• Journal of the Korean Society of Safety
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• v.23 no.4
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• pp.79-84
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• 2008

Auto injector grouting method as low pressure injected by using epoxy and Boyle's law is very excellent method in economical efficiency and construction work because injected process can be dealt with collectively. For estimation of filling capacity purpose of this study compared the Auto injector method with the piston injector method. In this study, the tests allow for width of crack, injected angle of epoxy resin and injected method were performed using concrete block specimen making artificial crack. The results of test, tilling et1iciency of epoxy by Auto Injector grouting method verify to better than the piston injector method and uniaxial strength increased about 11% than standard specimen.

• Korean Journal of Clinical Laboratory Science
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• v.51 no.4
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• pp.504-513
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• 2019

The purpose of this study was to determine the antidiabetic and antioxidative effects of Bitter melon on streptozotocin-induced diabetic rats. The normal and the control groups were fed an AIG -93M diet, and the Bitter melon groups were fed 1%, 2% and 3% Bitter melon powder. After two weeks, the control and the experimental group were induced to a diabetic state with the administration of streptozotocin. The blood glucose control and antioxidant activity were analyzed after the animals were sacrificed. The blood glucose levels of all the Bitter melon groups were lower than those of the control group, and the 2% Bitter melon group showed significantly lower blood glucose levels than those of the control group. Serum Triglyceride and HDL-cholesterol of the 2%, and 3% Bitter melon groups were significantly lower than those of the control group. The total cholesterol levels of the bitter melon groups were significantly lower than those of the control group. The serum insulin levels of the induced groups were significantly lower than those of the normal group. The HbA1c levels of the 2% and 3% Bitter melon groups were significantly lower than those of the control group. For the level of antioxidant enzymes in the liver tissues, the 2% Bitter melon group was significantly higher than that of the control group. These results show the antidiabetic and antioxidative effects of Bitter melon for the prevention and treatment of diabetes.

• International Area Studies Review
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• v.13 no.3
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• pp.613-636
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• 2009

This paper examines the performance of assessing sponsors and non-sponsors recall and recognition at the 2008 Beijing Olympic Games perceived by Korean and Chinese university students. Using a sample of 1,573 respondents, a survey was administered in Seoul and Beijing before and after Games to compare the recall and recognition that changed between two periods. The findings reveal that the effectiveness of the 2008 Beijing Olympic sponsorship has was lower than we expected. Results were founded that while Samsung(mobile), Coca-cola, McDonald's, and Visa achieved the desired sponsorship marketing effectiveness in Korea. On the other hand, non-sponsors of Nike, Dell, AIG, Samsung(computer) and Hyundai led to obtain the benefit and resulted in increasing consumer confusion as to who is a sponsor. In China, Samsung, Coca-cola, Lenovo, Volkswagen, Visa, and PICC achieved the desired sponsorship marketing effectiveness. On the other hand, Lining, Nokia, KFC, China Merchants Bank had some impact on the effectiveness of a rival brand from an official sponsor's product category. The paper concludes by considering some issues for sponsorship marketers.

• Journal of Environmental Science International
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• v.22 no.11
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• pp.1481-1498
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• 2013

The SCR (selective catalytic reduction) system is highly-effective technique for NOx reduction from exhaust gases. In this study, the effects of the direction and size of nozzle and the ammonia injection concentration on the performance of SCR system are analyzed by using the computational fluid dynamics method. When the nozzle is arranged in zigzaged direction which is normal to exhausted gas flow, it is shown that the uniformity of gas flow and the NH3/NO molar ratio is improved remarkably. With the change of the ammonia injection concentration from 0.2 vol%(wet) to 1.0 vol%(wet), the uniformity of gas flow shows a good results. As the size of nozzle diameter changes from 6 mm to 12 mm, the uniformity of gas flow is maintained well. It is shown that the uniformity of the $NH_3/NO$ molar ratio becomes better with decreasing the ammonia injection concentration and the size of nozzle diameter.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.2
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• pp.137-142
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• 2011

In this paper, the fault current limiting and the hysteresys characteristics of a superconducting fault current limiter (SFCL) using magnetic coupling of two coils on the iron core with an air-gap were analyzed. The introduction of the air-gap in the SFCL with magnetically coupled two coils can suppress the saturation of the iron-core and, on the other hand, make the limiting impedance of the SFCL decreased, which results from the increase of the exciting current. To analyze the effect of the aig-gap on the fault current limiting characteristics of the SFCL, the hysteresys curves of the iron core comprising the SFCL were derived from the short-circuit experiment and the variation in the voltage-current trace of the SFCL during the fault period was analyzed. Through the comparison with the current limiting characteristics of the SFCL without air-gap, the air-gap could be confirmed to contribute to the suppression of the iron core's saturation through the increase of the SFCL's burden from the short-circuit current.

• Environmental Engineering Research
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• v.22 no.4
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• pp.339-346
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• 2017

The objective of this study is the evaluation of the performance of a large-scale respirometer (LSR) of 17.7 L in the determination of the methane generation rate constant (k) values. To achieve this objective, a comparison between anaerobic (GB21) and LSR tests was conducted. The data were modeled using a linear function, and the resulting correlation coefficient ($R^2$) of the linear regression is 0.91. This result shows that despite the aerobic conditions, the biodegradability values that were obtained from the LSR test produced results that are similar to those from the GB21 test. In this respect, the LSR test can be an indicator of the anaerobic biodegradability for landfill waste. In addition, the results show the high repeatability of the tests with an average coefficient of variance (CV) that is lower than 10%; furthermore, the CV for the LSR is lower than that of the GB21, which indicates that the LSR-test method could provide a better representation of waste samples. Therefore, the LSR method allows for both the prediction of the long-term biodegradation potential in a shorter length of time and the reduction of the sampling errors that are caused by the heterogeneity of waste samples. The k values are $0.156y^{-1}$ and $0.127y^{-1}$ for the cumulative biogas production (GB21) and the cumulative oxygen uptake for the LSR, respectively.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.12
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• pp.4989-4994
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• 2014

Background: It has been reported that COX-2 expression is associated with MMP-2 expression in thyroid and breast cancers, suggesting that MMPs are linked to COX-2-mediated carcinogenesis. Several polymorphisms within the MMP2 promoter region have been reported in cases with oncogenesis and tumor progression, especially in colorectal carcinogenesis. Materials and Methods: This research evaluated risk of association of the SNPs, including genes for COX-2 (AIG transition at +202) and MMP-2 (Crr transition at-1306), with colorectal cancer in 125 patients and 125 healthy controls. Results and Conclusions: Our data confirmed that MMP2 C-1306 T mutations were significantly more common in colon cancer patients than in our control Saudi population; p=O.0121. On the other hand in our study, there was no significant association between genotype distribution ofthe COX2 polymorphism and colorectal cancer; p=0.847. An elevated frequency ofthe mutated genotype in the control group as compared to the patients subjects indeed suggested that this polymorphism could decrease risk in the Saudi population. Our study confirmed that the polymorphisms that could affect the expressions of MMP-2 and COX-2 the colon cancer patients were significantly higher than that in the COX-2 negative group. The frequency of individuals with MMP2 polymorphisms in colon cancer patients was higher than individuals with combination of COX2 and MMP2 polymorphisms. Our study confirmed that individuals who carried the polymorphisms that could affect the expressions ofCOX2 are more susceptible to colon cancer. MMP2 regulatory polymorphisms could be considered as protective; further studies need to confirm the results with more samples and healthy subjects.

• Bulletin of the Korean Chemical Society
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• v.35 no.8
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• pp.2311-2316
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• 2014

Conformations and vibrational frequencies of the racemic (2RS,3RS)-5-amino-3-(4-phenylpiperazin-1-yl)-1,2,3,4-tetrahydronaphthalen-2-ol-(I) [(2RS,3RS)-(I)], a precursor of benzovesamicol analogues, have been carried out using various DFT methods (M06-2X, B3LYP, B3PW91, PBEPBE, LSDA, and B3P86) with basis sets of 6-31G(d), 6-31+G(d,p), 6-311+G(d,p), 6-311++G(d,p), cc-pVTZ, and TZVP. The LSDA/6-31G(d) level of theory shows the best performance in reproducing the X-ray powder structure. However, the PBEPBE/cc-pVTZ level of theory is the best method to predict the vibrational frequencies of (2RS,3RS)-(I). The potential energy surfaces of racemic pairs (2RS,3RS)-(I) and -(II) are obtained at the LSDA/6-31G(d) level of theory in the gas phase and in water. The results indicate that (2RS,3RS)-(I) are more stable by ~0.75 kcal/mol in energy than (2RS,3RS)-(II) in water, whereas conformer AIIg and BIIg are more stable by ~0.04 kcal/mol than AIg in gas phase. In particular, the hydrogen bond distances between the N of piperazine and the OH of tetrahydronaphthalen become longer in gas, compared with those in the water phase. Vibrational frequencies calculated at the PBEPBE/cc-pVTZ level of theory in the gas phase are larger than those in water, whereas their intensities in the gas phase are weaker than those in water.

• Journal of the Korea Society of Computer and Information
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• v.28 no.1
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• pp.121-127
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• 2023

In this study, the design conditions and CFD analysis results are compared and reviewed in SCR that can optimally reduce nitrogen compounds. To this end, it was analyzed and compared using CFD to see if the design criteria were satisfied for the shell and tube areas of the boiler. In the SCR system, the analysis area is the gas/air heat exchanger on the shell side, and eight tubes of the gas/air heat exchanger on the tube side. Through CFD analysis, the gas velocity distribution on the primary catalyst side of the SCR system was designed to be 2.4%, and the NH3/NOx molar ratio distribution was 3.7%, which satisfied the design criteria. In addition, the uniformity of the temperature distribution was confirmed and the required condition of 260℃ or higher was satisfied. The angle of the gas entering the catalyst met the design conditions at 2.9 degrees, and the pressure loss that occurred also satisfied the design requirements. Through this CFD analysis, it was confirmed that it was designed and operated by satisfying the design conditions required for each area.

• Clean Technology
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• v.25 no.4
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• pp.324-330
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• 2019

The selective catalytic reduction system is a highly effective technique for the denitrification of the flue gases emitted from the industrial facilities. The distribution of mixing ratio between ammonia and nitrogen oxide at the inlet of the catalyst layers is important to the efficiency of the de-NOx process. In this study, computational analysis tools have been applied to improve the uniformity of NH₃/NO molar ratio by controlling the flow rate of the ammonia injection nozzles according to the distribution pattern of the nitrogen oxide in the inlet flue gas. The root mean square of NH₃/NO molar ratio was chosen as the optimization parameter while the design of experiment was used as the base of the optimization algorithm. As the inlet conditions, four (4) types of flow pattern were simulated; i.e. uniform, parabolic, upper-skewed, and random. The flow rate of the eight nozzles installed in the ammonia injection grid was adjusted to the inlet conditions. In order to solve the two-dimensional, steady, incompressible, and viscous flow fields, the commercial software ANSYS-FLUENT was used with the k-𝜖 turbulence model. The results showed that the improvement of the uniformity ranged between 9.58% and 80.0% according to the inlet flow pattern of the flue gas.