• 한국식품저장유통학회지
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• 제16권3호
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• pp.327-332
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• 2009

관행, 저농약 및 유기농 재배한 참다래 과실의 저온저장 중 품질변화를 조사하였다. 경도는 저장초기 심하게 감소한 다음 연화되는 경향을 보였는데 연화 속도는 유기농 과실에서 다소 빨랐다. 당도는 저장 중 증가하는 경향을 보인 반면, 산함량은 감소하였고, pH는 변화가 없었다. 환원당 함량은 전분함량이 감소하면서 저장초기 크게 증가하는 경향을 보였다. 유기농 과실은 저장 중 부패율이 관행재배나 저 농약재배에 비해 유의하게 높았고, 병을 유기하는 병원균은 잿빛곰팡이, 연부병, 꼭지썩음병 순으로 높았다. 호흡량과 함께 에틸렌발생량이 증가하면서 과실이 연화되었는데, 호흡량과 에틸렌함량은 유기농 과실에서 다소 높은 경향을 나타내었다. 유기농 과실은 연화와 함께 부패과 증가로 관행재배나 저 농약재배에 비해 저장력이 감소되었다.

• Journal of Electrical Engineering and Technology
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• 제5권2호
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• pp.228-238
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• 2010

There is an increasing interest in research to help overcome the energy crisis that has been focused on energy storage applications in various parts of power systems. Energy storage systems are good at enhancing the reliability or improving the efficiency of a power system by creating a time gap between the generation and the consumption of power. As a contribution to the various applications of storage devices, this paper describes a novel algorithm that determines the power and storage capacity of selected energy storage devices in order to improve upon railroad system efficiency. The algorithm is also demonstrated by means of simulation studies for the Korean railroad lines now in service. A part of this novel algorithm includes the DC railroad powerflow algorithm that considers the mobility of railroad vehicles, which is necessary because the electric railroad system has a distinct distribution system where the location and power of vehicles are not fixed values. In order to derive a more accurate powerflow result, this algorithm has been designed to consider the rail voltage as well as the feeder voltage for calculating the vehicle voltage. By applying the resultant control scheme, the charging or discharging within a specific voltage boundary, energy savings and a substation voltage stabilization using storage devices are achieved at the same time.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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• pp.24-27
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• 1996

The storage function method(SFM) is one of hydrologic flood routings which has been used most widely in Korea and Japan. This paper presents a storage function method using multiple model adaptive estimation(MMAE), in which a model set is generated by partitioning storage parameters over feasible range, and each storage function model is estimated, and then the weighted average of them is calculated. Finally, the future runoff is predicted in real time by means of observed data of water level at dam and rainfall. Simulation results applied to actual data show that the proposed method has much better performance than that of conventional SFM.

• 대한토목학회논문집
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• 제33권3호
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• pp.927-935
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• 2013

본 연구에서는 서울대학교 댐 하류 노천강당 유역과 공대폭포 유역에 지속시간 1시간 50년 빈도 강우에 관한 저수지 홍수추적을 실시하고 지하저류조가 설치되는 경우 다음의 사항에 초점을 맞추어 분석을 수행하였다 (1) 저류조의 저류량; (2) 우수유출량 및 첨두수위의 저감정도; (3) 지체시간 변화; (4) 신설 지하저류조의 유출입부 암거 설계. 노천강당 유역에 $25,000m^3$ 저류조가 설치되는 경우 총 유입량 대비 49.43 %의 저류효과가 발생하고 49.64 %의 첨두 유량 감소효과와 28분의 지체시간 증대효과를 얻을 수 있었으며, 첨두 수위는 $15,000m^3$ 저류조에 비해 35 cm 낮게 나타났다. 기존 저류시설과 신설 지하저류조의 공동 운영을 통해, 홍수 발생 시 댐 유역에서 초과되는 유출량을 탄력적으로 관리할 수 있는 것으로 판단된다.

• 한국식품위생안전성학회지
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• 제11권3호
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• pp.189-196
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• 1996

Based on microbiological-chemical test results under simulated time-temperature conditions, total plate count, coliform, and volatile basic nitrogen were selected as effective quality indicators for estimating probable shelf-life on Kim Pab dosirak marketed in convenience stores, and shelf-life at each storage temperature was calculated from regression equation between effective quality indicator standard limit and storage time. Estimated shelf lives of Kim Pab Dosirak were 17, 3 and 2 hours respectively under 1$0^{\circ}C$, 2$0^{\circ}C$ and 3$0^{\circ}C$. Because shelf-life was especially affected by intial values, regression analysis between initial effective quality indicator values and storage hours was performed for the estimation of probable shelf-life on Kim Pab during storage at 10, 20, or 3$0^{\circ}C$.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2000년도 전력전자학술대회 논문집
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• pp.689-692
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• 2000

This paper presents a designing for the Off-line UPS usig SMB Flywheel Energy Storage System. This described flywheel energy storage system is designed to replace of the conventional EMB(Electro Mechanical Battery) system. To realize the high efficiency and to minimize the torque ripple the waveform of the inverter output current is controlled to be sinusoidal. The actual performance of the Off-line UPS using flywheel energy storage system is described. The prototype device was manufactured, The experimental result has good characteristics at a time of power transition region and regeneration modes,

• Asian-Australasian Journal of Animal Sciences
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• 제21권3호
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• pp.420-425
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• 2008

The storage of rice polishing (RP) with and without addition of antioxidant for sixteen weeks and its effect on rancidity and metabolizable energy values during the summer season was determined. Fifteen Single Comb White Leghorn cockerels of approximately uniform age and weight were procured and kept in metabolic cages under standard feeding and management practices. Five force feeding trials were conducted. In the first trial, fresh RP with 0 weeks of storage (diet 1 and 2) was used followed by four feeding trials with 4 (diet 3, 4), 8 (diet 5, 6), 12 (diet 7, 8), and 16 (diet 9, 10) weeks of storage of RP. The same birds were used in all trails. The birds were fasted for a period of 21 h, followed by force feeding of 20 g of RP with and without antioxidant for all storage periods. The control/fasting group was also maintained to measure endogenous fecal losses. Excreta were collected after 48 h for the determination of AME and TME values of RP. Along with the biological trials, laboratory assay of the RP stored with and without antioxidant was conducted to measure the extent of rancidity in terms of Thiobarbituric acid value (TBA). The TBA values were affected (p<0.05) by storage period and the values increased when the storage period increased from 4 to 16 weeks. However, the TBA values were significantly reduced (p<0.05) when RP was stored after addition of antioxidant when compared with the values obtained from RP stored without antioxidant (diet 3 vs. 4, 5 vs. 6, 7 vs. 8, and 9 vs. 10). The AME MJ/kg and TME MJ/kg values of RP were neither affected by increase in storage period nor addition of antioxidant. The findings of this study revealed that there was no effect of rancidity and storage time on the nutritive value, AME or TME of RP in poultry. However, TBA values were increased with the increase in storage period.

• 한국식품조리과학회지
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• 제27권1호
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• pp.63-73
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• 2011

Cabbage (Baechu) Kimchi in its truncated form was placed in four different packing materials, Ny/PE/LLDP, OPP/AL/PE, PP and PET, and quality changes were observed during storage. Changes in pH and total acidity showed an x-shaped cross-curve as pH decreased and total acidity increased during storage. PP tray showed the slowest change at $5^{\circ}C$ with time. The pH was initially 6.25, but decreased to 4.12~4.16 at 20 days, and total acidity showed a 4 to 4.8-fold increase after 20 days of storage compared to the initial value. During storage at $5^{\circ}C$, total bacterial count and lactic acid bacterial count rapidly increased after 4 days. The total bacterial quantity decreased after a period of time and there were differences according to packaging material; OPP/AL/PE packaging showed the most dramatic decrease. Change in microbial count mostly followed a similar pattern to that of total acidity for all packaging materials. Changes in the color of Kimchi liquid, when examined by color index in $L{\cdot}b$/a form, rapidly decreased over time, similar to pH. Small Ny/PE/PP and OPP/AL/PE packages of Kimchi were examined for changes in free volume inside the packaging. After 13 days of storage at $5^{\circ}C$, the volume was 243 mL, but storage at $20^{\circ}C$ resulted in a volume of 372 mL, a more than 1.5-fold increase in free volume. There were changes in the quality characteristics of small package Kimchi according to storage temperature and packaging material, and large changes in pH, total acidity, and microbial count were evident upon storage at $5^{\circ}C$ for 8 days, which was the optimum palatability period. Mostly, PP treatment showed the slowest quality changes upon storage at $5^{\circ}C$. However, due to small package Kimchi's fast consumption system, the appropriate choice of packaging material must consider the product's turnover ratio. Further, the varieties of small package Kimchi should be diversified according to different consumer preferences by offering Kimchi with different maturity levels. Further, since the leading consumer base ranges in age from the teens to thirties, the development of various products targeting such consumers is necessary.

• 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.

• 한국식품위생안전성학회지
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• 제12권2호
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• pp.107-110
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• 1997

To examine the effects of residual phosphorus content on color reversion and storage stability of corn germ oil, the changes of Lovibond total color and stability of oxidation were determined according to the different storage periods at room and incubating temperature, respectively. The residual phosphorus content and storage temperature had the synergistic effect on color reversion during short time storage. The extent of color change was the greatest when oils were stored for 1.0∼1.5 years at room temperature and thereafter gradually tended to reverse color reversion. It is supposed that the double bonds of carotenoids in oils were oxidized and then turned to the volatiles such as epoxide, ionone, and etc. In contrast, the residual phosphorus content increased oxidation stability of oils. The residual phosphorus content was closely correlated with the color reversion and storage stability, respectively.