• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2017년도 공동학술발표회
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• pp.54-54
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• 2017

• 비파괴검사학회지
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• 제35권4호
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• pp.258-267
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• 2015

Eddy current testing is widely used for inspecting steam generator tubing in nuclear power plants (NPPs). The inspection technique for steam generator tubing in NPPs should be qualified in accordance with examination guidelines. When the components of a qualified system such as eddy current tester, probe, and data analysis program, are changed, the equivalency of the modified system to the originally qualified system must be verified. The eddy current tester is the most important part of an eddy current testing system because it excites and transmits alternating currents to the probe, receives coil impedance of the probe and generates signals for anomalies. The Korea Hydro & Nuclear Power Co., Ltd. (KHNP) developed an eddy current testing system with an eddy current tester and data acquisition-analysis program for inspecting the steam generator tubing in NPPs; this system can be used for an array probe and as a bobbin and rotating probes. The equivalency assessment for the currently developed system was carried out, and we describe the results in this paper.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 1996년도 학술발표회
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• pp.37-42
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• 1996

The assessment of catastrophic accidents such as BLEVE, vapor cloud explosion, and toxic material releases in the chemical process industries(CPI) shall be carried out according to the Requirement of PSM/SMS enforced by Korea Government Agencies, but reasonable models are not proposed for the practical application. The traditional models, TNT Equivalency Model, are well-known and helpful for the assessment of vapor cloud explosion. However, the estimated-damage-area using the traditional model has much more deviations comparing to the real damage caused by vapor cloud explosion suffered before. These are why an expert system for the assessment of vapor cloud explosion has been developed, which is based on theoretical, statistical and experimental data, and it would be helpful for CPI to evaluate the damage-area in case of vapor cloud explosion.

• 환경영향평가
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• 제14권6호
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• pp.443-453
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• 2005

For the purpose of the comparative environmental estimation of the incineration processes for domestic wastes, environmental impacts for several incineration processes for one ton of domestic wastes have been estimated by employing life cycle assessment as the environmental impact assessment method. The scheme of minimum production of environmental pollutants has been considered for three different incineration processes. The evaluation for latent influence on environment was carried out by using CML(Center of Environmental Science) method which was developed by University of Leyden in Netherlands based on the equivalency factor suggested by Korea Accreditation Board. The result of life cycle assessment has showed that the total cost analysis according to the amount of incinerating waste was dependent on the operating conditions of incineration process. In addition, the annual running cost for the incineration of one ton of wastes was estimated to be negatively dependent on the amount of wastes. The degree of environmental pollution was mainly due to the kinds of the wastes rather than by the amount of wastes.

• 한국가스학회지
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• 제4권4호
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• pp.50-57
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• 2000

가연성 증기 또는 가스 누출로 인해 발생하는 증기운 폭발은 엄청난 과압을 생성시켜 사고 영향이 매우 크기 때문에 공정 중에 잠재하고 있는 사고의 위험요소를 발굴하여 제거하여야 한다. 이를 위해서는 사고 결과 영향평가가 선행되어야 한다. 이러한 평가를 수행하기 위해서는 신뢰할만한 예측 도구(Tool)가 필요하다(13). 현재 여러 가지 사고결과 피해예측 모델이 제시되어 활용되고 있는 바 이러한 예측 모델(TNT-Equivalency, TNO Hemispherical, TNO Multi-Energy, CFD)이 어느 정도 타당성이 있는지에 대한 검토가 필요하다. 따라서 본 연구에서는 증기운 폭발 위험성 정량화를 위해 사용된 각 모델을 비교 검토하여 여러 가지 모델의 가정 및 정확성을 알아보고 가장 타당성 있는 모델을 선정 하고자 한다.

• 한국안전학회지
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• 제14권2호
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• pp.109-115
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• 1999

The release of gas from the LPG storage tank by the rupture or leakage can occure explosion and this causes serious damage to people and structures. In this study, the explosion effect and damaging distance were measured for the LPG cloud explosion to perform the quantitative risk assessment for the PSM, and the effective parameters on the explosion were found. The gas dispersion and mass contaminant in the explosion limits were calculated by using DEGADIS, and it was converted to TNT equivalency and damaging distance. As a result, the wind speed was the most effective parameter on the diffusion rate and TNT equivalency, and the damaging distance were increased with decrease of wind speed and surface roughness.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2001년도 봄 학술발표회 논문집
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• pp.3-14
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• 2001

This study introduces the framework of the mutual recognition project of APEC Engineer and also tries to find out what we, Korean engineers have to do with this project. The mutual recognition framework consists of 2 main frameworks ; the substantial equivalence framework and the mutual exemption framework. The participating Economies have discussed and agreed on the framework of the substantial equivalency and have been producing APEC Engineers from the 1st, Nov 2000 based on this agreement. However, more discussions will be required from now on in order to finalize the mutual exemption agreement, even though there have been a lot of discussions including the workshop for the regulatory authority for the last 5 years. Here we have to study and find out what we have to do with this project and prepare for the bilateral agreements and the Coordinating Committee meeting to be held in Hongkong in Oct this year.

• 화약ㆍ발파
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• 제40권3호
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• pp.44-53
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• 2022

본 연구에서는 증기운 폭발 시 발생하는 폭풍파의 과압을 결정하는데 사용되는 폭발 예측 모델인 TNT등가법, 다중에너지법, Baker-Strehlow-Tang(BST)법의 적용성을 평가하였다. 원룸 주택과 상가가 밀집한 지역 내에 설치된 2000 kg 용량의 프로판 저장 용기에서 누출된 프로판이 증기운 폭발을 일으키는 것을 가정하였다. TNT등 가법을 적용하여 계산한 2000 kg의 프로판과 등가인 TNT의 질량은 4061 kg인 것으로 나타났다. TNT등가법, 다중에너지법, BST법으로 구한 거리에 따른 과압의 변화 양상에 따르면 폭원으로부터 100 m 이내 지점에서는 과압의 감소가 급격하고, 대체적으로 TNT등가법과 BST법으로 구한 과압의 크기가 유사한 것으로 나타났다. 실제 증기운 폭발 사례에서 관찰된 과압과 TNT등가법, 다중에너지법, BST법을 적용하여 구한 과압을 비교한 결과 BST법이 가장 잘 맞는 것으로 나타났다. 각 폭발 예측 모델로 구한 거리에 따른 과압을 구조물 손상 기준과 비교한 결과 폭원으로부터 90 m 이내에 위치하는 구조물은 반파 이상의 피해를 볼 것으로 평가되었고, 600 m 이격된 구조물도 유리창이 파손되는 피해가 있을 것으로 예측되었다.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2002년도 Current Trends in Toxicological Sciences
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• pp.136-136
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• 2002

Polycyclic aromatic hydrocarbons(PAHs) vary in their carcinogenic potencies. The more potent PAHs carcinogens are 3-methylcholantheren and 7, 12- dimethyl benzo(a)anthracene, while dibenzo(a, c)anthracene has very little carcinogenic activity. Risk assessment of chemical mixture containing various congeners which toxic potency are each different, are conducted using toxic equivalency factors(TEFs).(omitted)

• Asian Journal of Atmospheric Environment
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• 제7권2호
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• pp.72-84
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• 2013

In the study, pollution levels of indoor polycyclic aromatic hydrocarbons (PAHs) in public facilities (vapor phase or particulate phase) were evaluated, and a health risk assessment (HRA) was carried out based on exposure scenarios. Public facilities in Korea covered by the law, including underground subway stations, funeral halls, child care facilities, internet cafes (PC-rooms), and exhibition facilities (6 locations for each type of facility, for a total of 48 locations), were investigated for indoor assessment. For the HRA, individual excess cancer risk (ECR) was estimated by applying main toxic equivalency factor (TEF) values suggested in previous studies. Among the eight public facilities, internet cafes showed the highest average $PM_{2.5}$ concentration at $110.0{\mu}g/m^3$ (range: $83.5-138.5{\mu}g/m^3$). When assuming a risk of facility exposure time based upon the results of the surveys for each public facility, the excess cancer risk using the benzo(a)pyrene indicator assessment method was estimated to be $10^{-7}-10^{-6}$ levels for each facility. Based on the risk associated with various TEF values, the excess cancer risk based upon the seven types cancer EPA (1993) and Malcolm & Dobson's (1994) assessment method was estimated to be $10^{-7}-10^{-5}$ for each facility. The excess cancer risk estimated from the TEF EPA (2010) assessment was the highest: $10^{-7}-10^{-4}$ for each facility. This is due to the 10-fold difference between the TEF of dibenzo(a,e)fluoranthene in 2010 and in 1994. The internet cafes where smoking was the clear pollutant showed the highest risk level of $10^{-4}$, which exceeded the World Health Organization's recommended risk of $1{\times}10^{-6}$. All facilities, with the exception of internet cafes, showed a $10^{-6}$ risk level. However, when the TEFs values of the US EPA (2010) were applied, the risk of most facilities in this study exceeded $1{\times}10^{-6}$.