• 제목/요약/키워드: Detection Space

검색결과 1,638건 처리시간 0.029초

Development of state-of-the-art detectors for X-ray astronomy

  • Lee, Sang Jun;Adams, J.S.;Audley, H.E.;Bandler, S.R.;Betancourt-Martinez, G.L.;Chervenak, J.A.;Eckart, M.E.;Finkbeiner, F.M.;Kelley, R.L.;Kilbourne, C.A.;Porter, F.S.;Sadleir, J.E.;Smith, S.J.;Wassell, E.J.
    • 천문학회보
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    • 제40권1호
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    • pp.53.3-54
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    • 2015
  • We are developing large arrays of X-ray microcalorimeters for applications in X-ray astronomy. X-ray microcalorimeters can detect the energy of X-rays with extremely high resolution. High-resolution Imaging spectroscopy enabled by these arrays will allow us to study the hot and energetic nature of the Universe through the detection of X-rays from astronomical objects such as neutron stars or black holes. I will introduce the state-of-the-art X-ray microcalorimeters being developed at NASA/GSFC and the future X-ray observatory missions based on microcalorimeters.

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MULTISENSOR SATELLITE MONITORING OF OIL POLLUTION IN NORTHEASTERN COASTAL ZONE OF THE BLACK SEA

  • Shcherbak, Svetlana;Lavrova, Olga;Mytyagina, Marina;Bocharova, Tatiana;Krovotyntsev, Vladimir;Ostrovskiy, Alexander
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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    • pp.989-992
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    • 2006
  • The new approach to the problem of oil spill detection consisting in combined use of all available quasiconcurrent satellite information (AVHRR NOAA, TOPEX/Poseidon, Jason-1, MODIS Terra/Aqua, QuikSCAT) is suggested. We present the results of the application of the proposed approach to the operational monitoring of seawater condition and pollution in the coastal zone of northeastern Black Sea conducted in 2006. This monitoring is based on daily receiving, processing and analysis of data different in nature (microwave radar images, optical and infrared data), resolution and surface coverage. These data allow us to retrieve information on seawater pollution, sea surface and air-sea boundary layer conditions, seawater temperature and suspended matter distributions, chlorophyll a concentration, mesoscale water dynamics, near-surface wind and surface wave fields. The focus is on coastal seawater circulation mechanisms and their impact on the evolution of pollutants.

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Conditional Signal-Acquisition Parameter Selection for Automated Satellite Laser Ranging System

  • Kim, Simon;Lim, Hyung-Chul;Kim, Byoungsoo
    • Journal of Astronomy and Space Sciences
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    • 제36권2호
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    • pp.97-103
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    • 2019
  • An automated signal-acquisition method for the NASA's space geodesy satellite laser ranging (SGSLR) system is described as a selection of two system parameters with specified probabilities. These parameters are the correlation parameter: the minimum received pulse number for a signal-acquisition and the frame time: the minimum time for the correlation parameter. The probabilities specified are the signal-detection and false-acquisition probabilities to distinguish signals from background noise. The steps of parameter selection are finding the minimum set of values by fitting a curve and performing a graph-domain approximation. However, this selection method is inefficient, not only because of repetition of the entire process if any performance values change, such as the signal and noise count rate, but also because this method is dependent upon system specifications and environmental conditions. Moreover, computation is complicated and graph-domain approximation can introduce inaccuracy. In this study, a new method is proposed to select the parameters via a conditional equation derived from characteristics of the signal-detection and false-acquisition probabilities. The results show that this method yields better efficiency and robustness against changing performance values with simplicity and accuracy and can be easily applied to other satellite laser ranging (SLR) systems.

통계적 특징 기반 SVM을 이용한 야간 전방 차량 검출 기법 (Night Time Leading Vehicle Detection Using Statistical Feature Based SVM)

  • 정정은;김현구;박주현;정호열
    • 대한임베디드공학회논문지
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    • 제7권4호
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    • pp.163-172
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    • 2012
  • A driver assistance system is critical to improve a convenience and stability of vehicle driving. Several systems have been already commercialized such as adaptive cruise control system and forward collision warning system. Efficient vehicle detection is very important to improve such driver assistance systems. Most existing vehicle detection systems are based on a radar system, which measures distance between a host and leading (or oncoming) vehicles under various weather conditions. However, it requires high deployment cost and complexity overload when there are many vehicles. A camera based vehicle detection technique is also good alternative method because of low cost and simple implementation. In general, night time vehicle detection is more complicated than day time vehicle detection, because it is much more difficult to distinguish the vehicle's features such as outline and color under the dim environment. This paper proposes a method to detect vehicles at night time using analysis of a captured color space with reduction of reflection and other light sources in images. Four colors spaces, namely RGB, YCbCr, normalized RGB and Ruta-RGB, are compared each other and evaluated. A suboptimal threshold value is determined by Otsu algorithm and applied to extract candidates of taillights of leading vehicles. Statistical features such as mean, variance, skewness, kurtosis, and entropy are extracted from the candidate regions and used as feature vector for SVM(Support Vector Machine) classifier. According to our simulation results, the proposed statistical feature based SVM provides relatively high performances of leading vehicle detection with various distances in variable nighttime environments.

DEEP-South: Performance of Moving Object Detection Program in Different Observation Modes

  • Oh, Young-Seok;Bae, Yeong-Ho;Kim, Myung-Jin;Roh, Dong-Goo;Jin, Ho;Moon, Hong-Kyu;Park, Jintae;Lee, Hee-Jae;Yim, Hong-Suh;Choi, Young-Jun
    • 천문학회보
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    • 제41권2호
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    • pp.48.3-49
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    • 2016
  • We have five different types of observation modes with regard to the Deep Ecliptic Patrol of the Southern Sky (DEEP-South); Opposition Census (OC) for targeted photometry, Sweet Spot Survey (S1) for discovery and orbit characterization of Atens and Atiras, Ecliptic Survey (S2) for asteroid family studies and comet census, NEOWISE follow-up (NW) for near simultaneous albedo measurements in the visible bands, and Target of Opportunity (TO) observation for follow-up either for unpredictable events or targets of special interests. Different exposures with such different modes result in a wide range of background noise level, the number of background stars and the mover's projected speed in each image. The Moving Object Detection Program (MODP) utilizes multiple mosaic images being taken for the same target fields at different epochs at the three KMTNet sites. MODP employs existing software packages such as SExtractor (Source-Extractor) and SCAMP (Software for Calibrating Astrometry and Photometry); SExtractor generates object catalogs, while SCAMP conducts precision astrometric calibration, then MODP determines if a point source is moving. This package creates animated stamp images for visual inspection with MPC reports, the latter for checking whether an object is known or unknown. We evaluate the astrometric accuracy and efficiency of MODP using the year one dataset obtained from DEEP-South operations.

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LCD표면 검사를 위한 라인스캔 영상의 재구성 (Image Reconstruction Using Line-scan Image for LCD Surface Inspection)

  • 고민석;김우섭;송영철;최두현;박길흠
    • 대한전자공학회논문지SP
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    • 제41권4호
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    • pp.69-74
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    • 2004
  • 본 논문에서는 프로젝션 프로파일(PP: Projection Profile) 과 컬러공간변환(CST: Color Space Transform)을 이용하여 라인스캔 카메라(Line-Scan Camera) 영상을 재구성함으로써 LCD 표면의 결함검출 성능을 높이는 알고리즘을 제안하였다. 제안된 알고리즘은 결함을 포함한 RGB 영역 분할, 대표값 추적시스템을 이용한 대표값 추출, 그리고 컬러공간변환을 이용한 Y영상 재구성 방법들로 구성되어 있다. 실험을 통하여 제안한 방법으로 재구성된 영상의 결함검출 성능이 영역카메라(Aerial Camera)의 결함검출 성능보다 우수함을 보였다.

전기탐사의 지하터널 조사를 위한 역산에 관한 연구 (Inversion of Electrical Prospecting Data for Underground Tunnel Detection)

  • 서백수;고광범
    • 산업기술연구
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    • 제18권
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    • pp.125-130
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    • 1998
  • The undergound space is widely developed because of dometic industry and protection of enviornment. The existence and exact location of tunnel is very important for stability of the enormous underground storage house or building. Various types of prospecting methods have been applied to detection of underground tunnel. In this study, electrical prospecting method is applied to detect tunnel because the development of underground space is very connected with groundwater. Sensitivity analysis is introduced for the calculation of elctrical inversion data. The governing equation is Fourier transformed into the 2-dimensional wave number space and solved by using the finite element method.

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A Study on the MCP Detection System for FIMS

  • Rhee, J.G.;Nam, U.W.;Chun, H.;Min, K.W.;Edelstein, J.;Jin, H.;Korpela, E.
    • 한국우주과학회:학술대회논문집(한국우주과학회보)
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    • 한국우주과학회 1999년도 한국우주과학회보 제8권2호
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    • pp.114-114
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    • 1999
  • No Abstract, See Full Text

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Detection of $H_2$ Fluorescence in Eridanus Region with FIMS

  • Ryu Kwangsun;Min Kyoungwook;Edelstein Jerry;Han Wonyoung;Shin Jongho;Lee Daehee;Seon Kwangil;Nam Ukwon;Park Janghyun;Kim Iljung;Korpela Eric
    • 한국우주과학회:학술대회논문집(한국우주과학회보)
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    • 한국우주과학회 2004년도 한국우주과학회보 제13권2호
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    • pp.50-50
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    • 2004
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