• Journal of Ocean Engineering and Technology
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• v.23 no.1
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• pp.43-47
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• 2009

This paper compares theoretical wave profile and particle kinematics with experimental results generated by a 2 D wave tank. Particle velocity fields of compound waves were acquired using a PIV technique. Synchronization was applied to acquire images of the wave fields, and the time gap between these images was controlled by the user. This technique was applied to investigate the wave breaking mechanism, and the wave profile and velocity distribution in a wave breaking field was obtained.

• Applied Chemistry for Engineering
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• v.18 no.5
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• pp.438-443
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• 2007

Titanium oxide films were deposited by the HCP (hollow cathode plasma) reactor at room temperature. With results of simulation about HCP reactor, the temperature profile is uniform on substrate regardless of the heat generation at cathode. The velocity profile on the surface of substrate is more uniform with increasing the gap between cathode and substrate, and surface roughness was decreased with increasing the gap between cathode and substrate. We could confirm that the composition of oxide increased with RF-power, and the ratio of O to Ti in the films was about 2 : 1 at RF-power of 240 watt and distance between cathode and substrate of 3 cm.

• Journal of the Korean Ceramic Society
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• v.32 no.9
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• pp.1009-1018
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• 1995

(Ti.Si)C composite powders were synthesized by SHS method using microwave energy. Compositional and structural characterization of the powder were carried out by using scanning electron microscopy and X-ray diffraction. The average particle size of the synthesized (Ti.Si)C composite powders was smaller than that of the starting materials. From the results of the temperature profile, combustion temperature and velocity were decreased with increasing Si molar ratio. With increasing C molar ratio combustion temperature and velocity did not change. (Ti.Si)C composite was sintered at 185$0^{\circ}C$ for 60 min by using hot-pressing with 30 MPa. The best properties were obtained from the sintered specimen whose composition was 1 : 1 : 1.9 molar ratio of Ti : Si : C. The sintering density, flexural strength and vickers hardness of the sintered body were 4.71 g/㎤, 423 MPa and 21 GPa, respectively.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.1
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• pp.9-13
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• 2008

This study was performed to investigate the quality characteristics of yanggaeng prepared with different ratios of Astragalus membranaceus powder : 2%, 4%, and 6%. Proximate composition, Hunter's color values, texture profile analysis, and sensory qualities were examined. The lightness of the yanggaeng decreased with increasing Astragalus membranaceus powder content. For the texture profile analysis, hardness increased with increasing Astragalus membranaceus powder content. In terms of sensory qualities, the 2% Astragalus membranaceus powder sample did not influence any of the sensory attributes of the yanggaeng.

• Journal of Ecology and Environment
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• v.41 no.9
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• pp.271-280
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• 2017

Background: Soil microorganisms play key roles in nutrient cycling and are distributed throughout the soil profile. Currently, there is little information about the characteristics of the microbial communities along the soil depth because most studies focus on microorganisms inhabiting the soil surface. To better understand the functions and composition of microbial communities and the biogeochemical factors that shape them at different soil depths, we analyzed microbial activities and bacterial and fungal community composition in soils up to a 120 cm depth at a fallow field located in central Korea. To examine the vertical difference of microbial activities and community composition, ${\beta}$-1,4-glucosidase, cellobiohydrolase, ${\beta}$-1,4-xylosidase, ${\beta}$-1,4-N-acetylglucosaminidase, and acid phosphatase activities were analyzed and barcoded pyrosequencing of 16S rRNA genes (bacteria) and internal transcribed spacer region (fungi) was conducted. Results: The activity of all the soil enzymes analyzed, along with soil C concentration, declined with soil depth. For example, acid phosphatase activity was $125.9({\pm}5.7({\pm}1SE))$, $30.9({\pm}0.9)$, $15.7({\pm}0.6)$, $6.7({\pm}0.9)$, and $3.3({\pm}0.3)nmol\;g^{-1}\;h^{-1}$ at 0-15, 15-30, 30-60, 60-90, and 90-120 cm soil depths, respectively. Among the bacterial groups, the abundance of Proteobacteria (38.5, 23.2, 23.3, 26.1, and 17.5% at 0-15, 15-30, 30-60, 60-90, and 90-120 cm soil depths, respectively) and Firmicutes (12.8, 11.3, 8.6, 4.3, and 0.4% at 0-15, 15-30, 30-60, 60-90, and 90-120 cm soil depths, respectively) decreased with soil depth. On the other hand, the abundance of Ascomycota (51.2, 48.6, 65.7, 46.1, and 45.7% at 15, 30, 60, 90, and 120 cm depths, respectively), a dominant fungal group at this site, showed no clear trend along the soil profile. Conclusions: Our results show that soil C availability can determine soil enzyme activity at different soil depths and that bacterial communities have a clear trend along the soil depth at this study site. These metagenomics studies, along with other studies on microbial functions, are expected to enhance our understanding on the complexity of soil microbial communities and their relationship with biogeochemical factors.

• The Korean Journal of Food And Nutrition
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• v.29 no.5
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• pp.785-794
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• 2016

This research was conducted to evaluate quality changes in traditional Doenjang and manufactured Doenjang during a storage period of 8 weeks. Low-salt Doenjang and commercial Doenjang were purchased from different manufacturers and proximate analysis as well as changes in isoflavone, polyphenol, flavonoid contents of the samples were investigated using a mass spectrophotometer. The salinity of traditional Doenjang, low salt Doenjang, and commercial Doenjang were $13.2{\pm}1.15$, $7.17{\pm}2.74$, $10.67{\pm}0.35%$, respectively and the salt concentrations of the soybean pastes did not change during storage. After 8 weeks at $35^{\circ}C$, chromatic values of all the paste samples decreased somewhat, with traditional Doenjang exhibiting fewer changes as compared to manufactured Doenjang. Amino acid nitrogen, acidity, microbial population all tended to increase with time, although some samples showed fluctuations during the test period. Moreover, the total isoflavone contents of traditional Doenjang increased with storage time while that of manufactured Doenjang tended to decrease. The isoflavone aglycone was shown to be the highest in traditional Doenjang, while isoflavone glycoside was abundant in manufactured Doenjang. Total flavonoid contents showed similar trends regardless of samples; initial contents of total flavonoid was 0.6 mg/g which increased to more than twice to 1.4 mg/g at the end of storage period. Composition profile of Doenjang extracts was analyzed using UPLC-Q-ToF.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.5
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• pp.391-398
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• 2013

Soil organic carbon (SOC) has the potential to promote the soil quality for sustainability and mitigation of global warming. There is little information on organic carbon composition despite of having resistance of carbon degradation in soil. In this study, to understand the effect of volcanic ash on organic carbon composition and quantity in soil, we investigated characteristics of volcanic soil and compared organic carbon composition of soil and humic extract by using $^{13}C$-CPMAS-NMR spectra under soil profiles of Namweon series in Jeju. SOC contents of inner soil profiles were 134.8, 101.3, and 27.4 g C $kg^{-1}$ at the layer of depth 10-20, 70-80 and 90-100 cm, respectively. These layers were significantly different to soil pH, oxalate Al contents, and soil moisture contents. Alkyl C/O-alkyl C ratio in soil was higher than that of humic extracts, which was decreased below soil depth. Aromaticity of soil and humic extract was ranged from 29-38 and 24-32%, which was highest at the humic extract of 70-80 cm in soil depth. These results indicate that the changes of SOC in volcanic ash soil resulted from alteration of organic composition by pyrolysis and stability of organic carbon by allophane in volcanic ash soil.

• Journal of the Korean Society of School Health
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• v.19 no.1
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• pp.67-78
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• 2006

Purporse : The purpose of this study was to examine the relationship between a health promoting lifestyle and body composition in university students. The study subjects were 194 university students who attended K-university located in Chungnam. Methods : The data was collected between March 2 and May 31, 2004. The instrument used for this study was the modified Health Promoting Lifestyle Profile(HPLP) developed by Walker, Sechrist, & Pender(1987). The body composition was measured by In Body 3.0, a Bioelectrical Impedance Analyzer. The data was analyzed using the SPSS/WIN 10.0 program by t-test, ANOVA and pearson correlation coefficients. Results : The results of this study are as follows: 1) The scores of the Health Promoting Lifestyle(HPL) ranged from 79 to 170, with a mean score of 110(±15.8). The mean scores of sub-categorical HPL were self-actualization 31.8(±4.9), health responsibility 17.0(±4.0), exercise 8.3(±3.2), nutrition 15.4(±3.7), interpersonal relationships 20.3(±3.5) and stress management 17.2(±3.4). 2) The HPL according to the subjects' general characteristics had significant correlation to exercise amount(F=8.09, p＜.01), drinking amount(F=6.56, p＜.01), perceived health status(F=19.2, p＜.01) and perceived health knowledge (F=15.9, p＜.01). 3) The total HPL did not significantly correlate with any categories in body composition. The exercise area of sub-categorical HPL had significant positive correlation to height (r=.199, p＜.01), weight(r=.181, p＜.05) and soft lean mass(r=.257, p＜.01), and negative correlation to percent body fat(r=-.255, p＜.01) in body composition. Conclusion : The results suggest that the exercise area of sub-categorical HPL was an important variable for an exercise program's development such as nursing intervention for the health promotion of university students.

• Journal of Mechanical Science and Technology
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• v.14 no.3
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• pp.298-305
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• 2000

The functionally graded material (FGM) is the new concept for a heat resisting material. FGM consists of ceramics on one side and metal on the other. A composition and microstructure of an intermediate layer change continuously from ceramics to metal at the micron level. This study is carried out to analyze the thermal shock characteristics of functionally graded PSZ/ metal composites. Heat-resistant property was evaluated by gas burner heating test using $C_2H_2/O_2$ combustion flame. The ceramic surface was heated with burner flame and the bottom surface cooled with water flow. Also, the composition profile and the thickness of the graded layer were varied to study the thermo mechanical response. Furthermore, this study carried out the thermal stress analysis to investigate the thermal characteristics by the finite element method. Acoustic emission (AE) monitoring was performed to detect the microfracture process in a thermal shock test.

• Natural Product Sciences
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• v.11 no.4
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• pp.225-228
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• 2005

four varieties of ground nut (Arechis hypogea) were collected from different areas of Pakistan (Tillagang, Gujar khan, Hanoi and Pipplan) from Punjab province. The oils were extracted for the evaluation of lipid. Physico-chemical values of oils were determined like refractive index, peroxide value, unsaponifiable matter, acid value, iodine value, free fatty acid and ester value. The lipid profile as indicated by GLC showed that Palmitic acid ranged from 8.2-8.8%, proportions of oleic acid and linoleic acid varied from 57.8-59.87% and 22.5-24.1% respectively. Gujar khan variety of peanut has higher % age of oil (56.79). The higher yield of oil in this variety is not at the cost of any nutritional quality of peanut oil.