• Food Science and Biotechnology
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• v.18 no.6
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• pp.1379-1385
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• 2009

Quality changes of the slices processed from 'Niitaka' Asian pears (Pyrus pyrifolia) stored at $0^{\circ}C$ for up to 4 months under controlled atmosphere (CA, 1% $O_2+1%\;CO_2$) and normal air have been investigated for 4 days at $10^{\circ}C$. Respiration rate of the slices was retarded by pre-slicing storage for 4 months in CA. Electrolyte leakage was lower in the slices from pears stored for short-term than long-term and under CA than air. L and a values of the slices from whole pears stored under CA were maintained higher and lower, respectively as compared to the other. Levels of acetaldehyde and ethanol in the slices were increased by CA and long-term storage of whole pears. Content of ascorbic acid and counts of total aerobic microbes in the slices were not affected by storage conditions of whole pears. These results show that storage atmospheres and durations of whole pears affected quality changes of the slices and the conditions of pre-slicing storage should be considered as an important factor for optimizing fresh-cut procedures.

• Journal of Korea Water Resources Association
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• v.41 no.7
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• pp.737-746
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• 2008

The purpose of developing a rainfall-runoff and reservoir model is to provide an analysis tool for hydrological engineers in order to forecast discharge of rivers and to accomplish reservoir operations easily and accurately. In this study, based on the short-term rainfall-runoff storage function model which has gained popularity for real time flood forecast in practical water management affairs, a long-term runoff model was developed for the improvement of the calculation method of effective rainfall and percolation at the infiltration area. Annual discharge was simulated for three dam watersheds(Andong, Hapcheon, Milyang) in Nakdong River basin to analyze the accuracy of the developed model and compare it to SSARR model, which is used as the long-term runoff model in current practical water management affairs. As the result of the comparison of hydrographs, SSARR model showed relatively better results. However, it is possible for the developed model to simulate reliable long-term runoff using relatively little available data and is useful for hydrological engineers in practical affairs.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.11 no.4
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• pp.333-349
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• 2013

As the capacity of spent nuclear fuel storage pool at reactor sites becomes saturated in ten years, long term dry storage strategy has been recently discussed as an alternative option in Korea. In this study, we reviewed safety-criteria-related research results on spent nuclear fuel performance and integrity under long-term dry storage and proposed the direction and the scope of future domestic research and development. Creep and hydride effect in relation to the embrittlement are known to be the major degradation mechanisms of the spent fuels during the long term dry storage. However, recent research results showed that hydride reorientation and hydride embrittlement are one of the most critical factors to the spent fuel integrity. Accordingly safety criteria of US and Japan for the storage system are basically founded on those mechanisms. However, in Korea, not only in-pile but out-of-pile experimental data have not been generated to understand fuel cladding degradation and to determine the criteria to ensure the safety. In addition, the transient behavior of the spent fuel during transportation also needs to be thoroughly examined. Therefore, various experimental research and development will be required to establish our own safety criteria for future long-term dry storage of domestic spent fuels.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.20 no.2
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• pp.255-258
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• 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.

• Journal of Biosystems Engineering
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• v.39 no.3
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• pp.194-204
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• 2014

Purpose: The aim of this study was to develop long-term storage technology for Chinese cabbage in order to extend the period of availability of freshly harvested products. The scope of the paper deals with the use of a cooler with a remote monitoring and control interface in conjunction with use of packaging film. Methods: A cooler with a real time monitoring system was designed as a low-temperature storage facility to control temperature and relative humidity (RH). The effects of storage in high-density polyethylene (HDPE) plastic boxes, 3% chitosan dipping solution, polypropylene film (PEF) with perforations, and mesh packaging bags on physiological responses were investigated. The optimal storage temperature and humidity for 120 days were below $0.5^{\circ}C$ and 90%, respectively. Physiological and biochemical features of cabbage quality were also analyzed: weight loss, texture, and sugar salinity, chlorophyll, reducing sugar, and vitamin C contents. Results: The cooler with a remote monitoring and control interface could be operated by an HMI program. A $0.5^{\circ}C$ temperature and 90% humidity could be remotely controlled within the cooler for 120 days. Postharvest freshness of Chinese cabbages could be maintained up to 120 days depending on the packaging method and operation of the remote monitoring system. In particular, wrapping the cabbages in PEF with perforations resulted in a less than a 5% deterioration in quality. This study provides evidence for efficient performance of plastic films in minimizing post-harvest deterioration and maintaining overall quality of cabbages stored under precise low-temperature conditions with remote monitoring and a control interface. Conclusions: Packaging with a modified plastic film and storage in a precisely controlled cooler with a remote monitoring and control interface could slow down the physiological factors that cause adverse quality changes and thereby increase the shelf life of Chinese cabbage.

• Journal of Animal Science and Technology
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• v.63 no.4
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• pp.884-891
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• 2021

The study aimed to evaluate pork loin quality after short-term (ten-day) storage in a supercooling refrigerator. Pork loin samples were stored for 10 days in a traditional refrigerator (control) and a commercially available supercooling refrigerator (SC). Pork quality measurements included meat pH, meat color, water holding capacity (drip loss and cooking loss), tenderness (hardness), and a sensory evaluation. Temperature changes of 0.45 ± 0.2℃ and 0.02 ± 0.25℃ occurred in the control and the SC, respectively, during 10 days of storage. The temperature in the SC chamber did not remain below freezing point, failing to meet expectations. Regarding the pork quality measurements, only the drip losses in the control and the SC were significantly different (4.45% vs. 2.59%, p < 0.01) after 10 days of storage. There were no significant differences between the two types of refrigerator in terms of the other measurements. Additionally, the overall acceptability of the pork loin did not vary significantly between the control and the SC when the sensory evaluation was performed. Therefore, a commercial SC could prove beneficial in terms of water holding capacity during the short-term storage of meat. Further research should be performed to evaluate quality changes that occur during long-term storage of meat in SC s and evaluate a wide range of meat, such as beef and chicken.

• The Korean Journal of Physiology and Pharmacology
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• v.18 no.6
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• pp.457-460
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• 2014

At central synapses, activity-dependent synaptic plasticity has a crucial role in information processing, storage, learning, and memory under both physiological and pathological conditions. One widely accepted model of learning mechanism and information processing in the brain is Hebbian Plasticity: long-term potentiation (LTP) and long-term depression (LTD). LTP and LTD are respectively activity-dependent enhancement and reduction in the efficacy of the synapses, which are rapid and synapse-specific processes. A number of recent studies have a strong focal point on the critical importance of another distinct form of synaptic plasticity, non-Hebbian plasticity. Non-Hebbian plasticity dynamically adjusts synaptic strength to maintain stability. This process may be very slow and occur cell-widely. By putting them all together, this mini review defines an important conceptual difference between Hebbian and non-Hebbian plasticity.

• Animal Bioscience
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• v.37 no.2
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• pp.210-217
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• 2024

Objective: This study investigated the efficacy of different concentrations of gelatin supplementation in long-term semen extender on boar semen quality during storage for 10 days at 17℃. Additionally, oxytocin was added to stored semen to enhance fertility. Methods: In Experiment 1, boar semen was collected, diluted with gelatin at concentrations between 0% and 2.5% (w/v) and mixed with a semen extender. Then, it was kept in a refrigerator at 17℃ and stored for 10 days. In Experiment 2, the sperm quality was examined after adding 0, 5, and 10 IU oxytocin per artificial insemination dose to the most effective semen extender from Experiment 1 and placing it in a refrigerator at 17℃ for 10 days. In Experiment 3, the fertility potential in terms of non-return rate and litter size was determined using the most effective solid-stored semen supplemented with oxytocin. Results: The results indicated that sperm quality decreased with increasing storage time (p<0.05). The sperm quality in terms of total motility, progressive motility, and viable sperm with intact acrosomes and high mitochondrial potential was the highest with 1.5% gelatin supplementation (p<0.001) on all days of storage. Treatment with oxytocin did not affect sperm quality (p>0.05). The non-return rate and litter size after insemination with semen supplemented with 1.5% gelatin and 10 IU of oxytocin after 8 to 10 days of storage were comparable to those of the control group (p>0.05). Conclusion: A semen extender as a solid medium supplemented with 1.5% gelatin successfully preserved boar semen for a long storage duration. Treatment with oxytocin did not affect sperm quality. In addition, the fertility capacity using 1.5% gelatin with 10 IU oxytocin and stored for 8 to 10 days was acceptable and comparable to that of short-term storage.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1996.10b
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• pp.193-205
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• 1996

This paper deals with experimental study on thermal characteristics that a cooling fluid is affected to ice ball as being measuring the temperature in storage tank and ice ball governing the rate of heat storage. Distributor was taken as inlet geometry factor. flow rate of cooling fluid which was a brine were 2, 4, and 6LPM, and 8, 10, and 12$^{\circ}C$ in the temperature difference for dynamic factors with respect to three ice ball types(103, 96, 76mm). In case of in flowing cooling fluid, since inertia force is suppressed by lower flow rate the amount of heat was transferred to ice ball by heat conduction high because density difference is high. And in case of larger ice ball, a long-term storage was available because reaching time at steady state is relatively long. consequently, smaller ice ball could be suitable to a short-term storage.

• Tribology and Lubricants
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• v.34 no.5
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• pp.197-207
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• 2018

Thermal deterioration of fuel due to long-term storage influences engine performance and causes malfunctions. Fuel stability is usually evaluated via heat resistance and thermal stability during a brief heat shock at high temperature; storage stability in this scenario means that there is very little change in the quality of the fuel during long-term storage. In addition, rubber-based products such as oil seals, O-rings, and rubber hoses can influence the quality of the fuel. When these rubber products are in contact with fuel, they can swell, mechanically weaken, and occasionally crack, thus leaking low molar weight rubber and additives including plasticizer and antioxidant into the fuel to degrade its properties and shorten its useful lifetime. This study determines the thermal stabilities of three kinds of synthetic fuels by evaluating their low temperature kinematic viscosities, chemical composition changes via GC analyses, gross heat of combustion, and color changes. We evaluate the compression set of O-rings by immersing one NBR and two FKM rubber O-rings in the three synthetic fuel samples in airtight containers at variable storage temperatures for six months; from this, we estimate the lifetimes of the O-rings using the Power law model. There were very little changes in the chemical compositions and gross heat of combustion after six months of the experiment. The lifetimes are thus dependent on the materials of the rubber products, and in particular, the FKM O-ring was calculated to have a theoretical lifetime of 200 to 5,700 years. These results indicate that the synthetic fuels maintain their physical properties even after long-term storage at high temperatures, and the FKM O-ring is suitable for long-term sealing of these fuels.