• 한국농공학회논문집
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• 제53권3호
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• pp.59-64
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• 2011

The objective of the study is to develop life cycle inventory (LCI) database of dam, a major facility for irrigation water supply. The types of database developed are three out of nine dams according to the size of the wate r storage capacity: two kinds larger than 500,000 $m^3$ depending on gate for discharging (Type 1) and the other dam smaller than 500,000 $m^3$ (Type 2). According to the LCI analysis, type 1 larger than 500,000 $m^3$ storage capacity with gate has the lowest environment impact in the 6 impact categories. The impact of the type 1 accounts for 7~35 % of the type 2 for supplying irrigation water. Comparing with the environment impacts of water for other uses such as drinking and industrial water, the impacts of 1 $m^3$ irrigation water supply is 4~45 % of the one for industrial water supply and 1~16 % of the drinking water's. The three types of LCI DB on the irrigation water by dams will be useful in the application of Life Cycle Assessment in agricultural products and environmental labelling including carbon footprint since it is complied to the guidelines of LCI DB constr uction issued by Ministry of Environment and Ministry of Knowledge Economy.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2009년도 춘계학술발표대회 논문집
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• pp.296-301
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• 2009

The ice storage system uses water for low temperature latent heat storage. However, a refrigerator capacity is increased and COP is decreased due to supercooling of water in the course of phase change from solid to liquid. This study investigates the cooling characteristics of the TMA-water clathrate compound including TMA (Tri-methyl-amine, $(CH_3)_3N)$ of $20{\sim}25wt%$ as a low temperature latent heat storage material. The results showed that the phase change temperature and the specific heat is increased and the supercooling degree is decreased as the weight concentration of TMA increased. Especially, the clathrate compound containing TMA 25wt% has the average phase change temperature of $5.8^{\circ}C$, the supercooling degree of $8.0^{\circ}C$ and the specific heat of 3.499 kJ/kgK in the cooling process. This can lead to reduction of operation time of refrigerator in low temperature latent heat storage system and efficiency improvement of refrigerator COP and overall system. Therefore, energy saving and improvement of utilization efficiency are expected.

• 물과 미래
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• 제28권6호
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• pp.217-228
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• 1995

홍수기중 최적의 저수지운영을 위해 서로 상반되는 이수와 치수를 조화시키기 위한 전반적이고 체계적인 운영방안을 제안하였다. 본 연구는 비홍수기의 용수수요 보장을 고려히 홍수기중 저수지의 제한수위를 결정하기 위한 것이다. 단기간별요 가변제한수위(VRWL)와 최소 확보저수위 (MRWL)를 적용하여 저수용량의 재할당으로 최적 운영방안이 유도되었다. 또한 갈수빈도해석에 따른 저수지운영분석으로 비홍수기의 용수공급을 위해 확보되어야 할 홍수기말 저수지의 수위조건에 관하여 대청과 충주 다목적댐을 대상으로 적용하고 그 결과를 분석하였다.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2006년도 하계학술발표대회 논문집
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• pp.1125-1130
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• 2006

An air source heat pump system producing the ice and water storage energy for cooling and heating of building has been proposed. Cycle design and simulation considering energy balance between heating and cooling capacity has been carried out. The roles of the capacity controlled compressor, refrigerant heating device and air preheating are investigated in detail. System control logic for meeting the predetermined heating capacity when the system is operated at cold climate condition is suggested. Some anticipated problems of the proposed system are also described.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2005년도 학술발표논문집
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• pp.260-265
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• 2005

The purpose of this study is to established a storage management method and operation standard for irrigation dams occupying the largest portion of small dams using storage management system. The system can be applied to seongju dam for effective management. The storage management method was established considering hydrology simulation and statistical analysis using the system. This method and operation standard are capable of analyzing additional available water, considering the water demand and supply of basin actually. It can improve the flood control capacity and water utilization efficiency by the flexible operation of storage space.

• Journal of Advanced Marine Engineering and Technology
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• 제26권2호
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• pp.240-247
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• 2002

Recently, a thermal energy storage system has been developed actively fur the purpose of saving energy and reducing the peak electrical demand. Especially, ice slurry is a promising working fluid for low temperature energy storage systems. A flow of ice crystals has a large cooling capacity as a result of the involvement of latent heat. However, there are still problems related to the recrystallization of ice crystals for realizing long term storage and long distance transportation. To find improvements fur this, a method for the creation of ice crystals resistant to recrystallization has been proposed and researched by the use of an antifreeze protein (AFP) solution etc. In the present study, it has been investigated the growth of ice crystal in several kinds of water solution added non-ionic surfactant. The results shows that size of ice crystal was smaller with increasing in added surfactant. And ice crystal was not increased with added surfactant.

• 한국수산과학회지
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• 제53권3호
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• pp.290-296
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• 2020

We investigated the effect of the modified starch [physical treatment, acetate (SA-1, SA-2, and SA-3), hydroxypropyl (HS), and acetylated distarch adipate] content on the physicochemical properties of fish cakes, called Eomuk in Korea, during storage at -20℃. When wheat flour (native starch, NS) was used, the moisture content decreased during frozen storage, resulting in a lower water-holding capacity and higher expressible drip. Compared with NS, adding modified starch had a lower effect on the moisture content during frozen storage. The water-holding capacity and expressible drip differed with the type of modified starch added. The expressible drip was lowest with HS; the SA-3 and HS modified starch were whiter than NS. Therefore, HS and SA-1 are suitable additives to improve the quality of frozen fish cakes.

• 동아시아식생활학회지
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• 제22권1호
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• pp.75-87
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• 2012

We investigated the physicochemical properties, pasting characteristics on the rapid visco analyzer, dough characteristics on a mixograph, product characteristics, and attributes of color and hardness of products made from a wheat bagel premix and rice bagel premix according to storage period and temperature. The pH and moisture content of stored rice bagel premix and wheat bagel premix, significantly decreased, depending on the storage temperature and time. The average of water retention capacity, alkaline water retention capacity, sedimentation value, and pelshenke value all significantly decreased temperature increases and increasing storage time. he initial pasting temperature and breakdown depending on the storage temperature and time showed a significant difference, but peak viscosity and setback with increasing storage time and temperature were not significantly different. The initial pasting temperature did not significantly affect the rice bagel premix. The midline peak time and band at 8 min of mixing time of the wheat bagel premix and rice bagel premix did not differ significantly. In product attributes, the cost of wheat bagel premix rice bagel premix and the L, a, and b value in color of wheat bagel premix showed significant difference. The hardness of wheat bagel premix according to storage time and the hardness of rice bagel premix depending on storage temperature significant difference. Therefore, storage time and temperature of wheat bagel premix and rice bagel premix and does not show significant differences. merchant can get regular and consistent, it is expected to lead to the promotion of rice consumption. Futhermore, research on better method to improve it's characteristics instead of wheat bagel premix is expected to.

• 한국농공학회지
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• 제31권2호
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• pp.116-124
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• 1989

Based on the theory of runoff equation proposed by SCS, the actual storage capacity(Sa) as a modified retention paramater was introduced to estimate the effective rainfall for the daily streamfiow analysis. During a storm, the actual storage capacity is limited by either soil water storage or infiltration rate as precipitation increases. Therefore, it was assumed that Sa is dependent on the baseflow before storm runoff(Qb) corresponding to soil water storage and the total amount of precipitation(P) corresponding to infiltration rate of a watershed. Effective rainfalls (Direct run-offs) estimate4 from SCS equation using Sa were compared with observed effective rainfalls at 10 watersheds in Geum river watershed boundary. 1. Regression equation for Sa was supposed Sa=Co+C$_1$XP+C$_2$X Qb Regression coefficients were highly significant at the level of 0. 01 and R$^2$ were 0.57 to 0.73. 2. The adjustment of coefficient of initial abstraction was made according to the storm size. It was adjusted to 025 for 30mm or less, 0.23 for 30 to 80mm, 0.20 for 80 to 200mm, and 0.1 for 200mm or more. 3. Regression equations between estimated and observed effective rainfall showed that slopes were 0.857 to 1.029 and R$^2$ were 0.779 to 0.989,

• 산업식품공학
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• 제15권4호
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• pp.311-317
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• 2011

활성글루텐이 첨가된 쌀 식빵 프리믹스를 5, 25, $35^{\circ}C$의 저장온도에서 4개월 동안 저장하면서 이화학적, 반죽특성, 호화특성 및 제빵특성에 미치는 영향에 대하여 조사하였다. 쌀 식빵 제조 시 활성글루텐의 적정 첨가량은 14-17%로 판단되었다. 쌀 식빵 프리믹스의 pH, 침전가 및 Pelshenke값은 저장기간이 증가함에 따라서 감소하는 경향을 보였으며, 특히 Pelshenke 값은 35$^{\circ}C$ 저장시에 그 수치가 현저히 감소하였다. 쌀 식빵 프리믹스의 수분 함량은 변화가 적었으나, 보수력과 알칼리수 흡수율은 저장온도가 상승함에 따라서 증가하는 경향을 보였다. Mixograph의 peak time과 width at 8.00 min은 저장온도가 상승함에 따라서 유의적으로 증가하는 현상을 보였다. Rapid Visco Analyser에 의한 호화 특성 중 peak viscosity와 setback은 저장 온도가 상승함에 따라서 다소 증가하는 현상을 보였으며, 저장기간이 길어짐으로써 유의적으로 증가하였다. 프리믹스로 제조한 쌀 식빵의 비용적은 저장전에 비해 저장 중 온도가 높아짐에 따라서 그 감소 폭이 컸으며, 쌀 식빵의 경도는 증가하여 쌀가루 전분의 노화가 밀가루에 비해 보다 빠른 속도로 진행되는 것으로 나타났다.