• Journal of Korean Ophthalmic Optics Society
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• v.10 no.4
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• pp.267-272
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• 2005

We deposited thin films of organic light-emitting-material $Alq_3$(alumina quinoline) on silicon and slide-glass substrates using thermal evaporation method, and measured spectra of ellipsometry angles ${\Delta}$ and ${\Psi}$ in the photon-energy range of 1.5~5.0 eV using a variable angle spectroscopic ellipsometer. The optical constants, refractive index and extinction coefficient, of $Alq_3$ were determined via the dispersion parameters extracted from the curve-fitting process based on Jellison-Modine dispersion function. The reliability of determined optical constants were verified through the comparison of measured and simulated transmittance curves and the good agreement between simulated absorption-coefficient curves and absorbance spectra measured using a spectrophotometer.

• Journal of the Korean Dietetic Association
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• v.21 no.3
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• pp.181-193
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• 2015

This study investigated anthropometric and biochemical characteristics, nutrient intakes, and bone density of Korean elderly men (over 65 yrs). Data on bone density and anthropometric (height, weight, waist circumference, body mass index and blood pressure) and biochemical (total cholesterol, high-density lipoprotein (HDL)-cholesterol, low-density lipoprotein (LDL)-cholesterol, triglyceride and hemoglobin) characteristics, nutrient intakes, and nutrient density were obtained from the Fifth Korea National Health and Nutrition Examination Survey (KNHANES, 2008~2011). Subjects were categorized into smoking and non-smoking groups, and smoking groups were divided into three groups by smoking period (under 20 yrs, 21~40 yrs and over 41 yrs). Serum triglyceride concentrations of the smoking group aged 21~40 yrs were higher than those of other groups (P<0.01), whereas other biochemical factors were not different. Intake ratios of energy, protein, phosphorus and sodium in subjects were over 100% of Dietary Reference Intake for Koreans (KDRI). Nutrient densities according to intakes of thiamin, riboflavin, and niacin per 1,000 kcal were significantly different among the groups (P<0.05). Bone density of subjects decreased according to smoking period (T-score of total femur in non-smoking group -0.3108, and -0.2918, -0.4941, -0.6847 in smoking group, respectively). Ratio of osteoporosis was 38.1% in the non-smoking group and 44.4%, 51.1%, and 64.0% in the smoking group, respectively. The findings of the present study show that smoking may be associated with bone health, higher ratio of osteoporosis, and low nutrient density in elderly men. Therefore, practical and systematic non-smoking programs are required to improve the bone density of elderly men as well as maintain healthy bone levels and desirable lifestyle.

• Nutrition Research and Practice
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• v.5 no.4
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• pp.329-336
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• 2011

Obesity contributes to an increased risk for chronic diseases, including diabetes, cardiovascular diseases, and certain types of cancer. The prevalence of obesity has increased in Korea. We compared the clinical and dietary characteristics of obese adults (n = 30, 17 men and 13 women, mean age 29.9) to those with a normal weight (n = 15, 8 men and 7 women, mean age 26.5). We determined lipid profiles, fasting blood sugar (FBS), blood pressure, and serum free fatty acid (FFA). Dietary intake was estimated using a food frequency questionnaire (FFQ) and a 3-day dietary record. Exercise patterns and average alcohol intake were determined. The average body mass index was 28.3 kg/$m^2$ in the obese and 21.2 kg/$m^2$ in the normal weight groups. The obese group had significantly higher levels of total cholesterol, LDL cholesterol, and triglycerides, lower levels of HDL cholesterol, and higher blood pressures compared to the normal weight group. FBS was not significantly different between the two groups. The obese group had significantly more subjects with metabolic syndrome (26.7%) compared to the normal weight group (0%). Serum FFA levels tended to be higher in the obese (P = 0.087). No significant difference in caloric intake was observed between the two groups. No differences in carbohydrate, protein, or fat intake between two groups were observed from the FFQ. However, results from the 3-day dietary record showed that the percentage of energy from fat was significantly higher in the obese group. The frequency and amount of exercise did not differ between the two groups. Alcohol consumed per drinking episode was significantly higher in the obese group. These results confirm that excessive weight is associated with disturbances in lipid metabolism in these fairly young and otherwise healthy adults. Dietary factors, including higher fat intake and alcohol consumption, seem to be contributing to the obesity of these subjects.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.141-141
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• 2012

The electronic and optical properties of Indium Zinc Tin Oxide (IZTO) thin films using gas environment were investigated by X-ray photoelectron spectroscopy (XPS) and reflection electron energy loss spectroscopy (REELS). REELS spectra revealed that the band gaps of IZTO thin films are 3.26, 3.07, and 3.46 eV for water mixed with oxygen, argon mixed with oxygen, and air environments, respectively. The measured band gaps by REELS are consistent with the optical band gaps obtained by UV-Spectrometer. The optical properties represented by the dielectric function $\mathfrak{m}$, the refractive index n, the extinction coefficient k, and the transmission coefficient T of the IZTO thin films with different gas environments were determined from a quantitative analysis of REELS spectra. The calculated transmission from quantitative analysis of REELS spectra shows good agreement with transmission measured by UV-spectrometer. The transmission values of 89% and low electrical resistivity of $3.55{\times}10^{-3}{\Omega}{\cdot}cm$ have been achieved for argon mixed with oxygen which indicates that the gas enviroment plays an important role in improving the electronic and optical properties of films.

• Korean Journal of Environment and Ecology
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• v.26 no.5
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• pp.719-729
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• 2012

Baekdudan has 670km long within South Korea, so the study for detail vegetation characteristics is needed. In this study, we surveyed the plant community structure from Daetjae to Baekbongryung for the next restoration and management plan. We designated 40 quadrats ($10m{\times}10m(100m^2)$ for this study. As a result of TWINSPAN, plant community separated 8 different communities such as Abies koreana comm., Pinus densiflora comm., Quercus mongolica comm. and Larix kaempferi comm. etc. Abies koreana comm. and Pinus densiflora comm. which is mainly located in the mountain ridge and near rocks are needed avoidance from the competition with Quercus mongolica comm. The possibility of atrophy of these communities is to be high, the protection is needed. Species diversity index was between 0.8046~1.1283. Most communities have multi-layer structure and have the ecological value of protection.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.360-360
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• 2012

Zn-Sn-O (Zinc-Tin-Oxide; ZTO) thin films have been gaining extensive academic and industrial attentions owing to a semiconducting channel materials applicable to large-sized flat-panel displays. Due to the constituent oxides i.e., ZnO and SnO2, the resultant Zn-Sn-O thin films possess artificially controllable bandgaps and transmittances especially effective in the visible regime. The current approach employed RF sputtering in depositing the Zn-Sn-O thin films onto glass substrates at ambient conditions. This work places its main emphases on the electrical/optical features which are closely related to the combinations of processing variables. The electrical characterizations are performed using dc-based current-voltage characteristics and ac-based impedance spectroscopy. The optical constants, i.e., refractive index and extinction coefficient, are calculated through spectroscopic ellipsometry along with the estimation of bandgaps. The charge transport of the deposited ZTO thin films is based on electrons characteristic of n-type conduction. In addition to the basic electrical/optical information, the delicate manipulation of n-type conduction is indispensible in diversifying the industrial applications of the ZTO thin films as active devices in information and energy products. Ultimately, the electrical properties are correlated to the processing variables along with the underlying mechanism which largely determines the electrical and optical properties.

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.5
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• pp.538-544
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• 1998

One hundred and twenty-eight finishing pigs (51.3 kg average initial body weight) were used to determine the effects of adding cellulase enzymes and lactobacillus acidophilus to sorghum-based diets on growth performance, carcass merit, and nutrient digestibility in finishing pigs. Treatments were: 1) corn-soybean meal-based positive control; 2) sorghum-soybean meal-based negative control; 3) Diet 2 with celluloytic enzymes; and 4) Diet 2 with a bacterial feed additive (lactobacillus acidophilus). There was a trend for greater average daily gain (ADG) in pigs fed com versus the sorghum treatments for day 0 to 28 (p < .09), but there was no effect of treatment (p > .15) on overall ADG (i.e., day 0 to 63). Feed consumption was not affected by treatment during the experiment (p > .19). Pigs fed the corn-soybean meal-based diet had 3.5% greater overall gain/feed than pigs fed the other diets (p < .009). Dressing percentage was not affected by treatment (p > .22), but there was a trend for backfat thickness at the last rib to be greater for pigs fed com versus the sorghum treatments (p < .09). Pigs fed the sorghum treatments had 1 % greater fat free lean index (p < .10) compared to pigs fed the corn-soybean meal-based positive control. Pigs fed com had greater apparent digestibilities of DM, N, and GE than pigs fed the sorghum treatments (p < .03), and greater DE intake (p < .07) suggesting that the increased carcass fatness for pigs fed the corn-based control diet resulted from greater energy status of those pigs. In conclusion, pigs fed the corn-soybean meal-based control diet had no improved growth performance but tended to be fatter than pigs fed sorghum. Adding cellulolytic enzymes or a bacterial feed additive to diets for finishing pigs did not affect growth performance, carcass merit, or nutrient utilization.

• Journal of the Korea Institute of Building Construction
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• v.20 no.3
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• pp.245-252
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• 2020

Synthetic resin formwork is made of lightweight high-density polyethylene(HDPE). This study used a process flow chart that satisfies the system boundary (such as Cradle-to- Product shipmen ) required by ISO FDIS 13352 to evaluate the entire process of synthetic resin foam using. The entire life cycle inventory (LCI) database calculated from input energy sources, materials used, transportation methods, and manufacturing processes at the system boundary was analyzed. Based on the environmental impact assessment index methodology of the Ministry of Environment from the LCI data analysis of synthetic resin formwork, the environmental impact assessment was carried out through classification, normalization, characterization, and weighting process. The experimental results are as follows the amount of CO₂ (carbon) emission considering the number of conversions was about 32% lower than that of the Euroform. This shows that the use of synthetic resin formwork reduces material production by half compared to Euroform and reduces CO₂ (carbon) emissions.

• Journal of the Korean Chemical Society
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• v.55 no.5
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• pp.733-740
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• 2011

Multiple regression analysis was used for the calculation of pKa values of 15 substituted benzaldoximes by using various types of descriptors as parameters. These descriptors are based on quantum mechanical treatments. They were derived by employing semi-empirical calculation represented by the PM3 model and an Abinitio method expressed by Hartree-Fock(HF) model performed at the 6-311 G(d, p) level of theory. The parameters tested for their ability to represent the variations observed in the experimental pKa(s) are atomic and structural properties including Muliken charges on the atoms of hydroxyl group and C=N bond, the angle $C_6-C_1-C_7$, and length of O-H bond. Molecular properties are also used like energies of HOMO and LUMO, hardness(${\eta}$), chemical potential(${\mu}$), total energy(TE), dipole of molecule(DM), and electrophilicity index(W). The relation between pKa values and each of these parameters of the studied compounds is investigated. Depending on these relations, two sets of parameters were constructed for comparison between the PM3 and HF methods. The results obtained favor the Abinitio method for such applications although both models proved to have high predictive power and have sufficient reliability to describe the effect of substituents on pKa values of benzaldoxime compounds under consideration which is clear from the values of correlation coefficient $R^2$ obtained and the consistency between the experimental and the calculated values.

• Journal of the Korea Organic Resources Recycling Association
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• v.13 no.1
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• pp.115-123
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• 2005

In this study, life cycle assessment(LCA) technique was employed to evaluate the environmental impact of material recycling of polyethylene terephthalate(PET) bottle. Life cycle inventory was established based on the data collected from recycling companies in Korea. Simapro 5.0 LCA software and Eco-indicator 95 index were used for the analysis. The biggest impact by the material recycling of PET bottle on the environmental category was the global warming. It is because melting and production of the recycled PET product consume a significant amount of electricity and energy. In the environmental pollution discharge, $CO_2$ emission was the highest, followed by NOx. This is probably due to the use of diesel and gasoline in the consumption of electricity and transportation. All the environmental impact showed (-) value except the ozone layer depletion, which means that the material recycling of PET bottle is environmentally fair. The use of recycled PET product greatly reduced the environmental impact.