• KOREAN ASSOCIATION OF OCCUPATIONAL HEALTH NURSES
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• v.4 no.3 s.13
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• pp.81-82
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• 1997

• Monthly Duck's Village
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• v.61 no.7
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• pp.16-16
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• 2008

• Proceedings of the Speleological Society Conference
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• 2004.11a
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• pp.33-40
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• 2004

• KOREAN POULTRY JOURNAL
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• v.35 no.2 s.400
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• pp.111-111
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• 2003

• The Korean Publising Journal, Monthly
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• s.281
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• pp.41-41
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• 2000

• Journal of the Korean association of regional geographers
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• v.14 no.1
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• pp.27-39
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• 2008

The propose of this research paper is to clarify the formative process of the lake-like swamps formed in channels of Nakdong-gang river and its tributary, Gumho-gang river. In order to understand the formative process of lake-like swamps, I compared topographical maps of three years(1918, 1962, 2005), analyzed the outline change of swamps, and draw their cross-sectional view and analyzed the horizontal distribution of particle size. Results of analysis are as follow. First, Saegang swamp and Geumgang swamps are residual swamps which are formed in abandoned distributary channels of braided reach. In braided reach, tributaries wind freely to create a new channel or to eliminate a old channel. Second, the Ssiksil swamp and Nat swamp are yazoo-type swamps. Their stream channels run parallel to the natural levees, as it blocks the waterway of a effluent tributary flowing from backward mountains to main stream. Third, the Secheon, Hochon and Jinchon swamps are backswamp behind natural levee. As main stream overflows, natural levee and back swamp are formed. Later flowing water of next bigger flood enter through natural levee into backswamp, create a channel following backswamp.

• Journal of the Korean GEO-environmental Society
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• v.11 no.5
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• pp.15-23
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• 2010

Dry sieving, wet sieving and photoscattering analyzer were tested as particle size analyzing methods for sediments from rivers and lakes of Han river, Nakdong river, Youngsan river, and Kumgang river area. Dry sieving showed a big error due to coagulating effect over drying process and this phenomena was severe for lake sediment. Wet sieving and PSA showed an accurate results though wet sieving needs more labor and complicate processes. Freeze-dry or freeze-dry after oxidation of organics with hydrogen peroxide showed improved results but gave lower portion of fine particles in comparing with wet sieving. Heavy metal contents and extractable metal contents were investigated for the sediments and high heavy metal content and extractable amount were obtained from fine particles as expected. Using of proper particle size analyzing method is important and the sediment management should be focused on the fine particles.

• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.481-481
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• 2016

하천퇴적물은 물의 순환과정에서 유역으로부터 유입되는 물질에 따라 조성이 변하게 된다. 특히 입자가 작은 토양과 유기성 물질들은 물순환과정에 이동성이 크게 나타나며, 인간에 의해 개발된 지역은 자연상태에 비해 이동하는 물질이 많이 나타나곤 한다. 본 연구에서는 하천에 건설된 보에 대한 퇴적물 조사를 실시함으로서 향후 수질관리에 필요한 기초 자료를 수집하고자 하였다. 본고에서는 금강과 낙동강에 건설된 보의 주요지점에 대한 퇴적물 조사를 실시하고 수질영향을 평가하였다. 조사는 홍수기전과 홍수기후로 구분하여 2회에 걸쳐 실시하였으며 물리적 성상과 화학적 항목에 대한 분석을 실시하였다. 입도분석 결과 금강 주요 10개 지점의 퇴적물 조성은 Sand, Silt와 Clay 성분이 혼합되어 있는 것으로 분석되었으며, 삼각좌표 분류법에 의한 토성은 대부분의 지점이 실트질양토(SiL)로 평가되었다. 완전연소가능량은 0.35~1.37로 전 지점에서 하천 호소 퇴적물 오염평가 기준의 유기물 함량기준 13%보다 높지 않은 것으로 나타났으며 홍수기 전 후에도 거의 유사하였다. 금강에서는 중금속뿐만 아니라 유기물 및 영양염류도 기준보다 낮게 나타났으며, 모든 항목에서 환경부예규인 하천 호소퇴적물 오염평가 기준보다 낮게 평가되었다. 하상 퇴적물이 수질에 미치는 영향을 평가하는 용출실험에서도 유기물 및 중금속 모두 수질에 미치는 영향은 거의 없는 것으로 평가되었다. 낙동강 주요 26지점의 입도분석 결과 퇴적물 조성은 대부분 Sand로 구성되어 삼각좌표 분류법에 의한 토성은 사토(S)로 평가되었다. 홍수기 전 후에 조사한 결과 완전연소가능량은 0.27~2.85으로 전 지점에서 하천 호소 퇴적물 오염평가 기준의 유기물 함량 기준보다 낮았으며 홍수기 전 후에도 거의 유사하였다. 화학적 성상 분석 결과 모든 항목에서 환경부예규인 하천 호소퇴적물 오염평가 기준보다 낮게 평가되었으며, 용출실험에서도 유기물 및 중금속 모두 수질에 영향을 거의 미치지 않는 것으로 평가되었다. 이번 조사는 4대강 건설 후 하상이 안정화 되지 않은 상태로 인해 지점간 특별한 경향성은 확인할 수 없었으며 보다 정확한 결과 도출을 위해서는 장기적인 조사를 통해 평가해야 할 것으로 판단되었다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.8
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• pp.83-92
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• 2019

This qualitative study employed focused group interviews to collect data on the forgetfulness experienced by elderly persons (over the age of 65) who suffer with subjective memory impairment. The participants were ten elderly persons who participated in the cognitive function improvement program at an elderly welfare center in D city. They were divided into three groups that were comprised of three/four people each, and each group was interviewed for 40~60 minutes. The results showed that "difficulties in human relations", "feeling uncomfortable in daily life", "exposure to a safety risk", "inexpressible ambivalence" and "family effort to overcome forgetfulness" were all expressed in the interviews. The elderly who participated in this study and who complained of subjective memory impairment had both feelings of anxiety and anxiety about non-dementia, and they were making efforts to overcome forgetfulness themselves. Based on this study, we suggest that interventions should be developed that reflect the individual needs of elderly people with subjective memory impairment.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.32 no.5
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• pp.323-331
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• 2019

In this study, a computational model approach for the modeling of hydrodynamic pressures acting on radial gates during strong earthquakes is proposed. The use of the dynamic layering method with the Arbitrary Lagrangian Eulerian (ALE) algorithm and the SIMPLE method for simulating free reservoir surface flow in addition to moving boundary interfaces between the fluid domain and a structure due to earthquake excitation are suggested. The verification and validation of the proposed approach are realized by comparisons performed using the renowned formulation derived by the experimental results for vertical and inclined dam surfaces subjected to earthquake excitation. A parameter study for the truncated lengths of the two-dimensional fluid domain demonstrates that twice the water level leads to efficient and converged computational results. Finally, numerical simulations for large radial gates with different curvatures subjected to two strong earthquakes are successfully performed using the suggested computational model.