• Journal of Advanced Marine Engineering and Technology
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• 제31권8호
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• pp.1028-1034
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• 2007

In order to establish a criteria of solid particle separation performance test on marine centrifugal purifier at factory acceptance test, an investigation had been done on criteria of test standards, regulations and test specifications of purifier manufactures. KS V 7836, fuel oil and lubricating oil purifiers for marine use-centrifugal type, the criteria of solid particle separation is studied in the point of reality, restricts and analysis method. It is proposed that a reasonable criteria and analysis method should be adopted, and the current criteria shall be revised to adequate levels considering reasonable basis and industrial technology levels. Also, the test analysis conceptions, separation efficiency method and particle size restriction method, are reviewed to fulfil separation performance test for marine centrifugal purifiers.

• 한국항공우주학회지
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• 제49권7호
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• pp.565-572
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• 2021

본 연구에서는 국방 분야에서 분리장치로 사용되고 있는 파이로 장치 중 장기간 보관된 폭발볼트의 성능 및 노화에 관한 연구를 수행하였다. 연구를 위해 약 10년간 무기체계에 탑재되어 있던 폭발볼트를 확보하였으며, AIAA Standard 및 MIL-STD를 기반으로 성능 및 수명 평가 절차를 수립하였다. 성능 평가를 위해 먼저 비기능 검사를 수행하여 외적인 변화나 고장이 발생하였는지 확인하였으며, 내부 회로 및 구조에 이상이 없는지 회로검사와 X-ray 검사를 수행하였다. 비기능 검사가 통과된 시료에 대해서 작동 확인을 위한 성능 시험을 실시하였다. 성능 시험을 통해 폭발볼트의 분리 여부 및 분리시간을 측정하였으며, 일부 시료의 경우 잔여 수명 및 연장 가능성을 확인하기 위해 고온저장시험 후 성능 시험을 실시하였다. 마지막으로 시험 결과와 아레니우스 모델을 바탕으로 잔여 수명 및 신뢰도를 예측하였으며, 수명에 따른 신뢰도를 확인하였다.

• 분석과학
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• 제17권2호
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• pp.184-191
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• 2004

본 연구에서는 HRGC/HRMS에 의한 다이옥신분석에 있어 가장 널리 사용되고 있는 SP-2331 및 DB-5MS 컬럼에 의한 독성 2,3,7,8-다이옥신 동족체 분리의 영향에 대하여 조사하였다. 컬럼분리성능평가 표준용액과 비산재 시료의 분석을 통하여 이들 컬럼에 의한 tetra, penta 및 hexa-2,3,7,8-동족체의 분리에 대한 부분과 I-TEQ값의 영향을 중심으로 설명하였다. 이들 두 컬럼에 의한 분석에서 컬럼분리성능평가 표준용액의 경우 DB-5MS에 의해서는 총 2,3,7,8-치환이성체의 농도는 508.4 ng/mL로 나타났으며, SP-2331에 의해서는 515.8 ng/mL로 나타났다. 이들을 I-TEQ값으로 환산하였을 때 거의 동등하게 나타났다. 비산재 시료의 경우에서도 이들 두 컬럼에 의한 2,3,7,8-치환이성체의 총 농도와 I-TEQ값이 거의 비슷하게 나타났다.

• 한국항공운항학회지
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• 제20권4호
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• pp.14-20
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• 2012

A properly determined separation minima applied in Air Traffic Management(ATM) is critical for safe and efficient aircraft operations. The separation minima is primarily determined by the accuracy performance of surveillance system, and, due to the stringent aviation safety standard, the position accuracy of the surveillance system must be estimated with a high level of reliability. This study proposed a method for estimating the position accuracy of surveillance system with a relatively small amount of data by finding upper confidence limit instead of maximum likelihood values of unknown parameters. Through the proposed method, it is possible to determine a required separation minima with a more reliability in the face of data scarcity which often occurs when we implement a new surveillance system such as Automatic Dependent Surveillance-Broadcast (ADS-B).

• Journal of Advanced Marine Engineering and Technology
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• 제31권6호
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• pp.804-809
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• 2007

In order to provide reliability. reproducibility. objectivity of solid particle separation performance test on marine centrifugal purifier, an investigation had been done on solid test dusts. test standards and designation of a definite standard test dust In test specifications or standards. ISO 121031-1 A2 test dust is the best test particle to meet commercial and military fuel oil and lube oil requirements on marine standards.

• 대한전자공학회논문지TC
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• 제44권11호
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• pp.25-32
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• 2007

본 논문에서는 RFID Tag 충돌방지를 위한 Group Separation 알고리듬에 대해 연구 하였다. 이를 위해 기존의 RFID Tag 충돌방지 기법인 ALOHA기반의 기법과 이진 검색 충돌방지 기반의 알고리듬을 먼저 비교 분석하였다. 기존 알고리듬은 태그를 인식하기 위한 탐색횟수와 전송하는 데이터량을 감소시키는데 한계점을 가지고 있었다. 제안한 Group Separation 알고리듬은 인식범위 내의 태그를 구별하기 위해, 태그 ID의 1의 개수에 따라 그룹을 나누어 검색한다. 검색 초기에 식별 그룹을 세분화하였으므로 각 그룹의 호출에 응답 가능한 태그 ID의 개수는 크게 줄어들 뿐만 아니라 간단한 연산과정으로 쉽게 예상이 가능하다. 리더는 검색 이전에 각 그룹에서 발생 가능한 충돌 지점과 그에 따른 태그 ID를 산출하여 테이블로 구성하여 메모리에 저장하고, 충돌이 발생하면 메모리의 충들 테이블에서 충돌 지점에 따른 태그 ID를 검색한다. 알고리듬의 성능평가는 태그를 인식하기 위한 리더의 반복횟수와 전송 데이터 량으로 나타내었다. 성능평가 결과, 기존의 알고리듬과 비교하여 Group Separation 알고리듬의 반복횟수가 최대 20.4% 감소되었고, 전송 데이터 량도 1/4.5배 감소된 것을 확인할 수 있었다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1991년도 추계학술대회 논문집
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• pp.105-109
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• 1991

A computer aided flatness calibration system has been developed. Rectangular grids based measurement procedure is proposed with closing error technique. giving advantages over conventional diagonal measurement procedures (‘Union Jack’). A new analysis technique has been developed for flatness evaluation called ‘ETT(Enclose Tilt technique)’, enabling minimum separation definition which is acknowledged as standard term for flatness definition. Practical assessment shows the performance of the developed system.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 추계학술대회 논문집
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• pp.375-378
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• 2002

In this paper, the frequency response separation scheme is proposed for high scanning speed and simple structure of non-contact type of AFM. A self-sensing cantilever is attached on the actuator for detect the atomic force between tip and the media surface. VCM or PZT are used for actuator. This paper presents the method to simplify the actuator structure and the performance of each actuator for non-contact type AFM. Based on the frequency response separation scheme, the only one actuator plays roles 1311owing low frequency surface and modulating self-sensing cantilever tip in contrast with convention non-contact type AFM. 10 ${\mu}{\textrm}{m}$ standard grid sample imaged to verify proposed scheme. This result shows the possibility simplifying the actuator structure and reducing cost of non-contact type AFM.

• Environmental Analysis Health and Toxicology
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• 제29권
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• pp.18.1-18.9
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• 2014

Objectives The purpose of this study was to determine a separation method for each arsenic metabolite in urine by using a high performance liquid chromatography (HPLC)-inductively coupled plasma-mass spectrometer (ICP-MS). Methods Separation of the arsenic metabolites was conducted in urine by using a polymeric anion-exchange (Hamilton PRP X-100, $4.6mm{\times}150mm$, $5{\mu}m$) column on Agilent Technologies 1260 Infinity LC system coupled to Agilent Technologies 7700 series ICP/MS equipment using argon as the plasma gas. Results All five important arsenic metabolites in urine were separated within 16 minutes in the order of arsenobetaine, arsenite, dimethylarsinate, monomethylarsonate and arsenate with detection limits ranging from 0.15 to $0.27{\mu}g/L$ ($40{\mu}L$ injection). We used G-EQUAS No. 52, the German external quality assessment scheme and standard reference material 2669, National Institute of Standard and Technology, to validate our analyses. Conclusions The method for separation of arsenic metabolites in urine was established by using HPLC-ICP-MS. This method contributes to the evaluation of arsenic exposure, health effect assessment and other bio-monitoring studies for arsenic exposure in South Korea.

• Bulletin of the Korean Chemical Society
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• 제27권4호
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• pp.519-523
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• 2006

Poly(dimethyl siloxane) (PDMS) has been employed as a microchip material for DNA separation in microfluidic condition. Different sieving molecules such as cellulose derivatives having glucose building block (methyl cellulose (MC), hydroxyethyl cellulose (HEC), and hydroxypropyl methyl cellulose (HPMC)) and polyethylene oxide (PEO) having linear (ring-opened ethylene oxide) unit were used and their performance was compared in terms of separation efficiency and resolution. In general, PEO showed better separation performance than cellulose derivatives probably due to the nature of linear shape polymer conformation. It was possible to perform at least 15 consecutive running with 1.2% PEO at the electric field strength around 200 V/cm. Fast analysis of the standard $\Phi$X 174 RF DNA/Hae III (less than 130s) was obtained with the number of the theoretical plate around 250,000/m. Our PMDS microchip was applied to the measurement of CAG repeat number, which is related to male infertile disease.