• 제목/요약/키워드: Line poster

검색결과 16건 처리시간 0.021초

애자의 소음 분석을 통한 애자 고장 탐지 가능성 연구 (A Study on Possibility of Detection of Insulators' Faults by Analyses of Radiation Noises from Insulators)

  • 박규칠;윤종락;이재훈
    • 한국음향학회지
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    • 제28권8호
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    • pp.822-831
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    • 2009
  • 애자는 송전선 시스템에서 전기적으로나 기계적으로 매우 중요한 소자이다. 송전선 시스템에 설치된 이후 애자의 열화 등에 의해 고장이 난 애자를 찾아내기 위해 애자로 부터의 방사 소음을 측정하여 분석하였다. 대상으로 한 제품은 2종류의 현수 애자, COS, 2종류의 Line Poster, 피뢰기이며, 이들 제품의 정상 상태와 고장 상태의 방사 소음을 각각 측정하여 시간 파형, 주파수 스펙트럼, 피크 검출의 결과를 서로 비교하여 그 차이점을 제시하였다. 또한, 이를 바탕으로 방사 소음으로부터 고장 상태의 애자의 검출의 가능성 및 그 방법을 제시하였다.

Narrow-line region of two radio-quiet quasars

  • 오세명;우종학
    • 천문학회보
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    • 제36권1호
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    • pp.53.1-53.1
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    • 2011
  • We investigate the radial properties of the narrow-line region (NLR) in two radio-quiet quasars, PG1012+008 and PG1307+085, using the spectra obtained with the FORS1 at the Very Large Telescope. These high quality spectra with seeing < 0.6" enable us to extract seven two-pixel (0.4") spectra as a function of the radial distance from the accretion disk. In contrast to [OIII] narrow-band imaging, which can be contaminated by starbursts, shock-ionized gas, and tidal tails, we use emission-line diagnostic to determine the true size of the AGN-excited NLR. In this poster, we present the results based on the radial variance of $H{\beta}$ to [OIII] ${\lambda}5007$ ratio. For both targets, the [OIII] emission line exhibits a blue wing, suggesting an outflow of gas. In the case of PG1307+085, the blue wing disappears at the distance of 1". We will discuss the properties of the NLR in detail.

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SAMI Galaxy Survey Data Release 2: Absorption-line Physics

  • 오슬희
    • 천문학회보
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    • 제43권2호
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    • pp.53.1-53.1
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    • 2018
  • We present the second data release from the SAMI Galaxy Survey. The data release contains reduced spectral cubes for 1559 galaxies, about 50% of the full survey, having a redshift range 0.004 < z < 0.113 and a large stellar mass range 7.5 < log($M_*/M_{\odot}$) < 11.6. This release also includes stellar kinematic and stellar population value-added products derived from absorption line measurements, and all emission line value-added products from Data Release One. The data are provided online through Australian Astronomical Optics' Data Central. Our poster presents stellar/gas kinematics on the metallicity-mass plane and highlight several galaxies from the SAMI Galaxy Survey that have interesting stellar and gas kinematics. For more information about data release 2, please see: https://sami-survey.org/abdr.

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Near-Infrared Spectra of Super Star Clusters in M82

  • ;;임명신
    • 천문학회보
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    • 제37권1호
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    • pp.61.2-61.2
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    • 2012
  • We observed selected super cluster regions in M82 with 5'5 arcsec field-of-view using near-IR high resolution echelle spectrometer, IRCS, at the SUBARU 8.2 m telescope. The slit width of 0.15 arcsec makes the high resolution (R ${\approx}$ 20,000) spectra in the H and K bands. In this poster, we present sample spectra of [FeII] lines and ro-vibration lines of $H_2$ which trace ionic shocks in the intercloud regions and molecular shocks. The line widths of $Br{\gamma}$ line are also measured to derive the velocity dispersion within the super star clusters.

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Revealing ionized gas kinematics at the center of nearby Seyfert galaxies

  • Kim, Eun Chong;Woo, Jong-Hak
    • 천문학회보
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    • 제39권1호
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    • pp.43.2-43.2
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    • 2014
  • We investigate the ionized gas kinematics at the center of 6 nearby Seyfert galaxies, using the integral field spectroscopy data from the Calar Alto Legacy Integral Field spectroscopy Area survey Data Release 1. To understand the kinematic nature of the ionized gas in the narrow-line regions (NLRs), we measured the flux, velocity, and velocity dispersion of the [OIII] $5007{\AA}$ and Ha $6563{\AA}$ emission lines, after subtracting a best-fit stellar population model representing the stellar features. At the same time, we measured stellar velocity as a reference for the systemic velocity, and stellar velocity dispersion. We spatially resolved the velocity structure of the ionized gas using each emission line and compared it to that of stars. In this poster we present the flux, velocity, and velocity dispersion maps of the ionized gas and stars, and discuss the nature of the ionized gas outflows in the central kiloparsec scale.

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Tracing the earliest phases of star formation: A pilot survey of Planck Cold Clumps

  • Yi, Hee-Weon;Lee, Jeong-Eun;Liu, Tie;Kim, Kee-Tae;Wu, Yuefang
    • 천문학회보
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    • 제40권2호
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    • pp.54.1-54.1
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    • 2015
  • We observed 38 Planck Cold Clumps (PCCs) in the $850{\mu}m$ dust continuum emission using the JCMT/SCUBA-2, and detected the emission in 15 clumps containing dense cores. In this poster we present the preliminary results. The PCCs are cold, dense, and thus, they are considered as objects in the early evolutionary stages of star formation. The sources in our sample were selected based on the Purple Mountain Observatory (PMO) 13CO (1-0) integrated intensity maps. In order to examine whether these cores detected in $850{\mu}m$ continuum have potential to be prestellar cores, we compare each core mass estimated from the $850{\mu}m$ continuum with the Virial mass and Bonnor-Ebert (BE) mass calculated from the 13CO (1-0) or C18O (1-0) spectra. By comparing the two column densities from the dust continuum and the 13CO (1-0) or C18O (1-0) line, we also derive the CO depletion factor, which could be an indicator of core evolution. The moment maps of the 13CO (1-0) line are used to study the physical properties (e.g. kinematics, turbulence) of PCCs. We investigate difference between the sources with and without detectable $850{\mu}m$ emission to study the formation conditions of dense cores.

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Photometric Reverberation Mapping of Active Galactic Nuclei with Medium-band Filters and a Large FOV Telescope.

  • Hwang, Sungyong;Im, Myungshin;Ji, Tae-Geun;Lee, Hye-In;Pak, Soojong
    • 천문학회보
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    • 제42권2호
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    • pp.78.1-78.1
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    • 2017
  • We present a noble method to determine BH mass of many AGNs directly through reverberation mapping using a small telescope with wide-field of view. In 2017 August we installed five medium-band filters to a 0.25m diameter $5deg^2$ FOV telescope at the McDonald observatory. The width of these filters (FWHM ~ 50nm) are matched to the broad line width of type-1 AGNs at various redshifts. From recently obtained data, about r ~ 19 magnitude AGNs can be detected in line component with 150s exposure. With this magnitude limit, about 20~30 AGNs can be studied in one field. We plan to carry out at one day cadence observation over 20~30 fields, enabling us to monitor up to ~1000 AGNs over a wide range of variability. This poster presents out plan and early results from test observation.

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FLASH: The First Large Absorption Survey in HI with the Australian Square Kilometre Array Pathfinder

  • 윤혜인
    • 천문학회보
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    • 제45권1호
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    • pp.63.2-63.2
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    • 2020
  • FLASH is a blind neutral hydrogen (HI) absorption line survey, eventually targeting about 100,000 background radio continuum sources in the entire southern sky using the full 36-antenna of the Australian Square Kilometre Array Pathfinder (ASKAP). Our primary goal is to search for associated and intervening HI absorption lines in the intermediate redshift range 0.4 < z < 1.0. The survey aims to understand the evolution of HI gas in galaxies as well as various physical mechanisms in active galactic nuclei, such as accretion and feedback processes. In this poster, we give an overview of the FLASH survey and present the preliminary results from our first 100-hrs of pilot observations. The latest survey data covers 1,000 square degrees and is ideal for validating observation and data processing in the continuous 300MHz-width low frequency ASKAP band (700-1000MHz). One of the crucial objectives of the pilot survey is to establish the analysis methodology that will be applied to upcoming large absorption surveys in the future. We discuss our data quality validation and present some detections of associated/intervening HI absorption lines. These absorption lines allow us to trace the cold gas properties of active and normal galaxies at higher redshifts where the HI emission line is too weak to be detectable.

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Structure of the Galactic Foreground

  • Ahn, Hyeseong;Cho, Jungyeon
    • 천문학회보
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    • 제44권2호
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    • pp.68.4-68.4
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    • 2019
  • In this poster, we present a relation between the Galactic foregrounds and Galactic latitude to study the structure of the Galactic foregrounds. We propose that the standard deviation of observed values along a line of sight with Galactic latitude b ('σl.o.s') is inversely proportional to ${\sqrt{sin{\mid}b{\mid}}}$. To confirm this, we use synchrotron intensity data from the Planck archive and rotation measure (RM) data from the NVSS. We divided the sphere of the Galactic coordinate into bins with a constant surface area and calculated the average of standard deviation along Galactic latitude ('σlat'). We compared σlat ${\sqrt{sin{\mid}b{\mid}}}$ with σlat along Galactic latitude and found that σlat ${\sqrt{sin{\mid}b{\mid}}}$ is the most constant. These results support that the relation is reasonable.

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3D애니메이션을 활용한 수묵화기법 표현연구 (Research on the Expression of Ink-and-Wash Painting by using 3D Animation)

  • 한명희
    • 한국멀티미디어학회논문지
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    • 제13권7호
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    • pp.1105-1114
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    • 2010
  • 이 논문은 제13회 부산국제영화제(2008년10월2일부터10월10일까지 개최)조직위원회로부터 의뢰를 받아 필름으로 제작한 20초 분량의 공식트레일러 제작에 관한 연구결과를 요약한 것이다. 디지털콘텐츠 제작에서의 정체성과 방향성 확립이 필요한 시기에 한국적인 수묵채색화 기법을 3D Animation과 접목시켜 제 13회 부산국제영화제의 공식트레일러 제작에 활용하였다. 서양화가 신창식화백의 '아리랑_희망I(공식 포스터)를 모티브로 한국적인 수묵채색화의 특징을 고찰하여 모델링, 쉐이딩, 렌더링 단계에서 먹의 농담, 선의 강약, 수묵채색화의 색채요소를 디지털기법으로 어떻게 표현할 수 있는가에 대한연구결과 이다.