충청,전라지역 산업단지 주변지역에서의 벤젠 인체 위해성 평가

장용철 ( Yong Chul Jang ),이성우 ( Sung Woo Lee ),신용승 ( Yong Seung Shin ),김희갑 ( Hee Kap Kim ),이종현 ( Jong Hyun Lee ) 한국환경영향평가학회 2011 환경영향평가 Vol.20 No.4

This research studied human health risk assessment of benzene from industrial complexes of Chungcheong Province (Seosan industrial complex) and Jeonla Province (Iksan industrial complex and Yeosoo industrial complex). The residents near the industrial complexes areas can be often exposed to volatile organic compounds (e.g., benzene, toluene, xylenes) through a number of exposure pathways, including inhalation of the organic pollutant via various environmental matrices (air, water and soil), contaminated water, and soil intake. Benzene is well known to be a common carcinogenic and toxic compound that is produced from industrial and oil refinery complexes. In this study, a number of samples from water, air, and soil were taken from the residential settings and public school zones located near the industrial complex sites. Based on the carcinogenic risk assessment, the risk estimates were slightly above 1.0×10(-6) at all three industrial sites. According to deterministic risk assessment, inhalation was the most important route. The distribution of benzene in the environment would be dependent on vapor pressure, and the physical property influencing the extent of the potential risks. Noncarcinogenic risk assessment of benzene shows that the values of Hazard Index(HI) were much lower than 1.0 at all industrial complexes. Therefore, benzene was not a cause of concern in terms of non-carcinogenic risk posed to the residents near the sites. When compared to probabilistic risk assessment, the CTE(central tendency exposure) cancer risk values of deterministic risk assessment were close to the mean values predicted by the probabilistic risk assessment. The RME(reasonable maximum exposure) values fell within the range of 95% to 99.9% estimated by the probabilistic risk assessment. Since the values of carcinogenic risk assessment were higher than 1.0×10(-6), further detailed monitoring and refined risk assessment for benzene may be warranted to estimate more reliable and potential inhalation risks to receptors near the industrial complexes.

대전 1 공단 및 2 공단지역의 대기중 독성 금속에 대한 확률론적 위해도 평가

이진홍 대한보건협회 2000 대한보건연구 Vol.26 No.1

The research centered on a probabilistic risk assessment of toxic metals for ambient air in Taejon Industrial Complex 1 & 2. Airborne concentrations of each toxic metal for the assessment were obtained from about 2-year sampling and analysis in the complex. The long-term arithmetic means of human carcinogens, i. e., arsenic, hexavalent chromium and nickel subsulfide were 5.53, 2.16, and 3.46 ng/m^3 while the means of probable human carcinogens such as beryllium, cadmium and lead were 0.08, 2.35, and 293.29 ng/m^3, respectively. Based on a probabilistic risk assessment, the 50th~95th percentile cancer risks for men and women were 2.8×10 exp (-5)∼9.6×10 exp (-5), and 2.5×10 exp (-5)∼8.5×10 exp (-5), respectively. These percentile risks did not exceed de minimis risk level of 10^-4 based on the 95th percentile risk. This study also showed that probabilistic risk assessment can provide a more complete assessment of risk and more useful information to risk manager and the public. However, uncertainty remains and improved Korean probabilistic density functions (PDF) are needed for factors such as inhalation rate, exposure frequency, cancer potency factors and reference doses.

Collision risk assessment of occluded vehicle based on the motion predictions using the precise road map

Lee, Minchul,Sunwoo, Myoungho,Jo, Kichun Elsevier 2018 Robotics and autonomous systems Vol.106 No.-

<P><B>Abstract</B></P> <P>A perception system based on vehicle detection sensors, which are mounted on an ego vehicle, has restricted visibility because of blockage by obstacles. Estimating the risk of collision with moving vehicles in an occluded area is difficult because their locations and speeds cannot be detected. To address the occlusion problem, this paper proposes a probabilistic collision risk assessment method for a potential collision vehicle in an occluded area. The proposed method estimates the collision risk in three steps: occlusion boundary modeling of perception, motion prediction of the potential collision vehicles, and probabilistic collision risk assessment. The first step models the occlusion boundary to classify the free space and the unknown region. In the second step, the moving path of each potential collision vehicle is predicted considering its future behavior. The final step estimates the collision probability with a potential collision vehicle based on the speed distribution of the vehicles on the road. We evaluate the proposed probabilistic collision risk assessment method in several occlusion scenarios with real traffic, including an alleyway, a merging lane, and blockage by a bulky vehicle.</P> <P><B>Highlights</B></P> <P> <UL> <LI> This paper proposes probabilistic collision risk assessment for invisible vehicles. </LI> <LI> The movements of invisible vehicles are predicted by precise road geometry map. </LI> <LI> Collision risk probability is assessed by predicted path and stochastic speed model. </LI> <LI> The algorithm was evaluated in several real traffic scenarios such as intersections. </LI> </UL> </P>

연구보문 : 수질환경 ; 농업용수를 공급하는 호소 수역 내 잔류 농약의 생태위해성평가: 위해지수방법과 확률론적 방법

이지호 ( Ji Ho Lee ),박병준 ( Byung Jun Park ),박상원 ( Sang Won Park ),김원일 ( Won Il Kim ),홍수명 ( Su Myung Hong ),임건재 ( Geon Jae Im ),홍무기 ( Moo Ki Hong ) 한국환경농학회 2011 한국환경농학회지 Vol.30 No.3

BACKGROUND: Pesticides concentration was monitored in 50 agricultural lakes, and ecological risk for aquatic organism was assessed using risk quotient (RQ) and probabilistic methods. METHODS AND RESULTS: Pesticides concentrations detected in 50 agricultural lakes during peak season (June and September) were in the range of 0.17~0.99 ?g/L. The RQ for algae and the other species 1was estimated to be 0.25 and below 0.01, indicating medium risk and no risk. Oxadiazon predominantly contributed to RQ value of 99% for algae, fishes, and amphibians. In terms of hazardous concentration at 5% of species (HC5), ecological risk quotients (ERQ) for oxadiazon ranged from 0.18~0.33, showing a medium risk level. Overall, the concentrations of pesticides were much lower than HC5 value. Probability of combined ecological risk for pesticides ranged from 1.82% to 2.41%. CONCLUSION(s): Combined ecological risk probability did not exceed the acceptable level of 5%, indicating no ecological risk for selected aquatic species. This study suggests that regular ecological risk assessment (ERA) will be required to protect and manage an agricultural lake. Not only ERA at screening level by comparing exposure with toxic effects for aquatic species also advanced ERA technique considering species in indigenous to Korea, chronic toxicity, pulse dose, fate, and environmental factors should be required.

Holistic Approach to Multi-Unit Site Risk Assessment: Status and Issues

김인석,장미숙,김성래 한국원자력학회 2017 Nuclear Engineering and Technology Vol.49 No.2

The events at the Fukushima Daiichi Nuclear Power Station in March 2011 point out, among other matters, that concurrent accidents at multiple units of a site can occur in reality. Although site risk has been deterministically considered to some extent in nuclear power plant siting and design, potential occurrence of multi-unit accident sequences at a site was not investigated in sufficient detail thus far in the nuclear power community. Therefore, there is considerable worldwide interest and research effort directed toward multi-unit site risk assessment, especially in the countries with high-density nuclearpower- plant sites such as Korea. As the technique of probabilistic safety assessment (PSA) has been successfully applied to evaluate the risk associated with operation of nuclear power plants in the past several decades, the PSA having primarily focused on single-unit risks is now being extended to the multi-unit PSA. In this paper we first characterize the site risk with explicit consideration of the risk associated with spent fuel pools as well as the reactor risks. The status of multi-unit risk assessment is discussed next, followed by a description of the emerging issues relevant to the multi-unit risk evaluation from a practical standpoint.

PRA RESEARCH AND THE DEVELOPMENT OF RISK-INFORMED REGULATION AT THE U.S. NUCLEAR REGULATORY COMMISSION

Siu, Nathan,Collins, Dorothy Korean Nuclear Society 2008 Nuclear Engineering and Technology Vol.40 No.5

Over the years, probabilistic risk assessment (PRA) research activities conducted at the U.S. Nuclear Regulatory Commission (NRC) have played an essential role in support of the agency's move towards risk-informed regulation. These research activities have provided the technical basis for NRC's regulatory activities in key areas; provided PRA methods, tools, and data enabling the agency to meet future challenges; supported the implementation of NRC's 1995 PRA Policy Statement by assessing key sources of risk; and supported the development of necessary technical and human resources supporting NRC's risk-informed activities. PRA research aimed at improving the NRC's understanding of risk can positively affect the agency's regulatory activities, as evidenced by three case studies involving research on fire PRA, human reliability analysis (HRA), and pressurized thermal shock (PTS) PRA. These case studies also show that such research can take a considerable amount of time, and that the incorporation of research results into regulatory practice can take even longer. The need for sustained effort and appropriate lead time is an important consideration in the development of a PRA research program aimed at helping the agency address key sources of risk for current and potential future facilities.

Improved Probabilistic Modeling of Wind Speed in the Context of Structural Risk Assessment

Jianjun Qin 대한토목학회 2018 KSCE JOURNAL OF CIVIL ENGINEERING Vol.22 No.3

The present paper aims to propose a new formulation of probabilistic model of wind speed in the context of structural risk assessment. The inconsistency between the probability distribution of different levels of wind speed, i.e. high speed and low and normal speed, is identified and analyzed at first. Considering the importance of the accurate probabilistic analysis of wind with high speed on the structural risk assessment, the boundary between the two parts would be identified from the solution to the proposed optimization problem; and correspondingly, the records will be separated. The probability distribution of the two parts would be identified respectively and they will be unified into one framework to facilitate the further risk analysis. Finally the procedure of the formulation in practice is provided. The proposed model will be applied to the probabilistic analysis of the wind speed at Shanghai Pudong based on its four-year data.

Swift Probabilistic Risk Assessment Model of Chemical Hazards in Food by Tiered Approach: A Case Study of Pesticide Residues in Packaged Red Pepper Powder

김현정,정아람,심유신 한국식품과학회 2013 Food Science and Biotechnology Vol.22 No.3

Development of a swift probabilistic risk assessment (sPRA) model is needed to obtain information on exposure to food hazards before performing complex full-scale risk assessment. A sPRA model was developed using a tiered approach, which uses qualitative information,quantitative analysis of focused hazards, and a Monte Carlo simulation. A case study was conducted on residual pesticides in red pepper powder using sPRA model. Of a wide range of pesticides, chlorpyrifos and cypermethrin were selected for sPRA modeling. As a result of the sPRA model simulation, the estimated dietary exposure to pesticide residue from the consumption of red pepper powder was below 0.04% of the acceptable daily intake (ADI) for the 95th percentile exposure. Risk of dietary exposure to hazards was quantitatively estimated by the sPRA model developed, and the risk of residual pesticide in red pepper powder in Korea was found to be very low.

PRA RESEARCH AND THE DEVELOPMENT OF RISKINFORMED REGULATION AT THE U.S. NUCLEAR REGULATORY COMMISSION

NATHAN SIU,DOROTHY COLLINS 한국원자력학회 2008 Nuclear Engineering and Technology Vol.40 No.5

Over the years, probabilistic risk assessment (PRA) research activities conducted at the U.S. Nuclear Regulatory Commission (NRC) have played an essential role in support of the agency’s move towards risk-informed regulation. These research activities have provided the technical basis for NRC’s regulatory activities in key areas; provided PRA methods, tools, and data enabling the agency to meet future challenges; supported the implementation of NRC’s 1995 PRA Policy Statement by assessing key sources of risk; and supported the development of necessary technical and human resources supporting NRC’s risk-informed activities. PRA research aimed at improving the NRC’s understanding of risk can positively affect the agency’s regulatory activities, as evidenced by three case studies involving research on fire PRA, human reliability analysis (HRA), and pressurized thermal shock (PTS) PRA. These case studies also show that such research can take a considerable amount of time, and that the incorporation of research results into regulatory practice can take even longer. The need for sustained effort and appropriate lead time is an important consideration in the development of a PRA research program aimed at helping the agency address key sources of risk for current and potential future facilities.

Risk-informed design optimization method and application in a lead-based research reactor

Jiaqun Wang,Qianglong Wang,Jinrong Qiu,Jin Wang,Fang Wang,Yazhou Li Korean Nuclear Society 2023 Nuclear Engineering and Technology Vol.55 No.6

Risk-informed approach has been widely applied in the safety design, regulation, and operation of nuclear reactors. It has been commonly accepted that risk-informed design optimization should be used in the innovative reactor designs to make nuclear system highly safe and reliable. In spite of the risk-informed approach has been used in some advanced nuclear reactors designs, such as Westinghouse IRIS, Gen-IV sodium fast reactors and lead-based fast reactors, the process of risk-informed design of nuclear reactors is hardly to carry out when passive system reliability should be integrated in the framework. A practical method for new passive safety reactors based on probabilistic safety assessment (PSA) and passive system reliability analyze linking is proposed in this paper. New three-dimension frequency-consequence curve based on risk concept with three variables is used in this method. The proposed method has been applied to the determination optimization of design options selection in a 10 MWth lead-based research reactor(LR) to obtain one optimized system design in conceptual design stage, using the integrated reliability and probabilistic safety assessment program RiskA, and the computation resources and time consumption in this process was demonstrated reasonable and acceptable.