• 월간산업보건
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• s.191
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• pp.4-10
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• 2004

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.11 no.2
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• pp.161-168
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• 2001

The types of exposure data needed in an industry-based study depend on the diseases of interest and the study design to be used. The best situation occurs when we have quantified personal exposure estimates for the agents of interest, the least informative case occurs when we have only knowledge of the fact of employment in a plant, industry, or trade where exposure probability is high. Exposure information for most industry-based studies falls somewhere between these tow extremes. Job exposure matrices(JEM) are designed to link information on occupation with information on exposure to specific workplace hazards. Some forms of systematic error of bias may be less likely to occur in studies that utilize job-exposure matrices to indirectly infer exposures from job titles than in studies that assess exposures by asking subjects about their past exposure. JEM can be used effectively in industry-based studies for historic cohort studies, case-control study to assist with the retrospective assessment of occupational exposures among workers whose individual exposure histories are unavailable. JEM generally consist of a computerized database that links information about job categories and likely exposures. These two major axes may be stratified by calendar time. This article reviews the design of JEM in support of industry-based studies. Specific matrices may find broader applicability along with the increasing availability of detailed hygienic data.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.15 no.10 s.89
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• pp.969-976
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• 2004

The wide and growing use of cellular phones has raised the question about the possible health risks associated with radio-frequency electromagnetic fields. It would be helpful for phone users to blow the exposure levels during cellular phone use. But it is very difficult to recognize the amount of exposure, because measuring accurate level of RF is a difficult matter. In this study, we developed a model to estimate the exposure level and the individual risk of exposure by utilizing the available informations that we can get. We used such parameters as usage time a day, total using period, distance between cellular phone and head, slope of cellular phone, hands-free usage, antenna pulled out or not SAR(Specific Absorption Rate) of cellular phone, and flip or folder type. We proposed a model presenting individual risk of RF exposure from level 0 to 10 by using a neural network.

• Journal of Soil and Groundwater Environment
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• v.13 no.6
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• pp.62-71
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• 2008

Soil quality standards (SQS) are necessary to protect the human health and soil biota from the exposure to soil pollutants. The current SQS in Korea contain only sixteen substances, and it is scheduled to expand the number of substances. Chemical ranking and scoring (CRS) system is very effective to screen the priority chemicals for the future SQS in terms of their toxicity and exposure potential. In this study, several CRS systems were extensively compared to propose the assessment factors that required for the screening of soil pollutants The CRS systems considered in this study include the CHEMS-1 (Chemical Hazard Evaluation for Management Strategies), SCRAM (Scoring and Ranking Assessment Model), EURAM (European Union Risk Ranking Method), ARET (Accelerated Reduction/Elimination of Toxics), CRSKorea, and other systems. The additional assessment factors of CRS suitable for soil pollutants were suggested. We suggest soil adsorption factor as an appropriate factor of CRS system to consider chemical transport from soil to groundwater. Other factors such as soil emission rate and cases of accident of soil pollutants were included. These results were reflected to screen the priority chemicals in Korea, as a part of the project entitled ‘Setting the Priority of Soil Contaminants'.

• Journal of the Mineralogical Society of Korea
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• v.28 no.3
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• pp.233-244
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• 2015

In order to study the phase transformation of pyrite and to determine the maximum Fe leaching factors, pyrite samples were an electric furnace and microwave oven and then ammonia leaching was carried out. The rim structure of hematite was observed in the sample exposed in an electric furnace, whereas a rim structure consisting of hematite and pyrrhotite were found in the microwave treated sample. Numerous interconnected cracks were only formed in the microwave treated sample due to the arcing effect, and these cracks were not found in the electric furnace treated sample. Under XRD analysis, pyrite and hematite were observed in the electric furnace treated sample, whereas pyrite, hematite and pyrrhotite were found in the microwave treated sample. The results of the pyrite sample leaching experiments showed that the Fe leaching was maximized with the particle size of -325 mesh, sulfuric acid of 2.0 M, ammonium sulfate of 1.0 M, and hydrogen peroxide of 1.0 M. The electric furnace and microwave treated samples were tested under the maximum leaching conditions, the Fe leaching rate was much greater in the microwave treated sample than in the electric furnace treated sample and the maximum Fe leaching time was also faster in the microwave treated sample than in the electric furnace treated sample. Accordingly, it is expected that the microwave heating can enhance (or improve) Fe leaching in industrial minerals as well as pyrite decomposition in gold ores.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.3
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• pp.2089-2099
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• 2015

This study examined the relationships between the blood heavy metal (Pb, Hg and Cd) concentration and exposure-related factors. The subjects were 2,042 (male: 953, female: 1,089) who were recruited through a National Health and Nutrition Examination Survey. Differences in the concentrations of mercury were observed in males, whereas females showed differences in lead and cadmium. Analyses of the blood concentrations according to body mass index and waist circumference showed significantly higher concentrations of mercury. In males, high-density lipoprotein cholesterol of dyslipidemia was higher than normal in the blood lead concentration. In females, low-density lipoprotein cholesterol of dyslipidemia was higher than normal in the blood lead concentration. The blood lead and cadmium concentrations of male smokers was higher than non-smokers, and cadmium showed the same results in females. The blood lead levels were higher in male alcohol consumers than non-drinkers. The blood concentrations of mercury and cadmium showed significant differences according to household income. Blood concentrations of heavy metals were closely related to exposure-related factors, and age, smoking, drinking alcohols, obesity, hyperlipidemia, and household income were found to be relevant.

• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.125-125
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• 2018

충청남도는 2015년에 극심한 가뭄을 겪으며 보령댐은 역대 최저 저수율을 기록하고 128일간 제한급수를 시행한 바 있다. 가뭄은 농작물 피해, 인적 피해뿐 아니라 사회경제적인 피해 또한 야기하지만 강수량과 가용수자원양만을 고려하는 기존의 가뭄 위험 지수들은 물리적인 피해만 반영한다는 한계점을 갖는다. 본 연구는 이러한 한계점을 극복하기 위해 기존 가뭄 지수에 지역적 특성을 반영할 수 있는 사회경제적 인자와 가뭄 적응능력 인자들을 함께 반영하는 가뭄 위험 지수를 개발하는 것을 목적으로 한다. 위험을 산정하기 위해 International Panel on Climate Change(IPCC)는 재해, 노출, 취약성으로 구분하였고, Organisation for Economic Co-operation and Development(OECD)는 인과관계 구성의 체제를 강조하며 Pressure-State-Response(P-S-R) 프레임워크를 개발한 바 있으며, World Risk Index(WRI)는 노출과 취약성으로 산출하였다. 본 연구에서 개발된 가뭄 위험 지수는 P-S-R 체제의 인과관계 구조를 참고하여 재해(hazard), 노출(exposure), 적응능력(capacity)으로 구분하였다. 재해는 기상학적 가뭄을 평가하기 위한 요소로서 SPI 기법을 통해 산정되고 노출은 가뭄의 피해 대상을 의미하여 지역별 용수 수요량을 사용하였다. 적응능력은 가뭄 피해를 줄일 수 있는 지역적 특성을 나타내며 사회적 능력과 공학적 능력으로 구분하여 산정하였다. 사회적 능력은 개인의 재정능력, 공무원 수 등이 포함되며 공학적 능력은 댐 현황, 지하수 이용현황, 하천시설 현황이 포함된다. 본 연구 결과와 2015년 가뭄을 비교함으로써 개발된 가뭄 위험 지수의 적합성을 확인하였으며 이를 통해 지역별 취약성 평가를 할 수 있었다.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.327.2-327.2
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• 2014

CIGS박막 태양전지의 온도에 의한 효율과 전기적 특성 변화를 알아보기 위해 $25^{\circ}C$, $50^{\circ}C$, $100^{\circ}C$, $150^{\circ}C$, $200^{\circ}C$에서 각각 100시간을 노출시킨 후 전기적인 특성들을 측정하여 초기 값들과 비교하였다. 태양전지의 온도 스트레스에 의한 특성 및 파라미터들의 변화들을 확인하기 위해 Light I-V와 Minority Carrier의 Lifetime을 측정하여 비교 분석하였다. 실험에 사용한 소자의 초기 파라미터들은 $25^{\circ}C$에서 측정하였고, 단락전류 11mA, 개방전압 0.64V, 곡선인자 60.49%, Lifetime 10.7s 효율 9.17%이다. 각 온도별 노출에 대해 CIGS박막 태양전지의 효율은 $50^{\circ}C$, $100^{\circ}C$에서는 초기 값과 비슷하였고, $150^{\circ}C$, $200^{\circ}C$에서 초기 값 대비 54%, 84% 감소 특성을 보였다. 단락전류는 $50^{\circ}C$, $100^{\circ}C$, $150^{\circ}C$에서는 크게 변화하는 모습이 나타나지 않았고 $200^{\circ}C$에서 63% 감소하였다. 개방전압, 곡선인자, Lifetime은 효율과 마찬가지로 $150^{\circ}C$, $200^{\circ}C$에서 감소하는 모습이 나타났다. $150^{\circ}C$, $200^{\circ}C$에서 개방전압이 9.3%, 18.7%, 곡선인자는 45.8%, 56.3%정도 감소하였다. Lifetime은 64.4%, 80.1%정도 감소하였다. 이 실험을 통해 개방전압과 곡선인자, Minority Carrier의 Lifetime이 일정 온도부터 온도의 영향을 받아 감소하고, 그 영향으로 효율이 감소하게 되는 것을 확인하였다.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.381-381
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• 2012

가뭄은 이수에 영향을 주는 피해 중 가장 대표적인 예라고 할 수 있다. 가뭄은 장기간에 걸쳐서 강수량이 부족하거나, 지속적인 일사량의 증가로 인하여 수문학적 물 균형이 깨어져서 물 부족 현상이 발생하는 것을 의미한다. 우리나라는 2001년에 기상관측 이래 때 이른 무더위와 극심한 가뭄으로 강원도지역을 중심으로 전국적인 피해를 입었다. 미국 해양기상청(NOAA, National Oceanic and Atmospheric Administration)에서는 20세기 최대의 자연재해 중 5위권내에 가뭄으로 인한 재해가 무려 4개나 랭크된바 있다. 하지만 우리나라에서는 홍수 등에 대비해서는 수해방지종합대책등 사전대책을 마련하여 방지대책을 세우지만, 가뭄에 대해서는 종합적인 사전예방대책보다는 복구 위주로 진행되고 있다. 이로 인해 가뭄으로 인한 피해상황 및 피해유발인자의 파악이 어렵고 객관적으로 표현할 수 있는 지표도 명확하지 않기 때문에 이에 대한 체계적인 연구가 시급한 실정이다(이주헌과 이길재, 2006). 본 연구에서는 가뭄으로 인한 피해유발인자를 파악하기 위하여 UNDP(United Nations Development Programme, 2004)에서 제공하는 물리적 노출(Physical Exposure)정도를 1990년~2007년간의 유역별 월강수량 자료를 이용하여 가뭄의 발생 빈도별로 산정한 후에 가뭄으로 인한 농작물피해 및 제한급수에 영향을 미치는 인자들에 대하여 분석을 실시하였다.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 1998.12a
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• pp.69-69
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• 1998