• Journal of the Korean Home Economics Association
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• v.30 no.3
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• pp.101-117
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• 1992

Effects of gamma irradiation(2.5∼20kGy) on water absorption property was studied for a local variety of black soybeans. In water absorption patterns of black soybeans, the time to reach a fixed moisture content was reduced depending on the increment of water soaking temperature and irradiation dose. Irradiation at 2.5∼10kGy resulted in the reduction of soaking time of black soybeans by about 1∼3 hours and the increase of hydration capacity by 10∼20%, respectively, compared to the nonirradiated control black soybean. The water uptake rate constant of the irradiated black soybean difinitely increased with the increase of dose levels and water soaking temperature. The activation energy for water absorption and z-value were lower in the irradiated black soybeans than in the nonirradiated control black soybean. The efficacy of water absorption property in the irradiated black soybeans was also recognized after one year of storage at room temperature.

• Journal of Environmental Science International
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• v.21 no.10
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• pp.1245-1253
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• 2012

In this study, how branches of Kumho River affect to the water quality on Kumho River was investigated. Water samples from six sampling points at Kumho River and three at each branch were taken from Dec. 2009 to Dec. 2011. As results, Namcheon affected BOD and T-P concentrations on Kumho River while Sincheon did only T-P concentrations. However, the water quality of Kumho River was improved because of Sincheon in terms of BOD and COD concentrations. This was the results from management of Sincheon wastewater treatment facility and Jisan wastewater treatment facility which might be the best example for managing wastewater treatment facilities. Dalsecheon would not affect the water quality of Kumho River although it had bad conditions of water quality because of lack of its water quantity comparing to Kumho River's.

• Journal of Environmental Science International
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• v.5 no.1
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• pp.35-41
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• 1996

For studying of coagulation and sedimentation in estuarine clay, we obtained several flow curves with various concentrations of sea water by using Coutte type rotational rheometer. The initial shear stress on high concentration of sea water was observed big, but after this, its value is decreasing with increasing shear rate. The maximum pick of shear stress is decreasing with the decreasing of concentration of sea water The trend is same totally above for viscosity. The sedimentation times with the concentration of sea water vary in $\infty$ ~ 5 minutes. The zeta potential is changed dramatically between 114 and 118 concentration of sea water. That is consistent with the sedimentation graph. From these results, the phenomena of coagulation and sedimentation can be explained with viscoelastic terms on structual formation among particles by the changes of surface potential affected from contacting sea water to dispersed particles.

• Journal of Environmental Science International
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• v.16 no.11
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• pp.1295-1300
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• 2007

The antibacterial effects of anodic electrolyzed water against various bacteria were studied in this investigation. Complete inactivation of Gram-positive and Gram-negative bacteria occurred within 15 s after exposure to anodic electrolyzed water. Moreover, 1/2, 1/5 and 1/10 diluted anodic electrolyzed water by adding deionized water showed strong antibacterial effects. However, the inhibitory effect of anodic electrolyzed water on the anaerobe of Propionibacterium acnes was much weaker than that on the aerobes, including Gram-positive and Gram-negative bacteria. The degraded fragments of E. coli cell were observed upon treating anodic electrolyzed water for 1 min by using scanning electron microscopy.

• Journal of Korean Society of Water and Wastewater
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• v.19 no.2
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• pp.181-192
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• 2005

This study evaluated the effect of factors influencing the initial biofilm formation in drinking water distribution pipe by running experiments using a $2^{4-1}$ fractional factorial experimental design with a replicate. Important variables used for assessing biofilm formation included BDOC(biodegradable dissolved organic carbon), viable heterotrophic bacteria present in drinking water, water temperature, and shear stress at two levels each. Based on the statistical analysis of biofilm levels measured as attached HPC(heterotrophic plate count) and community-level assay, the main factors that have significant effects on biofilm formation were found to be viable heterotrophic bacteria and BDOC. Water temperature only exhibited significant effect on the levels of attached HPC, while shear stress was not a significant factor under given conditions. Moreover, the statistical analysis revealed that interactions between the important variables were not statistically significant at a 0.05 significance level.

• Elastomers and Composites
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• v.55 no.4
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• pp.314-320
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• 2020

This study focused on experiments with polyethylene glycol (PEG) and glycidyl methacrylate (GMA), which are functional additives for water-expandable rubber. Polychloroprene rubber (CR)/superabsorbent polymer (SAP) composites were prepared and their cure behaviors, mechanical properties, water absorption rates, and surface morphology were measured based on the functional additives applied. When PEG and GMA were applied to the composites, the water absorption rate increased-including the initial rate-compared to that measured when functional additives were not used. The results also show that PEG has a hydrophilic functional group, which allows it to absorb more water, and GMA acts as a coupling agent between CR and SAP. However, with the introduction of functional additives, the cure rate slowed down and the mechanical properties also decreased.

• Journal of Environmental Impact Assessment
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• v.9 no.2
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• pp.99-107
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• 2000

In order to solve water quality problem of domestic dam reservoir, many projects have been performed in a point of view to restoration of water quality. This study was carried out to evaluate the effect of release from sediment on water quality and release characteristics. Daecheong dam reservoir was investigated for two years, from 1998 to 1999. The nutrient release rates of Daecheong reservoir is less than foreign eutrophic reservoir at anoxic condition. For the evaluation of the effect of nutrient release on water quality, internal and external loading was calculated at Daecheong reservoir. As total phosphorus loading from sediment is calculated 9.3 ton/yr and inflow loading from Daecheong reservoir watershed 118 ton/yr, internal loading shows the portion of 7.88% to external loading. At this study, because sampling point was choosed at the point where much sediment is accumulated, experimental result is more than average release rates. Because Daecheong reservoir shows complete thermal stratification and anoxic condition below 30m from water surface in summer seasons, released phosphorus from sediment can not transfer to epilimnion and eventually resettles. Therefore sediment has insignificant impacts on water quality on Daecheong dam reservoir.

• Journal of the Korean Society of Tobacco Science
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• v.4 no.2
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• pp.3-10
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• 1982

This experiment was conducted to study the effect of soil water potenial on the growth and internal changes of stressed plants. The experimental imposition of soil water potential ( $\Psi$soil) were -0.1 to -0.2, -0.2 to -0.5, -0.5 to -3.0, -3.0 to -10.0 bar respectively. During water stress all growth rates were depressed, and the most sensitive period to water stress was found to be 10 to 25 days after transplanting. The water potential of leaf was declined rapidly within 12 hours after with holding of water. Nitrate reductase activity was decreased progressively as water deficit was built up in tobacco leaves, but the activity of alpha- amylase and super contents were increased. There were differences in peroxidase isozyme patterns between tile control and water stressed plant. New isozymes started to appear as tobacco leaf water potential decreased.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.223-226
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• 2002

This study is performed to investigate the influence of aggregate factor on the estimation of water content in fresh concrete. According to the results, water content is estimated higher in the case of basalt and granite aggregate than in the case of limestone because absorption water ratio of basalt and granite is large. As the replacement ratio of recycled aggregate increases, water content is estimated higher. But, after correcting absorption water ratio of aggregate, estimated water content is similar to mixture water content. Therefore, it is important to know the absorption water ratio of aggregates accurately, to estimate water content.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.04a
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• pp.515-520
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• 2002

This paper begin a new approach in the water-gate controller using radio communication. The dissertation is on the controllable device development of water-gate in the remote distance from water-gate trough the transceiver by radio communication. The proposed water-gate control device is simple in structure, an suitable for implementation of water-gate control in the remote distance. The remote controller water-gate device inspected the up and down motion of water-gate through the LCD displayer, so that it was very safety driving about the surroundings information, over loading and position of water-gate, and so on.