• Corrosion Science and Technology
• /
• 제7권2호
• /
• pp.77-84
• /
• 2008

Based upon the good compatibility to neutron irradiation and high temperature water environment, austenitic stainless steels are widely used for core internal structural materials of light water reactors. But, recently, intergranular cracking was detected in the stainless steels for the core applications in some commercial PWR plants. Authors studied on the root cause of the intergranular cracking and developed the countermeasure including the alternative materials for these core applications. The intergranular cracking in these core applications are defined as an irradiation assisted mechanical cracking and irradiation assisted stress corrosion cracking. In this paper, the root cause of the intergranular cracking and its countermeasure are summarized and discussed.

• 한국막학회:학술대회논문집
• /
• 한국막학회 1995년도 추계 총회 및 학술발표회
• /
• pp.74-79
• /
• 1995

In the last 10 years, membrane science and technology in Korea have grown fast in terms of basic research and process applications. Even the first large commercial membrane plant in Korea was an ion-exchange membrane process built in 1975 for the production of table salt with an annual capacity of 150,000 tons of salt, membrane processes could not draw general interests from industry not until 1987 when a reverse osmosis plant for the production of process water with a capacity of 10,000 m$^3$/day was built by Kugdong Petroleum Co. Today, the production of water by RO over the capacity of 140,000 m$^3$/day is in operation or under construction in Korea. Consumption of ultra pure water increases sharply in recent years mainly due to the rapid expansion of semiconductor industry and the introduction of ultra high pressure boilers for power plants.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제11권7호
• /
• pp.3465-3479
• /
• 2017

Information-Centric Vehicular Ad Hoc Network (IC-VANET) is a promising network architecture for the future intelligent transport system. Video streaming applications over IC-VANET not only enrich infotainment services, but also provide the drivers and pedestrians real-time visual information to make proper decisions. However, due to the characteristics of wireless link and frequent change of the network topology, the packet loss seriously affects the quality of video streaming applications. In this paper, we propose a REceiver-Driven loss reCOvery Mechanism (REDCOM) to enhance video dissemination over IC-VANET. A Markov chain based estimation model is introduced to capture the real-time network condition. Based on the estimation result, the proposed REDCOM recovers the lost packets by requesting additional forward error correction packets. The REDCOM follows the receiver-driven model of IC-VANET and does not require the infrastructure support to efficiently overcome packet losses. Experimental results demonstrate that the proposed REDCOM improves video quality under various network conditions.

• 한국표면공학회지
• /
• 제56권6호
• /
• pp.443-450
• /
• 2023

SiC/SiC_f CMC is vulnerable to water vapor corrosion at a high temperature of 1500℃. So, EBC (Environmental Barrier Coating) materials are required to protect Si-based CMCs. Ytterbium silicates are reported to have coefficient of thermal expansion (CTE) similar to that of the base material, such as SiC/SiC_f CMC. When the EBC are materials exposed to high temperature environment, the interface between ytterbium silicates and SiC/SiC_f CMC is not separated, and the coating purpose can be safely achieved. For the perspective of EBC applications, thermally grown oxide (TGO) layer with different CTE is formed by the reaction with water vapor in EBC, which leads to a decrease in life time. In this study, we prepare two types of ytterbium silicates to observe the corrosion behavior during the expose to high temperature and water vapor. In order to observe this behavior, the steam-jet furnace is prepared. In addition, phase formation of these ytterbium silicates is analyzed with microstructures by the before/after steam-jet evaluation at 1500℃ for 100 h.

• Membrane and Water Treatment
• /
• 제13권6호
• /
• pp.259-290
• /
• 2022

Carbon nanotubes (CNTs), due to their excellent physical, chemical and mechanical properties and their ability to prepare new membranes with attractive properties, have found applications in water and wastewater technology. CNT functionalization, which involves the introduction of different types of functional groups into pure CNTs, improves the capabilities of CNT membranes for water and wastewater treatment. It turns out that CNT-based membranes have many advantages, including enhanced water permeability, high selectivity and anti-fouling properties. However, their full-scale application is still limited by their high cost. With their tremendous separation efficiency, low biofouling potential and ultra-high water flux, CNT membranes have the potential to be a leading technology in water treatment in the future, especially in desalination.

• 청정기술
• /
• 제27권3호
• /
• pp.217-222
• /
• 2021

Although monolayer black phosphorus (BP) and few-layer BP nanosheets (NSs) have been extensively studied as promising alternatives to graphene, research has focused primarily on atomically thin-layered BP in an isolated form. In order to realize the practical applications of BP-related devices, a BP film based on continuous networking of few-layer BP NSs should be developed. In this study, a transparent BP film with high quality was fabricated via a vacuum filtration method. An oxygen-free water solvent was used as an exfoliation medium to avoid significant oxidation of the few-layer BP NSs in liquid-phase exfoliation. The exfoliation efficiency from bulk BP to the few-layer BP NSs was estimated at 22%, which is highly efficient for the production of continuous BP film. The characteristics of the high-quality BP film were determined as 98% transparency, minimum oxidation of 18%, structural stability, and an appropriate bandgap of about 1.8 eV as a semiconductor layer. In order to demonstrate the potential of the BP film for photocatalytic activity, we performed photoelectrochemical water oxidation of the transparent BP film. Although its performance should be improved for practical applications, the BP film could function as a photoanode, which offers a new potential semiconductor in water oxidation. We believe that if the BP film is adequately engineered with other catalysts the photocatalytic activity of the BP film will be improved.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2005년도 춘계 학술발표회 논문집
• /
• pp.1420-1425
• /
• 2005

In a case of an example in Korea, some areas of Yangsan near Busan which exist on soft ground with aquifer, showed us some difficulties of the preparing for housing site and earth structures. From these experiences, recently, the development and research of technology is getting increased, which minimize the influence to the environment from construction work, which is in an agreement with eco-friendly construction in terms of the reasonable processing of ground water. On this case study, one area of Japan that has many site on soft ground with aquifer, is introduced as the reasonable processing of ground water. The applications of the technology for ground water in Korea are discussed.

• 한국막학회:학술대회논문집
• /
• 한국막학회 2004년도 춘계 총회 및 학술발표회
• /
• pp.147-152
• /
• 2004

Gas separation membrane technology is useful for a variety of applications [1, 2]. such as hydrogen recovery from reactor purge gas, nitrogen and oxygen enrichment, water vapor removal from air, stripping of carbon dioxide from natural gas. etc. Although membrane separations are attractive because of low energy costs and simple operation, low permeabilities and/or selectivity often limit membrane applications [3, 4].(omitted)

• 멤브레인
• /
• 제11권3호
• /
• pp.97-108
• /
• 2001

Bipolar membranes have gained increasing interest as a tool for an efficient production of acids and bases from the corresponding salts. A large number of potential applications have been identified in the chemical and biochemical industry have been identified and evaluated on a laboratory scale. In spite of extensive research efforts and laboratory and pilot plat test, there are hardly any large-scale commercial plants. In this paper the basic concept of the electrodialytic water dissociation with bipolar membranes are briefly reviewed. The limitations of today\`s bipolar membranes are indicated. Selected examples of successful applications of the bipolar membrane technology are discussed.

• 한국수자원학회:학술대회논문집
• /
• 한국수자원학회 2016년도 학술발표회
• /
• pp.578-578
• /
• 2016

In the past decade, many countries developed varies promising theories, methodologies and technologies for water resources management, such as Smart Water in Korea, eWater in Australia, Intelligent Water in Untied States, and Internet of Water in China. It is no exaggeration to say that Smart Water Management(SWM) will have a major role to play in addressing the global water challenges in the background of climate change, population growth and rapid urbanization. As a result, we can see major shifts taking place in the structure of the water industry, with a need for new approaches, skills, and water management policies. All these point towards a brighter future for the smart water sector and a new water paradigm, with applications and potential throughout the water cycle. However, each countries have their technology and industry standard system which may swift similar innovation and technology into different channels. In that sense, developing a common performance index and standard docking adapter for assessing Smart Water Management Initiatives(SWMI) is crucial for drawing a linkage of SWMI and SWMs to a way to implement advanced technology across Asia and Pacific. The performance index and standard docking adapter will facilitate quantitative and qualitative effects of utilized SWM techniques.