• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.1036-1040
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• 2008

수질 개선을 위한 많은 노력과 투자를 하고 있다. 하지만 농경지의 부적절한 관리로 인한 토양유실로 발생하는 오염은 여전히 큰 비중을 차지하고 있다. 특히 강원도는 산이 많아 농경지의 대부분이 경사지에 위치하고 있다. 경사진 농경지는 그 특성상 토양유실이 일어나기 쉬운 조건에 있다. 경사지의 토양 유실은 지력을 저하시킨다. 또한 토양과 함께 유실되는 유기물 및 양분은 농경지의 손실이며 주변 수역으로 유입되어 수질 오염의 원인이 된다. 이런 토양 유실은 직접유출량과 큰 연관이 있다. 본 연구에서는 강우강도, 경사도, 피복도를 동일하게 조정할 수 있는 실내 인공강우 시험기를 사용하여 직접유출율을 산출하였다. 피복재료는 볏짚거적을 사용하였다. 강우강도는 30 mm/h와 60 mm/h 그리고 경사도는 10 %와 20 %를 사용하였다. 볏짚거적 피복처리는 0 kg/ha (나지), 3,000 kg/ha (볏짚 1겹), 6,000 kg/ha (볏짚 2겹), 10,000 kg/ha (볏짚 3겹) 이었다. 강우강도 30 mm/h, 경사도 10 % 인 시험포는 볏짚 1겹으로만 피복하여도 직접유출율이 0.77 %로 유출이 거의 발생하지 않았다. 강우강도 30 mm/h, 경사도 20 % 인 시험포의 직접유출율은 피복이 볏짚 1겹인 경우 16.9 %, 볏짚 2겹인 경우는 0 %로 매우 낮았다. 강우강도 60 mm/h, 경사도 10 % 인 시험포는 피복이 볏짚 2겹인 경우 3.4 % 로 매우 낮았다. 강우강도 60 mm/h, 경사도 20 % 인 시험포는 피복이 볏짚3겹인 경우 16.58 % 로 나타났으며, 볏짚 피복을 4겹 이상으로 할 경우 더 큰 저감 효과를 가져 올 수 있을 것으로 판단된다. 따라서 본 연구의 결과로 경사진 농경지의 직접유출량을 저감시켜 토양유실과 탁수를 줄이기 위한 방법으로 볏짚 피복을 선택하면 효과적인 것으로 사료된다.

• Spatial Information Research
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• v.17 no.3
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• pp.261-268
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• 2009

This study accomplished to draw a soil erosion map and a grade map of soil loss hazard in Korea. RUSLE and Rainfall-runoff (R) factor, which was estimated by using the rainfall data observed in 59 meteorological stations from 1977 to 2006 (for 30 years). FARD was used to analyze the frequency, and the whole country R factor was estimated according to the frequency. In the analysis of estimating the whole country R factor, Nakdong river has the smallest vaule, but Han river has the biggest value. According to the result of analyzing soil loss, soil loss occurred in a grass land, a bare land and a field in size order, and also approximately 17.2 ton/ha soil loss happened on the whole area. The average soil loss amount by the unit area takes place in a bare land and a grass land a lot. The total amount of soil loss in 5-year-frequency rainfall yields 15,000 ton and, what is more, a lot of soil loss happens in a paddy field, a forest and a crop field. The grade map of soil loss hazard is drawn up by classifying soil loss hazard grade by 5. As a result of analyzing soil loss, the moderate area which is the soil loss hazard grade 2 takes up the largest part, 72.8% of the total soil loss hazard area, on the contrary, the severe soil loss hazard area takes up only $1,038km^2$ (1.1%) of the whole area. The severe soil loss hazard area by land cover shows $93.5km^2$ in a bare land, $168.1km^2$ in a grass land and $327.4km^2$ in a crop field respectively.

• Journal of the Korean GEO-environmental Society
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• v.3 no.4
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• pp.19-27
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• 2002

Prediction of exact soil loss yield has as important engineering meaning as prediction of exact flow measurement in a stream. The quantity of soil loss in a stream should be considered in planning and management of water resources and water quality such as design and maintenace of hydraulic structures : dams, weirs and seawalls, channel improvement, channel stabilization, flood control, design and operation of reservoirs and design of harbors. In this study, the soil loss of Sap-gyo reservoir watershed is simulated and estimated by RUSLE model which is generally used in the estimation of soil loss. The parameters of RUSLE model are selected and estimated using slope map, landuse map and soil map by GIS. These parameters are applied to RUSLE's estimating program. And soil loss under probability rainfall in different frequencies are estimated by recent 30 years of rainfall data of Sap-gyo reservoir watershed.

• Spatial Information Research
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• v.2 no.2
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• pp.165-174
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• 1994

Soil loss was estimated by using universal soil loss equation(USLE) through GIS technique in Buyeu area. The expected soil loss is determined from six environmental factors: rainfall, erodibility of selected soil, length and steepness (gradient) of ground slope, crop grown in soil, and land practices used. A scoring system for assessing soil lossrisk has been developed for calculating SLI(Soil Loss Index) by GIS. The scores of six factors multiplied to give a total score which was compared with an chosen classification system to categorize areas of low, moderate and high risk. Finally, a soil loss assessment map was produced by GIS cartographic simulation technique, and this map could be applied in the establishment of regional land use planning.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.10a
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• pp.337-338
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• 2010

Projectile is said that objects thrown on the ground of the atmosphere. This objects exercises the parabolic motion because of the fact under the influence of gravity in the direction perpendicular and it does not include the horizontal force neglecting air resistance. In this paper, the experiment target is where subsidence occurred by that some of the road is lost to a certain depth using projectile motion. It says how far away and falling from the edge of the road when you have gone over the edge of depressed road that a car was driving at a constant speed.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.7
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• pp.1331-1343
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• 2000

Through the integration of USLE and GIS, the methodology to estimate the soil loss was developed, and applicated to the Sacheon river in Gangrung. Using GIS, spatial analysis such as watershed boundary determination, flow routing. slope steepness calculation was done. Spatial information from the GIS application was given for each grid. With soil and land use map, information about soil classification and land use was given for each grid too. Based upon these data, thematic maps about the factors of USLE were made. We estimated the soil loss by overlaying the thematic maps. In this manner, we can assess the degree of soil loss for each grid using GIS. Annual average soil loss of Sacheon river watershed is 1.36 ton/ha/yr. Soil loss in forest, dry field, and paddy field is 0.15 ton/ha/yr, 27.04 ton/ha/yr, 0.78 ton/ha/yr respectively. The area of dry field, which is 4% of total area, is $2.4km^2$. But total soil loss of dry field is 6561 ton/yr, and it occupies 84.9 % of total soil loss eroded in Sacheon river watershed. Comparing with the 11.2 ton/ha/yr of an average soil loss tolerance for cropland, provision for the soil loss in dry field is necessary. Run-off and water quality of Sacheon river were measured two times in flood season: from July 24, 1998 to July 28 and from September 29 to October 1. As the run-off of the river increased, SS, TN, TP concentrations and pollutant loadings increased. SS, TN, TP loads of Sacheon river discharged during the 2 heavy rains were 21%, 39%, and 19% of the total pollutant loadings generated in the Sacheon river watershed for one year. We can see that much pollutants are discharged in short period of flood season.

• Journal of the Korean Association of Geographic Information Studies
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• v.14 no.4
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• pp.63-76
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• 2011

This study purposes to develop a model to analyze soil loss in estimating prior disaster influence. The model of analyzing soil loss develops the soil loss analysis system on the basis of Internet by introducing cloud computing system, and also develops a standalone type in connection with HyGIS. The soil loss analysis system is developed to draw a distribution chart without requiring a S/W license as well as without preparing basic data such as DEM, soil map and land cover map. Besides, it can help users to draw a soil loss distribution chart by applying various factors like direct rain factors. The tools of Soil Loss Anaysis Model in connection with HyGiS are developed as add-on type of GMMap2009 in GEOMania, and also are developed to draw Soil Loss Hazard Map suggested by OECD. As a result of using both models, they are developed very conveniently to analyze soil loss. Hereafter, these models will be able to be improved continuously through researches to analyze sediment a watershed outlet and to calculate R value using data of many rain stations.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.51-51
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• 2019

고랭지(해발고도 400m 이상)는 전국 밭 면적의 24.7%을 차지하고 있고 경사도가 15도 이상인 지역이 58.7%인 41,812ha에 달한다. 고랭지 농업은 주로 해발고도가 높은 산지의 경사지에서 이루어지고 있고, 대부분 작물 재배기간이 5월부터 9월까지 약 5개월 정도로 짧아, 나머지 7개월은 토양 피복이 이루어지지 않은 상태로 있어 토양유실 가능성이 높다. 이러한 문제점을 개선하기 위해 본 연구에서 경관성이 높은 구절초를 식재하여 토양유실 저감 효과를 구명하였다. 고랭지 경사도 55도 라이시미터(Lysimeter)에서 가로 1.2m에 세로 1.8m의 규격으로 시험을 수행하였다. 관행구로 나지(Control, TC) 대비 식재 당시 피복정도에 따라, 피복율 40%는 T1, 피복율 70%는 T2로 하여 총 3처리를 두었다. 구절초의 개화기(10월 1일) 피복율을 조사한 결과 대조구인 나지상태는 0%의 피복율인데 이에 반해 구절초 식재 처리구는 57~80%로 경사지 토양을 피복시키는 효과가 가장 높은 경향을 보였다. 경관작물인 구절초를 식재할 경우 나지 TC를 기준으로 유출량이 65~71%, 토양유실이 87~99% 감소되어 강우에 의한 토양유실 경감에 매우 효과적이었다. 또한, 유거수 탁도 저감 효과성이 뛰어났다. 따라서, 고랭지 경사지에 영년생 자원식물 중 경관성이 뛰어난 구절초를 식재함으로서 경사지 토양유실을 경감시킬 수 있고, 부가가치가 높은 고소득작물로 활용 가치가 높다.

• Journal of the Korean Geotechnical Society
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• v.19 no.2
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• pp.255-265
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• 2003

A series of laboratory tests were performed to evaluate engineering properties of geobag system which is used for urgent restoration of the collapsed roadbed. In this study, the suitable geobag size was proposed as 44cm wide and 66cm long, and the suitable filling ratio of geobag was also proposed as 80% through the static loading tests. Also a series of model tests were carried out to investigate the characteristics of the engineering behavior and the distribution of earth pressure of the geobag roadbed under static and dynamic loading.

• Journal of Cadastre & Land InformatiX
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• v.45 no.2
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• pp.57-70
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• 2015

Recently, soil erosion have been thickening from heavy rainfall according to climate change. These soil erosion is main reason to cause landslide, the water quality, agricultural counterproductivity and so on. Therefore, it is important to find out the main source area to cause soil erosion using geospatial data including DEM, soil map and land cover those are very sensitive to soil erosion modeling. This study evaluated soil erosion using RUSLE model. Hyoja 4-Dong and Pyonghwa 2-Dong among Wansan-Gu showed high as 10,869 ton/yr and 10,477 ton/yr respectively and Ua 2-Dong of Deokjin-Gu showed high as 17,603 ton/yr in soil erosion. And Hyoja 1-Dong and Pyonghwa 1-Dong among Wansan-Gu showed high as $1,485.7ton/km^2$ and $1,297.0ton/km^2$ respectively and Inhu 3-Dong of Deokjin-Gu showed high as $2,557.7ton/km^2$ in unit soil erosion that was applied to the evaluation of soil erosion potential. It is anticipated that achievement of this study can apply to forecast and prepare the risk of soil erosion and debris flow in urban area.