• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.8
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• pp.1799-1804
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• 2005

We have developed and estimated the measurement system of $CO_2$ and Nd:YAG laser power of wide range. The absorber is made of gold-plated copper cavity. The calibration heater is using a manganin(CuMn12Ni) coil, and output power is measured by using or resistance bridge with composed manganin and copper coil. Developed system can measure 5${\~}$1000W laser output power range. Calibration factors are 489.13J/mV at 100W and 497.04(J/mV) at 500W. correction factors are 0.99 at 100W and 1.006 at 500W.

• Proceedings of the KIEE Conference
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• 2005.07b
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• pp.1681-1683
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• 2005

The molten carbonate fuel tell(MCFC) is endowed with the high potential especially in future electric power generation industry by its own outstanding characteristics. KEPCO(KEPRI) started a 100 kW MCFC system development program in 1993 and has been executed 100kW system develpilot plant successfully completed first phaseopment by 2005 on the basis of successful results of 25kW system development. In this program, the components and mechanical structure for 100 kW stack and system construction were completed on last year and now system pre-commissioning was being executed. A 100 kW MCFC power plant was constructed at the site of Boryeong Thermal Power Plant. A 100 kW MCFC system has characterized as a high pressure operation mode, $CO_2$ recycle, and externally reforming power generation system. The 100 kW MCFC system consisted with stacks which was made by two 50 kW sub-stacks, 90 cells with 6,000 cm2 active area and BOP including a reformer, a recycle blower, a catalytic burner, an inverter, and etc. The system will be operated under 3 atm pressure condition and expected to last over 5,000 hours by the end of this year.

• Archives of Pharmacal Research
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• v.28 no.12
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• pp.1400-1404
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• 2005

The aim of the present study was to develop the aqueous parenteral formulation containing propofol using o/w microemulsion systems. Propofol itself was chosen as the oil phase and its content was fixed to 1$\%$, w/w. Pseudoternary phase diagrams were constructed to obtain the concentration range of surfactant and cosurfacatnt and the optimum ratio between them for microemulsion formation. Consequently, the suitability of the chosen microemulsion system as a parenteral formulation was evaluated from the stability and hemolysis tests on that. Among the surfactants and cosurfactants screened, the mixture of Solutol HS 15-ethyl alcohol (5/1) showed the largest o/w mocroemulsion region in the phase diagram. When 1 $\%$ (w/w) of propofol was solubilized with 8$\%$ (w/w) of Solutol $HS^{circledR}$??? 15-ethyl alcohol (5/1), the average droplet size (150 nm) and the content of propofol in the systems were not significantly changed at 40$^{circ}C$ for 8 weeks. The hemolysis test showed that this formulation was nontoxic to red blood cells. In conclusion, propofol was successfully solubilized with the o/w microemulsion systems.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.1
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• pp.38-49
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• 1985

The water soluble organic fractions (WSOF) from an agricultural soil (W), a soil treated with sludge for 6 years ($WS_6$), a sludge-soil mixture incubated for one week ($WS_1$), and sewage sludge (SS) were extracted, purified, and characterized by elemental analysis, functional group determinations, infrared, UV-visible, and proton nuclear magnetic resonance spectrosocpy. The SS was characterized by higher organic H, N, and P contents, a higher H/C ratio, and a lower C/N ratio than W. Total acidity carboxyl and phenolic hydroxyl group contents were generally highest in SS, intermediate in $WS_6$ and $WS_1$, and lowest in W. Overall aromatic character and aromatic carboxyl group contents were highest in W, and lowest in SS. Aliphatic proton, aliphatic carboxyl, and phenolic hydroxyl group contents were highest in SS, and lowest in W. Protein decomposition products were the pronounced components in SS, and decreased in concentration as the sludge component in the mixtures decreased. The $^1H$-NMR spectra suggested that the SS-protons were bound to a wider range of functional groups than W-protons. Structural complexities around the aromatic protons followed the following order: SS>$WS_1$>$WS_6$>W.

• Food Science and Preservation
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• v.21 no.6
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• pp.851-858
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• 2014

Muscat Bailey A (MBA) wine was fermented using the indigenous Korean Saccahromyces cerevisiae strains S13 and D8, and the fermentation characteristics were compared with those of S. cerevisiae W-3, an industrial wine yeast. The strains S13 and D8 showed delayed alcohol fermentation compared with the W-3 strain, but the final alcohol contents of the S13 and D8 wines after fermentation were similar to those of the W-3 wine. The S13 wine showed significantly lower malic-acid content than the W-3 wine, but the D8 wine showed a similar level. Both the wines fermented using the S13 and D8 strains showed significantly lower acetaldehyde, methanol, and fusel oil contents, including n-propanol, iso-butyl alcohol, and iso-amyl alcohol, compared to the W-3 wine. Especially, the methanol content was 98.6 mg/L in the S13 wine and 112.0 mg/L in the D8 wine, which were much lower than 192.8 mg/L in the W-3 wine. The S13 wine obtained the highest score in terms of color among the three wines in the sensory evaluation, with lower Hunter's L, a, and b values compared to the W-3 wine.

• Journal of Korean Society on Water Environment
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• v.29 no.2
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• pp.196-203
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• 2013

Seungchon Weir was constructed in 2010 on the downstream region of Yeongsan River watershed for four major river projects. The purpose of our study was to determine whether fish compositions and distributions differ between the upper ($U_w$) and lower regions ($L_w$) of Seungchon Weir during May - December 2011 along with hydroacoustic fish surveys using Eco-Sounder monitoring ($E_SM$) technique. Total number of fish species sampled by conventional fish sampling at all sites was 29, and 21 and 24 species occurred in the $U_w$ and $L_w$, respectively. Most dominant species was Hemiculter eigenmanni (43%) in the $U_w$ and Opsaiichthys uncirostris amurensis (21%) in the $L_w$, indicating a distinct differences of the species composition. According to hydroacoustic approach of ESM, fish density was significantly higher (p < 0.05) in the $L_w$ section of 250 m than any other sections, This outcome indicates that fishes moving toward the upstream were blocked by weir construction. According to analysis of tolerance guilds, tolerant species (TS) were made of 88% and 79% in the $U_w$ and $L_w$ region, respectively, while the proportions of sensitive species were < 0.1% of the total in the both regions. Trophic guild analysis showed that the proportion of omnivore species were 58% and 40% in the $U_w$ and $L_w$ region, respectively, while insectivores were made of 16% and 21% in the $U_w$ and $L_w$ region, respectively. Both analyses of tolerance guilds and trophic guilds indicate the biological degradation of the waterbody. Fish community structure analysis, based on species diversity, dominance, and evenness indices, showed higher community stability in the $L_w$ region than $U_w$ region. Exotic species of largemouth bass were largely increased in this survey (14%), compared to the past (< 1%), indicating a modification of fish trophic structure.

• Journal of the Korean Vacuum Society
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• v.20 no.4
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• pp.266-270
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• 2011

This paper suggest tungsten (W)-carbon (C)-nitrogen (N) thin films for diffusion barrier that W is main material and C and N are additives. W-C-N thin films are deposited with fixed rates of W and C but with a variation of $N_2$ gas flow and W-C-N thin films are heated at $600^{\circ}C$. From the experimental results, the variation of elastoplastic region for W-C-N thin film measured by tribological property is larger than that of elastic region with a variation of $N_2$ gas flow. These results show that the $N_2$ gas flow is more directly related with the elastoplastic region of W-C-N thin film. Nanoindenting test executed 16 times consecutively and we got the stress-strain curve graphs and hardness datas at each sample. Through the stress-strain curve graphs, the standard diviation of stress-strain curve for $N_2$ gas flow rate of 2.0 sccm is smaller than that of 0, 0.5, 1.5 sccm. Consequently, the physical stability of W-C-N thin film depends on the flow rate of $N_2$ gas.

• Korean Journal of Microbiology
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• v.42 no.1
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• pp.1-6
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• 2006

Saccharomyces cerevisiae Dna2 helicase/endonuclease plays an essential role in removing DNA primers during Okazaki fragment processing in eukaryotic DNA replication. Genome-wide scale co-immunoprecipitation experiments predicted that Dna2 interacts with a novel protein YHR122W (1). In this study, we observed that overexpression of YHR122W gene suppressed the temperature-sensitive phenotype of $dna2\Delta405N$ mutation. To investigate direct interaction between these two proteins, a histidine-tagged recombinant YHR122W protein was expressed and purified from E. coli. Physical interaction between the purified YHR122W and Dna2 proteins was detected by enzyme-linked immunosorbent assays. Further more, the complex formation was most efficient at physiological salt concentration, 150 mM NaCl. The genetic and physical interactions between YHR122W and Dna2 shown in this study suggest that the biological functions of these two proteins may be closely related each other.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.10 no.5
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• pp.271-276
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• 2010

This study manufactured spot lighting fixtures for the broadcasting stage and LED lighting fixtures, measured the illumination, dimming, and color temperature, and installed LED lighting and spot Fresnel lighting to the camera by turns with the same subject to confirm and look into the possibility of replacement of LED lighting fixtures by shooting the figures and comparing them. The analysis of the photographed subject found that the lighting apparatus of LED 144[W] was superior to the tungsten halogen illuminator of 1 [kW] in terms of brightness and color of an image. The measuring of the energy used in 144 [W] LED lighting equipment and tungsten halogen 1[kW] lighting equipment suggested that LED saved more than 80 [%] of energy in the same intensity of illumination. The comparison of the light distribution and light intensity distribution of halogen tungsten illuminator of 1[kW] and LED 144[W] lighting apparatus found that when a subject received concentrated lighting, effective lighting is possible because the illumination intensity on the surface of the lighted subject was high. In performance halls or studios of about 6 [m] height, there is no problem of illumination intensity in LED 144 [W] illuminator. Therefore, it is possible to replace the existing tungsten halogen 1 [KW] illuminator one to one.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.1
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• pp.153-160
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• 2003

The purpose of study was to evaluate the effects of the $CO_2$ laser irradiation on demineralization inhibition and rehardening of human primary tooth enamel by laser fluoresecence measurement. Enamel specimens were made from the human primary teeth. The center spots of the specimens about 2 mm diameter were irradiated by $CO_2$ laser at the conditions of focused continuous or defocused pulsed, 3 or 6 W, for 4 seconds, before or after the demineralization by Coca-Cola for 24 hours at $37^{\circ}C$. The Diagnodent was used to measure the degree of demineralization and rehardening. There was no significant difference between focused continuous and defocused pulsed irradiation. 6W irradiation inhibited the demineralization but 3W did not. 6W irradiation rehardened the demineralized enamel but 3W did partially. The color of enamel was changed to brown to black after 6W irradiation but 3W caused no color change. $CO_2$ laser irradiation showed the effects on demineralization inhibition and rehardening of human priamary tooth enamel, and the laser fluoresecence measurement technique seemed to be a valid evaluation method.