• KSBB Journal
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• v.29 no.5
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• pp.385-391
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• 2014

In this study, the emulsion dispersion stability of optimizing storage temperature was investigated. The system was based on oil/water (O/W) emulsions. In order to evaluate the stability, mean diameter of droplet was measured as a function of temperature with various mixed hydrophilic lipophilic balance (HLB). In addition, the correlations between phase inversion temperature (PIT) and the optimum storage temperature were probed. In this system, majority of the smallest droplet was shown at temperature of $20^{\circ}C$ below PIT. Whether the temperature was increased or decreased from the optimum, size of the droplet increased. According to the mixed HLB, the particle size and optimum storage temperature were also affected. As the concentrations of surfactant were increased, the size of particle decreased with lower optimum temperature for storage. If the surfactant (4 wt%) were mixed with HLB, the optimum storage temperature was $21^{\circ}C$ for maintaining the size of smallest droplet at 108.3 nm in diameter. At above optimum condition, increased size of particle was observed approximately 4 % increases from 108.2 nm to 112.3 nm after 600 hours. The size of particle in emulsion was maintained stably without any considerable effect of Ostwald ripening phenomena at the optimum storage temperature with low polydispersity index.

• Food Science and Preservation
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• v.4 no.2
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• pp.115-122
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• 1997

This experiment was hocused on the improvement of postharvest management of fresh shiitake to increase the marketing duration. the respiration rate of fresh shiitake at 2$0^{\circ}C$ was ranged from 395mg to 551mg CO2/kg/hr depending on the cultural condition. The rapid precooling is considered as one of the most important postharsvest management to remain shiitake quality. The optimum temperature for precooling and storage was -3$^{\circ}C$ because the occurrence of physical damage on frozen tissue at below -5$^{\circ}C$. Frozen storage at -3$^{\circ}C$ had benefits to minimize weight loss, browning induction at gill tissue and consumption of stored materials where as storage at $0^{\circ}C$ appeared not to be adequite for the extension of marking duration. Frozen shiitake was succesefully thawed when exposed to RH 40-50% at below 1$0^{\circ}C$.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.4
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• pp.717-725
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• 2011

In the power system with an electric storage system that can increase utilization rate of the source of such new renewable energy, this paper introduces the approach on the daily unit commitment scheduling that determines simultaneously optimum operational condition and output of thermal generators and electric storage device. The unit commitment is one of the most important issues in economic operation and security of short-term operational plan of the power system. It is to determine on/off status of generator to minimize operational cost during the given period. The committed generator should satisfy various operational limitation such as estimated demand by system, spinning reserve condition within minimum operational cost. In order to determine on/off or charge/discharge/idle condition and output level of units and electric storage system, the MILP(Mixed Integer Linear Programming) is suggested. The proposed approach is the mixed method between LP(Linear Programming) and IP(integer programming) which seeks the value of real number and integer that maximize or minimize function objective within given condition. The daily unit commitment problem with the electric storage system is applied to MILP algorithm through linearization and formulation process. The proposed approach is applied to the test system.

• Journal of the Korean Society of Clothing and Textiles
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• v.21 no.1
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• pp.228-236
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• 1997

The browning characteristic and dyeability of the mushroom were examined to establish the optimum condition for browning and extraction in the process of obtaining the natural dye, brown colorant. The composition of browning extracts from mushroom was also analyzed and the dyeability were investigated. The results of this study are as follows, 1. The optimum condition for obtaining the browning colorant from mushroom was the crushed phase of sample. 2. The browning reaction by enzymes in mushroom was efficient at a temperature of 35$^{\circ}C$, a duratron period of 2 hr and pH of 8. 3. The optimum condition for extraction of browning extracts from browned mushroom was at 95$^{\circ}C$ and Ihr. 4. To analyze the content of browning extracts in the mushroom, three fractions were obtained from gel filtration using Sephadex G-25 and the fraction 1 was melanin and the fraction 3 was dihydroxyphenylanine (DOPA) and glutaminyldihydroxybenzene (GDHB) . 5. The turbidity in enzymatic browning extraction of mushroom increased depending on refrigeration storage (4$^{\circ}C$) and UV radiation. The filtration of the extracts resulted in a decrease of absorbance. 6. The dyeability of the fraction 1 was greater compared to that of the fraction 3 and that of wool greater compared to the other two fabric materiales.

• 한국태양에너지학회:학술대회논문집
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• 2009.11a
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• pp.409-414
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• 2009

Since cryogens are stored at very low temperatures, the cryogenic storage systems are quite sensitive to heat leaks. Even though the vessel operated under sealed condition with vacuum insulation and reflective coatings are used, the heat leakage into the vessel is still unavoidable. Therefore, this paper concerns with numerical study of self-pressurization used to analysis the optimum design with the variation volume fraction, effect of heat flux and storage pressure of liquid nitrogen. The result shows that as the volume fraction increases, the pressure rise reduces and the relatively at atmosphere pressure is better than the higher one. In addition, higher heat flux leads the pressure rise increases faster than low one. The additional of heat pipe system to reduce the pressure rise rate also has been done. By this comparison, the optimum design for storage umbilical cord blood can be selected.

• Korean Journal of Plant Resources
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• v.19 no.3
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• pp.436-439
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• 2006

This study was carried out to obtain basic information for optimum storage method of leaf, stem and root of Angelica acutiloba Radix, which is being utilized as major cultivated herbal medicine materials, root of Angelica acutiloba was stored for 3 months in different packing materials and sealing methods, such as punched packing, sealing and vacuum packing. The results are summarized as follows. The loss in weight as influenced by packing materials and sealing degree was the lowest at vacuum packing and complete sealing condition with transparent polyethylene film. The ratio of root rot during the storage period was not significantly different between polyethylene films, but it was significantly different between sealing conditions. Therefore, vacuum packing and complete sealing with polyethylene film are desirable storage condition for Angelica acutiloba Radix.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.26 no.7
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• pp.322-328
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• 2014

Return piping is used in a solar combi-system for heating and hot water supply. When the temperature of the lower side of a storage tank is low due to hot water usage, the returned hot water after heating is mixed with the lower side cold water of the tank, and the useful energy is reduced. We studied the degree of thermal stratification in the tank, using either a diffuser or a manifold to prevent mixing. Using the diffuser, mixing starts from the bottom of the storage tank. On the other hand, the manifold has the marked effect of preventing mixing. As a result of experiments with changing the diameter and number of holes in the manifold, the optimum condition is 8.5 mm diameter and 96 holes, under the condition of 0.3 lpm.

• Food Science and Preservation
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• v.1 no.1
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• pp.15-20
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• 1994

This experiment was carried out to select the optimum thickness of polyethylene film for the nonastringency of astringent persimmon fruits during modified atmosphere(MA) storage of Cheongdo Bansi kept at 0$^{\circ}C$. The experimental plots were divided into 5 plots by film thickness(0.08, 0.10, 0.12, 0.14 and 0.16mm). The experimental items were the changes in concentration of CO2 and O2 in film brig, soluble tannin contents, loss of weight firmness and external appearance of fruits. The nonastringency of persimmon fruits can be achieved all groups excepting the 0.08mm film during MA storage. The sweet persimmon in film bag of 0.10 and 0.12mm maintained a high quality and firmness, but following the deastringency the fruits in 0.14 and 0.16mm developed off-color. The increasing of carbon dioxide level and decreasing of oxygen level in film bag created anaerobic condition at earth stage, and then it kept a constant level during stooge. According to film thickness the obvious difference in the change of soluble tannin contents external appearance and firmness were observed. It could be concluded that the optimum thickness of film for the desirable nonastringency on Cheongdo Bansi was 0.10mm.

• The Research Journal of the Costume Culture
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• v.7 no.2
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• pp.315-322
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• 1999

The acquistion and dyeability of the Gardenia jasminoides were examined to establish the optimum condition for extraction and storage in the process of obtaining the natural dye, Gardenia jasminoides colorant. Also the dyeability and colorfastness of Gardenia jasminoides were investigated. The results of this study are as follows. The optimum part-removed seed. In all experiments, the part of fat-removed seed and pericarp was used. The optimum condition for extraction of Gardenia jasminoides colorant was at 40℃ and for 90 min. in methanol. As storage temperature was higher, the absorbance of colorant extract decreased rapidly. The Gardenia jasminoides colorant exhibited dyeability to cotton, silk, wool, and nylon. The dyeability was the greatest in wool, and then nylon, silk, and cotton. Both wool and nylon had the greatest K/S value at pH3, however, nylon and cotton at pH 6 and pH 8 respectively. In addition, the increase in K/S value corresponded to temperature in wool and nylon, but the silk and cotton had the greatest K/S value at 60℃. Also, the K/S value increased in concomitant with the increased number of dyeing repetition. In the most cases, colorfastness of light was weak but colorfastness of laundry, sweat was relatively excellent.

• Journal of the East Asian Society of Dietary Life
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• v.16 no.4
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• pp.438-446
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• 2006

The aim of this study was to determine the optimum storage time of flounder and seabream for the preparation of flatfish and sushi. With increasing storage time(0-6 hours) at 4$^{\circ}C$, the moisture, -and fat contents of flounder and seabream flatfish decreased while the total number of bacteria increased. Eicosapentaenoic acid and palmitic acid had the highest content in the flatfish fatty acid composition. The pH of flounder and seabream flatfish both decreased at 4 and 3 hours, respectively, and then increased. With increasing storage time, the hardness and cohesiveness decreased, while the springiness, gumminess,-and chewiness initially increased but then decreased. The rigor mortis increased with increasing storage time and the K values of flounder and seabream flatfish both increased at 4 and 3 hours, respectively, and then decreased, whereas ATP contents decreased and then increased. In the sensory evaluation of sushi, the flounder sushi with flatfish stored for 4 hours and the seabream sushi with flatfish stored for 3 hours were found to be the best making condition.