• Journal of Korea Multimedia Society
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• v.13 no.5
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• pp.641-650
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• 2010

Color image sensors (CIS) output color images through image sensors and image signal processing. Image sensors that convert light to electrical signal are divided into CMOS image sensor and CCD image sensor according to transferring method of signal charge. In general, a CIS has RGB output signals from tri-stimulus XYZ of the scene through image signal processing. This paper presents an adaptive colorimetric analysis method to obtain chromaticity and luminance using CIS under various environments. An image sensor for the use of colorimeter is characterized based on the CIE standard colorimetric observer. We use the method of least squares to derive a colorimetric characterization matrix between camera RGB output signals and CIE XYZ tristimulus values. We first survey the camera characterization in the standard environment then derive a SGL(shutter-gain-level) function which is relationship between luminance and auto exposure (AE) characteristic of CIS, and read the status of an AWB(auto white balance) function. Then we can apply CIS to measure luminance and chromaticity from camera outputs and AE resister values without any preprocessing. Camera RGB outputs, register values, and camera photoelectric characteristic are used to analyze the colorimetric results for real scenes such as chromaticity and luminance. Experimental results show that the proposed method is valid in the measuring performance. The proposed method can apply to various fields like surveillant systems of the display or security systems.

• Journal of Nutrition and Health
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• v.15 no.1
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• pp.9-14
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• 1982

The present paper describes a colorimetric method of determining the free and total unsaturated fatty acids in animal tissues. The procedure is based in three steps on the following principles : First step is that the tissue homogenates are extracted in chilled acetone in order to eliminate the interfering substance, such as phospholipids, sulfatides and proteins. At next step, after centrifugation acetone layer is decanted and evaporated to dryness. Then the extract is shaken with heptane to solve in the solvent. That the characteristic nature of copper salts of unsaturated fatty acids are freely soluble in heptane and those of saturated acids are not is the bases of separating one from another. Thus unsaturated fatty acids can be isolated in heptane as their salts from saturated acids and other lipid mixture by shaking with copper reagent. Finally the yellowish brown color developed by adding color reagent (0.2% sodium diethyldithiocarbamate in n-butanol solution) which reacts with the copper salts of the acids and produces the color is measured colorimetrically.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.35S no.9
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• pp.70-77
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• 1998

A new method is proposed for the design of the dichroic mirrors in 3-LCD projection systems for color separation/composition. Rather than simply basing the color performance criterion on luminance or chromatic saturation only, the optimum design parameters can be found by maximizing the perceived color gamut in a 3-D uniform color space. In this method, the half-power wavelengths were optimized by maximizing the volume of the reproducible color gamut in a CIELUV uniform color space for 2 typical viewing conditions, with proper colorimetric analysis of color reproduction in 3-LCD projection systems.

• Journal of the Korean Graphic Arts Communication Society
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• v.24 no.1
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• pp.45-57
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• 2006

Offset lithography is the most widely used printing process in domestic printing industry, but there are no industry-wide specifications for press control to assure consistent quality across printing plants. As printing becomes more of a commodity and less of an art, it is necessary to develop a print quality specification standard suitable for Korea offset printing field. This study aims to contribute to improving the quality of domestic offset color prints by comparative study on color reproduction properties of 2 kinds of domestic process color ink composed of C(cyan), M(magenta), Y(yellow) and K(black) and of 3 kinds of domestic coated paper, using colorimetric color measurement method.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.10
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• pp.1394-1397
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• 2020

The urine test used as a basic test method of in vitro diagnosis for health care has been used for a long time to be simple and convenient. The urine test method is using a color that appears depending on the change in the ion concentration that reacts over time buried in the standard color test paper(Strips) with a urine sample applied to some reaction reagents. In this paper, it was proposed a neural network algorithm to obtain a suitable and reproducibility and accuracy classifier suitable for the urine analysis system. The experimental results were compared with the visual colorimetric analysis, and the neural network algorithm showed better results.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2004.11a
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• pp.306-307
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• 2004

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2004.11a
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• pp.308-309
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• 2004

• Korean Chemical Engineering Research
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• v.49 no.3
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• pp.348-351
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• 2011

In this research, we developed a sensor system which can easily detect several chelating agents using polydiacetylene(PDA) vesicles. In comparison to other sensors, PDA based sensor has several advantages. First, detection method is much simpler and faster because it does not require any labeling step in the experiment procedure. Second, significant color-transition from blue to red based upon external stimulus allows us the detection by naked eyes. Finally, it is also possible to perform quantitative analysis of the concentration of the chelating agent by measuring the colorimetric response. In this paper, five types of chelating agents were used, including EDTA, EGTA, NTA, DCTA and DTPA. Among them, EDTA and DCTA triggered especially strong color-transition. In conclusion, this study has led to a successful development of a color transition-based PDA sensor system for easy and rapid detection of chelating agents.

• Journal of Microbiology and Biotechnology
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• v.31 no.4
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• pp.501-509
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• 2021

More than half the world's population is thought to be infected with Helicobacter pylori. Although the majority of infected people are asymptomatic, H. pylori infection may cause gastric ulcers and deadly gastric cancer. Owing to the difficulty and invasiveness of current routine culture and diagnostic methods, a highly sensitive and specific noninvasive assay for H. pylori is of interest. This study highlighted the design and performance of a colorimetric magneto loop-mediated isothermal amplification (CM-LAMP) assay to detect H. pylori in spiked saliva samples. LF primers were coated on magnetic nanoparticles by carbodiimide-induced immobilization and functionally used for solid-phase amplification. During the LAMP reaction at 66℃, biotin-tagged FIPs were incorporated into LAMP amplicons. The colorimetric signal developed after the addition of NeutrAvidin horseradish peroxidase conjugate (NA-HRP) and ABTS. None of the tested microorganisms, including closely related bacteria, was shown positive by the CM-LAMP assay except H. pylori isolates. This novel platform was highly specific and 100-fold more sensitive (40 CFU/ml or 0.2 CFU per reaction) than the PCR and conventional LAMP assays for the detection of H. pylori in spiked saliva. Our results demonstrated the feasibility of using this noninvasive molecular diagnostic test to detect H. pylori in saliva samples.

• Journal of the Korean Chemical Society
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• v.65 no.4
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• pp.260-267
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• 2021

Increasing the needs for eco-friendly natural materials, much attention on natural dyes has been attracted. Curcumin, one of abundant natural dyes available in nature, is an eco-friendly molecule found in turmeric. In this study, the colorimetric sensing behavior characteristics of ammonia and hydrogen chloride gases was analyzed using curcumin ink-printed paper and cotton fabric by inkjet printing method. The fabricated paper and fabric were utilized as a colorimetric sensor that can track food spoilage. The color changes of the samples printed on the paper and cotton upon exposure to the toxic gases, the reversibility of the color changes, and the water resistance were investigated. Both samples showed reversible reactions with NH3 and HCl, and small amount of ammonia produced by food spoilage was successfully sensed with naked eyes, confirming its capability to warn food spoilage in our daily life.