• 기계와재료
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• v.12 no.4 s.46
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• pp.80-96
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• 2000

• Journal of the korean veterinary medical association
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• v.27 no.6
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• pp.349-354
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• 1991

• Landscaping Tree
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• v.7 no.3_4
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• pp.54-55
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• 1992

• 전기의세계
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• v.31 no.11
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• pp.766-770
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• 1982

본고의 내용은 다음과 같다. 1. 전력계통의 개요 2. 급전시스템의 개요 3. 여섯번째 설립한 컴퓨터제어 시스템 4. 신 제어소 5. 원격소의 설비

• 동위원소뉴스
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• no.1 s.49
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• pp.1-1
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• 2001

• Radioisotope journal
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• v.15 no.1
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• pp.28-30
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• 2000

• 동위원소뉴스
• /
• no.5 s.17
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• pp.1-1
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• 1998

• The Korean Journal of Archival Studies
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• no.3
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• pp.187-199
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• 2001

• Korean Journal of Mineralogy and Petrology
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• v.33 no.3
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• pp.185-193
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• 2020

There have been many studies on the calcination of oyster shells in the perspective of recycling of resources. The quicklime made by the calcination of oyster shells is used either as it is or after reacting with water to transform to liquid lime before being used. However, the liquid lime made from calcined oyster shells show slightly different properties from that of limestone. In this study, to compare these properties of oyster shell with those of limestone, the samples were calcined and reacted with water at various temperatures to transform to a liquid lime and filtered using 150 ㎛ sieves to calculate the transform rate to liquid lime. The calcined limestone was transformed to liquid lime at all temperatures, but calcined oyster shell did not show any transformation at 30℃ and 50℃ under the experimental conditions of this study, and rather increased the weight for the remaining after filtration due to the presence of Ca(OH)₂ produced by the reaction with water, Even at 90℃, the transformation rate of calcined oyster shell to liquid lime was lower than that of limestone. This difference in oyster shell can be explained partly by the preventing calcined one from reacting with water by conchiolin which is protein found in the prismatic and pearl layers of oyster shell. Conchiolin is also known to be stable and does not decompose even at high temperature. However, even the calcined chalk layer without conchiolin shows lower transformation rate than that of calcined limestone, probably due to the small amount of Na in oyster shell, which may cause additional reaction including eutectic melt during calcination process.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.29 no.3
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• pp.237-247
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• 2011

As of 2011, 72 Permanent GPS Stations are installed to control DGPS reference points by the National Geographic Information Institute in South Korea. As the center of the Earth's mass continues to move, the coordinates of the permanent GPS stations become inconsistent over time. Thus, a reference frame using a set of coordinates and their velocities of a global network of stations at a specific period has been used to solve the inconsistency. However, the relative movement of the permanent GPS stations can lower the accuracy of GPS relative positioning. In this research, we first analyzed the data collected daily during the past 30 months at the 40 permanent GPS stations within South Korea and the 5 IGS permanent GPS stations around the Korean Peninsula using a global network adjustment. We then calculated the absolute and relative amount of movement of the GPS permanent stations. We also identified the optimum renewal period of the permanent GPS stations considering the accuracy of relative GPS surveying. Finally, we developed a Korean a Korean crustal movement model that can be used to improvement of accuracy.