• Title/Summary/Keyword: source identification

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Source Estimation in Near-field by 2-Dimensional EM Scattering (2차원 전자파 산란에 따른 근방계에서의 소스 추정)

  • Kim, Tae Yong;Lee, Hoon-Jae
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2014.05a
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    • pp.59-60
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    • 2014
  • Non-destructive technique to measure internal structure and constant distribution of material can be widely used to exploration of mineral resources, identification of underground cables and buried pipelines, and diagnostic imaging in medical area. In this paper, we considered 2-dimensional EM scattering problem. Incident wave source is estimated by using some measured information obtained from near-field solutions.

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Submillimeter galaxies in the AKARI North Ecliptic Pole survey field

  • Lee, Dongseob;Kim, Yeonsik;Shim, Hyunjin
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.2
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    • pp.74.3-74.3
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    • 2019
  • SCUBA-2 North Ecliptic Pole survey, one of the ongoing JCMT large programs, is designed to obtain 850 ㎛ imaging data over ~4 deg2 around the NEP based on the AKARI NEP-Wide survey. By August 2019, the program is 50 % complete in terms of observing time, increasing the submillimeter coverage by a factor of 2 with the comparable depth. The rms measured in the deepest center is 0.92 mJy/beam, slightly above the 850 ㎛ confusion limit. With 4 σ detection, the source count is 50 % complete at 9 mJy. The surface density of submillimeter galaxies at this flux limit is 200 deg-2. Multi-wavelength identification of the 850 ㎛ sources was done through the likelihood analysis based on the far-infrared (250-500 ㎛), mid-infrared (18 ㎛), near-infrared (2-4 ㎛), and optical (i-band) source catalog. We are going to present morphologies and physical properties of 850 ㎛ selected submillimeter galaxies with the help of ancillary multi-wavelength datasets over the NEP area.

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Gravitational-wave EM Counterpart Korean Observatory (GECKO): Network of Telescopes and Follow-up Result for S190425z

  • Paek, Gregory SungHak;Im, Myungshin
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.2
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    • pp.76.2-76.2
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    • 2019
  • Recent observation of the neutron star merger event, GW170817, through both gravitational wave (GW) and electromagnetic wave (EM) observations opened a new way of exploring the universe, namely, multi-messenger astronomy (MMA). One of the keys to the success of MMA is a rapid identification of EM counterpart. We will introduce the strategy for prioritization of GW source host galaxy candidates. Our method relies on recent simulation results regarding plausible properties of GW source host galaxies and the low latency localization map from LIGO/Virgo. We will show the test results for both NS merger and BH merger events using previous events and describe observing strategy with our facilities for GW events during the ongoing LIGO/Virgo O3 run. Finally, we report the result of follow-up observation on, the first neutron star merger event, S190425z, during LIGO/VIrgo O3 run.

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Gravitational-wave Electromagnetic Counterpart Korean Observatory (GECKO): Network of Telescopes and Follow-up Observation of GW190425

  • Paek, Gregory S.H.;Im, Myungshin
    • The Bulletin of The Korean Astronomical Society
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    • v.45 no.1
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    • pp.36.3-37
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    • 2020
  • Recent observation of the neutron star merger event, GW170817, through both gravitational wave (GW) and electromagnetic wave (EM) observations opened a new way of exploring the universe, namely, multi-messenger astronomy (MMA). One of the keys to the success of MMA is a rapid identification of EM counterpart. We will introduce GW follow-up observation project in Korea for hunting GW EM counterpart rapidly and its strategy for prioritization of GW source host galaxy candidates. Our method relies on recent simulation results regarding plausible properties of GW source host galaxies and the low latency localization map from LIGO/Virgo. We will show a test result for both binary neutron star merger events using previous event and describe observing strategy with our facilities for GW events during the ongoing LIGO/Virgo O3 run. Finally, we report the results of optical/NIR follow-up observation of GW190425, the first neutron.

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Analyzing Preprocessing for Correcting Lighting Effects in Hyperspectral Images (초분광영상의 조명효과 보정 전처리기법 분석)

  • Yeong-Sun Song
    • Journal of the Korean Society of Industry Convergence
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    • v.26 no.5
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    • pp.785-792
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    • 2023
  • Because hyperspectral imaging provides detailed spectral information across a broad range of wavelengths, it can be utilized in numerous applications, including environmental monitoring, food quality inspection, medical diagnosis, material identification, art authentication, and crime scene analysis. However, hyperspectral images often contain various types of distortions due to the environmental conditions during image acquisition, which necessitates the proper removal of these distortions through a data preprocessing process. In this study, a preprocessing method was investigated to effectively correct the distortion caused by artificial light sources used in indoor hyperspectral imaging. For this purpose, a halogen-tungsten artificial light source was installed indoors, and hyperspectral images were acquired. The acquired images were then corrected for distortion using a preprocessing that does not require complex auxiliary equipment. After the corrections were made, the results were analyzed. According to the analysis, a statistical transformation technique using mean and standard deviation with reference to a reference signal was found to be the most effective in correcting distortions caused by artificial light sources.

A Study on Identification of Source Using SEM-EDX by Analysis of shape and chemical composition in individual Particles (SEM-EDX법을 이용한 개별입자의 형상과 화학적 조성 분석을 통한 발생원 추정에 관한 연구)

  • 염해진;전보경;최금찬
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2003.05b
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    • pp.320-321
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    • 2003
  • 대기중에 존재하는 입자상물질은 광범위한 입경역에 걸쳐서 다종다양한 미량화학성분으로 구성되는 분산체이고, 그 성상은 공간적으로도 시간적으로도 크게 변동한다. 입자상 물질의 화학분석법은 발생원 동정을 위한 자료로 적합하며 일반적으로는 습식의 파괴적인 원소분석으로 하는 경우가 많다. 일반적으로 화학적 분석법은 개별입자의 정보가 무시되며 필터에 포집된 bulk 시료에 의한 분석이 진행되므로 장시간 포집에 의한 단시간의 시간변동과 개개의 입자가 가지는 정보가 무시되고 평균화 되어버린다. (중략)

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Distribution and Source Identification with Particle Size(Fine and Coarse) of Air Particles in Daejeon Region(∥) (대전지역 대기분진의 입경별 원소분포와 통계적 오염원 분류(∥))

  • 문종화;김선하;임종명;정용삼
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2003.05b
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    • pp.295-296
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    • 2003
  • 최근 환경오염에 대한 인식과 규제가 증가하고 쾌적한 주변환경에 대한 관심이 높아짐에 따라 대기, 물, 토양, 생물 등과 같은 여러가지 환경시료의 분석을 통하여 오염의 정도를 파악하고 오염원을 규명하여 환경관리정책에 반영하려는 노력이 추진되고 있다. 여러 가지 환경시료중 대기분진은 자연적 또는 인위적 발생원에 따라 다양한 원소들을 함유하고 있기 때문에 대기환경지표시료로 이용되고 있다. 오염원의 규명을 위한 소량의 휠터상 분진시료로부터 원소의 정확한 분석은 필수적이고 중요한 선행작업이며 적합한 측정분석법의 이용이 요구된다. (중략)

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A System Development for the Identification of Underwater Sound Source and the Support of Acoustic Rscognition Training (수중 음원 식별 및 청음훈련 지원 시스템 개발)

  • Bang, Bok-Dong;Jung, Sung-Hwan
    • Annual Conference of KIPS
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    • 2003.11a
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    • pp.45-48
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    • 2003
  • 수중 음원의 식별은 수중전에서 매우 중요한 요소이다. 수중 음원의 식별을 위해 신호의 획득, 처리 및 분석과 청음훈련을 지원할 수 있는 시스템을 개발하였다. 실제 사용되고 있는 다양한 종류의 소나(SONAR) 장비 상호간 및 육상 지원 장비간의 호환성 문제와 경제성을 고려하여 PC기반 체계로 개발하였다. 개발된 시스템은 선박별 장치별 음파의 특징 추출이 가능하며 개별 장치의 특징이 두개이상 복합적으로 나타날 때에도 가능하다.

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