• Journal of Korean Society on Water Environment
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• v.22 no.1
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• pp.97-103
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• 2006

Excess sludge treatment and disposal currently represent a rising challenge for domestic or wastewater treatment plants due to economic, environmental and regulation factors. Conventional gravity sedimentation process has been widely used in sludge thickening. The operation method of the process is very simple, but the process requires long detention time for sludge thickening, uses polymers, and shows low sludge thickening efficiency. To solve the problems, we studied on DAF (Dissolved Air Flotation) system. We use bulking sludge of a paper manufacturing plant. The effects of parameters such as SVI (Sludge Volume Index), storage time, initial concentration and wet density of excess sludge were examined. The results showed that the more SVI was low, the more sludge was thickened. As storage time goes by, SVI was increased and thickening performance was deteriorated. In order to improve flotation performance at high concentration, high recycling ratio and pressure did not increase the concentration due to thickening limitation. The addition of 0.8 g/L of loess was increased flotation efficiency of 1.41 times.

• Journal of the Korean Academy of Clinical Electrophysiology
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• v.11 no.1
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• pp.21-29
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• 2013

Purpose : The purpose of this study was to determine the changes in ultrasound imaging of the lower limbs in patients with degenerative osteoarthritis who received a total knee replacement (TKR). Methods : The participants for the study were ten patients who were to receive a total knee replacement. Measurements were taken a total of three times: before receiving a total knee replacement, and one week and two weeks after receiving a total knee replacement. The vastus medialis, rectus femoris muscle, tibialis anterior and gastrocnemius muscle were measured using ultrasound imaging. Results : Muscle thickness of the vastus medialis, rectus femoris muscle, tibialis anterior and gastrocnemius muscle had no significant interaction over time whether surgery was performed or not. White area index (WAI) and density of vastus medialis, rectus femoris muscle, tibialis anterior and gastrocnemius muscle had no significant interaction over time whether surgery was performed or not. Conclusion : In conclusion, lower quality muscles were due to a decrease in muscle fiber and an increase in fat fiber. Therefore, initial physical therapy after total knee replacement should consider this point and be designed appropriately as a therapeutic approach for total knee replacement patients.

• Korean Journal of Clinical Laboratory Science
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• v.44 no.2
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• pp.39-45
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• 2012

The purpose of this study was to determine the association between serum uric acid, abdominal obesity, and waist circumference (WC) in Korean. A total of 208 healthy examinees were examined at Gimcheon Medical Center from July 2011 to December 2011. WC and body mass index (BMI) of subjects were measured as well as blood pressure, fasting blood sugar level, High Density Lipoprotein (HDL) and Low Density Lipoprotein (LDL) cholesterol, C-reactive protein (CRP), triglycerides, and serum uric acid (SUA). In both men (p<0.05) and women (p<0.01), BMI and SUA were significantly correlated with WC. In men, triglycerides (r=0.501, p<0.01) had a positive correlation with WC, and CRP (r=0.442, p<0.01) had a positive correlation with BMI. In women, triglycerides (r=0.470, p<0.01) and CRP (r=0.366, p<0.01) had a positive correlation with WC. Therefore, WC and SUA may be the most effective anthropometric indices of obesity for screening Korean population.

• Journal of Ceramic Processing Research
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• v.22 no.3
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• pp.253-257
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• 2021

Among various thin film encapsulation (TFE) methods, thin films prepared by atomic layer deposition (ALD) have been shown to provide superior protection against the permeation of moisture and oxygen. This technique has numerous of advantages such as excellent uniformity, precise thickness control, and strong adhesion. Therefore, with ozone-based ALD, we conducted the influence of the thickness of aluminum oxide (Al2O3) on moisture barrier properties. From the results of an electrical calcium test, Al2O3 had two distinctly different permeation regimes. Between 10 and 25 nm of Al2O3 thickness, the water vapor transmission rate (WVTR) decreased exponentially from 6.3 × 10-3 to 1.0 × 10-4 g m-2 day-1 (1/60 times). In contrast, as thickness increased from 25 to 100 nm, the WVTR values decreased by only two-thirds, from 1.0 × 10-4 to 6.6 × 10-5 g·m-2·day-1. To better understand the change from an exponential to a sub-exponential regime, defect density and refractive index of Al2O3 were measured. The thickness dependence on defect density and refractive index was analogous with one of moisture barrier performance. These results confirmed the existence of a critical thickness at which the WVTR decreased drastically.

• Journal of Ceramic Processing Research
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• v.23 no.4
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• pp.535-540
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• 2022

Atmospheric pressure plasma (APP) systems operate at atmospheric pressure and low temperatures, eliminating the need forvacuum systems such as vacuum chambers and pumps. In this paper, we studied that silicon dioxide thin films were formedat room temperature (25 oC) and 400 oC by APP processes on silicon wafers. A mixture of hexamethyldisilazane, oxygen,helium, and argon was supplied to the plasma apparatus to form the SiO2 layer. It was observed that a heat insulating layerhaving a thickness of about 22 nm at 25 oC and about 75 nm at 400 oC was formed. Although the surface was clean in samplestreated at 400 oC, small grains were observed in samples processed at room temperature. However, no void or defect in allsamples is observed inside the thin film from the surface. The physical property of the SiO2 thin film carried out by measuringrefractive index and density. The experimental refractive index of silicon dioxide grown by applying heat can be fitted to theSellmeier equation. Also, the film density of the sample at 400 oC using a XRR was observed to be 2.25 g/cm3, similar to thatof the glass, but that of the sample treated at room temp. was very low at 1.68 g/cm3. We also investigated the voltagedependentcurrent change in the oxide material. The SiO2 layer coated at room temperature showed a breakdown electricalfield of 2.5 MV/cm, while oxides deposited at 400 oC showed a characteristic of 9.9 MV/cm.

• Clinical Nutrition Research
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• v.11 no.3
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• pp.194-203
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• 2022

To investigate adipokines (vaspin, omentin-1, adiponectin and leptin) and their correlation with hepatosteatosis degree in obese/overweight (O/O) children. We analyzed adipokine levels of 81 children (49 O/O, [body mass index (BMI) > 95^th] and 32 non-obese (BMI = 5-85^th) admitted to the pediatric outpatient clinic. Serum triglyceride, glucose, low density lipoprotein-cholesterol, total cholesterol, high density lipoprotein-cholesterol, alanine aminotransferase, aspartate aminotransferase (AST), insulin, HbA1c levels and leptin, omentin-1, vaspin, adiponectin levels were studied. O/O children with hepatosteatosis were divided into grades 1, 2 and 3 according to the degree of hepatosteatosis determined by ultrasonography. While AST (p = 0.001), triglyceride (p = 0.006), BMI percentile (p = 0.000), HOMA index (p = 0.002), systolic blood pressure (p = 0.02), leptin (p = 0.001), omentin-1 (p = 0.001), adiponectin (p = 0.001) levels were higher, vaspin level was lower (p = 0.008) in the (O/O) group compared to the controls. There was a positive correlation between HDL and vaspin, and a negative correlation between HDL and omentin-1 in the O/O group. Also it was observed that as the degree of hepatosteotosis increased, leptin (p = 0.004), omentin-1 (p = 0.001) levels were increased. There was no significant change in vaspin level (p = 0.128). The high levels of omentin-1, leptin and adiponectin have an association with the development of hepatosteatosis in O/O children.

• Korean Journal of Agricultural and Forest Meteorology
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• v.20 no.1
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• pp.117-126
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• 2018

The purpose of this study is to analyze the spatial distribution characteristics and spatial changes of Automatic Weather Stations (AWS) in mountainous areas with altitude more than 200 meters in South Korea. In order to analyze the spatial distribution patterns, spatial analysis was performed on 203 Automatic Mountain Meteorology Observation Station (AMOS) points from 2012 to 2016 by Euclidean distance analysis, nearest neighbor index analysis, and Kernel density analysis methods. As a result, change of the average distance between 2012 and 2016 decreased up to 16.4km. The nearest neighbor index was 0.666632 to 0.811237, and the result of Z-score test was -4.372239 to -5.145115(P<0.01). The spatial distributions of AMOSs through Kernel density analysis were analyzed to cover 129,719ha/a station in 2012 and 50,914ha/a station in 2016. The result of a comparison between 2012 and 2016 on the spatial distribution has decreased about 169,399ha per a station for the past 5 years. Therefore it needs to be considered the mountainous regions with low density when selecting the site of AMOS.

• Journal of Life Science
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• v.20 no.12
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• pp.1844-1850
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• 2010

Body fat reducing and physical-activity enhancing effects, along with artherosclerosis improving effects, of conjugated linoleic acid (CLA) were elucidated on obese male middle school students with more than 30% body fat. Twenty-four volunteers were randomly divided into control (placebo, n=12) and CLA treatment (n=12) groups. Subjects were daily fed 6 g CLA (6 capsules, twice a day) or a placebo for 12 weeks. At the end of the experiment, body composition, blood lipid composition and exercise capacities of subjects were measured. CLA significantly reduced body fat content and body mass index (BMI) along with body weight, while the placebo did not have any such effects. Similarly, CLA significantly reduced low-density lipoprotein (LDL)-cholesterol, total cholesterol, and triglyceride, but elevated high-density lipoprotein (HDL)-cholesterol content in blood. Meanwhile, in terms of exercise capacity, there were significant enhancements of trunk flexion, closed-eyes foot balance, standing long jump, shuttle run, and sit-up activities in the CLA treatment group. These results indicate that CLA consumption reduced body fats, improved atherosclerosis factors in blood and improved physical activity of young male obese middle school students, and suggest that CLA could be a useful material for the heath care of obese young men.

• Asian Journal of Turfgrass Science
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• v.25 no.1
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• pp.94-99
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• 2011

This study was performed to investigate the effect of foliar feeding as the fertilization on creeping benrgrass green. Research results have showed that the visual quality of bentgrass as well as shoot density and chlorophyll index dramatically improved after foliar feeding. Shoot density of bent grass in foliar based fertilization was 2.8 ea/$cm^2$ higher than that of the liquid based fertilization during the experiment period, moreover that the foliar feeding is more effective to alleviate shoot density during the rainy season in summer. Results showed that foliar feeding was key role to achieve the stable visual quality, chlorophyll index and maintained Normalized Difference Vegetation Index (NDVI) throughout the year in addition to get fast recovery after aeration and dry spot. These were consistent with the previous research of foliar feeding which directly provided nutrient to the turfgrass leaf thus increased turfgrass growth within a short time. It is projected to be a especially adequate management program during the hot summer season in which the nutrition feeding is low. However, root growth was no significant difference between foliar based fertilization and liquid based fertilization. Golf Course managers also should consider about the number of frequent fertilizing. Lastly, it was no big change in chemical property by soil foliar based fertilization which is meaning of preventing the soil salinization, meanwhile, it is prone to reach the nutrient deficiency. It hopes to be settled as the general fertilization in golf course of Korea, since there are many advantages of foliar based fertilization program. It is suggested to study more practical process of foliar feeding through the further research.

• Korean Journal of Environmental Biology
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• v.36 no.4
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• pp.626-637
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• 2018

In this study, a series of survey were conducted to identify the distribution patterns of macrobenthos at the Bongam sand tidal flat in Masan Bay. We collected macrobenthos at 9 sampling sites twice in June and September of every year from 2012 to 2017 using a box core sampler (collecting area, $0.025m^2$). There was a total of 50 species with a community density of $6,388ind.m^{-2}$ and a biomass of $313.9g\;wet\;m^{-2}$ during the study period. Polychaetes had the highest number of species and density among the macrofauna, but the mollusks had the largest biomass. The number of species ranged from 10 to 25 during study period but increased to over 20 species in 2014. The density which ranged from $1,508ind.m^{-2}$ to $12,008ind.m^{-2}$ rapidly increased in 2015. The dominant species were all polychaetes such as Heteromastus filiformis, Prionospio japonicus, Hediste diadroma, and Neanthes succinea. The mean diversity index ranged from 1.2 to 1.9, richness index from 1.2 to 2.4, and evenness index from 0.5 to 0.9. From the cluster analysis results, there was a spatial difference in the similarity of faunal composition of macrobenthos and this pattern was maintained throughout the study period, that is, the temporal similarities were higher than the spatial similarities. There was a change in community composition from June 2014 to June 2015 in most of the sampling sites. During this time, the dominant species also changed from H. filiformis and N. succinea to H. filiformis and H. diadroma. The density of opportunistic species such as Capitella capitata and Polydora ligni decreased compared to the early 2000s while the population of H. diadroma increased from 2015. There was little ecological information on H. diadroma such as when and where this species occurred.