• Title/Summary/Keyword: Hazardous area

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Human Health Risk based Priority Ranking for Hazardous Air Pollutants (대기중 유해 화학 물질의 인체 위해도 우선순위 선정 연구)

  • Park Hoa-sung;Kim Ye-shin;Lee Dong-soo;Shin Dong-chun
    • Environmental Analysis Health and Toxicology
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    • v.19 no.1
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    • pp.81-91
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    • 2004
  • Although it is suggested that risk -based management plan is needed to manage air pollution effectively, we have no resources enough to evaluate all aspects of substances and set priorities. So we need to develop a logical and easy risk-based priority setting method. However, it if impossible that only one generic system that is consistent with all the use is developed. In this study, we proposed a human health risk based priority-setting method for hazardous air pollutants, and ranked priorities for this method. First of all, after investigating previous chemical ranking and scoring systems, we chose appropriate indicators and logics to goal of this study and made a chemical priority ranking method using these. As results, final scores in priority ranking method were derived for 25 substances, and ethylene oxide, acrylonitrile and vinyl chloride were included in high ranks. In addition, same substances were highly ranked when using default values like when using no default, but the scores of hydrofluoric acid and ryan and compounds were sensitive to default values. This study could be important that priorities were set including toxicity type and quality and local inherent exposure conditions and we can set area-specific management guidelines and survey plans as a screening tool.

A Study on the Risk Assessment and Mitigation Plan about Fire Explosion of n-Pentane in EPS Process (EPS공정에서 발생하는 n-Pentane의 화재폭발에 대한 위험성평가 및 위험성 완화 대책에 관한 연구)

  • Seo, Min Su;Kim, Ki Sug;Kim, Bo Min;Kang, Dong Cheon;Kang, Kil Jae;Chon, Young Woo
    • Korean Journal of Hazardous Materials
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    • v.6 no.2
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    • pp.39-46
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    • 2018
  • 최근 전자제품 생산업체에서 EPS를 직접생산하게 되면서 EPS 공정이 증가하고 있다. EPS에는 펜탄이 포함되어 있으며, 펜탄은 하이브리드 혼합물로 구분할 수 있어 높은 화재폭발의 위험성을 가지고 있다. 각 공정별 펜탄의 누출률은 발포기, 사일로실, 저장실 순이나 발포기의 경우 일반적으로 밀폐되어 있으므로 사일로 실이 가장 화재폭발 위험성이 높다고 판단하였다. 사일로실의 누출률 중 70%는 사일로 상단을 통해 누출되며, 사일로 상단을 통해 누출되는 펜탄의 거동을 분석하여 사일로실 위험성 완화대책을 수립하였다. 1. 폭발위험구역 2종으로 관리, 2. 사일로상단 50cm이내 환기설비 설치 또는 Push-Pull 구조의 환기설비설치, 3. 사일로 하단 1.4m이내에 가스감지기 설치, 4. 60%이상의 습도유지

Residue characteristics of hexaconazole and chlorothalonil in several fruits (과일의 형태적 특성에 따른 농약의 잔류성과 분포)

  • Lee, Hee-Dong;Kyung, Kee-Sung;Kwon, Hye-Young;Ihm, Yang-Bin;Kim, Jin-Bae;Park, Seung-Soon;Kim, Jang-Eok
    • The Korean Journal of Pesticide Science
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    • v.8 no.2
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    • pp.107-111
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    • 2004
  • The study was carried out to investigate the pesticide residual characteristics in peaches, pear and grape. Pesticide residue patterns were remarkably different because of major factors affecting the pesticide residue patterns such as ratios of surface to weight, surface matrices, cultivations, sizes, increase rate of weight, and varieties of fruits, etc.. Pesticide residue levels in grape appeared higher than those in peaches and pear, because the pesticide solution sprayed was infiltrated and accumulated between grape granules. The matrices composing of fruit surface and the ratios of surface area to weight on fruits seemed to playa key role for determining the pesticide residual characteristics in fruits.

A Study on the Impact Scope from Hazardous Chemicals Leakage in Jeju Area - Focused on hydrogen fluoride - (제주지역 유해화학물질 누출사고 시 영향범위에 관한 연구 - 불화수소 중심으로 -)

  • Lim, Chaehyun;Doh, Sang Hyeun;Kim, Changyoung
    • Journal of the Korean Society of Urban Environment
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    • v.18 no.4
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    • pp.495-502
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    • 2018
  • In this study, the AERMOD air diffusing model was used to estimate the range of influence of Hazardous chemicals (hydrogen fluoride) in case of small accidents in Jeju area. The impact scope were in the order of Seogwipo Fire Station, Dongbu Fire Station, Jeju Fire Station, and Seobu Fire Station. Seasonal orders were summer, spring, autumn and winter. The correlation between the meteorological factors shows a strong positive correlation with the wind speed of 0.998 and has a negative correlation with the temperature of -0.463. Through the linear regression analysis, we could estimate the equation of Impact scope = 13.922WS (Wind Speed) - 5.195 and the reliability ($R^2$) was as high as 0.995.

Determining Whether to Enter a Hazardous Area Using Pedestrian Trajectory Prediction Techniques and Improving the Training of Small Models with Knowledge Distillation (보행자 경로 예측 기법을 이용한 위험구역 진입 여부 결정과 Knowledge Distillation을 이용한 작은 모델 학습 개선)

  • Choi, In-Kyu;Lee, Young Han;Song, Hyok
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.25 no.9
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    • pp.1244-1253
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    • 2021
  • In this paper, we propose a method for predicting in advance whether pedestrians will enter the hazardous area after the current time using the pedestrian trajectory prediction method and an efficient simplification method of the trajectory prediction network. In addition, we propose a method to apply KD(Knowledge Distillation) to a small network for real-time operation in an embedded environment. Using the correlation between predicted future paths and hazard zones, we determined whether to enter or not, and applied efficient KD when learning small networks to minimize performance degradation. Experimentally, it was confirmed that the model applied with the simplification method proposed improved the speed by 37.49% compared to the existing model, but led to a slight decrease in accuracy. As a result of learning a small network with an initial accuracy of 91.43% using KD, It was confirmed that it has improved accuracy of 94.76%.

A study for the Improvement of Sanitary Condition in Korean style-restaurant in Seoul city area (I) - Evaluation on sanitation of working environment and facilities for the kitchen- (한식 제공 음식업소의 위생 및 시설 조사 연구 (I) -작업환경 위생 및 조리설비 평가-)

  • Kye, Seung-Hee;Moon, Hyun-Kyung;Chung, Hae-Rang;Hwang, Seong-Hee;Kim, Wu-Seon;Moon, Hae-Yeun
    • Journal of the Korean Society of Food Culture
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    • v.9 no.5
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    • pp.457-465
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    • 1995
  • The purpose of the present study is to identify potentially hazardous factors which can contribute to the outbreak of foodborne disease and to represent more practical management methods in terms of environmental sanitation and facilities for the kitchen. 230 Korean-style restaurants in Seoul were assessed and analyzed by the restaurant total area. Facilities and sanitary check-lists were developed to evaluate the facilities and sanitary conditions of sampled restaurants. The sanitary condition of kitchen, guest room and other area were assessed by the sanitary score. The basic cooking machinery and utensil were properly facilitated but automation machinery were equiped below 10% sampled restaurants. The kitchen area were not properly sufficient to total area. Sanitary condition of kitchen, guest room, cooking appliance and stored foods were evaluated as the unsatisfactory state with potentially hazardous. Concrete guidelines should be made in terms of following item; establishment for the kitchen space expansion, facilities for the improvement of the working environment and sanitary condition of foods cooked. Additionaly, it need to practice the effective education and training program for the foodservice manager and employees.

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The Intrinsic Safety Evaluation of Solar Photovoltaic Cell (태양전지셀의 본질안전 방폭성능 평가)

  • Lee, Chun-Ha;Jee, Seung-Wook;Kim, Si-Kuk
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.25 no.7
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    • pp.49-54
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    • 2011
  • Now the world will regulate the CO2 emission due to environmental issues. For an alternative plan photovoltaic system is watched. So, photovoltaic system is trend of big city and it is mandatory for renovation of construction. Oil & gas filling station existed in city is suitable to found the photovoltaic system. But the general photovoltaic system in oil & gas filling station is difficult to found because it is classified into hazardous area. This paper evaluates intrinsic safety evaluation of solar cell for making basic data to found for the photovoltaic system on hazardous area. The intrinsic safety characteristic is evaluated by short-circuit ignition test using IEC type spark ignition test apparatus and temperature rising test. The result of short-circuit ignition test, propane-air mixture gas is exploded on condition that 4 solar cells(9[V], 90[mA]) are connected serially under insolation 800[W/$m^2$]. So, if a larger solar module will be used at oil & gas filling station than we were tested, it needs explosion proof. As the result of rising temperature test, the temperature rising due to short circuit is not so much, but when the temperature rises due to radiant heat, it demands careful consideration for environmental influence.

Ignition and flame propagation in hydrogen-air layers from a geological nuclear waste repository: A preliminary study

  • Ryu, Je Ir;Woo, Seung Min;Lee, Manseok;Yoon, Hyun Chul
    • Nuclear Engineering and Technology
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    • v.54 no.1
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    • pp.130-137
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    • 2022
  • In the geological repository of radioactive nuclear waste, anaerobic corrosion can generate hydrogen, and may conservatively lead to the production of hydrogen-air layer. The accumulated hydrogen may cause a hazardous flame propagation resulting from any potential ignition sources. This study numerically investigates the processes of ignition and flame propagation in the layered mixture. Simple geometry was chosen to represent the geological repository, and reactive flow simulations were performed with different ignition power, energy, and locations. The simulation results revealed the effects of power and energy of ignition source, which were also analyzed theoretically. The mechanism of layered flame propagation was suggested, which includes three stages: propagation into the hydrogen area, downward propagation due to the product gas, and horizontal propagation along the top wall. To investigate the effect of the ignition source location, simulations with eight different positions were performed, and the boundary of hazardous ignition area was identified. The simulation results were also explained through scaling analysis. This study evaluates the potential risk of the accumulated hydrogen in geological repository, and illustrates the layered flame propagation in related ignition scenarios.