• Journal of Korea Water Resources Association
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• v.40 no.5
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• pp.397-407
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• 2007

The deposition of sewer solids during dry weather in combined sewer systems results in a loss of flow capacity that may restrict flow and cause a local flooding and enhanced solids deposition. In order to solve these problems and to manage sewer systems efficiently, development of estimation equations for solid sediments In sewer systems is needed. However, estimation of solid sediments has performed using specific methods such as computer model before the development of estimation equations. In this study, solid sediments in sewer systems were estimated using MOUSE model for Gunja drainage basin in Korea and the estimated results were verified using estimation equations developed by the U.S. Environmental Protection Agency. As results, the estimated values using MOUSE model are smaller than that of equations developed in 1977 but greater than that of equations developed in 1984. Although the comparison between simulated and measured solid deposition is difficult due to the absent of measurement data, the estimated values using MOUSE model is reliable and can be used to develop estimation equations for solid sediment in Gunja drainage basin.

• Journal of Korea Water Resources Association
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• v.40 no.5
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• pp.409-418
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• 2007

Combined sewer solid deposition during dry weather periods and their resuspension during wet weather periods has long been recognized as a major contributor to the first-flush phenomenon. Also, these deposition of sewer solids results in a loss of flow capacity that may restrict flow and cause a local flooding at urban area. In order to solve these problems, measurement of solid deposition for a given sewer system for extended period is needed but this task is very difficult and extremely expensive. This paper presents the development and applicability of estimation equations for solid deposition in sewer systems based on the solid deposition estimated using MOUSE model. As results, the comparison between estimated and measured solid deposition is difficult due to the absent of measured data, but the estimated values using developed equations show applicability compared with the results of MOUSE model and the estimation equations developed by the EPA.

• Journal of Korea Water Resources Association
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• v.41 no.9
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• pp.885-894
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• 2008

The deposition of solids in combined sewer systems results in a loss of flow capacity that may restrict flow and cause a local flooding and enhanced solids deposition. In order to solve these problems and proper pipe management, estimations of solid loads on land surface in a drainage basin and solid deposition in sewer system due to rainfall are needed but these tasks are very difficult and very expensive. In this study, procedures for estimating solid loads on surface in a drainage basin were applied and analyzed in Gunja drainage basin in Korea. Also, this paper presents the development and application of estimation equation for solid deposition in sewer system due to rainfall based on the solid deposition estimated using MOUSE model. As results, the comparison between estimated and measured solid deposition is difficult due to the absent of measured data, but the estimated values using developed equations show applicability compared with the results of MOUSE model and the application of the other basin. The developed estimation equations can be used usefully for the management of combined sewer system.

• Journal of Korean Institute of Industrial Engineers
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• v.39 no.3
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• pp.163-171
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• 2013

Various web browsers offer mouse gesture functions because they are convenient input methods. Mouse gestures enable users to move to the previous page or tab without clicking its relevant icon or menu of the web browser. To maximize the efficiency of mouse gestures, they should be designed to match users' mental models. Mental models of human beings are used to make accurate predictions and reactions when certain information has been recognized by humans. This means providing users with appropriate information about mental models will lead to fast understanding and response. A cognitive response test was performed in order to evaluate whether the mouse gestures easily associate with their respective functional meanings or not. After extracting mouse gestures which needed improvement, those were redesigned to reduce cognitive load via sketch maps. The methods presented in this study will be of help for evaluating and designing mouse gestures.

• Journal of Korean Society of Water and Wastewater
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• v.24 no.5
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• pp.549-560
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• 2010

Recently, heavy rainfalls due to the climate change in Korea have caused inundation problems in urban sewer networks. In july 2006, a flooding accident at Misari motorboat racing stadium near the Han river occurred due to the effect of record-breaking outflow discharge from Paldang-dam. The purpose of this study was to simulate and analyze the flooding accident at Misari stadium by MOUSE model. The results of simulation analysis indicated that the total flood volume was $1,313,450m^3$. The effect of back water was 85.9% of the total volume which was caused by the manhole accident, and the effect of accumulated runoff was 14.1% of total volume which was caused by non-return valve shutdown. The simulation results of this MOUSE modeling that was linked to the boundary condition of the dynamic flows in the river by DWOPER model showed the potential of successful inundation analysis for sewer networks.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.1701-1705
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• 2010

최근의 기후변화로 인한 각종 관측 기록들과 여러 가지의 기후전망에 따르면 강한 강우사상으로 인한 극심한 홍수 또는 가뭄의 위험을 초래하고 있으며 이는 전 세계적으로 발생하는 문제이기도 하다. 기상이변에 의한 집중호우와 그밖에 도시 개발로 인한 유출량의 증가로 인해 홍수피해가 점점 늘어나고 있으며, 극심한 강수 부족에 의한 가뭄의 피해도 발생한다. 이러한 피해의 근본적인 대책이 없다면 어떠한 형태로 발생할지 모르는 물 관련 재해에 효과적으로 대처할 수 없을 것이다. 본 연구에서는 도시유출해석모형인 MOUSE를 이용하여 상습 침수 지역이었던 소래포구 지역의 지표면 유출량을 통한 관망해석을 실시하였으며, 50년 빈도의 가장 불리한 해석조건인 임계지속시간을 산정하여 연구 대상지역에 적용하였다. 연구 대상지역의 우수저류조 설치 전과 후의 관망 내 수위 및 첨두유량 변화를 비교한 결과, 우수저류조 설치 유무에 따라 수위 및 첨두유량에서 저감 효과가 나타나는 것을 볼 수 있었다.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.237-241
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• 2006

최근에 들어 도시지역에서는 국지성 집중호우에 의한 홍수피해가 증가하는 경향이 있으며, 우수설비 시스템이 비교적 갖추어진 개발 지역에서도 기존의 우수설비시스템의 용량이 초과되어 큰 침수피해가 발생하고 있다. 홍수규모가 배수시스템의 용량을 초과할 경우 건물, 공공기반시설 등 재산 및 인명 등에 있어 많은 피해를 야기하고 있으며, 도로의 침수는 운송 시스템의 기능에 문제를 일으키게 되어 도시의 산업과 기능을 마비시킨다. 이러한 도시지역 홍수에 대비하여 도시지역의 복잡한 지형 형상과 인위적 배수시스템을 함께 고려하여 해석할 수 있는 침수해석모형의 개발이 필요하다. MOUSE와 SWMM(Storm Water Management Model) 계열 모형들(EPA SWMM, MIKE SWMM, XP SWMM, PC SWMM)(Huber and Dickinson, 1988)은 도시유출해석에 많이 이용되고 있다. 그러나, 이들 모형들은 과부하된 유입구에서의 범람되는 홍수유량곡선만을 제공하며 지표면 범람 지역, 수심, 및 침수기간에 대한 상세한 정보를 제공하지 못한다. 따라서, 도시배수체계모형과 도시침수모형에 대해 상호연계를 수행할 수 있는 새로운 도시범람 모형이 도시지역에서 홍수로 인한 침수해석을 모의하는데 필요하다. 배수시스템 해석 모형의 계산결과를 이용하여 침수해석을 수행하는 연계모형의 경우 침수초기 월류지점으로부터의 침수진행과정을 잘 모의할 수 있다. 그러나, 지형의 기복이 있는 유역에서 배수시스템을 통한 지표침수유량의 배수과정을 고려하지 못함으로 인하여, 월류발생이 끝난 후 일부지점이 계속 침수된 채 있게 된다. 이러한 연계모형의 한계로 인하여 두 모형의 통합모형이 필요하다. 즉, 강우 혹은 월류유량으로 발생한 지표유량 중 일부분이 과부하가 발생하지 않는 유입구 지점을 통과할 때 배수시스템으로 유입되는 것을 고려할 수 있고, 유입된 유량은 배수시스템 내의 흐름에 반영되도록 배수시스템과 침수해석모형을 통합한 모형 개발이 필요하다. 그러기 위해서는 지표면과 배수시스템에 대한 수리학적 관계를 정립하여야 한다. 본 연구에서는 배수시스템 해석 모형과 도시침수해석 모형을 통합하고, 두 모형간의 유량의 전송과정을 수리학적 관계를 고려한 dual-drainage 도시침수해석모형을 개발하였다. 이를 위해 도시지역 배수시스템 해석 모형으로 널리 이용되고 있는 SWMM모형을 이용하여 지표면으로의 월류량을 산정하고 유입된 지표유량에 대해서 배수시스템에서의 흐름해석을 수행하였다. 그리고, 침수해석을 위해서는 2차원 침수해석을 위한 DEM기반 침수해석모형을 개발하였고, 건물의 영향을 고려할 수 있도록 구성하였다. 본 연구결과 지표류 유출 해석의 물리적 특성을 잘 반영하며, 도시지역의 복잡한 배수시스템 해석모형과 지표범람 모형을 통합한 모형 개발로 인해 더욱 정교한 도시지역에서의 홍수 범람 해석을 실시할 수 있을 것으로 판단된다. 본 모형의 개발로 침수상황의 시간별 진행과정을 분석함으로써 도시홍수에 대한 침수위험 지점 파악 및 주민대피지도 구축 등에 활용될 수 있을 것으로 판단된다.

• The Korean Journal of Applied Statistics
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• v.25 no.2
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• pp.279-291
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• 2012

When fitting a Cox proportional hazards model with missing covariates, it is inefficient to exclude observations with missing values in the analysis. Furthermore, if the missing-data mechanism is not Missing Completely At Random(MCAR), it may lead to biased parameter estimation. Many approaches have been suggested to handle the Cox proportional hazards model when covariates are sometimes missing, but they are based on the selection model. This paper suggest an approach to handle Cox proportional hazards model with missing covariates by using the pattern-mixture model (Little, 1993). The pattern-mixture model is expressed by the joint distribution of survival time and the missing-data mechanism. In the pattern-mixture model, many models can be considered by setting up various restrictions, and different results under various restrictions indicate the sensitivity of the model due to missing covariates. A simulation study was conducted to show the sensitivity of parameter estimation under different restrictions in a pattern-mixture model. The proposed approach was also applied to mouse leukemia data.

• Journal of Korea Water Resources Association
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• v.43 no.3
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• pp.245-256
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• 2010

We study the basic theory and applicability of the WQUAL block in the FFC2Q model and the characteristics of non-point pollutant loads during the early stage of runoff. Study is also performed on selection of the values of the related parameters and their effect on the simulation results. FFC2Q simulation results are compared for verification with the measured data for three rainfall events in the Gunja Subbasin and found to be similar to the measured data in peak-flows, total runoff volumes, total loads, peak concentrations and times of peak concentration. This model thus shows results very close to those applying the SWMM and MOUSE models, even though it uses simplified input data. Related to rainfall distribution, under the condition of Huff 1st quartile distribution the pollutant loads occurred earlier than under other conditions, and in the early stage of rainfall the BOD and COD loads increased faster than the SS loads. The NPS loads were concentrated in the early stage of rainfall and finally reached total loads, so the rainfall after that could not contribute so much to the NPS loads.

• Korean Journal of Environment and Ecology
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• v.37 no.5
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• pp.337-346
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• 2023

Although wildlife bridge are built as a way to reduce habitat fragmentation caused by road construction, there is still a lot of debate about their effectiveness. Monitoring methods such as footprint traps and camera traps are used evaluate the effectiveness of wildlife bridge, but there is a limit to evaluate of effectiveness. In this study, the degree of use the wildlfe bridge was surveyed by striped field mouse that is likely use the wildlife bridge and surrounding as a habitat with capture-mark-recapture method.(Apodemus agraius). The distance and route of movement were identified by connecting the capture points, and the environmental factors on the use of the wildlife bridge implemented a generalized linear model(GLM) with the capture number of captured as a dependent variable. Consequently of capture, no individuals crossing the wildlife bridge, striped field mouse use the wildlife bridge as a habitat.The environmental factors affecting the use of mice were vegetation cover(1~2m, 2~8m, over 8m), vegetation construction, maximum diameter at breast height were positively correlated and slope was nagatively correlated. In conclusion, it is expected that the effectiveness of the wildlife bridge will be further improved by planting shrubs and trees and preventing high slope and cut slope increasing the utilization of the rat, such as being used as a food source in the ecosystem.