• Nuclear Engineering and Technology
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• v.28 no.5
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• pp.467-481
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• 1996

An integrated framework of modeling the human operator cognitive behavior during nuclear power plant accident scenarios is presented. It incorporates both plant and operator models. The basic structure of the operator model is similar to that of existing cognitive models, however, this model differs from those existing ones largely in too aspects. First, using frame and membership function, the pattern matching behavior, which is identified as the dominant cognitive process of operators responding to an accident sequence, is explicitly implemented in this model. Second, the non-task-related human cognitive activities like effect of stress and cognitive biases such as confirmation bias and availability bias, are also considered. A computer code, OPEC is assembled to simulate this framework and is actually applied to an SGTR sequence, and the resultant simulated behaviors of operator are obtained.

• Journal of Power System Engineering
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• v.10 no.3
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• pp.32-37
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• 2006

In this paper, we present the flow and heat transfer characteristics with the array of impinging jet nozzles by using the numerical computation and experiment. Numerical solutions were obtained for dimensionless gap H=6, dimensionless outlet length L=10 and Reynolds number Re=1500 by using the commercial CFD code, CFX-5. Experimental and numerical results were agreed well with each other. It was found that the impinging jet with circular array nozzles generated the uniform heat transfer area and the maximum heat transfer is higher than rectangular array nozzles for certain parameter sets. It is one of the most important utilities providing steam to turbine in order to supply mechanical energy in thermal power plant. It is composed of thousands of tubes for high efficient heat transfer.

• Journal of the Korean Society of Combustion
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• v.12 no.4
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• pp.57-61
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• 2007

The aim of this study is to find out the condition that generates maximum $H_2$ through the calculation of equilibrium model with conditions of pyrolysis gases of Refuse Plastic Fuel(RPF). This study deals with the computational simulation of a RPF gasification using an equilibrium model based on minimization of the Gibbs free energy. An equilibrium analysis was carried out to determine species composition of Syngas in RPF gasification and reactions to variation of temperature, $O_2/Fuel$ ratio and Steam/Fuel ratio. Calculated results shows that hydrocarbons in pyrolyzed gas are converted to synthesis gas which is formed on hydrogen and carbon monoxide.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.137.2-138
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• 2003

The steam distillate obtained from sawdust of Thujopsis dolabrata var. hondai was fractionated by centrifugal thin-film evaporation. and then the fractions were investigated against antiplatelet activity using washed rabbit platelets in vitro. The biologically active constituent of T. dolabrata sawdust was isolated by silica gel column chromatography and HPLC and characterized as carvacrol by various spectral analysis ($^{1}H$, $^{13}C$-NMR and GC/MS studies). (omitted)

• Membrane and Water Treatment
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• v.5 no.2
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• pp.87-108
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• 2014

Electrodeionization (EDI), which combines electrodialysis (ED) and conventional ion-exchange (IX), is a mature process which has been applied since more than twenty years on commercial use for the production of ultrapure water (UPW). Eliminating chemical regeneration is the main reason for its commercial success. The increase in acceptance of EDI technology has led to an installation of very large plant as the commercial state of the art that produces $1,500m^3/h$ of water for high pressure steam boiler. More recently, EDI system has found a number of new interesting applications in wastewater treatment, biotechnology industry, and other potential field. Along with further growth and wider applications, the development of stack construction and configuration are also become a concern. In this paper, the principle of EDI process is described and its recent developments, commercial scale, and various applications are pointed out.

• Nuclear industry
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• v.30 no.3
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• pp.52-56
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• 2010

증기발생기 2차측 상태는 발전소 운영에 있어 중요한 역할을 수행한다. 기기, 배관 및 열교환기에서 발생되는 침적물은 증기발생기 튜브의 부식 원인이 될 수 있으며, 튜브와 튜브 지지판 사이의 공간을 차단한다. 2차측 침적물에 의한 튜브 파손으로 인해 일부 발전소에서는 강제적으로 발전을 정지하는 사례가 발생하였다. 또한 튜브 지지판의 침적물 축적으로 인해 정상 운전 동안 전력 생산을 감소하게 되는 결과를 초래한 발전소도 있었다. 따라서 증기발생기 2차측 상태 감시와 더불어 증기발생기 부품의 청결 유지는 필수 항목이라 할 수 있다. 웨스팅하우스에서는 증기발생기를 초기 제작 상태로 복구하고 2차측 침적물을 제거하기 위해 EPRI SGOG 증기발생기 화학 세정을 수 년간 이용하고 있다. 본고는 35개 이상의 발전소에서 성공적으로 이용하고 있는 화학 세정 프로세스 개요 및 프로세스를 적용하면서 취득한 경험을 요약한 것이다.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.04a
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• pp.89-93
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• 1998

In order to enlarge effection use as well as to use as a cheafut raw material for high-strength concrete admixture, we manufactured high strength admixture by using various industrial by-products and then applied to 2nd concrete pro when concrete was added MSS, strength of concrete was promoted and had a excellent property than domestic D admixture. This result could be explained that adding of MSS accelerated the famat of ettringite($C_3A$, $3CaSO_4$, $32H_2O$) like needle crystal in steam curing a also promoted to cement solidification and shorten high pre-strength display. As a result of, strength of concrete added MSS pretented, above 850kgf/$\textrm{cm}^2$ in 7 days of long-period curing.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.4 no.2
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• pp.65-71
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• 1992

In most absorption machines, absorption enhancement has been achieved by adding small amount of surfactant additive, which introduced the surface tension difference between absorbent and surfactant droplets in the vapor absorption. The aim of this study is to understand a basic mechanism of Marangoni convection and its effectiveness in the vapor absorption enhancement. In this study, nonflowing aqueous solution of LiBr 60 mass% was exposed to saturated water vapor under the condition that two dropwises surfactant were fixed on the absorbent surface. Our experiments achieved to visualize the enhanced heat and mass transfer phenomena by the effect of Marangoni convection through the laser holographic interferometry. Also, Marangoni convection behavior was obtained by using tracer method.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05b
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• pp.61-66
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• 1996

High pressure. high temperature steam/water blowdown test loop has been constructed. The loop simulates a pressurizer. depressurizalion system and In-Containment Refueling Water Storage Tank (IRWST) with full pressure and temperature conditions. and will be used to generate data for development of an optimal sparser as well as for design of safety/automatic depressurization system. In addition. experiments for reactor safety and pressurizer thermal hydraulics are scheduled. In this paper. general description of the Blowdown and Condensation (B&C) Loop will be given together with the test program.

• Journal of Environmental Health Sciences
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• v.14 no.2
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• pp.65-71
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• 1988

In this study, the method of adsorption by activated carbon in the removal of Hg(II) ion in waste water was treated. The influence of kinds of activated carbon and effect of temperature and the influence of coexistent salt on adsorption rates, the influence of pH in the adsorption, equilibrium and adsorption of mercury from activated carbon were investigated. From the adsorption on activated carbon of mercury(II) ion in the presence of cyanide or thiocyanate ion was found that mercury(II) was easily adsorved onto the activated carbon in the form of complex artion such as Hg(CN)$_4^{2-}$, Hg(SCN)$_4^{2-}$ respectively. ZnCl$_2$ activation method had a higher adsorptive ability than steam activation method in adsorption of Hg on activated carbon. Activated carbon adsorbed iodide ion is very effective on adsorption of Hg.