• 대한임베디드공학회논문지
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• 제8권2호
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• pp.111-119
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• 2013

This paper proposes one method on photometric stereo calibration using the constraint on light source directions in which the light sources have the unknown tilt and slant angles but the slant angles are the same. First, the constraint is analyzed based on the equation of linear ambiguity which leads to the conclusion that another constraint should be added to solve the calibration completely. Later, the combination of constraint on light source directions and the constraint that there exists at least six surface patches having known albedos is exploited to resolve the linear ambiguity up to an accurate and close-form solution. The effective performance of the proposed method is demonstrated through experiment results.

• 천문학회지
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• 제20권2호
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• pp.63-94
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• 1987

Using many homogeneous data of DDO and UBV colors for all luminosity classes and physical quantities known from spectroscopic observations, new calibration schemes with DDO photometric parameters are presented for metal abundance, effective temperature and surface gravity of stars. And an intrinsic color relation is derived for the reddening estimate.

• 센서학회지
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• 제21권2호
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• pp.96-102
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• 2012

This paper addresses photometric distortion problems of a compact 3D scanning sensor which is composed of a micro-size and inexpensive camera-projector system. Recently, many micro-size cameras and projectors are available. However, erroneous 3D scanning results may arise due to the poor and nonlinear photometric properties of the sensors. This paper solves two inherent photometric distortions of the sensors. First, the response functions of both the camera and projector are derived from the least squares solutions of passive and active calibration, respectively. Second, vignetting correction of the vision camera is done by using a conventional method, however the projector vignetting is corrected by using the planar homography between the image planes of the projector and camera, respectively. Experimental results show that the proposed technique enhances the linear properties of the phase patterns that are generated by the sensor.

• 천문학회지
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• 제10권1호
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• pp.31-38
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• 1977

To reduce the instrumental and calibration errors in the photoelectric photometry as much as possible it is necessary to select the optimum photocell voltage and energy attenaution and to observe as many standard stars as possible over the wide range of color, spectral type and air mass.

• 천문학회보
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• 제5권
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• pp.21.2-21.2
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• 1980

• 천문학회보
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• 제45권1호
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• pp.66.4-67
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• 2020

Gyeonggi science high school for the gifted (GSHS) installed 60cm telescope, which is waiting for student observers. It is essential to understand the characteristics of the photometric system, consisting of telescope, filter, and CCD, to get reliable data. CCD images of SA98 Landolt standard field and M67 were obtained on 19th March 2020. The images of each field were combined by filters, i.e., we ignored the monochromatic atmospheric extinction since the photometric objects themselves are standard stars. 24 standard stars in SA98 field and 12 standard stars in M67 were used to derive the tentative transformation equation between our bv photometric system and Johnson BV photometric system. In this poster, we present the preliminary standardization result for Johnson BV photometric system in GSHS 60cm telescope. The reproductivity is discussed by comparing color coefficients of two fields. We plan to extend this process to Johnsons-Cousins BVRI photometric system and narrow-band filters for flux calibration.

• Archives of Pharmacal Research
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• 제6권2호
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• pp.103-108
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• 1983

Such sulfur-containing drugs as chlorpromazine, sulfonamides and thiazides were determined by gas chromatography with flame photometric detector (FPD) and flame ionization detector (FID). 0.6% QF-1 or 3% SE-30 on Chromosorb WAWDMCS were found suitable for drugs listed above. In the experimental conditions given maximum response the FPD response and the response ratio of FPD increased with the number of sulfur atom per molecule. It was possible to obtain a linear calibration curve from $10^{-9}$ / mole to $2{\times}10^{-8}$ / mole and to analyze variety of sulfur drugs by the calibration curve of one sulfur standard.

• 약학회지
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• 제29권5호
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• pp.227-233
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• 1985

A new method of determination of fatty acid using gas chromatography-flame photometric detector (GC-FPD) is described. Fatty acid was methylthiomethyl-esterified with methylthiomethy chloride in 1,8-diazabicyclo [5,4,0]-undec-7-ene catalyst and its concentration measured by GC-FPD with 3%OV-1 or 3% FS-1 column. The FPD responses of thirteen fatty acid methylthiomethyl esters were examined and were proportional to the concentration of the esters without regard to their chemical structures. Consequently it was possible to determine various fatty acid using one standard calibration curve by GC-FPD. We could rapidly and conveniently determine varous fatty acids using one standard calibration curve by GC-FPD. We could rapidly and conveniently determine 13 fatty acids in Ginseng Radix alba by this method.

• 천문학회보
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• 제4권
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• pp.26.3-27
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• 1979

• 한국지구과학회지
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• 제43권1호
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• pp.1-22
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• 2022

운장산 천문대에 있는 원격 유성 분광 관측 시스템의 설치 및 운영에 대해 자세히 설명한다. 총 3대의 고감도 CCD 카메라가 설치되었으며 2대의 CCD 카메라에는 렌즈 전면에 회절 격자를 부착하였다. 시스템은 2019년 11월에 설치되었고, f/1.2 렌즈와 결합된 고감도의 "Watec-902H2" 카메라가 사용되었다. 스펙트럼 관찰을 위한 회절 격자는 500 l/mm이 사용되었다. 관측은 2019년 11월부터 2020년 6월까지 진행되었다. 유성 탐지 및 후속 분석을 위해 SonotaCo UFO 소프트웨어 제품군을 사용했으며, 유성 스펙트럼을 분석하기 위해서는 RSpec 소프트웨어를 사용하였다. 관측영상을 활용하기 위해 Astronomical Calibration과 Photometric Calibration을 수행하였고, 최종적으로 유성의 화학 성분을 분석하였다. 우리는 유성 분광 관측 시스템의 설치와 설정/운영 경험을 설명하고 첫 번째 관측 결과를 제시한다. 또한 결과를 통해 유성의 기원에 대한 간략한 정보를 제공하고자 한다.