• The Korea Journal of Herbology
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• 제25권1호
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• pp.55-63
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• 2010

Objectives : The object of this study was to verify the inhibitory effect of a decoction of Eucommiae ulmides OLIVER (EU) and Dipsacus asperoides C. Y. Cheng et T.M.Ai (DA) on Collagen II-induced Arthritis Mice (CIA mice). Methods : DBA/1OlaHsd mice were immunized with bovine type II collagen. Boostnig same collagen 21 days later, arthritis was induced and then administrated orally the extract of EU+DA (200 or 50 mg/kg) once a day for 4 weeks and compared with that of methotrexate (MTX, 0.3 mg/kg) as a positive control. Results : Administration of EU+DA suppressed the inflammatory progression of CIA mice and the results were 1. Arthritis index of CIA mice was decreased. 2. EU+DA decreased the production of TNF-$\alpha$, IL-6, IL-$1{\beta}$ in the serum of CIA mice. 3. EU+DA decreased the level of IgM. 4. EU+DAincreasaed $CD3^+$, $CD4^+$, $CD4^+$/CD25 but decreased $CD19^+$, $CD3^+/CD49b^+$(NKT), $CD3^-/CD49b^+$(NK), $B220^+/CD23^+$ in PBMC of CIA mice. 5. EU+DA decreased $CD3^+$, $CD4^+$, $CD3^+/CD69^+$ of paw joint in CIA mice. 6. EU+DA decreased subsynovial inflammation. Conclusions : This results demonstrated that extract of EU+DA suppressed the inflammatory progression of CIA mice and supported further studies are required to clarify a mechanism of therapeutic role.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.344-344
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• 2007

본 연구에서는 X선 영상 검출기로의 적용을 위하여 $Gd_2O_3$:Eu 형광체 필름을 제작하여 X선에 대한 발광 특성을 분석하였다. $Gd_2O_3$:Eu는 저온 액상법을 이용하여 분말 형태로 제조한 후 Particle-in-binder (PIB)으로 필름 형태로 제작한 후, 도핑된 Europium(Eu)의 농도와 소결 온도에 따른 X선에 대한 발광 특성을 분석하였다. Photolumimescence (PL) spectrum에서 611nm에서 가장 높은 발광 효율을 나타내었으며, 입자의 크기가 줄어듦에 따라 610nm에서 새로운 peak가 형성 되었다. 또한 Eu의 농도에 따라서 발광 강도의 차이가 관찰되었는데, 5wt%의 도핑 농도에서 가장 높은 발광 효율을 나타냈으며, 도핑 농도에 매우 의존적인 결과를 나타냈다. 소결 온도에 따른 발광 특성 분석에서, $500^{\circ}C$에서 소결하였을 때는 623nm에서 강한 peak를 나타내는 단사정계상의 발광 peak는 거의 관찰되지 않았으나 소결 온도가 $700^{\circ}C$와 $900^{\circ}C$에서는 peak가 확인되었다. 이를 통해 $Gd_2O_3$ 모체가 대부분 입방 대칭 구조를 가지는 $Gd_2O_3$:Eu가 합성되었음을 확인할 수 있었다. 또한 소결 온도에 따른 발광 강도를 분석한 결과 $900^{\circ}C$에서 소결하였을 때 가장 높은 발광 강도를 나타냈다. Luminescent decay time 측정 결과에서 도핑된 Eu의 농도가 커질수록 Luminescent decay time이 짧아짐을 확인할 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제35권11호
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• pp.3319-3325
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• 2014

Eu(III)-doped $CeO_2$ nanorods were prepared by a co-precipitation method at room temperature, and their photoluminescence profiles were examined with different Eu(III)-doping concentrations and thermal annealing temperatures. Scanning electron microscopy, X-ray diffraction crystallography and UV-Vis absorption spectroscopy were employed to examine the morphology, crystal structure and photon absorption profiles of the nanorods, respectively. Additionally, their 2D and 3D-photoluminescence profile maps were obtained to fully understand the photoluminescence mechanism. We found that the magnetic dipole $^5D_0{\rightarrow}^7F_1$ and the electric dipole $^5D_0{\rightarrow}^7F_2$ transitions of Eu(III) were highly dependent on the doping concentration, annealing temperature and excitation wavelength, which was explained by the presence of different Eu(III)-doping sites (with and without an inversion center) in the $CeO_2$ host with a cubic crystal structure.

• The Journal of Asian Finance, Economics and Business
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• 제8권5호
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• pp.607-616
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• 2021

The European Union Vietnam Free Trade Agreement (EVFTA) took effect on August 1 paving the way for increased trade between the EU and Vietnam; this marked a huge turning point for the Vietnamese economy. Agriculture products, especially fruits, must be listed when it comes to Vietnam export industries that profit the most from EVFTA. After a period of study, with the desire to contribute to the improvement in the efficiency of Vietnam's agricultural products to the EU, the researchers want to assess the impact of the EVFTA on the flows of Vietnamese fruits to the EU market. The study uses a quantitative analysis method via the WITS-SMART model with data on export turnover and tariff reductions in parallel with the analysis of changes in factors affecting the trade flows of fruits between the two markets when the EVFTA takes effect. As a result, Vietnam's fruit importing from the EU is expected to escalate by 29.18% in 2021, while the flow of export will only inch up by 0.955%, which is rather low compare to the increase in import value. Hence, effective policies must be introduced in Vietnam to innovate production methods and increase product quality, so that the EVFTA can be used to boost Vietnam's fruit exports to the EU.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.I
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• pp.717-720
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• 2005

Nanocrystalline $GdBO_3:Eu^{3+}$ was prepared by a hydrothermal method. The as-synthesized powders were spherical shaped agglomerates of nano particles. The luminescent properties were compared with samples synthesized by conventional solid-state reaction method. Both the photoluminescence intensity and chromaticity were improved and a red-shift in the CT band was observed for the hydrothermally synthesized samples.

• Journal of Ceramic Processing Research
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• 제20권3호
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• pp.276-279
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• 2019

New green-emitting Sr4ScAl3O10:Eu2+ phosphor was prepared using a novel melt quenching synthesis method. The temperature of raw materials irradiated with the strong light of the Xe arc-lamp was rose up to about 2273 K, followed by a sharp drop in the temperature after turn off the lamp. This method is a useful tool for rapid screening of novel phosphor materials.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.1514-1517
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• 2005

The $(Y,Gd)BO_3:Eu^{3+}$ phosphor was made by coprecipitation method. The precipitated powders were amorphous. The value of pH in the process of coprecipitation was critical for the luminescence of phosphors. The particle size and morphology were influenced by pH value. The lower calcination temperature and hydrothermal synthesis leads to the distortion of lattices. The distorted lattices changed the symmetry of $Eu^{3+}$ site. The broken inversion symmetry in the distorted lattice caused the increased emission of $^5D_0{\rightarrow}^7D_2$ transition.

• Journal of Korea Trade
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• 제23권2호
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• pp.76-87
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• 2019

Purpose - This study empirically analyzes the effects of the European Union-South Korea Free Trade Agreement on Korean exports in major sectors. Design/Methodology - This study is based on the augmented gravity model with a panel data set covering 51 countries between the years 2000 and 2015. Findings - Main findings of the present study is that the agreement has affected the chemical sector the most. Fixed effects estimation predicted a positive trade effect of 38.3%, while Poisson maximum likelihood estimation predicted an impact of 4.75% in the chemical export sector. Regression results for the other sectors only show insignificant effects. Originality/value - The findings imply that the effects of the EU-South Korea free trade agreement on the Korean exports are quite specific compared to the European ones, meaning that the Korean government should focus on sector-specific programs to maximize the welfare benefits of the free trade agreement.

• Korean Journal of Materials Research
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• 제12권1호
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• pp.21-26
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• 2002

In order to search new phosphors for plasma display panel(PDP), phosphate hosts which has a host excitation band at around 150nm were prepared and their luminescent properties were investigated. In the preparation of $YPO_4: Eu\; and\; (Y,Gd)PO_4: Eu$ phosphors, the effect of oxide and oxalate starting materials on prepared phosphors were compared in terms of relative emission intensities and particle characteristics. The results showed that oxalate starting materials gave better performance in emission intensities and smaller size and more round shape phosphors which would be more applicable for high resolution display. Additionally, Gd, V, Nb and Ta ions were doped to $YPO_4:Eu$ and the luminescent properties of the resulant solid solutions were investigated to find efficient sensitizer. Among these ions, Gd, V and Nb ions increased the emission intensities of parent phosphor to around 10%. While Nb ion gave the best result in emission intensities, CIE color coordinate were improved by doping V ion into $YPO_4:Eu$ phosphor to give x=0.6523, y=0.3406 compared to commercial sample.

• Journal of the Korean Society for Aviation and Aeronautics
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• 제25권4호
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• pp.178-186
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• 2017

Air travel has become an essential part of the global society and its sustainable development is expected. Airlines profit structure and network operation will be influenced by internalization of external costs like emission charge. This additional cost of the airlines will be directly pose air ticket fare increase and demand of air passenger will be decreased. EU-ETS is a part of environmental binding to airlines fly to EU territory airports. This study analyzes the impact of emission charges by application of EU-ETS on airlines network change. For long-term forecast, a reliable estimation of the future price of carbon dioxide (CO2) will be used.