• 대한전기학회:학술대회논문집
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• 대한전기학회 1979년도 하계 전자.전기연합학술발표회논문집
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• pp.80-82
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• 1979

While the standard linear-quadratic-Gaussian problem has fixed horizons, this paper considers the LQG problem with moving horizons. By the separation principle the solution will be given by the kalman filter with the approaching horizon and the LQ regulator with the receding horizon. Sufficient conditions on weighting matrices are derived under which the filter and regulator are asymptotically stable. It wall be shown that the computation method of the moving-horizon LQG regulators is better than that of the standard LQG regulator. The performance measure between the two optimal controls will be compared. A simulation result is given in order to show the usefulness of the moving-horizon LQG regulator.s

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.400.3-401
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• 2002

Levosulpiride is the levo-enantiomer from of racemic sulpride. abenzamide derivative selectively inhibition doparninergic D2 receptos at the trigger zone both in the central nervous system and in the gastrointestinal tract. We report a rapid and sensitive HPLC method using reverse phase C 18 column with fluorescence detection for separation and quantitation of levosulpiride in plasma. Tiapride was used as an internal standard. After adding an internal standard. levosulpiride in 800 ${\mu}l$ of plasma was extracted under basic conditions with ethyl acetate and methylene chloride. (omitted)

• Journal of Ginseng Research
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• 제44권5호
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• pp.680-689
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• 2020

Background: Peptides have diverse and important physiological roles in plants and are ideal markers for species identification. It is unclear whether there are specific peptides in Panax quinquefolius L. (PQ). The aims of this study were to identify Quinetides, a series of diverse posttranslational modified native peptides of the ribonuclease-like storage protein (ginseng major protein), from PQ to explore novel peptide markers and develop a new method to distinguish PQ from Panax ginseng. Methods: We used different fragmentation modes in the LTQ Orbitrap analysis to identify the enriched Quinetide targets of PQ, and we discovered Quinetide markers of PQ and P. ginseng using ultrahigh-performance liquid chromatography-quadrupole time-of-flight mass spectrometry analysis. These "peptide markers" were validated by simultaneously monitoring Rf and F11 as standard ginsenosides. Results: We discovered 100 Quinetides of PQ with various post-translational modifications (PTMs), including a series of glycopeptides, all of which originated from the protein ginseng major protein. We effectively distinguished PQ from P. ginseng using new "peptide markers." Four unique peptides (Quinetides TP6 and TP7 as markers of PQ and Quinetides TP8 and TP9 as markers of P. ginseng) and their associated glycosylation products were discovered in PQ and P. ginseng. Conclusion: We provide specific information on PQ peptides and propose the clinical application of peptide markers to distinguish PQ from P. ginseng.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2003년도 Proceedings of the international symposium on the fusion technology
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• pp.581-589
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• 2003

The variable flotation response ores from different deposits results basically from mineralogical association and their differences. Development of new techniques for analyzing the metallurgical performance of flotation and other concentration processes is demanded even in the treatment of rather simple ores such as porphyry ores. Diagnostic metallurgical analysis can be used to quantify the most possible recovery processes. Several porphyry copper/gold ores around the world were used to examine the responses in flotation, gravity separation and cyanidation in order to define the linkage between the recovery processes for both copper and old values. Laboratory batch flotation, gravity separation and cyanidation tests were carried out on these samples. All results were used to correlate the relative recovery of copper and gold, and to predict the highest possible metal recovery in the system. The metallurgical predictions were made according to the flotation conditions used and gravity separation. The results of various concentration processes on each porphyry ore samples are presented and discussed. All seven samples have shown significantly different gold/copper metallurgy. The grade/recovery relationships of gold and copper in the laboratory batch tests for the best results and the plants are given in the Figures below. The results of laboratory tests show that the copper recoveries converged to about $90\%$, but the gold recoveries were spread over $55-80\%$, except the K S ore. Series of standard cyanidation tests on the flotation concentrate samples and gravity separation using Knelson Separator on heads ores were carried out to cross-link the metallurgy and mineralogy of gold in the porphyry ores.

• Journal of Pharmaceutical Investigation
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• 제23권3호
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• pp.133-137
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• 1993

A high-performance liquid chromatographic assay using ion-pair reverse-phase system was developed for the separation of acebutolol and acebutolol acetyl metabolite in plasma. A ion-pair reversephase system consisting of an ODS-bonded silica column and a mixture of 20% $CH_3CN$, 0.1% $H_3PO_4$, 0.035 M heptanesulfonic acid and 0.005 M tetrabutylammonium hydrogen sulfate as the mobile phase were used. Triamterene was employed as an internal standard. Based on 0.2 ml of plasma, the detection limits were 10.4 ng/ml for acebutolol and 10.3 ng/ml of acebutolol acetyl metabolite at the signal-to-noise ratio of 3:1.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.279.2-280
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• 2003

A simple and accurate reverse-phase high performance liquid chromatography (HPLC) coupled with photodiode array was developed for the determination of dextromethorphan(DM) and its metabolite dextrorphan(DX) in human urine. Chromatographic separation was accomplished on a cyano analytical column at 220 nm using a mobile phase containing 25 mM triethylammonium phosphate buffer(PH 3.0) in a 0-70％ ACN gradient and triazolam(TZ) was used as internal standard(I.S). (omitted)

• 한국임상약학회지
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• 제10권1호
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• pp.38-41
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• 2000

A high-performance liquid chromatographic method with fluorometric detection was evaluated for analysis of ofloxacin in plasma. Biological fluids (plasma, $200\;{\mu}L$) were prepared for assay by protein precipitation with chlorofurm. The detection of ofloxacin and triamterene as an internal standard were performed at 358 nm for excitation and 495 nm for emission. The HPLC separation was carried out on Ultrasphere ODS column (4.6 mm${\times}25\;cm,\;5\;{\mu} m$) with acetonitrile $(45\%)$-phosphoric acid $(1.5\%)\;containing\;0.3\%$ sodium laurylsulfate as the mobile phase. The flow-rate was 1.0 mL/min. The calibration graphs were linear from 3.0 to 80 ng/mL with r=0.998. The minimal detectable concentration in plasma was 1.5 ng/mL. The proposed technique is reproducible, selective, reliable and sensitive.

• 한국항행학회논문지
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• 제21권4호
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• pp.359-364
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• 2017

현재 아날로그 방식의 마을방송 시스템은 기술 적용의 문제 및 시설 노후화로 인한 성능 저하 등의 문제로 인하여 무선 디지털 시스템으로의 전환과 이에 따른 시스템 표준이 요구되고 있다. 그러나 주파수 부족으로 인해 효율적인 디지털 무선 마을 방송 시스템의 구축을 위해서는 이웃마을간의 간섭분석이 중요하므로 여기서는 대표적인 간이무선국 dPMR(digital private mobile radio) 및 DMR(digital mobile radio) 방식을 고려하여 동일채널 간섭과 인접채널 간섭에 대한 시뮬레이션을 수행하였다. 동일채널 간섭분석에서는 마을간 이격거리와 인접채널 간섭분석에서는 주파수 오프셋을 사용하여 주파수 재사용 및 채널분리에 대한 본 논문의 결과는 향후 마을방송 표준개발과 시범 사업화를 위한 자료로 활용될 것이다.

• 분석과학
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• 제36권1호
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• pp.32-43
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• 2023

This study reports for the first time about a stability indicating RP-HPLC method for qualitative and quantitative determination of acalabrutinib in bulk and dosage form and in presence its impurities 1, 2 and 3. The chromatographic separation was carried on Zorbax XDB-C18 (250×4.6 mm; 5 µ id) as stationary phase, Phosphate buffer pH 6.4 and methanol 80:20 (v/v) as mobile phase at a flow rate of 1.0 mL/min, UV detection was carried at wavelength of 238 nm and the analysis was completed with a run time of 15 min. In these conditions the retention time of acalabrutinib and its impurities 1, 2 and 3 was observed to be 3.50, 4.83, 8.40 and 9.93 min respectively. The method was validated for system suitability, range of analysis, precision, specificity, stability and robustness. Spiked recovery at 50 %, 100 % and 150 % was carried for both standard and impurities and the acceptable % recovery of 98-102 was observed for acalabrutinib and both impurities studied and the % RSD in each spiked level was found to be less than 2. Stability tests were done through exposure of the analyte solution to five different stress conditions i.e expose to 1N hydrochloric acid, 1 N sodium hydroxide, 3 % peroxide, 80 ℃ temperature and UV radiation at 254 nm. In all the degradation condition, standard drug acalabrutinib was detected along with both the impurities studied and the degradation products were successfully separated. In the formulation analysis there is no other chromatographic detection of other impurities and formulation excipients. Hence the developed method was found to be suitable for the quantification of acalabrutinib and can separate and analyse impurities 1 and 2.

• FOCUS: LIFE SCIENCE
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• 제1호
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• pp.4.1-4.15
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• 2024

The Avantor® ACE® UltraCore series encompasses High Performance Liquid Chromatography (HPLC) and Ultra High Performance Liquid Chromatography (UHPLC) columns designed to deliver high throughput and high-efficiency ultra-fast separations. Utilizing ultra-inert solid-core silica particles with monodisperse particle distribution, these columns combine the high efficiency of UHPLC with the operability of HPLC instrumentation, yielding lower backpressure and high-resolution separations suitable for a broad spectrum of analytes. The Avantor® ACE® UltraCore range includes three primary product types: • UltraCore BIO: Designed for large biomolecules (≥5 kDa), these columns offer exceptional performance in separating biologically derived compounds. • UltraCore: Ideal for standard small organic molecules, providing rapid separations for both synthetic and natural mixtures. • UltraCore Super: Equipped with encapsulated bonding technology for small organic molecules in extreme pH conditions, optimal for high pH buffer requirements. The Avantor® ACE® UltraCore columns present a versatile and high-efficiency solution for chromatographic separation needs, accommodating a wide range of molecular sizes and providing enhanced resolution and reduced analysis time. Their adaptability to both HPLC and UHPLC systems, combined with the advantages of solid-core technology, makes them an invaluable tool in analytical and preparative chromatography.