• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
• /
• pp.484-484
• /
• 2012

OLED는 유기재료를 사용하는 특수성 때문에 선명한 고품질의 화질을 얻을 수 있다. 유기재료에 따른 수명이 정해져 있지만 열에 약한 재료를 사용하기 때문에 출력되는 색의 변화를 동반할 만큼 불안정 하다. OLED는 RGB를 순서에 따라 유리 기판 상에 나열한 구조이며 각 화소의 양극과 음극은 가로와 세로로 서로 직교하고 있다. 이러한 OLED의 구조 때문에 직, 간접적으로 전이되는 열과 OLED Device에서 발생하는 자체 열로 인하여 유기소자의 특성이 변형되는, 이른바 열화현상에 쉽게 노출되어 있다. OLED Device를 제작한 후 72시간동안 8V의 전압을 인가하여 열화현상을 촉진시킨 Aging샘플을 확보 하였다. Aging된 Device의 인가전압을 3V ~ 6V까지 변화를 주고 측정해본 결과 각각의 모든 전압에서 Aging Device의 Nomalized Intensity가 상대적으로 20% 감소했음을 확인 하였다. 또한 Aging 된 Device는 As is Device에 비해 단파장 쪽으로 Shift 되는 결과를 보여주었다. 이를 분석하기 위해 CIE 색 좌표계의 NTSC (National Television System(s) Committee)를 이용하였는데, 범위 안에 있던 As is Device의 색 좌표가 Aging 후에는 NTSC범위 밖으로 이동하였는데, 이는 열화현상이 발생하기 전에 비해 방출되는 빛의 파장이 변했다는 것을 의미하며 정확한 색 재현이 안 된다는 것을 보여준다. 또한 I-V특성을 보면 Aging Device의 구동전압 (3.3V) 이 As is Device (2.7V) 에 비해 더 커지는 것을 확인하였는데 이것은 스트레스로 인해서 발생한 트랩에 의하여 캐리어의 이동도가 떨어졌기 때문에 구동 전압이 증가한 것으로 확인할 수 있다. 연구 결과를 통하여 OLED Device의 사용시간 누적에 따른 열화현상은 색 재현성과 휘도의 저하 그리고 구동전압 증가에 영향을 미친다는 것을 확인 하였다.

• 한국가구학회지
• /
• 제26권2호
• /
• pp.138-144
• /
• 2015

Among several thermal wood modification methods German oil heating technology was applied for color changing larch and paulowniawood specimens. They were heat treated at $200^{\circ}C$ for 3 hours in an autoclave filled with linseed oil. The CIE $L^*a^*b^*$ color indexes of the shells and cores of the oil heated specimens were measured. The color difference indexes between the oil heated and the control specimens of larch and paulowniawood were in the range of 6 and 12, which implies considerably different. The color difference indexes between the core layers of the larch and paulowniawood specimens were 4.3 and 1.7, respectively. It could be concluded that the specimens of the two species were color changed uniformly by oil heating.

• 한국축산식품학회지
• /
• 제39권6호
• /
• pp.863-876
• /
• 2019

The thermal-death times of Listeria monocytogenes were determined in inoculated restructured goat steak at 60℃, 65℃, and 70℃ of sous-vide temperatures. D-values of L. monocytogenes in inoculated restructured goat steak ranged from 7.27 min at 60℃ to 0.46 min at 70℃. Times need to yield at least a 6 log reduction of L. monocytogenes at their temperatures for this product were 47, 12, and 3 min, respectively. After sous-vide, all microbial counts in non-inoculated samples were not detectable, except the aerobic and anaerobic mesophilie and lactic acid bacteria counts were lower than 2 Log CFU/g. For sous-vided and grilled sous-vided samples, sous-vide loss and surface shrinkage were the lowest in samples sous-vided at 60℃ for 47 min (p<0.05). These samples demonstrated the lowest CIE L^*, shear force, hardness, gumminess and chewiness and the highest CIE a^* and hue angle (p<0.05). Therefore, sous-vide at 60℃ for 47 min provided convenient ready-to-cook restructured goat steak for microbiology safety and optimization of physicochemical quality.

• 한국안광학회지
• /
• 제5권2호
• /
• pp.201-205
• /
• 2000

혼합색에 의한 착색 렌즈의 칼라는 감산혼합 법칙을 따르며 착색 렌즈 평가는 광흡수의 특성과 칼라분석에 의한다. Yellow(x)-Blue(1-x) 칼라 렌즈의 광흡수 특성은 500 nm 이하 단 파장에서 황색에 의해(x) 의존하고 550~650 nm 영역 흡수는 청색에 의존하며, 이 흡수 band는 전이금속의 ion화에 의한 peak이다. CIE system인 $L^*a^*b^*$에 의해 분석한 Yellow(x)-Blue(1-x) 칼라 렌즈의 color 특성은 x가 작아질수록 $+a^*$쪽으로 이동하였고 모두 +0.6이내 존재해 채도가 낮은 순수 칼라를 형성하였다.

• 한국분말재료학회지
• /
• 제23권6호
• /
• pp.453-457
• /
• 2016

In this work, we synthesize brilliant yellow color ${\alpha}$-FeOOH by controlling the rod length and core-shell structure. The characteristics of ${\alpha}$-FeOOH nanorods are controlled by the reaction conditions. In particular, the length of the ${\alpha}$-FeOOH rods depends on the concentration of the raw materials, such as the alkali solution. The length of the nanorods is adjusted from 68 nm to 1435 nm. Their yellowness gradually increases, with the highest $b^*$ value of 57 based on the International Commission on Illumination (CIE) Lab system, by controlling the nanorod length. A high quality yellow color is obtained after formation of a silica coating on the ${\alpha}$-FeOOH structure. The morphology and the coloration of the nal products are investigated in detail by X-ray diffraction, scanning electron microscopy, UV-vis spectroscopy, and the CIE Lab color parameter measurements.

• IEIE Transactions on Smart Processing and Computing
• /
• 제4권4호
• /
• pp.272-280
• /
• 2015

This paper proposes color databases that can be used for various purposes for people with a color vision deficiency (CVD). The purpose of this paper is to group colors within the sRGB gamut into the CIE $L^*a^*b^*$ color space using the Brettel algorithm to simulate the representative colors of each group into colors visible to people with a CVD, and to establish a confusion line database by comparing colors that might cause confusion for people with different types of color vision deficiency. The validity of the established confusion lines were verified by using an Ishihara chart. The different colors that confuse those with a CVD in an Ishihara chart are located in the same confusion line database for both protanopia and deutanopia. Instead of the 3D RGB color space, we have grouped confusion colors to the CIE $L^*a^*b^*$ space coordinates in a more distinctive and intuitive manner, and can establish a database of colors that can be perceived by people with a CVD more accurately. Editor - Highlight - Do these changes reflect the intended meaning? If not, please rephrase as intended.

• 한국재료학회지
• /
• 제21권6호
• /
• pp.295-298
• /
• 2011

ZnS:Mn, Dy yellow phosphors for White Light Emitting Diode were synthesized by a solid state reaction method using ZnS, $MnSO_4{\cdot}5H_2O$, S and $DyCl_3{\cdot}6H_2O$ powders as starting materials. The mixed powder was sintered at $1000^{\circ}C$ for 4 h in an air atmosphere. The photoluminescence of the ZnS:Mn, Dy phosphors showed spectra extending from 480 to 700 nm, peaking at 580 nm. The photoluminescence of 580 nm in the ZnS:Mn, Dy phosphors was associated with $^4T_1{\rightarrow}^6A_1$ transition of $Mn^{2+}$ ions. The highest photoluminescence intensity of the ZnS:Mn, Dy phosphors under 450 nm excitation was observed at 4 mol% Dy doping. The enhanced photoluminescence intensity of the ZnS:Mn, Dy phosphors was explained by energy transfer from $Dy^{3+}$ to $Mn^{2+}$. The CIE coordinate of the 4 mol% Dy doped ZnS:Mn, Dy was X = 0.5221, Y = 0.4763. The optimum mixing conditions for White Light Emitting Diode was obtained at the ratio of epoxy : yellow phosphor = 1:2 form CIE coordinate.

• 한국재료학회지
• /
• 제13권8호
• /
• pp.509-513
• /
• 2003

In the present investigation, $La^{3＋}$ and $Ce^{V}$ ions were substituted for $Y^{3＋}$ in the $YBO_3$: Tb in various concentrations. It has been found that these phosphors form solid solutions within limited concentration ranges Excitation and emission spectra under 254 nm and 147 nm were investigated for these phosphors to evaluate influences of $La^{3＋}$ and $Ce^{3＋}$ ions on brightness and CIE color coordinates. It has been observed that brightness of $(Y, La)BO_3$: Tb under 254 nm and 147 nm when $La^{3＋}$ ions are added show an increase of 2.7 times and 1.25 times, respectively. On the other hand, emission intensities of peaks in $Y_{0.8-x}$ $BO_3$: $Tb_{0.2}$ , $Ce_{x}$ show continuos decrease as $Ce^{3＋}$ / content is increased from 0 to 0.4. CIE color coordinates of prepared phosphors show yellowish green which is needed to be improved to be used for display applications.

• Journal of Electrical Engineering and Technology
• /
• 제13권4호
• /
• pp.1673-1681
• /
• 2018

In this paper, the fabrication of a white light-emitting diode (WLED) package capable of producing different color rendering indexes (CRI ($R_a$)) using different types of phosphors (YAG:Ce, Silicate, Nitride, LuAG) for the LEDs is presented. The color quality is evaluated based on the current and temperature variation conditions. The evaluation method for color quality compares the existing CIE 13.3 method and the new IES TM-30-15 method. The CRI ($R_a$) defined in the conventional CIE 13.3 has the disadvantage. This cannot offer any information relevant to the user's preference. However, the newly proposed IES TM-30-15 method suggests the additional measure related to user's preference such as Color Gamut ($R_g$). The present experimental results obtained using the IES TM-30-15 show that the color quality of the WLEDs using green and red phosphors are better than that of the WLEDs using yellow phosphor, but their luminous efficacies are lower. The color quality of WLEDs using green and red phosphors are more stable than that of the WLEDs using yellow phosphor, for current and temperature variations, and it is verified that the phosphor causes this change. The evaluation method for color quality, based on IES TM-30-15, is proved to be capable of overcoming the problems of the existing evaluation methods by this study.

• 한국정보통신학회:학술대회논문집
• /
• 한국해양정보통신학회 2008년도 지능정보 및 응용 학술대회
• /
• pp.142-145
• /
• 2008

본 논문에서는 self-organizing map(SOM)과 grassfire 기법을 이용한 계산 효율적인 컬러 영상 분할 방법을 제안한다. SOM에서 출력 뉴런 수를 축소하고 학습에 사용하는 입력 데이터를 줄임으로써 실행 시간을 단축 시켰다. 입력 영상을 CIE $L^*u^*v^*$ 컬러 공간으로 변환하고 3개의 입력 뉴런과 $4{\times}4$ 또는 $3{\times}3$ 출력 뉴런 구조의 SOM을 이용해 학습한다. 학습 완료 후 입력 영상의 픽셀에 대응하는 출력 값을 구하고 grassfire 기법을 이용해 지역적으로 인접하고 출력 값이 동일한 픽셀들을 하나의 영역으로 결합한다. 다양한 영상을 이용한 실험을 통해 제안한 방법이 컬러 영상 분할에서 기존의 방법에 비해 좋은 결과를 얻을 수 있음을 확인하였다.