• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.478-478
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• 2017

소류천 빗물 집수 장치는 노지 밭작물의 관개용수 확보를 위해 상시 흐름이 있거나, 간헐적으로 유출이 발생하는 산간 소류천 또는 배수로에서 빗물을 집수하기 위한 장치이다. 본 연구는 빗물 집수 장치의 집수 능력을 확인하기 위해 인공 수로 시험 장치를 이용한 요인시험을 실시하였으며. 장수군 노하리 산간지의 소류천에 설치하고 2015년 8월 5일부터 11월 15일까지 유출량 및 집수량 그리고 강우량을 관측하였다. 인공 수로 시험 장치를 이용하여 확인한 빗물 집수 장치의 최대 집수 가능량은 약 0.0022 ton/sec(130 L/분)로 나타났다. 빗물 집수 장치는 강우시에만 유출이 발생하는 지점(P1)과 상시 유출이 발생하는 지점(P2)에 설치하였고, 연구기간동안 총 강우량은 334.5 mm가 발생하였다. P1 지점에서는 총 1,722 ton의 유출이 발생하였으며, 273 ton이 집수되었고, P2 지점에서는 총 7,984 ton의 유출이 발생하였고, 125 ton이 집수되었다. 총 유출량 기준 집수 효율은 P1과 P2에서 15.85%, 1.57%로 산정되었고, 최대 집수 가능량 (0.0022 ton/sec)을 기준으로 한 집수 효율도 17.64%와 2.12%로 비교적 낮게 나타났다. 현장에서 빗물과 함께 발생하는 토사 및 부유물질 등에 의한 유입부 막힘이 집수 효율을 낮추는 주요 원인으로 분석되었다. 그러나, 월평균 총집수량은 약 30 ton 이상의 빗물을 저장할 수 있는 것으로 평가되어, 단기적인 물부족을 해소할 수 있는 대안으로 활용 할 수 있을 것으로 기대된다.

• Journal of Korea Spatial Information System Society
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• v.11 no.3
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• pp.1-8
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• 2009

In this study the concepts on the elongation, compactness and equivalent ellipse of catchment plan-forms are applied to the real basins considering their theoretical frameworks. The catchment plan-forms and corresponding equivalent ellipses, obtained from GIS, are inspected on downstream directions. As a result the catchment plan-forms seem to be the population of the basin shapes which come from the random interaction between two conjectures on Hack's law being controversial recently. The ratio of the maximum and minimum inertia moments of the catchment plan-form Ri is more sensitive to evaluate the elongation of the basin shapes than the ratio of the main channel length and diameter of circle which has the same area as the catchment plan-form E. The catchment plan-forms compactness measures show distinct aspects according to their different definitions. These results are caused by the difficulties to quantification of the shapes and the composite consideration with more than two compactness measures and the fractal analysis are therefore required to recover them.

• The Journal of Engineering Geology
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• v.29 no.2
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• pp.123-136
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• 2019

This study examines the effect of collector well installed to reduce groundwater level in the regions with the occurrence of landcreep, a soil mass movement triggered by instability on slopes. Slopes are prone to failure as a result of instability caused by its internal, topographic and geological properties as well as due to external factors such as rainfall and earthquake. In Korea during the rain season, rainfall infiltration affects the groundwater level in soil, building up porewater pressure and load, and finally drives slopes to collapse. Slope failure caused by rainfall infiltration has been leading to a drastic forest degradation. The studied slope is located adjacent to a valley, its terrain corresponds to piedmont gentle slope, while the upper part of the failure surface is steep. After reinforcing the terrain where landcreep had occurred and installing collector well on the slope, we measured the changes in the groundwater level. In order to analyze the relationship between the well and the slope, we calculated the ratio of groundwater level to rainfall before and after the installation of the collector well. As a result, it is confirmed that the ratio increases after the installation of the well, which in turn reduces the groundwater level. Analysis of the change in groundwater level after 3, 7, 15 days antecedent rainfall showed that the higher the overall groundwater level, the less the value ($r_p$) of groundwater level-rainfall ratio is, while the value becomes relatively greater when the groundwater level is low. In particular, if a slope has a large catchment basin as is in the case of the studied site, antecedent rainfall affects groundwater level in the order of 3 < 7 < 15 days.

• 한국상하수도협회지
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• s.15
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• pp.120-125
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• 2006

• Journal of architectural history
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• v.22 no.4
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• pp.35-44
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• 2013

This paper looked into the structure of and changes in the building process of Gijang mountain fortress and its receiving reservoir by analyzing data from an excavation investigation. The structure of the receiving reservoir may be classified into a flat form, stone sheath, floor facility, wall facility, and entry and exit facility. The flat form of the Gijang mountain fortress and receiving reservoir is round. Concerning the sectional form, the wall was obliquely excavated in the trapezoid. As a stone sheath building method, it was built by undertaking a range work of oblong stone materials in a clockwise direction on a stamped soil floor. Then, it was treated with stamping using double layers of gray clay and yellowish brown clay on the floor and the wall. Also, in a space between the stamped layers on the floor, herbal plants and a straw mat were laid for waterproofing as well as to prevent sinking. As an entry and exit facility, two facilities were confirmed symmetrically in the southeast and in the northwest. It is believed that they were built additionally during rebuilding after the initial construction. The building process was revealed to have been carried out in 8 stages. Given the structure and excavated remains, the building period is estimated to be the early to mid 7th century for the initial building, the later 9th to 11th centuries for the primary rebuilding, and the later 16th to early 17th centuries for the secondary rebuilding.

• The Journal of Engineering Geology
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• v.23 no.1
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• pp.1-17
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• 2013

It is sometimes necessary to change the location of the collection conduit, which is constructed in shallow sediments in a stream, if the concentrations of $Fe^{2+}$ and $Mn^{2+}$ become too high for water treatment. A total of nine wells, including four shallow wells with a depth of 3 m and five deeper wells with a depth of 6 m, were installed in the study area at Naeseong-cheon in Yecheon-gun. The change in hydrogeochemical features of groundwater and the concentrations of $Fe^{2+}$ and $Mn^{2+}$ were examined at the wells during 5 hours of pumping. As pumping was performed, the velocity of groundwater flow was increased around the pumping well and aeration conditions were developed to precipitate iron and manganese oxides in an oxidizing environment. In addition, the concentrations of $Ca^{2+}$ and $Cl^-$ at the pumping well were increased following the mixing of surface water and groundwater. It is suggested that the center region of the stream would be more suitable for a new collection conduit, considering the concentrations of $Fe^{2+}$ and $Mn^{2+}$ in groundwater and their reducing effect during pumping. The installation of a collection conduit based on field tests performed to ensure water quality enables a reduction in the construction and management costs at water treatment facilities.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.9
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• pp.623-629
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• 2012

The objective was to evaluate the quality of harvested rainwater of the roofing materials used and the presence of lichens/mosses on the roofing surface. This experiment was studied in the field where five pilot structures with different roofing materials (i.e., wooden shingle tiles, wooden shingle tiles (including mosses), concrete tiles, clay tiles [Gi-Wa] and slate tiles) were installed. As a result, the clay tiles [Gi-Wa] was found to be the most suitable for rainwater harvesting applications. It was due to the disinfection from ultraviolet light and high temperature according to characteristic of roofing materials. Comparison with quality of rainwater on that wooden shingle tiles with and without including mosses, which may affect the concentration of and wooden shingle tiles including mosses, mosses may affect concentration of TOC, nitrate, and sulfate. Additionally, the average concentration of asbestos was determined to be measured at $0.002/cm^3$ for the slate tiles. The value satisfied with it met the Ministry of Environment's Multi-use facility standard and Ministry of Labor's Office standard ($0.01/cm^3$).

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.854-858
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• 2008

최근 도시 및 단지 개발시 자연적인 물순환체계 구축에 대한 관심과 수요가 증가하고 있는 추세이다. 서울시를 비롯한 각 지자체에서도 빗물관리시설 적용과 관련된 조례를 제시하고 있으며, 건교부나 환경부에서도 수자원의 확보와 복원을 위한 빗물관련 법규 제정의 움직임을 보이고 있다. 또한 일부 지자체들은 도시 및 단지 개발시 빗물관리시설의 적용을 전제로 사업승인을 하는 등 수자원확보와 수순환복원을 위해 빗물관리에 대한 관심이 높아지고 있다. 특히 최근 문제시되는 물부족 현상에 대비해 대체수자원으로써 빗물의 저류와 침투를 통한 직 간접적인 활용은 수자원 확보에 있어 하나의 대안이 될 수 있다. 이에 본 연구에서는 공동주택단지를 대상으로 하여 빗물관리시설중 침투정과 침투트렌치 적용에 따른 유출저감효과를 분석하였다. 본 연구에서는 대상지점으로 표준이 될 수 있는 공동주택단지를 선정하고, 대상지점 내 적용이 가능한 곳에 기존 집수정과 우수관을 대신하여 침투정과 침투 트렌치를 가상으로 적용하였다. 침투정과 침투트렌치는 표준의 것을 적용하는 것으로 하고, '빗물 저류침투기술협회(일(日))'의 시설별 설계침투량 계산을 통해 침투정과 침투트렌치 적용에 따른 대상지점에 우수유출량을 합리식으로 계산하였다. 그리고 대상지점의 개발전 유출량과 개발후 유출량(집수정, 우수관적용), 개발후 유출량(침투정, 침투트렌치적용)의 비교를 통해 빗물관리시설의 적용에 따른 유출저감효과를 분석하였다.

• Journal of Korea Water Resources Association
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• v.45 no.7
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• pp.643-656
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• 2012

There has been an increase for the landslide areas and restoration expenses due, in large part, to the increased locally heavy rains caused by recent climate change as well as the reckless development. This study carried out a slope stability analysis by the application of distributed wetness index, using the GIS-based infinite slope stability model, which took the root cohesion effect into consideration, for part of Mt. Umyeon in Seoul, where landslide occurred in July 2011, in order to compensate the defects of existing analysis method, and subsequently compared its result with the case on the exploitation of lumped wetness index. In addition, this study estimated the distributed wetness index by methodology, applying three methods of specific catchment area calculation: single flow direction (SFD), multiple flow direction (MFD), and infinity flow direction (IFD), for catchment area, one of the variables of distributed wetness indices, and finally implemented a series of comparative analysis for slope stability by methodology. The simulation results showed that most unstable areas within the study site were dominantly located in cutting-area surroundings along with the residential area and the mountaintop and unstable areas of IFD and lumped wetness index method were similar while SFD and MFD provided smaller unstable areas than the two former methods.

• Journal of Conservation Science
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• v.37 no.5
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• pp.536-544
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• 2021

In the present study, safe management and value improvement of bamboo sunblind, which is an item of cultural heritage, were performed by adopting stable conservation treatment methods. The bamboo sunblind used in the present study was excavated from No. 1 catchment site in Baesanseongji, Busan. It was determined that the main material used to make the sunblind was bamboo, and herbal plants were used to weave the bamboo using lacquer as an adhesive agent. All contaminants and soil adhered to the sunblind was removed. Thereafter, the sunblind, which was recovered in the form of blocks, was washed separately after fixing it to a temporary plaster frame and to avoid the blocks from breaking during washing. Then, polyethylene glycol (PEG) impregnation was utilized for the reinforcement treatment. Based on the preliminary test results, the shape of the sunblind was fixed using a stainless-steel frame to prevent physical damage that may occur during the drying process. Thereafter, the bamboo sunblind was vacuum freeze-dried. PEG 20% (in ethyl alcohol) was applied as a surface treatment agent for stabilization the sunblind. After the surface treatment, the bamboo sunblind were joined together to fit the maximum width, and the rectangular shape of the sunblind was restored-as best as possible-while filling in the missing parts by maximizing the use of unknown members such as in the disturbed layers below bamboo sunblind surface. The conservation treatment was completed by fixing the bamboo sunblind into the fabricated frame.