• Korean journal of food and cookery science
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• v.22 no.3 s.93
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• pp.337-345
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• 2006

The properties of various grains used for the solid-state cultivation of basidiomycetes were examined. The hydration time with cold water was 10 hours for malt soybean. The required hydration time for Job's tears, barley and wheat was 4, 6 and 12 hours, respectively, but the final moisture content ranged from 30 to 48 %, which was much less than the optimum moisture content for mycelial growth. For the mass cultivation of mycelia, the hydrated grains with cold water were placed in plastic bottles. The mycelial growth ra in e bottled grains was high in the early stage with inoculation of homogenized mycelium. The mycelium activity was maintained by adding sterilized water in the middle of the cultivation period. Jupjang underwent sensory evaluation to examine the possibility of utilizing basidiomycetes in functional foods. The grains fermented with Ganoderma lucidum was the best for Jupjang. The combination of malt soybean and Job's tears was the best for Jupjang. The acceptability of Jupjang was improved during the period of aging time.

• Elastomers and Composites
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• v.55 no.2
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• pp.81-87
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• 2020

Service life prediction and evaluation of rubber components is the foundational technology necessary for securing the safety and reliability of the product and to ensure an optimum design. Even though the domestic industry has recognized the importance thereof, technology for a systematic design and analysis of the same has not yet been established. In order to develop this technology, identifying the fatigue damage parameters that affect service life is imperative. Most anti-vibration rubber components had been damaged by repeated load and aging. Hence, the evaluation of the fatigue characteristics is indispensable. Therefore, in this paper, we propose a method that can predict the service life of rubber components relatively accurately in a short period of time. This method works even in the initial designing stage. We followed the service life prediction procedure of the proposed rubber components. The weak part of the rubber and the maximum strain were analyzed using finite element analysis of the rubber bushing for the tracked vehicles. In order to predict the service life of the rubber components that were in storage for a certain period of time, the fatigue test was performed on the three-dimensional dumbbell specimen, based on the results obtained by the rubber material acceleration test. The service life formula of the rubber bushing for tracked vehicles was derived using both finite element analysis and the fatigue test. The service life of the rubber bushing for tracked vehicles was estimated to be about 1.7 million cycles at room temperature (initial stage) and about 400,000 cycles when kept in storage for 3 years. Through this paper, the service life for various rubber parts is expected be predicted and evaluated. This will contribute to improving the durability and reliability of rubber components.

• Korean journal of food and cookery science
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• v.24 no.6
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• pp.837-848
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• 2008

The objectives of this study were to investigate the quality of ginseng makgeolli during the fermentation and aging period, and to develop Jeungpyun manufactured by ginseng makgeolli. Four different amounts of ginseng powder (0, 2, 4 and 6 g) were added to the filtered mash which was fermented for 4 days at $24^{\circ}C$ and then aged for 6 days at $4^{\circ}C$ The quality of Jeungpyun batter containing 0, 2, 4 and 6% ginseng during fermentation, and the sensory, color and textural characteristics of ginseng Jeungpyun were analyzed. The pH of jeungpyun batter without ginseng was lower than the other batters. During 4 hours of fermentation of the batter at $30^{\circ}C$, the pH of the batter significantly decreased. The expansion volume of the batter without ginseng increased 4.11 times after 4 hours of fermentation, whereas batters with 2, 4, and 6% ginseng increased 1.70 times. The L value of Jeungpyun decreased by increasing the concentration of ginseng However the a and b values of Jeungpyun significantly increased with an increase in the concentration of ginseng. The results of the sensory evaluation showed that Jeungpyun with 2% ginseng had the highest flavor, taste and overall acceptability scores. In the textural analysis, the hardness of Jeungpyun increased by increasing the concentration of ginseng after 6 days of storage at $20^{\circ}C$. This study showed that Jeunpyun containing 2% ginseng was the optimum addition level.

• Korean Journal of Agricultural Science
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• v.8 no.2
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• pp.133-138
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• 1981

Effect of the seeding rate and nursery period on the growth and characteristics of seedling suitable for rice transplanter was analyzed and the following results were obtained. The optimum seeding rate were about 100 to 150g in the 30 day old seedling, and 150g per nursery box in the 25day old seedling, respectively, as having adequate leaf number, plant height, dry weight, hardiness and crop growth rate for transplanting. Excessively low and high seeding rate resulted in excessive aging and weakness of the seedling at the later growth stages.

• Korean Journal of Food Science and Technology
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• v.40 no.2
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• pp.238-242
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• 2008

In this study, hydrogen sulfide ($H_2S$) production was examined during beer fermentation using two ale and two lager yeast strains. In the lager yeast fermentation, a large amount of $H_2S$ was produced in the early fermentation stages when the yeast were actively fermenting wort, indicating a positive relationship between the level of H2S production and the yeast growth rate during fermentation. The ale yeasts produced much lower levels of H2S than the lager yeasts. In the lager fermentation, a higher fermentation temperature shortened the fermentation period, but much higher levels of $H_2S$ were produced at higher temperatures. American pilsner lager yeast fermenting at $15^{\circ}C$ produced a relatively high level of $H_2S$ at the end of fermentation, which would require a longer aging time to remove this malodorous volatile sulfur compound. Not including the English ale strain, which produced a higher level of H2S at lower temperatures, the ale yeast produced lower levels of $H_2S$ at lower temperatures, suggesting that each strain has an optimum fermentation temperature for H2S production.