• Safety and Health at Work
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• 제12권2호
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• pp.174-183
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• 2021

Background: Toluene diisocyanate (TDI) is a highly reactive chemical that causes sensitization and has also been associated with increased lung cancer. A risk assessment was conducted based on occupational epidemiologic estimates for several health outcomes. Methods: Exposure and outcome details were extracted from published studies and a NIOSH Health Hazard Evaluation for new onset asthma, pulmonary function measurements, symptom prevalence, and mortality from lung cancer and respiratory disease. Summary exposure-response estimates were calculated taking into account relative precision and possible survivor selection effects. Attributable incidence of sensitization was estimated as were annual proportional losses of pulmonary function. Excess lifetime risks and benchmark doses were calculated. Results: Respiratory outcomes exhibited strong survivor bias. Asthma/sensitization exposure response decreased with increasing facility-average TDI air concentration as did TDI-associated pulmonary impairment. In a mortality cohort where mean employment duration was less than 1 year, survivor bias pre-empted estimation of lung cancer and respiratory disease exposure response. Conclusion: Controlling for survivor bias and assuming a linear dose-response with facility-average TDI concentrations, excess lifetime risks exceeding one per thousand occurred at about 2 ppt TDI for sensitization and respiratory impairment. Under alternate assumptions regarding stationary and cumulative effects, one per thousand excess risks were estimated at TDI concentrations of 10 - 30 ppt. The unexplained reported excess mortality from lung cancer and other lung diseases, if attributable to TDI or associated emissions, could represent a lifetime risk comparable to that of sensitization.

• Nuclear Engineering and Technology
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• 제49권2호
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• pp.411-425
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• 2017

Using a probabilistic safety assessment, a risk evaluation framework for an aircraft crash into an interim spent fuel storage facility is presented. Damage evaluation of a detailed generic cask model in a simplified building structure under an aircraft impact is discussed through a numerical structural analysis and an analytical fragility assessment. Sequences of the impact scenario are shown in a developed event tree, with uncertainties considered in the impact analysis and failure probabilities calculated. To evaluate the influence of parameters relevant to design safety, risks are estimated for three specification levels of cask and storage facility structures. The proposed assessment procedure includes the determination of the loading parameters, reference impact scenario, structural response analyses of facility walls, cask containment, and fuel assemblies, and a radiological consequence analysis with dose-risk estimation. The risk results for the proposed scenario in this study are expected to be small relative to those of design basis accidents for best-estimated conservative values. The importance of this framework is seen in its flexibility to evaluate the capability of the facility to withstand an aircraft impact and in its ability to anticipate potential realistic risks; the framework also provides insight into epistemic uncertainty in the available data and into the sensitivity of the design parameters for future research.

• Nuclear Engineering and Technology
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• 제39권4호
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• pp.287-298
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• 2007

As part of the $AP1000^{TM}$ pressurized water reactor design certification program, a series of integral systems tests of the nuclear steam supply system was performed at the APEX-1000 test facility at Oregon State University. These tests provided data necessary to validate Westinghouse safety analysis computer codes for AP1000 applications. In addition, the tests provided the opportunity to investigate the thermal-hydraulic phenomena expected to be important in AP1000 small-break loss of coolant accidents (SBLOCAs). The APEX-1000 facility is a 1/4-scale pressure and 1/4-scale height simulation of the AP1000 nuclear steam supply system and passive safety features. A series of eleven tests was performed in the APEX-1000 facility as part of a U.S. Department of Energy contract. In all, four SBLOCA tests representing a spectrum of break sizes and locations were simulated along with tests to study specific phenomena of interest. The focus of this paper is the SBLOCA tests. The key thermal-hydraulic phenomena simulated in the APEX-1000 tests, and the performance and interactions of the passive safety-related systems that can be investigated through the APEX-1000 facility, are emphasized. The APEX-1000 tests demonstrate that the AP1000 passive safety-related systems successfully combine to provide a continuous removal of core decay heat and the reactor core remains covered with considerable margin for all small-break LOCA events.

• Nuclear Engineering and Technology
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• 제53권3호
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• pp.793-803
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• 2021

The small PWR has been paid more and more attention due to its diversity of application and flexibility in the site selection. However, the large core power density, the small containment space and the rapid accident progress characteristics make it difficult to control the containment pressure like the traditional PWR during the LOCA. The pressure suppression system has been used by the BWR since the early design, which is a suitable technique that can be applied to the small PWR. Since the configuration and operating conditions are different from the BWR, the pressure suppression system should be redesigned for the small PWR. Conducting the experiments on the scale down test facility is a good choice to reproduce the prototypical phenomena in the test facility, which is both economical and reasonable. A systematic scaling method referring to the H2TS method was proposed to determine the geometrical and thermohydraulic parameters of the pressure suppression containment response test facility for the small PWR conceptual design. The containment and the pressure suppression system related thermohydraulic phenomena were analyzed with top-down and bottom-up scaling methods. A set of the scaling criteria were obtained, through which the main parameters of the test facility can be determined.

• Nuclear Engineering and Technology
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• 제53권4호
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• pp.1345-1356
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• 2021

Damage to nuclear power plants causes human casualties and environmental disasters. There are electrical facilities that control safety-related devices in nuclear power plants, and seismic performance is required for them. The 2016 Gyeongju earthquake had many high-frequency components. Therefore, there is a high possibility that an earthquake involving many high frequency components will occur in South Korea. As such, it is necessary to examine the safety of nuclear power plants against an earthquake with many high-frequency components. In this study, the shaking table test of electrical facilities was conducted against the design earthquake for nuclear power plants with a large low-frequency components and an earthquake with a large high-frequency components. The response characteristics of the earthquake with a large high-frequency components were identified by deriving the amplification factors of the response through the shaking table test. In addition, safety of electrical facility against the two aforementioned types of earthquakes with different seismic characteristics was confirmed through limit-state seismic tests. The electrical facility that was performed to the shaking table test in this study was a motor control center (MCC).

• 한국지리정보학회지
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• 제19권1호
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• pp.167-179
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• 2016

최근 범지구적으로 증가하는 이상기후에 의해 SOC 시설물 안전이 지속적으로 위협받고 있다. 재난대응을 위해서는 피난 대피 경로 제시 등과 같은 신속한 의사결정이 필요하며 이는 재난 재해 정보 및 SOC 시설물 정보가 융 복합된 시공간적 정보가 활용되어야 한다. 이러한 정보는 정부 및 유관기관에서 분산적으로 수집되고 있어, 통합적 관리가 이루어지지 않고 있는 실정이다. 신속한 재난대응을 위해서는 분산 수집 관리되고 있는 재난 재해 정보의 통합관리와 SOC 시설물에 대한 안전도와 피해도 등의 정보 생성이 필요하다. 또한 재난 재해 정보 특성상 시공간적 융합이 필요하기 때문에, 관련 정보를 통합한 재해대응 의사결정 지원을 위한 인벤토리 구축이 필요하다. 본 연구에서는 신속한 재난대응의사결정 지원을 위한 시설물 중요도 위험도 피해액 인벤토리 구축 방안을 제시한다. 본 연구를 통해 분산 관리 되고 있는 재난 재해 및 SOC 시설물 관련 데이터를 수집하여 표준화 하고, 시설물의 중요도 위험도 피해액 산정에 필요한 통합 정보를 제공 할 수 있다. 향후 제안된 시스템을 통해 선제적 재난 대응을 위한 의사결정 도구로 활용할 수 있을 것으로 판단된다.

• 한국방재안전학회논문집
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• 제7권1호
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• pp.35-42
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• 2014

본 연구는 재난환경 변화에 대응한 인적재난 R&D 중장기 로드맵 수립 기획에 관한 것으로서, 인적재난 안전기술 분야의 기술개발 투자 확대 방안 및 관련분야 선진국 대비 기술수준 격차해소를 위한 전략 제시, 인적재난안전기술개발 사업의 차세대대응기술 예측을 통한 사업 고도화, 중장기 로드맵 및 중점추진전략 도출, 중점 추진전략에 따른 주요 추진사업 및 세부추진과제 RFP 도출 등의 방안을 제시하였다. 주요 성과로서, 인적재난안전기술개발 중장기 투자 확대, 미래 인적재난 발생 가능성 예측을 통한 향후 재난대응 환경 변화와 안전관리 정책관련 패러다임 예측 및 효율적 대응, 인적재난안전기술 개발 중장기 로드맵을 통해 인적재난기술의 가치향상과 미래도약 기반강화 등이 기대된다.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2017년도 추계학술발표회
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• pp.140-140
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• 2017

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2017년도 추계학술발표회
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• pp.141-141
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• 2017

• 한국방재안전학회논문집
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• 제6권3호
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• pp.49-57
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• 2013

본 연구에서는 재난환경변화에 대응하여 인적재난 중장기 계획과 로드맵 수립을 기획하기 위하여 국내외 인적재난 안전기술 개발동향을 분석하여 중장기 로드맵을 제시하였다. 최근 국내에서는 재난환경에 연관된 사회환경, 생활환경, 국내외 정부부처 대응 등의 급변화 의하여 인적재난 연구개발 중장기 로드맵 수립의 필요성이 높아지고 있다. 미국은 국가재난 대응계획(NRF)과 국가사건사고관리시스템(NIMS)과 인적재난별 대응 시나리오 등에 의하여 기반을 구축하여 체계적인 연구를 진행하고 있으며, 일본은 년도별 방재백서의 연구개발 계획 등에 의거하여 재해대응 연구개발이 진행되고 있으며, 국내에서는 소방방재청과 국립재난안전연구원이 협력하여 인적재난 분야에 대한 연구과제를 진행하고 있다. 본 연구에서는 인적재난 연구개발 중장기 로드맵을 제시하여, '인명 및 재산피해를 최소화' 하고, 국가적 인적재난 분야 연구개발체계를 정립하고, 나아가 미래 인적재난환경 급변화에 대한 대책을 제시하였다.