• Analytical Science and Technology
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• v.30 no.5
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• pp.287-294
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• 2017

As the demand for natural gas increases with industrial development, the supply of natural gas is expected to become unstable with a shortage of imported natural gas. It is hence necessary to meet this demand by introducing and developing various types of natural gas, such as pipeline natural gas (PNG) and substituted natural gas (SNG), in addition to liquefied natural gas (LNG). The components included in PNG as well as their concentrations must be measured accurately, and a standard gas should be developed to accurately measure hydrocarbons ($C_6-C_{10}$), which are trace components included in natural gas. The components in the primary standard gas mixtures (PSMs) developed in the present study were hexane, heptane, octane, nonane, and decane with concentrations of $10-30{\mu}mol/mol$ with methane as the balance gas. Standard hydrocarbon ($C_6-C_{10}$) gas mixtures were prepared in aluminum cylinders by a gravimetric method with traceability following ISO 6142 with raw material gases, for which the purity of each component was analyzed completely. The prepared standard gas mixtures were analyzed by to evaluate the preparation consistency between the standard gas mixtures, the adsorbability of the cylinders, the variation of the stability, and the uncertainty. The results showed that aluminum cylinders have little adsorptive loss on their internal surfaces with excellent long-term stability. The developed standard gas mixture, containing hexane, heptane, octane, nonane, and decane with concentrations of $10-30{\mu}mol/mol$, showed an uncertainty in a range of 0.79 % - 1.63 %.

• Analytical Science and Technology
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• v.37 no.3
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• pp.166-173
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• 2024

Steroids have a temporary skin improvement and whitening effect by controlling vasodilation, but they also cause side effects when used for a long time. Therefore, steroids were designated and managed as raw materials that cannot be used in cosmetics in Korea. However, steroids are continuously being detected in cosmetics, causing social issues. In this study, we developed a certified reference material (CRM) for the determination of steroids such as hydrocortisone in cosmetics. A cream-type cosmetic CRM was manufactured and subsequently certified following the guidelines outlined in ISO Guide 35. Homogeneity, short-term stability, and long-term stability were evaluated using isotope dilution mass spectrometry (ID-MS). The certified values were determined by using NIST's primary reference material to ensure traceability. From now on, we intend to supply the certified reference material as a cosmetic CRM to national and international companies, as well as research institutes after certification as certified reference material from KOLAS and registering on COMAR.

• Management & Information Systems Review
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• v.38 no.4
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• pp.61-78
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• 2019

When calculating gains from transfers of assets inherited or donated, the value recognized at the market price as of the date of inheritance or acquisition is recognized as the actual transaction value at the time of acquisition. However, Precedents for the appeal for review by the NTS, the request for adjudgment by the Tax Tribunal(TT) and the request of examination by the Board of Audit and Inspection of Korea(BAI) and the cases of the lawsuit have not shown a consistent results on how much such a the actual transaction value will be measured. This study investigates the operating state of the current tax appeal system using the statistical data of the TT, NTS, and BAI and cases of the lawsuit from 2008 to 2017, and suggests the Improvement of Capital Gains Tax Act on the transfer of inherited and donated property. As a result, total number of requested cases has diminished because cases of the pre-assessment review and the reconsideration appeal by the NTS have decreased steadily over the past decade, while the cases of the lawsuit and the administrative trials(the request for adjudgment by the TT, the appeal for review by the NTS, and the request of examination by the BAI) have been steadily increasing. Also This study found that more than 40% of the complainants proceeded with the cases of the lawsuit proceedings in disagreement with the disposition of tax dissatisfaction under the administrative trials. In addition, Even though the retrospective appraisal price is not recognized as the market price due to the strict interpretation of the tax regulations, it can be seen that it is interpreted as a more expanded concept in the application of the market price than the government office or the tax judge. Therefore, according to the precedents of the cases lawsuit, it is necessary to establish a regulation on the recognition of retroactive appraisal value.

• Analytical Science and Technology
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• v.18 no.4
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• pp.271-277
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• 2005

Urea in blood has been measured as an effective marker for diagnosis of renal function. Urea which is e end-product of nitrogen containing metabolites such as proteins is filtered through glomeruli of kidneys and then excreted as urine. If the renal function is deteriorated, the urea concentration in blood will be increased, from which the healthiness of renal function is judged. In order to improve the confidence of diagnosis results, the results must keep traceability chain to certified reference materials, which was certified by primary reference method. In this study, we proposed isotope dilution-liquid chromatography/mass spectrometry (ID-LC/MS) as a candidate primary method, in which $15^N_2$-urea is used as an internal reference material. The developed method is highly accurate in principle and is convenient as it does not require cumbersome derivatization. 0.1 mmol/L ammonium chloride was selected as a mobile phase for HPLC because it provided low interference in MS analysis of relatively low molecular weighted urea. HPLC and MS were connected with an electrospray ionization (ESI) interface of positive mode, which provided high sensitivity and reproducibility. The developed method was validated with internationally recognized reference materials, and we have obtained satisfactory results in an international ring trial. The expanded uncertainty calculated according to ISO guide was 1.8% at 95% confidence interval. The developed method is being used as a primary reference measurement method such as for certification of serum certified reference materials (CRMs).

• Analytical Science and Technology
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• v.25 no.5
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• pp.273-283
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• 2012

Phthalate plasticizers are regulated by RoHS, REACH and CPSC as hazardous substances. Responding to these international environmental restrictions, we developed ABS certified reference material (CRM) for determination of phthalate plasticizers such as DMP, DEP, DBP, BBP, DEHP and DnOP. The candidate material has been made with ABS resin widely used in electric and electronic products and 6 kinds of phthalate plasticizers. The making of the material involved a series of processes like extruding, cooling, pelletizing, and drying using twin screw extruder. Then it has been certified according to ISO Guide 35. Using isotope dilution-gas chromatography/mass spectrometry (ID-GC/MS), homogeneity, short-term stability, and long-term stability were evaluated. The certified values were determined by using primary reference material (PRM) of KRISS for traceability. From now on, we will provide ABS CRM to national and international companies and research institutes after certification as certified reference material and registering on COMAR (code of reference material).

• Proceedings of the KIEE Conference
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• 2004.07c
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• pp.1969-1971
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• 2004

For evaluation of partial discharge performances of electrical power appratus such as Insulator, circuit breaker and transformer and so on, Partial discharge measuring system(ERA) consisted of PD detector including amplifier, coupling capacitor, PD calibrator and voltage divider are used PD measuring system is very important factor which affect the test result and show reliability of test result in test laboratory, In this paper, we describe tracebility and uncertainty of PD measuring system in test laboratory based on IEC 60270.

• Proceedings of the KIEE Conference
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• 2003.07c
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• pp.1632-1634
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• 2003

For lihgtning and switching impulse voltage performances in laboratories, impulse voltage measuring system, which is consisted of voltage divider, recording instrument and connecting system between divider and recording instrument, is used. In order to show reliability of test result in test laboratory, tracebility of these measuring system to be using in test laboratory is needed. In this paper, we describe tracebility and uncertainty of impulse voltage measuring system in test laboratory.

• Analytical Science and Technology
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• v.24 no.1
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• pp.1-9
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• 2011

We described an estimation of measurement uncertainty in quantitative analysis of 11-nor-9-carboxy-${\Delta}^9$-tetrahydrocannabinol (THC-COOH), the metabolite of ${\Delta}^9$-tetrahydrocannabinol, in hair samples by using the bead-assisted liquid-liquid extraction and gas chromatography-tandem mass spectrometric (GC-NCI-MS/MS) detection. Traceability of measurement was established through the use of reference materials, calibrated volumetric tubes, volume measuring devices, and measuring instruments. The analytical results were compared and the different contributions to the uncertainty were evaluated. Inter-day variation was performed by using statistical analysis of several indicative factors. Measurement uncertainty associated with the analyte in real forensic hair samples were estimated using QC data. The major factor of contribution to combined standard uncertainty was inter-day repeatability, while those associated with preparation of analytical standard and also sample of weight were insignificant considering the degree of contribution. Relative uncertainty of relative extended standard uncertainty divided into the measured concentration of the analyte was 17% in a hair sample. The uncertainty of result evaluation will be invaluable to improve quality of the analysis.

• The Journal of the Korea Contents Association
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• v.13 no.1
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• pp.175-185
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• 2013

The judgement which is subject of research has denied legal rescission of division of the inherited property by agreement based on (1) the fact that the division of inherited property terminated at the time of concluding mutual agreement in its nature while only the relationship of claim and obligation between the inheritor who has paid for such obligation and the inheritor who has acquired such obligation in the mutual agreement remains (2) and the fact that the legal stability is considerably hindered as the re-partition of inherited property having retroactive effect becomes unavoidable in case of approving the legal rescission of the division of the inherited property by agreement. But it is reasonable to also approve legal rescission on the division of the inherited property by agreement in case the division by agreement actually has the nature such as conditional donation between joint heirs (1) from the fact that the division of the inherited property by agreement gets the nature of disposal equivalent to exchange, transfer and abandonment of share between joint heirs in actuality, (2) and the fact that there are no other theories in approving the validity of mutually agreed rescission despite the fact that the re-partition of inherited property having retroactive effect is unavoidable even in case of the mutually agreed rescission of the division by agreement among all joint heirs. However, as the division of the inherited property by agreement is a contract that gets concluded only if all joint heirs participate, even the legal rescission for the reason of not fulfilling the obligations paid by one party of the heirs during the division by agreement must be considered as possible only by expression of intentions from all other joint heirs excluding this one party.

• The Korean Journal of Nuclear Medicine Technology
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• v.18 no.1
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• pp.158-162
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• 2014

Purpose: Reference material (RM) is defined as material that is safe and homogeneous enough about specified characteristic that is made with a purpose of using test of measurement or nominal characteristic. Certified reference material (CRM), which is issued by authorized organization, is defined as reference material that provides characteristic value, link uncertainty and retroactivity. The purpose of this paper was to evaluate recovery of radioimmunoassay by Certified Reference Material enclosed with a certificate and therefore to enhance reliability of test. Materials and Methods: WHO certified reference material is purchased from NIBSC (National Institute for Biological Standard and Control, United Kingdom) and made of 3 levels that are C-1 (low concentration), C-2 (medium concentration) and C-3 (high concentration) and measured for kit at the Seoul National University Hospital. Recovery rate is evaluated after measurement at four different days. Results: Recovery rate results using WHO certified reference material are T4 90%, Ferritin 88%, PSA 94%, Prolactin 99%, AFP 94% and TSH 93%. Conclusion: A procedure that appropriate accuracy, precision, specificity, sensitivity, reproducibility, and validate on the subject of kit for radioimmunoassay is essential. Recovery rate assay as extraction efficiency of analysis process is percent about already measuring results of analysis result after all measuring process. This is very important assessment standards of performance evaluation of immunoassay kit. Recovery rate results of 6 type used WHO CRM are satisfactory to 88~99%. This demonstrates that the radioimmunoassay is a very accurate measurement, which is very effectively utilized in clinical practice.