• 한국가금학회지
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• 제43권1호
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• pp.31-38
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• 2016

Consumers demand fresh and high-quality eggs. Egg quality may be represented by shell color, shell weight, egg weight, shell thickness, shell density, albumen height, yolk color, albumen pH and viscosity. Various factors such as strain, age of hen, storage temperature, humidity, the presence of $CO_2$ and storage time affect egg quality. Therefore, we investigated the effects of storage time and temperature on egg quality to define the freshness of Korean market eggs. A total of 1,800 eggs were used for this experiment and were separated into 45 treatments with 40 eggs in each. The treatments were consisted of 15 storage periods (2 d to 30 d) and 3 storage temperatures ($2^{\circ}C$, $12^{\circ}C$, $25^{\circ}C$). Each egg was weighed and broken, and the height of the thick albumen, Haugh units (HU), egg shell color and yolk color were measured by a QCM+system. We also observed the physiochemical properties of eggs such as yolk pH, albumen pH and albumen viscosity. The egg weight, shell weight, albumen height, HU and albumen viscosity significantly decreased with increasing storage time and temperature. However, the albumen and yolk pH significantly increased with increasing storage period and temperature. The interaction effects between the storage period and temperature were significant for shell weight, shell density, egg weight, albumen height, HU, yolk color, yolk pH, albumen pH and albumen viscosity. In the analysis of the correlation with egg quality, the storage temperature exhibited a higher correlation coefficient than the storage period. In conclusion, storage time and temperature are the major factors affecting egg quality, but the storage temperature is a more sensitive determinant of egg quality deterioration compared with the storage period.

• 한국연초학회지
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• 제23권1호
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• pp.19-30
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• 2001

This study was carried out to investigate the influences of environmental condition in storage room, moisture content and packing weight of leaf on the carbonization of processed flue-cured leaf tobacco, and find out a regression model able to pre-estimate the degree of carbonization. The influence of temperature and humidity in storage room on the carbonization was high,, while that of packing weight was relatively low, However, high moisture content and packing weight of leaf accelerated the carbonization under the high temperature and humidity condition. Thus the leaf tobacco under the condition of 4$0^{\circ}C$, 7$0^{\circ}C$ R.H. in storage room, 16% moisture content and 286 kg/box of packing weight could be carbonized within one month. The pH, total sugar content, lightness(L) and yellowness(b) of leaf were closely related to carbonization of leaf during storage. There were significant regression and yellowness of leaf. It is considered that the certification and/or pre-estimation of carbonization during storage may be possible by applying the regression equation.

• 한국식품저장유통학회지
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• 제5권2호
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• pp.105-110
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• 1998

To find out suitable storage and marketing condition, northern type 'seosan' garlic was stored for 3 months at controlled atmosphere(CA), modified atmosphere(MA), low(0~1$^{\circ}C$) and room temperature(20$\pm$5$^{\circ}C$), and then marketed at low(2~3$^{\circ}C$) and room temperature (20$\pm$5$^{\circ}C$)after storage. The physiological properties of garlic were investigated among treatments. The garlic respiration increased after 2 months at room temperature storage, which seem to be dormancy break time. During storage of garlic by CA, MA condition, sprouting and weight loss were prevented effectively by suppress of respiration, and hardness was maintained higher then those of the others. Decay rate occurred 8.1% at room temperature storage, 2% at MA storage but didn't occurred at CA and low temperature storages. When marketed at room and low temperature after storage, increment of respiration and sprouting were delayed, and changes of weight and hardness were low in garlics stored at CA and MA. Decay rate occurred high in garlics stored at MA and room temperature.

• Nuclear Engineering and Technology
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• 제50권2호
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• pp.306-312
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• 2018

There is an increasing need in the United States and around the world to move used nuclear fuel from wet storage in fuel pools to dry storage in casks stored at independent spent fuel storage installations or interim storage sites. Under normal conditions, the Nuclear Regulatory Commission limits cladding temperature to $400^{\circ}C$ for high-burnup (>45 GWd/mtU) fuel, with higher temperatures allowed for low-burnup fuel. An analysis was conducted with FRAPCON-4.0 on three modern fuel designs with three representative used nuclear fuel storage temperature profiles that peaked at $400^{\circ}C$. Results were representative of the majority of US light water reactor fuel. They conservatively showed that hoop stress remains below 90 MPa at the licensing temperature limit. Results also show that the limiting case for hoop stress may not be at the highest rod internal pressure in all cases but will be related to the axial temperature and oxidation profiles of the rods at the end of life and in storage.

• 한국식품저장유통학회지
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• 제8권3호
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• pp.246-251
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• 2001

'창방조생 ' 과 '미백' 복숭아의 저장기간중 중량감모율은 상온무포장에서 4일후 각각 6.8%, 4.9% 이었으나 저온 (0~2$^{\circ}C$), 고습(95$\pm$3%) 조건에서 PE 무천공필름 포장저장구는 25일째 모두 1% 이내였다. 복숭아 저장중 경도변화는 상온에 비해 저온저장에서는 모두 큰 차이가 없었다. 두 품종 모두 저장기간중의 유기산과 가용성 고형분은 큰 차이를 나타내지 않았다. '칭방조생'과 '미백' 의 fructose, glucose 함량은 두 품종 모두 지장전보다 약간씩 증가였으나 Sucruse 함량은 25일 이후 감소하는 경향이었다. 복숭아는 30$\mu\textrm{m}$ LDPE fim 또는 25$\mu\textrm{m}$ SM60 film으로 포장하여 저온(0~2$^{\circ}C$), 고습(95$\pm$3%) 조건에서 저장할 경우 '창방조생'은 20일, '미백'은 25일까지 저장 가능하였다.

• 조명전기설비학회논문지
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• 제29권4호
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• pp.1-10
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• 2015

The light emitting diodes(LED) package of new structure is proposed to promote the reliability and lifespan by maximize heat dissipation occurred on the chip. We designed and fabricated the LED packages mixing the advantages of chip on board(COB) based on conventional metal printed circuit board(PCB) and the merits of Si sub-mount using base as a substrate. The proposed LED package samples were selected for the superior efficiency of the material through the sealant properties, chip characteristics, and phosphor properties evaluations. Reliability test was conducted the thermal shock test and flux rate according to the usage time at room temperature, high-temperature operation, high-temperature operation, high-temperature storage, low-temperature storage, high-temperature and high-humidity storage. Reliability test result, the average flux rate was maintained at 97.04% for each items. Thus, the Si sub-mount based LED package is expected to be applicable to high power down-light type LED light sources.

• Applied Biological Chemistry
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• 제48권2호
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• pp.140-149
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• 2005

청국장 제품의 저장조건 및 유통기간 중에 상품성의 변화를 조사하기 위하여 살균온도, 저장온도 및 저장기간별로 관능적 특성과 색도의 변화를 측정하여 SAS program의 반응표면분석법으로 monitoring하였다. 진공 포장한 청국장의 명도(L)값은 살균온도, 저장기간 및 저장온도 모두 1% 이내에서 유의확률을 가지는 것으로 나타나 세 조건 모두가 명도에 영향성이 높은 것으로 나타났다. 적색도(a)값은 진공포장의 경우 살균온도와 저장온도가 높을수록 증가하며 각기 독립적으로 영향을 미치는 것으로 나타났다. 일반포장의 경우, 저장온도가 높을수록 유의적 값(10% 이내)이 영향을 미치는 것으로 나타났다. 황색도(b)값은 진공 포장한 경우, 저장기간과 저장온도는 1% 이내에서, 살균온도의 경우 5% 이내에서 유의확률을 가지는 것으로 나타났다. 또한 두 포장군 모두 정상점이 안장점의 형태로 나타났다. 관능적 평가 중 외관에 대한 적합성은 두 포장군 모두 저장온도가 1% 이내의 유의확률로 결정적인 영향을 주었고, 냄새에 대한 적합성은 진공포장의 경우 살균온도가 10% 이내의 유의확률로서 관련성이 있었으나, 일반포장은 저장기간이 1% 이내, 살균온도가 5% 이내 유의확률로서 영향성이 있는 것으로 나타났다. 맛에 대한 적합성에서는 진공포장한 경우 저장기간이 1% 이내의 높은 관련성이 있었고, 일반포장은 저장온도가 5% 이내의 유의확률로서 관련성이 있었다. 관능검사의 전체적인 평가에서는 진공포장의 경우 살균온도가 $61.92^{\circ}C$, 저장 온도 $6.79^{\circ}C$, 저장기간 56.48일에서 5.15로 최대 값을 나타내었다.

• Journal of Biosystems Engineering
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• 제39권4호
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• pp.336-344
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• 2014

Purpose: In this study, the effect of milling on paddy rice stored at low temperature, the changes in grain temperature of bulk storage bags exposed at room temperature, the post-milling water content of paddy rice, the whiteness of rice, and the rate of pest incidence were investigated and data were analyzed. Methods: Changes in temperature inside the bulk storage bags kept at low temperature and grain temperature after exposure to room temperature were measured. Experiments were conducted for identifying the reasons of post-milling quality changes in paddy rice stored at low temperature. Results: It was determined that a short-term increase of water content in paddy rice was directly related to surface condensation, and that rice should be milled at least 72 h after removal from low-temperature storage, in order to completely eliminate surface condensation of paddy rice kept in bulk storage bags. It was observed that post-milling quality of rice changed, but water content was maintained at high levels for more than 18 d in rice that was milled when condensation occurred, regardless of paper or vinyl packaging. Rice whiteness rapidly decreased in rice that was milled when condensation occurred, regardless of packaging, while rice that was milled 72 h or more after removal from low temperature storage did not show any significant changes in whiteness. No pest incidence was observed up to 12 d after removal from low temperature storage, regardless of packaging. Starting at 18 d, after removal from low temperature storage, rice that was milled when condensation occurred, was affected by pests, while 24 d after removal from low temperature storage, all portions of rice were affected by pests. Conclusions: Our results suggest that changes in post-milling quality of rice could be significantly reduced by exposing paddy rice to room temperature for at least 72 h before milling, in order to allow the increase of grain temperature and prevent surface condensation.

• 한국축산식품학회지
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• 제35권6호
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• pp.793-799
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• 2015

The market sales of premium ice cream have paralleled the growth in consumer desire for rich flavor and taste. Storage temperature is a major consideration in preserving the quality attributes of premium ice cream products for both the manufacturer and retailers during prolonged storage. We investigated the effect of storage temperature (−18℃, −30℃, −50℃, and −70℃) and storage times, up to 52 wk, on the quality attributes of premium ice cream. Quality attributes tested included ice crystal size, air cell size, melting resistance, and color. Ice crystal size increased from 40.3 µm to 100.1 µm after 52 wk of storage at −18℃. When ice cream samples were stored at −50℃ or −70℃, ice crystal size slightly increased from 40.3 µm to 57-58 µm. Initial air cell size increased from 37.1 µm to 87.7 µm after storage at −18℃ for 52 wk. However, for storage temperatures of −50℃ and −70℃, air cell size increased only slightly from 37.1 µm to 46-47 µm. Low storage temperature (−50℃ and −70℃) resulted in better melt resistance and minimized color changes in comparison to high temperature storage (−18℃ and −30℃). In our study, quality changes in premium ice cream were gradually minimized according to decrease in storage temperature up to−50℃. No significant beneficial effect of −70℃ storage was found in quality attributes. In the scope of our experiment, we recommend a storage temperature of −50℃ to preserve the quality attributes of premium ice cream.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.III
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• pp.676-683
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• 2000

For high quality storage of agricultural products, temperature, humidity and gas conditions in a storage house should be controlled properly. But most of the low temperature storage house is depending on temperature control. This study aimed to develop an automatic control system for low temperature storage house that can control storage conditions such as temperature, humidity and $CO_2$ gas concentration. The developed system alarms the user, by telephone or beeper, when abnormal condition has occurred. The farmer can also monitor the inside condition of warehouse in his residence, by Internet. From the results of the performance test, the temperature and relative humidity in the warehouse is controlled within the range of ${\pm}0.5^{circ}C$ and ${\pm}2%$, respectively.