• Journal of Astronomy and Space Sciences
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• v.21 no.2
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• pp.73-82
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• 2004

New photometric and spectroscopic solutions of W-type overcontact binary V 417 Aql were obtained by solving the UBV light curves of Samec et al. (1997) and radial-velocity ones of Lu ＆ Rucinski (1999) with the 2003 version of the Wilson-Devinney binary code. In the light curve synthesis the light of a third-body, which Qian (2003) proposed, was considered and obtained about 2.7%, 2.2%, and 0.4% for U, B, and V bandpasses, respectively. The model with third-light is better fitted to eclipse parts than that with no third-light. Absolute dimensions of V417 Aql are determined from our solution as $M_1$= 0.53 $M_{*}$, $M_2$= 1.45 $M_{*}$, $R_1$= 0.84 $R_{*}$, and $R_2$= 1.31 $M_{*}$, and the distance to it is deduced as about 216pc. Our distance is well consistent with that (204pc) derived from Rucinski ＆ Duerbeck's (1997) relation, $M_{v}$ = $M_{v}$(log P, B-V), but is more distant than that (131$\pm$40pc) determined by the Hipparcos trigonometric parallax. The difference may result from the relatively large error of Hipparcos parallax for V 417 Aql.l.

• Journal of Astronomy and Space Sciences
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• v.29 no.2
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• pp.151-161
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• 2012

An intensive analysis of 148 timings of V700 Cyg was performed, including our new timings and 59 timings calculated from the super wide angle search for planets (SWASP) observations, and the dynamical evidence of the W UMa W subtype binary was examined. It was found that the orbital period of the system has varied over approximately $66^y$ in two complicated cyclical components superposed on a weak upward parabolic path. The orbital period secularly increased at a rate of $+8.7({\pm}3.4){\times}10^{-9}$ day/year, which is one order of magnitude lower than those obtained by previous investigators. The small secular period increase is interpreted as a combination of both angular momentum loss (due to magnetic braking) and mass-transfer from the less massive component to the more massive component. One cyclical component had a $20.^y3$ period with an amplitude of $0.^d0037$, and the other had a $62.^y8$ period with an amplitude of $0.^d0258$. The components had an approximate 1:3 relation between their periods and a 1:7 ratio between their amplitudes. Two plausible mechanisms (i.e., the light-time effects [LTEs] caused by the presence of additional bodies and the Applegate model) were considered as possible explanations for the cyclical components. Based on the LTE interpretation, the minimum masses of 0.29 $M_{\odot}$ for the shorter period and 0.50 $M_{\odot}$ for the longer one were calculated. The total light contributions were within 5%, which was in agreement with the 3% third-light obtained from the light curve synthesis performed by Yang & Dai (2009). The Applegate model parameters show that the root mean square luminosity variations (relative to the luminosities of the eclipsing components) are 3 times smaller than the nominal value (${\Delta}L/L_{p,s}{\approx}0.1$), indicating that the variations are hardly detectable from the light curves. Presently, the LTE interpretation (due to the third and fourth stars) is preferred as the possible cause of the two cycling period changes. A possible evolutionary implication for the V700 Cyg system is discussed.

• Journal of the Korean Society of Radiology
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• v.13 no.6
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• pp.831-840
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• 2019

The X-ray detector by liquid crystal with front light was proposed and verified by a X-ray image. The proposed detector utilizes the visible light instead of the electric signal by transistor. Therefore, it shows low noise and can be fabricated at low cost. The liquid crystal detector uses the orientation change of the liquid crystal molecule by conductivity change of the photoconductive layer. We can get the X-ray image from the transmitted light through the liquid crystal. The X-ray dose was calibrated from the measured transmittance of the visible light after comparison to the reference transmittance curve of the liquid crystal. The amorphous Se was used for photo con ducting layer and parylene was used for the liquid crystal alignment instead of the conventional alignment layer which needs high-temperature process over 200℃. The proposed X-ray detector can decrease the X-ray dose by high sensitivity which was verified by simulation. After the fabrication of the X-ray detector, the X-ray image was obtained as a function of the bias voltage to the liquid crystal. 10 lines/mm resolution was obtained from the line pattern and we will apply it to the 17inch diagonal liquid crystal X-ray detector with 3π retardation.

• Journal of Korean Ophthalmic Optics Society
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• v.10 no.4
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• pp.267-272
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• 2005

We deposited thin films of organic light-emitting-material $Alq_3$(alumina quinoline) on silicon and slide-glass substrates using thermal evaporation method, and measured spectra of ellipsometry angles ${\Delta}$ and ${\Psi}$ in the photon-energy range of 1.5~5.0 eV using a variable angle spectroscopic ellipsometer. The optical constants, refractive index and extinction coefficient, of $Alq_3$ were determined via the dispersion parameters extracted from the curve-fitting process based on Jellison-Modine dispersion function. The reliability of determined optical constants were verified through the comparison of measured and simulated transmittance curves and the good agreement between simulated absorption-coefficient curves and absorbance spectra measured using a spectrophotometer.

• Journal of Astronomy and Space Sciences
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• v.17 no.1
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• pp.39-44
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• 2000

We reinvestigate UV line emissions of 44i Boo, W UMa, AW UMa and VW Cep, which are indicaters of chromospheric activity of these stars. C I, C II, C IV, Si IV lines show significant variation in orbital phase. Among those lines, the Line of C IV showed the strongest line flux. while other Si IV and N V lines showed relative low line intensities. 44i Boo emitted the strongest flux than other stars. UV light curves of target stars shoed UV maximum at phase around 0.2 an 0.8 Such UV emissions are generally believed to be observed at the active regions and contacting parts of the two stars due to the clear visibility at the phase 0.2 and 0.8. Total emissivity of four transitions lines lead to conclude that the activity of this region is 40 times larger than the quiet sun. It is obvious that the activity decrease according to increase period. We obtained also Mg II light curve of AW UMA and VW Cep. These stars showed more clearly phase-dependent light curves. We estimated effective temperature of two star, AW UMa and VW Cep, using by Mg II flux.

• Korean Journal of Plant Resources
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• v.21 no.5
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• pp.357-361
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• 2008

The photosynthetic characteristics of three Ligularia species, L. fischeri, L. fischeri var. spiciformis and L. stenocephala under-tree cultivated in Dunnae-myeon, Hoengsung-gun were measured and compared. Total mean photosynthetic rate increased with increasing the light intensity up to 2,000 PPFD. Mean photosynthetic rate of L. fischeri increased to maximum value of $21.1{\mu}mol\;CO_{2}m^{-2}s^{-1}$ with increasing the light intensity up to 1,600 PPFD, but it was decreased at 2,000 PPFD. The highest photosynthetic rate was shown in L. fischeri var. spiciformis, followed by L. fischeri, and L. stenocephala. was the highest $27.39{\mu}mol\;CO_{2}m^{-2}s^{-1}$ among three species, followed by that of The differences in photosynthetic rates were significantly different among the species each measuring date. L. fischeri var. spiciformis was more adaptive species at the low elevated under-tree cultivated sites, such as, Sanchemaeul Dunnae-myeon Hoeyngseung-gun than L. fischeri and L. stenocephala.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.33 no.1
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• pp.1-6
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• 2022

Vocal fold injection (VFI) is widely accepted as a first line treatment in treating unilateral vocal fold paralysis and other vocal fold diseases. Although VFI is advantageous for its minimal invasiveness and efficiency, the invisibility of the needle tip remains an essential handicap in precise localization. Real-time light-guided vocal fold injection (RL-VFI) is a novel technique that was developed under the concept of performing simultaneous injection with precise placement of the needle tip under light guidance. RL-VFI has confirmed its possibility of technical implementation and the feasibility in injecting the needle from various directions through ex vivo animal studies. Further in vivo animal study has approved the safety and feasibility of the procedure when various transcutaneous approaches were applied. Currently, RL-VFI device is authorized for clinical use by the Ministry of Food and Drug Safety in South Korea and is clinically applied to patients with safe and favorable outcome. Several clinical studies are currently under process to approve the safety and the efficiency of RL-VFI. RL-VFI is expected to improve the complication rate and the functional outcome of voice. Furthermore, it will support laryngologists in overcoming the steep learning curve by its intuitive guidance.

• Archives of Pharmacal Research
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• v.9 no.4
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• pp.211-214
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• 1986

A simultaneous determination method of alkaline earth metals was attempted with the conventional high performance liquid chromatographic system. Four cations, namely, magnesium, calcium, strontium and barium ion, were injected directly as aqueous solution into an eluent containing copper chloride solution and and were successfully separated and determined on a separating column (Zipax SCX, 4.6 mm i.d. ${\times}25$ cm length, Du Pont, USA) by using a variable wavelength UV detector. The linear calibration curves were obtianed in the range from $1.0{\times}10^{-4}M$ to $5.0{\times}10^{-4}M$ and the correlation coefficient of the calibration curve for each metal of magnesium and calcium in tap water. Alkaline earth metals were determined with the conventional high performance liquid chromatographic system.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.2
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• pp.56.2-56.2
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• 2013

We study the three-dimensional genus topology of large-scale structure using the CMASS Data Release 11 sample of the SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS). The CMASS sample yields a genus curve that is characteristic of one produced by Gaussian random-phase initial conditions. The data thus supports the standard model of inflation where random quantum fluctuations in the early universe produced Gaussian random-phase initial conditions. Modest deviations in the observed genus from random phase are as expected from the nonlinear evolution of structure. We construct mock SDSS CMASS surveys along the past light cone from the Horizon Run 3 (HR3) N-body simulations, where gravitationally bound dark matter subhalos are identified as the sites of galaxy formation. We study the genus topology of the HR3 mock surveys with the same geometry and sampling density as the observational sample, and the observed genus topology to be consistent with LCDM as simulated by the HR3 mock samples.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.23 no.5
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• pp.1372-1383
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• 1998

In this paper, modeling for DC and AC characteristics analysis of DFB-LD was performed considering effects of .lambda./4-shifted gratingandspatial hole burning within a laser diode cavity. From the simulation for DC characteristics, Light-Current curve, optical power distribution and carrier density distribution within the cavity can be obtained. The simulation for AC characteristics porovides IM response and the amplitude and phase and the amplitude and phase response of FM with excellent accuracy.