• Journal of Ocean Engineering and Technology
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• v.12 no.1
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• pp.3-9
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• 1998

According to the developement of cities, electric wires and commuinication lines which are currently above the ground effect on the bad. Nowadays, it is necessary to build up underground facilities because the construction is increasing. Excavation work has been dominant even though the inconvenient things occurred, for example a civil appeal, a traffic obstacle, safety and spoiling the fine view because of the cost or period of the construction work. But the congestion of cities are more and more serious. Therefore shield-method is the way to escape from congestion. I considered all the construction fields which are in progress or finished.

• Journal of Sericultural and Entomological Science
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• v.29 no.1
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• pp.39-47
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• 1987

The incidence of mulberry dwarf disease was surveyed on seventy two cocoon producing areas throughout the country from 1983 to 1984. There was a low tendency of incidence in Gyeonggi, Gangwon and Chungbuk, the northern parts of 37 degrees north latitude. However, in Chungnam and Gyeongnam, was a relatively high incidence observed. The most severe incidence areas of mulberry dwarf disease were found in Jeonnam, Jeonbuk and Gyeongbuk.