• Title/Summary/Keyword: 선구

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Analyses of Correlation Between Groundwater Movement and Tidal Effect in West Costal Landfill Area (서해안 매립지 내 지하수유동과 조석에 관한 상관성 분석)

  • Park Jong-Oh;Song Moo-Yaung;Park Chung-Hwa
    • The Journal of Engineering Geology
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    • v.16 no.3 s.49
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    • pp.293-300
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    • 2006
  • The groundwater movement in the west costal landfill area was analyzed by measuring N value by Standard Penetration Test, coefficient of permeability by falling head method, linear structure analysis by Digital Elevation Method, groundwater flow direction and rate by flowmeter logging due to tidal variation in the each borehole. The coefficients of permeability of the weathered zone and of the marine deposit showed similar values although some values of weathered zone show smaller values than those of the marine deposit. The major groundwater flow and rate in the marine deposit observed as east-west direction due to tidal variation, but on the other hand it was observed as N45E in weathered zone which is the major direction of the linear structures in the area. 2 hours delayed changes of the groundwater flow direction was observed during the 24 hours observation, and it seems to be a travel time of the tidal wave which cause the continuous change of the hydaulic gradient of the groundwater.

Intensity Analysis of the 26 June 1997 Kyongju Earthquake and Its Geological Significance (1997년 6월 26일 경주지진의 진도분석 및 지진 지질학적 의의)

  • 경재복;이희욱
    • The Journal of Engineering Geology
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    • v.8 no.1
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    • pp.13-23
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    • 1998
  • An intensity of the 1997 Kyungju earthquake(M=4.3) was estimated at three hundred locations based on the field survey and questionaires from 2200 residents. The isoseismal shows almost circular pattern which doesnot reflect some specific geological trends. However,most of the Kyeongsang basin except the southwestern part is included within the area of MM intensity V. There occurred strong shaking, numerous cracks on the wall of the houses, and movement of slate on the roofs, falling of the tiles from the monument. The isoseismal of the highest MM intensity VII, 1-3 km in width and 9 km in length, is elongated along the Yangsan fault, which is located about 1.5 km west from epicenter. The lineaments near the epicenter exhibit almost N-S and NNE directions. The lineament distribution, the pattern of damage area and the solution of fault plane suggest that the Kyongju earthquake occurred with strike-slip sense along the Yangsan fault. The calculated intensity attenuation(I) with distance(R) is as follows : $I{\;}={\;}I_o{\;}+{\;}0.3461{\;}-{\;}0.3274{\;}{\times}{\;}1nR{\;}-{\;}0.086{\;}{\times}{\;}R$.

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Soil Salinity Influencing Plant Stands on the Reclaimed Tidal Flats of Kyonggi-Bay in the Midwestern Coast of Korea (우리나라 중서부 해안 경기만 간척지에서 식생 분포에 대한 토양 염도의 영향)

  • Kim, Eun-Kyu;Chun, Soul;Joo, Young-K.;Jung, Yeong-Sang
    • Korean Journal of Soil Science and Fertilizer
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    • v.42 no.4
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    • pp.280-288
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    • 2009
  • To identify controlling factors for spatial variation of vegetation in reclaimed tidal flats, plant stands were investigated in a newly reclaimed as well as three matured tidal flats, and a natural tidal flat in the midwest coast of Korea. Electrical conductivity of saturated soil extract (ECe) was measured to assess soil salinity. Soil salinity differed significantly among plant stands. Depending on soil salinity, plant species showed different niches: glycophyte predominated low saline spots, halophyte predominated high saline spots. Soil salinity for each plant habitats was in order of as follow: bare soil or plant wilted > mixed pioneer halophyte > pioneer halophyte > mixed with pioneer halophyte and facultative halophyte > mixed facultative halophyte > facultative halophyte > mixed with facultative halophyte and glycophyte > glycophyte > mixed glycophyte stands. These results suggested that plant distribution might have been influenced by spatial edaphic gradient (soil salinity), and thus it could be utilized as an indicator for field soil salinity gradient. Relationship between soil salinity and plant distribution was not different among the aged reclaimed tidal flats, suggesting that the vegetative population might have changed into a similar direction since the reclamation.

Structure and Physical Properties of Earth Crust Material in the Middle of Korean Peninsula(4) : Development Status of Groundwater and Geological Characteristics in Chungnam Province (한반도 중부권 지각물질의 구조와 물성연구(4) : 충남도 지하수 개발 현황과 지질특성)

  • 송무영;신은선
    • The Journal of Engineering Geology
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    • v.4 no.2
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    • pp.153-168
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    • 1994
  • The status of groundwater development in Chungnam was studied with geological characteristics according to the measured data of Korean Rural Development Corporation. The data of 212 survey wells were used for the relation between catchment area and water discharge, and the data of 344 development wells for the relationships between well depth and discharge, between casing depth and discharge, between rock type and discharge, and the relation with lineaments density. The relationship between the catchment area and discharge does not show any special trend, and it is understood that groundwater of hard rock mass is not so much influenced by the surface catchment area. The relationship between well depth and discharge shows two different trends; discharge increasing with depth for alluvial groundwater, but no certain trend between depth and discharge for groundwater of hard rock zone. Discharge increases linearly with the casing depth, and it is reliable because the casing was installed in the weathered zone against well destruction. Generally the rock type does not show any difference of discharge, but the crystalline rocks such as granite and gneiss yield a little more discharge than the more porous rocks such as sedimentary rock or schist. It suggests that the effect of fracture zone is a major governing factor. In Hongsong and Puyo, there are similar in rock type and casing depth, but the big difference in average discharge. The big discharge of Hongsong is concordant with the higher intersection density and longer length of lineament in Hongsong than those of Puyo. Therefore the groundwater development strategy should be focused on the micro topography analysis and geophysical survey for the understanding of the fracture zone rather than catchment area or rock type.

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Inspection Techniques for Photovoltaic Equipments (태양광 발전설비 검사 기술)

  • Jung, Jong-Wook;Kim, Sun-Gu
    • Proceedings of the KIEE Conference
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    • 2009.07a
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    • pp.1072_1073
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    • 2009
  • This paper describes the inspection techniques for photovoltaic equipments. Firstly failure case studies on solar cells were presented, and then their FMEA was carried out. Lastly several core techniques as well as the contents by the inspection items on photovoltaic equipments were also expatiated.

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