• Journal of the Society of Naval Architects of Korea
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• v.40 no.6
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• pp.80-87
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• 2003

Tank structures in ships are in contact with various fluid. The vibration characteristics of those structures are strongly affected by the added mass due to containing fluid. It is important to predict vibration characteristics of tank structures, but it is difficult to do. That's because the interaction problem concerned with the free surface, the variation of water depth and stiffener is to be considered between the fluid and the structure. Many authors have studied vibration of rectangular tank structures containing water. Kito studied added mass effect of water in contact with thin elastic flat plates. Kim et al. studied flexural vibration of stiffened plates in contact with water. However, few researches on dynamic interaction tank walls with water are reported in the vibration of rectangular tanks recently. in the present report, the coupling effect of added mass of fluid and structural constraint between panels on each vibration mode changing breadth of elastic plate, and dynamic pressure distribution have investigated numerically and discussed.

• Korean journal of food and cookery science
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• v.25 no.2
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• pp.160-169
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• 2009

This study was performed to examine the quality characteristics of red ginseng wet noodles prepared with additions of carrageenan, xanthan gum, or guar gum. The quality characteristics of the samples were estimated in terms of their general composition, color differences, cooking characteristics, textural attributes, sensory qualities, and microbial growth during storage. The results were as follows. Protein content was significantly decreased in the guar gum added group and ash content was significantly increased in the carrageenan added group (p<0.05). Lipid, water, and Na contents were not significant different among the groups. However, water binding capacity was significantly increased in the group with added xanthan gum. Over 10 weeks of storage, water contents did not differ significantly between the xanthan gum and guar gum added groups. In all the added gum groups, L- and a- values were significantly increased whereas b- values decreased (p<0.05). In texture profile analyses, chewiness, cohesiveness, hardness, and springiness were significantly increased in the carrageenan and xanthan gum added groups (p<0.05). According to sensory evaluations, surface color, red ginseng flavor, red ginseng taste, softness, chewiness, and overall acceptability were considered very good in the xanthan gum and guar gum added groups (p<0.05). Therefore, the red ginseng noodles containing xanthan gum and guar gum were deemed most preferable and presented the safest shelf-life during 10 weeks at -$10^{\circ}C$.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.6
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• pp.42-49
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• 2020

This paper is a basic study to improve durability by imparting hydrophobicity to the surface and sphere of cement-based materials. A cement mortar to which a silane/siloxane-based mixed water repellent was added was prepared, and its initial hydration performance, flow performance, and compressive strength were measured. In addition, after the surface was abraded, the water contact angle and water absorption were measured. The flow of cement mortar to which the water repellent was added was found to decrease up to 1.5% in the addition amount of the water repellent agent, and increased at 3.0% in the addition amount. It was found that the setting time of the cement paste was delayed in both the initial setting and the termination when the water repellent was added. It was found that the compressive strength decreased from 3.0% of the maximum added amount of the water repellent to a maximum of 30%. The contact angle was found to increase when the water repellent was added to the cement mortar, and the contact angle after surface polishing was found to be larger than before surface polishing. The addition of the water repellent showed hydrophobicity not only on the surface but also on the surface and cross section damaged by polishing. The water absorption rate was found to decrease when the water repellent was added to the cement mortar, and the water absorption rate after surface polishing was found to be greater than before surface polishing.

• Journal of the East Asian Society of Dietary Life
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• v.20 no.4
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• pp.589-595
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• 2010

The purpose of this study was to investigate the practical application and optimum conditions for adding functional dropwort, which is rich in physiological activity to Sulgidduk, toward developing dropwort-added dduk as a healthy food. To this end, samples of Sulgidduk with 0, 1, 3, 5 and 7% added dropwort powder were prepared, stored for 2 days at $20^{\circ}C$, after which the water content, chromaticity, and mechanical and sensory quality characteristics were measured. The results were as follows. The water content of nonglutinous rice powder and dropwort powder used for dropwort-added Sulgidduk was 41.73% and 3.5%, respectively. The water content decreased with increasing amounts of dropwort powder the group with 7% added dropwort powder was 33.88%, the lowest. For chromaticity, the L value decreased with increasing amount of dropwort powder with significant differences between groups with different added amounts (p<0.001). The a and b values increased with increasing amount of dropwort powder while they were 7.21 and 29.22, respectively, in the 7% dropwort powder-added group with significant differences between samples (p<0.001). For mechanical quality characteristics hardness decreased with increasing of amount of dropwort powder with significant differences between samples (p<0.001). There was no difference between samples in cohesiveness and springiness. Gumminess increased with increasing amount of dropwort powder with significant differences between samples (p<0.05). Chewiness and adhesiveness had a tendency to decrease with increasing amounts of dropwort powder. Overall acceptability was in the order of 3%, 5%, 1%, 7%, and 0% dropwort powder-added groups. Overall, for dropwort powder added Sulgidduk, the quality of flavor, color and taste was acceptable, compared to other powder-added groups. The 3% dropwort powder-added group was highly rated in general preference making it most desirable for making dropwort powder-added Sulgidduk.

• Journal of the Society of Naval Architects of Korea
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• v.40 no.4
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• pp.46-52
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• 2003

In ship structures, many parts are in contact with inner or outer fluid as stern, ballast and oil tanks. Fatigue damages can be sometimes observed in these tanks which seem to be caused by resonance. Tank structures in ships are in contact with water and the vibration characteristics are strongly affected by the added mass of containing water. Therefore it is important to predict vibration characteristics of tank structures. In order to estimate the vibration characteristics, the fluid-structure interaction problem has to be solved precisely. In the present paper, we have developed a numerical tool of vibration analysis of 3-dimensional tank structures using finite elements for plates and boundary elements for water region. To verify the present analysis, we have made an experiment for vibration characteristics of a tank with elastic opposite panels. And the added mass effect of containing water and the effect of structural constraint between panels are investigated numerically and discussed.

• Korean journal of food and cookery science
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• v.10 no.4
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• pp.334-338
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• 1994

When total amount of water, including Takju(15%, w/w), was added differently in the ranges of 30 to 60% of the weight of rice flour, the specific volume of Jeungpyun had the highest value in the sample with 45% of water added. The Jeungpyun with 45% of water added also showed the best acceptability by means of taste evaluation. Dough viscosity was decreased by two stages of rapid and slow phase in logarithmic mode as total amount of water was increased and the turning point was observed at 45% of water.

• Journal of the Korea Institute of Building Construction
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• v.8 no.1
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• pp.91-96
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• 2008

This study is to investigate the influence of the over-added chemical agents, such as water reducing agent(WRA) and AE water reducing agent(AEWRA), on the physical properties of concrete to estimate the degree of damage due to over-added chemical agents. For the fresh concrete, slump and slump flow increased with the increase of WRA and AEWRA as expected. Material segregation phenomenon was observed with the over dosage of lignin based AEWRA about 4 times larger than recommended dosage. The over dosage of AE water reducing agent about 4 times larger than recommended dosage resulted in an increase of air contents remarkably. The set retardation occurred greatly with the increase of AEWRA and WRA. For the properties of the hardened concrete corresponding to the over dosage of AEWRA, it is found that compressive strength of over added AEWRA and WRA concrete are much smaller than those of base and recommended dosage concrete proportionally due to associated increasing air content.

• The Korean Journal of Food And Nutrition
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• v.20 no.3
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• pp.289-294
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• 2007

For the purpose of developing a functional yogurt, a new type of yogurt was prepared. To manufacture this new yogurt, 12% skim milk was added to the hot water extract of black soybeans. The yogurt was then evaluated for its acid production(pH and titratable acidity), number of viable cells, viscosity, quality-retention properties, and sensory properties. The titratable acidity of the yogurt with the added 5% black soybean hot-water extract was higher(2.07%) than that of the yogurt without the added extract(1.80%). The viscosity of the yogurt made by adding 5% black soybean hot-water extract was higher(5,040 cps) than that of the yogurt made with only skim milk(2,740 cps). Lactic acid bacteria propagation was stimulated by the addition of the 5% black soybean hot-water extract. When the yogurt prepared with the black soybean hot-water extract was kept at $7^{\circ}C$ for 14 days, its quality-retention was comparatively good. Finally the overall sensory score of the yogurt made with the added 5% black soybean hot-water extract was slightly lower than that of the yogurt made with only skim milk.

• Korean Journal of Materials Research
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• v.27 no.8
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• pp.451-458
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• 2017

The service life of coal gangue concrete(CGC) strongly depends on the capillary water absorption, this water absorption is susceptible to freeze-thaw cycles. In this paper, the cumulative water absorption and sorptivity were obtained to study the effects of 0, 0.5, 1.0, and 1.5 % steel fiber volume fraction added on the water absorption of CGC. Sorptivity and freeze-thaw tests were conducted, and the capillary water absorption was evaluated by the rate of water absorption(sorptivity). Three prediction models for the initial sorptivity of steel fiber reinforced coal gangue concrete(SFRCGC) under freeze-thaw cycles were established to evaluate the capillary water absorption of SFRCGC. Results showed that, without freeze-thaw cycles, the water absorption of CGC decreased when steel fiber at 1.0 % volume fraction was added, however, the water absorption increased with the addition of 0.5 or 1.5 % steel fibers. Once the SFRCGC specimens were exposed to freeze-thaw cycles, the water absorption of SFRCGC significantly increased, and 1.0 % steel fiber in volume fraction added to CGC caused the lowest water absorption, except for the case of the sample without steel fibers added. The CGC with steel fiber at 1.0 % volume fraction performed better. The SFRCGC has a strong response to freeze-thaw cycles. Results also showed that the linear function prediction model is practical in the field of engineering because of its simple form and a relatively high precision. Although the polynomial prediction model presents the highest computation precision among the three models, the complicated form and too many coefficients make it impractical for engineering applications.

• Food Science and Preservation
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• v.10 no.3
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• pp.326-332
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• 2003

Deep seawater is pumped up about 200 m water depth, which has characteristics of rich nutrients, low temperature and cleanness. This study was performed to investigate the effect of deep seawater and deep seawater salt on the yeast growth of fermented bread. The rate of increase in volume of groups added with deep seawater and deep seawater salt was higher than that of groups added with distilled water. The pore pattern of groups added with deep seawater was more regular than that of groups added with distilled water. In sensory property, the bread added with distilled water and deep seawater salt has the highest score (6.56) in overall acceptability.