• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1994.11a
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• pp.68-77
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• 1994

The Integrated Gasification Combined Cycle(IGCC) power plant is one of Clean Coal Technology to meet the demand for clean and efficient electric power for the 21st century. This study is to investigate the impacts of changes in coal quality to the performances of gasification processes and IGCC plants. The selection of the most economic coal is an important attribute for the IGCC power generation technology. The performances of gasification processes was predicted, and compared with the results of Shell coal gasification demonstrantions. The IGCC performances with bituminous and sub-bituminous coal were predicted as well. It is obtained that the bituminous coal is superior to the sub-bituminous coal for IGCC power generation.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1994.11a
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• pp.135-140
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• 1994

An improved steam generator model has been developed for the DSNP simulation of normal operational transient behavior of CANDU nuclear power plant. For more realistic prediction of steam generator behavior during transient, tube bundle region is divided into two separate control volumes, subcooled region and saturated region, and the variation of thermal hydraulic properties in the control volume is accounted for more realistic estimates of outlet enthalpy of each control volume. Test results for typical CANDU operational transient case show reasonable transient behavior of steam generator with overall CANDU operation and improved operational characteristics of steam generator with power variation.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1999.11a
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• pp.149-154
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• 1999

This paper describes a passive safety injection system with free piston Stirling pump working withabundant decay heat in the nuclear reactor during the hypothetical accident. The water column in the tube assembly connected from the hot chamber to the cold chamber in the pump oscillates periodically due to thermal volume changes of non-condensable gas in each chamber. The oscillating pressure in the water column is converted into the pumping power with a suction-and-bleed type valve assembly. In this paper a dynamic model describing the frequency of oscillation and pumping pressure is developed. It was found that the pumping pressure is a function of the temperature difference between the chambers. Also, the frequency oscillation depends on the length of the tube with water column.

• Journal of Radiation Industry
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• v.5 no.4
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• pp.285-295
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• 2011

Mushrooms belonging to macrofungi have been consumed by humans for their nutritional and medicinal values for centuries throughout the world. Mushroom farming is practiced in more than 100 countries of the world, with production increasing at a rate of 7% per annum. High yield and good quality are always the principal goals for agriculturally important crops, including mushrooms. Several breeding methods are employed for strain improvement such as mass selection based on the natural chance mutation and induced mutation (mutation breeding), protoplast fusion technology, cross breeding and transgenic breeding. However, mutation breeding has shown prominent success in crop plant improvement. Though several-hundred mutant crop varieties have been developed around the world, the mutation breeding of mushrooms is limited. This review paper explores the potential application of radiation on the development of mutant varieties of mushrooms for breeding with desired traits such as better quality and productivity.

• Corrosion Science and Technology
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• v.18 no.5
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• pp.190-195
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• 2019

SA508 low-alloy steel for a reactor vessel was exposed to primary water in a pressurized water reactor (PWR) plant because the cladding layer of type 309 stainless steel for the RPV was removed, due to an accident in which the detachment of the thermal sleeve occurred. The major advantage of the electrochemical deposition (ECD) Ni plating technique is that the reactor pressure vessel can be repaired without significant thermal effects, and Ni has solid corrosion resistance that can withstand boric acid. The corrosion rate assessment of the damaged part was performed, and its trend was analyzed. Essential variables of the Ni plating for repair of the damaged part were derived. These conditions are applicable variables for the repair plating device, and have been carefully adjusted using the repair plating device. The process for establishing ASME technical standards called Code Case N-840 is described. The process of developing Ni-plating devices, and the electroplating procedure specification (EPS) are described.

• Journal of the Korean Solar Energy Society
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• v.28 no.5
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• pp.72-77
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• 2008

The purpose of this paper is to explain the real characteristics of generation system of large scale power system of high voltage the grid connected PV power system for electricity industry. Main system is made up PCS in the class 150kVA. and we studied commercial operation in Korea-Western Power Company,(Tae-An headquarter) with the capacity of module is 122.5 $kW_p$. On the average, power plant utilities' utilization is 12.71 percent and consumption rate is 6.66 percent. We operated normally since 25th, August 2005 without any other problems.

• Nuclear Engineering and Technology
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• v.36 no.5
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• pp.430-449
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• 2004

A quantitative model for a control system that integrates human operators, systems, and their interactions is developed based on discrete functions. After identifying the major entities and the key factors that are important to each entity in the control system, a quantitative analysis to estimate the recovery failure probability from an abnormal state is performed. A numerical analysis based on assumed values of related variables shows that this model produces reasonable results. The concept of 'relative sensitivity' is introduced to identify the major factors affecting the reliability of the control system. The analysis shows that the hardware factor and the design factor of the instrumentation system have the highest relative sensitivities in this model. T도 probability of human operators performing incorrect actions, along with factors related to human operators, are also found to have high relative sensitivities. This model is applied to an analysis of the TMI-2 nuclear power plant accident and systematically explains how the accident took place.

• Nuclear Engineering and Technology
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• v.8 no.4
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• pp.219-229
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• 1976

A statistical approach is employed to investigate the relative advantages of several alternative fuel cycles suitable for a hypothetical 1125 MWe plant in Korea. All the fuel cost parameters are treated as statistical variables, each being associated with an appropriate probability distribution function. Through a random sampling procedure, the probability histograms on both capital requirements and break-even costs of various fuel cycle components are obtained. The histograms are then utilized to quantify the cost-benefit of the fuel cycle with reprocessing or the plutonium recycle over the throwaway cycle.

• Nuclear Engineering and Technology
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• v.45 no.4
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• pp.553-564
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• 2013

This study evaluates the local damage of a turbine in an auxiliary building of a nuclear power plant due to an external impact by using the LS-DYNA finite element program. The wall of the auxiliary building is SC structure and the material of the SC wall plate is high manganese steel, which has superior ductility and energy absorbance compared to the ordinary steel used for other SC wall plates. The effects of the material of the wall, collision speed, and angle on the magnitude of the local damage were evaluated by local collision analysis. The analysis revealed that the SC wall made of manganese steel had significantly less damage than the SC wall made of ordinary steel. In conclusion, an SC wall made of manganese steel can have higher effective resistance than an SC wall made of ordinary steel against the local collision of an airplane engine or against a turbine impact.

• Journal of Hydrogen and New Energy
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• v.30 no.1
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• pp.29-34
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• 2019

Safety of hydrogen handling facilities is needed as supply of hydrogen cars has been expanded recently. In this study, the adequacy of safety regulations of hydrogen handling facilities and the risk of damage with hydrogen leakage were studied. The range of explosion hazard location of the hydrogen filling plant was investigated using the computational fluid dynamics (CFD) method, Explosive hazardous area is influenced by leakage type, hole size and sectional area. When the conditions of KS standard are applied, range explosive hazardous area is expanded 7.05 m, maximum. It is about 7 times larger than exceptional standard of hydrogen station. Meanwhile, distance from leakage point to 25% LEL of hydrogen is investigated 1.6 m. Considering the shape of charging hose, regulation of hydrogen station is appropriate.