• Applied Chemistry for Engineering
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• v.5 no.4
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• pp.706-713
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• 1994

Isothermal vapor-Liquid equilibrium data have been measured for binary systems MTBE-methanol, MTBE-n-heptane, and methanol-n-heptane at $45^{\circ}C$ and $65^{\circ}C$ by using head space gas chromato-graphy (H.S.G.C). Among these systems a minimum azeotrope was observed in both of MTBE-methanol system and n-heptane-methanol system. Particularly n-heptane-methanol system has a heterogeneous minimum azotrope since it has an immisible region. These equilibrium data were correlated with the excess Gibbs energy model, and the thermodynamic consistency test was also carried out by using Redlich-Kister equation.

• Journal of Korea Multimedia Society
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• v.4 no.2
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• pp.136-144
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• 2001

visual cryptography is a simple method in which secret information can be directly decoded in human visual system without any cryptographic computations. This scheme is a kind of secret sharing scheme in which secret of image type is distributed to n random image(we call it share). When the secret image is distributed to n shares, the original pixel is expanded as much as the size of column in basis matrix. It causes the deterioration of contrast in docoded secret image. Therefore, many researches have performed to reduce the size of pixel expansion and to improve the contrast by overlapping the row in basis matrix for (k, n) visual cryptography. In addition, we show that the proposed method can construct the (k, n) visual cryptography with multiple contrasts depending on selecting k out of n slides in a group.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.9
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• pp.796-800
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• 2000

Bi$_2$Sr$_2$Ca$_{n}$Cu$_{n+1}$ O$_{y}$(n$\geq$0; BSCCO) thin film is fabricated via two different processes using an ion beam sputtering method i.e. co-deposition and layer-by-layer deposition. A single phase of Bi2212 can be fabricated via the co-deposition process. While it cannot be obtained by the layer-by-layer process. Ultra-low growth rate in our ion beam sputtering system brings out the difference in Bi element adsorption between the two processes and results in only 30% adsorption against total incident Bi amount by layer-by-layer deposition, in contrast to enough Bi adsorption by co-deposition.on.n.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.230-234
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• 2000

Bi$_2$Sr$_2$Ca$_{n}$Cu$_{n+1}$ O$_{y}$(n$\geq$0; BSCCO)thin film is fabricated via two different processes using an ion beam sputtering method i.e. co-deposition and layer-by-layer deposition. A single phase of Bi2212 can be fabricated via the co-deposition process. While it cannot be obtained by the layer-by-layer process. Ultra-law growth rate in our ion beam sputtering system brings out the difference in Bi element adsorption between the two processes and results in only 30% adsorption against total incident Bi amount by layer-by-layer deposition, in contrast to enough Bi adsorption by co-deposition.on.n.

• Journal of Korean Medicine Rehabilitation
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• v.24 no.2
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• pp.51-64
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• 2014

Objectives This study was carried out to know the effects of Keonbodan (hereinafter referred to KBD) in osteoarthritis induced by Monosodium iodoacetate(hereinafter referred to MIA) on Wistar rat. Methods Osteoarthritis was induced by injection of MIA into left knee joint cavities of rat. Osteoarthritis rats were divided into 4 groups (normal (n=6), control (n=6), indomethacin (n=6), KBD (n=6) group). The control group was administered normal saline and indomethacin group was administered indomethacin (2 mg/kg). And the KBD group was administered KBD (142 mg/kg). Each groups were administered by orally for 4 weeks. This experiment were carried out in vivo. In vivo, at the end of the experiment (5 weeks after MIA injection), effects on hepatotoxicity and nephrotoxicity, cytokines in serum, arachidonic acid, osteocalcin, MMP-9, TIMP-1 and cartilage volume were evaluated. And histopathological examinations on the articular structures of knee joints were performed. Results 1. In weight-bearing measurement, level of weight was increased. 2. In order to hepatotoxicity and nephrotoxicity, ALT, AST, BUN and creatinine were tested. And there were no significant changes. 3. In serum, levels of TNF-$\alpha$, IL-$1{\beta}$ were significantly decreased. IL-6 was insignificantly decreased. 4. In serum, level of MMP-9 and TIMP-1 was decreased. 5. In serum, level of $LTB_4$, $PGE_2$ and osteocalcin was decreased. 6. In ${\mu}$CT-arthrography, the cartilage volume was greater than that of the control group. 7. The joint damage induced by osteoarthritis was lesser than the control group in histopathologic observation (H&E, Safranin-O staining). Conclusions These results demonstrated that KBD suppressed the osteoarthritis- inducing effects of MIA in rat. And further studies are required to find out more effective substance and anti-osteoarthritic mechanism in the future.

• Analytical Science and Technology
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• v.6 no.3
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• pp.307-311
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• 1993

Ionophore, which contains 5-membered heterocyclic compound, was prepared. $Mg^{2+}$ was determined by salting-out technique using ionophore as a chelating reagent. After $Mg^{2+}$ was extracted into the acetonitrile layer as a Mg-$(Ionophore)_2$ complex from acetate buffered aqueous solution by salting-out extraction technique, absorbance of complex was recorded by atomic absorption spectrophotometry. Optimum pH was between 2.5 and 5.0 for extraction and 1:2([$Mg^{2+}$]/[ionophore]) complex were formed. The range of detection was 0.24ppm~2.4ppm and $Ca^{2+}$ and EDTA were interfered in the determination of $Mg^{2+}$.

• The Korean Journal of Food And Nutrition
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• v.30 no.1
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• pp.166-174
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• 2017

The purpose of this study was to compare dietary self-efficacy for sodium intake reduction and dietary behaviors by eating areas. Subjects (797 males and 767 females) were classified according to perceived dietary habit levels related to sodium intake (lowest: ${\leq}10$ (n=434), low: $11{\sim}{\leq}13$ (n=471), high: $14{\sim}{\leq}15$ (n=360), highest: $16{\leq}$ (n=299)) using an online survey with a sample that was geographically representative of the population. The highest group was significantly younger and had a higher student proportion than the lowest group. Dining contexts regarding home led to a significantly higher sodium intake in the highest group, but it was eating out for the lowest group. The highest group had a significantly lower intention to reduce sodium intake compared to the lowest group. In the home cooked meals, the highest group displayed a significantly lower cooking frequency, less effort with respect to a low sodium diet and cooking habits related to sodium intake as compared to the lowest group. Also, regarding eating out and food service, the highest group exhibited significantly lower efforts and dietary behaviors to reduce sodium intake than the lowest group. The dietary score for sodium reduction behavior in the highest group was significantly lower compared to the lowest group, for home cooked meals, eating out, as well as food service. Thus, dietary guidelines and nutrition education for the reduction of sodium intake by eating areas need to be developed and provided.

• The Journal of Korean Physical Therapy
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• v.14 no.4
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• pp.100-118
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• 2002

This study was to investigate the effect of long-term high intensity endurance training on the activation of antioxidation enzyme activity, lipid peroxidation and lipoprotein metabolism. 15 subjects were divided into, endurance exercise + antioxidation Vitamin supplement(n=5), endurance exercise(n=5), and the control(n=5) groups. The endurance exercise groups(endurance exercise + antioxidation Vitamin supplement and endurance exercise) had 12 week of endurance exercise program. The antioxidation Vitamin supplement group was taken a Vitamin C tablet with 1000mg/day and Vitamin E tablet with 671.14mg/day right after lunch. The results obtained from this study were as follows; 1. Looking at the changes of SOD, Endurance exercise+antioxidation Vitamin supplement group and endurance exercise groups showed the significantly greater decrease in the activation of SOD after 12 weeks of all-out exercise. 2. Looking at the changes of CAT, Endurance exercise+antioxidation Vitamin supplement group revealed subjects tended to increase CAT after all-out exercise although statistically non-significant. Endurance exercise+antioxidation Vitamin supplement group showed the significantly greater increase in the activation of CAT after 12 weeks treatment for all-out exercise. 3. Looking at the changes of GPX, Endurance exercise+antioxidation Vitamin supplement group revealed subjects tended to increase GPX for the rest and after all-out exercise although statistically non-significant. Endurance exercise+antioxidation Vitamin supplement group showed the significantly greater increase in the activation of GPX after 12 weeks treatment for all-out exercise. 4. The MDA change showed the significant decrease after 6 weeks, after 12 weeks for the all-out exercise of Endurance exercise + antioxidation Vitamin supplement group. 5. There was non-significant change in lipoprotein metabolism for the rest and after all-out exercise.

• Journal of the Korean Geosynthetics Society
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• v.17 no.4
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• pp.213-224
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• 2018

In this study, a series of accelerated creep tests (SIM) was carried out on geosynthetic strip reinforcements with folding grooves having different tensile strengths (15 kN, 25 kN, 35 kN, 50 kN, 70 kN, and 90 kN) to analyze creep characteristics and to assess creep reduction factors. In particular, long-term creep tests were conducted on geosynthetic strip reinforcements with 25 kN tensile strength, which is widely used, to compare and analyze the accelerated creep test results. As a result, the creep reduction factor increased with an increasing design life of reinforcement. In addition, geosynthetic strip reinforcement using the same material and manufacturing method showed similar creep reduction factors at the same design life for different tensile strengths. When both long-term and accelerated creep test data were used, the creep reduction factors from the accelerated test were estimated to be 5.9%~7.1% less than those from the long-term creep test for the design life ranging from 50 to 100 years.

• Journal of the Korean Chemical Society
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• v.40 no.3
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• pp.167-172
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• 1996

For the preparation of single-crystalline GaN film, heteroepitaxial growth on a sapphire substrate was carried out by halide vapor phase epitaxy(HVPE) method. The resulting GaN films showed n-type conductivity. The insulator type GaN film was made by doping with Zn(acceptor dopant), which showed emission peaks around 2.64 and 2.43 eV. The result of this study indicates that GaN can be obtained in an epitaxial structure of MIS(metal-insulator-semiconductor) junction. The observed data are regarded as fundamental in developing GaN epitaxial films for light emitting devices of hetero-structure type.