• Journal of Advanced Marine Engineering and Technology
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• v.23 no.3
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• pp.300-310
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• 1999

A constant-volume combustion chamber is developed to measure the burnt gas temperature over the wide ranges of equivalence ratio from 1.5 to 2.7 and pressure from 0.1 to 2.7 and pressure from 0.1 to 6 MPa by two-color method. The combustion temperature is also calculated by the conventional two-region model. The premixed fuel rich propane-oxygen-inert gas mixtures under high pressures are simultaneously ignited by eight spark plugs located on the circumference of combustion chamber with 45 degree intervals. The eight converging flames compress the end gases to high pressures. The transmissiv-ity in the chamber center during the final stage of combustion at the highest pressure is measured by in situ laser extinction method. Comparisons are made with the combustion temperatures between two-color method and two-region model. It is found that the burnt gas temperature mea-sured by two-color method is higher than that calculated by two-region model because of being the negative temperature gradient on the calculation and the temperature distribution of light path-length on the measurement and the burnt gas temperature for the turbulent combustion is higher than that of the laminar combustion under the same conditions because the heat loss for turbulent combustion is lower due to the shorter combustion period.

• Journal of the Korean Society of Clothing and Textiles
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• v.44 no.1
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• pp.68-83
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• 2020

This study suggests a method to predict the color appearance of textiles that shifts depending on illumination variations. The suggested method allows the calculations of lightness, chroma, and hue appearance values from the spectral reflectance values of the textile and illuminant. The accuracy of the method was evaluated through numerical and statistical comparisons between the predicted and the measured color appearance values of 24 fabric samples under CIE standard illuminant D65. As a result, there were excellent agreements between the two data sets with the error values close to zero. The predicted color appearance values of 24 samples under two illuminating (color temperature-luminance) conditions, 2700 K-100 cd/㎡ and 6500 K-100 cd/㎡, were then compared to prove the significant effect of illumination on the color appearance of textiles. The color appearance values were also compared with spectrophotometrically measured physical color attributes, that is, true colors of the samples. The physical color attributes of samples were unchanged; however, differences in color appearance under different conditions were generally much larger than the suprathreshold color difference tolerances discussed in the color science literature. Finally, the magnitude of the illumination effect depending on the physical color attributes of samples was also analyzed.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.01a
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• pp.396-399
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• 2009

In this paper, we present a method to define a color similarity between color images using Octree-based quantization and similar color integration. The proposed method defines major colors from each image using Octree-based quantization. Two color palettes to consist of major colors are compared based on Euclidean distance and similar color bins between palettes are matched. Multiple matched color bins are integrated and major colors are adjusted. Color histogram based on the color palette is constructed for each image and the difference between two histograms is computed by the weighted Euclidean distance between the matched color bins in consideration of the frequency of each bin. As an experiment to validate the usefulness, we discriminated the same clothing from CCD camera images based on the proposed color similarity analysis. We retrieved the same clothing images with the success rate of 88 % using only color analysis without texture analysis.

• Journal of Broadcast Engineering
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• v.14 no.4
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• pp.397-408
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• 2009

In this paper, we present a non-static color histogram method to retrieve clothing images that are similar to a query clothing. Given clothing area, our method automatically extracts major colors by using the octree-based quantization approach[16]. Then, a color palette that is composed of the major colors is generated. The feature of each clothing, which can be either a query or a database clothing image, is represented as a color histogram based on its color palette. We define the match color bins between two possibly different color palettes, and unify the color palettes by merging or deleting some color bins if necessary. The similarity between two histograms is measured by using the weighted Euclidean distance between the match color bins, where the weight is derived from the frequency of each bin. We compare our method with previous histogram matching methods through experiments. Compared to HSV cumulative histogram-based approach, our method improves the retrieval precision by 13.7 % with less number of color bins.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.5
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• pp.60-69
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• 2003

The simplified two-color method is proposed which can estimate the temperature distribution and the soot density of the whole flame with the image analysis of the high-speed photographs. The factors influenced on its processing were examined, for example, the selection of the wave length, the kind of films, the preparation of the calibration curve between the radiance of flame and the luminance temperature. The simplified two-color method reported in this paper can be used as a tool for the improvement of the combustion process in direct injection diesel engine.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.537-539
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• 2008

WOLED devices were fabricated using two complementary color method with two emissive layers of blue and orange color respectively. WOLED's color purity was optimized as changing thickness of blue emissive DPVBi layer with most efficient red emissive layer doped with 0.2% DCJTB in $Alq_3$ and obtained better white color coordinates of (0.36, 0.33) at 9V.

• Proceedings of the Korea Institute of Convergence Signal Processing
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• 2000.12a
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• pp.153-156
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• 2000

Recently, there has been studied on feature extraction method for efficient content-based image retrieval. Especially, Many researchers have been studying on extracting feature from color Information, because of its advantages. This paper proposes a feature and its extraction method based on color correlogram that is extracted from color information in an image. the proposed method is computed from the image segmented into two parts; the complex part and the plain part. Our experiments show that the performance of the proposed method is better as compared with that of the original color correlogram method.

• Journal of the Korean Society of Industry Convergence
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• v.6 no.3
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• pp.247-252
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• 2003

This study is to research on two phase printing method by use of colorants extracted from sappan wood. As for the research, printing effect of printing paste, streaming time, optimal mordant concentration, change of surface color and colorfastness were measured. This experiment showed that modified starch were best on surface color among the modified starch, sodium-alginate, guar gum. And the surface color was best when the steaming time was 60 minutes, mordant concentration 8%(ow.f). And for colorfastness experiment, colorfastness to drycleaning was good, but colorfastness to light and colorfastness to washing showed no desirable result.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.01a
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• pp.124-127
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• 2009

In this paper, we proposed automatically video colorization method with partial color sources in first frame. The input color sources are propagated to other gray pixels with the high correlation between two pixels. To robust again the errors in portion of the weak boundary, we calculate correlation between two pixels using dual-path comparison. Video colorization method should maintain the color connectivity between frames. Accordingly, we define reliability of primarily color by compare the color of neighborhood frames. We perform the color correction by blending neighboring color when the reliability of primarily color is low. We formalize this premise with energy function, and find the color to minimize the energy function. In this way, using property of video, we reduce the error caused by propagation and get result of natural changes between frames. Through simulation results, we show the proposed method derive a natural result more than previous method.

• Agricultural and Biosystems Engineering
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• v.3 no.1
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• pp.35-43
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• 2002

The spectral color resolution of an image is very important in color image analysis. Two factors influencing the spectral color resolution of an image are illumination intensity and lens aperture for a selected vision system. An optimal combination of illumination intensity and lens aperture for color image analysis was determined in the study. The method was based on a model of dynamic range defined as the absolute difference between digital values of selected foreground and background color in the image. The role of illumination intensity in machine vision was also described and a computer program for simulating the optimal combination of two factors was implemented for verifying the related algorithm. It was possible to estimate the non-saturating range of the illumination intensity (input voltage in the study) and the lens aperture by using a model of dynamic range. The method provided an optimal combination of the illumination intensity and the lens aperture, maximizing the color resolution between colors of interest in color analysis, and the estimated color resolution at the combination for a given vision system configuration.