• Journal of the Korean Vacuum Society
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• v.8 no.3B
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• pp.283-289
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• 1999

Multilayer thin film reference materials for the sputter depth profiling analysis are used to calibrate the sputter depth scale by measuring the sputtering rate and to optimize the sputtering conditions for the best depth resolution. Surface analysis group of Korea Research Institute of Standards and science (KRISS) have developed various types of multilayer thin films by using an ion beam sputter deposition and in-situ surface analysis system. The chemical states of the thin films reference materials were certified by in-situ XPS and the thicknesses were certified by transmission electron microscopy (TEM).

• The Korean Journal of Nuclear Medicine Technology
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• v.16 no.1
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• pp.108-114
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• 2012

Purpose: Immunosorbent assay most commonly used in the laboratory and commercial third-party quality control material is a substance that provided by BIO-RAD. However, in Reference Sheet by radioimmunoassay test kit or a measuring device for the mention of Acceptable Range is somewhat lacking. Radioimmunoassay for the inspection of test results by setting Acceptable Range to increase the objectivity of the recommendations on the data accumulated by the manufacturer listed in the Reference Sheet is to be issued. Materials and Methods : In our hospital since 2009 partially BIO-RAD using quality control materials in 2011, excluding certain items, some items were most of the BIO-RAD third-party quality control materials are used. Thus, internal quality control data accumulated BIO-RAD's Unity Real Time program by using the items were measured. Results : BIO-RAD using quality control material items were about 50 of the 20 Point Data averages, standard deviations, variation coefficients were calculated to measure the Acceptable Range of kit, automated immunoassay attributed Roche Elecsys / E170 / cobas e Systems the measures and compared. Conclusions : BIO-RAD QC materials commonly used hospital and peer group by setting the measurement kit, suitable for laboratory equipment for radioimmunoassay of Acceptable Range manufacturer recommendation to increase the objectivity of the test results by national and international recognition for radioimmunoassay should seek to increase.

• Bulletin of the Korean Chemical Society
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• v.31 no.5
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• pp.1149-1154
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• 2010

Liquid chromatography/mass spectrometry using isotope dilution method has been established as a primary method for the measurement of cortisol in human serum. Verification of this method was accomplished by the participation in Consultative Committee for Amount of Substance-Metrology in Chemistry (CCQM) pilot study. Two levels of cortisol certified reference materials were prepared and certified by the established method. They were used as sample materials for the proficiency testing. The expanded uncertainty in the measurement of cortisol in human serum was approximately 1.2% at 95% confidence level. The results of the proficiency testing showed a good precision among the participants, but some bias to the certified values. This means that commercial field laboratories should keep traceability chain to SI unit through available reference measurement procedures and/or available reference materials.

• Korean Journal of Mineralogy and Petrology
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• v.33 no.1
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• pp.65-71
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• 2020

Glass reference materials have been essentially used for precise geochemistry analytical techniques. In order to make up for the drawback of synthetic glass reference materials, which have the high uncertainty caused by the difference in composition of natural rocks, we introduce a glass geostandard using natural glass. The NK-B1G sample, which comes from the Baekdusan obsidian, is a natural glassy rock that contains only few crystals such as microlites or inclusions. We examined the feasibility of the sample as a reference material for microanalysis like EPMA or LA-ICPMS.

• Korean Journal of Materials Research
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• v.13 no.10
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• pp.651-657
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• 2003

Ultrasonic microscope has been used to detect the defects on surface or inner solid. Conventionally, it has used at a single operating frequency. The resolution and quality of the measured images are determined by a characteristic of the transducer of the ultrasonic microscope. The conventional ultrasonic microscope has been used envelope detector to detect the amplitude of reflected signal, but the changes in amplitude is not sensitive enough for specimen with microstructure that in phase. In this paper, we have studied multi-frequency depth resolution enhancement with ultrasonic reflection microscope for the reflectors of a stainless steel reference specimen and a reference calibration block to be used as the material in nuclear power plants for ISI, PSI. Increased depth resolution can be obtained by taking two, three-dimensional images at more that one frequency and numerically combining the results. As results of the experiment, we could get enhanced images with the rate of contrast in proportion and high quality signal distribution for the image to the changing rate of depth for the reflectors of the two kinds of specimens.

• The Journal of the Acoustical Society of Korea
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• v.29 no.1E
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• pp.38-44
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• 2010

This paper is based on our comments and proposed amendments to the documents, Annex A, Phantom for determining Maximum Depth of Penetration, and Annex B, Local Dynamic Range Using Acoustical Test Objects 87/400/CDV. IEC 61391-2 Ed. 1.0 200X, prepared by IEC technical Committee 87; Ultrasonics. The documents are concerned with the influence of microstructure of reference target material on the ultrasonic backscattering. Previous works on the attenuation due to backreflection and backscattering of reference target materials are reviewed. The drawback to the use of ungraded stainless steel and metallic materials without microstructural data such as, crystal structure, basic acoustic data of sound velocity and attenuation, grain size, roughness and elastic constants has been discussed. The analysis suggested that the insightful conclusion can be made by differentiating the influence arising from target size and microstructure on the backscattering measurements. The microstructural parameters are associated with physical, geometrical, acoustical and mechanical origins of variation with frequency. Further clarification of such a diverse source mechanisms for ultrasonic backscattering would make the target material and its application for medical diagnosis and therapy simpler and more reliable.

• Mass Spectrometry Letters
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• v.14 no.4
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• pp.166-172
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• 2023

The utilization of methyl 2-aminobenzoate as a biocide and pesticide has raised concerns regarding its potential toxicity. To assess its safety, it is crucial to determine its quantity and related toxicity using reference materials (RMs) or certified reference materials (CRMs). As an RM and CRM containing methyl 2-aminobenzoate within a biocidal product matrix is currently unavailable, this study aimed to produce a high-quality RM containing methyl 2-aminobenzoate, ensuring its homogeneity and stability, following the ISO Guide 35 and ISO 17034. The study determined that the produced RM exhibited homogeneity, as indicated by a calculated F-value (1.91) smaller than the critical F-value (3.02). In the assessment of isochronous short-term stability, the slope of the linear regression for the RM showed no statistically significant difference from zero when stored at temperatures of 4, 18, and 60 ℃ for 4 weeks. Regarding classical long-term stability, the RM demonstrated sustained stability over the course of one year when stored at 4 ℃. This study has successfully developed an RM for monitoring methyl 2-aminobenzoate in biocides and pesticides. Its quality underwent rigorous evaluation, confirming both homogeneity and stability.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.2 no.1
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• pp.66-87
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• 1974

It is the prime importance of the information and the reference-librarians to better understand the communication functions of the library since they are the ones to whom the library users come first with their informational needs. Reference librarians often have the problem of providing information to those who may have little experience with, or interest in the library. There is also a problem of finding out what the person really wants, not what he says he wants. Therefore, the interaction between the librarian and the user involves a highly complex activity of communication with each other even before the actual search begins. Reference librarians cannot perform to any degree of success without comprehension of the general patterns and processes of communication in information seeking. Nonverbal as well as verbal transmittal process on the part of both librarians and patrons should not be overlooked. Some of the difficulties and barriers of library communication are brought so that possible cures and improvement may be sought. The basic purpose of the reference interview through which this interpersonal communication takes place is for the reference specialist to enable to link the needs of the patron with potential resource of the library. The writer firmly believes that this importance of the process be taught as well as the materials in reference service regardless of the level of the course offered in library science department.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.8 s.251
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• pp.873-879
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• 2006

To investigate applicability of the reference stress approach as simplified inelastic stress analysis to estimate local creep rupture, detailed finite element stress analyses of a T-piece pipe with different inner pressure and system loading levels are performed. The reference stresses are obtained from the finite element (FE) limit analysis based on elastic-perfectly-plastic materials, from which the local reference stress for creep rupture is determined from R5. The resulting inelastic stresses are compared with elastic stresses resulting from linear elastic FE calculations. Furthermore they are also compared with the stresses from full elastic-creep FE analyses. It shows that the stresses estimated from the reference stress approach compare well with those from full elastic-creep FE analysis, which are significantly lower than the elastic stress results. Considering time and efforts for full inelastic creep analysis of structures, the reference stress approach is shown to be a powerful tool for creep rupture estimates and also to reduce conservatism of elastic stress analysis significantly.

• Journal of Soil and Groundwater Environment
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• v.19 no.6
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• pp.49-58
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• 2014

This study was implemented as a part of the experiment to develop two kinds of soil-based Benzo[a]pyrene (BaP) proficiency testing materials (PTMs) for soil analysis. A test was carried out for the check of solubility of the reference material (high purity reagent) using several solvents. Another test was also conducted for the evaluation of homogeneity and stability of two kinds of candidate soil reference materials. The test analysis of BaP in terms of the candidate materials was conducted according to the Standard Soil Analytical Methods by Ministry of Environment. Dissolution of the reference material was shown to vary depending on solvent type and was higher in the order of Dichloromethane > Acetone > Acetone/MeOH (9 : 1) > N-hexane. In addition, the slope on calibration curve for BaP standard solutions was largest on BaP standard solutions prepared with dichloromethane of the tested solvents. Such tendency appeared egually in the commercial BaP standard solution. Therefore, it is thought to be reasonable to use dichloromethane as the solvent in case of the standard stock solution that is used for the measurement of BaP concentration in soil. ISO 13528 and IUPAC protocol were used for verification of homogeneity on the two kinds of soil candidate materials, Both candidate materials were sufficiently homogeneous. Stability assessment of the two candidate materials was made according to ISO Guide 35 and the result showed that both batches did not have any long-term and short term stability issues that might occur during shipping. However, monitoring results of BaP concentration in soil showed that BaP concentration of the two batches measured at 15 days after the sample preparation was reduced by about 24~37% compared with that of the samples measured on 0 day of the sample preparation. Identification was done with several treatments such as irradiation and sterilization etc. The major cause was shown to be irradiation to the samples.