• Journal of Pharmaceutical Investigation
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• 제35권6호
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• pp.431-436
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• 2005

A high-performance liquid chromatographic method was validated for quantitation of nadolol in human plasma. Nadolol and internal standard, pindolol, were extracted with tert-butyl methyl ether after addition of 10 M sodium hydroxide solution. The analytes were separated on a reverse phased C18 column using a mobile phase consisting of 0.05 M ammonium phosphate monobasic buffer, acetonitrile and methanol (81: 17:2 v/v/v) and detected using a fluorescence detector (excitation wavelength 230 nm, emission wavelength 294 nm). The method was specific and sensitive enough to detect as low as 3 ng/mL of nadolol in human plasma. Linear calibration range was 3-150 ng/mL with correlation coefficient greater than 0.999. The overall accuracy was in the range of 96.8 to 103% and precision C.V.(%) 7.30 to 12.2%. The recovery was approximately 100% and stability was confirmed during storage and sample preparation. The present HPLC method was successfully applied to study bioavailability after oral administration of 80 mg of nadolol in healthy Korean subjects. The mean $AUC_{t}$ was $1968{\pm}397\;ng{\cdot}hr/mL$ and $C_{max}$ of $186{\pm}79.3\;ng/mL$ was reached at $3.5{\pm}0.76\;hr$. The mean $t_{1/2}$ of nadolol was $17.3{\pm}2.59\;hr$.

• Bulletin of the Korean Chemical Society
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• 제33권11호
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• pp.3727-3734
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• 2012

An analytical method has been developed for the rapid determination of perfluorinated compounds (PFCs) in human serum samples. The extraction and purification of PFCs from human serum were performed by the modified method of previous report. Ten PFCs were rapidly separated within 3.3 min by C18-monolithic column liquid chromatography (LC) and detected by electrospray ionization (ESI) tandem mass spectrometry (MS/MS) in negative ion mode. The runtime of PFCs on monolithic column LC was up to 4-fold faster than that on conventional column LC. The effect of triethylamine (TEA) to the mobile phase has investigated on the overall MS detection sensitivity of PFCs in ESI ionization. Quantification was performed by LC-MS/MS in multiple-ion reaction monitoring (MRM) mode, using $^{13}C$-labeled internal standards. Method validation was performed to determine recovery, linearity, precision, and limits of quantification, followed by, the analysis of a standard reference material (SRM 1957 from NIST). The overall recoveries ranged between 81.5 and 106.3% with RSDs of 3.4 to 16.2% for the entire procedure. The calibration range extended from 0.33 to 50 $ng\;mL^{-1}$, with a correlation coefficient ($R^2$) greater than 0.995 and the limits of quantification with 0.08 to 0.46 $ng\;mL^{-1}$. This approach can be used for rapid and sensitive quantitative analysis of 10 PFCs in human serum with high performance and accuracy.

• Journal of Microbiology and Biotechnology
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• 제16권2호
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• pp.205-211
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• 2006

A quantitative analytical method to detect new lines of genetically modified (GM) maize, NK603 and TC1507, has been developed by using a real-time polymerase chain reaction (PCR). To detect these GM lines, two specific primer pairs and probes were designed. A plasmid as a reference molecule was constructed from an endogenous DNA sequence of maize, a universal sequence of a cauliflower mosaic virus (CaMV) 35S promoter used in most GMOs, and each DNA sequence specific to the NK603 and TC1507 lines. For the validation of this method, the test samples of 0, 0.1, 0.5, 1.0, 3.0, 5.0, and 10.0% each of the NK603 and TC1507 GM maize were quantitated. At the 3.0% level, the biases (mean vs. true value) for the NK603 and TC1507 lines were 3.3% and 15.7%, respectively, and their relative standard deviations were 7.2% and 5.5%, respectively. These results indicate that the PCR method developed in this study can be used to quantitatively detect the NK603 and TC1507 lines of GM maize.

• Journal of Electrical Engineering and Technology
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• 제12권5호
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• pp.1945-1954
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• 2017

In recent years, several LCL filter design methods for different converter topologies have been published, many of which use analytical expressions to calculate the ideal converter AC voltage harmonic spectrum. This paper presents the LCL filter design methodology but the focus is on presentation and validation of the non-iterative filter design method for a grid-connected three-phase two-level PWM-VSC. The developed method can be adapted for different converter topologies and PWM algorithms. Furthermore, as a starting point for the design procedure, only the range of PWM carrier frequencies is required instead of an exact value. System nonlinearities, usually omitted from analysis have a significant influence on VSC AC voltage harmonic spectrum. In order to achieve better accuracy of the proposed procedure, the system nonlinear model is incorporated into the method. Optimal filter parameters are determined using the novel cost function based on higher frequency losses of the filter. An example of LCL filter design for a 40 kVA grid-connected PWM-VSC has been presented. Obtained results have been used to construct the corresponding laboratory setup and measurements have been performed to verify the proposed method.

• 한국수자원학회논문집
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• 제39권10호
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• pp.867-880
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• 2006

많은 수의 매개변수와 복잡한 구조를 가진 수문모형의 적용 시 세밀하고 강력한 모델 검 보정이 요구된다. 본 연구에서 금강유역에 위치한 갑천 소유역에 준 분포형 모형인 SWAT모형을 이용하여 다 목적 지점 검 보정 방법을 제시하였다. 모형의 보정 전 민감도 분석을 통한 각 소유역별로 특성 분석이 이루어 졌고, 유출에 민감한 매개변수들을 추정하였다. 그리고 최소한의 보정을 통한 모형의 유효성을 높이기 위해, 관측된 데이터로부터 매개변수 값을 선보정하는 과정을 거쳤다. 그 결과 각 소유역 별로 다른 매개변수들의 민감도가 나타났다. 관측유량에 대한 보정 단계에서 $R_{eff}$는 0.41-0.84, $R^2$은 0.5-0.86 값으로 신뢰성 있는 결과를 얻었다. Recursive digital filter로 추정된 기저 유출량을 약 2% 범위에서 산정하였다. 관측 지하수 수위와의 비교에서도 전체적으로 관측된 지하수 수위의 시간적 변동추이와 변동 폭을 잘 나타내었으며, $R^2$는 0.69로 만족스러운 결과를 보였다. 결론적으로, 다 목적 지점 방법의 사용은 모형기 구조와 추정된 매개변수들에 높은 신뢰도를 제공하였다.

• 한국식품영양과학회지
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• 제43권11호
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• pp.1791-1795
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• 2014

본 연구에서는 HPLC를 사용하여 채소류 식품군에서 비타민 K1의 분석법을 확립하고 이에 대한 분석법 검증하고자 하였다. 그 결과 본 시험법에서 표준용액의 피크유지시간과 부추 추출액의 피크유지시간이 일치하여 특이성을 확인하였다. 검량선의 상관계수($R^2$)는 0.9994 이상으로 높은 유의수준을 보여 분석에 적합함을 알 수 있었으며, 검출한계는 0.1335 ng/injection volume($50{\mu}L$)이었고 정량한계는 0.2784 ng/injection volume($50{\mu}L$)으로 설정되었다. 일내, 일간분석에서 정밀도를 나타내는 변동계수(coefficient variation, CV)는 표준용액에서 각각 1.979%, 2.107%로 나타내었고 정확성은 99.439%로 나타내어 채소류에서 비타민 K1의 분석법이 적합한 시험법임이 검증되었다. 본 분석법에 따라 채소류의 비타민 K1을 분석한 결과 식품공전의 효소를 이용한 분석법보다 더 높은 추출률을 나타내었으며 다른 물질의 간섭 없이 분석 가능하여 채소류의 비타민 K1의 검출에 응용되어 이용될 수 있을 것으로 판단된다.

• 한국식품위생안전성학회지
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• 제36권5호
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• pp.376-381
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• 2021

Red beet roots (Beta vulgaris L.)는 천연색소로 붉은 색계열의 betacyanins은 75-95%의 betanine와 이성질체인 isobetanine 15-45%으로 존재한다. 본 연구는 비트레드를 사용한 식품에 대해 HPLC-DAD를 이용하여 지표성분인 betanine 및 isobetanine에 대해 분석법을 확립하였으며, 유효성 검증을 위해 직선성, 검출한계, 정량한계, 정확성, 정밀성, 측정불확도를 측정하였다. 캔디류, 빙과류, 코코아 가공품의 matrix에 적용하여 matrix matched calibration법을 사용하였으며 R²이 0.9998 이상으로 높은 직선성을 보였다. 검출한계와 정량한계는 각각 0.16-0.32 mg/L, 0.48-0.97 mg/L으로 확인되었다. 분석법의 정확성 및 정밀성을 검증하기 위해 intra-day 및 inter-day 반복 실험 결과, 회수율은 96.0-103.1 %, 100.0-102.2 %이였으며, RSD는 0.5-3.3 %, 0.9-3.8 %로 산출되었다. 측정불확도는 매트릭스 및 측정 농도에 따라 1.71-12.43%로 평가되었다. 또한, 확립된 분석법의 적용성 검토를 위해서 비트레드 색소를 사용한 가공식품 26종을 분석한 결과, betanine과 isobetanine을 정량 할 수 있었다 (8.4-3,823.4 mg/kg).

• 약학회지
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• 제52권1호
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• pp.7-11
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• 2008

A high performance liquid chromatographic (HPLC) method for the determination of glycyrrhizic acid was developed for the quality control of traditional herbal medicinal preparation Bu-Zhong-Yi-Qi-Tang (BZYQT), which is well-known herbal medicine used as tonic. RP-HPLC analysis was carried out using Capcell pak $C_{18}$ MG column $(5\;{\mu},\;150{\times}4.6\;mm)$ and a mobile phase consisting of acetonitrile and water containing 0.03% phosphoric acid (pH 2.46) at a flow rate of 1.0 ml/min. The optimum wavelength for the detection of the glycyrrhizic acid was found at 250 nm using diode-array UV/VIS detector. The glycyrrhizic acid in BZYQT shows good linearity $(r^2>0.999)$ in the range of $15\;{\mu}g/ml$ to 500 ${\mu}g/ml$. The limit of detection (LOD) was less than 5 ng and R.S.D for intra-day and inter-day reproducibility was less than 7%. The mean recovery of the glycyrrhizic acid was $97.3{\sim}113.0%$. These results suggest that the developed HPLC method is simple and efficient, and could be contributed for the quality control of commercial BZYQT products.

• 한국정보과학회논문지:소프트웨어및응용
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• 제34권10호
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• pp.910-917
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• 2007

인간-로봇 상호작용에서 접촉은 인간에게 정서적 안정을 줄 수 있는 중요한 상호작용 방법 중 하나이다. 그러나 지금까지 음성과 영상을 기반으로 인간-로봇 상호작용이 이루어지는 연구가 대부분이었다. 본 논문에서는 접촉을 통한 인간-로봇 상호작용을 위해 인간의 접촉행동을 인식하는 방법을 제안한다. 제안한 인식 방법에서 인식 과정은 전처리 단계와 인식 단계로 나뉜다. 전처리 단계는 접촉감지부에서 생성된 데이타로부터 인식할 수 있는 특징들을 계산하는 단계이고 인식 단계는 인식기를 통해 접촉행동으로 분류하는 단계이다. 접촉감지부는 힘 센서인 FSR 센서를 이용하여 제작하였고 인식기는 신경망 모델인 다층퍼셉트론을 사용하였다. 실험은 남자 여섯 명에 의해 생성된 세 가지 접촉행동; '때리다', '쓰다듬다', '간질이다' 데이타를 가지고, 사람별로 인식기를 생성하여 cross-validation으로 평가한 결과 82.9%의 평균인식률을 보였고, 사람별 구분 없이 한 개의 인식기로 실험한 결과는 74.5%의 평균 인식률을 보였다.

• Journal of Electrical Engineering and Technology
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• 제12권5호
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• pp.1764-1776
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• 2017

To achieve economic stability, distribution Company as an economic institution should be managed by various processes. In this way, knowledge of different processes is the first step. Furthermore, expectations, outputs, requirement data, and sub-processes should be extracted and determined. Accordingly, to assign the performance responsibility of each process, the decision-making points must be introduced and, the deviation or change in set-points should be investigated into processes. Also, the performance of processes could be monitored by introducing of the sub-indictors. In this study, a practical method is presented for monitoring of reliability and power loss indices from viewpoint components' supply chain into the distribution network. At first, the visibility model of the supply chain is illustrated by focus group and the sub-indicators are extracted for each process of this chain. Then, validation and verification of the sub-indicators are accomplished by the Delphi method and, an information dashboard is presented by confirmed the sub-indicators and statistics methods. Finally, the proposed method is investigated by real data in a typical network and the results are analyzed.