• Proceedings of the Korean Society of Propulsion Engineers Conference
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• v.y2005m4
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• pp.225-230
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• 2005

It is theoretically known that recuperator can bring a significant increase in thermal efficiency of the gas turbine unit, but it also has disadvantages such as pressure loss in the flow channel, thermal stress and increase in weight. Therefore it is necessary to consider all pros and cons of this equipment in view of economic aspects throughout its life cycle. Recuperator has been applied mostly in the power ranges of $20\sim300kW$ class industrial units but hasn't been used as a larger power generation unit except for naval applications in mid twentieth century. Present paper considered the applicability of a recuperator cycle in term of pressure loss, part load aspects for power generation purpose.

• The Korean Journal of Pesticide Science
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• v.6 no.3
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• pp.175-182
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• 2002

This experiment was conducted to investigate the effects of acid rain in spraying copper hydroxide 77% wettable power(WP) on leaf surface morphology and crop injury of the garlic(Allium sativum L.). Leaf chlorosis, hooked leaves, wrinkled epidermal cells and increased stomata open of garlic were induced by foliar application of simulated acid rain(SAR). It was become to be severe in application of copper hydroxide solution after application of SAR, but those yield of garlic was not significantly different from the untreated control. Leaf chlorosis was sharply increased above 100 ppm of copper ions. Amount of solved copper ions in copper hydroxide solution was remarkably increased below pH 5.5 and the residue in garlic leaves was significantly increased by application of copper hydroxide solution after spraying SAR compared with application of copper hydroxide solution only. When calcium carbonate was applied together with copper hydroxide leaf chlorosis was less than copper hydroxide only.

• Journal of the Korean Society of Propulsion Engineers
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• v.3 no.2
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• pp.48-55
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• 1999

Performance analysis of a 50KW turbo-generator gas turbine engine with a recuperator was studied. Recuperated cycle has been employed to meet maximum fuel economy and ultra low emissions especially for military and vehicular engines. From thermodynamic stand point, it is known that recuperative cycle can contribute most to enhance thermal cycle efficiency for the Pressure ratios under 10 and of comparatively low turbine inlet temperature. Efficiency of a simple cycle with a recuperator increases relatively about 30% than without one at effectiveness of 0.5. Pressure losses in the heat exchanger less than 5.2% is considered in the design process. A tubular type heat exchanger is selected for this particular engine because it can provide simple construction as well as structural sturdiness and excellent leak tightness.

• 보일러설비
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• s.71
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• pp.93-96
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• 1999

• The tire
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• s.226
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• pp.40-41
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• 2006

• Korea Petroleum Association Journal
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• no.4 s.26
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• pp.13-15
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• 1983

• The tire
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• s.225
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• pp.45-48
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• 2005

• The tire
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• s.223
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• pp.28-30
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• 2005

• Research in Plant Disease
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• v.10 no.4
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• pp.297-303
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• 2004

Bacterial blossom blight of kiwifruit (Actinidia deliciosa) has been mainly controlled by antibiotics. Among 15 candidate chemicals, streptomycin sulfate oxytetracycline WP, streptomycin copper hydroxide WP and oxolinic acid WP were selected as preventive bactericides against bacterial blossom blight of kiwfruit through in vitro and in vivo test. Spray of streptomycin sulfate oxytetracycline WP and streptomycin copper hydroxide WP at flowering period was most effective in controlling bacterial blossom blight of kiwifruit. Among the various combinations of spray times at different spray periods, optimum spray program of the preventive bactericides for the control of bacterial blossom blight of kiwifruit was turned out to be 3 times application with 10 day-interval from early May during the flowering season of kiwifruits.

• Journal of the Korean Magnetics Society
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• v.22 no.2
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• pp.66-72
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• 2012

The findings of ferromagnetic superconductor have attracted much attention not only for fundamental research to investigate how the antagonistic properties of ferromagnetism and superconductivity coexist peacefully but also for potential technological applications. Firstly, in order to help for understanding the ferromagnetic superconductor, I have explained the orbital and paramagnetic pair-breaking effects of magnetic field, which breaks the superconducting Cooper pairs. In addition to such effects of magnetic field, the singlet Cooper pairs become unstable upon going through the ferromagnetic materials by the proximity effect. The proximity effect occurs at the interface of thin films composing of superconductor and ferromagnet and leads to have very short penetration depth of Cooper pairs. However, a type of odd-frequency triplet in comparison with the singlet could be very stable and has a longer effective depth. It needs to be explored for the innovative spintronic devices. Finally, various ferromagnetic superconductors coexist and the lower-dimensional materials under the Quantum confinement effect have been introduced.