• Title/Summary/Keyword: storage period

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Design of Controllers for Battery Energy Storage System (2차전지 전력저장시스템의 제어기 설계)

  • 한석우;전윤석;최규하;목형수
    • Proceedings of the KIPE Conference
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    • 1999.07a
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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.

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Quality Characteristics of Sulgidduk added with Rubus coreanum Miquel during Storage (복분자 첨가 설기떡의 저장 중 품질 특성)

  • Cho Eun-Ja;Yang Mi-Ok;Hwang Chi-Hui;Kim Woon-Jin;Kim Min-Jeong;Lee Mi-Kyung
    • Journal of the East Asian Society of Dietary Life
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    • v.16 no.4
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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.

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Response of germination rate and seed moisture contents to storage temperature and frequency of seed banking on seed soybean (Glycine max) for storage period

  • Na, Young-wang;Lee, Young-yi;Yi, Jung-yoon;Son, Eun-ho;Park, Hong-jae
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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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.

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The Changes of Capsaicinoids and AST A Color Value of Red Pepper Powder Packed with Different Packaging Materials (포장재를 달리한 고춧가루의 저장조건에 따른 capsaicinoids와 색상 함량 변화)

  • 이선미;박재복;김선아;황인경
    • Korean journal of food and cookery science
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    • v.19 no.4
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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.

A Study on the Storage and Quality Characteristics of Duteoptteok Added with Mugwort (쑥을 첨가한 두텁떡의 저장성과 품질특성에 관한 연구)

  • Jung, Sook-Hee;Ahn, Hyung-Ki;Lee, Kyeoung-Im
    • Culinary science and hospitality research
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    • v.18 no.5
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    • pp.220-232
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    • 2012
  • The study was carried out to evaluate the storage and quality characteristics of Duteoptteok added with mugwort. The content of moisture and crude fiber in Duteoptteok significantly increased while that of the crude protein and crude ash decreased by adding 10, 20 and 30% of mugwort. As for the color value, the L, a, b value of Duteoptteok decreased as the amount of mugwort increased. Also, the L value decreased by the increase of the storage period. However, the a and b value didn't show any significant difference. For the texture characteristics, as the amount of mugwort increased, the hardness, springiness, cohesiveness, gumminess and chewiness decreased; however, the adhesiveness increased. Moreover, the hardness, adhesiveness, gumminess and chewiness increased according to the changes of the storage period, while the springiness and cohesiveness decreased. According to higher amount of mugwort, the gelatinization degree increased while the retrogradation degree decreased. The viable cell count and yeast and mold count showed a decreasing tendency as the amount of mugwort increased while they increased by increasing the storage period. The results from this study suggests that the quality characteristics of Duteoptteok improved and storage period became longer by adding mugwort.

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Physico-Chemical and Microbiological Changes during Storage of Fresh Ginseng (수삼저장중 이화학적 및 기생물학적 변화)

  • 오훈일;노해원;도재호;김상달;홍순근
    • Journal of Ginseng Research
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    • v.5 no.2
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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.

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A Study on the Heat-Storage/-Release Characteristics of a Regenerative Heat Exchanger Utilizing the Reversible Thermochemical Reaction of $Ca(OH)_2/CaO$ ($Ca(OH)_2/CaO$ 계의 가역 열화학 반응열을 이용한 축열식 열교환기의 축열 및 방열특성에 관한 연구)

  • Lee, Soo-Kag;Kim, Hong-Jea;Lee, Jin-Kook
    • Solar Energy
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    • v.9 no.2
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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.

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The Effects of Breed, Laying Age and Egg Storage Period on the Hatchability of Korean Native Chickens (한국토종닭의 품종, 산란 연령 및 종란의 보관 기간이 부화 능력에 미치는 영향)

  • Choi, Eun Sik;Sohn, Sea Hwan
    • Korean Journal of Poultry Science
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    • v.47 no.4
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    • pp.237-245
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    • 2020
  • This study investigated the effects of breed, laying age, and egg storage period on hatching performance. Eggs were collected from early laying period (27 to 29 weeks old) and late laying period (50 to 52 weeks old) in Hwanggalsaek Jaeraejong, Korean Rhode Island Red, and Korean White Leghorn chicken breeds. Eggs laid for each period were stored for 3, 7 and 14 days and then hatched. Fertility, hatchability, and embryonic mortality were observed to determine the hatching performance. The results showed that hatching performance was affected by breed, laying age, and egg storage period with independently or interactively. The Korean Rhode Island Red breed had the lowest hatching performance. Hatchability and early embryonic mortality rate increased in early laying period eggs compared to the late laying period, but the late embryonic mortality rate increased in late laying period eggs. Additionally, hatching performance decreased as the egg storage period increased. Using breed-specific hatching management techniques, avoiding late laying period eggs, and shortening the egg storage period to seven days after laying may improve the hatching performance.

Effect of Steaming Pressure and Time and Storage Period on Quality Characteristics of Baeksulgi (백설기 제조에서 찌는 압력과 시간 및 저장 기간에 따른 품질 특성)

  • Park Ji-Yang;Ryu Gi-Hyung
    • Food Science and Preservation
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    • v.13 no.2
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    • pp.174-179
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    • 2006
  • The objective of the study was to investigate the effect of steaming pressure (0.5, 1.0, and 1.5 bar), steaming time (5, 10, and 15 min), and storage period on Hardness, hardness rate constant and sensory characteristics of Baeksulgi prepared with optimum formula (rice new 100%, water 60%, salt 1.5%, and sugar 15%). Although the hardness was slowly increased during storage period from 0 hr to 8 hr and sharply increased after 12 hr of storage in case of 0.5 bay steam pressure, it was slowly increased after 12 hr storage time in case of steaming pressure at 1.0 ban Hardness rate constant of Baeksulgi was $0.217{\sim}0.184hr^{-1}$ at range of steaming time for $8{\sim}10$ min and pressure at $0.8{\sim}1.0$ bar which was relatively low. Hardness and elasticity of sensory evaluation were increased with the increases in steaming pressure, steaming time, and storage period but cohesiveness was decreased The highest overall preference was steaming pressure at 10 bar, steaming time for 10 min, and storage period for 12 hr. In conclusion, steaming pressure, steaming tim, and storage period influenced Baeksulgi quality such as hardness and sensory characteristics.

Evaluation of Stability in a Combined Extract of Paeoniae Radix and Glycyrrhizae Radix(EGHB010) as a Health Functional Food (건강기능식품 원료로서 작약감초복합추출물(EGHB010)의 안정성 평가)

  • Lee, Ki Man;Kim, Hyun Jong
    • Korean Journal of Pharmacognosy
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    • v.50 no.4
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    • pp.318-323
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    • 2019
  • This study was designed to establish the stability of EGHB010, a combined hot water extract of Paeoniae Radix and Glycyrrhizae Radix. Test of coliform groups, sensory evaluations, contents of moisture, and the amount of paeoniflorin and glycyrrhizin were determined during storage at 4, 25 and 35℃ for 6 months. Coliform groups were not observed and moisture contents were maintained about 3.0% during the storage period. Sensory characteristics including color, taste, texture and appearance were tested over 3 points throughout the entire storage period. It maintained the commercial value during the storage period. Contents of paeoniflorin and glycyrrhizin as indicator components were remained stably for the storage period. The shelf-life of EGHB010 based on a linear response to zero of sensory evaluation with the highest correlation coefficient was predicted. Finally, the shelf-life of EGHB010 was expected for about 3 years to consider in safety coefficient. The shelf-life data of EGHB010 can be used to develop a functional health ingredient.