• Nuclear Engineering and Technology
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• v.44 no.3
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• pp.311-322
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• 2012

Since the crisis at the Fukushima plants, severe accident progression during a station blackout accident in nuclear power plants is recognized as a very important area for accident management and emergency planning. The purpose of this study is to investigate the comparative characteristics of anticipated severe accident progression among the three typical types of nuclear reactors. A station blackout scenario, where all off-site power is lost and the diesel generators fail, is simulated as an initiating event of a severe accident sequence. In this study a comparative analysis was performed for typical pressurized water reactor (PWR), boiling water reactor (BWR), and pressurized heavy water reactor (PHWR). The study includes the summarization of design differences that would impact severe accident progressions, thermal hydraulic/severe accident phenomenological analysis during a station blackout initiated-severe accident; and an investigation of the core damage process, both within the reactor vessel before it fails and in the containment afterwards, and the resultant impact on the containment.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.05a
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• pp.284-287
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• 2022

In order to respond to the complexity and uncertainty of water management due to the climate crisis, K-water established a digital twin water management platform based on our experience in operating ICT infrastructure such as hydrological data sensing and high-quality data management and water management capabilities. In this platform, data from related organizations and real-time observation data in the basin are displayed on 3D topographic domain. Also it is configured to support optimal decision-making through simulation for various situations, displaying and analyzing results, and feedback on them. It is completed to establish the platform for Sunjim river basin. Based on this technologies and experience, K-water is planning to expand this digital twin to 5 major rivers in Korea. Through this, it plans to build comprehensive decision-making system for efficient water management considering various conditions in entire basin. Also it aims to create a new water industrial ecosystem and contribute to secure technological competitiveness cooperating with private companies.

• Journal of Hydrogen and New Energy
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• v.19 no.1
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• pp.1-9
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• 2008

Human has faced in lack of fossil fuel and environmental crisis because of high population growth and development of industry. Hydrogen, unlimited amount and clean resource from water electrolysis, is remarkably known as the solution of recent energy crisis. One of the special characteristics of hydrogen is that a little amount of catalytic such as platinum and palladium makes nonflammable combustion, in other words catalyst combustion. Catalytic combustion fueled by hydrogen is environmentally friendly. This paper considers some comparisons of characteristic of catalytic combustion between a single layer of platinum catalyst, double layer of platinum and nickel catalysts and mixture of platinum and nickel catalysts. Some experiments of temperature distribution at different positions and characteristic of combustion in low temperature region were done in order to find an applicable possibility as a house-cooking burner.

• Journal of Hydrogen and New Energy
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• v.9 no.1
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• pp.38-45
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• 1998

An energy crisis is expected in near future. Fossil fuel such as oil and natural gas has been used and will be no longer supplied enough to demand in the beginning of coming century. The use of the fuel makes a lot of environmental pollution to threaten human being's health especially in big cities and produces a lot of $CO_2$ to make green house effect of the earth. It is the time to use clean fuel such as hydrogen to prevent the expected energy crisis and the pollution. A new engine such as fuel cell can be used instead of the conventional internal combustion engine with 2 to 3 times higher efficiency of the conventional engine. The fuel cell uses hydrogen and oxygen and produces electric energy and pure water, which is a calm engine without air pollution. In big cities the city buses and the taxies powered by hydrogen fuel cells are suggested to be operated for clean environment. A model of the total energy system for production, transportation and utilization of hydrogen is calculated.

• Proceedings of the Korean Society of Environment and Ecology Conference
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• 2003.10a
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• pp.23-29
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• 2003

It has been declared in 1992 at Rio about the management of united water control and method of the management of the water resources at the water basin. And it was also mentioned about the protection of fresh water's quality and it's supply under chapter the 18th of the agenda 21. It has been 10years passed after Rio declaration, and water crisis Is getting more serious than before. Fairly, right for using water resources was given to every life as the public resources. But at the last world water forum, water was commercialized, and regulated as the basic requirement not basic right. Therefore, we could use the water according to the logic of supply and demand at the market, and with money. Furthermore, construction of the big dam which was build to solve the problem of the lack of water became one of problems for water control. Korea is keeping consistent policy such as providing water by the building of dam. Control of the water demand is the most basic and effective policy for the preservation of water resources. If we change the policy such as the construction of the dam, we should put the management of the water demand in the center with the reliable philosophy. United management of the river basin has to be made with the security of water, improvement of water quality, and protection of the ecological side each other. Management of water basin also has to be completed to solve the trouble caused by using water conflict people who live up and down stream. To maintain the good quality of water, management of water basin is necessary. Also, bottom line of the united management of water basin is voluntary involvement of every citizens and local community. We suggest to preserve the origin of river and the upper at the ecological side. It is worth it to preserve.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.1348-1351
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• 2006

Recently human beings face serious water crisis, namely water management at the critical moment because of rapid increasing in population, subordinate part of a national budget, water pollution by domestic use and industrial use or waste, agricultural water use by intensive market farming, excessive development and extraction of water sources, and etc. We become to recognize that water and sanitation is the one of most important part which is threatening us with a drain on the water resources and death around the world and then are making opportunities of discussion for water policies and solutions of water problems through international network such as Global Water Partnership(GWP), World Water council(WWC). World Water Forum(WWF), as one of main water-related activities, aims at sharing knowledge and experience among various stakeholders for accomplishing a holistic water resources management by making common thoughts regarding the necessity of integration among different organizations related with water management, problems and issues. Also the unity of each local area for the holistic approach focuses on showing present local actions and actively supporting them, and suggesting new ideas. With Korea's participation in the 4th WWF this year, Korean government should have consistency in its establishment and implementation of sustainable water resources policies as a more active and future-oriented member of international water network. Finally it will be necessary that we will set up an organization and system which does publicity activities about results of various local actions of Korea around the world through next WWF in the future and contribute to solving global water problems.

• Journal of the Semiconductor & Display Technology
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• v.23 no.1
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• pp.12-18
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• 2024

The accelerated pace of climate crisis due to continuous industrialization and greenhouse gas emissions necessitates sustainable solutions that simultaneously address mitigation and adaptation to climate change. Naturebased Solutions (NbS) have gained prominence as viable approaches, with Green Infrastructure being a representative NbS. Green Infrastructure involves securing green spaces within urban areas, providing diverse climate adaptation functions such as removal of various air pollutants, carbon sequestration, and isolation. The proliferation of Green Infrastructure is influenced by the quantification of improvement effects related to various projects. To support decision-making by assessing the climate vulnerability of Green Infrastructure, the U.S. Department of Agriculture (USDA) has developed i-Tree Tools. This study proposes a comprehensive evaluation approach for climate change adaptation types by quantifying the climate adaptation performance of urban Green Infrastructure. Using i-Tree Canopy, the analysis focuses on five urban green spaces covering more than 30 hectares, considering the tree ratio relative to the total area. The evaluation encompasses aspects of thermal environment, aquatic environment, and atmospheric environment to assess the overall eco-friendliness in terms of climate change adaptation. The results indicate that an increase in the tree ratio correlates with improved eco-friendliness in terms of thermal, aquatic, and atmospheric environments. In particular, it is necessary to prioritize consideration of the water environment sector in order to realize climate change adaptive green infrastructure, such as increasing green space in urban areas, as it has been confirmed that four out of five target sites are specialized in improving the water environment.

• Journal of Environmental Policy
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• v.2 no.1
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• pp.1-29
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• 2003

This paper examines the dynamics of environmental policy development in Korea by reviewing some of the ways on how the policy windows have been opened. There are a lot of theoretical arguments about the major factors influencing policy development or changes. Many scholars have believed that severe pollution accidents or salient environmental episodes might have been the main motivation of environmental policy development. This line of argument seems valid, especially with the water pollution control policy in Korea. Water pollution control programs had rapidly expanded along with the series of water pollution accidents in the tap water sources from the late 1980s to mid-1990s. However, regarding other major env. issues, various other factors have played more important roles in the development of the relevant policies. In case of air pollution control policy international sport events such as, 1986 Asian Games, 1988 Summer Olympics, and 2002 World Cup Competition, have contributed for the development. The municipal solid waste management policy partly owed its development to the introduction of local autonomy system in the mid-1990s. Even the foreign currency crisis occurring in December 1997 helped the policy paradigm shift from rigid supply-oriented to soft demand-oriented approaches. After closely looking at the dynamics of environmental policy development in Korea, this paper tries to identify the logical background of the observed outcomes.

• Membrane and Water Treatment
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• v.5 no.1
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• pp.15-29
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• 2014

Reverse Osmosis (RO) desalination has gained wide and increasing acceptance around the world as a straightforward undertaking to alleviate the alarming water crisis. An enhanced monitoring of the quality of the water feeding in seawater RO (SWRO) plant through the application of an effective pretreatment option is one of the keys to the success of RO technology in desalination plants. Over the past 10 years, advances in ultrafiltration (UF) membrane technologies in application for water and wastewater treatment have prompted an impetus for using membrane pretreatment in seawater desalination plants. By integrating SWRO plant with UF pretreatment, the rate of membrane fouling can be significantly reduced and thus extend the life of RO membrane. With the growing importance and significant advances attained in UF pretreatment, this review presents an overview of UF pretreatment in SWRO plants. The advantages offered by UF as an alternative of pretreatment option are compared to the existing conventionally used technologies. The current progress made in the integration of SWRO with UF pretreatment is also highlighted. Finally, the recent advances pursued in UF technology is reviewed in order to provide an insight and hence path the way for the future development of this technology.

• Solar Energy
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• v.18 no.3
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• pp.81-87
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• 1998

Solar energy has been experiencing renewed interest because of the recent economical crisis in Korea. Absorption cooling is one of the promising solar energy utilization technologies. In this study the dynamic performance of a solar driven absorption cooling machine(SDACM) was numerically investigated. The simulated machine is a commercially available water/LiBr single effect absorption chillers driven by hot water from solar collectors. The present study has been directed to investigate the dynamic behavior of a solar cooling system including an absorption chiller, solar collector, a hot water storage tank, fan coil units, and the air-conditioned space. The operation of the system was simulated for 9 hours in varying operation conditions. The variation of temperature and concentration in the system components, and that of heat transfer rates in the system were obtained. It was also found that the room temperature was maintained near the desired value by controlling the mass flow rate of hot water.