• Title/Summary/Keyword: 단파장적외선

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A Quantitative Study for Hydrothermal Alteration Zones using Short Wavelength Infrared Spectrometry (단파장적외선 분광분석법을 이용한 열수변질대 정량화 연구)

  • Kim, Yong-Hwi;Choi, Seon-Gyu;Ko, Kwang-Beom;Han, Kyeong-Soo;Koo, Min-Ho
    • Economic and Environmental Geology
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    • v.50 no.1
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    • pp.15-26
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    • 2017
  • Advanced argillic, argillic, and phyllic zones are the most important alteration patterns to predict the hidden ore body during exploration of hydrothermal deposits. We examined the quantitative relationship between the spectral absorption characteristics and the mineral content of the synthetic mixtures such as alunite-kaolinite and illite-kaolinite using short wavelength infrared (SWIR) spectroscopy. In the alunite-kaolinite mixtures, the spectral absorption characteristics of the alunite was highly correlated with the Hull quotient reflectance(0.99) and the kaolinite had the highest correlation with the Gaussian peak(0.92). Illite-kaolinite mixtures are essential for Gaussian deconvolution because of the overlap of absorption region. Illite and kaolinite mixtures indicate the high correlation of 0.93 and 0.98, respectively. The error ranges in the alunite-kaolinite(8%) and illite-kaolinite mixtures(5%) derived from SWIR were smaller than the ones(29% and 26%) obtained from X-ray diffraction(Rietveld) analysis. These results show that SWIR spectroscopic analysis is more reliable than XRD Rietveld analysis in terms of quantification of allowed minerals.

Target Tracking based on Kernelized Correlation Filter Using MWIR and SWIR Sensors (MWIR 및 SWIR 센서를 이용한 커널상관필터기반의 표적추적)

  • Sungu Sun;Yuri Lee;Daekyo Seo
    • Journal of the Korea Institute of Military Science and Technology
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    • v.26 no.1
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    • pp.22-30
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    • 2023
  • When tracking small UAVs and drone targets in cloud clutter environments, MWIR sensors are often unable to track targets continuously. To overcome this problem, the SWIR sensor is mounted on the same gimbal. Target tracking uses sensor information fusion or selectively applies information from each sensor. In this case, parallax correction using the target distance is often used. However, it is difficult to apply the existing method to small UAVs and drone targets because the laser rangefinder's beam divergence angle is small, making it difficult to measure the distance. We propose a tracking method which needs not parallax correction of sensors. In the method, images from MWIR and SWIR sensors are captured simultaneously and a tracking error for gimbal driving is chosen by effectiveness measure. In order to prove the method, tracking performance was demonstrated for UAVs and drone targets in the real sky background using MWIR and SWIR image sensors.

Investigation of USGS Short-Wave Infrared Databases and Comparison with Domestic Cases - Focusing on the Availability for the Mineralogical Analyses and an Application on the Domestic Illite - (USGS 단파장 적외선 데이터베이스 분석 및 국내 사례와 비교: 광물학적 활용도 고찰 및 국내 산출 일라이트로의 적용 사례)

  • Chang Seong Kim;Raeyoon Jeong;Soon-Oh Kim;Ji-man Cha
    • Korean Journal of Mineralogy and Petrology
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    • v.36 no.4
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    • pp.259-271
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    • 2023
  • Since the short-wave infrared spectrum has a significant range of variation depending on the production environment, countries with advanced resource exploration are collecting the spectrum and building a database. Representative organizations include the USGS and CSIRO, and they are currently carrying out a project in China that can synthesize and use a large number of existing data. The USGS library provides a total of 2,457 spectra targeting not only minerals but also various materials that respond to infrared radiation. Among these, there are 1,276 mineral spectra, which are about half of the total. The spectrum title includes information, such as analysis devices (NIC4, BECK, ASDNG, etc.), purity codes (a, b, c, d, u), and measurement methods (AREF, RREF, RTGC, TRAN). Analyzed raw data are provided in ASCII and GIF format. The CSIRO library has a total of 502 spectra, of which the majority, 493, correspond to mineral spectra. The USGS library is a free, publically available resource, while the CSIRO library is bundled with TSG8 or must be purchased separately. Among these, when comparing the eight spectra whose spectral shapes can be analyzed with the spectra of domestic illite, the positions of the absorption peaks are significantly different from those of domestic illite, except for one Japanese illite. Additional research will be needed to determine the causes of such differences, and the domestically relevant databases should be established as well.

미래성장 LED 융합 기술 - LED 농생명 융합 기술의 현황 및 전망

  • Lee, Gyu-Han
    • The Optical Journal
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    • s.145
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    • pp.36-40
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    • 2013
  • LED(light emitting diode)는 반도체의 P-N 접합 다이오드의 일종으로, 순방향으로 전압이 걸릴 때 단파장 광이 방출 되는 현상인 전기발광 효과를 이용한 화합물 반도체 소자의 일종으로 발광 다이오드라고도 한다. LED는 화합물 반도체의 화합물의 종류 및 조성비를 조절하여 적외선, 자외선과 빨강에서 보라에 이르는 모든 가시광선이 구현 가능하고, 소비전력이 기존의 광원에 비해 우수한 특성을 가지고 있어, 일반 조명, 산업용 조명, 전광판, TV의 BLU 등 여러 분야에 걸쳐 다양하게 이용되고 있다.

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