• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회 논문집
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• pp.138-142
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• 2005

The change of precipitation and temperature due to the global. warming eventually caused the variation of water availability in terms of potential evapotranspiration, soil moisture, and runoff. In this reason national long-term water resource planning should be considered the effect of climate change. Study of AOGCM-based scenario to proposed the plausible future states of the climate system has become increasingly important for hydrological impact assessment. Future climate changes over East Asia are projected from the coupled atmosphere-ocean general circulation model (AOGCM) simulations based on Intergovernmental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios (SRES) A2 and B2 scenarios using multi-model ensembles (MMEs) method (Min et al. 2004). MME method is used to reduce the uncertainty of individual models. However, the uncertainty increases are larger over the small area than the large area. It is demonstrated that the temperature increases is larger over continental area than oceanic area in the 21st century.

• 한국항해학회지
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• 제14권3호
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• pp.15-33
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• 1990

In recent years, propellers with various blade configurations such as highly skewed propellers are often fitted to ships from the viewpoint of reduction of vibration and noise. In the design of such propellers, design charts based on methodical series tests are to be complemented by theoretical calculations for accurate estimation of propeller open-water characteristics. The author intended to develop a method to estimate propeller open-water characteristics based on Quasi -Vortex - Lattice Method originally developed by Lan for solving planar thin wings, The Quasi - Vortex - Lattice Method has the simplicity and flexibility of Vortex - Lattice Method. Its accuracy is comparable to that of the Vortex - Lattice Method. Converged solution can be obtained with a small number of control points and further, leading edge suction force can be calculated directly. In the present paper, a numerical method to estimate propeller open-water characteristics based on the Quasi - Vortex - Lattice Method is reviewed and its application to marine propellers is described in detail. Comparison of propeller open-water characteristics obtained by the present method with experimental data showed good agreement for a wide variety of propellers including highly skewed propellers.

• Water Engineering Research
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• 제1권3호
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• pp.233-242
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• 2000

A system for regularly appraising the reliability of streamflow data, KORSAS (KOwaco's Regular Streamflow Appraising System) was developed on PC based Windows for hydrological specialists and engineers working in the Korea Water Resources Corporation (KOWACO). The reliability of streamflow rates can be evaluated with KORSAS in various as pects according to the evaluation duration and method. The former being selected as short term (event based) or long term(continus based), and the latter being classified into comparison methods of flow measurement, other stations results, and simulation. Rainfall-runoff models can be used together with KORSAS in order to evaluate the reliability of observed flow data by comparing with simulated flow data. The objective of this study is to develop a systematic methodology in various aspects to evaluate the reliability of streamflow data regularly.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 D
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• pp.2115-2117
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• 2003

This paper is study on internet based wireless remote control and monitoring for the system to purify water. Environment of the water quality grew worse. Therefore we require the effective system to purify water. Now national internet based wireless remote control and monitoring make a sensation and are a problem to be solved. This paper demonstrate internet based wireless remote control and monitoring for the system to purify water. This system including on server and many client distributed in whole country. The server is collecting information from the client. This information is then written inside database. The database is dealing with website and server and client.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2016년도 학술발표회
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• pp.230-230
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• 2016

Hydrological modeling is a very complex task dealing with multi-source of data, but it can be potentially benefited from recent improvements and developments in remote sensing. The estimation of actual land surface evapotranspiration (ET), an important variable in water management, has become possible based entirely on satellite data. This study adopted a Surface Energy Balance Algorithm for Land (SEBAL) with the use of MODerate Resolution Imaging Spectrometer (MODIS) satellite products. The SEBAL model is one of the commonly used approach for the ET estimation. A primary advantage of the SEBAL model is rather its minimum requirement for ground-based weather data. The MODIS provides ET (MOD16) product that is based on the Penman-Monteith equation. This study aims to further develop the SEBAL model by employing a more rigorous parameterization scheme including the estimation of uncertainty associated with parameter and model selection in regression model. Finally, the proposed model is compared with the existing approaches and comprehensive discussion is then provided.

• Nuclear Engineering and Technology
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• 제52권12호
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• pp.2847-2851
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• 2020

A simple water level measurement method based on wavelength division multiplexing (WDM) is proposed and demonstrated. The measurement principle is based on the change of Fresnel reflection occurring at the end facet of the optical fiber tip (OFT). To increase the spatial resolution of water level sensing, a broadband light source (BLS) and an arrayed waveguide grating (AWG) are employed. The OFTs are multiplexed with the dedicated wavelength channels of AWG. By measuring all of the reflection powers reflected at the OFTs with a proposed on-site reflectometer, the water level can be monitored continuously for a fast emergency response. Moreover, it can be implemented easily with the commercially available optical components and devices with the simple configuration.

• 한국표면공학회지
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• 제55권2호
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• pp.38-50
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• 2022

As a low-cost and high-efficiency electrocatalysts with high performance and stability become a key challenge in the development of the practical use of water electrolysis, there is an intense interest in transition-metal oxalate-based materials. Transition-metal oxalate-based catalysts with excellent electrochemical performances have been widely applied in water electrolysis due to its low-cost and ease of synthesis. This review provides a useful summary on the development of transition-metal oxalate as potential catalysts for water electrolysis with a focus on the structural and compositional alteration, role of oxalate anion, and enhanced electrochemical performances.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회(1)
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• pp.145-146
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• 2005

• 환경영향평가
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• 제10권3호
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• pp.235-243
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• 2001

Since the middle of 1990s, in Korea a few researches on the optimal management technologies combining numerical model and GIS for the management of water environment in drinking watershed area and reservoir such as Paldang Lake have been carried out. In this study, the integrated water environment management system was been suggested to efficiently reflect the public awareness of the environment by integrating the web based distributed data collection system, GIS, public hearing system and water quality model. As all the components of the system have been developed using the World Wide Web and all data have been collected from the relevant agencies through the Internet, the water quality model could be implemented on the web directly. In consequence, the environmental geographic information in Paldang Lake could be acquired and analyzed through the Internet. The system can rapidly respond to the public right to know on environment, so the public will willingly participate in the governmental projects on environment. To verify the usability of the developed system, it has been applied to Paldang Lake. Especially when the web based model has been used, users can easily and confidentially get the prediction results by applying the minimum number of parameters for the water quality model. This model will provide clearness and scientific bases in the process of water quality prediction for the sensitive sites where there are critical conflicts between the residents and the developers. In this study, rapid water environment management technique without spatial and time limit has been suggested, which can contribute to the efforts on the government and the public participation.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2016년도 학술발표회
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• pp.204-204
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• 2016

Thailand had set the National Water Management Strategy which covered main six areas in the next 12 years, i.e., by priority: (1) water for household, (2) water for agricultural and industrial production, (3) water for flood and drought management, (4) water for quality issue, (5) water from forest conservation and soil erosion protection, (6) water resources management. However due to the climate change impact, there is a question for all strategies is whether to complete this mission under future climate change. If the impact affects our target, we have to clarify how to mitigate or to adapt with it. Vulnerability assessment was conducted under the framework of ADB's (with the parameters of exposure, sensitivity and adaptive capacity) and the assessments were classified into groups due to their different characteristic and the framework of the National Water Management Strategy, i.e., water supply (rural and urban), water for development (agriculture and others), water disasters (floods (flash, overflow), drought, water quality). The assessments identified the parameters concerned and weight factors used for each groups via expert group discussions and by using GIS mapping technology, the vulnerability maps were produced. The maps were verified with present water situation data (floods, drought, water quality). From the analysis result of this water resources management strategy, we found that 30% of all projects face the big impacts, 40% with low impact, and 30% for no impact. It is clear that water-related agencies have to carefully take care approximately 70% of future projects to meet water resources management strategy. It is recommended that additional issues should be addressed to mitigate the impact from climate risk on water resource management of the country, i.e., water resources management under new risk based on development scenarios, relationship with area-based problems, priority definition by viewpoints of risk, vulnerability (impact and occurrence probability in past and future), water management system in emergency case and water reserve system, use of information, knowledge and technology in management, network cooperation and exchange of experiences, knowledge, technique for sustainable development with mitigation and adaptation, education and communication systems in risk, new impact, and emergency-reserve system. These issues will be described and discussed.