• Title/Summary/Keyword: Uncertainty evaluation

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A Harmonized Method for Dose-response Risk Assessment Based on the Hazard & Risk Evaluation of Chemicals (HREC) According to the Industrial Safety and Health Act (ISHA) (산업안전보건법 상 유해성.위험성 평가제도 적용을 위한 양-반응 평가의 통일화 방안 연구)

  • Lim, Cheol-Hong;Yang, Jeong-Sun;Park, Sang-Yong
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.22 no.3
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    • pp.175-183
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    • 2012
  • Objectives: This study developed a harmonized method for risk assessment based on the Hazard & Risk Evaluation of Chemicals (HREC) according to the Industrial Safety and Health Act (ISHA). Methods: Three preliminary studies, performed during 2010 and 2011 by the Occupational Safety and Health Research Institute and three academic research groups, were compared. The differences in risk assessment, especially in the dose-response assessment method, were analyzed. A new harmonized method for dose-response assessment was suggested and its applicability for the HREC was examined. Results: Considering the various steps of each dose-response assessment, the equivalent steps in quantitative correction, uncertainty factor 2 (UF2) for intra-species uncertainty, and UF3 for the experimental period in the uncertainty correction were relatively high. Using our new method, the total correction values (quantitative correction plus uncertainty correction) ranged from 72~15,789 to 30~60, and the ratio of the threshold limit value (TLV) to the reference concentration decreased from 12.8~1900 to 5.4~11.8. Furthermore, when we performed risk characterization by our new method, hazard quotient (HQ) values for chloroethylene, epichlorohydrin, and barium sulfate became 3.0, 14.1, and 1.13 respectively, whereas three previous studies reported HQ values of 7.1, 4580, and 87.3 considering reasonable maximum exposure (RME) conditions. HQs of the three chemicals were calculated to be 0.6, 2.4, and 0.1 respectively, when compared to their TLVs. Conclusions: Our new method could be applicable for the HREC because the total correction values and the ratio of TLVs were within reasonable ranges. It is also recommended that additional risk management measures be applied for epichlorohydrin, for which the HQ values were greater than 1 when compared with both reference values and the TLV. Our proposed method could be used to harmonize dose-response assessment methods for the implementation of risk assessment based on the HREC according to ISHA.

Development of climate change uncertainty assessment method for projecting the water resources (기후변화에 따른 수자원 전망의 불확실성 평가기법 개발)

  • Lee, Moon-Hwan;So, Jae-Min;Bae, Deg-Hyo
    • Journal of Korea Water Resources Association
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    • v.49 no.8
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    • pp.657-671
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    • 2016
  • It is expected that water resources will be changed spatially and temporally due to the global climate change. The quantitative assessment of change in water availability and appropriate water resources management measures are needed for corresponding adaptation. However, there are large uncertainties in climate change impact assessment on water resources. For this reason, development of technology to evaluate the uncertainties quantitatively is required. The objectives of this study are to develop the climate change uncertainty assessment method and to apply it. The 5 RCMs (HadGEM3-RA, RegCM4, MM5, WRF, and RSM), 5 statistical post-processing methods (SPP) and 2 hydrological models (HYM) were applied for evaluation. The results of the uncertainty analysis showed that the RCM was the largest sources of uncertainty in Spring, Summer, Autumn (29.3~68.9%), the hydrological model was the largest source of uncertainty in Winter (46.5%). This method can be possible to analyze the changes in the total uncertainty according to the specific RCM, SPP, HYM model. And then it is expected to provide the method to reduce the total uncertainty.

Development and Implementation of the Analysis Frame for Measurement Activity in Undergraduate Physics Laboratory (대학생들의 물리실험에서 측정 활동 분석틀 개발 및 적용)

  • Shin, Kwang-Moon;Kang, Young-Chang;Lee, Sung-Muk;Lee, Jae-Bong
    • Journal of The Korean Association For Science Education
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    • v.31 no.1
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    • pp.115-127
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    • 2011
  • Analysis frame for undergraduate physics laboratory reports in collecting, processing, and analyzing data was developed. Using the frame and questionaries, we analyzed what difficulties students have in the concepts of error and uncertainty in writing laboratory reports. Students considered repetitive measurement for collecting data, but they didn't express it distinctly in their reports. They also had difficulties in measuring data around the extreme value or the large slope. Especially, most students have had difficulties with error and uncertainty. They can't apply the basic formulation to propagation of error and uncertainty. They also had the difficulties in analyzing data with concepts of error and uncertainty. While most students responded that error and uncertainty is important, there were few students who analyzed the influence of the cause of error on the results quantitatively. The result of the study showed that students have difficulties in writing the laboratory reports because they didn't have the correct concept of the error and uncertainty. So, it is needed to not only teach the physics concept about experiment but to teach basic concept of data collecting, processing, and analyzing specially about error and uncertainty for students as well.

Uncertainty Analysis of Stem Density and Biomass Expansion Factor for Pinus rigida in Korea (리기다소나무림의 줄기밀도와 바이오매스 확장계수에 대한 불확실성 평가)

  • Seo, Yeon Ok;Lee, Young Jin;Pyo, Jung Kee;Kim, Rae Hyun;Son, Yeong Mo;Lee, Kyeong Hak
    • Journal of Korean Society of Forest Science
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    • v.100 no.2
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    • pp.149-153
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    • 2011
  • This study was conducted to examine the uncertainty analysis of the stem density and biomass expansion factor for Pinus rigida in Korea. A total of 57 representative sample trees were harvested. The age class in Pinus rigida forests was divided into two, which were stands with less than 20 years and more than 21 years. The influence of stand ages on biomass expansion factor showed that it was statistically significant (p=0.0001), but it was not significant on stem density (p=0.8070). The results of this study based on the uncertainty evaluation method which were suggested by IPCC guide line indicated that stem density of the stand with less than 20 years were 30.92%, while were 25.12% the stands with more than 21years. The uncertainty in biomass expansion factor of less than 20 years and more than 21 years were 60.32% and 22.42%, respectively. The uncertainty of less than 20 years was higher compared to those stands with more than 21 years. In the case of old stand, it showed the lowest uncertainty results but younger stands showed the highest uncertainty results. This study could be applied to our country's emission factor by using stem density and biomass expansion factors which were less than 20 years and more than 21 years for Pinus rigida in Korea.

Development of a Candidate Equipment for Ozone SRP and its Uncertainty Evaluation (오존 SRP 후보 기기의 제작과 측정 불확도 평가)

  • 정규백;이진홍;우진춘
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 1999.10a
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    • pp.113-114
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    • 1999
  • 일차 오존 표준 분광기(SRP)를 제작하여 오존 측정의 정확성을 확보하고, 이것을 국가 표준으로 이용하여 현장 분석기를 차례로 교정하는 체계(그림 1 참조)를 구축하기 위하여, 먼저 자외선 흡광 광도법을 근간으로 하여 오존 SRP 후보 기기를 제작하였다.(중략)

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