• Bulletin of the Korean Chemical Society
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• v.20 no.9
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• pp.1061-1066
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• 1999

The adsorption of CO on W(111) surface in the range of adsorption temperature between 300 K and 1000 K has been studied using AES, LEED, and TDS in an UHV system. After CO saturation at 300 K, four desorption peaks are observed at temperatures (K) of about 400, 850, 1000, and 1100 in thermal desorption spectra, called as α, β1, β2, and β3 state, respectively. The state was attributed to molecular species of CO, which is well known. Because the CO in βstates (especially the β3 state) is still debated as to whether it is dissociative or non-dissociative, the β3 state is mainly discussed. By using the variation method of heating rate in the thermal desorption spectrometry, the desorption energy and pre-exponential factor for the β3 state are evaluated to be 280 kJ/mol and 1.5×10 12 s-1 , respectively. A lateral interaction energy of 5.7 kJ/mol can also be estimated by Bragg-Williams approximation. To interpret the thermal desorption spectra for the β3 state, moreover, those for the model of a first order and a second order desorption are simulated using quasi-chemical approximation. In this study, a model of lying-down CO species is proposed for the β3 state of CO adsorption.

• Journal of Food Hygiene and Safety
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• v.6 no.3
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• pp.185-189
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• 1991

This study was carried out to investigate whether acute toxicity of BST-SR is or not. Single dose of BST-SR was given to both sexes of Spraqe-Dawley rats and ICR mice, subcutaneously. No significant toxic symptom was observed in single treated rats and mice during the experimental period. In gross and microscopic observation, no significantly different abnormality observed between the several organs of tested animals and control animals. Therefore, it was concluded that BST-SR was nontoxic when BST-SR was subcutaneously administered to rats and mice up to 1000 times of clinical dose.

• Journal of Astronomy and Space Sciences
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• v.18 no.1
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• pp.21-26
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• 2001

As part of a long-term program for polar upper atmospheric studies, temperatures and intensities of the OH(3-1) bands were derived from spectrometric observations of airglow emissions over King Sejong station($62.22^{circ}S,\;301.25^{circ}E$). These measurements were made with a Michelson interferometer to cover wavelength regions between 1000nm and 2000 nm. A spectral analysis was performed to individual nights of data to acquire information on the waves in the upper mesosphere/lower thermosphere. It is assumed that the measured fluctuations in the intensity and temperature of the OH (3-1) airglow were caused by gravity waves propagating through the emission layer. Correlation of intensity and temperature variation revealed oscillations with periods ranging from 2 to 9 hours. We also calculated Krassovsky’s parameter and compared with published values.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.5
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• pp.420-423
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• 2001

Combining ability in mungbean was studied in 15 quantitative traits through a 6 $\times$ 6 diallel cross. Both additive and non-additive gene effects were found conditioning the inheritane of nodes of the first peduncle, clusters per plant, clusters on main stem and branches, pods per plant, 1000 seed weight, grain yield per plant, biomass, and harvest index. The additive gene action was found significant for nodes on main stem, average internodal length, branches per plant, pods per cluster, pod length, and seeds per pod. The predominace of additive genetic variance was observed in all traits. For grain yield and yield components, the best combiner were VC3902A, VC1560D and ML-5, while the best combinations were the crosses VC3902A $\times$ ML-5, VC1560D $\times$ ML-5, and NM 92 $\times$ VC1560D.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.6 no.2
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• pp.155-165
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• 1996

Growth of $LiNbO_3$ single crystal by Czochralski method was carried out to study the piezoelectric effects. Piezoelectric coefficients and elastic compliances of the $LiNbO_3$ single crystal were determined by the resonance method of length-extentional mode of bar resonator from the room temperature up to $100^{\circ}C$. Two dielectric constants of $LiNbO_3$ were also determined by measuring the capacitance of the plate specimen. Measured constants were piezoelectric coefficients $d_{15},d_{22},d_{31},d_{33}$ elastic compliances $s^E_{11},s^E_{33},2s^E_{13}+2s^E_{44},s^E_{14}$ and dielectric constants $K^T_{11},K^T_{33}$. As temperature increased, elastic compliances changed very slowly while piezoelectric coeffiecients and dielectric constant $K^T_{33}$ changed very rapidly. Electromechanical coupling constant of zyw ($45^{\circ}C$)-bar was as high as 0.51 in room temperature and nearly constant up to $1000^{\circ}C$. The increase of piezoelectric coefficients was mainly due to the increase of dielectric permittivity.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.31 no.4 s.54
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• pp.329-335
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• 2005

In order to investigate the effects of Saussurea involucrata on (relationship between) aging (and Saussurea involucrata), we examined the activities of antioxidation, in vitro MMP inhibition and UVA-induced MMP-1 expression in human dermal fibroblasts. S. involucrata showed scavenging activities radicals and reactive oxygen species (ROS) with the $IC_{50}$ values of $3.89{\mu}g/mL$ against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and $67.29{\mu}g/mL$ against superoxide radicals in the xanthine/xanthine oxidase system, respectively. At the concentration of $1000{\mu}g/mL$, S. involucrata showed 93.27% inhibition on lipid peroxidation of linoleic acid. S. involucrata inhibited the activities of MMP-1 in a does-dependent manner and the $IC_{50}$ value calculated from semi-log plots was $97.18{\mu}g/mL$. Also, UVA induced MMP expression in human dermal fibroblasts was reduced 42.86% by treatment with S. involucrata, and MMP-1 mRNA expression was reduced in a dose-dependent manner. Therefore S. involucrata was able to significantly inhibit MMP expression in protein and mRNA level. All these results suggested that S. involucrata might act as an anti-aging agent by antioxidation and reducing UVA-induced MMP-1 production.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.2
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• pp.38.1-38.1
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• 2010

We present the results of the survey for submillimeter galaxies in the MS0451 (04h 54m 10.8s, -03d 00m 57.0s) at z = 0.55 and PKS1138-262 (11h 40m 48.25s, -26d 29m 10.1s) at z = 2.16 with the 1.1mm bolometer array AzTEC at the James Clerk Maxwell Telescope. The samples were centered on a prominent large-scale structure overdensity. Submillimeter galaxies seem to be starburst galaxies at high redshift ($z\;\geq\;1$) with high starformation rates ($\sim1000M\odot\;yr^{-1}$) or active galactic nuclei (AGN). We have obtained AzTEC images using the AzTEC data reduction pipeline with the IDL language. Through a bayes' theorem, we determined the extragalaxy catalogue, containing the false-detection rate, completeness, flux deboosting correction, and the source positional uncertainty in this region. We compared the catalogue with HST, DSS, 2MASS observations.

• Journal of Advanced Navigation Technology
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• v.15 no.4
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• pp.571-577
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• 2011

This paper presents a novel balanced filter design based on a metamaterial structure applicable to differential-mode excitation. The metamaterial structure is based on a unit-cell which under a differential-mode excitation behaves like composite right/left-handed(CRLH) metamaterial with filter characteristics. In contrast, the metamaterial unit-cell is below cut-off under a common-mode excitation. Experimental results are used to verify the proposed metamaterial's differential-mode characteristics. The metamaterial is fabricated with a balanced filter design resulting in an operating frequency range of 960~1000 MHz with a insertion loss of 4.1 dB.

• The Journal of the Korea institute of electronic communication sciences
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• v.6 no.5
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• pp.643-648
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• 2011

In this study, SMPS driven LED traffic signal light for Large-scale traffic such as railroad and airport was designed and its electrical and EMI characteristics were measured. The output current of the LED module driven by SMPS was 1.67A for AC and DC input voltage over 10V. The conducted emission measured over 0.15~30MHz frequency range was lower than the allowed quasi-peak and average level, and the radiated noise measured over 30~1000MHz frequency range showed $23.96dB{\mu}V/m$ at 59.96MHz.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.16 no.2
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• pp.69-76
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• 1980

This paper describes the measurement of the underwater noises produced by the engine vibration around the engine room of stern trawler MIS Sae-Ba-Da(2275GT, 3,600 PS) and pole kner M/S Kwan-Ak-San (243 GT, 1000 PS) while the ship is stopping. The underwater noise pressure level was measured with the underwater level meter of which measuring range is 100 to 200 dB(re bLPa). A and B denotes the maximum pressure level measured at right beneath the bottom of the engine room, while the main engine of the Sae-Ba-Da revoluted at 750 and 500 rpm, respectively. C denotes that of the main engine of the Kwan-Ak-San revoluted at 350 rpm, and D that of the generator of the Sae-Ba-Da revoluted at 720 rpm. Thus A, B, C and D were set for the standard sound source for the experiment. The results obtained are as follows: 1. The noise Pressure level at A, B, C and D were 170.5,165,153 and 158dB, respectively. 2. When the check points distanted vertically 1, 10, 20, 30, 40, 50m from the sound source, the underwater noise presure levels were 170.5, 155, 148, 144 and 138 dB and the directional angle was 116\ulcorner in case of A. 3. The sound level attenuated at the rate of 20dB per 10" meters of the horizontal distance from the sound sources. 4. The frequency distribution of the noise was 100Hz to 10KHz and predominant frequency was 700 to 800Hzminant frequency was 700 to 800Hz