• Journal of Korean Society on Water Environment
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• v.39 no.3
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• pp.231-239
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• 2023

Public sewage treatment facilities are a necessary infrastructure for public health that treat sewage generated in cities and basin living areas and discharge it into rivers or seas. Recently, the role of public sewage treatment is receiving attention as a place of use of wastewater-based epidemiology (WBE), which analyzes human specific metabolic emissions or biomarkers present in sewage to investigate the environment to which the population is exposed in the water drain. WBE is mainly applied to investigate legal and water-law drug use or to predict and analyze the lifestyle of local residents. WBE has also been applied to predict and analyze the degree of infectious diseases that are prevalent worldwide, such as COVID-19. Since sewage flowing into public sewage treatment facilities includes living information of the population living in the drainage area, it is easy to collect basic data to predict the confirmation and spread of infectious diseases. Therefore, it is necessary to establish a new role of public sewage treatment facilities as an infrastructure necessary for WBE that can obtain information on the confirmation and spread of infectious diseases other than the traditional role of public sewage treatment. In South Korea, the sewerage supply rate is about 95.5% and the number of public sewage treatment facility is 4,209. This means that the infrastructure of sewerage is fully established. However, to successfully drive for WBE , research on monitoring and big-data analysis is needed.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.43 no.5
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• pp.601-610
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• 2023

The comprehension of water-level behavior in rivers is essential for effective flood and river environmental management. The objective of this study is to propose a methodology that can be used by field engineers engaged in actual practice, to readily identify the characteristics of water-level behavior during flood events. To this end, a total of 45 historical water-level records from 2010 to 2022 year, which provide flood information for the flood vulnerable districts of the Han River, were obtained. A Water-level Rise Behavior Curve (WRBC) was developed and suggested to quantify the amount of water-level rise per unit time during flood. As a result, the water-level rises by more than 80% of the total rise within the first 6.2 hours, followed by a gradual rise. The time required to achieve a particular equilibrium varied depending on the area and runoff characteristics of the upstream. Furthermore, the study revealed that the WRBC provides a statistical representation of the water-level rise trend during floods, and can be effectively utilized for flood mitigation measures in waterfront spaces and irrigation facilities.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.5B
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• pp.489-499
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• 2006

The Potential Flood Damage (PFD) is widely used for representing the degree of potential of flood damage. However, this cannot be related with the design frequency of river basin and so we have difficulty in the use of water resources field. Therefore, in this study, the concept of Potential Risk for Flood Damage Occurrence (PRFD) was introduced and estimated, which can be related to the design frequency. The PRFD has three important elements of hazard, exposure, and vulnerability. The hazard means a probability of occurrence of flood event, the exposure represents the degree that the property is exposed in the flood hazard, and the vulnerability represents the degree of weakness of the measures for flood prevention. Those elements were devided into some sub-elements. The hazard is explained by the frequency based rainfall, the exposure has two sub-elements which are population density and official land price, and the vulnerability has two sub-elements which are undevelopedness index and ability of flood defence. Each sub-elements are estimated and the estimated values are rearranged in the range of 0 to 100. The Analytic Hierarchy Process (AHP) is also applied to determine weighting coefficients in the equation of PRFD. The PRFD for the Anyang river basin and the design frequency are estimated by using the maximum rainfall. The existing design frequency for Anyang river basin is in the range of 50 to 200. And the design frequency estimation result of PRFD of this study is in the range of 110 to 130. Therefore, the developed method for the estimation of PRFD and the design frequency for the administrative districts are used and the method for the watershed and the river channel are to be applied in the future study.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.1B
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• pp.79-88
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• 2006

In this study, a methodology is developed for flood runoff analysis considering the interaction between interior floodplain and channel. Riparian lowland is modeled as storage areas by HEC-RAS and is connected with main channel through gravity drainage structure and pumping stations. As a result, we were able to compute the difference between runoff into the interior floodplain and delayed runoff to main channel from interior floodplain. This allowed us to compute the storage change in the interior floodplain and corresponding inundation areas. Furthermore, the levee is modeled as a lateral structure and the flood from the main channel to interior floodplain is modeled by installing a weir on top of it. In addition, levee breach is also modeled so that flooding from main channel to interior floodplain can be considered. Computed flooding depth in the storage areas are compared with elevation to identify the inundated areas and flood maps can then be produced for a desired time or for the extent of flooding given a flooding depth. Output from this modeling effort can provide many useful information for flood planning such as flow depth in main channel, flooding depth and area in interior floodplain. The method was applied to Sapgyo river basin and the comparison with observed flood events showed that it can reproduce the observation fairly well, hence proving the utility of the method.

• Journal of the Korean earth science society
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• v.45 no.1
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• pp.72-84
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• 2024

Recently, the vulnerability of water resources has been increasing owing to climate change, highlighting the importance of groundwater. In particular, the Nakdong River Basin, located in the southern part of Korea, experiences frequent water scarcity phenomena, such as droughts. This study analyzed the hydrogeological characteristics of the study area by examining groundwater and stream water in the Gwangrye Stream, downstream of the Nakdong River Basin, in August and October 2023. Therefore, we collected samples from 54 groundwater wells and five streams for water quality analysis. The results of the field tests indicated an increasing trend in electrical conductivity from upstream to downstream in the study area. Laboratory analyses confirmed that the concentration of Na increased from upstream to downstream more than that of Ca. In conclusion, both stream water and groundwater were influenced by anthropogenic contamination. These changes were closely related to land use in the study area. The upstream areas are primarily composed of forests, whereas the downstream areas are composed of industrial complexes, wastewater treatment facilities, and agricultural areas, which are likely to affect both stream water and groundwater.

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.6
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• pp.149-153
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• 2008

The pollutant capacity occurred before and after the development of a watershed should be quantitatively estimated and controlled for the minimization of water contamination. The Ministry of Environment suggested a guideline for the legal management of nonpoint source from 2006. However, the rational method for the determination of treatment capacity from nonpoint source proposed in the guideline has the problem in the field application because it does not reflect the project based cases and overestimates the pollutant load to be reduced. So, we perform the standard rainfall analysis by analytical probabilistic method for the estimation of an additional pollutant load occurred by a project and suggest a methodology for the estimation of contaminant capacity instead of a simple rational method. The suggested methodology in this study could determine the reasonable capacity and efficiency of a treatment facility through the estimation of pollutant load from nonpoint source and from this we can manage the watershed appropriately. We applied a suggested methodology to the projects of housing land development and a dam construction in the watersheds. When we determine the treatment capacity by a rational method without consideration of the types of projects we should treat the 90% of pollutant capacity occurred by the development and to do so, about 30% of the total cost for the development should be invested for the treatment facility. This requires too big cost and is not realistic. If we use the suggested method the target pollutant capacity to be reduced will be 10 to 30% of the capacity occurred by the development and about 5 to 10% of the total cost can be used. The control of nonpoint source must be performed for the water resources management. However it is not possible to treat the 90% of pollutant load occurred by the development. The proper pollutant capacity from nonpoint source should be estimated and controlled based on various project types and in reality, this is very important for the watershed management. Therefore the results of this study might be more reasonable than the rational method proposed in the Ministry of Environment.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.530-534
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• 2006

조류발전은 조류 유속이 빠른 곳에 수차발전기를 설치하여 해수의 운동에너지로부터 전기를 생산하는 발전방식이다. 2001년부터 해양연구원에서는 울돌목의 우수한 조류발전 개발 여건을 바탕으로 조류에너지 실용화 기술을 개발하고 있다. 본 연구에서는 조류발전 시스템에 사용되는 헬리컬 수차의 효율을 현장실험을 바탕으로 판단하고자 하였다. 현장실험을 위하여 지름 2.2 m, 높이 2.5 m의 수차를 제작하고, 울돌목 협수로의 한 쪽 면에 쟈켓구조물을 설치하여 수차를 거치한다. 수차가 회전함에 따라 회전봉에 일정 마찰을 주어 토크와 RPM을 측정하고, 함께 측정된 유속자료를 이용하여 수차를 효율을 산정한다. 유속-수차효율, TSR(수차의 날개속도와 유속의 비)-수차효율의 상관관계로 실험결과를 고찰하였다. 1중 날개 수차인 경우에 유속 1.4에서 2.6 m/s 사이에서 최대효율이 30 - 35 % 정도였고, 2중 날개 수차에 대한 실험에서는 유속 1.4에서 2.6 m/s 사이에서 최대수차효율이 25 - 35 % 사이임을 알 수 있었다. TSR과 최대수차효율의 상관관계는 실험 case별로 조금씩 다르다. 전체적으로 1중 날개의 경우가 최대수차효율에서 2중 날개보다 TSR 값이 조금 큰 경향을 나타냄을 알 수 있다. 이것은 1중 날개가 2중 날개보다 가벼워 좀 더 큰 RPM을 발생시켜서 나타난 현상으로 생각된다. 현재의 실험결과들을 이용하여 TSR과 최대수차효율을 상관관계를 나타내는 모델식을 도출하였다. 현장시험결과를 종합하면, 현장조류발전 시설이 최소 600 kW의 전력이 생산되기 위해서는 지름 3 m, 높이 3.6 m 인 수차 3개가 하나의 축에 설치되어야하는 것으로 계산되었다. 정격유속이 4.8 m/s이고 수차의 지름이 3m 라면, 최적 전력발생시의 RPM은 1중 날개의 경우 79이고 2중 날개의 경우는 63정도임을 추정할 수 있었다.촬영하여 실시간으로 전송하기 때문에 홍수시 하천 상황에 대한 모니터링 목적으로 사용될 수 있다. 영상수위계는 우물통 등을 이용하는 기존 방법과 비교하여 구조물이 필요 없어 설치 비용이 저렴하고, 영상에 의한 하천 모니터링 기능을 자체적으로 가지고 있기 때문에 효율적이라고 할 수 있다.따른 4개의 평가기준과 26개의 평가속성으로 이루어진 2단계 기술가치평가 모형을 구축하였으며 2개의 개별기술에 대한 시범적용을 실행하였다.하는 것으로 추정되었다.면으로의 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. 있을 것으로 판단되었다.4일간의 기상변화가 자발성 기흉 발생에 영향을 미친다고 추론할 수 있었다. 향후 본 연구에서 추론된 기상변화와 기흉 발생과의 인과관계를 확인하고 좀 더 구체화하기 위한 연구가 필요할 것이다.게 이루어질 수 있을 것으로 기대된다.는 초과수익률이 상승하지만, 이후로는 감소하므로, 반전거래전략을 활용하는 경우 주식투자기간은 24개월이하의 중단기가 적합함을 발견하였다. 이상의 행태적 측면과 투자성과측면의 실증결과를 통하여 한국주식시장에 있어서 시장수익률을 평균적으로 초과할 수 있는 거래전략은 존재하므로 이러한 전략을 개발 및 활용할 수 있으며, 특히, 한국주식시장에 적합한 거래전략은 반전거래전

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.1241-1245
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• 2006

절 성토사면에 구조물을 설치할 경우 가장 중요하게 고려되어야 하는 점은 사면의 안정성 여부이다. 특히, 절 성토사면에 설치된 구조물이 붕괴되는 가장 큰 원인은 뒷채움재 내에 존재하는 수압의 영향이라는 것을 우리는 이미 많은 연구와 경험을 통해 알고 있다. 만일 지하수위가 존재하는 상태에서 단시간에 발생되는 집중호우로 인해 수위가 갑자기 상승하였을 경우, 구조물을 통해 전혀 배수되지 않는다면 절 성토사면의 안정성은 급격히 저하될 것이다. 이러한 사면의 배수압을 소산시킬 수 있는 공법은 여러 가지가 있으나, 본 연구에서는 특히 제주도의 지역적 특성을 고려하여 화산석을 채움재로 사용한 Mattress/Filter를 절 성토사면에 설치함으로써 배수압을 소산시킬 수 있는 방법을 연구하였다. Mattress/Filter는 제방 또는 절 성토사면의 파괴와 침식을 방지하기 위해 사면에 설치하는 육각형의 철망구조로서 유연성, 다공성, 배수성 및 식생성과 같은 특징이 있으며, 콘크리트 구조물과 달리 별도의 배수시설을 필요로 하지 않는 장점이 있다. 또한 본 연구에 사용된 Mattress/Filter의 채움재인 화산석은 현재 제주도 지역에 방대하게 분포되어 있다. 특히 현무암은 제주도 암석 전체의 90%이상을 차지하고 있으며, 투수성이 매우 큰 암석이다. 현무암의 공극률은 그 종류에 따라 $0.02{\sim}0.36$의 범위로 나타난다. 특히, 표선리현무암의 경우 평균 공극률이 0.23으로 나타나 모래의 공극률인 $0.3{\sim}0.8$에 비교하여 볼 때, 연구에 사용된 재료는 아주 우수한 투수성을 가진 것으로 판명된다. 또한 현무암의 경우 암석의 겉 표면이 미세한 다공질 조직으로 이루어져 있다. 따라서 암석자체에 물이 정체될 수 있어 구조물을 통해 배수될 때 암석이 머금고 있는 물로 인해 추가적으로 발생하는 중력은 다른 재료가 가지지 못한 화산석의 또 다른 장점이라 할 수 있다.서는 자료변환 및 가공이 필요하다. 즉, 각 상습침수지구에 필요한 지형도는 국립지리원에서 제작된 1:5,000 수치지형도가 있으나 이는 자료가 방대하고 상습침수지구에 필요하지 않은 자료들을 많이 포함하고 있으므로 상습침수지구의 데이터를 인터넷을 통해 서비스하기 위해서는 많은 불필요한 레이어의 삭제, 서비스 속도를 고려한 데이터의 일반화작업, 지도의 축소.확대 등 자료제공 방식에 따른 작업 그리고 가시성을 고려한 심볼 및 색채 디자인 등의 작업이 수반되어야 하며, 이들을 고려한 인터넷용 GIS기본도를 신규 제작한다. 상습침수지구와 관련된 각종 GIS데이타와 각 기관이 보유하고 있는 공공정보 가운데 공간정보와 연계되어야 하는 자료를 인터넷 GIS를 이용하여 효율적으로 관리하기 위해서는 단계별 구축전략이 필요하다. 따라서 본 논문에서는 인터넷 GIS를 이용하여 상습침수구역관련 정보를 검색, 처리 및 분석할 수 있는 상습침수 구역 종합정보화 시스템을 구축토록 하였다.N, 항목에서 보 상류가 높게 나타났으나, 철거되지 않은 검전보나 안양대교보에 비해 그 차이가 크지 않은 것으로 나타났다.의 기상변화가 자발성 기흉 발생에 영향을 미친다고 추론할 수 있었다. 향후 본 연구에서 추론된 기상변화와 기흉 발생과의 인과관계를 확인하고 좀 더 구체화하기 위한 연구가 필요할 것이다.게 이루어질 수 있을 것으로 기대된다.는 초과수익률이 상승하지만, 이후로는 감소하므로, 반전거래전략을 활용하는 경우 주식투자기간은 24개월이하의 중단기가 적합함을 발견하였다. 이상의 행태적 측면과 투자성과측면의 실증결과를 통하여 한국주식시장에 있어서 시장수익률을 평균적으로 초과할 수 있는 거래전략은 존재하므로 이러한 전략을 개발 및 활용할 수 있으며, 특히, 한국주식시장에 적합한 거래전략은 반전거래전략이고, 이 전략의 유용성은 투자자가 설정한 투자기간보다 더욱 긴 분석기간의 주식가격정보에 의하여 최대한 발휘될 수 있음을 확인하였다.(M1), 무역적자의 폭, 산업

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.869-877
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• 2008

The purpose of this study is to investigate the trends and patterns of variou kind of water uses in a household by metering in Korea. Water use components are classified by toilet, washbowl, bathing, laundry, kitchen, etc. Flow meters are installed in 146 household selected by sampling in all around Korea. The data are gathered by web-based data collection system from the year 2002 to 2006, considering pre-investigated data such as occupation, revenue, family members, housing types, age, floor area, water saving devices, education, etc. Reliable data are selected by upper fence method for each observed water use component and statistical characteristics are estimated for each residential type to determine liter per capita per day. Estimated domestic per capita day show an indoor water use with the range from $150{\ell}pcd$ to $169{\ell}pcd$ for each housing type as the order of high rise apartment, multi-house, and single house. As the order of consuming amount among water use components, it is investigated that toilet($38.5{\ell}pcd$) is the first, and the second is laundry water($30.8{\ell}pcd$), the third is kitchen($28.4{\ell}pcd$), the fourth is bathtub($24.7{\ell}pcd$), the next is washbowl($15.4{\ell}pcd$). The results are compared with water uses in U.K. and U.S. As life style has been changed into western style, pattern of water use in Korea is tend to be similar with the U.S. water use pattern. Compared with the surveying results by Bradley, on 1985. Thirty liter of total use increased with the advancement of economic level, and a little change of water use pattern can be found. Especially, toilet water take almost half part of total water use and laundry water shows lowest as 11% in surveying at the year of 1985. But, this study shows that 39 liter, 28% of toilet water, has been decreased by the spread of saving devices and campaign. It is supposed that the spread large sized laundry machine make by-hand laundry has been decreased and water use increased. Unit water amount of each end-use in household can be applied to design factor for water and wastewater facilities, and it play a role as information in establishing water demand forecasting and conservation policy.

• Journal of the Korean Geographical Society
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• v.48 no.1
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• pp.87-111
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• 2013

Regional disparities between eastern and western regions is the most of serious problem for balanced regional development in Turkey. The Southeastern Anatolia Project (GAP) is being implemented to eliminate these regional development disparities. The work that was initially planned as predominantly for hydraulic energy production to utilize water resources of the Tigris and Euphrates rivers more effectively was later transformed into an integrated multi-sector regional development project. This study noted that this region had very limited cash crop production because of the constraints of semi-arid climate of the southeastern region, however, later, it has changed Turkey's major cotton producing region since Southeastern Anatolia Project carried out. Therefore, this study investigated background, process, and content of the Southeastern Anatolia Project with respect to high cotton productivity in this region and examined the dynamic changes of cotton productivity in this region. In addition, Sanliurfa prefecture is one of the main development axes of the Southeastern Anatolia Project, because government investments are concentrated on this prefecture. Therefore, this study examined the background and process of cotton farming growth in this prefecture. In 2011, Sanliurfa prefecture produced 37.6% of Turkey's total cotton production. This is mainly due to agricultural infrastructure expansion such as land consolidation, irrigation, roads and farm roads. Also, it is one of the main factor that subsidies paid to farmers for cotton cultivation. The introduction of irrigation has dramatically changed the direction of seasonal migration of this area. Prior to irrigation, this area had a serious social issue about out-migration for seasonal labor to other areas. However, the introduction of irrigation made this area that changed to in-migration and intramigration for cotton cultivation. Irrigation water is supplied to farmers through the WUAs (Water User Associations) that handed over irrigation water management, operation from DSI (General Directorate of State of Hydraulic Works). However, the WUAs are under the influence of Ashiret, a traditional feudal social structure. Because of this reason, it does not have an efficient management for farmers. Also, it is one of the reasons that this area does not have autonomous farmer organization.