• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.5
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• pp.366-371
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• 2012

In this paper, fabricated by MEMS uncooled micro-bolometer detector for the study in the infrared sensitivity enhancement. Absorption layer SiOx-Metal series MDTF (metal-dielectric thin film) by high absorption rate and has a high thermal coefficient of resistance, low noise characteristics were implemented. Then MDTF were made in a vacuum deposition method. And MDTF for the analysis of the physical properties of silicon wafers were fabricated, TCR (temperature coefficient of resistance) value was made in order to measure the glass wafer and FT-IR (Fourier Transform Infrared spectroscopy) values were made in order to measure the germanium window. The analyzed results of MDTF -3 [%/K] has more characteristics of the TCR. And 8~12 um wavelength region close to 70% in the absorption characteristic.

• YAKHAK HOEJI
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• v.23 no.2
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• pp.81-94
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• 1979

Rifampicin-polyvinylpyrrolidone coprecipitates were prepared by the solvent method to increase the solubility and dissolution rate, thereby improving absorption of rifampicin. It was found that the solubility and dissolution rate were greater with the 1 : 5 (w/w) coprecipitate than with the pure drug, physical mixtures or coprecipitates of any other ratio of the two components. The blood concentration data in non-fasted rats showed that the extent of absorption of rifampicin were significantly enhanced following the oral administration of the 1 : 5 coprecipitate; The area under the serum concentration curve (0-8hr) was 1.3 times greater with the 1 : 5 coprecipitate than with the pure drug. The blood concentration reached its peak (4. 38$\pm$1.36mcg/ml) within two hours in the case of oral administration of the 1 : 5 coprecipitate and, on the other hand, it reached the maximum (3.77$\pm$0.90mcg/ml) after four hours of oral administration of the pure drug. It was observed that there was no significant difference between the 1 : 5 coprecipitate and the pure drug in the extent and rate of absorption of rifampicin when fasted rats were used. When the 1 : 5 coprecipitate was orally administered to human subjects 20 minutes after meal, it was found that the blood concentration reached the maximum after one hour; in the case of the pure drug, it reached its peak after four hours.

• Journal of architectural history
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• v.22 no.6
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• pp.59-66
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• 2013

This study progressed an investigation on the cause of the efflorescence phenomenon of bricks in Suwon Hwaseong Fortress, which is designated as a UNESCO World Heritage by using diverse scientific analyses. The samples were taken in Hwaseong and analyzed using XRD and SEM-EDS for the material identification of efflorescence. We observed under a polarizing microscope and measured absorption factors for the basic investigation for traditional bricks. As a result of material identification, soluble salt($Na_2SO_4$, $KNO_3$) and insoluble salt($CaCO_3$) were detected. There was no big difference between original bricks and repaired bricks under the polarizing microscope. However, in terms of the water absorption rate, bricks which were used for repair nowadays showed low water absorption rate(1%). In conclusion, soluble salt and insoluble salt appeared due to an effect of an air pollution and joint mortar. Soluble salt was removed in the rainy season, but insoluble salt was not removed. As a result of the efficiency and safety tests for chemicals removing efflorescence, chemical E is likely to be the suitable chemicals for the efflorescence phenomenon of traditional bricks in Suwon Hwaseong Fortress. In the future, consideration whether the use of lime is available or not should be studied through comprehensive researches including repair work, construction work and the environment factor with lime. Also, physical, chemical identifications of repairing bricks will be required.

• Clean Technology
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• v.7 no.2
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• pp.151-159
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• 2001

Mathematical modeling and numerical simulation studies have been conducted for a falling film type absorber of the ammonia absorption heat pump. A rigorous absorber model has been developed by considering temperature effects on physical properties and its predictability proved far superior to that of existing models, which has been confirmed by the experimental data. Using the developed model, effects of cooling water condition - temperature and flow rate - on the efficiency of absorber has been examined. As the result of simulation, the efficiency of absorber has increased as the cooling water temperature has decreased and flow rate has increased.

• Transactions of the Korean Society of Mechanical Engineers
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• v.13 no.2
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• pp.265-270
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• 1989

The present study considers the thermal structure variation in a porous medium caused by changing the most important radiative property of porous medium, absorption coefficient, as well as altering the physical dimension of porous medium and the equivalence ratio of premixed gas mixture. The radiation model was introduced as an unsteady differential form using the two-flux gray radiation model. The role of the conductive heat transfer through both gas phase and porous medium was found to be almost insignificant compared with that of the radiative heat transfer. The reaction zone shifted upstream and the flame thickness decreased as either the geometrical length of porous medium increased or the absorption coefficient decreased.

• Journal of the Korean Ceramic Society
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• v.43 no.5 s.288
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• pp.277-283
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• 2006

A porous material with a surface layer was fabricated from glass abrasive sludge and expanding agents. The glass abrasive sludges were mixed with expanding agents and compacted into precursors. These precursors were sintered in the range of $700-900^{\circ}C$ for 20 min. The sintered porous materials had a surface layer with smaller pores and inner parts with larger pores. The surface layer and closed pores controlled water absorption. As the expanding agent fraction and the sintering temperature increased, the porosity and pore size increased. The porous materials with $Fe_2O_3$ and graphite as the expanding agents had a low absorption ratio of about 3% or lower while the porous material with $CaCO_3$ as the expanding agent had a higher absorption ratio and more open pores.

• Journal of the Korean Applied Science and Technology
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• v.2 no.2
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• pp.47-53
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• 1985

Correlation among the wax-pigment composites which is base vehicles for the crepas was investigated in terms of fadeness. The base wax synthesized and pigments are compounded with petroleum lubricant and exposed under carbon arc individually. The yellowing phenomenon was appeared on the reference papers coated with the spindle oil which was then exposed. The papers were again extracted with distilled water and pH of them were ranged between 6.2-6.5. Color difference from Adam-Nickerson equation, ${\vartriangle}E$ of base wax is 0.15 and that of spindle oil are varied from 0.66 to 15.62. Since the main components of the petroleum lubricant are aromatic hydrocarbons which have absorptions characteric of UV ranging from 240 to 280 nm, fadeness characteristics of the composites are largely depend upon the change of molecular structure of spindle oil by absorbing UV. Thus the spindle oil having the following physical properties has the better resistance of fadness and is recommended to use in compounding the base wax-pigment composites: ${\cdot}$ main component: paraffinic hydrocarbon ${\cdot}$ pour point: below - $15^{\circ}C$ ${\cdot}$ UV absorption characteristics: ${\lambda}max.$ : 268-290nm ${\cdot}$ absorbancy: below 0.1(0.03ml of sample/50ml of $CHCl_3$)

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.533-536
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• 2006

A light-weight aggregate with a surface layer was fabricated using glass abrasive sludge and expanding agents. The glass abrasive sludges were mixed with expanding agents ($Fe_2O_3,\;graphite,\;CaCO_3$) and formed into precursors. These precursors were sintered in the range of $700-900^{\circ}C$ for 20min. The sintered light-weight aggregate had a surface layer with smaller pores and an inner region with larger pores. The surface layer and pores controlled the water absorption ratio and physical properties. As the expanding agent fraction and the sintering temperature increased, the porosity and pore size increased. The light-weight aggregate with $Fe_2O_3$ and graphite as the expanding agents had a low water absorption ratio while the porous material with $CaCO_3$ as the expanding agent had a higher water absorption ratio and more open pores.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.05b
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• pp.120-124
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• 2004

The protection performance and energy absorption capability are important for both MOAs for distribution lines and MOAs for high voltage systems, therefore the manufacturing technique of ZnO varistor elements with high ability against surge impacts is great important for high voltage systems. But until now ZnO varistors for low voltage class have been developed in Korea, ZnO varistors with the rate discharge current of 5, 10kA class for high voltage systems depend on an import from advanced countries, such as Japan or U.S.A, which have developed its in the late 1980s. So in the aspect of taking independent technique the development of ZnO varistors with the rate discharge current of 5, 10kA class for high voltage systems is important. In this research project ZnO varistor elements with diameters of 35mm and 70mm for the rate discharge current of 5, 10kA class for high voltage systems are manufactured, then various chemical composition and processing variables affected the electrical and the physical characteristics of these ZnO varistors are investigated.

• Textile Coloration and Finishing
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• v.14 no.5
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• pp.268-276
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• 2002

Poly(trimethylene terephthalate)(PTT) and Poly(ethylene terephthalate)(PET) fibers were annealed at various temperatures ranging from $100^\circ{C}$ to $230^\circ{C}$ for 10 min under tension and tension free. Dyeing rates and absorption isotherms of both fibers were obtained with C.I. Disperse Red 60 at 100, 120 and $130^\circ{C}$ in water system. Also X-ray diffraction pattern, moisture regain and water absorption were investigated. The dyeing rate of PTT fiber is faster than PET fiber, and dyeing of PTT fiber begin at lower temperature compared to PET fiber. The absorption isotherms from both fibers with disperse dye we nearly linear up to the saturation dye uptake, which increase with dyeing temperature. Equilibrium dye uptake of PTT fiber annealed under tension above $180^\circ{C}$ was remarkably decreased because of a changes in the fine structure of fiber. The intensities of X-ray diffraction peaks of both annealed fibers were increased with increasing in annealed temperature. The reflections observed at $2\theta$=$15.8^\circ$, $24^\circ$ and $25.2^\circ$ were assigned reflection of crystal at the planes of (010), $(1\bar02,\;\bar112),\;and\;(\bar13,\; \bar113)$ respectively, and the peak became sharp with heat setting temperature.