• Journal of Korean Institute of Industrial Engineers
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• v.13 no.2
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• pp.87-95
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• 1987

This article deals with the expected travel distances under Closest Open Location rule. In this paper it is shown that uniform distribution assumption over a rack, which is usually used when modeling randomized storage, is not valid under COL rule, where arrival loads follow Poisson process and duration times are independent of each other and have finite mean. We give both exact and approximate methods for the expected travel distances. Warehouse sizing problem is also included.

• Asian-Australasian Journal of Animal Sciences
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• v.9 no.6
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• pp.705-709
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• 1996

A simplified dilutor for cock spermatozoa at ambient temperature was achieved by adjusting the 5% concentration of fructose in isotonic saline. Motility of cock spermatozoa was arrested completely for maximum 6 hrs without affection the survivability of spermatozoa by employing this sugar. To study the effect of high concentration of fructose on fertility, sperm were inseminated with or without fructose at different hrs. Fructose from semen samples was removed by centrifugation. High fertility obtained in the hens inseminated with fructose free sperm (washed). In addition, washed sperm maintained the 85.00% fertility for 6 hrs in winter season ($17-21^{\circ}C$) and 82.67% fertility for 3 hrs in summer season ($31-35^{\circ}C$). Whereas control groups showed 47.33 and 25.33% fertility in winter and summer season respectively. No significant difference was found in percent motility and live counts between the control and washed experimental groups during winter season. However, these measures differed significantly in summer. Washing of cock spermatozoa more than once, high speed centrifugation and more duration for centrifugation proved harmful to fertility. It may be concluded that fructose (5%) can be used as a motility or metabolic inhibitor of spermatozoa for short-term storage of cock semen at ambient temperatures.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.1
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• pp.1-7
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• 2015

This paper proposes probabilistic reliability evaluation model of power system considering Wind Turbine Generator(WTG) integrated with Energy Storage System(ESS). Monte carlo sample state duration simulation method is used for the evaluation. Because the power output from WTG units usually fluctuates randomly, the power cannot be counted on to continuously satisfy the system load. Although the power output at any time is not controllable, the power output can be utilized by ESS. The ESS may make to smooth the fluctuation of the WTG power output. The detail process of power system reliability evaluation considering ESS cooperated WTG is presented using case study of Jeju island power system in the paper.

• Journal of the Korean Solar Energy Society
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• v.34 no.4
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• pp.1-7
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• 2014

The microgrid system is the combination of photovoltaic(PV) array, load, and battery energy storage system. The control strategies were defined as multi-modes of operation, including rest operation without use of battery, power charging, and power discharging, which enables grid connected mode or islanded mode. Photovoltaic power is a problem of the uniformity of power quality because the power generated from solar light is very sensitive to variation of insolation and duration of sunshine. As a solution to the above problem, energy storage system(ESS) is considered generally. There fore, in this study, we did basic research activities about optimization method of the amount of energy used, using a smart microgrid test-bed constructed in building. First, we analyzed the daily, monthly and period energy pattern amount of power energy used, and analyzed PV power generation level which is built on the roof. Utilizing building energy pattern analysis data, we was studied an efficient method of employing the ESS about building power consumption pattern and PV generation.

• Development and Reproduction
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• v.21 no.1
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• pp.79-91
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• 2017

The aim of this study was to compare the efficacy of cryopreservation methods for ex situ conservation of spermatozoa from far eastern catfish, Silurus asotus. The spermatozoa activity index (SAI) and hatching rates were higher in spermatozoa stored in Alserver's solution than those of spermatozoa stored in glucose solution. The SAI and hatching rates in all experimental groups gradually decreased with increasing duration of storage. Additionally, the SAI and hatching rates gradually decreased with increasing thawing temperatures at all storage durations (P<0.05). Based on the SAI and hatching rates, our results suggest that the optimal cryopreservation conditions of catfish spermatozoa involve storage in Alserver's solution with 15% ethylene glycol, and thawing at $25^{\circ}C$. Cryopreservation of spermatozoa is a useful and reliable technique for conserving gene resources and for artificial propagation of far eastern catfish.

• The Korean Journal of Food And Nutrition
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• v.25 no.1
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• pp.69-76
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• 2012

Intense pulsed light(IPL) has been highlighted as an innovative nonthermal sterilization technology that can kill spoilage or pathogenic microorganisms by using short-duration pulses of intense broad-spectrum electromagnetic radiation. This paper examines the inactivation effects of IPL on Listeria monocytogenes, Escherichia coli O157:H7, and Pseudomonas aeruginosa inoculated on seafood products such as salmon, flatfish, and shrimps and evaluates the possibility of extending the shelf-life of seafood products. The results indicate that the inactivation of microorganisms increased with an increase in IPL energy density($J/cm^2$) and a decrease in the distance between the sample surface and the lamp. In addition, temperature increases on the fish fillets during the treatments were well controlled within the range of 5.7~$9.8^{\circ}C$. The IPL treatment had a significant positive effect on the storage stability of seafood products at the storage temperature of $4^{\circ}C$ for 12 days. These results suggest that the storage period for fish fillets can be extended from 4 days to 6~8 days through the IPL treatment.

• Korean journal of food and cookery science
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• v.30 no.5
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• pp.596-602
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• 2014

Dutch coffee is extracted in low temperature for a longer time than espresso and drip coffee. This study was conducted to investigate changes in the flavor compounds in Dutch coffee resulting from different extraction times and storage days. The fifty six flavor compounds in Dutch coffee were identified using a headspace mass-spectrometer. Major flavor compounds were 2-furfuryl acetate, 5-methylfurfural, pyridine, furfural, 2-acetylfuran, pyridine, 2-methoxyphenol, furfuryl alcohol and some compounds varied with espresso and drip coffee. It was worthy of notice that more diverse compounds were composed of total flavor in Dutch coffee. There were more kinds of flavor compounds in early extracts than in latter ones. The duration of storage didn't significantly affected the peak area percentage of flavor compounds in Dutch coffee except with 2-furfuryl acetate.

• Horticultural Science & Technology
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• v.35 no.3
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• pp.314-322
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• 2017

The aim of this study was to determine suitable oxygen transmission rate (OTR) films for modified atmosphere (MA) storage of asparagus spears (Asparagus officinalis L.), and to examine the related changes in asparagus spear quality. Asparagus spears were packed with 10,000, 20,000, 40,000, 70,000, and $100,000cc/m^2{\cdot}day{\cdot}atm$ OTR film treatments for MA storage, and perforated film (conventional storage) was used as the control. The fresh weight loss rate was less than 1% in all OTR film treatments but not in the control. In all OTR film treatments, ethylene content rapidly increased on the first day of storage, and gradually decreased thereafter to $2.0{\mu}L{\cdot}L^{-1}$ by the final storage day. In the 10,000 cc and 20,000 cc OTR film treatments, carbon dioxide content was maintained within the permissible range for asparagus spears under recommended controlled atmosphere (CA) and MA conditions (5-12%). The oxygen content was maintained between 12% and 20% in all OTR film treatments. Hue angles and total chlorophyll content were highest in the 10,000 cc OTR film treatment in both tips and stems. Visual quality was maintained at a saleable level only in the 10,000 cc OTR film treatment until the final storage day (25 days). Based on sensory evaluation, the least off-odor was detected in the 10,000 cc OTR film treatment, and the most in the control treatment. While the soluble solids content decreased with all film treatments, it was maintained at the highest level in the 10,000 cc OTR film treatment. Vitamin C content decreased with all film treatments during storage, but was maintained at higher levels in the 10,000, 20,000, and 40,000 cc OTR film treatments. The firmness of tips and stems increased with storage duration in all film treatments, stems were firmer under the perforated film, 10,000, and 20,000 cc OTR film treatments. Given these results, the 10,000 cc OTR film treatment is considered the most appropriate for MA asparagus spear storage since visual quality and soluble solids content were maintained, and fresh weight loss, vitamin C content, off-odor, and yellowing were suppressed during storage.

• Journal of agriculture & life science
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• v.46 no.1
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• pp.1-8
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• 2012

Quality deterioration during storage such as weight and fruit firmness loss after harvest is one of the main problems in summer cultivation of mini paprika. Objective of this study was to determine appropriate storage temperature and duration in the mini paprika('Hivita Yellow' and 'Hivita Red'). More fruit firmness loss during storage was observed at higher storage temperature. Fruit firmness of 'Hivita Yellow' at $20^{\circ}C$ was $99.6g/cm^2$ after a 5-day storage whereas that decreased by $73.0g/cm^2$ after a 40-day storage. Storing 'Hivita Yellow' at $8^{\circ}C$ showed the lowest fruit firmness loss with 109.7 and $92.7g/cm^2$ after a 5-day and a 40-day storage, respectively. In both cultivars, soluble solids content of fruits was higher at $20^{\circ}C$ than at 4, 8 and $12^{\circ}C$. Higher temperature triggered more water loss of the fruits with more occurrence of soft rot and shriveling symptoms. The changes in electrolyte conductivity of fruits during storage was higher in the fruits at lower temperature. Fruit stored at $20^{\circ}C$ showed the highest respiration(more $CO_2$ and less $O_2$) during storage than fruits at the other storage temperatures.

• Food Science and Preservation
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• v.15 no.6
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• pp.791-795
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• 2008

In order to establish the method to prepare and use the sulfur dioxide gas generating agent in low temperature storage of grape fruits, the $SO_2$ generation capacity from various sulfite compounds was investigated, and the method to regulate $SO_2$ gas generation and to detect the gas was developed. The conidial germination and mycelium growth of Botrytis cinerea which causes gray mold disease during grape fruit storage was completely inhibited at the $SO_2$ gas concentration of 400 ppm and 3200 ppm, respectively. Sodium hydrosulfite generated the most amount of $SO_2$ gas among the investigated 5 different sulfite or bisulfite compounds. By adjusting the number of pinholes on packaging film of the compound or by adding pH adjusting agent, e.g. citric acid or phosphates, it was possible to regulate the amount and duration of $SO_2$ gas generation from the compound. Because malachite green was quantitatively discolored by $SO_2$ gas, the solution or impregnated paper with the compound could be practically utilized as a indicator detecting $SO_2$ gas. Finally, when Muscat Bailey A grape was stored at low temperature with $SO_2$ gas generating agent, the disease incidence was reduced after storage.