• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.110.2-110.2
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• 2011

Nishikida et al. (2006) presented the first far-ultraviolet (FUV) em${\lambda}$ission-line images of the Vela supernova remnant (SNR) obtained with FIMS/SPEAR instrument. Those include C III ${\lambda}$977, O VI ${\lambda}{\lambda}$1032, 1038, Si IV+O IV] ${\lambda}{\lambda}$1393, 1403 (un-resolved), C IV ${\lambda}{\lambda}$1548, 1551 emission-line images. As a following work, we re-constructed these emission-line images using the new-version processed FIMS/SPEAR data. Additionally, we made N IV] ${\lambda}$1486, He II ${\lambda}$1640.5, O III] ${\lambda}{\lambda}$1661, 1666 emission-line images. The new-version images cover the whole region of the Vela SNR and show more resolved features than the old-version. We compare these FUV emission-line images with other wavelength (X-ray, optical, etc.) images obtained in previous studies.

• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.531-533
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• 2015

We have investigated the long term variability of the intensities of the broad-line region emission lines in the UV spectra of Seyfert I galaxy NGC 5548 from 1973-1996. We have obtained the following results: 1) a high level correlation between the intensities of emission lines as well as between intensities of emission lines and continuum fluxes was discovered. With increasing wavelength the correlation in both cases becomes weaker, 2) the relationship between the intensity of emission lines and the flux radiation in the continuum can be expressed by a power law function with coefficients of ${\alpha}{\approx}0.8-1.1$ for different lines. When the difference between the wavelengths of spectral lines and the continuum is increased, the value of the power function decreases, and 3) it was found that the magnitude of the variability of the line intensities are weaker than the range of variability of the continuum fluxes. The magnitude of the variability of the line intensities and the continuum fluxes increase at longer wavelengths.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.4
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• pp.379-385
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• 2006

A stacked white organic light-emitting diode (OLED) having a blue/orange emitting layer was fabricated by synthesizing nitro-DPVT, a new derivative of the blue-emitting material DPVBi on the market. The white-emission of the two-wavelength type was successfully obtained by using both nitro-DPVT for blue~emitting material, orange emission as a host material and Rubrene for orange emission as a guest material. The basic structure of the fabricated white OLED is glass/ITO/NPB$(200{\AA})$/nitro-DPVT$(100{\AA})$/nitro-DPVT:$Rubrene(100{\AA})/BCP(70{\AA})/Alq_3(150{\AA})/Al(600{\AA})$. To evaluate the. characteristics of the devices, firstly, we varied the doping concentrations of fluorescent dye Rubrene from 0.5 % to 0.8 % to 1.3 % to 1.5 % to 3.0 % by weight. A nearly pure white-emission was obtained in CIE coordinates of (0.3259, 0.3395) when the doping concentration of Rubrene was 1.3 % at an applied voltage of 18 V. Secondly, we varied the thickness of the NPB layer from $150{\AA}\;to\;200{\AA}\;to\;250{\AA}\;to\;300{\AA}$ by fixing doping with of Rubrene at 1.3 %. A nearly pure white-emission was also obtained in CIE coordinates of (0.3304, 0.3473) when the NPB layer was $250-{\AA}$ thick at an applied voltage of 16 V. The two devices started to operate at 4 V and to emit light at 4.5 V. The external quantum efficiency was above 0.4 % when almost all of the current was injected.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.220-220
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• 2011

The Ne-Xe plasmas in dense plasma-focus device with coaxial electrodes were generated for extreme ultraviolet (EUV) lithography. The influence of gas mixture ratio, Ne-Xe (1, 10, 15, 20, 25, 30, 50%) mixture gas, on EUV emission measurement, EUV intensity and electron temperature in the coaxially focused plasma were investigated. An input voltage of 4.5 kV was applied to the capacitor bank of 1.53mF and the diode chamber was filled with Ne-Xe mixture gas at a prescribed pressure. The inner surface of the cylindrical cathode was lined by an acetal insulator. The anode was made of tin metal. The EUV emission signal of the wavelength in the range of 6~16 nm has been detected by a photo-detector (AXUV-100 Zr/C, IRD). The visible emission line was also detected by the composite-grating spectrometer of the working wavelength range of 200~1100 nm (HR 4000CG). The electron temperature is obtained by the optical emission spectroscopy (OES) and measured by the Boltzmann plot with the assumption of local thermodynamic equilibrium (LTE).

• Proceedings of the KIEE Conference
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• 2004.07c
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• pp.2020-2021
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• 2004

Distributed optical feedback by gain coupling in V-groove quantum-wire lasers is investigated using InGaAs/AlGaAs active materials grown by metalorganic chemical vapor deposition (MOCVD). In order to avoid grating overgrowth during the fabrication of DFB structures, a newly developed constant MOCVD growth method is employed. Gain anisotropy in emission spectra near Bragg wavelength, resulting from optical feedback along the DFB direction, is clearly observed at room temperature.

• Bulletin of the Korean Space Science Society
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• 2004.04a
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• pp.99-99
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• 2004

We detected and analyzed molecular hydrogen fluorescence in the Taurus Cloud using the Far-ultraviolet Imaging Spectrograph (FIMS) on the STSAT-1 which was launched at SeP. 27 2003. FIMS is optimized for observing diffuse emission lines in the interstellar medium in the wavelength bands of 900-l150 and 1300-1700 angstrom. The Taurus region is a local molecular cloud which is good for studying molecular hydrogen fluorescence emissions. (omitted)

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.887-890
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• 2008

We present 2D slab silicon-based photonic crystal optical insulator to enhance light emission efficiency of light-emitting diode (LED). A 2D slab silicon photonic crystal is designed in such a way that light emitting diode die can be placed in the middle of the silicon photonic crystal. The device creates light propagation forbidden region in horizontal plane for Transverse Electric (TE) light with the wavelength range of 450 nm to 600 nm.

• Journal of Integrative Natural Science
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• v.3 no.1
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• pp.28-32
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• 2010

Thiophene-derivatized pentiptycenes were synthesized and characterized by NMR and UV-Vis spectroscopy. Aggregation behavior of thiophene-derivatized pentiptycenes was monitored by the measurement of fluorescence. Fluorescence intensities for the thiophene-derivatized pentiptycenes and thiophene-derivatized pentiptycenes aggregates were compared. There is no shift in the maximum of the emission wavelength. In the range of water fraction between 20% and 40%, the emission intensity of thiophene-derivatized pentiptycene aggregates remains almost identical. Fluorescence efficiency incresaed by about 5 times higher when the thiophene-derivatized pentiptycenes forms the aggregates in solution.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.8
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• pp.2037-2042
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• 2014

Three methods for gain saturation tone application were compared for optical wavelength division multiplexing transmission using more than 32 channels. The methods are to use high power distributed feedback laser diodes, to use amplified light sources, and lastly to use one saturation tone and several WDM light sources. 1532.3 nm, 1545.7 nm, and 1558.2 nm for the wavelength dependency of the saturation tone were also compared. As a result, the effect of amplified spontaneous emission noise caused by an amplifier was very slight. long wavelength for a saturation tone caused 1 dB gain reduction and its reason was analyzed.

• Korean Journal of Materials Research
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• v.25 no.2
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• pp.100-106
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• 2015

Plasma properties of dielectric barrier discharges (DBDs) at atmospheric pressure were measured and characterized using optical emission spectroscopy. Optical emissions were measured from argon, nitrogen, or air discharges generated at 5-9 kV using 20 kHz power supply. Emissions from nitrogen molecules were markedly measured, irrespective of discharge gases. The intensity of emission peaks was increased with applied voltage and electrode gap. The short wavelength peaks (315.9 nm and 337.1 nm) measured at the middle of DBDs were significantly increased with applied voltage. The optical emission from DBDs decreased with the addition of oxygen gas, which was especially significant in argon discharge. Emission from oxygen molecules cannot be measured from air discharge and argon discharge with 4.8% oxygen. The emission intensity at 337.1 nm and 357.7 nm related with nitrogen molecule was sensitively changed with electrode types and discharge voltages. However, the pattern of argon emission spectrum was nearly the same, irrespective of electrode type, oxygen content, and discharge voltage.