• Nuclear Engineering and Technology
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• v.55 no.8
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• pp.2797-2801
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• 2023

CdZnTeSe (CZTS) has attracted attention for applications in X- and gamma-ray detectors owing to its improved properties compared to those of CdZnTe (CZT). In this study, we grew and processed single crystals of CZT and CZTS using the Bridgeman method to confirm the feasibility of using a dosimeter for high-energy X-rays in radiotherapy. We evaluated their linearity and precision using the coefficient of determination (R²) and relative standard deviation (RSD). CZTS showed sufficient RSD values lower than 1.5% of the standard for X-ray dosimetry, whereas CZT's RSD values increased dramatically under some conditions. CZTS exhibited an R² value of 0.9968 at 500 V/cm, whereas CZT has an R² value of 0.9373 under the same conditions. The X-ray response of CZTS maintains its pulse shape at various dose rates, and its properties are improved by adding selenium to the CdTe matrix to lower the defect density and sub-grain boundaries. Thus, we validated that CZTS shows a better response than CZT to high-energy X-rays used for radiotherapy. Further, the applicability of an onboard imager, a high-energy X-ray (>6 MV) image, is presented. The proposed methodology and results can guide future advances in X-ray dose detection.

• Natural Product Sciences
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• v.16 no.3
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• pp.180-184
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• 2010

The simple and accurate method was established for the simultaneous determination of (-)-menthone and (-)-menthol in Menthae herba obtained from Korea and China. A quantitative analysis was performed with a gas chromatography-flame ionization detector and reference compounds were separated on a capillary HP-Innowax column (30 m $\times$ 0.23 mm, 0.50 ${\mu}m$, Agilent, MA, USA). The correlation coefficients of the compounds showed good linearity ($r^2$ > 0.9997) over the linear range. The precision, repeatability and stability showed less than 1.7% of relative standard deviation (RSD) values for two compounds. Recovery rates were within the range of 95.72 - 103.76%. The method was applied successfully to analyze 15 samples of Menthae herba and achieved sufficient and specific separation of reference compounds. The principal component analysis (PCA) exhibited the classification of 15 samples according to their locations of origin.

• Analytical Science and Technology
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• v.19 no.6
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• pp.490-497
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• 2006

The sources of uncertainty in the analysis of liquified natural gas (LNG) process are evaluated. The uncertainty sources evaluated are the repeatability of measurement, non-linearity of GC, the uncertainty of standard gas used for calibration, difference of gas sampling and deviation after GC calibration and major revealed sources are the non-linearity of GC, the uncertainty of standard gas and the deviation after GC calibration. The determined values and uncertainties of methane and ethane as the major components are $90.0%mol/mol{\pm}1.9%$ (relative and 95% level of confidence) and $6.26%mol/mol{\pm}0.08$ (relative and 95% level of confidence), respectively. The contribution of uncertainty varies depending on the source of uncertainty and gas component. In the case of methane, non-linearity of GC, the uncertainty of standard gas and deviation after GC calibration contribute 0.28%, 0.25% and 0.24% of relative expanded uncertainty, respectively.

• Journal of Biosystems Engineering
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• v.31 no.5 s.118
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• pp.443-448
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• 2006

For development of an on-line monitoring unit of fermentation process, an auto dilution unit based on traditional chemical and biological analytical method was developed and the performance was evaluated. The dilution unit was constructed with two syringe pumps and flow direction change valves and fully automated. Total delivery volume of two pumps using distilled water was measured to confirm the operating stability And diluted concentrations of three substrate solutions (glucose, lactic acid, ethanol) were compared with a standard method with a high performance liquid chromatograph (glucose, lactic acid) and gas chromatograph (ethanol). Relative error values of total delivery volume of the pumps were below 3% and standard deviation values were 0.003 (n=5). Relative error values of diluted concentration of the dilution unit measurements were below 2% with 1/10 of dilution ratio and 70, $80{\mu}{\ell}$ of sample volume conditions for glucose and lactic acid, 1/30 of dilution ratio and $70{\mu}{\ell}$ of sample volume conditions for ethanol, respectively. In case of the ethanol, cause of the evaporative characteristics, the relative error values showed over 5% whole experimental conditions.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.37 no.5
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• pp.323-330
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• 2019

Radiometric normalization with multi-temporal satellite images is essential for time series analysis and change detection. Generally, relative radiometric normalization, which is an image-based method, is performed, and histogram matching is a representative method for normalizing the non-linear properties. However, since it utilizes global statistical information only, local information is not considered at all. Thus, this paper proposes a histogram matching method considering local information. The proposed method divides histograms based on density, mean, and standard deviation of image intensities, and performs histogram matching locally on the sub-histogram. The matched histogram is then further partitioned and this process is performed again, iteratively, controlled with the wasserstein distance. Finally, the proposed method is compared to global histogram matching. The experimental results show that the proposed method is visually and quantitatively superior to the conventional method, which indicates the applicability of the proposed method to the radiometric normalization of multi-temporal images with non-linear properties.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.09a
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• pp.148-150
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• 2001

Solid-phase microextraction (SPME) was investigated to understand the BTEX extraction behavior of SPME in groundwater. Analytical procedure was conducted In both conventional and headspace mode. And the conventional direct extraction method and the headspace analysis method were compared. Data obtained with direct and headspace SPME were very similar and showed successful results. In headspace analysis, the linearity was better and RSD (relative standard deviation, %) was smaller than direct extraction.

• Journal of The Korean Astronomical Society
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• v.29 no.spc1
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• pp.313-314
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• 1996

Assuming that the solar activity and the solar cycle phenomena may be manifestations of global torsional MHD oscillations, we compute the Alfven wave travel times along the field lines in the five models of magnetic field described in the following text. For all these models, we compute standard deviation and it's ratio to mean Alfvenic wave travel times. The last two models yield the smallest relative bandwidth for the frequencies of the MHD oscillations. However, the last model is the only admissible one which can sustain global Alfvenic oscillations with well defined frequency for the fundamental mode

• Food Science and Biotechnology
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• v.18 no.5
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• pp.1118-1123
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• 2009

Event-specific real-time polymerase chain reaction (PCR) detection method for genetically modified (GM) maize MIR604 was developed based on integration junction sequences between the host plant genome and the integrated transgene. In this study, 2 primer pairs and probes were designed for specific amplification of 100 and 111 bp DNA fragments from the zSSIIb gene (the maize endogenous reference gene) and MIR604. The quantitative method was validated using 3 certified reference materials (CRMs) with levels of 0.1, 1, and 10% MIR604. The method was also assayed with 14 different plants and other GM maize. No amplification signal was observed in real-time PCR assays with any of the species tested other than MIR604 maize. As a result, the bias from the true value and the relative deviation for MIR604 was within the range from 0 to 9%. Precision, expressed as relative standard deviation (RSD), varied from 2.7 to 10% for MIR604. Limits of detections (LODs) of qualitative and quantitative methods were all 0.1%. These results indicated that the event-specific quantitative PCR detection system for MIR604 is accurate and useful.

• YAKHAK HOEJI
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• v.28 no.1
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• pp.21-23
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• 1984

High performance amino acid analyzing method has been developed for the routine analysis of taurine in preparations. Ion-exchange resin #2619 Hitachi Custom Ion-Exchange Resin, $2.6(I.D.){\times}150$(length)mm was used as column, buffer I, pH 3.3 as mobile phase. The retention time of taurine was 7 minutes. Calibration curve by peak height for standard taurine was linear from 2.5ppm to 25ppm. The reproducibility showed relative standard deviation $\pm$1.9% when analyzed 10 times for standard solution. The samples could be continuously analyzed without regenerating the resin between samples. Five samples were applied to column every 12 min. and then the resin was regenerated for 30 min. during one analyzing cycle time, 90 min. The automatic amino acid analyzer has made it possible to assay multiple samples in a relatively short period of time using the analytical magnetic program card. The high sensitivity and specificity of the analytical column of the automatic amino acid analyzer permits the routine analysis of taurine in preparations.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.23 no.4
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• pp.251-258
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• 2011

The objective of this study is to propose two empirical correlations to predict the mass flow rate through an automotive block type thermostatic expansion valve and then to evaluate the correlations. The first correlation is deduced by modifying the basic equation of the orifice meter for the mass flow rate and the second correlation is deduced by using the Buckingham's ${\pi}$ theorem. The first correlation showed very good agreement on the measured data for R134a, given by Monforte. Average relative deviation and standard deviation of it are 2.5% and 1.6%, respectively. The second correlation agreed on the same measured data with a little greater deviations. The two correlations may apply to common expansion valves which have different geometrical sizes of the same shape.