• 제목/요약/키워드: UV Curve

검색결과 174건 처리시간 0.035초

UV 배향된 액정셀에서의 전기광학 특성 (Electro-Optical Characteristics of the UV Aligned LCD Cell)

  • 이병순;이호영
    • 전기학회논문지P
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    • 제62권4호
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    • pp.223-226
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    • 2013
  • In this study, we investigated the electro-optical(EO) characteristic of fringe-field switching(FFS) mode cell by the two kinds of ultraviolet(UV) alignment method on the organic thin film(polyimide: PI). The suitable organic layersfor FFS cell and the aligning capabilities of nematic liquid crystal(NLC) using the in-situ photoalignment method were studied Disclination is observed after conventional photoalignment method for 1h, and in-situ photoalignment method for 1h. Monodomain alignment of the NLC can be observed via in-situ photoalignment method for 2h and 3h. It is considered that NLC alignment is due to photo-depolymerization of the polymer with oblique non-polarized UV irradiation on PI surface. An unstable V-T curve of UV-aligned FFS-LCD with conventional photoalignment method can be achieved. However, a stable V-T curve of UV-aligned FFS-LCD with in-situ photoalignment method(1h), and V-T curve of UV-aligned FFS-LCD with in-situphotoalignment method was much stable comparing with that of other UV-aligned FFS-LCD's. As a result, more stable EO performanceof UV-aligned FFS-LCD with in-situphotoalignment method for 3h is obtained than that of the other UV-aligned FFS-LCD's.

Radiative Transfer Model of Dust Attenuation Curves in Clumpy, Galactic Environments

  • 선광일
    • 천문학회보
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    • 제41권2호
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    • pp.40.2-40.2
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    • 2016
  • The attenuation of starlight by dust in galactic environments is investigated through models of radiative transfer in a spherical, clumpy interstellar medium (ISM). We show that the attenuation curves are primarily determined by the wavelength dependence of absorption rather than by the underlying extinction (absorption+scattering) curve; the observationally derived attenuation curves cannot constrain a unique extinction curve unless the absorption or scattering efficiency is specified. Attenuation curves consistent with the Calzetti curve are found by assuming the silicate-carbonaceous dust model for the Milky Way (MW), but with the $2175{\AA}$ bump suppressed or absent. The discrepancy between our results and previous work that claimed the Small Magellanic Cloud dust to be the origin of the Calzetti curve is ascribed to the difference in adopted albedos; we use the theoretically calculated albedos whereas the previous ones adopted empirically derived albedos from observations of reflection nebulae. It is found that the model attenuation curves calculated with the MW dust are well represented by a modified Calzetti curve with a varying slope and UV bump strength. The strong correlation between the slope and UV bump strength, as found in star-forming galaxies at 0.5 < z < 2.0, is well reproduced if the abundance of the UV bump carriers is assumed to be 30-40% of that of the MW-dust; radiative transfer effects lead to shallower attenuation curves with weaker UV bumps as the ISM is more clumpy and dustier. We also argue that some of local starburst galaxies have a UV bump in their attenuation curves, albeit very weak.

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유기막에 UV 배향한 FFS 액정셀의 전기광학특성 (A study on Electro-Optical Characteristics of the UV Aligned FFS Cell on the Organic Layer)

  • 한정민;황정연;김병용;한진우;김종환;이상극;오용철;서대식
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2006년도 추계학술대회 논문집 Vol.19
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    • pp.278-279
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    • 2006
  • In this study, we investigated the electro-optical (EO) characteristic of fringe-field switching (FFS) mode cell by the two kinds of ultraviolet (UV) alignment method on the organic thin film (polyimide Pl). The suitable organic layers for FFS cell and the aligning capabilities of nematic liquid crystal (NLC) using the in-situ photo-alignment method were studied. An unstable V-T curve of UV-aligned FFS-LCD with conventional photo-alignment method can be achieved. However, a stable V-T curve of UV-aligned FFS-LCD with in-situ photo-alignment method (1h), and V-T curve of UV-aligned FFS-LCD with in-situ photo-alignment method was much stable comparing with that of other UV-aligned FFS-LCD's, As a result, more stable EO performance of UV-aligned FFS-LCD with in-Situ photo-alignment method is obtained than that of the other UV-aligned FFS-LCD's.

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Mg II LINE VARIATION OF 32 CYGNI

  • Kang, Young-Woon
    • Journal of Astronomy and Space Sciences
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    • 제9권2호
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    • pp.154-164
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    • 1992
  • The Mg II lines been extracted from the IUE archival spectra of 32 Cygni to investigate the effect of the atmospheric eclipse. The UV light curve has been reduced from the continuum flux at the center wavelength of 2807.5 ${\AA}$ in the IUE spectra. The equivalent width of the Mg II k absoption line has been measured for each spectra. The results of the light variation and flux tracing of the absorption line at the vicinity of the primary eclipse confirmed the atmospheric eclipse. The atmospheric effect lasted until the phase 0.06 in the absorptin line tracing, while it lasted until the phase 0.02 in the UV light curve, respectively.

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Mg2SiO4 열형광체의 소결공정과 자외선 선량에 대한 TL 특성에 관한 연구 (A Study on The Fabrication of The Sintering Process and The Thermoluminescence Properties of UV Dose about The Mg2SiO4 Thermoluminescent Phosphors)

  • 김영국;손인호;김일홍;송재흥;도시홍;강희동
    • 한국재료학회지
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    • 제12권11호
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    • pp.870-874
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    • 2002
  • $Mg_2$$SiO_4$: Dy, Tb pellets were made by using a sintering process, including pressing and heat treatment. In the present study, the optimum parameters of the sintering for the $Mg_2$$SiO_4$: Dy, Tb pellets obtained such as the pressing pressure, the sintering temperature and the sintering time were in terms of thermoluminescence. Experimental results showed that the main peak of the glow curve for $Mg_2$$SiO_4$: Dy, Tb thermoluminescence dosimeter was clearly correlated with the energy of the UV and with the grain size. The intensity of the TL glow curve increased and its main peak position shifted to lower temperature with increasing UV irradiation time.

A Study on Electro-optical Characteristics of the UV Aligned FFS Cell on the Organic Layer

  • Han, Jeong-Min;Ok, Chul-Ho;Hwang, Jeoung-Yeon;Kim, Byoung-Yong;Kang, Dong-Hun;Kim, Jong-Hwan;Kim, Young-Hwan;Han, Jin-Woo;Lee, Sang-Keuk;Seo, Dae-Shik
    • Transactions on Electrical and Electronic Materials
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    • 제8권3호
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    • pp.135-138
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    • 2007
  • In this study, we investigated the electro-optical (EO) characteristic of fringe-field switching (FFS) mode cell by the two kinds of ultraviolet (UV) alignment method on the organic thin film (polyimide: PI). The suitable organic layers for FFS cell and the aligning capabilities of nematic liquid crystal (NLC) using the in-situ photoalignment method were studied; Disclination is observed after conventional photoalignment method for 1h, and in-situ photoalignment method for 1h. Monodomain alignment of the NLC can be observed via insitu photo alignment method for 2 h and 3 h. It is considered that NLC alignment is due to photo-depolymerization of the polymer with oblique non-polarized UV irradiation on PI surface. An unstable V-T curve of UV-aligned FFS-LCD with conventional photoalignment method can be achieved. However, a stable V-T curve of UV-aligned FFS-LCD with in-situ photoalignment method (1 h), and V-T curve of UV-aligned FFS-LCD with in-situ photo alignment method was much stable comparing with that of other UV-aligned FFSLCD's. As a result, more stable EO performance of UV-aligned FFS-LCD with in-situ photoalignment method for 3h is obtained than that of the other UV-aligned FFS-LCD's.

Linear Sweep Voltammetry와 UV-VIS Spectrophotometry를 이용한 게르마늄 분석 (The Determination of Germanium(IV) by Linear Sweep Voltammetry and UV-VIS Spectrophotometry)

  • 최원형;이진식;김재수;김도훈
    • 분석과학
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    • 제5권1호
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    • pp.7-15
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    • 1992
  • 게르마늄을 Phenylfluorone과 착물을 만들어 과염소산 지지전해질에서 Linear Sweep Voltammetry에 의해 정량하고, 염산용액 중에서 형성된 착물을 UV-VIS Spectrophotometry로 정량한 결과를 비교하였다. 이때 전기화학적인 방법의 경우 정량범위가 $2.5{\sim}80{\mu}g/L$이었고, 분광광도법의 경우는 $10{\sim}300{\mu}g/L$이었다.

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PL Degradation을 활용한 OLED 소자의 사진 이미지 구현 (Realization of Static Image on OLEO using Photoluminescence Degradation)

  • 서원규;문대규
    • 한국전기전자재료학회논문지
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    • 제21권9호
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    • pp.859-862
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    • 2008
  • We have realized static image on organic light emitting diodes (OLEDs) using photoluminescence degradation. Ultraviolet (UV) was irradiated to the glass side of device. UV power was 350 Wand the wavelength was 365 nm. The UV irradiation gives rise to the degradation of photoluminescence. Due to the degradation, the current density-voltage curve was shifted to the higher voltage side and the luminescence was also degraded by the current and photoluminescence drop. The negative imaged films were prepared to control the transmittance of UV. The UV light was passed through the film. By this method, the film image was transferred to the device with reversed image and the static image was realized on the OLED.

ON THE HOMOGENEITY OF THE EXTINCTION LAW IN OUR GALAXY

  • Bondar, A.;Galazutdinov, G.;Patriarchi, P.;Krelowski, J.
    • 천문학회지
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    • 제39권3호
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    • pp.73-80
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    • 2006
  • We analyze the extinction law towards several B1V stars-members of our Galaxy, searching for possible discrepancies from the galactic average extinction curve. Our photometric data allow to build extinction curves in a very broad range: from extreme UV till infrared. Two-colour diagrams, based on the collected photometric data from the ANS UV satellite, published UBV measurements and on the infrared 2MASS data of the selected stars, are constructed. Slopes of the fitted straight lines are used to build the average extinction curve and to search for discrepant objects. The selected stars have also been observed spectroscopically from the Terskol and ESO Observatories; these spectra allow to check their Sp/L's. The spectra of only about 30% of the initially selected objects resemble closely that of HD144470, considered as the standard of B1 V type. Other spectra either show some emission features or belong clearly to another spectral types. They are not used to build the extinction curve. Two-colour diagrams, constructed for the selected B1 V stars, showing no emission stellar features, prove that the interstellar extinction law is homogeneous in the Galaxy. Both the shape of the curve and the total-to-selective extinction ratio do not differ from the galactic average and the canonical value(3.1) respectively. The circumstellar emissions usually cause some discrepancies from the average interstellar extinction law; the discrepancies observed in the extraterrestrial ultraviolet, usually follow some misclassifications.

IUE ARCHIVAL SPECTRA OF 31 CYGNI

  • Kang, Young-Woon
    • Journal of Astronomy and Space Sciences
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    • 제8권1호
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    • pp.53-61
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    • 1991
  • UV light curve of 31 Cygni has been made from the IUE high dispersion specta. The depth of primary minimum of the light curve is 5.2 magnitudes because the B4 star's steep spectral gradient. The light curve has been analyzed by the method of Wilson and Devinney Differential Correction (WD). The radial velocities have been measured using the Mg II h lines. The spectroscopic elements have been determined by the method of WD. The change of the Mg II resonance doublet has been investigated based on the eight representative spectra taken at well distributed orbital phases.

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