• 한국초전도학회:학술대회논문집
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• v.11
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• pp.57-57
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• 2001

• Progress in Superconductivity
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• v.3 no.1
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• pp.99-103
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• 2001

We have conducted two runs of interlaboratory comparison on Ag-sheathed Bi-2223 tapes to evaluate the level of measurement techniques for the critical current measurement. Two classes of specimens were prepared for parallel and serial routings and sent to four participating laboratories. The critical currents of specimens were measured at 77 K in zero magnetic field. In the first comparison, we used twenty different Bi-2223 tapes as specimens for comparison and participating laboratories measured the specimens using their own instruments and procedures. As a result, the scattering of data on the first comparison showed -3.0% to +l2.2% for the parallel routing and -0.7% to +l5.1% for the serial routing. Major sources of these variations were attributed to different measurement techniques. Thus, the second comparison of measurement was done on the same specimens under specified measurement conditions, particularly in terms of cooling procedure and sweep rate of the test current. The variations for the second comparison were decreased -3.1% to +3.2% far the parallel routing and -1.8% to +7.7% fur the serial routing.

• Analytical Science and Technology
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• v.23 no.3
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• pp.295-303
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• 2010

In this study, the wastewater-based reference material (RM) was prepared and certified for 7 trace metal elements with evaluation of uncertainties. The RM was distributed to 25 laboratories for the interlaboratory comparison testing. The certified values and expanded uncertainties were derived using ISO guideline 35 and the standard uncertainties for homogenieties were 0.43~2.67% of certified values. The analytical results from the interlaboratory comparison testing showed normal distributions and the robust means from the interlaboratory comparison testing were higher than the certified values of the RM for all analytes.

• Journal of Korean Society on Water Environment
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• v.30 no.6
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• pp.632-637
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• 2014

Proficiency testing by interlaboratory comparisons is used to determine the performance of individual laboratories. In order to verify the quality of acute toxicity testing with Daphnia magna, National Institute of Environmental Research in South Korea is regularly organizing interlaboratory comparisons to estimate the analytical accuracy of different laboratories. Total 58 laboratories located in South Korea took part in interlaboratory proficiency testing scheme with three proficiency testing samples. TU(Toxic Unit) values of each laboratory were determined and robust z-score was calculated in order to evaluate the proficiency levels. Based on the robust z-score classification, 74% of the participant laboratories showed a satisfactory performance (43 laboratories). The main reason of 'unsatisfactory' performance seemed to be considered that the unsuitable management of test organism incubation system and the lack of experience on the identification of the test organism condition by effect of toxicity.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.10 no.6
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• pp.296-307
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• 1985

The reults of the interlaboratory measurement comparison of the multimode and single mode fiber papameters are reported. 7 multi-mode fiber spools and 4 single mode spools are used and 5 independent domestic organizations (ETRI & 4 optical fiber manufacturing companies) are participated in the comparison study. Our results are compared with those of the comparison studies conducted in the foreign countries.

• Proceedings of the Korean Nuclear Society Conference
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• 2002.05a
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• pp.419.2-419
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• 2002

• Journal of Korean Society for Atmospheric Environment
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• v.15 no.4
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• pp.485-493
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• 1999

This paper presents the results of the first interlaboratory comparison of ambient particles measurement conducted by 5 laboratories under the framework of Korean Society for Atmospheric Environment(KOSAE) on the May of 1998 in Seoul. Collection of particles less than 10$mu extrm{m}$(PM10) was carried out by two different types of PM10 sampler, and their concentration reported by three laboratories ranged from 36.2~56.05$\mu\textrm{g}$/㎥. Analyses of chemical composition of particles collected by each lab were performed by the destructive and nondestructive instrumental methods. Statistical analysis of the measurement results could not be carried out because a comprehensive QA/QC had not been applied before experiment. The importance of QA/QC as well as the performance of QA/QC for the measurement of PM10 was discussed in detail.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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• pp.43-48
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• 2005

In order to facilitate technical exchange among nations and/or institutes through the establishment of mutual recognition and the reliability guarantee of testing results by testing standards standardization, the interlaboratory comparison tests on brake discs and linings between KRRI and CARS were conducted. So far, two ways of comparison tests were performed for a better understanding of mutual recognition and standardization in railroad brake linings between Korea and China. In this paper, the first and second comparison testing results have been summarized, and the suggestions for the future research work are also presented to encourage extensive research on comparison study of railroad brake discs and linings between KRRI and CARS. Eventually, the final goal of the current research will be the establishment of standardization of railroad testing standards.

• Analytical Science and Technology
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• v.9 no.2
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• pp.145-160
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• 1996

Inorganic analytical laboratory of Korea Research Institute of Standards and Science participated in an interlaboratory comparison program operated by Quebec Toxicology Centre of Canada in 1994 and again in 1995. The objective of this program is to enable participating laboratories to assess reproducibility and accuracy of their analytical results for trace toxic elements in human biological fluids. This laboratory determined Cd and Pb concentrations in 3 levels of human blood samples by isotope dilution inductively coupled plasma mass spectrometry. 0.5mL of blood sample is added to the digestion bomb together with 2mL of nitric acid and enriched spike isotopes and then decomposed in the microwave digestion system. The decomposed sample is diluted to 10mL and nebulized into ICP-MS. The Cd and Pb values reported by all participating laboratories are presented and compared. The values reported by this laboratory are within the acceptable range of target values.

• Journal of Korean Society for Atmospheric Environment
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• v.15 no.1
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• pp.63-69
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• 1999

To offer a general guideline for the quantitative analysis of airborne pollutants, we designed and conducted a comprehensive QA/QC test using two different strategic approaches, namely (1) field-based comparative measurement and (2) laboratory-based comparative analysis. The former task was performed to make meaningful comparison of combined errors occurring from both sampling and analytical techniques in the measurements of such components as: (1) criteria pollutants, (2) volatile organic compounds (VOCs), and (3) particulate matters with the associated metals and ions. The latter task was also conducted to compare various types of bias arising mainly from the laboratory analytical procedures of (1) gaseous standards of VOCs and (2) of aqueous standards of metals and ions. The concentration data derived from each of these two different types of major tasks were evaluated per chemical species categorized as above. While the very details of these studies are to be reported on an individual basis according to the above classification of the project, this paper is presented to provide an overview of the whole project - its aim and direction.