• Proceedings of the SAREK Conference
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• 2004.11a
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• pp.136-136
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• 2004

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2016.10a
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• pp.421-422
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• 2016

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2016.10a
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• pp.357-358
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• 2016

• Journal of Radiation Protection and Research
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• v.37 no.4
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• pp.202-207
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• 2012

The radioactivity inventory significantly affects all steps of decommissioning projects including planning, cost estimation, risk assessment, waste management and site remediation. The decommissioning project of the KRR-2 was completed in 2009 and a large amount of activated concrete waste was generated. The bioshield concrete, containing minute amount of impurity elements, was activated by neutron reaction during the operation of the reactor. A variety radionuclides was generated in the concrete, including $^3H$, $^{14}C$, $^{55}Fe$, $^{60}Co$ $^{63}Ni$, $^{134}Cs$, $^{152}Eu$ and $^{154}Eu$. In this paper, the comparison between the calculated results and previous measured results was carried out to estimate the inventory of the bioshield concrete of the KRR-2. The combined computer codes of MCNP5 and ORIGEN 2.1 for calculation of the distribution of neutron flux, cross-section and generation of radionuclides were used. The results were shown that 99.8% of the total radioactivity of $^3H$, $^{55}Fe$, $^{60}Co$ and $^{152}Eu$ in the bioshield concrete 12 years after shutdown. The effects on the variation of inventory were analysed depending on the operation periods and the cooling times in the bioshield concrete.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.105-105
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• 2015

포항가속기연구소 PLS-II 저장링에 설치 운용중인 In-vacuum undulator (이하, IVU) 내부 Cu/Ni foil에 발생한 국부적 손상에 대하여, 원인을 분석하고 수리 및 정상 운용을 위한 절차들이 진행 되었다. 해체된 IVU의 손상부위를 세밀하게 조사하고 손상 원인에 대하여 다각도로 분석하였다. 손상된 Cu/Ni foil은 개선된 신규 제품으로 교체하고, 손상 원인이 될 수 있는 부품들을 제거토록 하였다. IVU 내부 관측을 위한 장치를 추가 설치하고 안정적인 온도 데이터 획득을 위한 노력도 함께 검토 되었다. 본 발표는 IVU 손상에 대한 원인분석 내용과 함께 해체, 수리, 재설치 과정 등에 대한 종합적인 내용으로 한다.

• 월간 기계설비
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• s.226
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• pp.53-57
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• 2009

그동안 많은 논란이 있었던 석면문제가 또다시 도마 위에 올랐다. 최근 아기에게 바르는 파우더를 비롯하여 화장품 등에까지 석면공포가 확산됨에 따라 환경부는 석면이 주로 건축자재(80% 이상)에 사용된 만큼 국민건강 보호를 위해 건축물에 사용된 석면의 안전한 관리가 무엇보다 중요하다고 판단, 가이드라인을 제정, 시행에 들어갔다. 가이드라인의 주요 내용은 $\Delta$건축물에 사용된 석면함유 설비 또는 자재를 조사하여 석면지도 작성 및 6개월마다 훼손 여부 평가 관리 $\Delta$석면 해체 제거작업 과정에서 석면이 비산되지 않도록 주변 대기 중 석면농도 0.01개/cc(실내공기질 권고기준) 기준 설정 $\Delta$석면 해체 제거 작업 및 폐석면 처리 시 안전한 석면관리를 위한 준수사항 등이다. 이번 가이드라인은 건축물 사용단계부터 철거 폐기까지 전 생에에 걸친 석면 관리 방법 및 기준 등을 포함하고 있어 건축물 이용자, 철거지역 인근 주민의 석면 노출 차단에 기여할 것으로 기대된다. 환경부는 가이드라인을 자치단체, 다중이용시설 관리자, 건축물 철거업체 등을 통해 널리 알리는 한편, 노동부 등 관계부처와 함께 관련제도 보완 등 건축물 석면관리 개선방안을 오는 6월까지 마련할 계획이다.

• Korean Journal of Heritage: History & Science
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• v.44 no.2
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• pp.76-95
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• 2011

After dismantled, Mireuksajiseoktap(Stone pagoda of Mireuksa Templesite) is being in the stage of restoration design. Now, different ways - producing restoration model, a 3 dimension simulation - have been requested to make more detailed and clearer restoration design prior to confirmation of its restoration design and actual restoration carry-out. This thesis proposes the way to build the detailed model for better restoration plan using extensively-used Reverse Engineering technique and Rapid Prototyping. It also introduces each stage such as a 3-dimension actual measurement, building database, a 3-dimension simulation etc., to build a desirable model. On the top of that, this thesis reveals that after dismantled, MIruksaji stone pagoda's interior and exterior were not constructed into pieces but wholeness, so that its looks can be grasped in more virtually and clearly. Secondly, this thesis makes a 3-dimension study on the 2-dimension design possible by acquiring basic materials about a 3-dimension design. Thirdly, the individual feature of each member like the change of member location can be comprehended, considering comparing analysis and joint condition of member. Lastly, in the structural perspective this thesis can be used as reference materials for structure reinforcement design by grasping destructed aspects of stone pagoda and weak points of the structure. In dismantlement-repair and restoration work of cultural properties that require delicate attention and exactness, there may be evitable errors on time and space in building reinforcement and restoration design based on a 2-dimension plan. Especially, the more complicate and bigger the subject is, the more difficult an analysis about the status quo and its delicate design are. A series of pre-review, based on the 3-dimension data according to actual measurement, can be one of the effective way to minimize the possibility that errors about time - space happen by building more delicate plan and resolving difficulties.

• Resources Recycling
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• v.22 no.2
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• pp.29-36
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• 2013

Although Korean domestic production of flat panel displays totalled more than 48 trillion KRW in 2007, most of the flat panel display wastes have been land-filled or incinerated, which greatly overshadows Korean national prestige as a world leading producer and developer of flat panel display devices. Countries such as Japan or EU possess quite limited land-fill capability and have sought ways to dispose of WEEEs from environment-friendly perspective rather than recovery of valuable materials from the wastes. Considering relatively short cycle of about 5 years for flat panel display devices, it is estimated that more than 5 million units will be accumulated as wastes by 2015. Urban mining is a most suitable countermeasures against China's monopoly of rare and rare earth metals, which are contained in flat panel display wastes. Therefore, materials recycling of waste LCD units has to be developed and commercialized soon enough for economic and environment-friendly recovery of valuable resources hidden in LCD wastes.

• Explosives and Blasting
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• v.29 no.1
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• pp.17-26
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• 2011

In this study, the pollutants contained in water and soil samples taken from the explosive demolition site were examined to investigate the effects on environment, and management plan of non-point source pollution in the demolition site was suggested through characterizing the movement of the pollutant with time. As results, pH value of the water and soil samples after the demolition work was 8.5~9.3 which exceeds the Korean environmental criterion of water and soil range due to calcium hydroxide compounds in the concrete. The concentration level of heavy metals caused by the explosive demolition doesn't exceed the environmental criterion of water and soil doesn't exceed the environmental criterion of water and soil quality, and the influence of water and soil pollution on the environment was not considered. The concentration of the heavy metals was analyzed and that of Cr, Cu, Zn and Hg among the heavy metals increased after the drilling and explosive demolition. This says that concentration of the heavy metals during explosive demolition works needs to be monitored. The most pollutants with time or rain dilution into the demolition site decreased and this means that the pollutants caused by the explosive demolition might have influenced to vicinity of the demolition sites as non-point pollution.

• Journal of the Korea Institute of Building Construction
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• v.23 no.4
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• pp.417-428
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• 2023

The demolition of domestic infrastructures mirrors other significant construction initiatives in presenting a markedly high accident rate. A comprehensive investigation into the origins of such accidents is crucial for the prevention of future incidents. Upon detailed inspection, the causes of demolition construction accidents are multifarious, encompassing unsafe worker behavior, hazardous conditions, psychological and physical states, and site management deficiencies. While statistics relating to demolition construction accidents are consistently collated and reported, there exists an exigent need for a more foundational cause categorization system based on accident type. Drawing from Heinrich's Domino Theory, this study classifies the origins of accidents(unsafe behavior, unsafe conditions) and human errors(human factors) as per the type of accidents experienced during demolition construction. In this study, a three-step model of QFD-FMEA(Quality Function Deployment - Failure Mode Effect Analysis) is employed to systematically categorize accident causes according to the types of accidents that occur during demolition construction. The QFD-FMEA method offers a technique for cause classification at each stage of the demolition process, including direct causes(unsafe behavior, unsafe environment), and human errors(human factors) through a tri-stage process. The results of this accident cause classification can serve as safety knowledge and reference checklists for accident prevention efforts.