공사중단 방치건축물 정비 제도개선을 위한 실증연구: 충청남도를 중심으로

최정현,임준홍,Choi, Jeonghyeon,Im, Junhong 한국토지주택공사 토지주택연구원 2021 LHI journal of land, housing, and urban affairs Vol.12 No.1

우리나라는 경제성장과 위기, 사업성 부족 등 다양한 이유로 공사중단 방치건축물이 꾸준히 발생하고 있다. 공사중단 방치건축물은 다양한 형태와 규모로 분포하고 있으며 이로 인해 도시경관을 악화, 주거안정성을 저해하고, 화재 ·범죄·악취 등 다양한 도시문제를 야기하고 있다. 정부는 관련법을 제정·시행하고 있지만 시행과정에서 현실과 거리 있는 많은 문제점이 나타나고 있다. 이에, 본 연구는 충청남도 방치건축물을 대상으로 현지 실태조사, 건축관계인 및 이해관계인 심층인터뷰, 정비사업 시행자(LH), 도 및 시군 담당공무원 FGI를 통해 방치건축물 정비사업 추진의 문제점과 개선사항을 실증적으로 도출하였다. 그리고 이를 바탕으로 향후 방치건축물의 예방, 원활한 정비사업 추진을 위한 과제와 실효성 높은 제도개선사항을 제시하였다. South Korea is renowned as one of the countries which have experienced high economic growth in the past years. However since Global Financial Crisis in 2008, its economic growth has remained slow and majority cities have faced various issues in property sector such as declining property price, the increase of uncompleted building sites, abandoned land and disproportionate rate of vacant buildings. These abandoned sites in various scales and locations, particularly nearby residential areas have negative impacts on the urban environment such as crime and vandalism. To tackle these issue, in May 2013, the "Special Act on the Maintenance of Long-Term abandoned Buildings" was enacted and has been put into operation since May 2014. Subsequently, a base maintenance plan was established in 2016 by the Ministry of Land, Infrastructure and Transport. Nevertheless the plan has not been implemented properly due to the limitation of financial and human resources, lack of expertise and ambiguity of laws and guidelines. This study examines the challenges and barriers of the implementation of the Act and recommendations to resolve the urban issues are drawn. This study is a case study of Chungcheongnam-do and the main methods used are in-depth interviews and field surveys with a wide range of stakeholders including the main developer (LH), architects, surveyor and local authority officers. The findings suggest several improvement in the 'Special Act on the maintenance of long-term abandoned buildings'.

입자 필터를 이용한 월 물 수지 모형의 시간변화 매개변수 추정: 하천유량 자료의 동화

최정현,김상단,Choi, Jeonghyeon,Kim, Sangdan 한국수자원학회 2021 한국수자원학회논문집 Vol.54 No.6

Hydrological model parameters are essential for model simulation and can vary over time due to topography, climatic conditions, climate change and human activity. Consequently, the use of fixed parameters can lead to inaccurate stream flow simulations. The aim of this study is to investigate an appropriate method of estimating time-varying parameters using stream flow observations, and how the simulation efficiency changes when stream flow data are assimilated into the model. The data assimilation method can be used to automatically estimate the parameters of a hydrological model by adapting to a variety of changing environments. Stream flow observations were assimilated into a two parameter monthly water balance model using a particle filter. The simulation results using the time-varying parameters by the data assimilation method were compared with the simulation results using the fixed parameters by the SCEM method. First, we conducted synthesis experiments based on various scenarios to investigate if the particle filter method can adequately track parameters that change over time. After that, it was applied to actual watersheds and compared with the predictive performance of stream flow when using parameters that change with time and fixed parameters. The conclusions obtained through this study are as follows: (1) The predictive performance of the overall monthly stream flow time series was similar between the particle filter method and the SCEM method. (2) The monthly runoff prediction performance in the period except the rainy season was better in the simulation by the periodically changing parameters using the data assimilation method. (3) Uncertainty in the observational data of stream flow used for assimilation played an important role in the predictive performance of the particle filter.

습윤 지역의 기후-토양-식생-지하수위 상호작용을 반영한 개념적인 생태 수문 모형

최정현,김상단,Choi, Jeonghyeon,Kim, Sangdan 한국수자원학회 2021 한국수자원학회논문집 Vol.54 No.9

Vegetation processes have a significant impact on rainfall runoff processes through evapotranspiration control, but are rarely considered in the conceptual lumped hydrological model. This study evaluated the model performance of the Hapcheon Dam watershed by integrating the ecological module expressing the leaf area index data sensed remotely from the satellite into the hydrological partition module. The proposed eco-hydrological model has three main features to better represent the eco-hydrological process in humid regions. 1) The growth rate of vegetation is constrained by water shortage stress in the watershed. 2) The maximum growth of vegetation is limited by the energy of the watershed climate. 3) The interaction of vegetation and aquifers is reflected. The proposed model simultaneously simulates hydrologic components and vegetation dynamics of watershed scale. The following findings were found from the validation results using the model parameters estimated by the SCEM algorithm. 1) Estimating the parameters of the eco-hydrological model using the leaf area index and streamflow data can predict the streamflow with similar accuracy and robustness to the hydrological model without the ecological module. 2) Using the remotely sensed leaf area index without filtering as input data is not helpful in estimating streamflow. 3) The integrated eco-hydrological model can provide an excellent estimate of the seasonal variability of the leaf area index.

생태저류지 LID 시설의 강우유출수 처리비 산정

최정현,이옥정,김상단,Choi, Jeonghyeon,Lee, Okjeong,Kim, Sangdan 한국물환경학회 2017 한국물환경학회지 Vol.33 No.5

Because of the rapid progress of urbanization in recent decades, the proportion of impervious areas in cities has increased. As a result, hydrological properties of urban streams have changed and non-point pollution sources have increased, that have had considerable influence on human life and ecosystems. To manage these situations, application of non-point pollution reduction facilities and LID facilities are expanding recently. In this study, it is investigated if rainfall interception rate used in design of non-point pollution reduction facilities can be applied to design of LID facilities. For this purpose, EPA SWMM is constructed for part of Noksan National Industrial Complex area wherein long-term observed storm water data can be obtained and storm water interception rates for various design capacities of a bio-retention LID facility reservoirs are estimated. While sensitivity of storm water interception rate according to design specifications of bio-retention facility is not large, sensitivity of storm water interception rate according to regional rainfall characteristics is relatively large. As a result of comparing present rainfall interception rate estimation method with the one proposed in this study, the present method is highly likely to overestimate performance of the bio-retention facility. Finally, a new storm water interception rate formula for bio-retention LID facility is proposed.

도시유역의 물순환 및 수질 개선을 위한 저영향개발 시설의 비용 효율 분석

최정현 ( Jeonghyeon Choi ),김경민 ( Kyungmin Kim ),심인경 ( Inkyeong Sim ),이옥정 ( Okjeong Lee ),김상단 ( Sangdan Kim ) 한국물환경학회(구 한국수질보전학회) 2020 한국물환경학회지 Vol.36 No.3

As urbanization and impermeable areas have increased, stormwater and non-point pollutants entering the stream have increased. Additionally, in the case of the old town comprising a combined sewer pipe system, there is a problem of stream water pollution caused by the combined sewer overflow. To resolve this problem, many cities globally are pursuing an environmentally friendly low impact development strategy that can infiltrate, evaporate, and store rainwater. This study analyzed the expected effects and efficiency when the LID facility was installed as a measure to improve hydrologic cycle and water quality in the Oncheon stream in Busan. The EPA-SWMM, previously calibrated for hydrological and water quality parameters, was used, and standard parameters of the LID facilities supported by the EPA-SWMM were set. Benchmarking the green infrastructure plan in New York City, USA, has created various installation scenarios for the LID facilities in the Oncheon stream drainage area. The installation and maintenance cost of the LID facility for scenarios were estimated, and the effect of each LID facility was analyzed through a long-term EPA-SWMM simulation. Among the applied LID facilities, the infiltration trench showed the best effect, and the bio-retention cell and permeable pavement system followed. Conversely, in terms of cost-efficiency, the permeable pavement systems showed the best efficiency, followed by the infiltration trenches and bio-retention cells.

마코프 체인 몬테카를로 및 앙상블 칼만필터와 연계된 추계학적 단순 수문분할모형

최정현 ( Choi Jeonghyeon ),이옥정 ( Lee Okjeong ),원정은 ( Won Jeongeun ),김상단 ( Kim Sangdan ) 한국물환경학회(구 한국수질보전학회) 2020 한국물환경학회지 Vol.36 No.5

Hydrologic models can be classified into two types: those for understanding physical processes and those for predicting hydrologic quantities. This study deals with how to use the model to predict today's stream flow based on the system's knowledge of yesterday's state and the model parameters. In this regard, for the model to generate accurate predictions, the uncertainty of the parameters and appropriate estimates of the state variables are required. In this study, a relatively simple hydrologic partitioning model is proposed that can explicitly implement the hydrologic partitioning process, and the posterior distribution of the parameters of the proposed model is estimated using the Markov chain Monte Carlo approach. Further, the application method of the ensemble Kalman filter is proposed for updating the normalized soil moisture, which is the state variable of the model, by linking the information on the posterior distribution of the parameters and by assimilating the observed steam flow data. The stochastically and recursively estimated stream flows using the data assimilation technique revealed better representation of the observed data than the stream flows predicted using the deterministic model. Therefore, the ensemble Kalman filter in conjunction with the Markov chain Monte Carlo approach could be a reliable and effective method for forecasting daily stream flow, and it could also be a suitable method for routinely updating and monitoring the watershedaveraged soil moisture.

지역 파급효과를 중심으로 한 공사중단 방치건축물 정비사업 우선순위 선정방식에 대한 연구

최정현 ( Jeonghyeon Choi ),우명제 ( Myungje Woo ) 전남대학교 지역개발연구소 2021 지역개발연구 Vol.53 No.3

우리나라는 급속한 경제발전 시기를 지나 이미 저성장형 경제구조로 고착화 되어가고 있으며, 저출산 고령화, 외연적 개발확산 등의 사회적·공간적 문제가 중첩되어 도시 내부에서는 빈집, 빈점포 등 유휴방치부동산이 도시문제로 대두되기 시작하였다. 특히 공사 진행 중에 부도, 파산, 권리관계 등으로 인해 건설공사를 중단한 공사현장은 도시미관 악화, 범죄발생, 재난재해 등 다양한 문제를 내포하고 있다. 이런 문제에 대응하기 위하여 지난 2013년 5월 「공사중단 장기방치 건축물의 정비 등에 관한 특별조치법」이 제정되었다. 특별법에 따라 광역자치단체별로 방치건축물 정비계획을 수립하여 정비사업을 추진하도록 하고 있으며, 정비사업 우선순위를 선정하기 위한 평가항목으로 “시급성, 파급효과”, “사업성”, “시군구 추진의지”, “이해관계인 추진의지”, “사업추진 용이성” 등 5개 분야를 제시하고 있으나, “시급성, 파급효과” 분야는 평가할 수 있는 적절한 분석방법이 부재하여 단순히 전문가의 현장답사 및 서류심사로 판단하고 있는 실정이다. 이에 본 연구는 제한된 공공재원을 활용하여 추진하는 공공사업임을 감안하여 “시급성, 파급효과”를 판단하는 항목에 공간 위계를 고려한 위세 중심성, 지역 쇠퇴도 등을 종합하여 정비사업 우선순위를 결정하는 방식을 제안한다. Korea has passed a period of rapid economic development and has already been fixed into a low-growth economic structure, and social and spatial problems, such as low fertility, aging, and expansion of development, are overlapping. In particular, construction sites that have stopped construction works due to bankruptcy, and rights relations in the middle of construction have various problems such as deterioration of urban aesthetics, crimes, and disasters. In accordance with the the 「Act on Special Measures for the Maintenance of Buildings that Have been Abandoned for a Long Time」, enacted to combat these issues, each metropolitan government establishes a maintenance plan for abandoned buildings and promotes maintenance projects. Five areas are suggested as evaluation items to select the priority of the maintenance projects. Among them, since the field of “urgency and ripple effect” does not have an appropriate analysis method that can be evaluated, it has simply been judged by expert on-site visits and document reviews. Therefore, this study intends to propose a method for determining the priority of the maintenance projects by combining the items that judge “urgency and ripple effect” with the centrality of prestige and the degree of regional decline considering the hierarchy of space.

WRF Model의 초기 및 경계조건 개선이 태풍 강우량 모의에 미치는 영향

최정현(Choi Jeonghyeon),이정훈(Lee Jeonghoon),정현교(Jeong Hyeon gyo),장주형(Jang Juhyoung),김상단(Kim Sangdan) 한국방재학회 2018 한국방재학회논문집 Vol.18 No.2

본 연구에서는 Weather Research and Forecast(WRF) 모델의 초기조건 및 경계조건의 개선이 태풍에 의한 강우량 모의에 미치는 영향을 분석하였다. 이를 위하여 태풍 매미를 대상으로 WRF 모델을 구축하고, 다양한 방법으로 초기조건 및 경계조건을 개선한 후 각각의 개선방법별로 모의된 결과를 비교하였다. 태풍 경로의 재현에 가장 큰 영향을 주는 개선방법은 태풍초기화기법의 적용으로 나타났다. 누적강우량의 재현의 경우 태풍초기화기법을 적용하였을 때 강우의 공간적인 분포 형태에 영향을 미쳤다. 또한, 다양한 경계조건 중에서 상대습도의 조정이 누적강우량에 가장 큰 영향을 미치고 있었으며, 전 지구자료에 덧붙여서 지역 관측 자료를 포함하여 WRF 모델을 구축하는 것이 지역적인 강우량 분포패턴의 재현에 유의하게 도움을 주는 것으로 나타났다. 또한 모든 개선방법을 적용할 경우, 태풍 매미의 공간평균 시간강우량이 더 잘 재현되는 것을 살펴볼 수 있었다. In this study, it is analyzed that the influence of the improvement of the initial and boundary conditions in Weather Research and Forecast (WRF) model on reproducing typhoon rainfall. After WRF model for typhoon MAEMI is constructed and its initial and boundary conditions are improved by various methods, the results of the typhoon rainfall simulation by each improvement method are compared. The application of the typhoon initialization technique had the greatest effect on the reproduction of the typhoon path. In the sense of the accumulated rainfall depth, the application of the typhoon initialization technique had a lot of influence on the spacial distribution. In addition, the adjustment of the relative humidity among various boundary conditions had the greatest effect on the cumulative rainfall depth, and building a WRF model including the regional data in addition to the global data significantly contributed to the reproduction of the local rainfall field. When all the improvement methods were applied, it could be said that the spatially averaged hourly rainfall pattern of the typhoon MAEMI was better reproduced.

스마트 어류 양식을 위한 딥러닝 기반 실시간 어류 객체 검출 연구

최정현(Jeonghyeon Choi),최한석(Han Suk Choi),신영학(Younghak Shin) 대한전자공학회 2020 대한전자공학회 학술대회 Vol.2020 No.8

Domestic aquaculture fisheries production continues to grow. However, the process of aquaculture fisheries still depends on human experience. Recently, with the development of IT technology, the automation technology of aquaculture has been studied. In this study, a real-time fish object detection method based on deep learning as a basic step required for smart farming was studied, and performance was evaluated and verified using actual fish data.

해수면온도가 태풍강우 최대화에 미치는 영향

최정현(Choi Jeonghyeon),이옥정(Lee Okjeong),장수형(Jang Suhyung),조덕준(Jo Deok Jun),김상단(Kim Sangdan) 한국방재학회 2018 한국방재학회논문집 Vol.18 No.6

본 연구에서는 태풍 매미를 대상으로 WRF (Weather Research and Forecast) 모형을 이용하여 초기 및 경계조건의 해수면온도 및 상대습도의 변경을 통해 태풍 강우량을 최대화하고, 해수면온도가 태풍 강우량의 최대화에 미치는 영향을 분석하고자 하였다. 사전연구를 통해 수치적으로 재현된 태풍 매미를 기반으로, 태풍으로 유입되는 수증기량을 증가시켜 태풍강우를 최대화하고자 하였다. 이를 위하여 모형의 초기 및 경계조건 중 상대습도를 100 %로 고정하고 해수면온도를 0.0 ℃에서 5.0 ℃까지 증가시켜가며 태풍 강수량이 모의되었다. 모의된 태풍의 강우를 살펴본 결과, 해수면온도의 증가에 따라 모의된 총 강우량의 공간적인 분포가 매우 다양하게 나타났으며, 특히 해수면온도의 변화는 육지에 떨어지는 강우량에 많은 영향을 미치는 것을 살펴볼 수 있었다. 또한, 해수면온도의 증가와 육지에 떨어지는 강우량은 선형적인 관계를 나타내지 않는 것으로 나타났다. 따라서 태풍강우 최대화를 위해서는 무조건적으로 해수면온도를 증가시켜 WRF를 구동하기 보다는 다양한 조건에 대한 수치실험을 반복하여 모의하고자 하는 태풍에 가장 적합한 최적 해수면온도 증가량을 탐색할 필요가 있을 것으로 판단된다. In this study, the WRF (Weather Research and Forecast) model was used to maximize typhoon rainfall depth by changing the sea surface temperature (SST) and relative humidity in the initial and boundary conditions. The effects of SST on maximizing typhoon rainfall depth were analyzed. Typhoon MAEMI’s rainfall depth, which was numerically reproduced by pre-study, was maximized by increasing the amount of water vapor entering the typhoon. For this, the relative humidity of the initial and boundary conditions of the model was fixed at 100 %, and the typhoon rainfall was simulated by increasing SST from 0.0 °C to 5.0 °C. The simulation of typhoon rainfall under various SSTs indicates that the spatial distribution of the simulated total rainfall depth varies with increasing SST. In particular, it can be seen that the change in SST greatly affects the rain falling on the land. In addition, it is found that the total rainfall depth on land and changes in SST do not exhibit a linear relationship. Therefore, it is necessary to investigate the optimal increase in SST in accordance with the target typhoon by carrying out repeated numerical experiments using various SST conditions, rather than unconditionally increasing SST to maximizing typhoon rainfall depth.