• 한국가구학회지
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• 제26권4호
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• pp.467-473
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• 2015

Natural dyeing is considered to be an alternative to chemical staining in terms of harmful VOC-free and environmentally-friendly ingredient. This study was concerned with an evaluation of color performance of naturally dyed- and painted veneer for cylindrical laminated veneer lumber etc. according to the used condition in terms of existence of light and heat in drying. From the results, the color changes by the color of dyed veneer and the type of paint are likely to be affected by fading condition of light or heat. In the future, long-term outdoor exposure test needs to be additionally followed in order to evaluate durable usability of colored veneers.

• 한국인쇄학회:학술대회논문집
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• 한국인쇄학회 1998년도 추계 논문 발표회 논문집
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• pp.1-6
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• 1998

The object color does not look same under the different light source. It depends on the surface spectral reflectance and the spectral distribution of light source. Therefore we should find the surface spectral reflectance of object color and the spectral distribution of light source for color reproduction. Using Winer estimation, we can reconstruct the spectral reflectance from low dimensional images obtained with a few filters. The kind and the number of filters have the effect on the estimation of the spectral reflectance. Therefore it is important that optimal filters are selected to minimize the error of the result. In this paper, we describe methods to select optimal filters with minimum error between measured and estimated surface spectral reflectance and to estimate surface spectral reflectance of Munsell color from six band images by using Wiener estimation.

• Journal of the Optical Society of Korea
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• 제11권2호
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• pp.67-70
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• 2007

A Wide Color Gamut Backlight system was studied using a three-band white Light-Emitting Diode. A three-band white light-emitting diode (LED) was fabricated using an InGaN-based blue LED chip that emits 445-nm blue peak, and a green phosphor and red phosphor that emit 535-nm green and 621-nm red peak emissions, respectively, when excited by 450-nm blue light. Using for this three-band white LED, wide color gamut backlight unit (BLU) was attained. The luminance of BLU and CIE 1931 chromaticity coordinates was $1,700Cd/m^2$ and (0.337, 0.346). Color filter matching simulations for this configuration show that the three-band white LED backlight can be enhanced by up to 16% over conventional white LED backlight color gamut.

• 한국염색가공학회지
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• 제16권6호
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• pp.23-29
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• 2004

The purpose of this study is to improve the dyeability and the color fastness to light of cotton fabric dyed with extraction of cinnamon cassia. Cotton fabric was pretreated with chito-colla to enhance the dyeability, and K/S values were compared chito-colla pretreated fabric and untreated fabric. In addition, to improve of color fastness to light of dyed fabric, it was used FFC compound as mordant. Also, it was measured SOD-liked activity of FFC compound and lifht fastness of dyed fabrics. The results are as follow; K/S value of cotton fabric pretreated with chito-colla(5%) was much more increased than untreated fabric. SOD-liked activity of FFC compound was observed over 70%. Light fastness of cotton fabric treated with FFC compound was 3～4 grades.

• 한국식품저장유통학회지
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• 제14권4호
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• pp.400-407
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• 2007

본 연구는 진열중 조도 처리에 따른 재래종 돈육과 개량종 돈육의 지방산화 및 육색 안정성을 비교하고자 실시하였다. 평균 출하체중 66 kg의 재래종 돼지(거세돈) 5두와 112 kg인 개량종 돼지($Landrace{\times}Yorkshire{\times}Duroc$, 거세돈) 5두를 도축하여 등심(M. longissimus) 부위를 $1^{\circ}C$에서 5일 동안 숙성한 다음 $4^{\circ}C$의 암실 및 3,000 lux에 7일 동안 진열하였다. 재래종이 개량종보다 높은 지방 함량을 가진 반면(p<0.05), 개량종보다 낮은 $C_{14:0},\;C_{18:3},\;C_{20:5}$ 함량을 가졌다(p<0.05). pH는 진열기간 동안 재래종이 개량종보다 낮았으며(p<0.05), 조도 처리시 두 돈육의 PH가 빨리 증가하였다. TBARS는 재래종이 진열기간 동안 개량종보다 빨리 촉진되었으며, 조도 처리시 더 빨리 증가하였다. 표면육색은 조도 처리시 두 돈육 모두 빨리 변질되었으나, 재래종의 육색이 개량종보다 붉고 진함을 더 오랫동안 유지하였다. 신선육의 기호도는 진열기간 동안 조도 처리에 의해 빨리 감소하였지만, 재래종이 개량종보다 높은 기호도를 보였다. 결론적으로, 진열기간 동안 재래종 돈육이 개량종 돈육보다 우수한 색택과 신선육 기호도를 보였으나, 개량종 돈육보다 낮은 지방산화 안정성을 보였다. 또한 식육을 조도 처리시 지방산화와 변색이 더 빨리 촉진되었다.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 1995년도 학술대회
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• pp.69-74
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• 1995

An object color can be seen differently under the various outer illuminants. However, human visual system has color constancy that the object color can be seen constantly under the different outer illuminants. When the viewer watches TV under specific outer illuminants, he perceives distorted color due to the emitting spectrum of outer illuminants as well as the radiation of CPT itself. Namely, when the outer illuminants such as fluorescent and incandescent lamps incident on CPT, brightness, saturation, hue, and contrast on color pictures are changed, he perceives distorted color from the original color. In this paper color enhancement algorithm based on light intensity and outer light decision function using RGB sensor was proposed. The implemented TV of proposed algorithm has higher visual quality at the view point of human visual system and more vivid than that of conventional color TV.

• Journal of the Optical Society of Korea
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• 제20권2호
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• pp.276-282
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• 2016

A 2 Gbit/s visible-light communication (VLC) scheme using time-frequency color-clustered (TFCC) multiple-input multiple-output (MIMO) based on blue, cyan, yellow, and red (BCYR) light-emitting diodes (LEDs) is presented. In the proposed scheme, BCYR LEDs are employed to form four different color clusters. Data transmission using the four color clusters is performed in MIMO, so that the scheme achieves a very high speed of data transmission. Moreover, the scheme employs the TFCC strategy to yield high performance in terms of bit error rate (BER). TFCC operates in such a way that the original data and the two delayed versions of the data are multiplied by orthogonal frequencies and then transmitted using a specific color of the BCYR LED. In the receiver, color filters are employed to detect the data transmitted from the desired cluster. Selection combining (SC) is also performed to yield a diversity effect within each color cluster, to further improve the performance. Performance evaluation demonstrates that the proposed TFCC MIMO VLC offers a data rate of 2 Gbit/s and a bit error rate of 4×10^-5, at an E_b/N_o value of merely 3 dB.

• Restorative Dentistry and Endodontics
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• 제19권1호
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• pp.124-134
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• 1994

The shade of restorative materials is very important for successful restoration esthetically harmonized with the natural tooth. The purpose of this study was to evaluate the color stability and the opacity change of conventional chemical setting and visible light curing glass-ionomer cements for restorative esthetic filling. Specimens of each brand (GC Fuji II and Fuji II LC) were uniformly prepared and divided into three groups: In group l(control group), the specimens received no surface treatment; in group 2, the specimens were coated with varnish and the excess gently blown off; and in group 3. the specimens were coated with light-cured bonding resin and irradiated by a visible light curing unit for 20 seconds on both sides. All specimens were stored in distilled water at $37^{\circ}C$ and checked after for 24 hours. 2 months. 4 months, 6 months. and 8 months. The color characteristics($L^*,\;a^*,\;b^*$) and the opacity(Y%) of all the samples were measured by a spectrocolorimeter and the total color differences(${\Delta}E^*$) and opacity changes(${\Delta}Y%$) were computed. The following results were obtained : 1. The total tolor differences in all groups increased with time. 2. The total color differences of the LC groups after immersion for 8 months in distilled water at $37^{\circ}C$ were lower than those of GC groups(p<0.01), and the total color differences of the varnish or the light-cured bonding resin coated groups were lower than those of the control group with glass-ionomer cements which had no surface treatment(p<0.01). 3. In all groups the translucency decreased with time. 4. In the control group and the varnish coating group. the opacity changes of the GC groups were lower than those of the LC groups(p<0.01) and in the light-cured bonding resin coated group, there was no significant difference between the GC group and the LC group. 5. The opacity changes of the varnish or the light-cured bonding resin coated groups were lower than those of the control group(p<0.01). These results suggest that color change and opacity of conventional chemical setting and light cured glass-ionomer cement were increased with time, and the color changes and the opacity changes of a control group after immersion for 8 months in distilled water at $37^{\circ}C$ were greater than those of the varnish or the light-cured bonding resin coated groups.

• 한국광학회지
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• 제16권5호
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• pp.433-439
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• 2005

백색 광원과 컬러 센서를 이용하여 바이오 센서의 발색 정도를 측정하는 측정기를 개발하였다. 컬러 센서의 적색, 녹색 및 청색영역의 빛의 세기를 비율로 나타냄으로서, 조사 광의 세기가 변하는 경우에도 안정적인 분광 정보를 얻을 수가 있었고, 바이오 센서의 화학적 처리 과정에서 발생하는 수막 등의 영향에 의한 오차를 감소시킬 수 있다. 바이오 센서의 발색 변화율이 작은 경우 컬러 센서의 각 영역에 대한 증폭률을 조정하는 것만으로 시스템의 민감도를 향상 시킬 수 있었다.

• 한국광학회지
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• 제20권2호
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• pp.110-117
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• 2009

본 논문은 광원 및 디스플레이 기기의 중요한 품질 지표 중 하나인 색특성 측정과 관련하여 대표적인 측정량인 CIE 1931(x, y) 색좌표, CIE 1960(u, v) 색좌표, 상관색온도(correlated color temperature, CCT), 분포온도(distribution temperature)에 대한 측정불확도 평가방법과 그 산출 예를 소개한다. 분광복사계를 사용하여 광원의 상대분광분포를 측정하고 이로부터 위의 색특성 측정량을 계산하는 경우에 대하여 표준소급체계를 소개하고, 상대분광분포의 불확도가 각 색특성 측정량의 불확도로 전파되는 과정을 파장간 상관관계를 고려한 행렬식을 이용하여 일관되게 유도한 후, CIE A 표준광원, LED 백색광, LCD 백색광에 대해 측정불확도 산출 예를 보였다.