• Title/Summary/Keyword: Color measurement

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3D Particle Image Detection by Using Color Encoded Illumination System

  • Kawahashi M.;Hirahara H.
    • 한국가시화정보학회:학술대회논문집
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    • 2001.12a
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    • pp.100-107
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    • 2001
  • A simple new technique of particle depth position measurement, which can be applied for three-dimensional velocity measurement of fluid flows, is proposed. Two color illumination system that intensity is encoded as a function of z-coordinate is introduced. A calibration procedure is described and a profile of small sphere is detected by using the present method as preliminary test. Then, this method is applied to three-dimensional velocity field measurement of simple flow fields seeded with tracer particles. The motion of the particles is recorded by color 3CCD camera. The particle position in the image plane is read directly from the recorded image and the depth of each particle is measured by calculation of the intensity ratio of encoded two color illumination. Therefore three-dimensional velocity components are reconstructed. Although the result includes to some extent error, the feasibility of the present technique for three-dimensional velocity measurement was confirmed.

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Simultaneous Temperature and Velocity Fields Measurements near the Boiling Point

  • Doh, Deog-Hee;Hwang, Tae-Gyu;Koo, Bon-Young;Kim, Seok-Ro
    • Journal of Advanced Marine Engineering and Technology
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    • v.31 no.5
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    • pp.531-542
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    • 2007
  • Simultaneous measurement technique for temperature and velocity fields near a heated solid body has been constructed. The measurement system consists of a 3-late CCD color camera, a color image grabber, a 1ighting system, a host computer and a software for the whole quantification process. Thermo Chromic Liquid Crystals (TCLC) was used as temperature sensors. A neural network was used to get a calibration curve between the temperature and the color change of the TCLC in order to enhance the dynamic range of temperature measurement. The velocity field measurement was attained by the use of the fray-level images taken for the flow field, and by introducing the cross-correlation technique. The temperature and the velocity fields of the forced and the natural convective flows neat the surface of a cartridge heater were measured simultaneously with the constructed measurement system.

A Study on the Subjective Evaluation of Color Appearance under the Different LED CCT Conditions (색온도별 LED 조명에 의한 색상별 색보임에 대한 주관평가 연구)

  • Kim, Hyun-Sun;Kim, Yu-Sin;Choi, An-Seop
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.25 no.2
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    • pp.43-52
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    • 2011
  • LED lighting may cause different sensation and color appearance due to the different spectral power distributions compared to those of conventional lightings. Particularly, the CCT (Correlated Color Temperature) of LED lighting has a major effect on color appearance so that this study conducted an experiment through a subjective evaluation and luminance measurement for effective color appearance in a space. This study performed a subjective evaluation under the seven different LED CCT conditions, and color appearance was evaluated with major five colors in a customized lighting box. In addition, luminance measurement was conducted for each CCT and color condition to compare the results from a subjective evaluation. The results of this study may help to select a proper LED CCT for specific color conditions.

Analysis of Previous Color Study : Focused on Study Category and Color Preference Study (기존의 색채연구유형과 선호색채연구의 분석)

  • 이명희;김미영
    • Journal of the Korean Society of Costume
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    • v.51 no.3
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    • pp.33-49
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    • 2001
  • The purpose of this study was to analyse the previous color studies. A number of publications and journals were reviewed and analyzed carefully. The results of review and analysis were as follows : There were many different subjects in color studies and they were usually categorized into ten fundamental groups : color preferences, color image/symbol/association of ideas, emotion and colors, image making with colors, colors related with consumers' decision making, traditional colors, semantic color description, color plan of apparel merchandise, influential factors on colors, and color coordination preferences. In general, the color preference studies are conducted most actively, and they are followed by the studies of color image/symbol/association of ideas and traditional colors. In the previous studies on the color preferences, they provided sufficient amount of information on the preferred colors and the preferred apparel colors. however, they lacked in providing appropriate explanation on how these color preferences were related with colors in fashion. Also, there have been no thorough studies that questioned the reliability of measurement methods for obtaining color preference data. The authors also realized that it was extremely difficult to find any related publications on the studies that focus various influential variables on the disagreement between the preferred color and preferred apparel color. Thus, this study directed the future studies to solve the problem discussed above.

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Development of an Illumination Measurement Device for Color Distribution Based on a CIE 1931 XYZ Sensor

  • Son, Do-Ky;Cho, Eun-Byeol;Moon, In-Kyu;Park, You-Sang;Lee, Chung-Ghiu
    • Journal of the Optical Society of Korea
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    • v.15 no.1
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    • pp.44-51
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    • 2011
  • In this paper, an easy-to-use measurement device for illumination distribution is developed. The device consists of a sensor array module, a control module, and a PC interface. The sensor array module incorporates CIE 1931 color sensors and the ARM-based 96 MHz microcontroller in the control module for measurement and data processing. The sensor array module contains 64 color sensors arranged in a $16{\times}4$ array. The sensitivity of the sensor array module can be adjusted depending on the illumination level to be measured. The measurement data and control signals are exchanged via USB 2.0 standard. To demonstrate the performance of the device, the illumination distribution is measured for colors of red, green, and blue and is graphically shown. The device can be used for measurement of the illumination distribution, design and adjustment of LED illumination.

The Measurement of Soot Particle Temperatures Using a Two-Color Pyrometry and Modulated LII Signals (Modulated LII 신호와 이색법을 이용한 매연입자 온도 계측)

  • Nam, Youn-Woo;Lee, Won-Nam
    • 한국연소학회:학술대회논문집
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    • 2006.10a
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    • pp.110-116
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    • 2006
  • A new measurement technique based on a two-color pyrometry and modulated LII signals to measure local soot particle temperatures has been proposed and examined experimentally. The theoretical review suggests that modulated LII signals of soot particles is suitable for a two-color pyrometry as long as the temperature increase due to laser heating remains relatively small. The modulated LII signals from ethylene and propylene diffusion flames were simultaneously measured at 550 and 750 nm by a dual measurement system that consists of optical fibers, PMT and lock-in amps. The local soot particle temperatures of diffusion flames could be obtained using a two-color pyrometry and modulated LII signal based new technique.

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Development of an Infrared Two-color Probe for Particle Cloud Temperature Measurement

  • Alshaikh Mohammed, Mohammed Ali;Kim, Ki Seong
    • Journal of ILASS-Korea
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    • v.20 no.4
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    • pp.230-235
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    • 2015
  • The demands for reliable particle cloud temperature measurement exist in many process industries and scientific researches. Particle cloud temperature measurements depend on radiation thermometry at two or more color bands. In this study, we developed a sensitive, fast response and compact online infrared two-color probe to measure the temperature of a particle cloud in a phase of two field flow (solid-gas). The probe employs a detector contained two InGaAs photodiodes with different spectral responses in the same optical path, which allowed a compact probe design. The probe was designed to suit temperature measurements in harsh environments with the advantage of durability. The developed two-color probe is capable of detecting particle cloud temperature as low as $300^{\circ}C$, under dynamic conditions.

A new color management approach for dye manufacturing process with image processing and intelligent algorithm

  • Kyungwon Jang;Taechon Ahn;Lee, Dongyoon;Yangwoong Yoon;Jinhyun Kang
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.56.2-56
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    • 2002
  • A dye process of textile industry is important part that finally gives required quality to the textile material. To produce a proper dye for the customers, color management that precise color measurement from original color sample and rapid estimation of corresponding color recipe is most essential. In the practical dye manufacturing process, color management falls into two categories. First one is color management with an expert knowledge of colorist, the other one is computer aided way. In the former management way, color management fully depends on colorists' expert without support of the measurement and computational devices. Objective color management is impossible in this way. The...

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Surface Color Measurement Uncertainties

  • Hwang, Jisoo;Jeong, Ki-Lyong
    • Journal of the Optical Society of Korea
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    • v.19 no.6
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    • pp.649-657
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    • 2015
  • We present a surface color measurement including quantities of surface color, methods, and uncertainty evaluation. Based on a relation between spectral reflectance and surface color, we study how an uncertainty of spectral reflectance propagates to surface color. In analyzing the uncertainty propagation, we divide the uncertainty into uncorrelated components, fully correlated components, and correlated components with spectrally varying correlations. As an experimental example, we perform spectro-reflectometric measurements for ceramic color plates. With measured spectral reflectance and its uncertainty evaluation, we determine surface color and analyze uncertainties of the ceramic color plates.

The shape measurement of three-dimensional object by using color-coded information (색정보를 이용한 3차원 형상 측정)

  • Kim J.S.;Song C.K.;Joo B.K.;HONG J.H.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2005.06a
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    • pp.1446-1449
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    • 2005
  • The purpose of this study is the real-time shape measurement of three-dimensional object by using color coded information. The paper relates to non-contact optical measurements of surface profiles or displacements, because of optical measurement systems are advantageous over using mechanical sensing, their relatively high speed and non-destructive capabilities. Therefore is particularly useful for three dimensional sensing which requires high horizontal and vertical resolution of measurements over a wide range thereof. Each a red, blue, green by using a inherence colors of hue value are good point.

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