• Broadcasting and Media Magazine
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• v.16 no.4
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• pp.84-92
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• 2011

다성 음악 신호의 주요 멜로디 검출 기술은 프레임 단위로 다중 피치를 검색하고 멜로디 피치를 선택하여 최종 멜로디를 검출한다. 그러나 다중 피치 검색의 한계와 피치 검색에서의 더블링(doubling)과 하빙(halving) 등으로 인하여 멜로디 피치 검출의 정확도가 저하되는 문제점을 가진다. 따라서 다성 음악의 주요 멜로디 검출 과정은 프레임 사이의 멜로디 피치를 분석하여 추가적으로 멜로디 피치를 보정하는 과정이 필요하다. 본 고에서는 다성 음악 신호에서 프레임 단위로 검출된 멜로디 피치를 보정하여 주요 멜로디 검출의 정확도를 추가로 향상시키는 기술들을 소개한다. 다양한 기술들을 접근 방식에 따라 분류하여 설명하고, 대표적인 기술의 검출 정확도 향상 성능을 간단히 정리한다.

• Analytical Science and Technology
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• v.16 no.2
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• pp.125-133
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• 2003

In order to determine the contents of trans-resveratrol in red wine, which was mainly consumed in Korea, both LC/MS-ESI and LC/MS-APCI methods were used after solid-phase (Sep-Pak $C_{18}$-cartridges) extraction. The contents of trans-resveratrol obtained by LC/MS-ESI were detected in the range of $0.06-4.31{\mu}g/mL$. The recoveries were ranged from 88.4 to 97.9%. The values of relative standard deviation were ranged from 0.6 to 4.6% and the detection limit was $0.001{\mu}g/mL$. The contents of trans-resveratrol obtained by LC/MS-APCI were detected in the range of $0.09-4.02{\mu}g/mL$ and the detection limit was $0.005{\mu}g/mL$.

• Analytical Science and Technology
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• v.21 no.1
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• pp.53-57
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• 2008

In order to survey the contents of ethyl carbamate in alcoholic beverages, GC/MS-SIM method was used after extraction with dichloromethane in solid phase extract cartridge contained alcoholic beverages. In the applied GC/MS-SIM method, the values of recoveries and relative standard deviation were ranged from 85.2 % to 87.9 % and from 0.7 % to 1.9 %, the limit of detection and quantification were $2{\mu}g/kg$ and $10{\mu}g/kg$. Depending on alcoholic beverage kinds, the levels were variable and the average level was $194{\mu}g/kg$ for liquor, $105{\mu}g/kg$ for fruit wine, $62{\mu}g/kg$ distilled spirit, $28{\mu}g/kg$ for sake, $15{\mu}g/kg$ for yakju, $12{\mu}g/kg$ for other alcohol beverages, ND for soju, respectively.

• Bulletin of Food Technology
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• v.21 no.2
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• pp.49-54
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• 2008

농산물 중 잔류농약을 보다 쉽고 효율적으로 분석 할 수 있는 다성분 동시분석 방법에 따라서 UPLC-PDA을 이용하여 기기조건에 따른 검출한계 및 정량한계를 식품별 최저 MRL과 비교하여 유효성을 알아보고 회수율을 통하여 방법의 재현성을 조사한 결과 다음과 같다. 41종의 농약에 대한 검량선은 직선성이 우수하였으며 검출한계 $0.005{\sim}0.109mg/kg$으로 나타났으며 정량한계 는 $0.018{\sim}0.363ppm$으로 나타났다. Cycloprothrin 등의 경우처럼 검출기의 감응도가 최저 MRL 기준을 초과하는 농약에 대한 보완으로는 검출감도가보다 우수한 UV 검출기 등의 병행 활용이 필요하다. 회수율에 따른 재현성은 쌀의 경우 첨가 농도 0.4 mg/kg 일때 $62.09{\sim}99.58%$로 편차범위는 $1.03{\sim}13.92%$ 얻을 수 있었다.

• Analytical Science and Technology
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• v.22 no.6
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• pp.458-463
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• 2009

A new quantitative analytical method has been established for the rapid determination of flumethrin in honey products using high performance liquid chromatography (HPLC). Sample was dissolved and extracted in the mixture of water and acetonitrile (1:2). The extracts were purified with silica cartridge eluted by the mixture of hexane and dichloromethane (55:45) and analyzed at 266 nm using HPLC. The percentage recovery of flumethrin spiked in sample was found to be 90.2-97.8% and the limit of detection is 0.003 mg/kg. We validated the method for the linearity, the precision and the reproducibility. We investigated the residues of flumethrin in honey products retailed in market using the established method. Flumethrin was not detected at all among 130 samples of honey.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1219-1220
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• 2015

마이크로, 나노유체 (micro-, nanofluidics)을 이용한 종이 기반 분석 소자 (paper-based analytical devices, micro-PADs)에 대한 관심이 증가하고 있다. 종이 기반의 분석 소자는 초저가의 비용과 간단한 공정 방법으로 인하여 상용화 컨셉의 바이오센서로 각광받고 있다. 하지만, 종이 기반의 분석 소자는 낮은 검출 한계 (limit of detection, LOD)와 민감도 (sensitivity)의 제한이 있다. 그로 인해 우리는 이온 선택적 투과층 (ion permselective membrane, i.e. Nafion)을 종이 기반의 분석 소자와 결합하여 이온 농도 분극 (ion concentration polarization, ICP) 현상을 구현하여 낮은 검출한계와 민감도를 개선할 수 있었다. 접착력이 있는 테이프 표면에 이온 선택적 투과층을 패터닝 (patterning)하여 종이 기반 분석 소자와 결합하여 매우 간단하게 소자를 제작할 수 있었다. 따라서 종이 기반의 채널 양단에 직류 전압을 인가했을 때 발생하는 ICP 현상으로 인하여 형광 물질 (fluorescence dye)이 농축(preconcentration)되는 것을 확인할 수 있었다. 구체적으로, 초기 농도가 1.55 nM인 형광 물질을 이용하여 200 V의 외부전압을 인가했을 때, 500 초 이내에 1000 배 이상의 농축비를 얻을 수 있었다. 따라서, 외부 전압을 상용화된 건전지 출력값으로 낮출 수 있다면 다양한 종이 기반 분석 소자와 간단한 결합 방법을 통해 상용화 컨셉의 바이오센서로도 구현이 가능할 것이다.

• Food Engineering Progress
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• v.13 no.3
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• pp.195-202
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• 2009

This study was accomplished that analysis of seven polycyclic aromatic hydrocarbons (PAHs) in smoked or nonsmoked processing foods by high performance liquid chromatography (HPLC) with fluorescence detection. The calibration line was constructed with injected different levels of standard concentration. Limit of detection (LOD) and limit of quantification(LOQ) showed higher linearity ($r^{2}$=0.998) reasonably, and recovery exhibited 0.033-0.666 $\mu$g/kg, 0.108-2.217 $\mu$g/kg and 69.31-90.14%, respectively. As a result, the samples using smoked tuna as smoked materials contained seven PAHs with different range from 0.256 to 0.486 $\mu$g/kg. The benzo[a]pyrene, indicator of PAHs, was detected to below the LOQ in two samples. Concentrations of benzo[a]pyrene in three samples were below the 2 $\mu$g/kg which is the limit of regulation. Smoked tuna sauces were detected from 0.321 to 0.552 $\mu$g/kg and not detected in drying powders. PAHs of smoked meat products were ranged from 0.720 to 2.027 $\mu$g/kg and are higher than concentration of tuna smoked samples. PAHs were very low in non-smoked foods including mustard, herb, and roasted meats.

• Korean Journal of Food Science and Technology
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• v.32 no.5
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• pp.1009-1014
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• 2000

In order to detect pantothenic acid (PA), conditions for enzyme-linked immunosorbent assay (ELISA) were established. Anti-PA-BSA antibody was produced from rabbits immunized with PA-bovine serum albumin (BSA) conjugates which were prepared by the bromoacetyl chloride [Bc] method (PA-BSA[Bc]) and by the periodate oxidation [Po] method (PA-BSA[Po]). PA-BSA[Bc] and PA-BSA[Po] was used as a coating antigen for competitive indirect(ci)ELISA. The Anti-PA-BSA[Po] antibody on ciELISA showed no competitive reaction. The detection limit of PA by ciELISA using Anti-PA-BSA[Bc] antibody was 1 ppm. The Anti-PA-BSA[Bc] antibody showed little cross-reactivity to PA derivatives such as pantoyllactone, pantetheine, pantothenyl alcohol, and acetyl CoA. The detection limit of PA by microbiological assay (MBA) was 10 ppb. Assay recoveries of PA in egg, cow's liver, and lettuce by ciELISA were 109, 64, and 344%, respectively, comparing with the MBA results.

• Korean Journal of Food Science and Technology
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• v.42 no.5
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• pp.515-520
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• 2010

This research investigated benzimidazole residues (albendazole, fenbendazole, flubendazole, thiabendazole, oxibendazole) in livestock products. A total of 270 samples of livestock products (beef, pork and chicken) were purchased from local markets in Korea. Ethyl acetate was used to extract analytes from the sample, after which ethyl acetate extracts were purified using a MCX cartridge. Analytes were detected using liquid chromatography-tandem mass spectrometry. The limit of detection was 0.01-0.04 ppb, the limit of quantification was 0.03-0.13 ppb, the linearity ($r^2$) was 0.9992-1.0000, and the recovery was 70-85%. Residues of benzimidazoles, except for fenbendazole in pork, were not found in any of the 270 livestock samples. Fenbendazole was detected in the range of 1.2 to 3.1 ppb in 12 samples of pork.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.9
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• pp.1091-1096
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• 2017

The aim of this study was the validation of a modified analytical method for determination of oxypaeoniflorin and paeoniflorin in Moutan Cortex Radicis extract. For validation of the analytical method, we modified established analytical methods and validated improvement. For validation, the specificity, linearity, precision, accuracy, limit of detection (LOD), and limit of quantification of oxypaeoniflorin and paeoniflorin were measured by high performance liquid chromatography. The results show that the correlation coefficients of the calibration curve for oxypaeoniflorin and paeoniflorin were 1.0000 and 0.9998, respectively. The LOD for oxypaeoniflorin and paeoniflorin were $0.23{\mu}g/mL$ and $0.25{\mu}g/mL$, respectively. The inter-day and intra-day precision values of oxypaeoniflorin and paeoniflorin were 0.70~3.19% and 1.74~2.43%, and 0.32~0.92% and 0.62~2.28%, respectively. The inter-day and intra-day accuracies of oxypaeoniflorin and paeoniflorin were 98.33~102.11% and 97.72~118.12%, and 98.44~101.56% and 97.10~112.00%, respectively. Therefore, the analytical method was validated for the detection of oxypaeoniflorin and paeoniflorin in Moutan Cortex Radicis.