• Journal of the Korean Institute of Gas
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• v.16 no.6
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• pp.128-135
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• 2012

In this paper, we proposed a system and a scenario to raise efficiency of gas safety management by developing wireless ZigBee communication modules, smart-home gas safety appliances and the system suitable for gas safety. Our designed system consists of a micom gas meter, an automatic extinguisher, sensors, and a wall-pad. A micom-gas-meter monitors gas flow, gas pressure, and earthquake. An automatic fire extinguisher checks combustible gas leaks and temperature of $100^{\circ}C$(cut off) and $130^{\circ}C$(fire). Sensors measure smoke and CO gas. In our novel system, a micom-gas meter cut off inner valve with warnings, an automatic fire extinguisher cut off middle valve and spray extinguishing materials, and sensors generate signals when detecting smoke and CO and then take a next action. Gas safety appliances and sensors automatically takes measures, and transmit those information to a wall-pad. The wall-pad again transmits real time information to server. Users can check and manage gas safety situations by connecting BcN server through web or mobile application. We hereby devised scenarios for gas safety and risk management based on the smart, and demonstrated their efficiency through test applied to filed.

• Journal of the Korean Geosynthetics Society
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• v.20 no.4
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• pp.113-124
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• 2021

Underground environmental infrastructure and energy production facilities, which are recognized as avoidable facilities such as landfills, are emerging as an important social issue due to urbanization and economic growth. In order to safely construct a large-scale plant facility in the underground space, it is necessary to increase the utilization of the limited space layout and minimize unnecessary columns. In this study, the plant modularization method(Pipe Rack Module) was reviewed to solve the problems of work constraints, assembly and demolition, process system interconnection, and maintenance that occur when plant facilities are underground. In addition, plant module analysis was performed by applying various load conditions (earthquake load, device load, earth pressure load, etc.) to improve spatial layout usability and secure structure stability. Based on the analysis results under various boundary condition, the implications regarding the minimum installation interval and module arrangement (draft) of basic modules required for the construction of an underground combined plant were derived.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.11 no.4
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• pp.67-79
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• 1991

Geomrtric nonlinearity of axially and laterally loaded reinforced concrete slender columns has been generally considered by use of second order analysis such as $P-{\Delta}$ method. Complex procedure in second order analysis may not be a difficult problem with computer aid, however it has been seldom used in design offices because of the need of carefully decided input data. In lieu of second order analyses, the Korean and the American concrete codes have adopted the moment magnifier method. It is known, however, that this method results in too conservative design in some cases. Accuracy of the moment magnifier method to the experimentally obtained data has been reviewed and an improved method has been proposed for better result.

• Computational Structural Engineering
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• v.3 no.3
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• pp.141-146
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• 1990

This study is on a seismic analysis of absorber rod in KMRR Reactivity Control Mechanism. The model being studied is two coaxial tubes(control absorber rod and flow tube) immersed in the water and partially coupled(overlap) by water gap. The hydrodynamic mass effects by the water in each surrounding conditions are considered in the model. The natural frequencies, stresses and displacements of the system due to Safe Shutdown Earthquake are computed in the cases of in-phase modes and out-of-phase modes of two coaxial tubes. The results show that maximum stresses are well below the allowable limit but the maximum displacements at the ends of both tubes are so much that the absorber rod contacts with the flow tube(or surrounding wall).

• Journal of the Computational Structural Engineering Institute of Korea
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• v.26 no.3
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• pp.207-212
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• 2013

APR1000(Advanced Power Reactor 1000) was developed to export 1000MW nuclear power plants by adding ADFs(Advanced Design Features) including 60 years design life, local frequency control operation, 0.3g SSE, etc. to OPR1000(Optimized Power Reactor 1000). In this paper, environmental fatigue analyses for the reactor vessel in APR1000 have been performed as per Reg. Guide 1.207. Outlet nozzle, which has a relatively high cumulative usage factor in the reactor vessel was evaluated and a structural integrity is maintained under the reactor coolant environment.

• Fire Science and Engineering
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• v.23 no.6
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• pp.24-31
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• 2009

The Environment of disaster has more complicated, diversified and unpredicted sides, which causes extensive damage to humankind. Above all, presently the climatic change causes worldwide disaster of nature like cataclysm, intense heat, drought, earthquake and hard winter. After 9.11, most of countries continuously try to protect their own compatriots' life and property which forms the social safety net as well. This research investigates the current system used by the firerenation which is the national disaster response agency.ict also suggests the unation whiih is the nasystem unationdisaster mthe nasys accundihg to tionld el of disaster like the constructe naof DB, disaster cycld repunt, analysis of danger, facilities ih is ation system, disaster media system, location search system, disaster damage collection system.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.10 no.1
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• pp.63-75
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• 2012

This paper gives some basic requirements and preferences of various geological environmental conditions for the final deep geological repository of spent nuclear fuel (SNF). This study also indicates how the requirements and preferences are to be considered prior to the selection of sites for a site investigation as well as the final disposal in Korea. The results of the study are based on the knowledge and experience from the IAEA and NEA/OECD as well as the advanced countries in SNF disposal project. This study discusses and suggests preliminary guideline of the disposal requirements including geological, mechanical, thermal, hydrogeological, chemical and transport properties of host rock with long term geological stabilities which influence the functions of a multi-barrier disposal system. To apply and determine whether requirements and preferences for a given parameter are satisfied at different stages during a site selection and suitability assessment of a final disposal site, the quantitative criteria in each area should be formulated with credibility through relevant research and development efforts for the deep geological environment during the site screening and selection processes as well as specific studies such as productions of safety cases and validation studies using a generic underground research laboratory (URL) in Korea.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.262-262
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• 2015

풍수해보험은 국민안전처가 관장하고 민영보험사가 운영하는 정책보험으로 국민이 예기치 못한 풍수해 피해에 대처할 수 있도록 보험료의 일부를 국가 및 지방자치단체에서 보조해 주는 제도이다. 그러나 풍수해보험은 불합리한 보험요율체계 등의 문제점으로 인해 저조한 가입률을 보이고 있다. 현재 풍수해보험요율 산정시 과거의 피해이력만을 근거로 보험요율을 산정하고 있다. 또한 풍수해 보험은 태풍, 홍수, 호우, 강풍, 풍랑, 해일, 대설, 지진을 대상재해로 분류하고 있으나 동일 시군구 내에서는 재해요인별 원인별 가중치가 동일하게 적용되어 단일 보험요율을 적용하고 있다. 현재의 불합리한 보험요율체계의 문제점을 보완하고 향후 피해발생 위험을 고려하여 피해 특성에 따라 지역적으로 차등화된 보험요율을 적용하는 방안이 필요하다. 이에 따라 본 연구에서는 풍수해보험요율 산정을 위해 풍수해보험 대상재해 중 내수침수에 대한 분석 방안을 제시하고 적용성을 검토하고자 하였다. 우선 다양한 내수침수분석방법 중 전국단위의 내수침수분석을 위해 경제성, 간편성, 정확성을 고려하여 Level-Pool 방법을 선정하였다. 그리고 기존 Level-Pool 방법의 문제점을 보완하기 위해 내수침수분석 결과의 정확성을 향상시킬 수 있도록 도시계획 용도지역을 고려한 수정 Level-Pool 방법을 제시하고, 풍수해저감종합계획과 비교 검토를 실시하여 적용성을 검토하였다. 또한, 제시한 수정 Level-Pool 방법을 울산, 대구, 경북, 강원지역에 적용하여 내수침수위험지역을 도출하였다. 본 연구에서 제시한 수정 Level-Pool 방법을 통해 전국단위 내수침수 해석시 지역별로 차등화되고, 정확도가 높은 내수침수지역을 도출하여 풍수해보험요율 산정을 위한 기초자료로 활용할 수 있을 것으로 판단된다.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.198-198
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• 2019

2011년 동일본 지역에서 발생한 지진으로 인하여 후쿠시마 다이이치에 위치한 원자력 발전소에서 다양한 방사성 물질들이 바다, 하천 그리고 대기와 같은 자연환경 속으로 유출되었다. 방사성 세슘(Cesuim, $Cs^{137}$)은 다양한 방사성 물질들 가운데 반감기(Half-life)가 30.17년으로 가장 긴 물질이다. 방사성 세슘이 환경 생태계로 한번 유출될 경우 긴 반감기과 널리 퍼지는 성질로 인하여 오랜 시간동안 넓은 지역에 막심한 피해를 초래하므로 효과적인 처리방법을 통해 안전하게 처리하는 것이 아주 중요하다. 세슘을 제거하기 위하여 물리적, 화학적, 생물학적 등 다양한 방법들을 통해 연구를 진행하고 있으며, 특히 세슘을 제거하는 아주 효과적인 방법 중 하나인 프러시안 블루(Prussian Blue, PB) 흡착제를 적용하는 방법이 많이 주목받고 있다. 그러나 프러시안 블루는 미세한 분말입자로서 수처리에 사용하게 되면 처리 후 발생되는 슬러지들을 수중으로 부터 분리하기 어려운 한계점을 가지고 있다. 최근 연구에서는 프러시안 블루의 적용 한계점를 극복하기 위하여 자성체(Magnetic substance)를 물리적 지지체로 이용하여 외부 자기장을 통해 수중으로 분리하는 방법들이 연구되고 있다. 자성체란 외부 자기장이 주어지게 되면 입자들 표면에 자성력을 띄는 물질들을 말한다. 본 연구에서는 자성체 종류들 가운데 가장 높은 자성력을 지닌 강자성체(Ferromagnetic Substance)를 물리적 지지체로 하여 산화과정, 실란과정, 합성과정을 거쳐 강자성체 입자의 표면에 프러시안 블루를 합성한 새로운 형태에 합성체를 제조하고, 제조된 합성체를 이용하여 수중에 존재하는 세슘 제거 능력을 평가하였다. 제조된 합성체의 물리적 특성을 분석하기 위하여 SEM, XRD를 이용하여 합성체 입자의 표면 분석을 진행하였다. 합성체의 세슘 제거 능력을 평가하기 위하여 임의 제조된 0.5mg/L의 세슘 농도를 가진 원수 100ml에 제조된 새로운 형태의 합성체 1g을 투입한 뒤 1분간의 반응시간 동안 반응한 이후 잔류 세슘을 측정한 결과 수중의 존재하는 세슘에 대해 99.9%의 세슘 제거율을 기록하였다. 자가분리(Magnetic Seperate)의 원리를 이용하여 수중으로부터 회수율을 측정한 결과, 99%의 합성체 회수율을 얻었다. 실험결과를 통해 외부자기장이 주어지게 되면 수중으로부터 합성체를 대부분 분리하여 회수할 수 있다고 판단된다. 본 연구를 통해 개발된 새로운 형태의 합성체는 수중의 세슘 처리 공정에서 사용자가 직접 접촉하지 않고 세슘제거 및 외부자기장을 통해 수중으로부터 분리가 가능한 합성체라고 판단된다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.7
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• pp.1269-1276
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• 2016

Recently, natural disasters including earthquakes, tsunamis, floods, and snowstorms, in addition to disasters of human origin such as arson, and acts of terror, have caused numerous injuries and fatalities around the world. During such disasters, victims need to obtain information such as the exact location of the disaster and appropriate evacuation routes in order to relocate to safe areas. In this study, We propose the algorithm for Emergency Rescue Evacuation Support System(ERESS). In case a emergency disaster occurs, ERESS is possible to detect it quickly using through the movement of people. The mobile terminal analyzes behavior and location of indoor pedestrian. And it sends the result to the server. The server determines whether an emergency situation occurred or not based on the received transmission information. When an emergency situation occurs, the server will notify it to the mobile terminal. Then, indoor pedestrian conduct emergency evacuation using mobile terminal.