• Korean Journal of Agricultural Science
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• v.32 no.2
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• pp.107-126
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• 2005

The most limited production resource in Korea is land. During the period from 1995 to 2002, annual farm land area of 17,600ha have been converted to urban and industrial land. The self-sufficiency rate of rice, Korean staple food, is expected to be decreased from 97.5% in 2003 to 60-70% in 2020. Under such conditions, this study is aimed at first identifying multi-functional benefits of the reclamation projects such as agricultural production, industrial water supply, urban land supply, transportation effects, sightseeing effects and environmental values with and without the projects. To carry out the objectives, three existing tideland reclamation projects such as Daeho, Kumgang and Yongsangang irrigation project stage II were evaluated and Saemangeum tideland reclamation project which was jointly revaluated by environmental NGO and Govn't appointed specialists in 2000 was reviewed. According to this study results, tide land reclamation projects were showed financially and economically feasible and environmentally sustainable. The joint cost like estuary dam should be allocated based on the multi-functional benefits of the projects. To allocate the joint cost, legal and institutional improvement should adapt the joint cost allocation method as the specific cost-remaining benefit method. Korea has more than 402,000 ha of tidal flat of which 76,396ha have been reclaimed in 2003. To meet food security and to cope with shortage of land, phil-environmental reclamation projects should be continuously implemented and necessary tidal flats for protecting environmental ecosystem should be remained according to the detail survey results of reclaimable resources.

• Magazine of the Korean Society of Agricultural Engineers
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• v.26 no.2
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• pp.106-124
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• 1984

Monthly streanflow of watersheds is one of the most important elements for the planning, design, and management of water resources development projects, e.g., determination of storage requirement of reservoirs and control of release-water in lowflow rivers. Modeling of longterm runoff is theoretically based on water-balance analysis for a certain time interval. The effect of the casual factors of rainfall, evaporation, and soil-moisture storage on streamflow might be explained by multiple regression analysis. Using the basic concepts of water-balance and regression analysis, it was possible to develop a generalized model called the Regionalized Regression Model for Monthly Streamflow in Korean Watersheds. Based on model verification, it is felt that the model can be reliably applied to any proposed station in Korean watersheds to estimate monthly streamflow for the planning, design, and management of water resources development projects, especially those involving irrigation. Modeling processes and properties are summarized as follows; 1. From a simplified equation of water-balance on a watershed a regression model for monthly streamflow using the variables of rainfall, pan evaporation, and previous-month streamflow was formulated. 2. The hydrologic response of a watershed was represented lumpedly, qualitatively, and deductively using the regression coefficients of the water-balance regression model. 3. Regionalization was carried out to classify 33 watersheds on the basis of similarity through cluster analysis and resulted in 4 regional groups. 4. Prediction equations for the regional coefficients were derived from the stepwise regression analysis of watershed characteristics. It was also possible to explain geographic influences on streamflow through those prediction equations. 5. A model requiring the simple input of the data for rainfall, pan evaporation, and geographic factors was developed to estimate monthly streamflow at ungaged stations. The results of evaluating the performance of the model generally satisfactory.

• Journal of Korean Tunnelling and Underground Space Association
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• v.17 no.5
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• pp.563-573
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• 2015

For hard rock subsea tunnels the most challenging rock mass conditions are in most cases represented by major faults/weakness zones. Poor stability weakness zones with large water inflow can be particularly problematic. At the pre-construction investigation stage, geological and engineering geological mapping, refraction seismic investigation and core drilling are the most important methods for identifying potentially adverse rock mass conditions. During excavation, continuous engineering geological mapping and probe drilling ahead of the face are carried out, and for the most recent Norwegian subsea tunnel projects, MWD (Measurement While Drilling) has also been used. During excavation, grouting ahead of the tunnel face is carried out whenever required according to the results from probe drilling. Sealing of water inflow by pre-grouting is particularly important before tunnelling into a section of poor rock mass quality. When excavating through weakness zones, a special methodology is normally applied, including spiling bolts, short blast round lengths and installation of reinforced sprayed concrete arches close to the face. The basic aspects of investigation, support and tunnelling for major weakness zones are discussed in this paper and illustrated by cases representing two very challenging projects which were recently completed (Atlantic Ocean tunnel and T-connection), one which is under construction (Ryfast) and one which is planned to be built in the near future (Rogfast).

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.1545-1549
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• 2008

최근 이상홍수나 가뭄과 같은 물 관련 재해의 발생빈도가 높아지고, 산업 고도화, 인구증가와 같은 원인에 의해 장 단기적 물 부족 현상이 우려되면서 수자원 사업에 대한 관심이 고조되고 있다. 대부분의 수자원 사업은 공공성이 매우 크기 때문에 대규모 정부예산의 투입을 필요로 하고 있으나, 수자원사업의 특성상 사업의 공공성에 반하여 사업 시행에 따른 여러 경제적, 정책적 이해관계가 난립하여 사업 시행에 어려움이 따르고 있는 것이 실정이다. 이에 따라 '수자원(댐)부문사업의 예비타당성조사 표준지침 연구-제3판'에서는 수자원 사업의 타당성 평가를 위해 크게 경제성분석과 정책적분석의 두 부문으로 접근하고 있으며, 최종적으로 다기준의사결정기법 중 하나인 AHP기법을 이용하여 결정함으로써 수자원 사업의 가치 평가에 대한 이해를 돕고 있다. 본 연구에서는 지난 1999년부터 2006년까지 수행된 수자원분야 및 타분야의 사례를 바탕으로 수자원사업 예비타당성조사의 실태를 파악함으로써 현재 지적되고 있는 문제점을 고찰하고 그에 따른 해결방향을 제시하고자 하였다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.2
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• pp.542-550
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• 2020

A stream serve the functions of different water utilization, flood control, and the environment, and contributes to the development of national life and culture. On the other hand, it is difficult to efficiently evaluate various projects, such as effectiveness verification and comparison between projects, because the evaluation procedures and evaluation techniques of projects are not uniform and different for each institution. Therefore, a standardization technology was developed for a post-assessment of stream projects that can recognize stream problems and comprehensively evaluate stream-related projects. To this end, various projects, such as project evaluation techniques, national R&D projects, and social welfare projects, were compared and analyzed, and the standardization stages of the project were first suggested. In addition, based on the standardization stage, the evaluation indices for each stage were derived to develop an evaluation table that can evaluate stream-related projects comprehensively. Finally, it is possible to prevent the repeated use of failure factors in the planned projects.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.6
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• pp.726-734
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• 2018

The total number of Sea Area Utilization Consultation in the environment management sea areas reviewed from 2015 to 2017 were 60. The number of development projects in the environment conservation sea areas decreased steadily, but special management sea areas increased. Development types in environment management sea areas showed that artificial structure installation was the highest ratio, followed by fishery port development and construction of habor and coastal maintenance and sea water intake and draining. By comparing the trend of water quality changes using marine environment information system (MEIS) data in the environment management areas from 2006 to 2017, COD showed no significant changes but the environment conservation sea areas increased slightly, and the concentration of TN and TP decreased. Gwangyang and Masan bays in the special management sea areas and Gamak bay in the environment conservation sea areas displayed oxygen deficient mass in the summer. As the use of development projects of the environment management sea areas are performed continuously, an analysis of the status of sufficient water quality changes is necessary for environmental impact assessment (Sea Area Utilization Consultation) in the marine environment and should be evaluated mainly for management of contamination by diagnosing thoroughly water quality effects and the pollution of sediment. Especially, the water quality goal for the purpose of designation in each of the environment management sea areas is set clearly, connection with pollution source control and the total pollution load management system (TPLMS) should be proposed and measured to reduce the amount of contaminated water.

• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.191-191
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• 2016

Hai River Basin is one of China's major agricultural areas, with a huge rural population. Water conservancy is of great importance in this region. There are three integral elements in managing rural water resources: the consideration of current situation, the adoption of effective management measures, and the projection of future needs. In this study, we provide an in-depth investigation of current water resources situation of Hai River Basin. Five issues are analyzed: (1) the construction of conservancy projects; (2) the irrigation of farmland; (3)the safety of drinking water; (4)the protection of water environment; and (5)the model of management practice. Existing problems are diagnosed and possible solutions are discussed. Finally, a summary is made for managing water resources and meeting future needs.

• Water Engineering Research
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• v.5 no.4
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• pp.185-193
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• 2004

Estimates of annual actual evapotranspiration are needed in water balance studies, water resources management projects, and many different types of hydrologic studies. This study validated a set of 5 empirical equations of estimating annual actual evapotranspiration with climate data on 11 watersheds, and evaluated the further applicability of these forms in estimating annual runoff on watershed level. Five empirical equations generally overestimated annual evapotranspiration, with relative errors ranging $3.3\%$ to $47.2\%$. The results show that Schreiber formula can be applicable in determining annual evapotranspiration in sub-humid region that is classified by aridity index, while Zhang equation gave better results than the remaining methods in humid region. The mean differences for annual evapotranspiration bias over 11 watersheds are Zhang, Schreiber, Budyko, Pike, and Ol'dekop formula from lowest to highest. The empirical equations provide a practical tool to help water resources managers in estimating regional water resources on ungauged large watershed.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.06a
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• pp.12-13
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• 2020

Construction projects and buildings are becoming taller and larger, and the size of water tanks of production facilities and high-rise buildings is also gradually increasing. Most large water tanks apply a waterproofing layer to the water tank type concrete structure. The application of polyurea coating materials, which are excellent in water resistance, chemical resistance, physical performance, rapid hardening, and workability is gradually increasing as waterproofing and anticorrosion layer for water tank. As a result, defects such as water leakage and damage to the waterproofing layer are continuously occurring, causing production disruption, setback to users. Therefore, it is required to review suitability through performance verification of the waterproofing and anticorrosion system.

• Magazine of the Korean Society of Agricultural Engineers
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• v.45 no.6
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• pp.96-108
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• 2003

Agricultural water occupies the largest portion of total water use in Korea, and generally researches on the development of agricultural water have been stressed on the demand of agricultural water itself. But it is unavoidable to change a policy from the development of water resources to cope with the increase of water demand to the effective management of existing water resources. Evaluation of the decrepitude of irrigation facilities and their reasonable maintenance are important for the effective supply and use of agricultural water. Therefore it is necessary to develop evaluation technique that diagnoses the current condition of irrigation canals and suggest a countermeasure to improve the found problems. 25 items in 6 classes were selected for the evaluation of irrigation canal systems, and the weighted value between the items was calculated using AHP (Analysis Hierarchy Process) method. The current condition of the irrigation facilities was evaluated from the class evaluation marks, and ranking was decided from the total marks between the projects, and finally the priority of the project for the improvement was given.