mg, Na, P contents of the KMH were higher than those of the PK and the Ca, Mg, Zn contents were significantly changes (p＜0.05) according to the storage period and temperature.

• 원예과학기술지
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• 제19권2호
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• pp.145-148
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• 2001

감귤의 품질에 미치는 CA 저장의 효과를 알아보기 위하여 본 실험을 수행하였다. 1998년 11월 제주도에서 수확된 온주밀감을 공시재료로 사용하였다. 무게감량과 경도는 저온저장구보다 CA 처리에서 저장기간 동안 높게 유지되었고 SSC 값은 저온저장 2개월까지 뚜렷이 증가하다가 그 이후 급격하게 감소한 반면 CA 처리에서는 저장 4개월까지 지속적으로 증가하는 양상을 나타내었다. 유기산은 CA 처리에서 저온저장에서 보다 약간 높게 유지되는 형태로 저장 중 모든 처리에서 크게 감소하였다. 시장성 판정을 위한 품질평가 결과에서도 CA 조건이 저온저장에 비하여 품질유지에 비교적 효과적이었다.

• 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.

• 한국양식학회지
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• 제10권4호
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• pp.381-386
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• 1997

A series of experiments were conducted to compare the effects of various diluents in cold storage on the marbled sole, Limanda yokohamae sperm. Various diluents of glucose, L. yokohamae serum, marine fish Ringer's solution, sodium citrate and Ca2+ free artificial seawater (ASM) (tris-HCI, pH 7.4) containing 3 mM ethylene glycol-bis (2-aminoethyl ether) tetraacetic acid (EGTA) were used to store the sperm at 4℃. The storage effect was evaluated using motility index and survival rate of sperm. Glucose and sodium citrate were found to be better diluents which maintained high motility and survival rate of sperm for a storage period of 10 days. Some morphological changes of spermatozoa were observed during the cold storage with diluents. In particular, a detachment of the nuclear enveloped and of the plasma membrane from the nucleus in spermatozoa was observed. Morphological normality of the stored spermatozoa diluted with 0.3 M glucose was better than that of the stored spermatozoa undiluted or diluted with Ca2+ free ASW containing 3 mM EGTA.

• 한국작물학회지
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• 제53권1호
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• pp.21-27
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• 2008

원료콩의 저장방법이 콩나물 생산수율에 영향을 미친다. 본 연구는 원료콩의 저장 기간과 방법이 발아 정도, 콩나물의 형태 및 생장에 미치는 영향을 조사하여 원료콩의 저장에 대한 정보를 제공하고자 채종당년 및 2년차의 이월 종자를 실온과 저온저장고에 계속 저장하거나 실온에 저장된 종자를 5월 1일부터 8월 31일까지 저온에 저장한 후 재배시험을 실시한 결과를 요약하면 다음과 같다. 1. 계속 저온 저장된 종자중에서 채종당해년도 종자는 이월종자에 비하여 상품성이 가장 좋은 하배축 길이가 7 cm 이상의 비율이 높았던 반면, 하배축 길이가$4{\sim}7\;cm$의 비율, 비정상개체 및 미발아 종자의 비율은 낮았다. 2. 계속 저온 저장된 종자중에서 채종당해년도 종자는 이월종자에 비하여 뿌리와 전체 길이, 하배축 생체중이 많았으나 전체 생체중은 차이가 없어 종자의 저장기간간에 따른 차이는 적었다. 3. 상품성이 가장 좋은 하배축 길이가 7 cm 이상인 비율은 채종당해년도 종자의 경우 실온에 저장하다가 5월 1일 저온 저장한 종자와 계속 저온 저장한 종자에서 상대적으로 높았던 반면, 이월종자는 실온에 저장하다가 5월 1일 저온저장한 종자와 계속 실온에서 저장한 종자에서 상대적으로 낮았다. 4. 세근형성율과 개체당 세근수는 채종당해년도 종자를 계속 저온 저장할 경우 콩나물의 생장 촉진으로 인하여 높고 많았다. 5. 하배축과 뿌리 길이, 하배축 직경, 생체중과 건물중은 계속 저온 저장할 경우 가장 길고, 굵고 많았으며, 실온에 저장하다가 저온으로 전환하여 저장시킨 종자, 계속실온에서 저장한 종자 순으로 감소하였다.