• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.1350-1352
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• 2008

Research on down conversion phosphor materials is the key for the development of solid state lighting (SSL). Especially finding alternative red phosphor for white LEDs based on blue or NUV LEDs are important research task. Under this view, we have synthesized a series of $Eu^{3+}$ substituted $La_2W_{2-x}Mo_xO_9$ (x = 0 ~ 2, insteps of 0.1) red phosphor and characterized by X-ray diffraction (XRD) and photoluminescence. XRD results reveal a phase transition from triclinic to cubic structure for $x\;{\geq}\;0$. All the compositions show broad charge transfer band due to charge transfer from oxygen to tungsten/molybdenum and red emission due to $Eu^{3+}$ ions. Select compositions show high red emission intensity compared to the commercial red phosphor under NUV/blue ray excitation. Hence, this candidate can be possible red emitting phosphors for white LEDs.

• 방사선산업학회지
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• 제8권1호
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• pp.1-5
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• 2014

This study investigated the reduction of microbial population and sensory properties in red pepper powders irradiated by gamma ray, electron beam, and X-ray. Populations of total aerobic bacteria and yeast & molds in red pepper powders were decreased by irradiation treatment in a dose-dependent manner. Gamma ray, electron beam, and X-ray at doses above 8 kGy caused 100% inhibition on growth of aerobic bacteria in red pepper powders. Inhibitory activity of X-ray on sterilization of red pepper powders was significantly equal to or higher compared to gamma ray and electron beam. Color and off flavor in red pepper powders were no significant difference among the control and samples irradiated with gamma ray, electron beam, and X-ray. As a result, the gamma ray, electron beam, and X-ray irradiation can be used to sterilize the microbial growth in red pepper powders without quality loss.

• 한국재료학회지
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• 제21권11호
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• pp.611-616
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• 2011

Red-orange phosphors $Gd_{1-x}PO_4:{Eu_x}^{3+}$ (x = 0, 0.05, 0.10, 0.15, 0.20) were synthesized with changing the concentration of $Eu^{3+}$ ions using a solid-state reaction method. The crystal structures, surface morphology, and optical properties of the ceramic phosphors were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), and photoluminescence (PL) spectrophotometry. The XRD results were in accordance with JCPDS (32-0386), and the crystal structures of all the red-orange phosphors were found to be a monoclinic system. The SEM results showed that the size of grains increases and then decreases as the concentration of $Eu^{3+}$ ionincreases. As for the PL properties, all of the ceramic phosphors, irrespective of $Eu^{3+}$ ion concentration, had orange and red emissions peaks at 594 nm and 613 nm, respectively. The maximum excitation and emission spectra were observed at 0.10 mol of $Eu^{3+}$ ion concentration, just like the grain size. An orange color stronger than the red means that $^5D_0{\rightarrow}^7F_1$ (magnetic dipole transition) is dominant over the $^5D_0{\rightarrow}^7F_2$ (electric dipole transition), and $Eu^{3+}$ is located at the center of the inversion symmetry. These properties contrasted with those of a red phosphor $Y_{1-x}PO_4:{Eu_x}^{3+}$, which has a tetragonal system. Therefore, we confirm that the crystal structure of the host material has a major effect on the resulting color.

• 대한안전경영과학회지
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• 제9권6호
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• pp.171-179
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• 2007

The objective of this GM Red-X project was to reduce customer complaints on Kalos, Lacetti, Magnus as reported through 2004.1 - 2005.1 warranty performance. Seatbelt alarm lamp mal-function problem is connected with safety. So it is critical issue. Seatbelt alarm lamp mal-function which caused by buckle occurred 22 cases from 2004.1 to 2005.1.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2000년도 제1회 학술대회 논문집
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• pp.33-34
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• 2000

The effect of $Y^{3+}$ addition to $SrTiO_3:Pr^{3+}$ on the photoluminescence and cathodoluminescence was studied. We discovered that light emitting levels of $Pr^{3+}$ vary by addition of $Y^{3+}$. In $(Sr_{1-x}Y_x)TiO_3:Pr^{3+}$, both the green and red emission are discovered while the red emission prevails in $Sr(Ti_{1-x}Y_x)O_3:Pr^{3+}$ . $Sr(Ti_{1-x}Y_x)O_3:Pr^{3+}$ shows enhancement of red emission by two kinds of enhancement process.

• 한국전기전자재료학회논문지
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• 제25권3호
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• pp.193-197
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• 2012

$Gd_{1-x}VO_4:{Eu_x}^{3+}$ red phosphors were synthesized with changing the concentration of $Eu^{3+}$ ion by using a solid-state reaction method. The crystal structure, surface morphology, and photoluminescence and photoluminescence excitation properties of the red phosphors were measured by using X-ray diffractometer, field emission-scanning electron microscopy, and florescence spectrometer, respectively. The XRD results showed that the main peak of all the phosphor powders occurs at (200) plane. As for the photoluminescence properties, the maximum excitation spectrum occurred at 306 nm due to the charge transfer band from ${VO_4}^{3-}$ to $Eu^{3+}$ ions and the maximum emission spectrum was the red luminescence peaking at 619 nm when the concentration of $Eu^{3+}$ ion was 0.10 mol.

• 한국진공학회지
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• 제20권6호
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• pp.430-435
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• 2011

고상 반응법을 사용하여 $Eu^{3+}$ 이온의 함량비를 변화시키면서 $Y_{1-x}PO_4:{Eu_x}^{3+}$ 적색 형광체를 합성하였다. 모든 적색 형광체의 결정 구조는 $25.88^{\circ}$에 중심을 갖는 (200) 주 회절 피크로 구성되는 정방정계이었으며, 결정 입자의 형상은 $Eu^{3+}$ 이온의 함량비가 증가함에 따라 구형에 근접하고 균일한 크기 분포를 나타내었다. 형광 특성의 경우에, $Eu^{3+}$ 이온의 함량비에 관계없이 모든 세라믹은 파장 593.0과 619.2 nm에 피크를 갖는 각각 적주황색과 적색 형광을 나타내었다. $Eu^{3+}$ 이온의 함량비가 증가함에 따라 여기 스펙트럼의 파장은 약간씩 장파장 쪽으로 이동하면서 흡수 세기는 증가하는 경향을 보였으며, $Eu^{3+}$ 이온의 함량비가 0.15 mol일 때 최대 흡수 및 발광 스펙트럼이 관측되었다.

• 한국해양공학회지
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• 제24권2호
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• pp.53-56
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• 2010

Oil spills and red tide can be very damaging to the environment and fishery farming. These catastrophic accidents must be detected as quickly as possible. In this paper, we report the results of applying the wavelet transform to SAR or marine radar images for the detection of the boundaries of an oil spill or red tide. The application of the wavelet transform to these phenomena looks quite promising in detecting the boundaries of oil spills and red tide areas.

• 한국식품영양학회지
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• 제26권1호
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• pp.101-108
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• 2013

This study investigated the functional nutrition of red yeast rice to added beurre mani$\acute{e}$ in the production of brown sauce. We added X to Y at levels of 0%, 5%, 10%, 15% and 20% and investigated the effects on the viscosity, water content, turbidity, pH, sugar level, reducing sugar, color, and sensory quality characteristics of the resultant brown sauce. The viscosity of Brown sauce was increased with increasing red yeast rice beurre mani$\acute{e}$ while water content and turbidity were decreased. pH was between 4.57~4.91. Sugar level and reducing sugar were increased with increasing red yeast rice powder content. L and a were increased with increasing red yeast rice powder content, and b was decreased. In sensory testing, visual appearance and flavor were highest for brown sauce preparations containing 15% and 20% X. Aftertaste and taste scored the highest for additions of 10% and 15%. For general preference, a 15% addition of X resulted in the highest score. Based on the results, it seems that red yeast rice powder, 15% red yeast rice powder added brown sauce has the highest the general preference.

• 한국재료학회지
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• 제21권12호
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• pp.644-649
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• 2011

[ $A_{3-2x/3}Al_{1-z}In_{z}O_4F:Eu_x^{3+}$ ](A = Ca, Sr, Ba, x = -0.15, z = 0, 0.1) oxyfluoride phosphors were simply prepared by the solid-state method at $1050^{\circ}C$ in air. The phosphors had the bright red photoluminescence (PL) spectra of an $A_{3-2x/3}Al_{1-z}In_{z}O_4F$ for $Eu^{3+}$ activator. X-ray diffraction (XRD) patterns of the obtained red phosphors were exhibited for indexing peak positions and calculating unit-cell parameters. Dynamic excitation and emission spectra of $Eu^{3+}$ activated red oxyfluoride phosphors were clearly monitored. Red and blue shifts gradually occurred in the emission spectra of $Eu^{3+}$ activated $A_3AlO_4F$ oxyfluoride phosphors when $Sr^{2+}$ by $Ca^{2+}$ and $Ba^{2+}$ ions were substituted, respectively. The concentration quenching as a function of $Eu^{3+}$ contents in $A_{3-2x/3}AlO_4F:Eu^{3+}$ (A = Ca, Sr, Ba) was measured. The interesting behaviors of defect-induced $A_{3-2x/3}Al_{1-z}In_{z}O_{4-{\alpha}}F_{1-{\delta}}$ phosphors with $Eu^{3+}$ activator are discussed based on PL spectra and CIE coordinates. Substituting $In^{3+}$ into the $Al^{3+}$ position in the $A_{3-2x/3}AlO_4F:Eu^{3+}$ oxyfluorides resulted in the relative intensity of the red emitted phosphors noticeably increasing by seven times.