• Bulletin of the Korean Chemical Society
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• 제34권11호
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• pp.3284-3288
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• 2013

This paper describes first development and validation of pentafluorophenylprophyl ligand-based liquid chromatography coupled to tandem mass spectrometry (PFPLC-MS/MS) method to determine metformin, a highly polar compound, in human plasma. Metformin and Phenformin (internal standard) were extracted from human plasma 50 ${\mu}L$ with a single-step protein precipitation. The chromatographic separation was performed using a linear gradient elution of mobile phase involving 5.0 mM ammonium formate solution with 0.1% formic acid (A) and acetonitrile (B) over 3.0 min of run time on a Phenomenex Luna PFP column. The detection was performed using a triple-quadrupole tandem mass spectrometer (Waters Quattro micro) with electrospray ionization in the mode of positive ionization and multiple-reaction monitoring (MRM). The developed method was validated with 5.0 ng/mL of lower limit of quantification (LLOQ). The calibration curve was linear over 5-3000 ng/mL of the concentration range ($R^2$ > 0.99). The specificity, selectivity, carry-over effect, precision, accuracy and stability of the method met the acceptance criteria. The method developed in this study had had rapidness, simplicity and ruggedness. The reliable method was successfully applied to high throughput analysis of real samples for a practical purpose of a pharmacokinetic study.

• Journal of the Korean Data and Information Science Society
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• 제17권2호
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• pp.335-344
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• 2006

The purpose of this paper is to apply data mining method for the inbound call center optimization. Data mining analysis is come to be used in order to predict the degree of difficulty on the consultation. It is the method of maximal efficiency for the call center that uses of the predicted degree of difficulty and customer grade as routing which hits to the skill of the consultation unit. This method is to get the possibility of efficiency for the call center with the maximum efficiency.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2017년도 추계학술발표회
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• pp.135-135
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• 2017

• 대한족부족관절학회지
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• 제21권1호
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• pp.33-38
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• 2017

Purpose: The patient-reported outcome measure (PROM) is used to quantify the subjective state of patients before and after the treatment. The electronic method was recently developed and used for the completion of PROM, in addition to the conventional paper and pencil method. This study identified whether the results of Foot Function Index (FFI) and Foot and Ankle Outcome Score (FAOS) using the paper and pencil method was different from those using the electronic method. Materials and Methods: Between May 2016 and August 2016, 42 patients who were admitted to the Seoul Foot and Ankle Center two days before surgery were included for evaluation. The mean age was 46 years (range, 21~72 years). There were 29 males and 13 females. To use the electronic method, the PADAS software (PADAS, Seoul, Korea) was implemented using a touch pad. The primary trial of FFI and FAOS was performed using either the paper-and-pencil method or the electronic method. At 24 hours after the primary test, a secondary trial of FFI and FAOS was performed using the other method. Then, we identified the reliability of FFI and FAOS between the two methods by calculating the intraclass coefficient. Results: Twenty-two patients underwent the first trial using the paper-and-pencil method, and 20 patients underwent the first trial using the electronic method. Of the 42 patients, 8 patients were excluded from this study and only 34 patients were included in this study. The reliability of FFI was excellent with an intraclass coefficient of 0.957, and the reliability of FAOS was also excellent with an intraclass coefficient of 0.840. Conclusion: The paper-and-pencil method and the electronic method have the same result for the completion of FFI and FAOS in this study. Therefore, it is commonly considered that the completion of FFI and FAOS using the electronic method can be applied in practice.

• Bulletin of the Korean Chemical Society
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• 제31권6호
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• pp.1751-1752
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• 2010

• 약학회지
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• 제55권4호
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• pp.284-288
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• 2011

The test method for biologics of lot release system is based on 'Test procedure and specification for biological products,' generally, thimerosal content is measured by chemical analysis using O.D. In this study, the comparative analysis was carried out using the gold amalgamation method for thimerosal content was compared to the existing methods, which are described above. The gold amalgamation method, which uses atomic absorption spectrophotometry, was meets all the method validation acceptance criteria. It is considered to be proper as the assay and identification test for thimerosal. In this study, the comparative analysis was performed three times. As a result, gold amalgamation method is more convenient and easy to perform as this assay doesn't have pre-treatment procedure. Also this assay showed good precision and reproducibility compared to the conventional method. Therefore, it is appropriate to alternate the assay method of thimerosal from the conventional chemical analysis to gold amalgamation method to improve the credibility of lot release system and the quality control of biologics, by standardizing test method.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2008년도 추계학술대회 논문집
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• pp.345-348
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• 2008

Metallic bipolar plate for molten carbonate fuel cell(MCFC) is composed of the shielded slot plate and the center plate. Among these, the center plate plays an important role in gas sealing. Therefore, manufacturing of the center plate is considered one of the key issues in MCFC. The center plate is manufactured by bending process. In bending process, springback and recoiling are two main problems. The aim of this article is to optimize the bending process of the center plate regardless of springback and recoiling. To achieve this goal, we proposed the punch having step to reduce springback and recoiling. Using finite element method and $L_9$ orthogonal array, we determined the main factors in the center plate bending process. And we found the optimal bending process condition for the MCFC center plate.

• Journal of Information Display
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• 제3권4호
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• pp.1-3
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• 2002

The antiferroelectric liquid crystal display (AFLCD) is a unique display that can at demonstrate a moving image perfectly the passive matrix driving scheme. We optimised driving the waveform and introduced a dual-driving method. Also, by improving this driving method and using line inversion method, we realize the AFLC display of high image quality with $160(RGB){\times}240$, 32768 colors, crosstalk free and flicker free contrast ratio is greater than 60:1, and the brightness is above 200 $cd/m^2$.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
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• pp.1323-1326
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• 2007

A new driving method employing 2-dimensional spatial averaging is proposed. This method successfully eliminates the vertical line artifact caused by luminance difference from unbalanced charging voltage between polarities. This spatial averaging method can secure charging time, minimize driver heating, and achieve higher display quality.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.47-50
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• 2008

We propose a new method evaluating the image quality of display devices using the CIECAM02 that is the recently developed CIE color appearance model and provides an extension of the previously recommended CIE color spaces. We develop the evaluation method that quantifies the color reproduction capability, emotional gray scale (gradation), and visual perception contrast (perceptual contrast range) based on the gamut in this model.