• The Journal of the Petrological Society of Korea
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• v.23 no.2
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• pp.75-103
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• 2014

The Quaternary faults are extensively observed along major inherited fault zones (i.e. Yangsan Fault System, Ulsan Fault, Yeonil Tectonic Line, Ocheon Fault System) in SE Korea. Their geometry and kinematics provide a very useful piece of information about the Quaternary crustal deformation and stress field in and around Korean Peninsula. Using magnetic fabrics (AMS), we attempted to determine the slip senses of Jinti, Mohwa, Suseongji2, and Wangsan faults and then interpreted the fabric development process of fault gouge and the characteristics of stress field during the Quaternary. All the magnetic fabrics of the faults, except the Wangsan Fault, consistently indicate a dominant reverse-slip sense with weak strike-slip component. Most of the oblate fabrics are nearly parallel to the fault surface and the anisotropy degrees generally increase in proportion to the oblatenesses. These results suggest that the fabrics of the fault gouges resulted from a progressive deformation due to continuous simple shear during the last reactivation stage as reverse faulting. It is also interpreted that the pre-existing fabrics were overwhelmed and obliterated by the re-activated faulting. Paleostress field calculated from the fault slip data indicates an ENE-WNW compressive stress, which is in accord with those determined from previous fault tectonic analysis, focal mechanism solution, and hydraulic fracturing test in and around Korean Peninsula.

• Journal of the Korean Society of Groundwater Environment
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• v.2 no.2
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• pp.64-71
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• 1995

Electrical soundings were conducted in and around the Nanjido waste landfill in August, 1994 and February, 1995. Schlumberger array was adopted and 37 and 22 soundings were performed around and in the Nanjido landfill, respectively. Besides, self potentials were measured at 50 points, in front of the right Nanjido landfill. Interpretations of the sounding data show low resistivity zones of about 10 Ω-m at depth ranging from 10 to 80 m from the surface in front of the landfill and of about 6 Ω-m at depth ranging from 37 m to 130 m in the landfill. It appears that these low resistivity zones are contaminated by or saturated with leachate, and their depths are deeper than those of boring data by 20∼30 m. These results indicate the possibility of contamination of weathered zone and the upper part of the bed rock in these areas. But sounding data obtained at the back of the landfill reveal more resistive and thinner low resistivity zones than those in and in front of the landfill. Thus it is concluded that the degree of contamination by leachate in and in front of the landfill is greater than that at the back of the landfill.

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.7-12
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• 1999

The effects of antioxidants, ascorbyl palmitate (AP), ${\alpha}-tocopherol\;({\alpha}-Toc)$, BHA and ascorbyl $palmitate+{\alpha}-tocopherol\;(AP+{\alpha}-Toc)$ have been investigated on lipid peroxide formations in tallow immediately and during storage at $50^{\circ}C$ after gamma irradiation with the dose of $1{\sim}10kGy$. Immediately gamma irradiation greatly increased the initiative oxidation of tallow as was expected. But antioxidants were found to be greatly effective in minimizing the radiation-induced peroxidation of tallow and their antioxidative activities were $AP>BHA>AP+{\alpha}-Toc>{\alpha}-Toc$. Especially, AP showed greater antioxidative activity of initiate-oxidation than that of any other antioxidant. Oxidation of tallow during storage at $50^{\circ}C$ after irradiation induced the accelate of autoxidation. But the additions of antioxidants inhibited formation of peroxide. Their antioxidative activities were $BHA>AP+{\alpha}-Toc>{\alpha}-Toc>AP$. Especially $AP+{\alpha}-Toc$ mixture was not significantly different from BHA (p>0.05).

• Journal of Korean Tunnelling and Underground Space Association
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• v.17 no.3
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• pp.383-392
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• 2015

In subsea tunnelling, prediction of the fractured zone (or water bearing zone) ahead of tunnel face saturated by seawater with high water pressure has been a key factor for safe construction. This study verified the feasibility of utilizing induced polarization (IP) survey at tunnel face for predicting the ground condition ahead of the subsea tunnel face. A pore model was proposed to compute chargeability in granular material, and the relationship correlating chargeability with the variables affecting the chargeability was derived from the model. Parametric study has been performed on the variables to figure out the most influential factors affecting the chargeability. The results of the parametric study show that the size of narrow pores ($r_1$) and the salinity of pore water are the most influential factors on chargeability. Laboratory tests were conducted on various types of ground condition by changing the salinity of pore water, the thickness of the fracture zone and the existence of gouge (weathered granite) within the joints of the fractured zone to figure out the effect of the ground characteristics on the IP phenomenon. Test results show that the chargeability of the fractured zone saturated by seawater increases if the joints in the fractured zone are filled with gouge since the infilled gouge will decrease the size of narrow pores ($r_1$).

• Korean Journal of Agricultural Science
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• v.17 no.2
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• pp.130-141
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• 1990

In order to investigate possible utilization as a naturall antioxidant, antioxidative fraction from pueraria root powder was obtained by solvent extraction. PO,CO and TBA values were measured at $60^{\circ}C$, $100^{\circ}C$, $145^{\circ}C$, respectively, after adding the pueraria root extract to the final concentration of 0.1% to the lard, beef tallow, pallm and soybean oil. The results of antioxidative effect of pueraria root extract to edible oils and fats were as follows : 1. Antioxidative fractions in pueraria root were extracted by sequential solvent systems using ethanol, methanol : isopropyl alcohol (1: 4) and chloroform : methanol(95 : 5). 2. Antioxidative activity of the extracts to edible oils and fats was more effective than that of adding 100 ppm $\alpha$-tocopherol at $60^{\circ}C$. 3. At $60^{\circ}C$ and $100^{\circ}C$, antioxidative effect was beef tallow>palm oil>lard>soybean oil in its orders. 4. At $145^{\circ}C$, the pueraria root extract showed antioxidative activity in beef tallow, lard and palm oil, but not in soybean oil. 5. The content of saturated fatty acids by the heat treatment was remained smalll change, but that of unsaturated fatty acids was noticeable decreased.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.3
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• pp.380-389
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• 2020

The conversion characteristics and fuel properties for producing biodiesel (BD) by blending beef-tallow, an animal waste resource with a high-saturated fatty acid content, and sunflower-oil, a vegetable oil with a high-unsaturated fatty acid content, were investigated. For this investigation, the effects of the control factors, such as the oil-blend ratio and methanol-to-oil molar ratio, on the fatty acid methyl ester and BD production yield were also investigated. The kinematic viscosity reduction effects of BD using heating and ultrasonic irradiation were verified, and the optimal temperature of each BD-diesel fuel blend for reducing the kinematic viscosity was derived using the correlation equation. As a result, the optimal conditions for producing blended biodiesel were verified to be TASU7 and a methanol-to-oil molar ratio of 10:1. The analysis results of the fuel properties of TASU7 satisfied the BD quality standard; hence, the viability of BD blended with waste tallow as fuel was verified. The experimental results on the kinematic viscosity reduction showed that heating is more effective in reducing the kinematic viscosity because it took less time than ultrasonic irradiation, and the equipment was cheaper and more straightforward than the ultrasonic irradiation method.

• Korean Journal of Food Science and Technology
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• v.26 no.5
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• pp.567-572
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• 1994

Diglyceride was prepared by reaction of hydrogenated beef tallow and glycerol (GL) in the presence of a Pseudomonas lipase. Both substrates were mixed at the ratio of GL/Triglyceride of 0.5 which is the stoichiometric molar ratio for the complete conversion of triglyceride (TG) to diglyceride (DG). DG can be obtained by solid phase-glycerolysis of hydrogenated beef tallow without use of organic solvents or emulsifiers by careful control of reaction temperature. Optimized reaction temperature condition was as follows: An initial incubation at$60^{\circ}C$ for 2h followed by the first temperature shift down to $55^{\circ}C$ for 4h, and then the second shift down to $50^{\circ}C$ for up to 3 days. There was a large decrease in the content of TG during the first $60^{\circ}C$ incubation for 2h. Even a prolonged incubation at $60^{\circ}C$ could not make a change of the composition of the reaction mixture at liquid state. By controlling the temperature lower than $60^{\circ}C$, reaction mixtures were solidified. The reaction temperature at $50^{\circ}C$ below the melting temperature of hydrogenaed beef tallow gave an 71% optimum yield of DG after 72h enzymatic glycerolysis and about 73% of total DG was 1,3-DG.

• Communications of the Korean Institute of Information Scientists and Engineers
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• v.22 no.7
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• pp.13-21
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• 2004

화약 냄새가 자욱한 전장의 막사에서 취침하려는 나폴레옹은 매일 같은 지시를 하고 잠들었다고 한다. "좋은 소식은 깨우지 말고, 나쁜 소식은 깨우라." 그는 속도의 중요성을 인지한 리더였다. 2003년 우리는 마젤란 시대에 비하여 240배 빠르게 살고 있다. 초속 3백m의 점보기가 10시간에 가로지르는 태평양을 마젤란은 1520년에 약 1백일 간의 항해로 횡단하였다.항해로 횡단하였다.

• KOREAN POULTRY JOURNAL
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• v.7 no.8 s.70
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• pp.61-66
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• 1975

앞으로의 국제사료곡물 시세 및 국내 주요 단미사료 시세에 큰 변동은 없을 것 같다. 만약 곡물 시세를 변동시킬 만한 요인이 있다면 현재 강세를 보이고 있는 강류사료 가격의 여하와 소련의 구매량과 구매시기, 미국의 주산지 기상조건 및 그 외 곡물 수출국가의 수출여력과 수요국가의 수요도 여하에 따라 결정지어 질 것으로 전망된다. 그리고 관세제도의 변경실시로 옥수수, 수수, 타피오카 이외의 품목은 관세가 부과되므로 특히 고열량사료인 우지 등의 수입이 어렵게 되었다. 또 배합사료 가격안정기금 확보를 위한 수입사료 부담금적립 등의 문제가 있겠으나 전반적으로 밝은 전망이다. 이러한 때를 놓치지 말고 우리 축산인 모두가 서로 협력하여 축산업의 안정적 발전을 위하여 총매진해야 겠다.

• The Optical Journal
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• s.119
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• pp.60-64
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• 2009

최근 전자 광정보통신시스템의 급속한 고성능화 다기능화로 상징되는 것처럼, 기능성 재료의 물성을 십분 발휘하여 초고성능부품을 제조하기 위해서는 초정밀가공기술이 필수이다. 여기에서 말하는 초정밀가공조건에는 통상, 무료란(결정공학적으로 원자배열에 교란이 없는)경면, 게다가 나노미터오더의 형상정도여야 하는 것이 대전제가 된다. 본 고에서는 초정밀가공기술을 구사한 가공공정 중에서, 가장 미세한 가공면을 얻을 수 있는 유리지립 가공의 초정밀폴리싱/CMP기술과 그 응용사례에 관해 서술한다.