• Proceedings of the KIEE Conference
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• 2003.10a
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• pp.316-318
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• 2003

본 연구에서는 전기적 특성, 기계적 특성, 내수성 및 내유성이 우수한 고분자 화합물로 산업용, 콘덴서절연재료용, 의료센서용 등 각종 절연재료 및 유전재료로 활용되어 지고 있는 변환기용 PET박막에 광자선을 10[Gy] 15[MeV], 30[Gy] 15[MeV], 50[Gy] 15[MeV]를 조사하여 물성분석 및 전기적 특성중 유전정접 특성에 관하여 검토하였다. 물성분석으로 X-선 회절(XRD) 분석 결과 조사량에 따라 피크의 크기가 커지므로 결정성이 더욱 좁아짐을 알수 있었으며 적외선 분광(FTIR) 측정결과로 파수 1752[$cm^{-1}$]에서는 C=O기의 신축운동 기여로 피크가 나타나며 파수 1266[$cm^{-1}$]에서 =C-O기의 신축운동기여와 그리고 1019[$cm^{-1}$]에서는 벤젠환의 진동기여로 흡수 피크가 나타남을 알 수 있었고, 전자현미경을 이용하여 800배로 확대한 시료의 파단면을 조사한 결과 결정질과 비정질 영역이 혼재하고 있는 것을 확인하였다. 유전정접 특성으로는 측정온도범위 상온에서 130[$^{\circ}C$]와 인가전압 범위 1[V]에서 20[V]를 변화시켜 각각의 조사량에 대한 PET 박막의 유전특성의 온도의존성 및 주파수 의존성에 대하여 실험한 결과 변환기 재료의 가능성을 조사하였다.

• Korean Journal of Community Nutrition
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• v.12 no.6
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• pp.714-723
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• 2007

Especially, the teenage period, an important lifetime to develop both physically and mentally, needs to be helpful to promote the growth of the body and to keep a well-balanced mind through a balanced and nourishing diet. It is well known that the western style fast food is the most liked meal by teenagers. Wrong recognition about fast food and its frequent intake by adolescents can lead to unbalanced diet and food behaviors which may also connect with a poor impact on their personalities as well as their physical health. In this study, therefore, relationships between fast food intake frequency and food behavior, sociability, and personality, such as anger expression, were surveyed from 1,295 adolescents (666 in Seoul, 316 in Changwon, and 313 in rural communities), and then analyzed using SPSS program. The results are shown as follows. The fast food preference score and the fast food intake frequency score showed no differences between male students (22.9/30, 14.4/30 respectively) and female students (23.0/30, 14.0/30 respectively). But, the fast food preference score correlated positively with the intake frequency score (r=0.304) significantly (p<0.001). The more frequently eating of fast food group showed significantly lower scores (r=-0.233, p<0.001) in food behaviors. The frequency of fast food intake had no relationships with sociability, but it had a significantly effect on anger expression (r=0.213, p<0.001) and control (r=-0.l47, p<0.001). From these results, we could see the necessity of various nutrition education programs to build proper eating-out habits and also more studies are needed to find the relationships between fast food intake and growth and personality.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.16 no.4
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• pp.316-329
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• 1983

The formation and structure of the shelf front in the eastern part of the Yellow Sea are studied on the basis of oceanographic data collected in August, 1982 and February, 1983. This paper also describes the distribution of planktonic organisms of the shelf front. In summer the shelf front is formed in the area ($126^{\circ}02^'E-126^{\circ}05^'E$) ca. 20 miles from the shore at the depths of 15-25 m. in winter, however, no distinct shelf front is formed. Based on the cluster analysis of surface phytoplankton the species composition shaws a discontinuous pattern in the vicinity of the shelf front in summer, 1982. A similar trend is observed in distribution of some copepod species in winter, l983.

• Environmental Engineering Research
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• v.20 no.4
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• pp.336-341
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• 2015

The industrial-scale biological treatment of Chinese nutgall processing wastewater was conducted with a $200m^3$ expanded granular sludge bed reactor and a $900m^3$ bio-contact oxidation reactor. The temperature of the two reactors was controlled under mesophilic conditions ($32-40^{\circ}C$), through changing the proportion of the dilution water, which was composed of steam condensation water and residual circulating water. The effluent COD, gallic acid, chroma, total nitrogen, total phosphorus levels and pH of both the expanded granular sludge bed and bio-contact oxidation reactors were monitored. In addition, the redox potential in the expanded granular sludge bed was recorded. The total COD removal efficiency was 87.257% when the influent COD concentration was $14\;251{\pm}3\;148mg/L$, and the ratio of wastewater: dilution water was 1:5. The removal efficiencies of gallic acid, chroma, total nitrogen, and total phosphorus were 72.221%, 43.940%, 64.151% and 39.316%, respectively. The effluent pH increased in either the expanded granular sludge bed reactor or the bio-contact oxidation reactor during the operation. The redox potential in the expanded granular sludge bed varied between -367 mV and -435 mV. The results indicate that the combined process was suitable for treating Chinese nutgall processing wastewater.

• Journal of Nutrition and Health
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• v.6 no.3
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• pp.17-20
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• 1973

Quantitative analysis was achieved by gas-liquid chromatographic method (GLC) with a single column system of OV-17 for 16 of free amino acids in Korean green tea and the contents of mineral in it was determined by atomic absorption flame emission. The results are summarized as follows: 1) Korean green tea contained Mn 1% or over out of the total ash content and $0.05{\sim}0.20%$ in the water extraction, as the major mineral. 2) Ba, Cr, Ni, Pb and V were analyzed also by small quantities relatively and Co, Tin and Ywere not detected in the water extraction. 3) GLC indicated the presence of 16 components in free ammo acids. 4) The quantities of free amino acids in Korean green tea were determined $2.96{\sim}6.61%$ Alanine, $1.01{\sim}l.89mg%$ Glycine, $2.07{\sim}7.81mg%$ Valine, $1.27{\sim}8.76mg%$ Leucine and Isoleucine, $94.31{\sim}316.27mg%$ Threonine, $9.10{\sim}39.91mg%$ Serine, $2.18{\sim}36.76mg%$ Hydroxyproline, $2.72{\sim}5.90mg%$ Proline, $39.64{\sim}70.02mg%$ Aspartic Acid, $25.93{\sim}101.28mg%$ Glutamic Acid and Lysine, $8.32{\sim}18.30mg%$ Phenylalanine and Tyrosine in trace amount. 5) The total free amino acid contents in Korean green tea ranged from 207.24mg% to 516.06mg% and Moo-Deoung tea contained outstandingly high, 516 mg% or over.

• Journal of Hydrogen and New Energy
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• v.23 no.6
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• pp.573-580
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• 2012

Corrosion resistance and basic physical properties of solid tantalum are not comparable to most of the structural metallic materials. The relative high cost and melting temperature of tantalum are obstacles to be widely applied to general engineering processes. Electrodeposition in molten salt enables compact and uniform tantalum coating. In this study, Ta was coated onto base metal (SUS316L) with different current densities (0.5, 5, $20mA/cm^2$) by using MSE (Molten Salt Electrodeposition). In this study, it showed that deposition efficiency and microstructure of Ta coating layer were strongly depended on current density. In the case of the current density of $5mA/cm^2$, densest microstructure was obtained. The current density above $5mA/cm^2$ caused non-uniform microstructure due to rapid deposition rate. Dense microstructure and intact coating layer contributed to significant corrosion resistance enhancement.

• The Korean Journal of Community Living Science
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• v.23 no.3
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• pp.307-316
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• 2012

To evaluate the effect of Ulmus davidiana powder on rice dasik, Ulmus davidiana dasik was made after supplementation with Ulmus davidiana powder(0, 3, 6, 9 and 12%(all w/w)). The proximate component of Ulmus davidiana powder was 7.49% moisture content, 2.33% crude protein, 0.84% crude fat, 14.09% crude fiber and 8.50% crude ash. The moisture content of samples were significantly(p<0.05) lower than that of dasiks with Ulmus davidiana powder. The pH values were significantly decreased with increased Ulmus davidiana powder(p<0.05). The lightness(L-value) was significantly decreased as Ulmus davidiana powder increased(p<0.05). Redness(a-value) of dasik with Ulmus davidiana powder was significantly higher than that of the control group. However redness was decreased with the amount of increased Ulmus davidiana powder. The yellowness(b-value) decreased significantly as Ulmus davidiana powder increased(p<0.05). In the mechanical evaluation, hardness in the groups with Ulmus davidiana powder increased significantly(p<0.05). Adhesiveness of the control group was lower than that of the groups with Ulmus davidiana powder. Springness in the control group was lower than that in the groups with Ulmus davidiana powder. But no significant difference in cohesiveness, gumminess and chewiness among groups was found. The intensity of color, odor and astringency of dasik with Ulmus davidiana powder significantly increased as the amount of supplementation increased(p<0.05). And the preference of flavor with 12% Ulmus davidiana powder was significantly lower than that of the control group. In conclusion, rice dasik with less than 9% of Ulmus davidiana powder would be most proper in taste and overall acceptability.

• Culinary science and hospitality research
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• v.16 no.3
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• pp.307-316
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• 2010

The principal objective of this study is to develop the optimal recipe for muffins prepared with replacement of sucrose with xylitol. The effect of xylitol on properties of muffins was evaluated in terms of height, volume, weight, specific volume, baking loss rate, crumbScan, colorimeter, sensory evaluation, and staling of muffins during storage days(0, 1, 3, 5 days) was measured by texture analyzer. Hardness of muffins was increased by adding xylitol, significantly during storage. Lightness(L value) of crust was increased significantly as the contents of xylitol increased. According to sensory evaluation, the muffins(control group) without xylitol had highest score in appearance and texture. In flavor, taste and overall acceptance, muffins with 25% of xylitol showed the best result but were not significant between the muffins(control group).

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.10
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• pp.1244-1250
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• 2014

The temperature of the main engine cabin of commercial vessel is very high. The material SS-316L undergoes creep damage at temperatures exceeding $450^{\circ}C$. It is essential to maintain the highly stressed engine cabin below the creep regime. Hence, seawater is employed in this kind of maritime vehicles as cooling liquid. It obtains the thermal energy at the cooling pipe line after passing through main engine cooling system. To harness the energy in the seawater, a turbine can be installed to absorb the energy in the seawater before being released into the sea. In this study, a cooling pipe line is selected to apply the tubular type hydro turbine for transferring the energy. Numerical analysis for investigating the performance and the internal flow characteristics of the tubular turbine is conducted. The results show that the maximum efficiency of 85.8% is achieved although the efficiency drops rapidly at partial flow rate condition. The efficiency descends slowly at the condition of excess flow rate. There is a relatively wide operating range of flow rate of this turbine to keep high efficiency at the excess flow rate condition. For the internal flow of the turbine, there is uniform streamline on the suction and pressure sides of the blade at the design point. However, the secondary flow appears at the suction and pressure sidesat the excess flow rate.In addition, it appears only at pressure side at the partial flow rate condition.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.316-319
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• 2012

In this paper, a novel particle swarm optimization method based on IE3D is used to design a mobile communication Microstrip Patch Antenna. The aim of the thesis is to Design and fabricate an inset fed rectangular Microstrip Antenna and study the effect of antenna dimensions Length (L), Width (W) and substrate parameters relative Dielectric constant (${\varepsilon}r$), substrate thickness on Radiation parameters of Band width. When the antenna was designed, a dual-band, dual-polarized antenna was used to secure the bandwidth and improve performance, and a coaxial probe feeding method so that the phased array of antenna is easy.