• Title/Summary/Keyword: Storage term

Search Result 1,013, Processing Time 0.028 seconds

Potential of Initial CA Condition on Quality Maintenance of 'Fuji' Apples during Export Simulation after Long-term Storage

  • Park, Youn-Moon;Park, Hyo-Geun
    • Horticultural Science & Technology
    • /
    • v.30 no.4
    • /
    • pp.400-408
    • /
    • 2012
  • Effects of initial controlled atmosphere (CA) treatment on quality maintenance of 'Fuji' apples were assessed and compared with 1-methylcyclopropene (1-MCP) treatment and continuous CA storage. Apples were harvested twice at different maturity, treated with 1 ${\mu}L{\cdot}L^{-1}$ 1-MCP and then stored for 8 months at $0^{\circ}C$ under 3 conditions: air, CA for the first month followed by air (initial CA), and continuous CA (full CA). CA storage was performed with 1.5 kPa $O_2$ and < 1.0 kPa ($N_2$ balance). Following long-term storage, export simulation, refrigerated shipment and local distribution, were performed by holding apples at $0^{\circ}C$ for 2 weeks and on the shelf at $20^{\circ}C$ for 7 days. Both the application of 1-MCP and CA storage reduced ethylene production and respiration rates. Initial CA storage was also effective on reducing the metabolism although the effects were not as noticeable as full CA. Full CA storage with or without 1-MCP treatment maintained titratable acidity, flesh firmness, and sensory quality at the acceptable to excellent level even after the export simulation following 8-month storage regardless of harvest maturity. In contrast, effects of initial CA storage were limited to the maintenance of firmness and texture in early-harvested apples. Overall results indicated that harvest maturity is the critical factor for export fruit quality after long-term storage when separate treatment of initial CA storage or 1-MCP treatment is applied as a postharvest program.

Short-term Storage and Cryopreservation of Abalone (Haliotis discus hannai) Sperm

  • Kang, Kyoung-Ho;Kim, Jae-Min;Kim, Young-Hun
    • The Korean Journal of Malacology
    • /
    • v.20 no.1
    • /
    • pp.17-26
    • /
    • 2004
  • In present study, attempts were made to preserve abalone (Haliotis discus hannai) sperm in liquid form at low temperature, to evaluate the effect of various diluents in short-term storage on sperm, and cryopreservation procedures were optimized for the cryoprotectants and freezing rates, as well as the motility, survival rate, and the ultrastructural changes of sperm after short-term storage and cryopreservation were observed. The abalone sperm reached maximum motility until about 4 min after activation. The motility was constant for about 16 min, after which it dropped gradually, and about 50 min later all motility ceased. In Hanks' balanced salt solution (HBSS, 300 and 400 mOsmol/kg) and 150, 250 and 350 mOsmol/k artificial seawater (ASW), the sperm was immotile. After 100% ASW was added, motility of those sperm, which are in 300, 400 mOsmol/kg HBSS, 250, 350 mOsmol/kg ASW, could be again restored incompletely. Sperm motility can be maintained for 20 days of cold storage only in ASW of 850 and 1200 mOsmol/kg. A high motility index of 3.5-4.5 was observed for the first 8 days in 850 and 950 mOsmol/kg ASW. In other diluents sperm motility was constant less than 10 days, and the motility index was obviously lower than that of sperm in 850 and 1200 mOsmol/kg ASW. After 20 days of cold storage, survival rates of 10.2%-20.7% were obtained in ASW and 300 mOsmol/kg HBSS, and that in 400 HBSS (65.3%) was significantly higher than others. The constant period of sperm motility stored in 850 mOsmol/kg ASW was obviously longer than that in 1200 mOsmol/kg ASW after 6 days of storage. The sperm plunged into liquid nitrogen all died except that sperm using 15% glycerol as cryoprotectant restored 10.4% of motility. The highest motility index (3.4) was obtained with 5% glycerol and freezing procedure: $-50^{\circ}C$/min from $20^{\circ}C$ to $-80^{\circ}C$.

  • PDF

Studies on the Change of Components with Long-Term Storage of paddy (장기저장 미곡의 성분변화 특성)

  • 김영수
    • The Korean Journal of Food And Nutrition
    • /
    • v.12 no.4
    • /
    • pp.409-414
    • /
    • 1999
  • In order to investigate the changes of rice qualities during 4 years storage of paddy stored in ware-house of normal temperature condition. Temperature in warehouse was changed more than 3$0^{\circ}C$ under the influence of average temperature outside of a warehouse. Water content of paddy was not increased over 15% But as average temperature in warehouse was gone up 18$^{\circ}C$ from June to September every years it was supposed that these periods were to be deterioration of rice quality. On investigation of change in paddy it was supposed that these periods were to be deterioration of rice quality. On investigation of change in paddy components during the long term storage, reducing, sugar, amylose, crude protein were increased 0.24%, 19.23%, 7.02% at enterance time to 0.5%, 20.31% 7.46% 4 years later respectively. Max viscosity final visocity and set back value by amylograph were increased 449B,U 610B.U, 161B.U to 493B.U, 715B,U 222B.U but breakdown was decreased 125B.U to 76B.U with the increase of storage period. Gel consistency of rice stored was decreased 44.7mm at enterance time to 39,9mm 4years later. Fatty acid was increased remarkably 4.5KOHmg/100g to 24.4KOHmg/100g. Germination ratio and germ activity of paddy during long-term storage were decreased 97%, 100% to 0%, 0.4% respectively, With the increase of storage period contaminated paddy by molds increased and its by bacteria decreas-ed.

  • PDF

Parameter Optimization of Long and Short Term Runoff Models Using Genetic Algorithm (유전자 알고리즘을 이용한 장·단기 유출모형의 매개변수 최적화)

  • Kim, Sun-Joo;Jee, Yong-Geun;Kim, Phil-Shik
    • Journal of The Korean Society of Agricultural Engineers
    • /
    • v.46 no.5
    • /
    • pp.41-52
    • /
    • 2004
  • In this study, parameters of long and short term runoff model were optimized using genetic algorithm as a basic research for integrated water management in a watershed. In case of Korea where drought and flood occurr frequently, the integrated water management is necessary to minimize possible damage of drought and flood. Modified TANK model was optimized as a long term runoff model and storage-function model was optimized as a short term runoff model. Besides distinguished parameters were applied to modified TANK model for supplementing defect that the model estimates less runoff in the storm period. As a result of application, simulated long and short term runoff results showed 7% and 5% improvement compared with before optimized on the average. In case of modified TANK model using distinguished parameters, the simulated runoff after optimized showed more interrelationship than before optimized. Therefore, modified TANK model can be applied for the long term water balance as an integrated water management in a watershed. In case of storage-function model, simulated runoff in the storm period showed high interrelationship with observed one. These optimized models can be applied for the runoff analysis of watershed.

Bacteriological Characteristic of Atrina pectinata and Ruditapes philippinarum under Non-refrigerated and Refrigerated Storage Conditions

  • Kang, Kyoung-Ho;Kim, Byeong-Hak;Kim, Young-Hun
    • The Korean Journal of Malacology
    • /
    • v.24 no.1
    • /
    • pp.25-32
    • /
    • 2008
  • In order to estimate the necessity of refrigerated storage of fresh seafood for short-term storage, and evaluate the effect of refrigerated storage on pen shell Atrina pectinata and clam Ruditapes philippinarum collected from Jang-su of Deukryang Bay and I-mok of Sunchen Bay in South Korea, the counts of coliform, Escherichia coli and total aerobic bacteria in A. pectinata and R. philippinarum under non-refrigerated $(28{\pm}1^{\circ}C)$ and refrigerated storage conditions $(4{\pm}1^{\circ}C)$ were determined. The results indicated that the storage at temperature of $4^{\circ}C$ possessed significant effects on inhibiting bacterial growth in live seafood. And refrigerated storage had different effect on A. pectinata and R. philippinarum. Different species and culture environments significantly influenced the initial and ultima bacteria counts. This study confirmed that refrigerated storage for short-term storage of live seafood was necessary, and indicated that the effect of refrigerated storage was influenced by comprehensive effectors.

  • PDF

A Numerical Modelling of Cogeneration Systems for the Short-Term Operation Strategy (열병합발전시스템의 단기운전계획을 위한 수리적 모델 수립에 고나한 연구)

  • 류승헌;이종범;김준현
    • The Transactions of the Korean Institute of Electrical Engineers
    • /
    • v.43 no.5
    • /
    • pp.721-729
    • /
    • 1994
  • In this paper an optimization of the industrial congeneration system which have a thermal storage tank is proposed for the short-term operation strategy. Short-term operation costs of topping cycle and bottoming cycle are calculated by using the proosed model of a thermal storage tank. Simulation result of four cases are compared and analyzed each other.By these simulations which are similar to real operation circumstances. the validity of the proposed model is verified.

Application of two-term storage function method converted from kinematic wave method (운동파법의 변환에 의한 2항 저류함수법의 적용)

  • Kim, Chang Wan;Chegal, Sun Dong
    • Journal of Korea Water Resources Association
    • /
    • v.52 no.12
    • /
    • pp.1057-1066
    • /
    • 2019
  • The storage function method is used as a flood prediction model for four flood control offices in Korea as a method to analyze the actual rainfall-runoff relationship with non-linearity. It is essential to accurately estimate the parameters of the storage function method for accurate runoff analysis. However, the parameters of the storage function method currently in use are estimated by the empirical formula developed by the limited hydrological analysis in 2012; therefore, they are somewhat inaccurate. The kinematic wave method is a method based on physical variables of watershed and channel and is widely used for rainfall-runoff analysis. By adopting the two-term storage function method by the conversion of the kinematic wave method, parameters can be estimated based on physical variables, which can increase the accuracy of runoff calculation. In this research, the reproducibility of the kinematic wave method by the two-term storage function method was investigated. It is very easy to estimate the parameters because equivalent roughness, which is an important physical variable in watershed runoff, can be easily obtained by using land use and land cover, and the physical variable of channel runoff can be easily obtained from the basic river planning report or topographic map. In addition, this research examined the applicability of the two-term storage function method to runoff simulation of Naechon Stream, a tributary of the Hongcheon River in the Han River basin. As a result, it is considered that more accurate runoff calculation results could be obtained than the existing one-term storage function method. It is expected that the utilization of the storage function method can be increased because the parameters can be easily estimated using physical variables even in unmeasured watersheds and channels.

A STUDY ON THE INITIAL CHARACTERISTICS OF DOMESTIC SPENT NUCLEAR FUELS FOR LONG TERM DRY STORAGE

  • Kim, Juseong;Yoon, Hakkyu;Kook, Donghak;Kim, Yongsoo
    • Nuclear Engineering and Technology
    • /
    • v.45 no.3
    • /
    • pp.377-384
    • /
    • 2013
  • During the last three decades, South Korean nuclear power plants have discharged about 5,950 tons of spent fuel and the maximum burn-up reached 55 GWd/MTU in 2002. This study was performed to support the development of Korean dry spent fuel storage alternatives. First, we chose V5H-$17{\times}17$ and KSFA-$16{\times}16$ as representative domestic spent fuels, considering current accumulation and the future generation of the spent fuels. Examination reveals that their average burn-ups have already increased from 33 to 51 GWd/MTU and from 34.8 to 48.5 GWd/MTU, respectively. Evaluation of the fuel characteristics shows that at the average burn-up of 42 GWd/MTU, the oxide thickness, hydrogen content, and hoop stress ranged from $30{\sim}60{\mu}m$, 250 ~ 500 ppm, and 50 ~ 75 MPa, respectively. But when burn-up exceeds 55 GWd/MTU, those characteristics can increase up to 100 ${\mu}m$, 800 ppm, and 120 MPa, respectively, depending on the power history. These results demonstrate that most Korean spent nuclear fuels are expected to remain within safe bounds during long-term dry storage, however, the excessive hoop stress and hydrogen concentration may trigger the degradation of the spent fuel integrity early during the long-term dry storage in the case of high burn-up spent fuels exceeding 45 GWd/MTU.

Storability of Soybean Lines for Maintanance of Germplasm (대두유전자원의 안전보존을 위한 계통간 발아수명검정)

  • Kwon, S.H.;Han, Y.H.;Lee, Y.I.
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.29 no.3
    • /
    • pp.275-279
    • /
    • 1984
  • To develop a long term storage technique of soybean germplasm, fifty lines of soybean seeds were kept in storage room controlled by air-conditioner and dehumidifier at KAERI. The storage room was kept below 25$^{\circ}C$ of temperature and 60% relative humidity. Germinability of stored seeds was evaluated at every three or six months. On the other hand, the newly harvested seeds of the lines were accerelated aging at 40$^{\circ}C$ and 90% of relative humidity, and compared with non-accerelated seeds. The average germinability at the starting time of storage was 97% but the germinability was decreased to 62% at 42 months after storage in the storage room. The germinability seemed to be affected by seed size and seed coat color. The germinability of small seed lot tended to be higher than that of large seed lot, and the germination response in longer term of storage was greater than those of shorter term of storage. The accerelated aging test for 7 days proved to be a useful technique to pretest germinability of soybean seeds for assaying the relative storage potential.

  • PDF

iKSNF, the Control Tower for the R&D Program of SNF Storage and Disposal

  • Kim, Kyungsu
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
    • /
    • v.20 no.2
    • /
    • pp.255-258
    • /
    • 2022
  • Three government bodies, that is, the Ministry of Science and ICT (MSIT), Ministry of Trade, Industry, and Energy (MOTIE), and Nuclear Safety and Security (NSSC), jointly established the Institute for Korea Spent Nuclear Fuel (iKSNF) in December 2020 to secure the management technologies for spent nuclear fuel (SNF). The objective of iKSNF is to successfully conduct the long-term research and development program of the 「Development of Core Technologies to Ensure Safety of Spent Nuclear Fuel Storage and Disposal System」. Our program, known as the first multi-ministry program in the nuclear field of Korea, mainly focuses on developing core technologies required for the long-term management of SNF, including those for safe storage and deep geological disposal of SNF. The program comprises three subprograms and seven key projects covering the storage, disposal, and regulatory sectors of SNF management. Our program will last from 2021 through 2029, with a budget of approximately four billion USD sponsored by MSIT, MOTIE, and NSSC.