• 제목/요약/키워드: image uniformity

검색결과 262건 처리시간 0.03초

ASIC Design Controlling Brightness Compensation for Full Color LED Vision

  • Lee Jong Ha;Choi Kyu Hoon;Hwang Sang Moon
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2004년도 학술대회지
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    • pp.836-841
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    • 2004
  • This paper describes ASIC design for brightness revision control, A LED Pixel Matrix (LPM) design and LPM in natural color LED vision. A designed chip has 256 levels of gradation correspond to each Red, Green, Blue LED pixel respectively, which have received 8bit image data. In order to maintain color uniformity by reducing the original rank error of LED, we adjusted the specific character value 'a' and brightness revision value 'b' to pixel unit, module unit and LED vision respectively by brightness characteristic function with 'Y=aX+b'. In this paper, if designed custom chip and brightness revision control method are applied to manufacturing of natural color LED vision, we can obtain good quality of image. Furthermore, it may decrease the cost for manufacturing LED vision or installing the plants.

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Evaluation of Selective Saturation and Refocousing Pulses in Chemical Shift NMR Imaging

  • Shin, Yong-Jin;Park, Young-Sik
    • 한국자기공명학회논문지
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    • 제4권1호
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    • pp.64-73
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    • 2000
  • There are several methods to achieve selective NMR image of differing chemical species with the three most popular methods of Dixon's, CHESS, and SECSI. A major problem common to all chemical shift imaging methods is the uniformity of the static magnetic field and distortions introduced when RF coils are loaded with a conducting specimen. Without magnetic field shimming, these methods cannot be used to acquire selectively image protons in fat and water which are separated by approximately 3.0ppm. Experiments with a phantom, with linewidths of 2.5 to 3.5ppm, were quantitatively evaluated for the three methods and a new chemical shift imaging method. In this study the new chemical shift imaging method (modified CHESS+SECSI technique) which included a selective saturation and refocusing pulse, was developed to determine the ratios of water and fat in different samples.

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Characterization of nano-fiber web structures using a morphological image processing

  • Kim, Jooyong;Lee, Jung-Hae
    • 한국섬유공학회:학술대회논문집
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    • 한국섬유공학회 2003년도 The Korea-Japan Joint Symposium
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    • pp.100-100
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    • 2003
  • An image processing algorithm has been developed in order to analyze the nanofiber web images obtained from a high magnification microscope. It has been known that precise pore detection on thick webs is extremely difficult mainly due to lack of light uniformity, difficulty of fine focusing and translucency of nanofiber web. The pore detection algorithm developed has been found to show excellent performance in characterizing the porous structure, thus being a promising tool for on-line quality control system under mass production. Since the images obtained from an optical microscope represent only web surface, a scale factor has been introduced to estimate the web structure as a whole. Resulting web structures have been compared to those by mercury porosimetry, especially in pore size distribution. It has been shown that those two structures have a strong correlation, indicating that scaling of a single layer web structure can be an effective way of estimating the structure of thick fiber webs.

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KOMPSAT-2 검보정을 위한 MSC Pan에 대한 NUC 적용과 결과 분석 (Applications of MSC Pan Nuc for RAdiometric Cal/Val of KOMPSAT-2)

  • 송정헌;서두천;이동한;임효숙
    • 항공우주기술
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    • 제6권1호
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    • pp.209-212
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    • 2007
  • 복사 보정에 해당하는 NUC(Non-Uniformity Correction)은 MSC 각각의 픽셀들이 가지는 상이한 특성을 균일한 이미지를 얻기 위해 수행하는 작업이다. KOMPSAT-2의 MSC는 각 CCD pixel 별, 각 band 별 특성, 감도 및 시간에 따른 변화, CCD Geometry 등에 의해 왜곡 현상이 일어나게 된다. 검보정 과정에서는 위성 발사 전에 실험실에서의 충분한 실험과 Calibration 작업을 통해 얻어진 값들을 사용하여 Image Restoration, 상대 복사 보정, 절대 복사 보정 등의 작업들을 거쳐서 왜곡 현상을 보정하게 된다. 본 논문에서는 KOMPSAT-2의 NUC(HF NUC & LF NUC) 알고리즘을 이용하여 Panchromatic 밴드의 raw image의 NUC 보정작업 과정과 그 결과에 대해서 소개하고자 한다.

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중적외선 영상 잡음 감소를 위한 SW 필터의 설계 및 구현 (Design and Software Implementation of Noise Reduction Filter for Mid-wave Infrared Images)

  • 박현성;김정호;이성호
    • 한국군사과학기술학회지
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    • 제19권4호
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    • pp.500-507
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    • 2016
  • In order to increase the survivability of combatant ship, measuring and analyzing the infrared radiation is important. Consequently, providing analysis report is also important for the progress of the new combatant ship design. This paper proposes a design and software implementation of filtering for the noise reduction of mid-wave IR camera image. We reduced the total test cost by using the suggested software filtering technique instead of hardware replacement or re-calibration. In addition, we enhanced the accuracy of analysis results by adjusting the parameters of software filtering according to the results of filtered image.

전구용 필라멘트의 제조 공정 해석 및 품질 검사 (Analysis of Coiling Process and Quality Inspection of Filaments for Bulbs)

  • 정태은;표성배;전병희;장병수;김학준
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2000년도 추계학술대회 논문집
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    • pp.771-774
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    • 2000
  • Coiling processes of filaments need precise work and standardization. It is important to maintain equal pitch of filaments. Uniform pitch of filaments is one of the dominant elements of life time and efficiency of bulbs. First coiling process of filament wires is modeled by nonlinear contact problem between filaments and mandrel. Analysis of coiling process using finite element method is conducted to consider manufacturing parameters and pitch distance is calculated under the given conditions. Also image detecting system is developed to inspect uniformity of pitch. This system will be used to inspect quality of filaments during coiling processes.

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CCD를 이용한 미세렌즈의 MTF 측정 (CCD Scanning type MTF Measuring System for Microlens Arrays)

  • 이윤우;조현모;이인원;박태호;윤성균;서형원
    • 한국광학회지
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    • 제5권3호
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    • pp.364-371
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    • 1994
  • 미세렌즈 배열의 실시간 분해능 평가를 위하여 CCD를 이용한 MTF 측정장치를 제작하였다. 현미경 대물렌즈로 상을 확대한 후 CCD를 사용하여 직접 광세기 분포함수를 측정하였으며 사용된 CCD의 화소 크기와 간격, 그리고 감도의 균질성 등을 고려하여 측정한 MTF를 보정하였다. 마이크로 컴퓨터를 사용하여 측정자동화 하였으며 자세한 보정방법과 측정장치에 대하여 설명하였다.

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Study on the First On-Orbit Solar Calibration Measurement of Ocean Scanning Multi-spectral Imager (OSMI)

  • Cho, Young-Min
    • Journal of the Optical Society of Korea
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    • 제5권1호
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    • pp.9-15
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    • 2001
  • The ocean Scanning Multi-spectral Imager (OSMI) is a payload on the KOrea Multi-Purpose SATellite (KOMPSAT) to perform worldwide ocean color monitoring f the study of biological oceanography. OSMI performs solar and dark calibrations for on-orbit instrument calibration. The purpose of the solar calibration is to monitor the degradation of imaging performance for each pixel of 6 spectral bands and to correct the degradation effect on OSMI image during the ground station date processing. The design, the operation concept, and the radiometric characteristics of the solar calibration are investigated. A linear model of image response and a solar calibration radiance model are proposed to study the instrument characteristics using the solar calibration data. The performance of spectral responsivity and spatial response uniformity. The first solar calibration data and the analysis results are important references for further study on the on-orbit stability of OSMI response during its lifetime.

형광 나노입자를 수용하는 마이크로캡슐의 제작 및 수용 가시화 (Fabrication of Microcapsules Encapsulating Fluorescent Nanoparticles and Visualization of Their Inclusion)

  • 김은영;김형훈;고정상
    • 한국가시화정보학회지
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    • 제9권2호
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    • pp.16-20
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    • 2011
  • This paper presents a fabrication method of microcapsules encapsulating fluorescent nanoparticles sensitive to an organic liquid, which is potentially applicable to the encapsulation of protein, cell and drug. It uses the supra-molecular self-assembly of a block copolymer at the interface of the stable and controllable droplets of water suspended with fluorescent nanoparticles and the polymer solved organic. The size and uniformity of the microcapsules were examined for the various polymer concentrations by using SEM image analysis. The maximum standard deviation of the produced microcapsules of less than 3.5% was obtained from the microcapsules produced from the same conditions. The inclusion of fluorescent nanoparticles was visualized in the fluorescence microscope and by using TEM image. It is shown that this fabrication method can provide the uniform size microcapsules with a higher inclusion.

컨벌루션 함수를 이용한 자동두께측정 영상의 성능분석 (Performance Analysis of Automatic Thickness Image using Convolution Function)

  • 강민구;조문신
    • 인터넷정보학회논문지
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    • 제11권1호
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    • pp.21-26
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    • 2010
  • 본 논문에서는 LCD TV용 필름의 균일성을 개선하고자, 소프트 엑스레이(soft X-ray)를 이용하여 볼트 연결기법과 컨벌루션(convolution) 함수기반의 영상처리를 결합한다. 필름의 프로파일에서 두께를 측정하는 라인 스캔과정에서 선원 변경 시 오프셋 오류가 발생한다. 이러한 선원의 오프셋 오류를 제거하고자, 인접한 3개 볼트의 영상에 대해 컨벌루션 함수를 적용함으로써 자동으로 두께 측정이 가능하고, 영상분석 성능을 향상한다.