• 제목/요약/키워드: line spectrum

검색결과 609건 처리시간 0.026초

직렬 아크 및 코로나 방전의 주파수 스펙트럼 분석 (Frequency Spectrum Analysis of Series Arc and Corona Discharges)

  • 길경석;정광석;박대원;김선재;한주섭
    • 한국전기전자재료학회논문지
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    • 제23권7호
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    • pp.554-559
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    • 2010

  • In this paper, we analyzed the frequency spectrum of radiated electromagnetic pulses generated by series arc- and corona- discharges as a basic study to develop an on-line diagnostic technique for power facilities installed inside closed-switchboards. To simulate series arc and corona discharges, five types of electrode system which consists of needle and plane electrodes were arranged. The experiment was carried out in an electromagnetic shielding room, and the measurement system consists of an ultra log antenna and an EMI receiver. From the experimental results, the frequency spectrum exists in ranges from 30 MHz to 2 GHz for a series arc discharge and 30 MHz to 1.2 GHz depending on defects for a corona discharge. The peak frequency of the series arc- and corona- discharges were 100 MHz to 160 MHz and 40 MHz to 80 MHz, respectively.

  • https://doi.org/10.4313/JKEM.2010.23.7.554 인용 PDF KSCI

Soot 입자를 고려한 로켓 플룸의 적외선 스펙트럼 예측 (A Prediction of Infrared Spectrum of Rocket Plume with Considering Soot Particles)

  • 조성민;남현재;김덕현;권오준
    • 한국추진공학회지
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    • 제19권4호
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    • pp.24-36
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    • 2015

  • 본 연구에서는 복사 데이터베이스 기반의 LBL 모델과 근사 이론에 기초한 입자의 영향이 고려된 로켓 플룸의 적외선 스펙트럼 예측을 수행하였다. 로켓 플룸 내에 존재하는 가스 분자의 스펙트럼을 예측하기 위하여 고해상도 복사 데이터베이스를 이용하였다. 로켓 플룸 내에 존재하는 입자는 수트 입자로 모델링 하였으며 미 이론의 1항 근사 및 레일리 근사를 적용하였다. 두 이론의 적용에 대한 타당성을 검증하였으며, 이를 바탕으로 로켓 플룸의 적외선 스펙트럼을 예측하였다. 수트 입자의 영향을 고려함으로써 짧은 파장 영역 대에서 향상된 로켓 플룸의 스펙트럼 예측 결과가 도출되었다.

  • https://doi.org/10.6108/KSPE.2015.19.4.024 인용 PDF KSCI

Improved and quality-assessed emission and absorption line measurements in Sloan Digital Sky Survey galaxies

  • 오규석;;;이석영
    • 천문학회보
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    • 제36권2호
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    • pp.73.2-73.2
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    • 2011

  • We present a new database of absorption and emission-line measurements based on the entire spectral atlas from the Sloan Digital Sky Survey (SDSS) 7th data release of galaxies within a redshift of 0.2. Our work makes use of the publicly available penalized pixel-fitting(pPXF) and gas and absorption line fitting (gandalf) IDL codes, aiming to improve the existing measurements for stellar kinematics, the strength of various absorption-line features, and the flux and width of the emissions from different species of ionized gas. Our fit to the stellar continuum uses both standard stellar population models and empirical templates obtained by combining a large number of stellar spectra in order to fit a subsample of high-quality SDSS spectra for quiescent galaxies. Furthermore, our fit to the nebular spectrum includes an exhaustive list of both recombination and forbidden lines. Foreground Galactic extinction is implicitly treated in our models, whereas reddening in the SDSS galaxies is included in the form of a simple dust screen component affecting the entire spectrum that is accompanied by a second reddening component affecting only the ionised gas emission. Most notable of our work is that, we provide quality of the fit to assess reliability of the measurements. The quality assessment can be highly effective for finding new classes of objects. For example, based on the quality assessment around the Ha and [NII] nebular lines, we found approximately 1% of the SDSS spectra which classified as "galaxies" by the SDSS pipeline are in fact type I Seyfert AGN.

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PVRC 감쇠를 고려한 밀림관의 시간이력해석 (Time History Analysis of Surge Line Considering PVRC Damping)

  • 김태형;전장환;김종민;윤기석;김인용
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2006년도 정기 학술대회 논문집
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    • pp.1025-1032
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    • 2006

  • The PVRC(Pressure Vessel Research Council) damping is for the response spectrum analysis of the piping system. In this study, the possibility to apply it to the time history analysis is evaluated to reduce the higher conservatism for the structural integrity. The evaluation was performed for the surge line connecting the pressurizer to the hot-leg, and the whole mode includes the RCS and the building structures with the surge line. The analyses were performed using ANSYS code. The first modal analysis shows the modes of the surge line are isolated from those of the other structures. The composite modal damping was calculated with PVRC damping for the surge line and RG 1.60 damping for the other structures by using ANSYS routines. Of the calculated composite modal damping values, the composite modal damping values related to the modes of the surge line were replaced with the PVRC damping values with respect to its frequencies. With this replacement, the composite modal damping values of the other structures were not changed. Based on this decouple characteristics, the time history analyses for the seismic events with PVRC damping for the surge line were performed. And the results show the resultant loads can be reduced by up to 50%.

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