• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.1
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• pp.154-161
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• 2001

We have treated polyester fabric with $CF_4,\;C_2F_6,\;SF_6\;and\;C_3F_6$ glow discharge plasmas to develop functional fabrics which preserve moisture transportation and water proofing nature. Modified properties were evaluated by water vapor permeation rate and breakthrough water pressure. The change of surface morphology was observed by SEM. Fiber interstice of the plasma treated fabric was calculated as $0.32{\mu}{\textrm}{m}$, and this value was sufficiently ideal as water repellent material. The moisture transportation of ${CF_4}-treated$ fabric was good as much as untreated fabric, and those of $C_2$F(sub)6-treated, SF(sub)6-treated fabrics were reduced by 1~3%, and that of ${C_3F_6}-treated$ fabric was reduced by 15%. The best treatment condition were 0.06 torr 120 seconds in $CF_4$, 0.05 torr 30 seconds in $SF_6$, 0.08~0.15 torr 90 seconds in $SF_6$ and 0.1 torr 45 seconds in $C_3F_6$ respectively. The grade of moisture transportation effect was $CF_4>C_2F_6>SF_6>>C_3F_6$, and water proofing effect was $C_2F_6{\approx}CF_4>C_3F_6>SF_6$. It was observed by SEM that the thin film was formed on the surface of the treated substrate by the fluorocarbon plasma treatment.

• Structural Monitoring and Maintenance
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• v.10 no.2
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• pp.155-174
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• 2023

High performance concrete (HPC) has been extensively used in thin overlay for repair purpose due to its excellent strength and durability. This paper presents an experiment, where the sensor-instrumented HPC overlays have been followed by dynamic strain and moisture content monitoring for 1 year, under normal traffic. The vibrating wire and soil moisture sensors were embedded in overlay before construction. Four given HPC mixes (2 original mixes and their shrinkage-modified mixes) were used for overlays to contrast the strain and moisture results. A calibration method to accurately measure the moisture content for a given concrete mixture using soil moisture sensor was established. The monitoring results indicated that the modified mixes performed much better than the original mixes in shrinkage cracking control. Weather condition and concrete maturity at early age greatly affected the strain in concrete. The strain in HPC overlay was primarily in longitudinal direction, leading to transverse cracks. Additionally, the most moisture loss in concrete occurred at early age. Its rate was very dependent on weather. After one year, cracking survey was carried out by vision to verify the strain direction and no cracks observed in shrinkage modified mixes.

• Clean Technology
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• v.22 no.4
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• pp.299-307
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• 2016

These days, coal is one of the most important energy resources used for transportation, industry, and electricity. There are two types of coal: high-rank and low-rank. Low-rank coal has a low calorific value and contains large amounts of useless moisture. The quality of low-rank coal can be increased by simple drying technology and it needs to be stabilized by hydrocarbons (e.g. palm acid oil, PAO) to prevent spontaneous combustion and moisture re-adsorption. Spontaneous combustion becomes a major problem during coal mining, storage, and transportation. It can involve the loss of life, property, and economic value; reduce the quality of the coal; and increase greenhouse gas emissions. Besides spontaneous combustion, moisture re-adsorption also leads to a decrease in quality of the coal due to its lower heating value. In this work, PAO was used for additive to stabilize the upgraded coal. The objectives of the experiments were to determine the stabilization characteristic of coal by analyzing the behavior of upgraded coal by drying and PAO addition regarding crossing-point temperature of coal, the moisture behavior of briquette coal, and thermal decomposition behavior of coal.

• Corrosion Science and Technology
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• v.4 no.5
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• pp.207-210
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• 2005

Coating performance of various coating systems including chlorinated rubber and epoxy/urethane used most for steel structures of highway in Korea, was evaluated by exposing test specimen to complex deterioration factors such as ultraviolet ray, moisture, freeze-thaw cycle and salt. Deteriorated specimens were evaluated by chalking and rust grades according to ASTM, and measurement of color differences and adhesion. In overall coating performances such as corrosion resistance, photochemical stability, and adhesion, ceramic/ urethane, moisture-curable urethane/ urethane, etc. were superior. As for other coating materials tested in this study, superior materials against certain deterioration factors may be inferior against other factors. Accordingly, in order to select suitable maintenance coating materials for the use, it is thought that investigation of suitability through experiment should precede selection of materials, especially for unusual coatings or paints.

• Journal of The Korean Society of Agricultural Engineers
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• v.57 no.4
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• pp.61-71
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• 2015

Quantitative variability of AMSR2 (Advanced Microwave Scanning Radiometer 2) soil moisture data shows that the remotely sensed soil moisture is underestimated during Spring and Winter seasons and is overestimated during Summer and Fall seasons. Therefore the bias correction of the remotely sensed data is essential for the purpose of water resource management. To enhance their applicability, the bias of AMSR2 soil moisture data was corrected using ground observation data at Cheorwon Chuncheon, Suwon, Cheongju, Jeonju, and Jinju sites. Test statistics demonstrated that the correlation coefficient R is improved from 0.107~0.328 to 0.286~0.559 and RMSE is improved from 9.46~14.36 % to 5.38~9.62 %. Bias correction using ground network data improved the applicability of remotely sensed soil moisture data.

• The Korean Journal of Food And Nutrition
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• v.33 no.6
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• pp.666-671
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• 2020

To analyze the quality characteristics of soybean (Glycine max), the approximate analysis, physical properties, mineral and free sugar content of domestic soybean cultivars were analyzed. The moisture content was about 9.15~11.84%. The fat content of Cheonga, Taekwang, and Jinpung cultivars were 17.93~18.37%, which was significantly higher than that of others. Protein content of Cheonga and Seonyu were 36.15~36.70%, significantly higher than that of others. As for the weight and shape of soybeans, the Daewon was the largest allele, and the seed cover ratio was the highest in the Seonyu. In terms of water absorption rate, the Seonyu showed the highest absorption rate at 246.19%, and the Daewon showed the lowest absorption rate. Soaked soybeans had a hardness of 2.80~4.73 kg/㎠, which did not show low hardness in the sample with high moisture absorption. The grinded soybeans showed higher lightness and yellowness values than the raw soybeans, and the redness was decreased. Soybean minerals contained high K, P, Mg, and Ca content. Overall, The Taekwang contained more minerals than others. Stachyose, sucrose, glucose and fructose were detected as free sugars in soybeans. The total free sugar content of Taekwang was the lowest at 3.47%, and the Cheonga (6.80%) was the highest.

• Journal of the Korea Concrete Institute
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• v.16 no.5 s.83
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• pp.725-731
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• 2004

A field test program was conducted for the newly placed concrete pavement of US Interstate Highway 10 between March 26th and 28th, 2003. The test section was located between Van Horn and Sierra Blanca in Hudspeth County approximately 130 km east of El Paso, Texas. The main objective of the test was collecting moisture-related data to validate the models of effective curing thickness, evaporation rate, and moisture-based maturity. Effect of moisture loss on drying shrinkage strain was studied using additional test instrumentation.

• Journal of Integrative Natural Science
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• v.4 no.4
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• pp.298-310
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• 2011

Recently the traffics and transportation hazzards by fog are tremendously Increased. There occurred the greater traffic disaster by Dense Fog of Oct.2006. In this study frequent occurrences of advection fogs centerd over Honam Prov are investigated. Increment of transportation during the Fog period for 1996~2005(decade)are statistically analyzed with Honam Prov.'s fogs. For Honam west coast(Gunsan, Mokpo), inland of Honam(Junju, Gwangju, Suncheon), Honam south coast(Wando, Yepsu), Wind, Dew point, Diff. of air and sea temp. relative humidity are classified between 12 hours before and on time of fog with three Dimensional Analysis System(KLAPS). High frequencies of advection-radiation Fog occurrence in western Coasts except for Suncheon. The application of fog characteristics analyzed by KLAPS for denser fog over the western coast in Fall to Fog prediction and special advisory issues. The advection-radiation fog can occure favorably when the moisture index is less than $2^{\circ}C$, relative humidity is greater than 90%, but the moisture depth is under 1.5 km. In addition when the height of 925 hPa is rising, then fog occurs, but for sinking is disappearing.

• The Korean Journal of Food And Nutrition
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• v.28 no.3
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• pp.493-498
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• 2015

The aim of this study is to investigate the changes in the quality characteristics of cheonggukjang made with germinated soybeans, which is produced by the addition of a smoking process. The L value of smoked cheonggukjang made with germinated soybeans (SCGS) was higher than that of non-smoked cheonggukjang made with non-germinated soybeans (NCNS) and non-smoked cheonggukjang made with germinated soybeans (NCGS). The a value of NCNS was the highest, followed by NCGS and SCGS. The b and ${\Delta}T$ values had a similar tendency compared with the L value. The amino acids in NCGS were significantly decreased compared with NCNS, whereas no remarkable difference in amino acid content was observed between NCGS and SCGS. The moisture content of NCGS ($61.9{\pm}0.9%$) was increased by more than 8% compared with that of NCNS ($53.3{\pm}0.7%$). The moisture content of SCGS was significantly decreased compared with NCGS, whereas the moisture content of SCGS was higher than that of NCNS. The pH of SCGS was significantly the highest, followed by NCGS and NCNS. The viscous substance content of NCGS was significantly increased compared with that of NCNS. No remarkable difference in viscous substance content was observed between NCGS and SCGS. The number of aerobic bacteria in SCGS was significantly decreased compared with NCGS. The levels of total isoflavone in NCNS, NCGS, and SCGS were $1,573.9{\pm}62.5$, $1,759.1{\pm}65.8$, $1,738.0{\pm}68.1mg%$, respectively.

• Geomechanics and Engineering
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• v.23 no.3
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• pp.261-273
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• 2020

This paper presents an efficient method utilizing user-defined computer functional codes to determine the reliability of an embankment slope with spatially varying soil properties in real time. The soils' mechanical properties varied with the soil layers that had different degrees of compaction and moisture content levels. The Latin Hypercube Sampling (LHS) for the degree of compaction and Kriging simulation of moisture content variation were adopted and programmed to predict their spatial distributions, respectively, that were subsequently used to characterize the spatial distribution of the soil shear strengths. The shear strength parameters were then integrated into the Geostudio command file to determine the safety factor of the embankment slope. An explicit metamodal for the performance function, using the Kriging method, was established and coded to efficiently compute the failure probability of slope with varying moisture contents. Sensitivity analysis showed that the proposed method significantly reduced the computational time compared to Monte Carlo simulation. About 300 times LHS Geostudio computations were needed to optimize precision and efficiency in determining the failure probability. The results also revealed that an embankment slope is prone to high failure risk if the degree of compaction is low and the moisture content is high.