• Journal of the Korean Wood Science and Technology
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• v.12 no.4
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• pp.3-10
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• 1984

In hot pressed wood of Pseudotsuga menziesii compressed to 0 - 50 percent at temperature 60 - $180^{\circ}C$, relative humidity conditions affecting dynamic Young's modulus of elasticity and internal friction were investigated. The results obtained are summarized as follows: Moisture absorption of the hot pressed wood decreased with increasing press temperature, but there was no effect on the amount of compression. Thickness swelling dereased with increasing press temperature, and increased with increasing amount of compression. In general, dynamic Young's modulus of elasticity showed a straight line with increasing specific gravity of specimens. Dynamic Young's modulus of elasticity decreased with increasing moisture content, but internal friction increased with increasing amount of moisture content. Dynamic Young's modulus of R specimens pressed in the radial direction showed hight values than T specimens pressed in the tangential direction.

• Proceedings of the KIEE Conference
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• 1987.07a
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• pp.416-419
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• 1987

The miniaturization of Bird's Beak generated at the field oxidation has been studied by adding polysilicon layer between the silicon nitride and pad oxide stack, which is the basic structure of Conventional LOCOS. The size and shape of Bird's Beak were intensively observed by SEM, and also the electrical characteristics of Bird's Beak-reduced LOCOS structure were compared with those of Conventional LOCOS. The length of Bird's Beak was reached up to $0.20-0.28{\mu}m$, while about to $0.50-0.53{\mu}m$ in conventional LOCOS, resulting in 60% reduction.

• Journal of the Korean Solar Energy Society
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• v.32 no.2
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• pp.95-104
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• 2012

This study purposed to predict wind energy for small size wind power generators at 50m above the ground in each area using mean wind speed data for 10 minutes collected from 2001 to 2011 by meteorological data in large cities having over 60% of 15 story (50m) or higher apartments including Seoul, Daejeon, Gwangju and Daegu representing the inland region, and Busan, Incheon and Ulsan representing the coastal region. In the results of analysis, we confirmed close agree ment between observatory weather data and probability density distribution obtained using Weibull's parameters, and this suggests that Weibull's parameter is applicable to the estimation of wind energy. Hourly output energy using the mean wind speed for 10 minutes and output energy obtained from Weibull's parameter showed an error less than 5%, and thus it was found that wind energy can be evaluated using Weibull's modulus.

• Journal of Environmental Health Sciences
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• v.36 no.3
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• pp.215-221
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• 2010

The purpose of this study was to investigate the relevance of gender, age, and BMI (Body Mass Index) to changes in the urinary creatinine concentration in Korean adults. We recruited and surveyed 2,156 persons $\geq$20 years of age from 98 districts across the country, and collected urine samples for analyzing the creatinine concentration. Participants were 41.6% men and 58.4% women. In terms of age, the percentage of the population in their 20's and $\geq$60 years of age was relatively similar, with 13.6% and 17.8%, respectively, while the percentages in their 30's, 40's and 50's were also relatively similar, with 22.0%, 24.0%, and 22.6%, respectively. The proportion of participants in their 20's and 30's who were underweight (according to the BMI) was 25% and 19.2%, respectively, but only 6.2~6.4% of those $\geq$40 years of age were underweight. This showed that the underweight proportion in elder generations was less than that in younger generations. Meanwhile, the proportion who were overweight was 13.7%, 18.8%, 28.6%, 27.9%, 32.0% when the participants were in their 20's, 30's, 40's, 50's and $\geq$60 years of age, respectively (p<0.000). This showed that the overweight proportion increased along with increasing age. The overall urinary creatinine concentration was 10 mg/dl (arithmetic mean: AM), and 92.2 mg/dl (geometric mean: GM). The urinary creatinine concentration in men (132.6 mg/dl, AM) was significantly higher than that in women (93.3 mg/dl, AM (p<0.000)). Showing a similar trend in men and women, urinary creatinine concentrations were highest when the participants were in their 20's (135.6 mg/dl, AM), and tended to decrease with increasing age. Urinary creatinine concentrations in overweight and obese subjects (AM of 117.9 mg/dl and 118.0 mg/dl, respectively) were significantly higher than in other groups, and this trend was similar in men and women. In conclusion, we found that urinary concentrations were significantly affected by gender, age, and BMI, and that care should therefore be exercised when correcting urinary metabolites according to the urinary creatinine concentration.

• Elastomers and Composites
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• v.34 no.5
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• pp.414-422
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• 1999

SBR, polyurethane and epoxy latex were separately blended with ethylene-vinyl acetate(EVA) emulsion In $0{\sim}50%$. EVA emulsion was not reacted with latexes in liquid phase and mixtures had good stroage stability. The viscosity of cement mixtures was elevated to 20,000cps in $0.5{\sim}2.0$ hours by mixing. The mixtures mixed with pigment represented high viscosity and showed higher viscosity as time goes by. Mixtures had higher hardness with mixing SBR than mixing epoxy or urethane. The hardness was suddenly increased over cement content 30%. showed pencil hardness $H{\sim}2H$ in $50{\sim}60%$. The increase of hardness in high solids was depended upon not only the condensation of latexs but also the coagulation and adhesion of cement particle.

• Journal of the Korean Ceramic Society
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• v.50 no.6
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• pp.485-488
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• 2013

A SiC-$CeO_2$ composite membrane was successfully fabricated using an ally-hydridopolycarbosilane (AHPCS) binder and treated by dip-coating at 60 times with a $CeO_2$ sol solution. The dip-coated SiC membrane was calcined at 773 K and then sintered at 1173 K under an air atmosphere. The coated membrane was characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM) and a BET surface analysis. The difference in permeation performance between $H_2$ and CO gases was measured by varying the temperature. The permeation flux of $H_2$ on the SiC membrane with layered $CeO_2$ was obtained as $8.45{\times}10^{-6}\;mol/m^2sPa$ at room temperature. The CO permeation flux was $2.64{\times}10^{-6}\;mol/m^2sPa$ at room temperature. The reaction enthalpy (${\Delta}H^{\circ}$) for the hydrogen permeation process was calculated as -7.82 J/mol by Arrhenius plots.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2008.04a
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• pp.117-119
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• 2008

This study was investigated for the dyeing properties of silk fabrics with Annatto Extract. The dye stuff was extracted by distilled water at 60$^{\circ}C$, 10minutes, 100:1 of bath ratio. The highest K/S value was showed at 25% dye concentration, 60minutes of dyed time at 50$^{\circ}C$ in the temperature. The post mordant conditions were better than that of pre mordant, especially post-Fe mordant showed highest K/S value. The laundering fastness was relatively good by Cu-mordant. Drying cleaning fastness appeared 4-5 grades.

• Food Science and Preservation
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• v.13 no.5
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• pp.603-610
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• 2006

Korean traditional soy paste (Doenjang) was fermented using Meju prepared by the culture of wild microorganisms in steamed soy beans. During the fermentation, changes in the physicochemical and several functional properties were monitored. Total acidity and amino acidity increased from 0.09 to 0.96, and 2.24% to 3.28% respectively, Amylase and protease activities increased and showed the maximal level after 60 days of fermentation, which were 4.03 and 7.29 units/ml, respectively. However, both enzyme activities decreased after then. The inhibitory activities against tyrosinase and angiotensin converting enzyme increased and reached 20.57 and 38.18% respectively. Antimutagenic activities against N-methyl-N'-nitro-N-nitiosoguanidine and 4-nitro-O-phenylenediamine (NPD) increased for 90 days and roached 70.21 and 60.01% in S. enterica serovar Typhimurium TA100, respectively. Against NPD and 4-nitroquinoline-1-oxide, the antimutagenic activities also increased and reached 50.91 and 46.35% in the strain TA98, respectively.

• Journal of Practical Agriculture & Fisheries Research
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• v.16 no.1
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• pp.123-133
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• 2014

We assessed the physical habitats of Microphysogobio longidorsalis in the Han river basin. Field monitoring was conducted for ecological and habitat conditions for 11 sites from October 2008 to November 2011. Twenty species (50.0%) including M. longidorsalis and Zacco koreanus were found endemic out of the 40 species in 10 families sampled during this study period. The most frequently found species was Z. platypus (26.2%) followed by Z. koreanus (17.7%), Coreoleuciscus splendidus (14.0%) and M. longidorsalis (13.4%). For M. longidorsalis, total fist length showing the highest number of samples were 8~10 cm (50.9%). the favored habitat conditions were estimated to be 0.4~0.5 m (56.1%) for water depth, 0.2~0.9 m/s (90.4%) for flow velocity, sand (0.1~1.0 mm)~cobbles (100.0~300.0 mm)(94.5%) for substrate size and run (60.2%) for habitat type, respectively.

• Journal of agriculture & life science
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• v.50 no.5
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• pp.217-224
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• 2016

In this study, performance of a developed automatic punching machine considering the planting density of soybeans was evaluated in the case of the operation speed of 0.18-0.28 m/s. The performance demonstrated a rate of 320-500 ㎡/h, 260-400 ㎡/h, and 210-330 ㎡/h for the 0.20 m, 0.25 m, and 0.30 m soybean planting density, respectively. One hundred percent punching capacity was confirmed in 30 mm distance between the ground and the blade. Additionally, in the 50 mm distance condition, the performance of round, square, and hexagonal blades were observed in the range of 16.7-25.2%, 33.0-42.3%, and 54.5-100.0%, respectively. Above all, the hexagonal blade with a 60° edge angle had the most superior cutting quality demonstrating a smooth and soft cutting plane of the plastic.