• Tribology and Lubricants
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• v.24 no.1
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• pp.7-13
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• 2008

In this work, a simple and low cost sensor technique is proposed to test oil color in real time using in-line sensor. It is presented to use a ratio of intensity in red wavelength range to intensities of green and blue wavelength ranges (defined as a 'chromatic ratio') in order to estimate the oil color change. The proposed sensor technique is realized by irradiating a white LED as light source and a RGB color sensor as photoreceiver, and the chromatic ratio of various types of used oils are measured. The results show that chromatic ratio generally reflects chemical deterioration of oil, including oil oxidation and thermal degradation. It is concluded that the proposed sensor could be used for an effective oil monitoring technology.

• KSTLE International Journal
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• v.8 no.1
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• pp.1-6
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• 2007

Chromatic device was developed using light emitting diodes, optic fibers and photodiodes. Chromatic ratio and total contamination parameters based on transmitted light intensity in Red, Green, and Blue wavelengths were used for oil chemical and particulate contamination assessment. Chromatic ratio criterion was found independent of the particulate contamination of oil; but depended on chemical degradation, being more sensitive for synthetic than mineral hydraulic oil. Total contamination index of the sensor depended on both the chemical degradation and particulate contamination of the oil; being most sensitive in blue wavelength, and least in the red. Test results for synthetic hydraulic oils monitored corroborated with results of other tests such as viscosity, total acid number, elemental optical emission spectroscopy, particulate counts and UV-VIS photospectrometry. Chromatic ratio showed a clearer indication of oil degradation, compared to key monitoring parameters such as total acid number, viscosity and particle counts. The results showed that these parameters are effective criteria for the condition monitoring of synthetic hydraulic oils.

• Journal of the Korean Society of Costume
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• v.59 no.4
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• pp.67-81
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• 2009

This study aims to characterize the effect of different combinations of chromatic-achromatic colors and 1:2:3 area-ratio variation of stripe necktie, and gender on the image of male wearer. The experimental materials developed for this study are a set of stimuli and response scales. The stimuli consist of 84 color pictures manipulated with every combination of 12 different colors and 7 different area-ratio. The 7-point scale designed for visual evaluation of image formation included 26 bipolar adjectives. The subjects were 2016 undergraduate students in Gyeongnam, Seoul, Busan, and Daegu areas. The results of this study were as follows. The analyses of images of male wearer in terms of combinations of chromatic-achromatic colors and I :2:3 area-ratio variation of oblique stripe necktie reveal that the concerned factors are of five characteristic dimensions of youth-activity, ability, attractiveness, appeal, and warmness. In addition, it has been found that individual images of male wearer are affected by observer's gender as well as combinations of chromatic-achromatic colors and 1:2:3 area-ratio variation of stripe neckties and that those images vary with every combination of each factor. The study results are highly expected to be used as useful sources in developing necktie designs.

• Science of Emotion and Sensibility
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• v.11 no.3
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• pp.325-338
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• 2008

This study aims to characterize the effect of different combinations of chromatic-achromatic colors and area-ratio of stripe necktie, and gender on the image of male wearer. The experimental materials developed for this study are a set of stimuli and response scales. The stimuli consist of 84 color pictures manipulated with every combination of 12 different colors and 7 different area-ratio. The 7-point scale designed for visual evaluation of image formation included 26 bipolar adjectives. The subjects were 2016 undergraduate students in Gyeongnam, Seoul, Busan, and Daegu areas. The results of this study were as follows.; The analyses of images of male wearer in terms of combinations of chromatic-achromatic colors and area-ratio of oblique stripe necktie reveal that the concerned factors are of five characteristic dimensions of youth-activity, ability, attractiveness, appeal, and warmness. In addition, it has been found that individual images of male wearer are affected by observer's gender as well as combinations of chromatic-achromatic colors and area-ratio of stripe neckties and that those images vary with every combination of each factor. The study results are highly expected to be used as useful sources in developing necktie designs.

• Communications of Mathematical Education
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• v.24 no.4
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• pp.923-937
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• 2010

Explain concretely how to apply some integer ratios in making Eastern and Western notes, and show numerically that the chromatic scale coming from the upholding Pythagoras method in Western and the Sambunsonikbub in Eastern are perfectly equal even if they are far from geographically.

• Korean Journal of Optics and Photonics
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• v.10 no.2
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• pp.169-173
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• 1999

We have experimentally investigated the eye margin characteristics of intensity modulated 10Gb/s NRZ signals in optically amplified systems depending on optical signal-to-noise ratio and chromatic dispersion. For the practical system application, the minimum optical signal-to-noise ratio was 25 dB. We utilized the negative chirped transmitter and a dispersion compensation fiber to compensate the chromatic dispersion in single mode fiber. We found the optimum eye opening and receiver sensitivity in case of the residual dispersion of 0~+935 ps/nm.

• Proceedings of the IEEK Conference
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• 2000.11b
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• pp.309-312
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• 2000

In this paper, The Influence of chromatic fiber dispersion on the transmission distance of MMW(millimeter-wave) link is analyzed and discussed. It is shown that dispersion significantly limits the transmission distance in intensity modulated direct detection and heterodyne links operating in the above 20㎓ frequency region by inducing a carrier to noise penalty on the transmitted signal. We analyze and discuss the influence of dispersion induced CNR(Carrier to Noise Ratio) penalty for direct detection and heterodyne method from simulation.

• Journal of IKEEE
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• v.20 no.1
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• pp.26-30
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• 2016

In this paper, an inter-orthogonal frequency division multiplexing (OFDM) sub-carrier distortion due to fiber chromatic dispersion is investigated. The fiber chromatic dispersion induces phase difference among OFDM sub-carriers, resulting in non-symmetric peak to average power ratio (PAPR) inducing inter-OFDM distortion. Experiments to confirm the fiber dispersion are performed in a direct-detection optical front-haul link. Quadrature phase shift keying (QPSK) encoded OFDM symbols at 25 Gbit/s are transmitted over 100 km fiber and the resulting error vector magnitude (EVM) of 40 % is observed.

• Journal of the Optical Society of Korea
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• v.13 no.1
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• pp.107-111
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• 2009

The properties of the chirped fiber Bragg grating (CFBG) as a chromatic dispersion compensator in differential phase-shift-keyed (DPSK) transmission are analyzed. Comparisons of a performance of a CFBG in between DPSK and On-Off Key (OOK) are shown by simulations using the commercial numerical modeling software, $OptSim^{TM}$. In the simulation, we compared the performance of the CFBG when they were used in the RZ-OOK 40 Gbps and the RZ-DPSK 40 Gbps transmission. The simulation results show the performance of an overall transmission with a CFBG in DPSK is inferior to the case of OOK, although DPSK generally has a 3 dB higher SNR (signal-to-noise ratio) than OOK.

• Journal of the Korean Society of Tobacco Science
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• v.26 no.1
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• pp.35-42
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• 2004

This study was carried out to examinate the effect of aging period on chromatic, chemical and organoleptic characteristics, and to evaluate of optimum aging period for each grade in burley leaf tobacco. The leaf tobaccos were produced in 2000, and threshed, redried and packed in carton box under the current methods. Four grades of processed leaf(A3T, B1T, C1W and D3W) were stored during 24 months (May 10, 2001 to April 31, 2003) in warehouse of Chungju Leaf Tobacco Processing Factory. The leaf tobaccos were sampled at three month intervals for analysis of chromatic, chemical and organoleptic properties. pH values of four grades, and Yellow(b) of A3T and BIT were also significantly decreased during the aging. Filling values, tar, nicotine and CO contents of tobacco smoke, and puff number of cigarettes were not significantly changed during the aging. Positive correlation coefficients were significantly observed between irritation of the calculated attributes from contents of volatile oil components in leaf tobacco and that of the panel sensory attributes. The ratio of maximum change in irritation attribute was larger than that in taste attribute during aging. The calculated irritations of 18～24 months aging for A3T and B1T were significantly lower than zero-aging, while those of C1W and D3W were not significant among aging periods. The panel irritations of 12～15 months aging for four grades were low tendency. The results suggest that decrease of aging period for thin leaf from 21～24 to 12～15 months may be beneficial to save storage cost in burley tobacco.