• Nuclear Engineering and Technology
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• 제48권2호
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• pp.419-433
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• 2016

One of the important severe accident management measures in the Light Water Reactors is water injection to the reactor core. The related phenomena are investigated by performing experiments and computer simulations. One of the most widely known is the QUENCH test-program. A number of analyses on QUENCH tests have also been performed by different computer codes for code validation and improvements. Unfortunately, any deterministic computer simulation is not free from the uncertainties. To receive the realistic calculation results, the best estimate computer codes should be used for the calculation with combination of uncertainty and sensitivity analysis of calculation results. In this article, the QUENCH-03 and QUENCH-06 experiments are modelled using ASTEC and RELAP/SCDAPSIM codes. For the uncertainty and sensitivity analysis, SUSA3.5 and SUNSET tools were used. The article demonstrates that applying the best estimate approach, it is possible to develop basic QUENCH input deck and to develop the two sets of input parameters, covering maximal and minimal ranges of uncertainties. These allow simulating different (but with the same nature) tests, receiving calculation results with the evaluated range of uncertainties.

• 한국군사과학기술학회지
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• 제23권4호
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• pp.346-354
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• 2020

Nowadays, it is required to apply low observable technology to weapon systems in operation or under development. Radar Cross Section(RCS) is a measure of the scattered power in an given direction when a target is illuminated by an incident wave and used as a parameter to estimate the low observable performance of weapon system. RCS of a target can be calculated by various numerical methods. However, measurement is also needed to estimate RCS of a complex target because it is difficult to estimate theoretically. To acquire reliable measurement results, an analysis of measurement uncertainty is essential. In this paper, error components and uncertainties of near-field RCS measurement system which was constructed in ASTEC(Aerospace System Test & Evaluation Center) were analyzed based on the IEEE recommended practice for radar cross-section test procedures(IEEE Std. 1502-2007) which describes the uncertainty of RCS measurement and unique error components of this near-field measurement system were also identified.

• 한국환경복원기술학회지
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• 제7권5호
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• pp.94-99
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• 2004

This study was carried out to find out what is the optimum conditions for RAPD of Zelkova serata. We changes the factors what affect to PCR band patterns, as a result, we established the optimum conditions as follows; template DNA 100mg, Primer 0.25uM, dNTP 100mM, Taq polymerase 1.0u, and total reaction volume was filled up to 10uL with distilled water. As the amount of primers went higher, PCR reaction rates were lowered. This reason was cause by exhaustion of primers during initial reaction. The amount of dNTP didn't showed noticable differtations between the range, but the optimum amount was 100mM for efficiency. Taq polymerase 1.0 unit was the best in the range. As the concentration of polymerase were increased, many non-specific bands were appeared, In primer selection, most Openron Random Primers are amplified in this experiment. The primers GC contents were 60, and set A, B, C, D, E, X were tested. Thermal cycler(ASTEC PC808, Japan) condition was, $95^{\circ}C$, 5min, initial denaturation, $94^{\circ}C$, 20sec, denaturation, $37^{\circ}C$, 40sec, annealing, $72^{\circ}C$, 1min, extention, 45cycle repeated and final extention $72^{\circ}C$10min.

• 분석과학
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• 제32권5호
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• pp.163-172
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• 2019

Methamphetamine (MA) is currently the most abused illicit drug in Korea and its major metabolite is amphetamine (AP). As MA exist as two enantiomers with the different pharmacological properties, it is necessary to determine their respective amounts in a sample. Thus a chiral stationary phase liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed for identification and quantification of d-MA, l-MA, d-AP, and l-AP in human urine. Urine sample ($200{\mu}L$) was diluted with pure water and purified using solid-phase extraction (SPE) cartridge. A $5-{\mu}L$ aliquot of SPE treated sample solution was injected into LC-MS/MS system. Chiral separation was carried out on the Astec Chirobiotic V2 column with an isocratic elution for each enantiomer. Identification and quantification of enantiomeric MA and AP was performed using multiple reaction monitoring (MRM) detection mode. Linear regression with a $1/x^2$ as the weighting factor was applied to generate a calibration curve. The linear ranges were 25-1000 ng/mL for all compounds. The intra- and inter-day precisions were within 3.6 %, while the intra- and inter-day accuracies ranged from -5.4 % to 11.8 %. The limits of detection were 2.5 ng/mL (d-MA), 3.5 ng/mL (l-MA), 7.5 ng/mL (d-AP), and 7.5 ng/mL (l-AP). Method validation parameters such as selectivity, matrix effect, and stability were evaluated and met acceptance criteria. The applicability of the method was tested by the analysis of genuine forensic urine samples from drug abusers. d-MA is the most common compound found in urine and mainly used by abusers.

• 자원리싸이클링
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• 제30권4호
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• pp.3-10
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• 2021

도시광산의 대표적인 사례인 폐 전자부품 재활용 분야는 유용한 선별기술의 개발이 필요하다. 본 연구에서는 전자부품들을 4개의 그룹으로 선별하기 위해 딥러닝에 의한 이미지 식별을 기반으로 한 선별기를 개발하였다. 전자부품들은 폐 인쇄회로기판으로부터 회수되었으며, 처리 후 차이점에 따라 분리되어야 한다. 선별기는 GPU, 카메라, 컨베이어벨트, 공기 압축기로 이루어진 워크스테이션으로 구성되어있다. 컨베이어벨트(벨트 속도: 6cm/s) 위에 있는 작은 크기(3.5cm 이하)의 전자부품들을 데이터로 가져와 학습했다. 이미지 식별의 정확도는 종류에 따라 96%, 그리고 그룹에 따라 99%였다. 벨트속도와 압축공기의 블로다운 시간과 같은 작동조건에 변화를 주었을 때, 이미지 식별의 정확도 그리고 블로다운에 의한 회수율을 측정하여 선별의 최적 조건을 결정했다. 최적조건에서 이미지 분류의 정확도는 그룹별로 98.7%였다. 선별 효율은 70% 이상이었다.

• Clinical and Experimental Pediatrics
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• 제51권10호
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• pp.1071-1076
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• 2008

목적: RSV 호흡기 바이러스 감염은 해마다 영유아에서 심한 호흡기 질환의 중요한 원인이 되고 있다. 이에 따라 최근 검사 방법이 간편하고 결과를 빨리 알 수 있는 면역 크로마토그래피법이 신속 항원 검사법으로서 소개되어 그 정확성과 임상에서의 유용성이 많이 연구되고 있으나 국내에서는 연구례가 드문 실정이다. 이에 저자들은 이 검사법의 정확성과 유용성을 평가하여 실질적인 검사법으로 정착시키고자 하였다. 방법: 2007년 4월부터 2008년 3월까지 발열, 기침, 천명, 호흡곤란, 빈호흡 등의 증상으로 외래 내원 및 입원치료를 받은 112명의 환아를 대상으로 비인두 가검물을 채취하여 RSV Respi-Strip과 효소 면역 측정법, RT-PCR(ASTEC)을 동시에 시행하였다. RT-PCR을 표준으로 하여 RespiStrip 과 EIA의 결과를 비교 분석하여 정확성과 유용성을 평가하였다. 결 과: RSV RespiStrip, RT-PCR, EIA에 양성을 보인 환아는 각각 42명, 45명, 39명 이었다. RespiStrip는 RT-PCR 검사법에 대하여 민감도 88%, 특이도 94%, 양성 예측도 90%, 음성 예측도는 92% 였으며 위양성률과 위음성률 그리고 일치도가 각각 5.9%, 11%, 83% 로 나왔다. EIA는 RT-PCR 검사법에 대하여 민감도 84%, 특이도 94%, 양성 예측도 90%, 음성 예측도 90%, 일치도 79% 로 나왔다. 결론: 신속 항원 검사가 비교적 민감도가 높으므로 RSV 감염의 선별 검사로서 적합하다고 생각한다. 외래 진료실에서 빠르고 경제적이며 간편하게 검사하여 조기에 적절한 치료를 함으로써 합병증을 예방할 수 있고 아울러 불필요한 항생제의 사용을 줄일 수 있다. 앞으로 이러한 신속검사가 실제 임상에서 많이 적용되리라 기대된다.