• Journal of the Korea Concrete Institute
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• v.20 no.6
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• pp.721-729
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• 2008

The purpose of this study is to investigate the engineering properties of concrete for the early strength development. As a result of reviewing it by establishing each experimental factor and level, the cement had more excellent quality performance in CHC and HESPC than OPC. This study has shown that the PC series admixture was more excellent in side of elapsed time (aging) and early strength development than PNS series admixture. In addition, there was much difference according to the curing temperature, but the early strength development showed the considerable vulnerability in curing temperature below $12^{\circ}C$. To satisfy the strength requirements of 5 MPa/18 hr this study has shown that it needed the curing temperature over $17^{\circ}C$ to the minimum in OPC, over $14^{\circ}C$ in CHC, and over $11^{\circ}C$ in HESPC. On the other hand, as to the strength properties according to W/C, the less W/C was, the more strength development was excellent. If this study is to be used in construction filed on a basis of this result, this researcher is considered as possible of the economic execution of construction by advancing the early strength and by the reduction of construction cost according to shortening construction duration.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.23 no.1
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• pp.27-36
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• 2017

In order to determine the relationship between water content and flower qualities of oriental hybrid lily cv. 'Siberia' cut flower, flowers were subjected to dry and cold storage at $5^{\circ}C$ for 3, 6, and 12 days and subsequently exposed to ambient temperature ($26^{\circ}C$) in bottles with water for up to 16 days. Flowers stored at $22^{\circ}C$ in dry condition for 3 days were used as the control. Changes in fresh weight, moisture content, water balance, flowering stages, osmolality and vase life of cut flowers were observed. Flowers treated with cold and dry storage had higher moisture content compared to control sample. However, this trend was evident only for 3-day cold and dry stored sample during the whole storage period. The fresh weight of cut flowers increased gradually when the samples were transferred to ambient temperature in water bottles and then declined steadily before reaching the peak in between 6-8 days of vase life. However, the changes of fresh weight of control sample were substantially faster than samples pre-treated with cold and dry storage. This was also correlated with the water balance of cut flower as it reached the minus (-) value in 6-8 days of vase life at ambient temperature. Cut lily flowers showed high osmolality values corresponding with the duration of dry storage regardless of low or higher temperature. However, osmolality had no effect on vase life since flower stem absorbed water rapidly at the end of dry storage period. Our vase life results suggest that cold and dry storage of lily cut flowers for a certain period could ensure longer vase life at ambient temperature. It was observed that prolonging the storage period at cold and dry condition for more than a week significantly increased bud abortion, reduced longevity of flowers and reduced the vase life of cut flowers. On the other hand, the shorter cold and dry storage treatment delayed the bud opening and senescence of the flowers, thus, slowering the normal maturation and aging. Results indicated that dry and cold storage at $5^{\circ}C$ for 3 days was effective in maintaining and preserving overall quality and vase life at ambient condition of oriental hybrid lily cut flowers.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.6
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• pp.800-806
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• 2007

This study investigated the quality characteristics of kiwi wine during low temperature aging on several alcohol fermentation strains. Alcohol content increased sharply from 2 days of fermentation, and then maintained steadily after 8 days of fermentation. In the alcohol content of kiwi wine on several alcohol fermentation strains such as Sacch. cerevisiae GRJ, Sacch. kluyveri DJ97 and Sacch. cerevisiae Wine 3 showed a high value of more than 13%, 12.7% for Zigosacch. cerevisiae JK99 and 12.3% for Sacch. cerevisiae OMK, respectively. Sugar content decreased steadily during fermentation and then showed approximately $10^{\circ}$Brix on 8 days of fermentation. Total acidity ranged $1.03{\sim}1.04%$ in total samples, increased slowly during fermentation and then maintained steadily during aging. During the fermentation, L value in Hunter's color value continued to increase, a value decreased steadily and b value showed high yellow to approximately 20.0. For aging duration, L and b values decreased while a value increased. Glucose and maltose were detected as free sugars of kiwi wine. In volatile flavor compounds, alcohols were identified differently on alcohol fermentation strains, but the others showed similar tendency. In conclusion, quality characteristics of kiwi wine on several alcohol fermentation strains showed similarly; however, Sacch. cerevisiae Wine 3 was overall the most suitable.