• Journal of the Korean Society of Clothing and Textiles
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• v.10 no.2
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• pp.1-9
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• 1986

To study the effects of surface structure of fiber on the decrement of fatty soil removal at high temperature, the following variables were selected: controled and alkali-treated P.E.T.(polyester) fabrics and chopped fibers as substrates to estimate the detergencies, different aging methods of soiled substrates, and different washing temperatures and surfactant solutions. Radiotagged tripalmitin was used as soil and the detergency was estimated by means of liquid scintillation counting method. The results were as following: The surface of the fiber became rough with many grooves and the hydrophilicity of the fiber was increased and the structure of the fabric became loose by alkali treatment. While the detergency of alkali-treated P.E.T. fabric was better than that of controled P. E. T. fabric, there was no significant differences between the detergencies of controled and alkali-treated chopped fibers. These results indicate that the increment of detergency of alkali-treated P.E.T. fabric is mainly resulted from the changes of fabric structure and the improved hydrophilicity of fiber by alkai treatment. The detergency of tripalmitin was increased with elevating temp. below the m.p. of tripalmitin, was decreased around the m.p., and again was increased above the m.p ..It is considered that the decrement of detergency around the m.p. is due to the diffusion of molten tripalmitin into the grooves on fiber surface, the inner part of fiber, and between fibers. When controled and alkali-treated soiled fabrics and soiled chopped fibers were washed in the distilled water and in the Na-DBS solution respectively, below $60^{\circ}C$ detergencies of alkali-treated fabrics and chopped fibers were improved. However above $60^{\circ}C$ this result was reversed. Therefore these results are regarded as the effects of grooves on fiber surface at high temp. and improved hydrophilicity at low temp. by alkali treatment. When controled and alkali-treated soiled fabrics and soiled chopped fibers were hot-aged before washing, the detergencies of both species were decreased generally. Because the soil was diffused into the grooves on fiber surface, the inner part of fiber, and between fibers during hot-aging. The detergencies of hot-aged species were also decreased above certain temp.. These results suggest that the decrement of detergency at high temp. be resulted not only from the diffusion of soil into the grooves on fiber surface, the inner part of fiber, and between fibers, but also from the characteristics of surfactant solutions.

• Journal of Korean Society on Water Environment
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• v.35 no.3
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• pp.257-270
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• 2019

Followingthe Four Rivers Project, cyanobacterial blooms have been frequently observed in the upstream of the installed weirs. The aim of this study was to characterize the major environmental factors that are associated with the cyanobacteria dominance in Baekje Weir (Geum River) and Juksan Weir (Youngsan River) based on intensive experiments and systematic data mining methods. The factors related to the cyanobacteria dominance include7-days cumulative rainfall (APRCP7), 7-days averaged flow (Q7day), water temperature (Temp), stratification strength (${\Delta}T$), electronic conductivity (EC), DO, pH, $NO_3-N$, $NH_3-N$, TN, TP, $PO_4-P$, Chl-a, Fe, BOD, COD, TOC, and $SiO_2$. The most highly correlatedfactors to the dominant cyanobacteria were found to be EC, Temp, Q7day, $PO_4-P$ in theBaekje Weir. On the other hand, those dominant in the Juksan Weir were ${\Delta}T$, TOC, Temp, EC and TN. The EC showed a strong correlation with cyanobacteria dominance in both weirs because a high EC represents a persisted low flow condition. The cyanobacteria dominance was as high as 56 % when the EC was equal or greater than $418{\mu}S/cm$ in Baekje Weir. It was as high as 63% when the ${\Delta}T{\geq}2.1^{\circ}C$ in the Juksan Weir. However, nutrients showed a minor correlation with cyanobacteria dominance in both weirs. The results suggest that the cyanobacteria dominate in astate where the water flow rate is low, water temperature is high and thermal stratification is strengthened. Therefore, the improvement of flow regimes is the most important to prevent persistent thermal stratification and formation of cyanobacteria bloom in theBaekje and JuksanWeirs.

• Proceedings of the KWS Conference
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• 1990.11a
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• pp.34-35
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• 1990

• The Journal of Korean Academy of Prosthodontics
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• v.46 no.6
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• pp.639-643
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• 2008

STATEMENT OF PROBLEM: The degree of conversion may influence the ultimate mechanical and physical properties of provisional crown and fixed partial denture materials. The high levels of the unreacted residual monomer may cause deleterious effect on the properties. PURPOSE: The purpose of this study was to measure the degree of conversion of bis-acrylic based provisional crown and fixed partial denture materials by using an infrared spectroscopic method. MATERIAL AND METHODS: Chemically activated three bis-acrylic based provisional crown and fixed partial denture materials, LuxaTemp [DMG, Hamburg, Germany], fast set TemPhase [Kerr, Orange, CA, USA] and Protemp 3 Garant [3M-ESPE, St Paul, MN, USA], were investigated by Fourier transform infrared spectrometry (FTIR). The FTIR spectra of the materials tested were immediately obtained after mixing. The specimens were stored under dry conditions and at $23^{\circ}C$ for 24 hours, and then the spectra of the materials were also obtained. The degree of conversion (%) was calculated from the spectrum of the absorbance between the aliphatic double bond at 1637 $cm^{-1}$ and the aromatic double bond at 1608 $cm^{-1}$ using the baseline method. The data were statistically analyzed using one-way ANOVA and the multiple comparison Scheffe test at the significance level of 0.05. RESULTS: The mean value and standard deviation of the degree of conversion were 52.5 % ${\pm}$ 1.1 %, 50.3 % ${\pm}$ 0.8 %, and 42.3 % ${\pm}$ 4.9 % for LuxaTemp, Protemp 3 Garant and fast set TemPhase, respectively. There was no significant difference between LuxaTemp and Protemp 3 Garant, whereas there was a statistically difference between Protemp 3 Garant and fast set TemPhase, and LuxaTemp and fast set TemPhase (P < .05). CONCLUSION: The degree of conversion of fast set TemPhase was significantly lower than those of the others. The degree of conversion may be correlated with the rate of polymerization.

• Applied Biological Chemistry
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• v.34 no.4
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• pp.339-343
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• 1991

The objective of this study was to evalute changes of $CO_2$ pressure, pH, precipitation, brix, free sugar, colority, crude saponin and ginsenoside contents of Ginseng Drink Product for ten months at different temperatures $(room\;temp.,\;35^{\circ}C$ and $50^{\circ}C)$. The results are as follows : $CO_2$ pressure was decreased after nine month storage at room temp., six months at $35^{\circ}C$ and three months at $50^{\circ}C$. pH and brix nearly constant at various storage temperatures and periods. Precipitation was appeared after five months storage at room temp., two months at $35^{\circ}C$ and one month at $50^{\circ}C$. Sucrose content was decrease, while glucose and fructose contents were increased at high temperature and long period of stroage. Colority and panaxatrial(PT) saponin contents were increased, while panaxadiol(PD) saponin was increased at high temperature and long period of stroage.

• 한국태양에너지학회:학술대회논문집
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• 2009.11a
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• pp.259-264
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• 2009

Most of the fossil power plants firing lower grade coals are challenged with maintaining good combustion conditions while maximizing generation and minimizing emissions. In many cases significant derate, availability losses and increase in unburned carbon levels can be attributed to poor combustion conditions as a result of poorly controlled local fuel and air distribution within the boiler furnace. The poor combustion conditions are directly related to the gas flow deviation in upper furnace and convection tube-bank but a less reported issue related to in large-scale oppose wall fired boilers. In order to develop a on-line combustion monitoring system and suggest an alternative heat flux estimation method at tube bank, which is very useful information for boiler design tool and blower optimizing system, field test was conducted at operating power boiler. During the field test the exhaust gases' temperature and tube metal temperature were monitored by using a spatially distributed sensors grid which located in the boiler's high temperature vestibule region. At these locations. the flue gas flow is still significantly stratified, and air in-leakage is minimal which enables tracing of poor combustion zones to specific burners and over-fire air ports. Test results showed that the flue gas monitoring method is more proper than metal temperature distribution monitoring for real time combustion monitoring because tube metal temp. distribution monitoring method is related to so many variables such as flue gas, internal flow unbalance, spray etc., Heat flux estimation at the tube bank with flue gas temp. and metal temp. data can be alternative method when tube drilling type sensor can't able to use.

• Journal of Convergence for Information Technology
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• v.11 no.7
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• pp.298-306
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• 2021

The purpose of this study was to examine the occupational risk factors that affect oral symptoms in hospital facility workers. This study surveyed 627 hospital facility temp·contract workers in the metropolitan area from November 17, 2020 to May 20, 2021. The results of the study indicate that oral symptoms were higher among workers with high risk of musculoskeletal disorders and injuries. Also, symptoms of oral mucosa, temporomandibular joint disorder, and dry mouth were high in the areas of job insecurity and organizational injustice. As the occupational risk factors and occupational stress of workers increased, the risk of oral symptoms increased. In the future, this study can be used as basic data for improving oral health policies to better the oral health of hospital facility workers.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2008.05a
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• pp.23-29
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• 2008

- High Density Plasma Source-CCP-Dual/Triple, RF Frequency Control - Radical/Flux Analysis - Low Pressure Process - Chamber Design (Process gap/Wall gap) - Chamber Temp. Control. - ESC Dielectric Materials - Uniform Gas Injection

• Korean Journal of Materials Research
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• v.9 no.12
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• pp.1176-1180
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• 1999

The adhesion strength and high temperature/high humidity reliability of polyetherimide (PEI) adhesive on silicon wafer after being treated by each reactive ion etching (RIE) Aluminum (Al)-chelate adhesion promoter were investigated. 180$^{\circ}$ peel test and <85$^{\circ}C$ 85%> humidity test were performed for the initial adhesion strength and high temperature/high humidity reliability, respectively. For investigating surface effect scanning electron microscope (SEM), atomic force microscope (AFM), deionized (DI)-water contact angle studies were carried out. To investigate RIE effect, PEI was treated with $^O_2$ RIE, and then laminated. The initial peel strength increased slightly from 1.6 kg/cm for the first 2 minutes, and then decreased. High temp/high humid resistance decreased rapidly by RIE etching. RIE treatment on PEI affected on both of roughness and hydrophilicity increase. Aluminum-chelate adhesion promoter was coated by spinning on silicon wafer. The initial peel strength showed no effect of adhesion promoter treatment, but high temp/high humidity resistance increased remarkably. Al-chelate adhesion promoter did not affect the roughness but increased hydrophilicity.

• KIEAE Journal
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• v.11 no.6
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• pp.101-108
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• 2011

The weather data has important role for performative building design. If the data location is close to building site, the result of performative design can be accurate. The data which have used nowadays in Korea are from U.S. Department of Energy (DOE) and Korea Solar Energy Society (KSES) but they cover only several locations in Korea which are 4 in DOE and 11 in KSES and there are opinions which it could be served building design efficiently even if the data are not enough. However the weather data for micro-climate are exist which are Green Building Studio Virtual Weather Station (GBS VWS) and Meteonorm weather data. Each weather data has different generation methods which are TMY2, TRY, MM5, and extrapolation. In this research, the weather date for climate are compared with DOE and KSES to check correlation. The result shows the value of correlation in Dry Bulb Temp. and Dew Point Temp. is around 0.9 so they have high correlation in both but in Wind Speed case the correlation(around 0.2) is not exist. In overall result, the data has correlation with DOE and KSES as the value of correlation 0.648 of GBS VW and 0.656 of Meteonorm. Even if the correlation value is not high enough, the patterns of difference in each weather element are similar in scatter plot.