• 전자공학회논문지 IE
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• v.46 no.3
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• pp.12-18
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• 2009

In this paper, we developed white balance correction processor for Full Color LED Display System which could be display uniformity color and soft light by adjusting brightness of red, green, blue pixel, individually. This processor correct brightness by calculating operating current of each pixel(red, green, blue LED) on the basis of characteristic curve of LED device when we named "a" as a specific characteristic value, "b" as a brightness correction value according to using time, "X" as a operating current value, and "Y" as brightness value. As the results, we solved the reduction problem of brightness for long used LED devices, according to increase entire mean of brightness value by adjusting "b" value from the brightness characteristic function.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.325-329
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• 2003

In this paper. the stability and performance analysis of wave-based teleoperation system is presented. For stability and performance analysis with respect to the variation of characteristic impedance b, loop gains of communication channel and minimum value of trasmitted impedance from slave side to the master side are considered. The stability of slave side may be enhanced by increasing characteristic impedance b, whereas exssively high value of b may degrade the performance, which imply a tradeoff between stability and performance.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.1
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• pp.791-801
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• 2021

This study aims to test whether and to what extend national culture affects the readiness of business-to-consumer (B2C) e-commerce across the world. We regress two sets of data at national level: (1) the ratings of two main dimensions of Hofstede's national culture framework, uncertainty avoidance and individualism, and (2) UTCTAD B2C e-commerce index value. A sample of 83 countries was tested in this study. Several control variables at national level are included in our regression model. We find that these two cultural dimensions have an effect on the readiness of B2C e-commerce in various ways. We find that countries with high individualism score have high index value of B2C e-commerce development. We discuss the implications of these findings for B2C e-commerce developing strategies. We then call for designing relative policies with full consideration on national culture to promote the development of B2C e-commerce. In addition, we identify the limitations of the study and propose recommendations for future research. This study is the first one to use UNCTAD data on B2C e-commerce to explore the relationships between two dimensions of Hofstede's national culture and the readiness of B2C e-commerce and adds to the knowledge of literature in this research field.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.2
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• pp.163-170
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• 1992

Color of kimchi juice was measured instrumentally to evaluate the quality of Korean cabbage kimchi during fermentation at 4$^{\circ}C$ and 16$^{\circ}C$ . These results were compared with those of chemical analyses of kimchi juice and sensory evaluation for kimchi. Chemiral analyses and sensory evaluation showed that the kimchi has reached pH 4.3, the pH value under an optimum ripening period, after 3-days fermentation at 16$^{\circ}C$ with almost the highest contents of vitamin C and carotenoids as well as desirable sour taste and texture. At 4$^{\circ}C$ the kimchi was unripened after 6-days fermentation. At 16$^{\circ}C$, $L^{*}$ value of kimchi juice did not show any significant change during fermentation periods. However, $a^{*}$ value increased until day 4$^{\circ}C$ and thereafter decreased sharply. $b^{*}$ value increased until day 3 and then showed no change. High correlations were seen between volume of kimchi juice, pH, total acidity and $L^{*}$or $b^{*}$ value, and between carotenoid content and $a^{*}$ value, respectively. It was desirable to use color $a^{*}$ or $b^{*}$ value of kimchi juice to evaluate the quality of kimchi. The kimchi was under an over-ripening period when $a^{*}$ value was equal to or lower than the initial value, or when $b^{*}$ value was almost constant. Predicting an optimum ripening period was possible by using a proportional value of $a^{*/}$ $b^{*}$ , i.e., unripening period, 1 $\geq$ and near 1 ; optimum ripening period, near 0.8 ; over-ripening period, < 0.8.eriod, < 0.8.d, < 0.8.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.13 no.4
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• pp.14-20
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• 2017

Refrigerant having high global warming potentials will be phased out due to environmental protection issues. R410A has been widely used in geothermal heat pump. However, it has a little high GWP by 2088 value. One of the recommended substitute for R410A refrigerant is R452B which having a GWP by 698 value. In this paper, the heating and cooling performance of the water-to-water geothermal heat pump unit with R452B was experimentally investigated. The performance of the heat pump adopting R452B was also compared with the system applying R410A. The heating and cooling capacity of R452B heat pump system showed a slightly lower values within 2% comparing with R410A system. However, the R452B system's coefficient of performance was enhanced by 5.2% and 13.7% at heating and cooling mode, respectively.

• Journal of Magnetics
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• v.22 no.1
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• pp.146-149
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• 2017

In this study, we compared the standardized value of each signal intensity, the apparent diffusion coefficient (ADC) that digitizes the diffusion of water molecules, and the signal to noise ratio (SNR) using b value 0 400, 1400 ($s/mm^2$). From March 2013 to December 2013, patients with suspicion of simple compound fracture and metastatic spine cancer were included in the MR readout. We used a 1.5 Tesla Achieva MRI system and a Syn-Spine Coil. Sequence is a DWI SE-EPI sagittal (diffusion weighted imaging spin echo-echo planar imaging sagittal) image with b-factor ($s/mm^2$) 0, 400, 1400 were used. Data analysis showed ROI (Region of Interest) in diseased area with high SI (signal intensity) in diffusion-weighted image b value 0 ($s/mm^2$) Using the MRIcro program, each SI was calculated with images of b-value 0, 400, and 1400 ($s/mm^2$), ADC map was obtained using Metlab Software with each image of b-value, The ADC is obtained by applying the ROI to the same position. The standardized values ($SI_{400}/SI_0$, $SI_{400}/SI_0$) of simple compression fractures were $0.47{\pm}0.04$ and $0.23{\pm}0.03$ and the standardized values ($SI_{400}/SI_0$, $SI_{400}/SI_0$) of the metastatic spine were $0.57{\pm}0.07$ and $0.32{\pm}0.08$ And the standardized values of the two diseases were statistically significant (p < 0.05). The ADC ($mm^2/s$) for b value 400 ($s/mm^2$) and 1400 ($s/mm^2$) of the simple compression fracture disease site were $1.70{\pm}0.16$ and $0.93{\pm}0.28$ and $1.24{\pm}0.21$ and $0.80{\pm}0.15$ for the metastatic spine. The ADC ($mm^2/s$) for b value 400($s/mm^2$) was statistically significant (p < 0.05) but the ADC ($mm^2/s$) for b value 1400 (p > 0.05). In conclusion, multi - b value recognition of signal changes in diffusion - weighted imaging is very important for the diagnosis of various spinal diseases.

• Journal of the Korean Society of Clothing and Textiles
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• v.21 no.3
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• pp.524-535
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• 1997

The purpose of this study was to find out the clothing values and meanings by material values. The researcher used the scales of Richins & Dawson (1992) for Materialism Scale. The scales of Prentice (1987) and Ricllins (1994a, 1994b) for privateand public meanings of clothing. The scales of Prentice (1987) and Richins (1994a, 1994b) for importance clothes of private and public meanings.. The scales of Creekmore (1968) for clothing values. The subjects of this study were 154 girl students in the university. The research materials was analyzed by Frequency, MANOVA and Scheffe test The results of this study were as follows; 1) Higher group of material values had an orientation that emphasizes enjoyment values of clothing in private moaning and seems expensive of clothing in public meaning. 2) All group set a high value on both suits and jeans in clothing of private meanie that meant both interpersonal and enjoyment values and put much worth on both suits and mustang that concerned both costly and brand. 3) Higher group had significantly difference in aesthetic value and political value, and lower had significantly differene ineconomic value and theoretical value.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.27 no.1
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• pp.1-7
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• 2016

In this paper, the tunable filter based on high power cavity using mechanical switch for 1.5 GHz band is presented. The LPF is inserted to eliminate the spurious wave, coupler is embeded to extract the output power, and then the tunable filter system is configured using mechanical switch. The LPF obtains attenuation over 40 dB between 4 GHz and 12.75 GHz, Coupler is satisfied with coupling value 40 dB and coupling isolation over 55 dB. The tunable filter system using mechanical switch obtains insertion loss 0.88 dB at bypass mode between 1,495.9 MHz and 1,510. 9 MHz, 3.29 dB at fil mode between 1,495.9 MHz and 1,500.9 MHz. It is also satisfied with output power of 132 W at the center frequency 1,498.4 MHz, and switching time below 10 ms.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.6
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• pp.512-515
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• 2004

The purpose of this experiment was to obtain informations about variation of anthocyanin content within black-seeded soybean testa according to cultivation and harvest time. Three varieties, Ilpumgeomjeongkong, Geomjeongkong 2, Tawonkong were tested in this experiment. Seeds were planted on April 15 (early planting), May 15 (optimum planting), and June 15 (late planting), respectively. Harvest time was R6 (full seed), R7 (physiological maturity), and R8 (harvest maturity), respectively. The content of delphinidin-3-glucoside (D3G), cyanidin-3-glucoside (C3G), petunidin-3-glucoside (Pt3G), and total anthocyanin (TA) had all increased gradually from April 15 to June 15 as well as R6 to R8. There was no varietal difference in D3G, but C3G and TA of Geomjeongkong 2 were higher than other two varieties. Pt3G was the highest Tawonkong of varieties. The value of L as anthocyanin color difference had gradually decreased from April 15 to June 15 and R6 to R8, Geomjeongkong 2 among three varieties was the lowest. The value of a was the highest on May 15 and increased gradually from R6 to R8, Geomjeongkong 2 was the lowest. The value of b was the highest on June 15 as late planting and was the highest Geomjeongkong 2 of varieties. The value of b had increased gradually from R6 to R8. D3G, C3G, Pt3G, and TA contents showed mutually high positive correlation and these four characters were represented high negative correlation with L value but showed high positive correlation with a and b values. The value of L showed high negative correlation with a and b values. The value of a showed high positive correlation with b value.

• Atmosphere
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• v.21 no.1
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• pp.123-130
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• 2011

In this study, we have analyzed the radiative characteristics of erythemal ultraviolet-B (EUV-B from 1999 to 2005) over the Korean Peninsula. EUV-B measured at Gangneung, Anmyondo, Mokpo, and Gosan represents the measurements from clean areas and that at Seoul represents from a polluted area. The magnitudes of EUV-B increase in proportion to the latitudinal decrease. Monthly mean variation of EUV-B at noon shows the maximum value of $158.5mWm^{-2}$ in August and the minimum value of $36.4mWm^{-2}$ in December in the clean areas. Seasonal mean diurnal variation of EUV-B shows a peak around noon (12:00 ~ 13:00 hr) and its intensity varies along with a season in order of summer > spring > fall > winter. The maximum value of $56.4mWm^{-2}$ in summer is three times higher than that in winter ($14.3mWm^{-2}$). The value of EUV-B in the polluted area is lower than that in the clean areas, resulting from the effects of the blocking, reflection, and scattering of EUV-B due to high concentrations of PM10. UV-B is an essential element to synthesize vitamin D in human body. 200 IU(International Unite) of vitamin D can be formed by an exposure of 6-10% of body surface area to 0.5 MED(Minimal Erythemal Dose). In order to form vitamin D, the calculated exposure times to EUV-B are 15 min. in spring, 12 min. in summer, 18 min. in fall, and 37 min. in winter for the clean areas and 16, 16, 24, and 37 min. for the polluted area.