• Korean Journal of Environmental Agriculture
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• v.26 no.3
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• pp.197-203
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• 2007

Zerovalent iron (ZVI) has been widely used in the removal of environmental contaminants from water. The objective of this research was to assess the efficiency of ZVI for immobilization of As (V) in the contaminated water under various chemical conditions. Batch-type experiments showed that the immobilization process followed a first-order kinetic model. Rate constant (k) of the reaction increased consistently and proportionally as increasing ZVI concentrations from 1% (0.158 $hr^{-1}$) to 3% (0.342 $hr^{-1}$), and temperatures from $15^{\circ}C$ (0.117 $hr^{-1}$) to $35^{\circ}C$ (0.246 $hr^{-1}$), respectively. Whereas the rate constant decreased as increasing As (V) concentrations from 1 mg $\Gamma^{-1}$ (0.284 $hr^{-1}$) to 3 mg $\Gamma^{-1}$ (0.153 $hr^{-1}$), and the initial pH from 3 (0.393 $hr^{-1}$) to 9 (0.067 $hr^{-1}$), respectively. Results demonstrated that As (V) in an aqueous solution was rapidly immobilized by ZVI treatments. Zerovalent iron was fast method for remediation of As (V) contaminated water.

• Food Science and Preservation
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• v.23 no.6
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• pp.859-865
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• 2016

Thise study aimed to determine the optimum antioxidant extraction conditions of dried Gugija (Lycium chinensis Mill). To determine the operational parameters, including ethanol concentration ($X_1$, 0~80%) and extraction time ($X_2$, 1~5 hr), a response surface methodology was applied to monitor brown color intensity, total phenolic compounds, ABTS radical scavenging activity, and $Fe^{2+}$ chelating activity. Coefficients of determinations ($R^2$) of the models were 0.8486~0.9214 (p<0.05~0.1) in dependent parameters. Brown color intensity of Gugija extracts reached a maximum of 0.75 (OD in 420 nm) under extraction conditions of 2.88 hr in 78.10% ethanol. Total phenolic compounds reached a maximum of $2,355{\mu}g$ under extraction conditions of 4.94 hr in 30.17% ethanol. ABTS radical scavenging activity was 13.83% at 4.61 hr and 16.21% ethanol. $Fe^{2+}$ chelating activity showed a maximum of 58.54% under extraction conditions of 3.39 hr in 0.76% ethanol. Optimum extraction conditions (5 hr extraction in 15% ethanol) were obtained by superimposing the contour maps with regards to total phenolic compounds, ABTS radical scavenging activity, and $Fe^{2+}$ chelating activity of dried Gugija. Maximum values of total phenolic compounds, ABTS radical scavenging activity, and $Fe^{2+}$ chelating activity under optimum extraction condition were $2,397{\mu}g$, 15.62% and 54.78%, respectively.

• Korean Journal of Agricultural Science
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• v.39 no.4
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• pp.459-466
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• 2012

The objective of this study is to observe growth pattern of grand rapids(lettuce) according to different dexperimental conditions for minimizing its growth period such as composition of nutrient, irradiation time of light source and cultivation mode. The culture of water spray type using seeds of grand rapids was performed during growth period of total 50 days. Experimental conditions consist of five compositions of nutrient (PW 0.5 mS/cm, PW 1.0 mS/cm, PY 0.5 mS/cm, PY 1.0 mS/cm, PW 2.0 mS/cm) and three irradiation times of light source (12h(on) / 12h(off), 18h(on) / 06h(off), 24h(on) / 00h(off)). Illumination was adjusted to ratio of 7:1:1 of red, blue and white color, respectively. Indoor environmental condition for cultivating grand rapids is as follows: temperature (19-$22^{\circ}C$), relative humidity (60-70%) and carbon dioxide (1,000-1,200 ppm). The data were obtained from five iteration tests. The maximum growth level was observed in the experimental condition of 18 hr(on) / 06 hr(off) and PY 1 mS/cm for 1st week of cultivation period, 24 hr(on) / 00 hr(off) and PY 1mS/cm for 2nd week of cultivation period, and 24 hr(on) / 00hr(off) and PW 1 mS/cm for 3rd week of cultivation period, respectively. On the contrary, the minimum growth level was observed in the experimental condition of 18 hr(on) / 06 hr(off) and PW 0.5 mS/cm for 1st week of cultivation period, 12 hr(on) / 12 hr(off) and PW 0.5 mS/cm for 2nd week of cultivation period, and 12 hr(on) / 12 hr(off) and PY 0.5 mS/cm for 3rd week of cultivation period, respectively. Based on the results obtained from this study, it is concluded that the growth level of grand rapids varied with different irradiation time of light source and composition ratio of nutrient according to cultivation period.

• Korean Journal of Clinical Pharmacy
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• v.8 no.1
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• pp.13-18
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• 1998

The purpose of this study was to determine pharmacokinetic parameters of vancomycin using the compartment model dependent and compartment model independent analysis in 6 Korean normal volunteers and 8 ovarian cancer patients. Vancomycin was administered 1.0 g bolus by IV infusion over 60 minutes. The elimination rate constant ($\beta$), volume of distribution (Vd), total body clearance (CLt), and area under the plasma level-time curve (AUC) of vancomycin in normal volunteers using the compartment model dependent analysis were $0.150\pm0.030\;hr^{-1},\;32.9\pm2.81\;L/kg,\;5.36\pm0.63\;L/hr,\;and\;186.5\pm20.5\;{\mu}g/ml{\cdot}hr$, respectively. The $\beta$, Vd, CLt, and AUC of vancomycin in ovarian cancer patients using the compartment model dependent analysis were $0.109\;0.008\;hr^{-1},\;41.5\pm3.01\;L/kg,\;4.58\pm0.57\;L/hr\;and\;218.3\pm22.9\;{\mu}g/ml{\cdot}hr$, respectively. There were significant differences (p<0.05,\;p<0.01) in $\beta$, Vd, CLt, and AUC between normal volunteers and ovarian cancer patients. The elimination rate constant (Kel), CLt, and AUC of vancomycin in normal volunteers using the compartment model independent analysis were $0.152\pm0.022\;hr^{-1},\;5.77\pm0.75\;L/hr,\;and\;173.2\pm22.5;{\mu}g/ml{\cdot}hr$, respectively. The Kel, CLt, and AUC of vancomycin in ovarian cancer patients using the compartment model independent analysis were $0.126\pm0.012\;hr^{-1},\;4.96\pm0.55\;L/hr,\;and\;201.7\pm25.6;{\mu}g/ml{\cdot}hr$, respectively. There were significant differences (p<0.05, p<0.01) in Kel, CLt, and AUC between normal volunteers and ovarian cancer patients. And also, there was significant difference (p<0.05) in Kel of vancomycin in ovarian cancer patients between the compartment model dependent and independen analysis. It is necessary for effective dosage regimen of vancomycin in ovarian cancer patient to use these population parameters.

• Microbiology and Biotechnology Letters
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• v.31 no.4
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• pp.377-382
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• 2003

Purification of methioninase resulted in a yield of 69%, and SDS-PAGE analysis of the purified product revealed a single band of approximately 43 kDa in molecular weight. in vitro experiments with cancer cells incubated in methionine-free media demonstrated an increase in $^{11}$ C-methionine uptake to 25.8$\pm$1.1% at 6 hr, 31.8$\pm$0.8% at 24 hr, and 62.2$\pm$0.6% at 48hr, compared to controls. Treatment of the cancer cells with purified methioninase showed no decrease in survival after a 2 hr incubation with 0.01 U/ml, but survival of RR1022 cells decreased 30% after 24 to 48 hr incubation. SKOV-3 cells showed a 5% and 14% decrease in survival with 0.1 and 1 U/ml methioninase after 24 hr. After 48hr survival decreased 15% and 24% with 0.1 and 1 U/ml methioninase. Measurements of $^{11}$ C-methionine uptake in RR1022 cells demonstrated no change at 2 hr, but a 13.7$\pm$4.7% and 40.7$\pm$2.6% increase in uptake at 24 and 48 hr, respectively. SKOV-3 cells also showed no change at 2 hr, but had a 17.7$\pm$7.2% and 38.9$\pm$4.9% increase in $^{11}$ C-methionine uptake after 24 hr and 48 hr treatment with methioninase, respectively. $^{11}$ C-methionine PET imaging revealed clear visualization of both the tumors and contralateral infectious lesions. Administration of rMET appeared to result in a slight increase in tumor:nontumor contrast on $^{11}$ C-methionine PET images. Injection of purified methioninase also produced PET images where tumor uptake was higher than that of infectious lesions.

• Journal of Korea Water Resources Association
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• v.31 no.3
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• pp.317-326
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• 1998

Water consumption characteristics on the northern part of Seoul were analyzed using wavelet transform with a base function of Coiflets 5. It turns out that long term evolution mode detected at 212 scale in 1995 was in a shape of hyperbolic tangent over the entire period due to the development of Sanggae resident site. Furthermore, there was seasonal water demand having something to do with economic cycle which reached its peak at the ends of June and December. The amount of this additional consumption was about $1,700\;\textrm{cm}^3/hr$ on June and $500\;\textrm{cm}^3/hr$ on December. It was also shown that the periods of energy containing sinusoidal component were 3.13 day, 33.33 hr, 23.98 hr and 12 hr, respectively, and the amplitude of 23.98 hr component was the most humongous. The components of relatively short frequency detected at $2^i$[i = 1,2,…12] scale were following Gaussian PDF. The most reliable predictive models are multiple AR[32,16,23] and ARMA[20, 16, 10, 23] which the input of temperature from the view point of minimized predictive error, mutual independence or residuals and the availableness of reliable meteorological data. The predicted values of water supply were quite consistent with the measured data which cast a possibility of the deployment of the predictive model developed in this study for the optimal management of water supply facilities.

• Journal of vocational education research
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• v.36 no.2
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• pp.68-94
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• 2017

The purpose of this study is to provide basic data for the development of school education and employment policy by analyzing the differences between image of meister high school students anticipated by industrial HR managers and image actually perceived. For this, semantic differential method developed by Osgood (1957) was selected as the study tool. To find out images of meister high school students, validity of 50 adjectives suggested by Osgood and 21 additional adjectives used in previous studies was reviewed by 10 experts. Final 20 adjectives were selected by excluding adjectives that fail to satisfy validity of contents. Proportional sampling in metropolitan and non-metropolitan areas was done to select 350 final survey samples. A total of 600 surveys were distributed and 230 were returned. Return rate was 38.3%. The results of this study are as follows. First, image of meister high school students anticipated by industrial HR managers showed average score of 2.49, which indicates a positive image. In addition, factor analysis was performed to classify adjectives into groups, and they were divided into three factors including external factor, way of thinking factor, and internal (personality) factor. Second, image of meister high school students currently perceived by industrial HR managers showed average score of 3.24, which indicates a positive image. Third, image of meister high school students currently perceived by industrial HR managers was not as positive as image they anticipate.

• Journal of Korea Water Resources Association
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• v.55 no.11
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• pp.969-977
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• 2022

In order to respond to the increase in water disasters due to climate change and urbanization, research on low impact development (LID) techniques and application to cities are expanding. The LID technique is a technology that reduces rainwater runoff in the city, controls various water disasters such as flash floods, etc. in an eco-friendly way, and restores the urban water circulation system to a natural water circulation system. However, quantitative analysis of stormwater runoff reduction through the LID technique is insufficient. Therefore, this study analyzed the ratio of the permeable area required to reduce the surface runoff of rainfall (25 mm/hr, 50 mm/hr, 100 mm/hr) with respect to the impervious watershed area of the old city using the permeable pavement. As a result of the analysis, it was found that a permeable area ratio of 7.14 to 12.63% of the total area was required for 25 mm/hr, 15.79 to 26.97% for 50 mm/hr, and 30 to 55.81% for 100 mm/hr.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.134-137
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• 2003

Acaricide effect against Tetranichus urticae, Myzus persica, Spodoptera litura and Plutella xylostella with the Ginkgo biloba leaves extracts was reviewed. This result was motality 74.3%, 88.7% respectively, after tretment 24hr, 72hr about $80^{\circ}C$ water extract(GLW80, 1%) of Tetranichus urticae and the insecticide took effect showed its effect in some 50% against the other three. But, motality of Tetranichus urticae against 10% GLW80 showed its 90.6%, 98.3% after tretment 24hr and 48hr.

• Korean Journal of Optics and Photonics
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• v.4 no.4
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• pp.487-492
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• 1993

A polarization maintaining fiber optic gyroscope was constructed having an optical loss of about 25 dB. Using the earth rotation rate as a reference, the long term stability of better than $3^{\circ}/hr$ and the rms short term noise of $0.6^{\circ}/hr/{\sqrt{Hz}}$ were obtained.