• Journal of Electrical Engineering and Technology
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• v.2 no.4
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• pp.518-524
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• 2007

This paper describes several improved characterizations of the EPIC CCD, which now has modified electrode and channel structures. From a 3-D numerical simulation of the device, its channel doping and potential distributions are then observed for the optimization of the charge transfer. A wavelength-dependence on the device structure is observed in terms of the reflectivity of the incident radiation. The optical properties of ultra-low energy levels, when using an open-electrode structure, are then considered to improve their quantum efficiency.

• Journal of Microbiology and Biotechnology
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• v.23 no.9
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• pp.1287-1292
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• 2013

Extracellular biogenic synthesis of silver nanoparticles with various shapes using the rice bacterial blight bacterium Xanthomonas oryzae pv. oryzae BXO8 is reported. The synthesized silver nanoparticles were characterized by UV-Vis spectroscopy, powder X-ray diffractometry (XRD), scanning electron microscopy, energy dispersive X-ray spectrometry, and high-resolution transmission electron microscopy (HR-TEM). Based on the evidence of HR-TEM, the synthesized particles were found to be spherical, with anisotropic structures such as triangles and rods, with an average size of 14.86 nm. The crystalline nature of silver nanoparticles was evident from the bright circular spots in the SAED pattern, clear lattice fringes in the high-resolution TEM images, and peaks in the XRD pattern. The FTIR spectrum showed that biomolecules containing amide and carboxylate groups are involved in the reduction and stabilization of the silver nanoparticles. Using such a biological method for the synthesis of silver nanoparticles is a simple, viable, cost-effective, and environmentally friendly process, which can be used in antimicrobial therapy.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.45.1-45.1
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• 2014

structure of matters of Lambda cold dark matter (CDM) cosmology on detailed numerical simulations. To accomplish our research goal, we have added the following baryonic physics on the existing cosmological hydrodynamic code, Gadget-2: 1) radiative heating and cooling, 2) reionization of the Universe and UV shielding, 3) star formation, 4) energy and metallicity feedback by supernova. In addition, we included cluster formation to distinguish clustered star formation inside the very high density gas clumps from the field star formation. Our simulations cover a cubic box of a side length 4Mpc/h with 130 million particles. The mass of each particles is $3.4{\times}104Msun$, thus the GCs can be resolved with more than hundreds particles. We discuss various properties of the GCs such as mass function, specific frequency, baryon-to-dark matter ratio, metallicity, spatial distribution, and orbit eccentricity distribution as functions of redshift. We also discuss how the formation and evolution of the GCs are affected by UV shielding.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.581-584
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• 2008

$BaMgP_2O_7$:Eu,Mn phosphors for white emission were synthesized and their luminescent properties were investigated under UV excitation. The phosphor emits two colors: a blue band by $Eu^{2+}$ and a red band by $Mn^{2+}$. Due to the efficient energy transfer from $Eu^{2+}$ to $Mn^{2+}$, the red emission positioned at 615 nm is greatly enhanced with increasing $Mn^{2+}$ content up to 17.5 mol%.

• Journal of Information Display
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• v.12 no.4
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• pp.205-208
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• 2011

Herein, the integration of solution-processed polymer thin-film transistors (TFTs) that were fabricated using selective wettability through ultraviolet (UV) exposure into a reflective liquid crystal display is demonstrated. From the experimental results of energy-dispersive spectroscopy, the composition of carbon and fluorine enhancing the hydrophobicity in the polymer chains was found to play a critical role in the wetting selectivity upon UV exposure. The polymer TFTs fabricated through the wettability-patterning process exhibited long-term stability and reliability. This wetting-selectivity-based patterning technique will be useful for constructing different types of solution-processed electronic and optoelectronic devices.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07a
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• pp.431-434
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• 2002

This paper reports on the evaluation of weathering resistance, tracking test and salt-fog of various kinds of cycloaliphatic epoxy systems. It was found that UV irradiation induced the loss of hydrophobic level due to the chain scission attack at the surface. It could be seen that samples containing an UV absorbent/antioxidant and a silicone oil additive knave a good performance in weathering ageing, whereas ATH filled ones have high resistance against tracking failure than others. Under salt-fog test, specimens mixed with silicone oil could suppress leakage current development. It was thought that silicone oil mixed into cycloaliphatic epoxy system could lead to lower the surface energy and to retain hydrophobic properties for a long time, which are desirable for outdoor performances.

• Textile Coloration and Finishing
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• v.21 no.2
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• pp.40-47
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• 2009

Dimethylaminopropyl methacryamide was photografted onto PET fabrics by continuous UV irradiation under ambient conditions. Several factors affecting the photografting were studied including irradiation energy, monomer and photoinitiator concentrations. ATR and ESCA analysis showed the successful grafting of the monomer onto the PET surface. The grafted PET fabrics showed higher zeta potentials below pH 7 compared with the ungrafted PET. The dyeability of the grafted PET fabrics to two $\alpha$-bromoacrylamide reactive dyes was investigated under various dyeing conditions including dye concentration, pH, dyeing temperature and time. The grafting imparted the reactive dyeability to PET fabrics, which was proportional to the grafted monomer content. The reactive dyeing behavior of the grafted PET fabrics was similar to that of conventional wool fabrics.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.7
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• pp.449-453
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• 2016

The amount of electrical energy has been increased with the rapid development of the industrial society. Accordingly, operating voltage of the power equipment and facility capacity are continuously increasing. Development trends of recent high-voltage electrical equipment are ultra high-voltage, large-capacity and compact. Early diagnosis of a failure of the power plant has been emerging as an important task as to supply high quality power to users. In this study, we have tried to develope an algorithm for distinguishing an arc fault signal generated in the power plant by using UV sensor.

• Textile Coloration and Finishing
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• v.20 no.4
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• pp.1-7
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• 2008

Methacryloxypropyl trimethoxysilane (MAPTMS), a hybrid organic-inorganic monomer, was photografted onto PET fabric using benzophenone (BP) as a photoinitiator. It was found that a UV energy of 43.2J/$cm^2$ was required to optimally photograft the MAPTMS onto PET fabrics which was applied with an aqueous formulation of 10% MAPTMS, 20% BP and 0.5% N-Methyldiethanol amine (MDEA). The MDEA additive was efficient in reducing atmospheric oxygen inhibition of polymer radicals which eliminated compulsory nitrogen inerting. The surface grafting of PET fabrics was verified by fourier transform infrared spectroscopy (FT-IR) and scanning electron spectroscopy (SEM). The grafted PET fabrics with the hybrid monomer showed higher thermal stability due to the introduced silane component in the monomer as ascertained by higher char content at 800$^{\circ}C$, which increased to 14.5% for the 15.8% grafting compared to 8.2% for the untreated.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.140.1-140.1
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• 2011

최근 자동차용 휘발유에 메탄올을 불법 혼합시켜 유통시키는 사례가 빈번히 적발되고 있다. 정상적인 연료에 알코올이 불법 혼합될 경우, 장치 내 고무류와 금속류를 부식시키며, 독성가스인 알데하이드를 배출시키는 것으로 알려져 있다. 또한 에탄올의 경우 흡습성이 높아 자체적으로 수분을 생성시킬 수 있으며 정상 휘발유보다 증기압이 높기 때문에 밀폐공간에서 화재 및 질식의 위험이 있을 수 있다. 현재 휘발유 내에 알코올 성분을 분석하기 위한 분석법으로는 Gas Chromatography가 이용되고 있으나 고가의 장비와 긴 분석시간으로 인해서 유사석유의 판별여부가 효율적으로 이루어지지 않고 있다. 본 연구에서는 화학절 식별제인 크롬산($CrO_3$)을 이용하여 휘발유 내 알코올 성분을 정성 정량 분석하였다. 환원된 3가 크롬은 용액상에서 붉은색을 나타내므로 육안으로도 알코올의 존재여부를 간단히 확인할 수 있으며, UV-Vis Spectrophotometry를 통해 휘발유 내 알코올의 농도에 따라 흡광도값이 증가하는 것을 확인할 수 있었다.