• Korean Journal of Environmental Agriculture
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• v.30 no.2
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• pp.169-178
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• 2011

BACKGROUND: This study aimed to estimate the measurement uncertainty associated with determination of cadmium and lead from tomato paste by ICP/MS. The sources of measurement uncertainty (i.e. sample weight, final volume, standard weight, purity, molecular weight, working standard solution, calibration curve, recovery and repeatability) in associated with the analysis of cadmium and lead were evaluated. METHODS AND RESULTS: The guide to the expression of uncertainty was used for the GUM (Guide to the expression of Uncertainty in Measurement) and Draft EURACHEM/CITAC (EURACHEM: A network of organization for analytical chemistry in Europe/Co-Operation on International Traceability in Analytical Chemistry) Guide with mathematical calculation and statistical analysis. The uncertainty components were evaluated by either Type A or Type B methods and the combined standard uncertainty were calculated by statistical analysis using several factors. Expected uncertainty of cadmium and lead was $0.106{\pm}0.015$ mg/kg (k=2.09) and $0.302{\pm}0.029$ mg/kg (k=2.16), on basis of 95% confidence of Certified Reference Material (CRM) which was within certification range of $0.112{\pm}0.007$ mg/kg for cadmium (k=2.03) and $0.316{\pm}0.021$ mg/kg for lead (k=2.01), respectively. CONCLUSION(s): The most influential components in the uncertainty of heavy metals analysis were confirmed as recovery, standard calibration curve and standard solution were identified as the most influential components causing uncertainty of heavy metal analysis. Therefore, more careful consideration is required in these steps to reduce uncertainty of heavy metals analysis in tomato paste.

• Journal of Korean Society of Forest Science
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• v.99 no.6
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• pp.929-933
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• 2010

According to the IPCC guideline (2006), uncertainty assessment is very important in terms of the greenhouse gas inventory. Therefore, the purpose of this study is to estimate the basic wood density (BWD) and its uncertainty for Pinus densiflora in Korea. In this study, Pinus densiflora forests were divided into two ecotypes which were Gangwon and Jungbu regions. A total of 33 representative sampling plots was selected to collect sample trees after considering the tree ages and DBH distributions. The BWD showed statistically no difference between age classes based on IPCC's classification. While, it showed statistically difference(pvalue=0.0017) between eco-types. The BWD and uncertainty was 0.396(g/$cm^3$) and 12.9(%) for Pinus densiflora in Gangwon, while it was 0.470(g/$cm^3$) and 3.8(%) for Pinus densiflora in Jungbu. The values of the BWD uncertainty for Pinus densiflora were more precised than the values given by the IPCC guideline.

• Analytical Science and Technology
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• v.18 no.6
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• pp.475-482
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• 2005

The expression of uncertainty applied to the chemical analysis is highly recommended with increasing demands upon the systematic quality assurance and control(QA/QC) with ISO 17025. For the quantification of quality source, 7 major common sources of uncertainty, normally contributing to the quality of the chemical analysis, were selected from QA/QC literatures of chemical analysis. They were classified into repeatability, drift, uncertainty in standards, linearity of calibration, homogeneity, stability of sample, and matrix effect. And, the quantification of the sources by means of measurement uncertainty was proposed as a prerequisite steps for QA/QC. Examples applied to the quantification procedures of modelling, combination and expression of standard uncertainty for the 7 major common sources were presented as a reference guide for QA/QC in chemical analysis.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2010.04a
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• pp.263-264
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• 2010

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1629-1630
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• 2001

The high voltage measuring systems used in the testing systems shall be required to maintain the traceability to the national or international standards by the IEC 60060-2. Also all testing laboratories should prepare the documents evaluating the measurement uncertainty of the tests. By the way, this paper introduces the principal of IEC about the maintenance of traceability and evaluation methode of uncertainty.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.3
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• pp.257-262
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• 2008

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.04a
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• pp.141-142
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• 2002

대기환경 기준물질(criteria pollutants)은 NOx를 비롯하여 $O_3$, CO, SOx, PM 10, Pb 인데, 이러한 물질은 환경부에서 법적으로 규정한 대기오염공정 시험법에 따라서 분석된다. 대기오염공정 시험법이 충분한 과학적 근거를 갖는 분석법이 되기 위해서는 분석방법, 분석기기, 분석자 등에 의해 발생되는 불확실성을 최소화시키는 체계적인 관리가 필요하고, 분석기술의 발달수준, 측정분석의 요구수준, 새로운 국제 규격 통에 맞게 지속적으로 보완되어야 한다. (중략)

• Proceedings of the KIEE Conference
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• 2003.07c
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• pp.1782-1784
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• 2003

This paper evaluates the uncertainty to measurement of the power of measuring system used in the performance evaluation of electrical apparatus and introduces the reduction method of the uncertainty.

• Proceedings of the KSEEG Conference
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• 2003.04a
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• pp.39-42
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• 2003

중금속으로 오염된 폐광산 주변부나 유류누출로 인한 토양오염 등과 같은 오염부지에 대한 환경조사는 그 결과를 토대로 환경계획이나 정책이 수립되므로 의사결정의 기초가 된다. 이때, 의사결정의 타당성은 오염부지 조사결과 오염도가 얼마나 정확하게 측정되었느냐에 따라 달리 평가되어 진다. 그러므로 이와 같은 환경조사는 측정결과의 불확실성이 감소되도록 정밀한 시료채취방법이나 분석방법을 고안하여 적용해야 한다. (중략)

• Journal of the Korean Solar Energy Society
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• v.31 no.3
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• pp.89-94
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• 2011

In this study, we measured the wind data as new and renewable energy resources and carried out the evaluation of uncertainty about these data with the authentic standards. These data collected at the 20 locations in korea. We carried out the processing and evaluation about these data with standards as ISO, GUM, and IEC. Whereby these data become standards data and the credibility are gained. These data include some information as direction, humidity, pressure, temperature, and energy density. The annual average of wind speed(in Hamo) was measured as 9.5m/s, then the uncertainty was evaluated as ${\pm}0.88m/s$. We judge the credibility of data by expression of reliability quantitatively. In additional, the standards data is able to approach anywhere and it will be used to support of related research and industry.