• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.24 no.3
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• pp.227-235
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• 2014

The demand of natural gas is gradually increasing as a clean fuel in the world. Therefore, LNG storage tanks and related facilities of the importance of leading a community-based facility have emerged. The seismic design of LNG storage tank including seismic analysis have been developed steadily. But, the seismic analysis and design techniques for LNG storage tanks are lacking, in Korea. Consequently, it is necessary to develop an analysis model that LNG storage tanks in isolation system can describe the behavior. Further, LNG storage tank capable of ensuring safety and economy, it is necessary to develop design techniques. The studies have suggested seismic design procedures of LNG storage tanks with isolation system including triple-FPB and idealized complex hysteresis model of triple-FPB.

• Journal of Korean Society of Water and Wastewater
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• v.22 no.3
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• pp.343-350
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• 2008

Many reports have warned of insufficient water supply in most countries in future and prospected providing safe and clean water become more difficult by lack of access to sustainable drinking water resources. Several facts and figures explained the impact by natural climate change and human activity results in the water scarcity and deterioration. Among many scientific solutions, the seawater desalination using a reverse osmosis membrane, so called SWRO (Seawater Reverse Osmosis) process, has been recognized as one of the most promising alternatives because of its stability and efficiency in producing large amount of drinking water from seawater through desalination by membrane filtration. Recently, in Korea, numerous researches are conducted to develop more productive and cost effective SWRO process for its wide implementation. The objective of this paper is to review the patents concerning SWRO technologies involving the plant engineering, maintenance including pretreatment of seawater and fouling control, module design, and mechanical units development for energy saving. The patents in Korea, U.S., Japan, Europe, and PCT were intensively researched and analyzed to provide the state of the art as well as leading edge technology on SWRO. This information can hopefully suggest meaningful guidelines on future research and development.

• Journal of the Korean Institute of Gas
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• v.15 no.4
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• pp.33-38
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• 2011

The introduction of alternative fuels is beneficial to overcome the fuel shortage and reduce engine exhaust emissions. LPG and CNG are relatively clean fuel and considered as most promising alternative automotive fuels worldwide because of its emission reduction potential and lower fuel price compared to gasoline. Now a day’s adaptation of dual fuel approach is the growing as common trend. The two fuels can be successfully implemented with existing gasoline engine with little modification. The present study was done to analyze the performance and emissions analysis of a multi cylinder spark ignition engine fuelled with the benefits of CNG and LPG aseffective alternate automotive fuels by simply using them in an unmodified petrol engine. The test results indicate, the energy content of CNG and LPG is the most limiting factor in acceptance for fuel economy and performance reasons. Thermal efficiency was high for CNG lowest for gasoline and LPG between the two. BSFC, CO and HC were low and NOx was high for CNG and low for gasoline, LPG lies between the two.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.5
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• pp.469-473
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• 2003

Transplantation of Sargassum horneri to natural substrate using the rope seeding method was undertaken. Seeding of S. horneri was grown on net in an indoor tank up to 0.2-0.3 cm in frond length for 2 months, and then transplanted to an architecture tile $(10\times10\;cm)$ with underwater glue and an iron pipe. After two months, number of S. horneri on the tile decreased because of grazing by herbivores. However, S. horneri on the iron pipe grew up to 0.5-2.0 cm in frond length. After 7 months, they rapidly grew up to a frond length of 11.0-203.0 cm with a mean frond length of 122.6 cm. S. horneri grew up to a maximum frond length of 313.0 cm, and mean frond length of 228.0 cm, after 10 months. The artificial S. hornevi beds can be used to clean the seawater and also be utilized as a source of marine biomass as well as for supplying habitat, shelter and spawning beds for fish and invertebrates.

• Journal of Korean Society on Water Environment
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• v.21 no.2
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• pp.109-117
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• 2005

Understanding the condition of our nation's water resources, identifying what caused problems, and determining how to solve these problems are essential but difficult undertakings. The natural water cycle is itself intricate, and the addition of human activities increased this complexity. Consequently, answering the basic question "How clean and safe is our water?" is not easy. One way to present the condition of our water resources and the impacts of related human activities is to develop understandable measures, or indicators, that singly or in combination provide information on water quality. Managers and scientists can then use this information to develop effective solutions and make sound decisions to protect our water resources. It is important to note that environmental indicators can be used to measure a variety of phenomena. Indicators can present information on status or trends in the state of the environment, can measure pressures or stressors that degrade environmental quality, and can evaluate society's responses aimed at improving environmental conditions.

• 한국신재생에너지학회:학술대회논문집
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• 2008.10a
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• pp.216-219
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• 2008

As a future clean substitute energy, the Gas hydrate development projects are world widely carried out to prepare the shortage of petroleum and natural gas resources. The OIIP of gas hydrate is estimated approximately 10 Trillion LNG equivalent ton and it reaches almost the amount of 5 thousand years use for the world people. To develop the commercial production technology, several research projects like Malik and Alaska project have been carried by several advanced countries and teams, but nobody have succeeded it yet due to the technical problems and the high risks. The technologies developed up to now for the hydrate production are categorized to four methods, such as depressurization method, thermal recovery method, inhibitor injection method and replacement method. As these methods are highly related to the costs and the environmental problems, many other researches including the safety, environment and disaster prevention are actively fulfilled as well.

• Journal of the Korean institute of surface engineering
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• v.27 no.3
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• pp.158-165
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• 1994

Cu-Cr alloy thin film requires good quality of etching be used for TAB technology. The etched cross sec-tion was clean enough when the etching was performed in 0.1M $FeCl_3$ solution at $50^{\circ}C$. The etching rate was increased with the amount of $KMnO_4$. For enhanced profile of cross section and rate, the spray etchning was found to be superior compared to the immersion etching. A series of experiments were performed to improve the uniformity of the current distribution in electrodeposition onto the substrate with lithographic patterns. Copper was electrodeposited from quiescent-solution, paddle-agitated-solution, and air-bubbled-solution to in-vestigate the effect of the fluid flow. The thickness profile of the specimen measured by profilmetry has the non uniformity at feature scale in quiescent-solution, because of the longitudinal vortex roll caused by the natural convection. However, uniform thickness profile was achieved in paddle-agitated or air bubbled solu-tion.

• Transactions of the Korean hydrogen and new energy society
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• v.19 no.5
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• pp.445-452
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• 2008

DME(Dimethyl ether) Dimethyl Ether (DME) is a new clean fuel and an environmental-benign energy resource. In comparison with other fuels, DME rapidly decomposes into carbon dioxide ($CO_2$) and water in the atmosphere without forming ozone. It can be manufactured from various energy sources including natural gas, coal, biomass and spent plastics. In addition to its environmentally friendly properties, DME is considered as one of the most promising candidates for the substitute of LPG and diesel fuel. In this work, we will be studied to find optimized condition for the catalyst of DME energy manufacture from hydrogen and carbon oxide and its chemical and physical characteristics.

• Proceedings of the KIEE Conference
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• 2002.07d
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• pp.2617-2618
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• 2002

The key point of this design can offer good picture resolution and a high-speed color STN decode. We maximize a combination processing of the color signal. Therefore, there is a color implementation at the natural. The age of the multimedia comes, so the color is considered important and wide. To be necessary a color implementation have become the importance which picture resolution is clean and low price of the liquid display TFT occupied greater part of the liquid display. But TFT could not consist low price realization. This research is a color implementation of STN at low price, design good picture resolution decode for optimum an limit of upside with frequency range maximizing and can reply in the high-speed by multidivision method. As a result, we design optimum of the STN decode.

• Proceedings of the KIEE Conference
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• 2006.07b
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• pp.773-774
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• 2006

Nowadays, the global interests are concentrated on the preserving of the clean environment, and the diminishing of the dependence on the fossil energy, and among the possible alternative energies, the wind turbine generating system is considered to be the best suited to produce high efficiency energy, without affecting the natural environment. The permanent magnet generators were been used for the wind power generating, for long time, with continuous efforts to improve the generating efficiency. And the latest trend on it is to develop an AFPM(Axial Flux Permanent Magnet)type, which is composed in the structure of rotor and stator shaped in the disc forms, and the direction of the flux at the air gap runs in parallel to the shaft. This thesis is on the study concerning with the analysis of the characteristics of the 5 kW at 300rpm direct drive AFPM generator which is suitable for the small scale wind turbine generating system. In it, the Electro-magnetically Coreless AFPM was been analyzed, the prototype generators been made, concentrated on interpreting the characteristics of the power output, and verifying it through the theoretical study and practical tests.