• Korean Journal of Fisheries and Aquatic Sciences
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• v.57 no.3
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• pp.253-261
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• 2024

This study investigated the digital color profiles corresponding to different maturity stages and levels of brown croaker Miichthys miiuy specimens collected from the Southern Sea of South Korea. Maturity stages were determined using photomicrographs of ovarian developmental phases, which were compared with digital color values. Brown croaker specimens ranged from 24 to 81 cm in standard length; mature ovaries were predominantly observed in specimens that exceed 40 cm in length. Monthly ovary color values were primarily concentrated in the 1st and 4th quadrants, with both a^* and b^* values falling within a range of ±15 centered on the origin. Similarly, the testes color values were predominantly situated in the 4th quadrant, with a^* and b^* values ranging from -5 to 15 and 10 to 14, respectively. While the color values of the mature and spawning stages overlapped within a narrow range, distinguishing between them required both the color value and monthly color value distribution to be considered. Thus, this study underscores the efficacy of digital color measurements for assessing brown croaker gonad maturity, and provides more quantitative insights compared to subjective visual assessments by humans.

• Proceedings of the Optical Society of Korea Conference
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• 2007.07a
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• pp.193-194
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• 2007

• Journal of The Korean Astronomical Society
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• v.42 no.6
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• pp.155-159
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• 2009

In order to determine color excess in the $uvby\beta$ color system for high amplitude $\delta$ Scuti stars, reddening free $[m_1]$, $[c_1]$, and $\beta$ indices data were obtained from the existing literature for 21 stars. Then, the three intrinsic relations of $(b-y)_0$ - $[m_1]$, $(b-y)_0$ - $[c_1]$, and $(b-y)_0$ - $\beta$ were investigated. Among these, it was shown that the $(b-y)_0$-$[c_1]$ relation is the most useful. By establishing intrinsic $(b-y)_0$-$[c_1]$ relations for six reddening calibration stars, color excesses of other stars were determined.

• Bulletin of the Korean Chemical Society
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• v.25 no.7
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• pp.1009-1011
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• 2004

In the present work a very simple, sensitive and selective spectrophotometric method for the determination of nitrite in micellar media is described. The method is based on the color reaction of nitrite with p-nitroaniline in the presence of diphenylamine in acid media. In order to remove the extraction step, Triton X-100, a non-ionic surfactant was used as micellar media. The optimum reaction conditions such as acid concentration, reagents concentration and effect of time have been studied and the analytical characteristics of the method such as limit of detection, linear range and molar absorptivity have been obtained. The interference of some anions and cations was also tested. The method was applied to the determination of nitrite in real samples.

• Journal of the Korean Society of Tobacco Science
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• v.2 no.2
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• pp.38-43
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• 1980

The spectrophotometric determination oi reducing sugar in the tobacco leaves was carried out by employing blue tetrazolium chloride as a color developing reagent. The absorption maximum of formazan dye which is the product of the reaction between blue tetrazolium chloride and fructose was shown to be $530^{nm}$. In the fructose concentration range of 0.02mg/ml-0.14mg/ml the calibration curve was well coincided to the law of Beer-Lambert. In order to take a look at the accuracy and/or recovery rate of fructose determination, the standard fructose was added to the tobacco leaves and the concentration of this standard fructose was estimated. A tittle lower concentration of the standard fructose compared with the pure one in solution was observed. However, an excellent analytical recovery was revealed under the -2% of relative error limit. When we carried out the quantitative determination of this reducing sugar by the method of visual read-out (without using the spectrophotometer), the relative error was obtained to be $\pm$10%.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.1
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• pp.49-54
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• 1982

Experiments were carried out to establish physiological maturity determination criteria with reference to visibly easy measurement in barley in 1980 at Suweon. Thirty-three cultivars and lines from 500 crossing blocks were classified into 4 heading groups, and 5 variables; moisture content, discoloration of awn, exsertion, lemma and flag leaf were measured. There were highly negative correlations between heading date and ripening periods (r=-0.656$^{**}$ ), so early heading types had longer ripening periods. Comparing with the variables used for maturity determination, moisture content and discoloration of lemma were most sensitive to development of grain-filling. Those two variables, alone or in combination could be used to screen many genotypes of barley for physiological maturity. In determination of maturity with reference to visibly easy measurement, color of lemma changed stably and was the most useful way and discolor of flag leaf increased the accuracy of determination. The color of lemma at this time was Grayish yellow, and the mean moisture content was about 33 percent in 33 barley cultivars and lines.

• Journal of Astronomy and Space Sciences
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• v.15 no.1
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• pp.91-100
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• 1998

Color indexes and effective temperatures for 25 standard stars have been determined as a pilot project which show a relationship between color index and effective temperature in ultraviolet region. The effective temperature was determined by comparing energy distribution curves derived from the IUE low dispersion spectra with Kurucz atmosphere model. The UV color index was deduced by integrating fluxes in $300{\AA}$ interval of the IUE low disperion spectra. The relation between color index and effective temperature in ultraviolet is similar with that of optical region.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.103-106
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• 2003

Retrieval of ocean color information from Multispectral Camera (MSC) on KOMPSAT-2 was investigated to study and characterize small-scale biophysical features in the coastal oceans. Prior to the derivation of such information from space-acquired ocean color imageries, the atmospheric effects largely from path and the air-sea interface should be removed from the total signal recorded at the top of the atmosphere (T$_{TOA}$). In this study, the 'path-extraction' is introduced and demonstrated on the TM and SeaWiFS imageries of highly turbid coastal waters of Korea. The algorithms for retrieval of ocean color information were explored from the remote reflectance (R$_{rs}$) in the visible wavebands of MSC. The determination of coefficient (R$^{2}$) for log-transformed data [ N = 500] was 0.90. Similarly, the R$^{2}$ value for log-transformed data [ N = 500] was found to be 0.93.

• Journal of Biosystems Engineering
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• v.37 no.5
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• pp.327-334
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• 2012

Purpose: The color changes in red pepper during far infrared drying were studied in order to establish a color change model. Methods: The far infrared drying experiments of red pepper were conducted at two temperature levels of 60, $70^{\circ}C$ and two air velocity levels of 0.6 and 0.8 m/s. The results were compared with the hot-air drying method. The surface color changes parameters of red pepper were measured qualitatively based on L (lightness), a (redness), b (yellowness) and total color changes (${\Delta}E$). The goodness of fit of model was estimated using the coefficient of determination ($R^2$), the root mean square error (RMSE), the mean relative percent error (P) and the reduced chi-square (${\chi}^2$). Results: The results show that an increase in drying temperature and air velocity resulted in a decrease in drying time, the values of L (lightness) and a (redness) decreased with drying time during far infrared drying. The developed model showed higher $R^2$ values and lower RMSE, P and ${\chi}^2$ values. Conclusions: The model in this study could be beneficial to describe the color changes of red pepper by far infrared drying.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.37 no.5
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• pp.64-75
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• 2000

This paper proposes a color sample selection method that produces a uniform distribution in the display gamut plus a color reproduction method for using a uniform color sample In contrast to the conventional method, the proposed uniform color samples are selected m CIELAB, a device-independent color space, instead of RGB (red, green, and yellow) or CMY (cyan, magenta, and yellow) space, device-dependent color spaces To evaluate the performance of the proposed color samples, they were applied to color space conversion using both a regression model and neural network As a result, in the case of a color sample of the same size, the color space conversion method using the proposed samples showed a lower color difference for color conversions using either neural or regression.