• Journal of Korea Water Resources Association
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• v.53 no.8
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• pp.605-616
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• 2020

The purpose of this study is to assess the future hydrological and water quality change of Man-gyeong river basin (1,602 ㎢) based on future extreme climate change scenarios and reduction of inter-basin water transfer amount using SWAT (Soil and Water Assessment Tool). The SWAT was calibrated (2012~2014) and validated (2016~2018) at 2 water level observation stations (DC, JJ) and 2 water quality observation stations (SR, GJ) considering inter-basin water transfer amount, stream water withdrawal, and point source data. For the streamflow, the coefficient of determination (R²) was 0.70 and the average Nash-Sutcliffe efficiency (NSE) was 0.51 respectively. For the water quality of SS, T-N, and T-P, the R² was 0.72, 0.80 and 0.72 respectively. The future average streamflow under climate change scenarios increased up to 459 mm/yr, and average SS, T-N and T-P yields also increased up to 19,548 ton/yr, 68,748 kg/yr, and 13,728 kg/yr respectively. When the amount of inter basin water transfer decreased, the streamflow especially decreased in spring and winter periods, and the future water quality yields increased under the influence of precipitation. In order to solve the deterioration of water quality due to decrease in the flow rate and an increase in the load, the amount of inter basin water transfer should be maintained to a certain level.

• Water Engineering Research
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• v.1 no.4
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• pp.259-266
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• 2000

Scour hole is formed due to the high shear stress of the jet flow at the outlet of a hydraulic structure and vortex erosion occurs in the scour hole. It is important to determine the amount of vortex erosion occurs in the scour hole. It is important to determine the amount of vortex erosion for the design of bed protection. If the vortex erosion continues and reaches to the hydraulic structure, it causes the deformation of the structure itself. To obtain the amount of the vortex erosion, it is necessary to determine the shear velocity of the line vortex in the scour hole was derived by the theory of energy conservation and found to be related to the upstream overflow velocity. The amount of vortex erosion from the scour hole was obtained using entrainment equation for given value of shear velocity. For a design purpose, if the flow velocity at the end of an apron and the properties of bed material are given, the amount of vortex erosion was obtained.

• Journal of the Korean Home Economics Association
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• v.8 no.1
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• pp.93-99
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• 1970

To Know the factors required to make best quality of steamed rice with large amount of rice, several organizations that serve meals were surveyed. Factor that mostly influence the amount of water to the amount of rice is a kind or rice. In the case of good quality rice, when the amount of rice is more than 10cups, the ratio of water to rice is 0.9 and that of poor quality rice is 0.7 Average ratio is 0.8 Therefore, ordinarily with the ratio of 0.8, good quality of steamed rice can be made. Washed rice should be used to measured the of rice. To make a good quality of steamed rice with large amount of rice, center part of the boiling rice should be stirred generously several times to equalize the temperature.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.2
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• pp.301-305
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• 2012

The amount of irrigation water can be calculated based on the irrigation schedule in irrigation manual. At present, the maximum irrigation manual, which was developed in 1999 for the maximum yield with maxmum irrigation, is using. Now the water saving irrigation manual for red pepper, without decrease of crop yield, has been developded in 45 areas of korea. Among 45 regions, 9 regions which were selected respectively from 9 Provinces of Korea, were used for this study. The water saving irrigation manual has been used easily without soil sampling and measurement of soil water status. The objective of this study is to assess the possibility of the saving of irrigation water compared to the maximum irrigation manual. The average potential evapo-transpiration (PET) during 30 years in 9 region for the red pepper cultivation was a $2.69mm\;day^{-1}$. The saving amount of irrigation water for red pepper cultivation by saving irrigation manual compared to the maximum irrigation manual in a year was 309.4 mm, 303.3 mm and 309.5 mm in the soil of Sandy Loam (SL), Loam (L) and Silty Loam (SiL), respectively. The average saving amount of irrigation water for red pepper cultivation by saving irrigation manual compared to the maximum irrigation manual in a year was 307.4 mm.

• Journal of the Korean Society of Clothing and Textiles
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• v.5 no.1
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• pp.9-14
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• 1981

The influence of laundering conditions on calcium deposition on the fabric was studied by repeated laundering the cotton fabric with soap in the hard water of 200 P.P.M. $CaCO_3$. The experimental variables were: 1) soap concentrations ($0.06\%$, $0.13\%$, $0.25\%$), 2) water contents in the fabric after hydroextraction. ($65\%$, $150\%$, $315\%$), 3) builders (Na-EDTA, sodium carbonate, sodium metasilicate), 4) washing cycle (5, 10, 15, 20 cycles). The fabric was washed for 15 minutes at $23\pm1^{\circ}C$ in a washing machine (Model; Gold Star Wp-2005) under the similar conditions with those of home laundering, and rinsed 5 times for 5 minutes. The amount of calcium deposits on the fabric was determined by the EDTA-Back titration method described by Wasserman and Basch. Results of this study were follows: 1) The amount of calcium deposits on the fabric increased with increasing wash cycles. 2) During the rinsing process, residual calcium content on the fabric increased with water content in the fabric after hydroextraction. 3) The amount of calcium deposits on the fabric decreased with the increasing soap concentration above the equivalent amount of calcium ion content in the water. 4) Sequestering agents and alkaline builders influenced the amount of calcium deposits on the fabric. The amount of calcium deposits on the fabric was in the order of sodium metasilicate, sodium carbonate, nonbuilder, and EDTA.

• Environmental and Resource Economics Review
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• v.14 no.2
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• pp.475-491
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• 2005

This study reviews various problems associated with the method of estimating the demand for industrial water that was employed in the Water Vision 2020 and it suggests an alternative econometric method. Comparing with the data cited in the Report on Industrial Census, estimates obtained by employing the concept of demand function are more exact compared to those offered by the Water Vision 2020. The amount of industrial water in 1998 was estimated at 2.8 billion tons decreasing by 2003. By employing the concept of demand function, this study shows that the amount of industrial water was 2.1 billion tons in 2003 while according to the Water Vision 2020 it amounted to 3.3 billion tons in 2001. Thus, it appears that the amount of industrial water in the Water Vision 2020 has been overestimated. This study also shows that the industrial water demand can be controlled by means of certain pricing policies. Finally, we argue that the demand for industrial water should be estimated by taking account of economic variables such as water price and output.

• The Korean Journal of Pesticide Science
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• v.8 no.1
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• pp.38-45
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• 2004

To elucidate the photolysis characteristics of the insecticide imidacloprid in the environment, $[^{14}C]$imidacloprid was treated into water and paddy soil-water system. In water system, the amount of $^{14}C$-radioactivity distributed in aqueous phase was rapidly increased up to 80% of total $^{14}C$ in water during 7 days of exposure to sunlight. Also, the amounts of imidacloprid in water at day 0 and 3 days after treatment were 1.2461 and 0.8594 mg/kg, respectively, not being detected 7 days after treatment, indicating rapid degradation of imidacloprid in water by sunlight. One photodegradation product, imidacloprid urea, in which the $N-NO_2$ moiety of imidacloprid was replaced by oxygen, was detected from water in water and water-paddy systems. The amount of the metabolite detected from water in water system was 0.0112 mg/kg 1 day after treatment and reached the top concentration of 0.0391 mg/kg 7 days after treatment. In case of water-paddy system, its amount was 0.0117 mg/kg 1 day after treatment and reached the highest concentration of 0.0259 mg/kg 3 days after treatment. Rapid transformation of imidacloprid into polar compounds continued until 7 days after treatment, considering that 80% of $^{14}C$ in water distributed in aqueous phase 7 days after treatment, amount of imidacloprid was 1.6538 mg/kg at day 0 and 0.8785 mg/kg 1 day after treatment, not being detected after 15 days, indicating rapid degradation of imidacloprid in water-paddy soil system by sunlight. The direct degradation of imidacloprid to imidacloprid urea would be a major photodegradation pathway in water and water-paddy soil systems.

• Journal of the East Asian Society of Dietary Life
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• v.8 no.2
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• pp.173-180
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• 1998

This study was conducted to examine the sensory quality, the degree of gelatization, pH, color, texture and moisture content of paeksolgi with omija water extracts added. The results of the analysis were as follows : The moisture contents of Paeksolgi were about 36~39%. The L value of the control group was 83.04 The degree of the colour was (L value: 71.82~86.56), (a value: -1.33~+0.78), (b value : 7.84~9.78). As the amount of omija water extracts was increased. the L and a values increased, but the b value showed a similar value, It was found that the yellowness decreases by increasing the soaking time of each type. The gelatinization of Paeksolgi with omija water extracts added was decreased as the amount of omija was increased. The sensory quality of paeksolgi with 5~7% omija water extracts added showed the most favorable sensory evaluation. In view of color, after taste and overall quality, the D$_2$group of Paeksolgi was preferable to the other paeksolgi groups with omija water extracts added.

• Journal of Korean Society of Water and Wastewater
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• v.18 no.4
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• pp.470-479
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• 2004

The experimental conditions and relationships between parameters such as organic matter, aeration volume, aeration time, and precipitation time for the effective treatment of domestic wastewater were investigated. With the batch systems, the adsorption amount of unit microbe was measured with the change of MLSS concentration, precipitation time, and aeration amount. Theoretical adsorption amount of microbes was then numerically formulated by use of a SPSS multiple analysis as follows: $$Y=-0.0106(X_1)+0.07310(X_2)+42.705(X_3)+62.700$$ In this study, the amount of organisms to be removed in the range of MLSS concentration 2,000~4,500 mg/l were examined. In order to investigate the optimal condition of nitrification, the upper water in the biosorption stage was used as the initial experiment water. The results showed that the C/N ratio was 1.5 and the reaction time for the optimal nitrification was 1.5 hr. When the adsorption efficiency for microbe biosorption was 66%, the optimum denitrification efficiency was 83.3%. When the optimum parameters obtained from the batch experiment were applied to the lab-scale operation, the total retention time from the flow-in to flow-out was 10 hours and the removal efficiency was 93.8% for $COD_{cr}$ and 80.9% for TN. For the full-scale operation, the total retention time was 9.0 hours and the removal efficiency was 94.4% for BOD, 89.6% for $COD_{cr}$, 88.0% for TN, and 86.2% for TP.

• Textile Coloration and Finishing
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• v.13 no.2
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• pp.128-134
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• 2001

Following the prior studs regarding that 1.0g of cotton fabric round be dyed uniformly with a reactive dye in the solvent mixture of $2m\ell$ of water and $23m\ell$ of dichloromethane, silk fabric was dyed with C. I. Reactive Blue 203 in the water/dichloromethane two-phase immiscible solvent media. In order to minimize dye loss due to its hydrolysis, the reactive dyeing was carried out in dichloromethane containing a small amount of water. With only $3m\ell$ of water in $22m\ell$ of dichloromethane, 1.0g of silk fabric could be dyed perfectly. The uptake ratio was increased greatly, compared wish that of normal reactive dyeing in a water medium. It would seem that the one of hydrophobic solvents, dichloromethane, can assist the Even dyeing as it disperses a small amount of dye-dissolved phase and conveys this water phase to the fabric entirely and uniformly.