• Journal of Korea Water Resources Association
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• v.47 no.10
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• pp.973-983
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• 2014

This study focused on the selection of appropriate plant species of VFS (vegetative fiter strips) and the assessment of VFS effects for reducing NPS (non-point source) pollution from uplands. The experimental field was constructed with 1 control and 6 treated plots in the upland area of $1,500m^2$ with 5% slope which is located in Gunwi-gun, Gyeongbuk province. Six vegetation including Chufa, Common crabgrass, Barnyard grass, Turf grass, Tall fescue, Kenturky bluegrass, were applied to install VFS systems during the study period from June 2011 to Dec. 2012. The results of this study showed that 6.1~77.8% in runoff and 15.6~90.3% in TS, 49.9~96.6% in T-P, and 6.7~91.1% in T-N were reduced from the VFS treated plots. Generally high reduction effects were observed from TS, T-P, T-N, and SS, while BOD, TOC, and $NO_3^-$ showed low reductions. The best vegetation type was Turf grass showing higher reduction effects of NPS pollutions and having relatively easier maintenance efforts compared to other vegetations selected in this study. Based on these results, VFS technique found to be an effective management practice for reducing agricultural NPS pollutions in Korean upland conditions. Further study needs to be performed through various field experiments with long term monitoring in order to develop a design manual of VFS system for practical applications.

• Journal of the Korean Applied Science and Technology
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• v.37 no.5
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• pp.1366-1377
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• 2020

The purpose of this study was to confirm the effect of the Havruta-based teaching and learning method on the academic self-efficacy, critical thinking tendency, learning satisfaction, and academic stress of nursing students. This study was conducted with 90 2nd graders of nursing department with one-group pretest-posttest design. The Havruta-based instructional design consists of five stages: the 1 stage is the pre-learning stage, the 2 stage is the introduction and development stage, the 3 stage is the organization of the class content, the 4 stage is the question and teaching stage, and the 5 stage is organized and integrated. Four weeks of Havruta-based teaching and learning method was applied. The data were analyzed by SPSS 25.0. The general characteristics of the subjects were frequency and percentage, and The dependent variable for measuring the effect of experimental treatment was analyzed by paired t-test. As a result of the study, the application of the Havruta-based teaching and learning method showed statistically significant results on academic self-efficacy(t=-3.711, p<.000), learning satisfaction(t=-2.580, p=.012), and academic stress(t=6.500, p<.000). The Havruta-based teaching and learning method has been confirmed to be an effective teaching method that increases the subject's academic self-efficacy, learning satisfaction, and lowers academic stress, so it can be applied to other major subjects in the future.

• Journal of Life Science
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• v.29 no.2
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• pp.209-214
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• 2019

Sargassum horneri (Turner) C. Agardh is a marine brown algae widely distributed in the North Pacific Ocean. It is known for its anti-inflammatory and anti-atopic effects. In this study, we determined the effects of ethanol extract of Sargassum horneri (Turner) C. Agardh (EESH) on anti-obesity activities in 3T3-L1 preadipocytes. Our results indicated that treatment with EESH decreased the differentiation of 3T3-L1 preadipocytes in a dose-dependent manner, as confirmed by a decrease in lipid droplet content observed by oil red O staining. The concentrations of cellular triglycerides were also reduced in 3T3-L1 cells after treatment with EESH. Triglyceride content was inhibited by 13%, 16%, and 23% after treatment with 250, 500, and $1,000{\mu}g/ml$ of EESH in 3T3-L1 cells, respectively. Western blotting analysis showed that EESH suppressed adipogenic transcription factor expression in a dose dependent manner. Specifically, it suppressed cytidine-cytidine-adinosine-adenosine-thymidine (CCAAT) /enhancer binding proteins $(C/EBP){\alpha}$, $C/EBP{\beta}$ and peroxisome proliferator-activated receptor $(PPAR){\gamma}$. This indicated that EESH could control the expression of adipogenic transcription factors and inhibit the differentiation of adipocytes. Taken together, these findings demonstrated that EESH showed anti-obesity effects and could have potential uses in the field of nutraceuticals.

• Journal of the Korean Ceramic Society
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• v.27 no.7
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• pp.943-951
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• 1990

Steady-state sublimation vapour pressures of anhydrous bismuth triiodide have been measured by the continuous gravimetric Kundsen-effusion method from 430.0 to 558.9 K and equilibrium sublimation pressures were obtained from the steady-state data. Condensation coefficients and their temperature dependence have been derived from the effusiion measurement. Condensation coefficients ranged from 0.159 to 0.048(475 to 500K), the activation enthalpy and entropy for condensation have been obtained as -93.38kTmol-1 and -212.70JK-1mol-1. The standard sublimation enthalpy changes derived by both second(modified sigma function) and third(average enthalpy method) law methods were 138.261$\pm$0.023, 138.74$\pm$0.002kJmol-1 respectively. The standard sublimation entropy change derived by modified sigma function was 191.98$\pm$0.047 JK-1mol-1. The reliable standard sublimation enthalpy change based on a correlation of ΔgcrHom(298.15K) and ΔgcrSom(298.15K), a recommended p(T) equation has been obtained for BiI3(cr) ; 1g(p/Pa)=-C/(T/K)＋5.0711g(T/K)-2.838$\times$10-3(T/K)-7.758$\times$103(K/T)2＋1.4519 where p is in Pa, T in Kelvin, ΔgcrHom(298.15K) in kJmol-1 and C=(ΔgcrHom(298.15K)-8.7358)/1.9146$\times$10-2.

• The Journal of Korean Medicine
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• v.29 no.3
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• pp.21-37
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• 2008

Objectives: The purpose of this study was to verify the effect of Palmiboshinwhan (PMBSW) in methotrexate (MTX)-induced immunosuppressed SD rats. Methods: The test articles were once a day dosed for 14 days by gastric gavage from 2 days after last MTX-dosing, and changes in body weight, spleen weight and total blood leukocyte numbers were observed with total lymphocyte numbers, B and T lymphocyte percentages, CD3+CD4+, CD3+/CD8+, CD4+/CD8+ T lymphocyte percentages in the blood and spleen, the serum interleukin (IL)-2 levels and the productivity of IL-2 of splenic cells. Result & Conclusion: It is concluded that PMBSW has relatively good immunostimulating effect in the MTX-induced immunosuppressed SD rats. Theefficient dosage was considered above 500mg/kg. In addition, it is considered that the immunostimulating effect of PMBSW was mediated to both the B and T lymphocytes. The more favorable effects were detected in T lymphocytes rather than B lymphocytes, and PMBSW showedrelatively good stimulating potential against CD4+ T lymphocytes but not any stimulating effect against CD8+ T lymphocytes in the present study.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.883-887
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• 2009

In this study, a new soil retaining system was proposed by soil cement mixing method. The new soil retaining system is based on deep cement mixing method by large diameter reinforcing blocks (piles). Large diameter reinforcing blocks (usually $\varnothing$300-500 mm) have the advantage to make reinforcements over a relatively short depth and thus reduce the amount of reinforcement necessary. A field case has been reviewed for actual application of the soil retaining system at a downtown site. Research was conducted to evaluate the behavior of the installed soil retaining wall, with reinforcing blocks (400 mm in diameter and 4 m in length) placed into a 10 m excavation wall at a $20^{\circ}$ angle. As a result, the potential for applying this method to the downtown excavation site was confirmed.

• Journal of Environmental Science International
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• v.21 no.10
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• pp.1203-1212
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• 2012

Yongsan ward is located at central place connecting south and north ecology axis of seoul. Various environment-friendly Yongsan development could pose positive effects on NPS(non pollutant source) pollutant reductions and water quality improvement at Han-rive because BOD, T-N, and T-P NPS discharges took 90% of total pollutant from this area. In this study, direct runoff and NPS pollutant loads were evaluated before and after development using spatio-tamporal change in CN(curve number) and EMC(event mean concentration) data. It was found that direct runoff value is $23,584,724m^3$, and BOD, T-N and T-P loads are 104,456 kg/year, 111,483 kg/year and 7,500 kg/year under pre-development condition, respectively. Annual runoff, BOD, T-N and T-P reducing rate were 12.9%, 33.3%, 35.6% and 40.7% under integrated post-development condition, respectively. Based on the results obtained in this study, environment-friendly urban development could be achieved at Yongsan area.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.09a
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• pp.1294-1300
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• 2009

Recently, excavations in highly congest urban area have been increased. For the excavations conducted in extremely narrow spaces, we have been developing a novel soil reinforcement system of temporary retaining walls by using deep cement mixing method. The developing method installs largerdiameter ($\Phi$=300~500mm) and shorter reinforcement blocks than previous reinforcement system for mobilizing friction with soils, therefore it has advantages of not only shortening the length of reinforcement system but also reducing the amount of reinforcement. In this study, we performed a numerical analysis of the new reinforcement system by using a commercial finite element program, and evaluated the behavior of the reinforced retaining wall system under various conditions of the length, the diameter, the spacing, and the angle of the reinforcement system.

• YAKHAK HOEJI
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• v.55 no.4
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• pp.309-313
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• 2011

Abnormal growth of adipocyte characterized by increased cell numbers and differentiation is considered as an major pathological characteristic feature in obesity. Thus, inhibition of mitogenesis of preadipocytes and their differentiation to adipocytes would be beneficial for the prevention and inhibition of obesity. In the present study, we attempted to evaluate anti-adipogenic activity of eggplants (the fruits of Solanum melongena L.) employing preadipocytes cell line, 3T3-L1 as an in vitro assay system. Water extract of eggplants significantly inhibited adipocyte differentiation when treated during adipocyte differentiation process, as assessed by measuring fat accumulation using Oil Red O staining. Eggplant extract, however, showed little effects on fully differentiated adipocytes. Eggplant didn't show significant toxicity up to 500 ${\mu}g$/ml to the 3T3-L1 cells. Further studies with interval treatment demonstrated that eggplant exerted inhibitory activity on adipocyte differentiation via acting on early stage of adipogenesis. Conclusively, eggplants are suggested to be beneficial for the prevention of obesity.

• Journal of Ocean Engineering and Technology
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• v.33 no.2
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• pp.178-188
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• 2019

When burying underwater cables using robots, heading control is one of the key functions for the robots to improve task efficiency. This paper addresses the heading control issue for URI-T, an ROV for underwater construction tasks, including the burial and maintenance of cables or small diameter pipelines. Through modeling and identifying the heading motion of URI-T, the dynamic characteristics and input limitation are analyzed. Based on the identification results, a PD type controller with appropriate input treatment is designed for the heading control of URI-T. The performance of the heading controller was verified in water tank experiments. The field applicability of the proposed controller was also evaluated through the sea trial of URI-T at the East Sea, with a water depth of 500 m.