• Journal of the Society of Naval Architects of Korea
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• v.48 no.4
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• pp.325-329
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• 2011

Floating, production, storage and offloading (FPSO) is a production facility that refines and saves the drilled crude oil from a drilling facility in the ocean. The flare system in the FPSO is a major part of the pressure relieving system for hydrocarbon processing plants. The flare system consists of a number of pipes and complicated connection systems. Decision of pipe support types is important since the load on the support and the stress in the pipe are influenced by the pipe support type. In this study, we optimally determined the pipe support types that minimized the support cost while satisfying the design constraints on maximum support load, maximum nozzle load and maximum pipe stress ratio. Performance indices included in the design constraints for a specified design were evaluated by pipe structural analysis using CAESAR II. Since pipe support types were all discrete design variables, an evolutionary algorithm (EA) was used as an optimizer. We successfully obtained the optimal solution that reduced the support cost by 27.2% compared to the initial support cost while all the design requirements were satisfied.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.656-657
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• 2010

The ground oxidizer supply system in the launch site of NARO space center had operated 9 times from the start of tests with ILV on May, 2009 to the 2nd flight test of the NARO vehicle. This system operated successfully for twice launches of the NARO vehicle. To judge the successful operation of the ground facility, it should have reproducibility and reliability. In this report, we have analyzed the liquid oxygen consumption of the system to judge of its reproducibility and it can be a reference for using this system for the next generation of KSLV system.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.2053-2058
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• 2004

The pressurized light water cooled, medium power (330 MWt) SMART (System-integrated Modular Advanced ReacTor) has been under development at KAERI for a dual purpose : seawater desalination and electricity generation. The SMART design verification phase was followed to conduct various separate effects tests and comprehensive integral effect tests. The high temperature / high pressure thermal-hydraulic test facility, VISTA(Experimental Verification by Integral Simulation of Transient and Accidents) has been constructed to simulate the SMART-P (the one fifth scaled pilot plant) by KAERI. Experimental tests have been performed to investigate the thermal-hydraulic dynamic characteristics of the primary and the secondary systems. Heat transfer characteristics and natural circulation performance of the PRHRS (Passive Residual Heat Removal System) of SMART-P were also investigated using the VISTA facility. The coolant flows steadily in the natural circulation loop which is composed of the steam generator (SG) primary side, the secondary system, and the PRHRS. The heat transfers through the PRHRS heat exchanger and ECT are sufficient enough to enable the natural circulation of the coolant.

• Journal of the Korean Institute of Landscape Architecture
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• v.13 no.1
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• pp.67-77
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• 1985

The purpose of this study is to establish the principles of an arrangement planning for children's playgrounds which can be contributed to offer the recreation opportuqities to all urban children equally. The study is specially focused on the service radius and the inducement rate in children's playground. The data in this study were made into field survey, dividing the park users into preschool children (below 6- year-old)and school children (7 to 12-year - old), through six sampling places in Taegu City. The results are summarized as follows : The using distance was becoming shorter according as the dencity of population was becoming high. There wart 75% of the users to service radius 250m prescribing in the present City Park Law. The service radius of preschool children was 260m and that of school children was 300m in average. To investigate the effects of several attributes on the inducement of children's playground, three of six children's playgrounds were selected based on three attributes of those which were width of area, percentage of green coverage and the pattern of facility arrangment. Of three children's playgrounds, Sankyok 3- dong which had the highest percentage of green coverage, the greatest width of area and the corner type in the arrangement was a slight tendency to become the same in the inducement rate of the two age group. In the using pattern of this Sankyok 3-dong. preschool children usually used a play facility, on the contrary, school children showed the active play pattern by using space.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2012.05a
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• pp.96-99
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• 2012

The test facility for confirming performance of a propulsion system is essential infra-structure to develop launch vehicle system. Using the PSTC, cold flow and combustion tests are performed to the propulsion system of individual stage in launcher. Moreover the ground test for the total launching process is conducted. In order to construct the PSTC, we not only have surveyed technology of internal and external countries, but also actively use the case in terms of the system. The test facility consists of feeding system, test stand, control and measurement, and flame deflector.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.364-364
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• 2010

In the electricity control field, a relay is the most widely used electrical switch. But it has problems about a material transfer phenomenon, contact bounce, and the mechanical life. These Problems cause the serious problem in a facility. So, we tried to solve these problems by applying MOSFET electronic switch and could find good improvement compared to conventional electrical switch.

• Proceedings of the Korean Nuclear Society Conference
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• 2003.05a
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• pp.148-148
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• 2003

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2007.11a
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• pp.120-125
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• 2007

• Journal of Environmental Policy
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• v.5 no.2
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• pp.27-47
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• 2006

Attempts were made to increase an efficiency of soil contamination investigation systems(SCISs) including Soil Contamination Fact-Finding Investigation Sites and Special Soil Contamination Management Facility Sites in Korea. In order to increase low efficiencies resulting from inappropriate SCISs, possible policy suggestions are driven based on the results from problem findings of Korean policy and comparisons of policies in industrialized countries including United States, United Kingdom, Germany, the Netherlands and Japan. First, functions of Soil Environment Conservation Act(SECA) on liability should be updated and reinforced to initiate a soil contamination investigation process for stakeholders including an owner(s) or a responsible party(ies) of the potentially soil contamination sites positively. Second, appropriate SCISs should be emerged for implementing the Soil Contamination Fact-Finding Investigation Sites and Special Soil Contamination Management Facility Sites properly. Stakeholders for the potentially contaminated sites should easily access and raise the soil contamination issues, and soil contamination investigation implemented by liable and profit environment (consulting) companies should be encouraged. Third, the soil contamination reporting system of SECA needs to change legally responsible. Further more, public announcement system showing soil quality of a site which exceeds a certain scale would be considerable. Fourth, liable environment (consulting) companies should legally execute Soil Environment Assessment of SECA.

• Journal of Microbiology and Biotechnology
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• v.33 no.5
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• pp.591-599
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• 2023

Fisetin is a bioactive flavonol molecule and has been shown to have antioxidant potential, but its efficacy has not been fully validated. The aim of the present study was to investigate the protective efficacy of fisetin on C2C12 murine myoblastjdusts under hydrogen peroxide (H₂O₂)-induced oxidative damage. The results revealed that fisetin significantly weakened H₂O₂-induced cell viability inhibition and DNA damage while blocking reactive oxygen species (ROS) generation. Fisetin also significantly alleviated cell cycle arrest by H₂O₂ treatment through by reversing the upregulation of p21WAF1/CIP1 expression and the downregulation of cyclin A and B levels. In addition, fisetin significantly blocked apoptosis induced by H₂O₂ through increasing the Bcl-2/Bax ratio and attenuating mitochondrial damage, which was accompanied by inactivation of caspase-3 and suppression of poly(ADP-ribose) polymerase cleavage. Furthermore, fisetin-induced nuclear translocation and phosphorylation of Nrf2 were related to the increased expression and activation of heme oxygenase-1 (HO-1) in H₂O₂-stimulated C2C12 myoblasts. However, the protective efficacy of fisetin on H₂O₂-mediated cytotoxicity, including cell cycle arrest, apoptosis and mitochondrial dysfunction, were greatly offset when HO-1 activity was artificially inhibited. Therefore, our results indicate that fisetin as an Nrf2 activator effectively abrogated oxidative stress-mediated damage in C2C12 myoblasts.