• Journal of the Korean Recycled Construction Resources Institute
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• v.6 no.1
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• pp.111-119
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• 2011

Recently, urban redevelopment programs and expansion of social infrastructure have caused massive amounts of construction waste in construction fields, and the mounds of it keep increasing every year. The disposal of construction waste is emerging as a national and social issue and the recycled powder generated by the treatment process of waste concrete is all being abolished or buried. Therefore, the purpose of this study is to utilize waste sludge generated by the wet-type treatment process of waste concrete as materials(binder, filler) for cement composite. This study evaluates physical and mechanical properties of mortar using recycled powder according to heating temperature, contents and applications. As a result of the chemical analysis, recycled powder is composed mainly of CaO and $SiO_2$, and that it is even lower in the content of CaO than OPC. The charateristics of mortar using recycled powder, according to drying and heating temperature, shows that as the heating temperature increases, flow decreases. Also, compressive strength and porosity of mortar using recycled powder was superior when heating temperature was $600^{\circ}C$. Thus, it is revealed that an effective development of recycled powder is possible since the binder by cement composite recovers a hydraulic property during heating at $600^{\circ}C$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.9
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• pp.1194-1199
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• 2006

Effects of Korean traditional soybean fermented foods on weight reduction and lipid lowering activities were studied using Spraque-Dawley (SD) rats fed a high fat diet. The rats were raised for four weeks after adaptation period on either a normal diet (ND, based on the AIN-93 diet), high fat diet (HFD, supplemented with 12% lard oil in the ND), or diets containing 10% of freeze dried Doenjang, Chungkukjang, Kochujang, or Samjang to HFD. The final weight, food efficiency ratio (FER) and the weight of adipose tissue were decreased significantly by the consumption of Doenjang and Samjang, compared to HFD (p<0.05). The contents of cholesterol and triglyceride increased by HFD were reduced by the fermented foods in liver and perirenal fat tissues of the rats, especially Doenjang and Samjang diets showed high lipid lowering activity. And TG and cholesterol contents in the plasma serum were simillar trend to liver and perirenal fat tissue. These results suggested that Korean traditional soybean fermented foods, especially Doenjang showed the highest weight reduction and lipid lowering activities of the rats fed high fat diet.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.12
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• pp.1497-1502
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• 2007

The antioxidant effect of Korean cabbage kimchi containing 20% of sea tangle (SK) was studied in the rats fed with high fat diet (HFD) for 8 weeks. The rats (n=40) were divided into four experimental groups as a high fat diet group (HFD), HFD supplemented either with Korean cabbage kimchi used as experimental control (HCK), with SK (HSK), or with J-kimchi (HJK) that was purchased at the local market. The amount of kimchi supplemented was 10%. DPPH radical scavenging activities of SK were significantly higher than those of CK. Kimchi suppressed the hepatic lipid peroxidation significantly, especially by HSK (p<0.05). Inhibition of thiobarbituric acid reactive substances (TBARS) formation in HSK was the greatest among the kimchi groups (p<0.05). The activities of $Cu{\cdot}Zn$-superoxide dismutase (SOD), Mn-SOD and catalase decreased significantly (p<0.05) by kimchi supplementation. SOD and catalase activities of HSK were found to be the lowest among the kimchi groups. The decreased enzyme activity in kimchi group might be due to the less amount of lipid peroxides produced in the rats fed kimchi diet. The lowest antioxidative enzyme activities observed in HSK were in line with those of hepatic POV and TBARS of HSK. Our findings confirmed that kimchi acted as an antioxidant in the high fat fed rats and its antioxidant effect was significantly increased by the addition of sea tangle.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.12
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• pp.1529-1536
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• 2007

Anti-obesity effects of kimchi tablet composition (KTC) were investigated with male Sprague-Dawley rats fed high-fat diet for 8 weeks. Fifty rats were classified to 4 groups: normal diet (ND), high fat diet (HFD), HFD+KTC 5% and HFD+KTC 10% for feeding experiments. This research showed that the final weight, weight gain, food efficiency ratio and organ weight were decreased by the addition of KTC compared to those of HFD group. Amount of subcutaneous fat of KTC groups were 13.6% and 21.3%, respectively. The plasma triglyceride concentration of KTC groups was lower than that of high fat diet group. Plasma cholesterol concentration of all four groups were not significantly different. HDL-cholesterol concentration of KTC groups was higher than those of high fat diet group. In addition, triglyceride and cholesterol concentrations in the liver and heart were reduced by the addition of KTC. Moreover, triglyceride concentration of fecal and hepatic HMG-CoA reductase activity were increased in KTC group. These results suggested that KTC might be useful for obesity control and good source of functional kimchi tablet.

• Journal of Korea Port Economic Association
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• v.32 no.1
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• pp.123-133
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• 2016

LNG(Liquefied Natural Gas) bunkering has become an important issue with the enforcement of environment regulations in shipping industry required by the International Maritime Organization (IMO). With increased attention on LNG bunkering, many studies that focus on safety, regulation, demand forecasting, and the feasibility of LNG fueled ships have been carried out. However, most of the existing research has not included considerations of the price of LNG bunkering and its competitiveness. This paper, therefore, suggests ways to increase price competitiveness in the LNG bunkering market in the Busan Port. This paper analyzes the LNG bunkering supply mechanism by investigating various LNG bunkering terminal business in the LNG supply market. Factors that determine LNG bunkering price and its elasticity are also identified. Market players who want to operate LNG bunkering terminals in the Busan Port should introduce a merchandising trade method that is able to exclude the "Korea premium" in order to increase price competitiveness. This paper also suggests adoptable strategies such as the use of TPS (Terminal to Ship via Pipeline) type of bunkering service and the importance of location for minimizing initial investment cost.

• Journal of the Korean Society for Railway
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• v.20 no.3
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• pp.365-373
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• 2017

This study proposes a newly developed dry washing method for removing pollutants such as total petroleum hydrocarbon (TPH) and oxidized iron from the surface of ballast gravel. A batch-type dry washing method showed a good performance in a previous study. In this study, a continuous-type dry washing system, instead of a batch-type system, was prepared to improve the efficiency of the system. A drier and a separator were also applied to this system as pre-treatment process, and the performance of this system was evaluated. In this experiment, blasting media was blasted on the polluted gravels through 12 nozzles by a pressure of $5-6kg/cm^2$ for 20-30 mins to remove TPH and oxidized iron. It was found to be possible to remove 80-90% of TPH and oxidized iron by using this system. Several ways to improve the performance were suggested in this study.

• Journal of dental hygiene science
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• v.16 no.6
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• pp.424-431
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• 2016

This study compared the effects of programs according to management type by preparing a manual for oral muscle exercises that integrates oral movement and oral massage. The program was performed on 14 elderly patients in a seniors' college self-practice program group and 28 elderly patients in a social welfare center expert intervention group. In the self-practice group, an expert demonstrated oral muscle exercises and subsequently encouraged self-practice by selecting an oral muscle exercise leader. In the expert intervention group, an expert demonstrated oral exercises on a one-on-one basis and subsequently gave oral muscle massages. In the self-practice group, there was no difference in saliva secretion (p=0.213) or oral dryness (p=0.206), after the intervention, the expert intervention group showed improvements in saliva secretion (p=0.009) and oral dryness (p=0.007). There was no difference in program satisfaction between groups (p=0.143), and both groups reported high satisfaction. As seniors may have difficulty in maintaining oral health behaviors, a certain amount of expert intervention may be needed. The results suggest that both a self-practice oral exercise program and an expert intervention program can be effective elderly patients.

• Korean Journal of Environmental Biology
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• v.35 no.2
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• pp.207-214
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• 2017

There is little information about the seed longevity of wild plants, although seed bank storage is an important tool for biodiversity conservation. This study was conducted to predict the seed viability equation of Agastache rugosa. The A. rugosa seeds were stored at moisture contents ranging from 2.7 to 12.5%, and temperatures between 10 and $50^{\circ}C$. Viability data were fitted to the seed viability equation in a one step and two step approach. The A. rugosa seeds showed orthodox seed storage behaviour. The viability constants were $K_E=6.9297$, $C_W=4.2551$ $C_H=0.0329$, and $C_Q=0.00048$. The P85 of A. rugosa seeds was predicted to 152 years under standard seed bank conditions. The P85 predicted by seed viability equation can be used as basic information for optimization of seed storage processes.

• Journal of the Korea Organic Resources Recycling Association
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• v.24 no.2
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• pp.67-74
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• 2016

This study was purposed to evaluate the characteristic changes of the solidified livestock manure fuel(SLMF) through the application of compression treatment process. The compression process led to an increase of VS/TS ratio (Volatile solids/Total solids ratio) and moisture removal effect of SLMF. The amount of leachate withdrawn from dairy cattle manure and Hanwoo manure by compression were 21~26%(w/w) and 15~20%(w/w), respectively. The specific gravity of the leachate of dairy cattle manure and Hanwoo manure were 1.01 and 0.99, respectively. The dehydrated cow manure was easily processed into ball-shaped solidified fuel. The drying time of the SLMF was proportional to the diameter of the solidified fuel. The highest heating value was observed in diameter range of 10~15mm SLMF. It is concluded that the higher heating value of 10~15mm SLMF was related with the amount of fibrous matter contained in the SLMF.

• Journal of the Korean Geotechnical Society
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• v.32 no.4
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• pp.5-14
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• 2016

Numerical simulation of dynamic soil-pile-structure interaction embedded in a dry sand was carried out. 3D model of the dynamic centrifuge model tests was formulated in a time domain to consider nonlinear behavior of soil using the finite difference method program, FLAC3D. As a modeling methodology, Mohr-Coulomb criteria was adopted as soil constitutive model. Soil nonlinearity was considered by adopting the hysteretic damping model, and an interface model which can simulate separation and slip between soil and pile was adopted. Simplified continuum modeling (Kim et al., 2012) was used as boundary condition to reduce analysis time. Calibration process for numerical modeling results and test results was performed through the parametric study. Verification process was then performed by comparing numerical modeling results with another test results. Based on the calibration and validation procedure, it is identified that proposed modeling method can properly simulate dynamic behavior of soil-pile system in dry condition.