• Korean Institute of Interior Design Journal
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• no.17
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• pp.60-64
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• 1998

The results of simulation on greenery ratio using CG are as follows: arrangement type of optimal condition and greenery ratio were summarized as below as dispersion type and 5% ratio greenery for 20 pairs of assessment items and these assessment items were classified into 5 factors as a result of factor analysis,. These factors were Harmony Animation Atmosphere texture Peculiarity. Verification results of factors differences according to each condition can be. there was no apparent difference among factors in accordance with gender, In case of arrangement type dispersion type was higher than concentration type in all factors. Based on the above results dispersion type was assessed higher than concentration type the most suitable condition of Harmony Factor was 5% dispersion type Animation Factor was 5% dispersion type Animation Factor was 7% dispersion type Atmosphere Factor was 10% dispersion type Texture Factor was 5% concentration type and $\ulcorner$Peculiarity Factor$\lrcorner$was 7% concentration type.

• Advances in Energy Research
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• v.8 no.4
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• pp.265-273
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• 2022

In this study, a product gas yield and carbon conversion were measured during the coal pyrolysis. The pyrolysis process occurred under two different atmospheres such as subcritical (45 bar, 10℃) and supercritical CO₂ condition (80 bar, 35℃). Under the same pressure (80 bar), the atmosphere temperature increased from 35℃ to 45℃ to further examine temperature effect on the pyrolysis at supercritical CO₂ condition. For all three cases, a power input supplied to heating wire placed below coal bed was controlled to make coal bed temperature constant. The phase change of CO₂ atmosphere and subsequent pyrolysis behaviors of coal bed were observed using high-resolution camcorder. The pressure and temperature in the reactor were controlled by a CO₂ pump and heater. Then, the coal bed was heated by wire heater to proceed the pyrolysis under supercritical CO₂ condition.

• Journal of the Korean earth science society
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• v.30 no.5
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• pp.630-645
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• 2009

The tropopause fold event that took place on January 1, 1997 over mid-region on the Korean Peninsula is examined by means of a numerical simulation based on a Mesoscale Model (MM5). The purpose of this paper is to investigate the effects of moisture in reinforcing a tropopause fold linked to an explosive cyclone. Two types of simulations were carried out; 1) simulations for moist conditions in which full physical and dynamic processes are considered and 2) simulations for dry conditions in which cumulus parameterization and cloud microphysics process are excluded. The results of the moist condition simulations demonstrate that the intensity of the central pressure of the cyclone was overestimated compared with the observed values and that the location of the center and the pressure deepening rates (-17 hPa/12 hr) complied with the observed values. The potential vorticity (PV) anomaly on the isentropic surface at 305 K continued to move in a southeast direction on January 1, 1997 and thus created a single tube of tropopause fold covering the northern and the middle area of the Korean Peninsula and reaching the ground surface at 0300 UTC and 0600 UTC. The results of the dry condition simulations show that the tropopause descended to 500 and 670 hPa in 0300 and 0600 UTC, respectively at the same location for the moist condition simulation; however, there was no deep tropopause fold observed. A comparison of the simulated data between the moist and the dry conditions suggests that a deep tropopause fold should happen when there is sufficient moist in the atmosphere and significantly large PV in the lower atmosphere pulls down the upper atmosphere rather than when the tropopause descends itself due to dynamic causes. Thus, it is estimated that moisture in the atmosphere should have played a crucial role in a deep tropopause fold process.

• Journal of the East Asian Society of Dietary Life
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• v.3 no.2
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• pp.99-106
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• 1993

The aim of this study is to elevate the efficiency of salting with low salt concentration in order to improve the quality of salted Chinese cabbage. The efficiency of salting was tested with various sub-atmosphere(760mmHg to 0mmHg), temperature(20$^{\circ}C$ and 30$^{\circ}C$), and concentration of salt(3%, 5% and 10%). The salting efficiency was estimated by amounts of juice, calcium elution, sodium penetration and the state of tissue. The amunts of juice eleuted from Chinese cabbage was increased significantly with the decrease of atmosphere and the time to reach the highest amounts was reduced. This tendency was promoted, with increase of salinigy(from 3% to 10%)and the increase of temperature(more juice at 30$^{\circ}C$ than 20$^{\circ}C$). The amounts of eluted calcium from Chinese cabbage tissue during salting under sub-atmosphere was directly proportional to amounts of juice and was inversely proportional to penetrated sodium. The salting time was reduced with elevation of sub-atmosphere. It was desirable to take between 5.5 and 9 hours to salt under the condition of 3% of salting, 20$^{\circ}C$, and 560-0mmHg. It took between 4.4 and 5 hours under 5% of salt and between 4 and 4.5 hours under 10% of salt. However, it was undesirable because the drying phenomenon and the transparency of tissue appeared under 30$^{\circ}C$ and 160-0mmHg.

• The Korean Journal of Ceramics
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• v.6 no.4
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• pp.396-400
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• 2000

Dielectric and piezoelectric properties of Pb$_0.9$La$_0.1$TiO$_3$ ceramics were investigated as a function of grain size. Sintering atmosphere was controlled with changing the kind of atmospheric powder and its amount. It was confirmed that dielectric and piezoelectric of Pb$_0.9$La$_0.1$TiO$_3$ were strongly influenced by the sintering atmosphere. Relative dielectric constant of Pb$_0.9$La$_0.1$TiO$_3$ which was sintered in PbO-deficient atmosphere made by Pb$_0.9$La$_0.1$TiO$_3$ powder, increased with the grain size. However, the dielectric constant of the samples sintered in the PbO-sufficient atmosphere made by PbZrO$_3$ powder was slightly decreased with the grain size. Piezoelectric d$_33$ constant of Pb$_0.9$La$_0.1$TiO$_3$ also showed a different trend, depending on the sintering atmosphere. It was almost constant in the range of grain size of 1.3~2.3 $\mu$m when the samples were sintered in the PbO-sufficient atmosphere, while it intensively decreased with the grain size in the case of the PbO-deficient condition.

• Journal of the Korean institute of surface engineering
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• v.55 no.4
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• pp.215-221
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• 2022

In the present work, copper oxide thin films were formed by heat-treatment method with different temperatures and atmosphere, e.g., at 200 ~ 400 ℃; in air and Ar atmosphere. The morphological, electrical and optical properties of the thermally fabricated Cu oxide films were analyzed by SEM, XRD, and UV-VIS spectrometer. Thereafter, photoelectrochemical properties of the thermal copper oxide films were analyzed under solar light (AM 1.5, 100 mW/cm²). Conclusively, the highest photocurrent was obtained with Cu₂O formed under the optimum annealing condition at 300 ℃ in air atmosphere. In addition, EIS results of Cu oxide formed in air atmosphere showed relatively low resistance and long electron life-time compared with Cu Oxide fabricated in Ar atmosphere at the same temperature. This is because heat-treatment in Ar atmosphere could not form Cu₂O due to lack of oxygen, and thermally formed CuO at high temperature suppressed stability and conductivity of the Cu oxide.

• Journal of the Korean Ceramic Society
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• v.37 no.1
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• pp.1-5
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• 2000

Cathodoluminescence(CL) properties of ZnO:Zn green phosphor were investigated. ZnO:Zn phosphor was synthesized by varying reducing agents and firing temperatures. ZnS, charcoal and 5% H2 gas mixed with 95% N2 gas(5H2-95N2) were used as the reducing agent and atmosphere. The highest CL intensity of ZnO:Zn phosphor was observed under the condition of 5H2-95N2 atmosphere and firing temperature of 90$0^{\circ}C$ for 1h. Charocal and ZnO as reducing agents in the syntehsis of ZnO:Zn phosphor exhibited about 60% and 40%, respectively, of the CL intensity obtained with 5H2-95N2 atmosphere.

• Restorative Dentistry and Endodontics
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• v.25 no.2
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• pp.262-271
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• 2000

The purpose of this study was to estimate shear bond strength according to difference in Targis surface treatment and storage condition. 140 non-carious extracted human molars and Targis D210(Ivoclar, Liechtenstein) were used in the present study and were divided into 7 experimental groups respectively according to surface treatment of Targis. Group 1 ; No treatment, Group 2 ; $50{\mu}m$ aluminium oxide blasting, Group 3 ; 4% HF etching for 3 minutes, Group 4 ; 4% HF etching after blasting, Group 5 ; silane treatment after blasting, Group 6 ; silane treatment after 4% HF etching, Group 7 ; silane treatment after blasting and 4% HF etching. In Each group, one half of 20 specimens was stored in distilled water at $37^{\circ}C$ for 24 hours and the other half was stored at atmosphere for 24 hours respectively. Dentin surface was etched with 10% $H_3PO_4$ for 15 seconds and luting cement(Variolink II, Vivadent, Liechtenstein) was applied by manufacturer's recommendation. Shear bond strength for each group was then measured. To examine the failure patterns after shear bond test and to observe the change after surface treatment of Targis. Specimens were fabricated and observed under the SEM. Statistical analysis was performed by One Way ANOVA test and t-test. The results were as follows ; 1. The shear bond strength of the groups stored in water significantly lower than that of groups stored at atmosphere (P<0.05). 2. There was no significant difference in shear bond strength in groups stored in water (P>0.05). 3. The shear bond strength without surface treatment of Targis were lowest among all experimental groups in atmosphere condition(P<0.05). 4. There was no significant difference in bond strength between groups using the silane or not(P>0.05). 5. The groups treated by blasting, hydrofluoric acid and silane sequentially showed highest bond strength than that of other groups in atmosphere condition, but there was no significant difference(P>0.05). 6 The proportions of the specimens showing the mixed fracture failure were 20% in HF etching group and blasting + HF group, 40% in blasting + HF + silane group in atmosphere condition. All the specimens stored in water showed adhesive fracture failure.

• Journal of the Korea Institute of Military Science and Technology
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• v.11 no.5
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• pp.84-91
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• 2008

The spectral radiance received by a remote sensor at a given temperature and wavelength region is consisted of the self-emitted component directly from the object surface, the reflected component of the solar irradiation at the object surface, and the scattered component by the atmosphere without ever reaching the object surface. The IR image of a ship is mainly affected by location, meteorological condition(atmosphere temperature, wind direction and velocity, humidity etc.), atmospheric transmittance, solar position and ship surface temperature etc. Computer simulations for prediction of the IR signatures of ships are very useful to examine the effects of various meteorological conditions. In this paper, we have acquired the IR signature for different meteorological conditions by using two different computer programs. The numerical results show that the IR image contrast as compared to the background sea considering the atmosphere temperature and wind velocity.

• Journal of the Korean Ceramic Society
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• v.37 no.7
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• pp.726-729
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• 2000

The entitled report revealed that ZnO phosphor samples treated at different temperatures under a given reduction atmosphere show the radiation brightness increase with increase of temperature up to about 900$^{\circ}C$ but become decreasing beyond the temperature. The brightness deterioration with curing temperature at higher temperatures was explained by the decrease of excess zinc ions resulted from their evaporation. The comments will open possibility for different discussions on the experimental result by introducing numerical relationships between the concentration of the native defects and the curing condition.