• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집D
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• pp.286-291
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• 2001

This paper describes an optimal scheduling for ice slurry systems for energy cost saving. The optimization technique applied in the study is the dynamic programming method, for which the state variable is the storage in the ice storage tank and the control variable is the state of chiller's on-off switching. Though the costs during charge period is included in optimization by taking the average cost of ice per hour for slurry making, the time horizon for the simulation is limited building cooling period because accurate charge rate from the ice maker into the ice storage tank cannot be estimated during the charge period. In the operating simulation after optimizing procedure, energy consumption and operating cost for the optimal control are calculated and compared with them for a conventional control with one case of cooling load profile.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1999년도 전력전자학술대회 논문집
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• pp.431-434
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• 1999

This paper presents design of controllers for battery energy storage system. The proposed battery energy storage system can be controlled to operate in the power conditioning mode or the inverter mode. The operation of this mode further divided into three cases: (a) in the peak load period, the load power supplied from the utility is minimized as far as possible; (b) in the off-peak load period, the utility supplies power to the load and charges the battery bank with automatic charging control; (c) in the medium load period, to save battery energy the real power flow out of the battery energy storage system is minimized. Besides, in all cases, the proposed battery energy storage system also automatically compensates the harmonics, subharmonics and reactive power factor in the utility side are much improved. Simulation results are presented by the effectiveness of the proposed controllers for battery energy storge system.

• 동아시아식생활학회지
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• 제16권4호
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• pp.458-467
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• 2006

In order to develop a Bokbunja(Rubus coreanum Miquel) with natural & food applications, the effects of Bokbunja juice and wine on the physical, textural anti bacterial and sensory properties of sulgiduck were examined. Aw of Bokbunja sulgiduck(BS) decreased as storage time prolonged. Bokbunja juice sulgiduck(BJS) was higher than Bokbunja wine sulgiduck(BWS) in water activity. BJS and BWS showed low tendency in pH as additional level was high and storage time was prolonged. Hardness of the samples increased as the storage period increased, the samples exhibited a rapid increase after 24 hours of storage. BJS was lower significantly than those of none bokbunja after 6 hours of storage. Chewiness increased slowly to 12 hours. it appeared sudden decrease after 12 hours. Adhesiveness increase of the storage 24 hours it appeared. Springiness slowly reduced with the storage period, especially J4 was slowly reduced gumminess of the samples increased as the storage period. Cohesiveness increase of the slowly width for during the storage 12 hours, increase of the largest width was after save 12 hours. Color a and b values increased significantly, as storage time was prolonged. Total colony of all the BS increased. total colony of BWS decreased as additional level of Bokbunja wine. All the sensory characteristics indicated rapid decrease tendency after 12hr storage. BWS showed higher score than BJS in overall acceptability. BWS and BJS increased in color and flavor as additional level of juice and wine increased, while softness decreased as storage time was prolonged. BWS 3% showed highest score among all the BS through all storage time. BWS 3% was most excellent in sensory evaluation.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.288-288
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• 2017

The seeds of soybean (Glycine max) were treated with different storage temperature for this study. The seeds of 3 accessions of soybean varieties in aluminum foil pack were used as materials. Storage temperature applied were $-18^{\circ}C$ and room temperature and seed banking (input after 3 days from output) frequencies were every 1, 6, and 12 month respectively for 9 years of storage period. As results seed banking frequency no affected to germination rate and seed moisture contents at $-18^{\circ}C$ storage room for seeds of soybean after 9 years. Germination rate of soybean seeds was changed from 96.2 % to 95.6 % averagely after 9 years of freezing ($-18^{\circ}C$) storage period. There were no differences in decreasing rate by number of seed banking frequency in soybean seeds. On the other hand, at room temperature germination rate of soybean seeds was decreased from 96.2 % to 27.3 % after 9 years which was decreased sharply to 55 % of initial viability after 6 years. The average rate of annual decrease of germination rate in soybean seeds was 38 % of initial viability at room temperature. Initial moisture contents of soybean seeds were 7.3 % and changed to 7.1 % at $-18^{\circ}C$ while it changed from 7.4 % to 7.0 % at room temperature after 9 years of storage period.

• 한국식품조리과학회지
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• 제19권4호
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• pp.439-446
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• 2003

This study was performed to investigate the change in the chemical components of red pepper powder using different packaging materials and various storage conditions. Red pepper powders with 11 and 15% initial moisture content were packed with five different materials and stored at different temperatures (0, 20, and 30 C) for a one year period. Over the storage period, each combination was periodically sampled, and examined for composition changes. The five packaging materials were: linear low density polyethylene(LLDPE), nylon/LLDPE(Ny/LLDPE), saran coated ethylene vinyl acetate copolymer/linear low density polyethylene(B650), nylon/Tie/nylon/ethylene-vinyl alcohol copolymer/nylon/Tie/LLDPE(RDX-2787) and oriented polypropylene/alumimum/LLDPE(OPP/Al/LLDPE), and the three storage conditions were (28.3${\pm}$1.0)$^{\circ}C$ with (15.5${\pm}$2.8)% relative humidity, (18.6${\pm}$0.5)$^{\circ}C$ with (46.6${\pm}$4.9)% RH, and (0${\pm}$2)$^{\circ}C$ with (80${\pm}$10)% RH, respectively. The moisture contents of all samples changed according to the relative storage humidity, except those of the samples packed with OPP/Al/LLDPE, which remained constant throughout the storage period. The capsaicinoids content of the red pepper powder did not change significantly for 6 months, but gradually decreased after that until about 85% of the original amount remained at the final stage of storage. The ASTA color values of all samples decreased gradually throughout the storage period. The higher the storage temperature, the more severe the deterioration. The color deterioration seemed greatly related to the existence of oxygen, as the deterioration was especially severe in the samples packed with LLDPE and B650, where the oxygen transmission rate were highest among the five packaging materials.

• 한국조리학회지
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• 제18권5호
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• pp.220-232
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• 2012

본 연구는 두텁떡에 쑥을 첨가하여 저장성과 품질 특성을 평가한 것이다. 쑥 첨가량이 10, 20 및 30%로 증가될수록 두텁떡의 수분 함량과 조섬유 함량은 상당히 증가되었으며 조단백질과 조회분은 감소되었다. 색도는 쑥 첨가비율에 따라 L, a, b값이 감소되었다. 또한 저장기간의 증가에 따라 L값은 감소되었으며, a값과 b값은 유의적인 차이를 나타내지 않았다. Texture 특성은 쑥 첨가 비율이 증가됨에 따라 경도, 탄력성, 응집성, 검성, 씹힘성은 감소되었으나 부착성은 증가되었다. 또한 저장기간의 증가에 따라 경도, 부착성, 검성, 씹힘성은 증가되었지만, 탄력성과 응집성은 감소되었다. 호화도는 쑥 첨가비율이 늘어날수록 증가되었고, 노화도는 쑥 첨가비율의 증가에 따라 감소되었다. 쑥을 첨가한 두텁떡의 생균수, 효모와 곰팡이의 수는 쑥의 첨가비율이 증가됨에 따라 감소되었으며, 저장기간이 늘어남에 따라 증가되었다. 이상의 결과에서 두텁떡에 쑥을 첨가함으로써 품질이 개선되었고 저장기간이 증가된다는 것을 알 수 있었다.

• Journal of Ginseng Research
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• 제5권2호
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• pp.99-107
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• 1981

Physical, chemical and microbiological changes were periodically studied during six-month storage of fresh ginseng under N2, CO2 gas or subatmospheric pressure condition. The results were summarized as follows. 1. The moisture contents of fresh ginseng gradually decreased during the first 2-month storage and thereafter generally reached at equillibrium. 2. There was no significant change in the reducing sugar content in 1-month storage, followed by$.$a decrease in between 2-and 3-month storage. Thereafter, the reducing sugar content increased at the end of 4-month storage. 3. The total sugar content increased significantly during the first 3-month storage. Under CO2 and Nr gas storage, the total sugar content gradually decreased after 3-month storage, while no significant change was observed in the samples stored under subatmospheric Pressure. Amylase activity gradually decreased as storage period increased 4. The content of saponin decreased as storage period increased, but ginsengoide Rf, Rd, Rc and Rb2 increased significantly in 1-month storage. 5. Regardless of storage methods, sprouting of ginseng and growth of microorganisms were inhibited in all samples during the first 4-month storage. However, growth of microorganisms was observed in the rhizome and injured areas of ginseng after 5-month storage in the N2 and CO2 gas atmosphere.

• 태양에너지
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• 제9권2호
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• pp.22-30
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• 1989

Since the energy storage method by means of the thermochemical reaction has no heat loss by separating the reactants under the storage period, it is remarked as one of promising means particularly for long-term heat storage. In this study, the heat-storage/-release characteristics of the reversible chemical reaction cycle, $Ca(OH)_2/CaO$, is numerically analysed by a mathematical modelling. As a result, the effectiveness of the heat exchanger by the chemical heat storage method is considerably higher than that by the sensible heat storage method. It is found that the major parameters, which determines the effectiveness of the heat exchanger, are the mass flow rate and inlet temperature of fluid, the residence time, etc.. The heat-storage/-release period can be controlled by changing the operation conditions. It is expected that the results obtained here will supply useful informations in designing a regenerative heat exchanger utilizing the thermochemical reaction.

• 한국가금학회지
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• 제47권4호
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• pp.237-245
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• 2020

본 연구는 종계의 품종, 산란 연령 및 종란의 보관 기간이 부화 성적에 미치는 영향을 살펴보고 자 한 것으로 한국토종닭인 재래황갈종, 토착레그혼종 및 토착로드종이 산란한 종란을 대상으로 산란 초기인 27~29주령 때 수집한 종란과 산란 후기인 50~52주령에 산란한 종란을 각각 3일, 7일 및 14일 보관 후 부화를 진행하였다. 조사 항목으로는 수정률, 부화율 및 배자발육중지율을 조사하고, 각 요인별 부화 성적을 분석하였다. 분석 결과, 종계의 품종, 산란 연령 및 종란의 보관 기간이 독립적으로 혹은 복합적으로 부화 성적에 영향을 미치는 것으로 나타났다. 종계의 품종에 따른 비교에서 토착로드종의 부화 성적이 가장 저조하였는데, 특히 이들이 산란 초기에 생산한 종란에서 초기 배자 사망률이 현저히 높게 나타났다. 산란 연령에 따른 부화 성적은 산란 초기에 생산한 종란의 부화율이 산란 후기에 생산한 종란에 비해 높게 나타났는데, 초기 배자 사망률은 산란 초기의 종란에서, 후기 배자 사망률 및 사롱란의 비율은 산란 후기의 종란에서 상대적으로 높게 나타났다. 종란의 보관 기간에 따른 부화 성적은 거의 대부분의 조사 항목에서 종란의 보관 기간이 길어질수록 부화 성적은 저하되는 것으로 나타났다. 이상의 결과를 종합할 때, 우수한 부화 성적을 얻기 위해서는 품종에 따른 각기 다른 부화 관리가 필요하며, 산란 후기에 생산된 종란의 이용은 피하고 종란의 보관 기간은 7일 이내로 짧게 하는 것이 바람직할 것으로 사료된다.

• 한국식품저장유통학회지
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• 제13권2호
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• pp.174-179
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• 2006

백설기의 최적 배합비(쌀가루 100%, 수분 60%, 소금 1.5%, 설탕 15%)를 선정하여 찌는 압력(0.5, 1.0, 1.5 bar)과 찌는 시란(5, 10, 15분)을 달리하여 시료를 제조 후 저장기간(0, 4, 8, 12, 24시간)에 따른 백설기의 굳기변화와 굳기속도 및 관능적 특성의 결과를 살펴보았다. 굳기는 저장기간 0시간에서 8시간은 완만하게 증가하였지만 12시간 이후에는 급격하게 증가하는 경향을 나타내었지만 찌는 압력이 1.0 bar에서 10, 15분간 편 시료는 12시간 이후에도 완만하게 증가하였다. 한편 굳기속도상수는 찌는 시간 $8{\sim}10$분과 찌는 압력 $0.8{\sim}1.0bar$에서 상대적으로 낮은 $0.175{\sim}0.184hr^{-1}$의 값을 보여 최적 조건으로 판단되었다. 찌는 압력과 시간 및 저장기간이 증가할수록 견고성과 탄성은 증가하는 경향을 보였지만 응집성은 찌는 압력과 저장기간이 증가할 수록 감소하는 경향을 나타내었다. 전체적인 기호도는 찌는 압력 1.0 bar, 찌는 시간 10분에서 저장기간 12시간일 때 가장 높은 값을 보였다. 결론적으로 백설기의 저장기간과 함께 제조공정변수인 찌는 압력과 시간에 따라 굳기 및 굳기속도와 관능적 품질특성이 변화하였다.