• Proceedings of the Korean Society for Agricultural Machinery Conference
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• v.10 no.1
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• pp.72-75
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• 2005

사보니스 4익 풍차의 크기에 따른 토크, 회전수, 동력을 각기 다른 풍속에서 측정하였으며 열변환조의 회전수를 증가시키기 위하여 중속기어를 부착하여 풍력의 열변환시험을 하였다. 기어비 1:18 까지 증가시켜 로타의 회전수를 최고 180rpm으로 증가시켰지만 열변환능력은 크게 개선되지 않았다. 풍차의 크기와 동력의 관계에 관한 심층적 이론분석이 필요할 것으로 판단된다.

• Journal of Korea Fishing Vessel Association
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• v.71
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• pp.37-47
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• 1998

• The korean journal of orthodontics
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• v.37 no.3 s.122
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• pp.204-211
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• 2007

Objective: With an increasing demand for esthetic orthodontic appliances, the interest in polycarbonate brackets has also increased. However, polycarbonate bracket wings are prone to fracture. The purpose of this study was to evaluate the clinical usefulness of a newly-developed polycarbonate bracket by measuring the fracture strength of bracket tie wings. Methods: Alice (K.M. Daicom, Seoul, Korea) and Spirit MB (Ormco, Glendora, CA, USA) brackets were used as an experimental and control bracket respectively. Each bracket group was divided into halves. One half was untreated and the other half was treated with 2,000 times of thermocycling between $5^{\circ}C\;and\;55^{\circ}C$. The fracture strength of the wing was measured by a universal testing machine. Results: Alice bracket wings showed significantly higher strength than Spirit MB bracket wings in both untreated and thermocycled bracket cases. Conclusion: Alice brackets may be used clinically in terms of the strength of bracket wings.

• Journal of Energy Engineering
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• v.19 no.3
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• pp.195-202
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• 2010

A third of primary energy is lost as a waste heat. To improve this inefficient use of energy, systems using chemical reaction have been suggested and studied. In this study, methanol decomposition/synthesis reaction as a chemical reaction was selected for long time heat storage and long distance heat transport system because of safe, cheap and gaseous product. The purpose of this study is to find the optimal conditions in the methanol decomposition and synthesis reactions for long distance heat transport. Several parameters such as reaction temperature, pressure, $H_2$/CO ratio, space velocity, catalyst particle size were tested to find the effects on the reaction rates for the methanol synthesis. And the reaction temperature, space velocity, catalyst particle size were tested to find the effects on the production concentration for the methanol decomposition.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.5
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• pp.19-24
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• 2002

• Proceedings of the Membrane Society of Korea Conference
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• 2008.05a
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• pp.214-218
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• 2008

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.11a
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• pp.463-464
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• 2007

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2001.02a
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• pp.111-116
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• 2001

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.06a
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• pp.545-546
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• 2008

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.339-343
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• 2000

Rapid prototyping for welding and milling is a hybrid approach that makes use of welding as additive and conventional milling as subtractive technique. For two years this concept has been used to verify manufacturing mold and mechanical parts successfully. In latest new fabrication methods. For example, manufacturing mold for two sort of materials and shell fabrication, have been applied to the concept in KIST. This methods will be an alternative proposal in rapid prototyping. Metal deposition for welding causes the part to deform. It is a handicap in our proceeding. To overcome this problem, in this paper, we represent an optimal welding path for FEM analysis. Eight paths are tried to this and the value of deformation is average and standard deviation in four points'. Then we can compare with eight cases and select the optimal path.