• 제목/요약/키워드: spectral

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멀티스펙트럼 영상 획득 시스템 구현 (Implementation of Multispectral Imaging System)

  • 진윤종;이문현;노성규;박종일
    • 한국HCI학회:학술대회논문집
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    • 한국HCI학회 2008년도 학술대회 1부
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    • pp.717-721
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    • 2008
  • 본 논문에서는 RGB 카메라와 LED 광원만을 이용하여 객체에 대한 반사 스펙트럼을 효율적으로 측정하는 영상 획득 시스템을 제안한다. 멀티스펙트럼 영상 획득 시스템은 LED 컨트롤러, LED 클러스터, RGB 카메라로 구성되고 전역 스펙트럼(full spectrum)의 영상을 실시간으로 획득하는 시스템이다. 제안된 시스템은 스펙트럼 기저 함수들의 선형 결함으로 전역 스펙트럼을 재구성하여 비교적 간단하면서도 높은 정확도를 보장해준다. 본 시스템의 효용성을 증명하기 위해 다양한 장면(scene)에 대한 반사 스펙트럼을 측정하고 이를 이용하여 여러 광원을 적용한 재조명 결과를 보여준다.

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The Relation between the Spectral Lag and the Collimation-Corrected Luminosity in Gamma-Ray Bursts

  • Jo, Yun-A;Chang, Heon-Young
    • 천문학회보
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    • 제40권2호
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    • pp.51.3-52
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    • 2015
  • Gamma-Ray Bursts(GRBs) are the most violent event in the universe, whose detection rate is a few in a day. The spectral lag, which is commonly observed in the observed light curves of GRBs, is a difference in arrival times of the high-energy and low-energy photons. The relation between the spectral lag and the luminosity of the observed GRBs is shown to be anti-correlated in previous studies. In reported relations to date, the isotropic luminosity has been assumed. On the other hand, GRBs are likely to emit its energy through a beamed jet. In this study, we attempt to obtain the relation between the spectral lag and the collimation-corrected luminosity. We have calculated collimation-corrected luminosities and opening angles using the observed light curves taken from a database of Swift/BAT, XRT. We expect to increase its significance level by expanding a sample size compared with those previously analyzed.

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Hyperion 영상의 제약선형분광혼합분석 기반 무감독 Endmember 추출 최적화 기법 (Unsupervised Endmember Selection Optimization Process based on Constrained Linear Spectral Unmixing of Hyperion Image)

  • 최재완;김용일;유기윤
    • 한국측량학회:학술대회논문집
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    • 한국측량학회 2006년도 춘계학술발표회 논문집
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    • pp.211-216
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    • 2006
  • The Constrained Linear Spectral Unmixing(CLSU) is investigated for sub-pixel image processing, Its result is the abundance map which mean fractions of endmember existing in a mixed pixel. Compared to the Linear Spectral Unmixing using least square method, CLSU uses the NNLS (Non-Negative Least Square) algorithm to guarantee that the estimated fractions are constrained. But, CLSU gets Into difficulty in image processing due to select endmember at a user's disposition. In this study, endmember selection optimization method using entropy in the error-image analysis is proposed. In experiments which is used hyperion image, it is shown that our method can select endmember number than CLSU based on unsupervised endemeber selection.

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SPECTRAL DUALITIES OF MV-ALGEBRAS

  • Choe, Tae-Ho;Kim, Eun-Sup;Park, Young-Soo
    • 대한수학회지
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    • 제42권6호
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    • pp.1111-1120
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    • 2005
  • Hong and Nel in [8] obtained a number of spectral dualities between a cartesian closed topological category X and a category of algebras of suitable type in X in accordance with the original formalism of Porst and Wischnewsky[12]. In this paper, there arises a dual adjointness S $\vdash$ C between the category X = Lim of limit spaces and that A of MV-algebras in X. We firstly show that the spectral duality: $S(A)^{op}{\simeq}C(X^{op})$ holds for the dualizing object K = I = [0,1] or K = 2 = {0, 1}. Secondly, we study a duality between the category of Tychonoff spaces and the category of semi-simple MV-algebras. Furthermore, it is shown that for any $X\;\in\;Lim\;(X\;{\neq}\;{\emptyset})\;C(X,\;I)$ is densely embedded into a cube $I^/H/$, where H is a set.

경부고속도로와 88고속도로에 대한 트럭수송시의 진동 특성 측정 및 분석 연구 (Measurements and Analysis of Truck Transport Vibration Characteristics on the Gyungbu and 88 Highway)

  • 박인식
    • 한국포장학회지
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    • 제12권1호
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    • pp.21-25
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    • 2006
  • Measurements of accelerometer levels transmitted from the floor in commercials truck shipments were carried out transportation of 300 Kg-load from Gyungbu Highway(Waegouan-Seoul) to 88 Highway(Gwangju-Daegu). Different characteristics were observed the values measured the vibration levels with directions in the two Highway's as a function of road condition and truck speed. The results showed that the vibration levels of the Gyungbu Highway is much higher than those of the 88 Highway. A following analysis on the obtained values was used to get the acceleration spectral density (ASD) and power spectral density (PSD). For the entire transit route, the results showed that the level of vibration to vertical direction was significant effects for damaging the products carried compared to other directions such as longitudinal and transverse. This paper provides an updated history of measured characteristics of vibration levels for highways using mainly in domestic area.

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DEM interpolation using spectral information

  • Ji, Jun
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 1999년도 Proceedings of International Symposium on Remote Sensing
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    • pp.299-302
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    • 1999
  • Generation of a Digital Elevation Model (DEM) in remote sensing is an important application. The process of DEM generation often requires interpolation. This paper is aimed to introduce a class of interpolation algorithms using spectral information, which is widely used in geophysical applications, and to examine the applicability of the method to DEM interpolation. The interpolation process can be explained in two steps. The first step is for finding spectral information from the known data and the second step is finding missing data so as to follow the spectral trend found in the previous step. The interpolation algorithm has been tested for a real DEM data and problems in the DEM interpolation are discussed.

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Test Application of KOMPSAT-2 to the Detection of Microphytobenthos in Tidal Flats

  • Won Joong-Sun;Lee Yoon-Kyung;Choi Jaewon
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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    • pp.249-252
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    • 2005
  • Microphytobenthos bloom from late January to early March in Korean tidal flats. KOMPSAT-2 will provide multi-spectral images with a spatial resolution of 4 m comparable with IKONOS. Using IKONOS and Landsat data, algal mat detection was tested in the Saemangeum area~ Micro-benthic diatoms are abundant and a major primary product in the tidal flats. A linear spectral unmixing (LSU) method was applied to the test data. LSU was effective to detect algal mat and the classified algal mat fraction well correlated with NDVI image. Fine grained upper tidal flats are generally known to be the best environment for algal mat. Algal mat thriving in coarse grained lower tidal flats as well as upper tidal flats were reported in this study. A high resolution multi-spectral sensor in KOMPSAT-2 will provide useful data for long-term monitoring of microphytobenthos in tidal flats.

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비정질 실리콘 박막 트랜지스터의 광누설 전류와 다양한 광원의 광자 에너지스펙트럼과의 관계에 관한 연구 (A Study on the Relationship between Photo Leakage Current of a-Si:H Thin Film Transistor and the Photon Energy Spectrum of various Backlight Sources)

  • 정경서;권상직;조의식
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2009년도 춘계학술대회 논문집
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    • pp.70-71
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    • 2009
  • Photoelectric characteristics of a hydrogenated amorphous silicon thin film transistor(a-Si:H TFT) were obtained for the illumination from various backlight sources and the results were compared and analyzed in terms of the photon energy spectral characteristics of the backlights obtained from the integration of the multiplication of the photon energy and the spectral intensity at etch wavelength. It was possible to conclude that the absorption of illuminated backlight to a-Si:H layer and the generation of electrons and holes are mainly carried out at the wavelength less than 500nm.

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뇌파 상대 스펙트럼의 숙련도 평가 척도로의 이용 가능성에 대한 연구 (A Study on Applicability of EEG Spectral Relative Power as a Measure of Expertise Level)

  • 옥동민;박희석
    • 대한인간공학회지
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    • 제29권5호
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    • pp.741-750
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    • 2010
  • The objective of this paper is to study if the EEG spectral relative power would be a reasonable measure of expertise level. EEG electrodes were placed on the locations of Fp1, Fp2, F3, F4, T3, T4, O1, O2 while 5 subjects were playing 4 kinds of game on PC. EEG spectral relative power was significantly related with expertise level on the locations of Fp1, T3, T4, O1, O2. And the results showed that the $\theta$ and $\alpha$ activities were decreased, while $\beta$ and $\gamma$ activities were increased. The results indicated that the EEG spectral relative power would be applicable as a quantitative measure of expertise level.

비정질 실리콘 박막 트랜지스터의 광특성 분석을 위한 백라이트의 광자 에너지 스펙트럼에 대한 연구 (A Study on the Photon Energy Spectrums of Backlight for the Analysis of the Photoelectric Characteristics of a-Si:H TFT)

  • 정경서;권상직;조의식
    • 한국전기전자재료학회논문지
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    • 제22권12호
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    • pp.1058-1062
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    • 2009
  • For the investigation of the mechanism of photoelectric characteristics of a hydrogenated amorphous silicon thin film transistor(a-Si:H TFT), spectral characteristics of various backlights were analyzed in terms of the photon energy at each wavelength. Photon energy spectral characteristics were obtained through the multiplication of each photon energy and spectral intensities of backlights at each wavelength and the total photon energies were obtained by the integration of the photon energy spectrums. From the comparison of the experimental photo leakage current and the calculated photon energy, it was possible to conclude that the absorption of illuminated backlight to a-Si:H layer and the generation of electrons and holes are mainly carried out at the wavelength less than 500 nm as described in previous reports.