• Journal of the Korean Ceramic Society
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• v.27 no.1
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• pp.91-101
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• 1990

The green microstructure and sintering behavior of ZrO2 were analyzed in terms of kinetic stability (measured by the stability ratio ; W) and interfacial characteristics of colloidal suspension. Green density and the most frequent pore radius(MFPR) of green body were directly correlated with the stability ratio. These observations were explained using a concept of the critical stability ratio(Wc) and the potential energy of two interacting particles in colloidal suspension. Analysis of the data also indicates that the potential energy barrier between two interacting colloid particles should be higher than its critical value for a fabrication of ZrO2 green body with dense and uniform microstructure. Besides, we have successfully applied a concept of the donoracceptor interaction to increase the kinetic stability of ZrO2 slip and density of green body.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.1701-1706
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• 2004

FRT design aims at high-tech vehicles of high efficiency and cleanness, it must materialize the meaning and role as new added value by applying car design aesthetics of a new future-oriented concept. In addition, different from ordinary vehicle design, FRT involves invisible factors such as pleasantness, safety, accessibility, controllability, movability, conveniency, culture, identity, brand image and fashionableness. Because FRT vehicles are transportation means used by various groups of people, they must be approached with the barrier-free design concept. Therefore, in order to enhance the potential of future transportation culture emphasizing creativity based on diversity, it is important to establish core design factors that create new added values and to apply new concepts to their roles.

• Nuclear Engineering and Technology
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• v.43 no.2
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• pp.105-132
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• 2011

The concept of improved performance indicators (PIs) for use in the KINS Safety Performance Indicator (SPI) program for reactor safety area is proposed in this paper. To achieve this, the recently developed PIs from the USNRC that use risk information were investigated, and a feasibility study for the application of these PIs in Korean NPPs was performed. The investigated PIs are Baseline Risk Index for Initiating Events (BRIIE), Unplanned Scrams with Complications (USwC), and Mitigating System Performance Index (MSPI). Moreover, the thresholds of the existing safety performance indicators of KINS were evaluated in consideration of the risk and regulatory response to different levels of licensee performance in the graded inspection program.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.11 no.2
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• pp.157-178
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• 2013

This study gives a conceptual and basic direction to develop a URL (underground research laboratory) program for establishing the performance and safety of a deep geological disposal system in Korea. The concept of deep geological disposal is one of the preferred methodologies for the final disposal of spent nuclear fuel (SNF). Advanced countries with radioactive waste disposal have developed their own disposal concepts reasonable to their social and environmental conditions and applied to their commercial projects. Deep geological disposal system is a multi-barrier system generally consisting of an engineered barrier and natural barrier. A disposal facility and its host environment can be relied on a necessary containment and isolation over timescales envisaged as several to tens of thousands of years. A disposal system is not allowed in the commercial stage of the disposal program without a validation and demonstration of the performance and safety of the system. All issues confirming performance and safety of a disposal system include investigation, analysis, assessment, design, construction, operation and closure from planning to closure of the deep geological repository. Advanced countries perform RD&D (research, development & demonstration) programs to validate the performance and safety of a disposal system using a URL facility located at the preferred rock area within their own territories. The results and processes from the URL program contribute to construct technical criteria and guidelines for site selection as well as suitability and safety assessment of the final disposal site. Furthermore, the URL program also plays a decisive role in promoting scientific understanding of the deep geological disposal system for stakeholders, such as the public, regulator, and experts.

• Tunnel and Underground Space
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• v.7 no.1
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• pp.39-50
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• 1997

Reference concepts for the disposal of spent nuclear fuel and the current status of underground rock laboratory were studied. An analysis to simulate the deep disposal of spent nuclear fuel in saturated rock mass was conducted. Main input parameters for numerical study were determined based on the KBS-3 concept. A series of results showed that the temperature distribution around a cavern reached the maximum value at about 10 years after the emplacement of spent fuel. The maximum temperature at the surface of canister was more than about 12$0^{\circ}C$ at about 4 years. This temperature was not much higher than the temperature criteria to meet the performance criteria of an artificial barrier in the KBS-3 concept. The maximum upward displacement due to the heat generation of spent fuel was about 0.9cm at about 10 years after the emplacement of spent fuel. It turned out that the vertical displacement became smaller with the decrease in heat generation of a canister. The quantity of groundwater inflow into a disposal tunnel increased by about 1.6 times at 20 years after the emplacement of spent fuel with the increase of pore pressure around a cavern.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.15 no.4
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• pp.301-312
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• 2017

The concept of deep borehole disposal (DBD) for high-level nuclear wastes has been around for about 40 years. Now, the Department of Energy (DOE) in the United States (U.S.) is re-examining this concept through recent studies at Sandia National Laboratory and a field test. With DBD, nuclear waste will be emplaced in boreholes at depths of 3 to 5 km in crystalline basement rocks. Thinking is that these settings will provide nearly intact rock and fluid density stratification, which together should act as a robust geologic barrier, requiring only minimal performance from the engineered components. The Nuclear Waste Technical Review Board (NWTRB) has raised concerns that the deep subsurface is more complicated, leading to science, engineering, and safety issues. However, given time and resources, DBD will evolve substantially in the ability to drill deep holes and make measurements there. A leap forward in technology for drilling could lead to other exciting geological applications. Possible innovations might include deep robotic mining, deep energy production, or crustal sequestration of $CO_2$, and new ideas for nuclear waste disposal. Novel technologies could be explored by Korean geologists through simple proof-of-concept experiments and technology demonstrations.

• Journal of Families and Better Life
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• v.32 no.3
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• pp.85-97
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• 2014

This study attempted to explore parents'perceptions on character and character education for their children using a focus group interview method. According to previous research, the concept of character consists of wholeness of three components: relationship, individuality, and morality. This study investigated how parents' perception differ from the widely agreed concept of character. Forty-four mothers and ten fathers participated in eleven focus group interviews. The results showed that parents recognized social relationship and self realization as two most important components of character education of children. However, the parents paid less attention on morality and wholeness. The parents conceptualized character as an alternative to academic achievement. For example, they considered self realization as an alternative to academic achievement. These tendencies could be a barrier in character education in family. Based on these findings, this study recommends that parent education should take more attention on character education in family and help parents develop a balanced understanding on the concept of character.

• Journal of the Society of Naval Architects of Korea
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• v.56 no.3
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• pp.251-262
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• 2019

This paper is about design concept and simplified analysis method against dropped object events. The ships and offshore structures are exposed to various types of dropped object accidents such as laydown area struck by drill collar and topside deck hit by food container during their lifetime. Mitigation can be accomplished by proper facility layout and designing structures to safely absorb energy from accidental loads. It shall be designed to avoid loss of life, environmental pollution and loss of assets. Impact loads can lead to structural global collapse of the main structure or punching of a local barrier type structure with potential to escalate directly or indirectly to a global collapse of the structure. This study provides the background information on the issue of dropped object of the shipyard and also focuses on structural assessment of the local individual component such as deck plate, stiffener and web/girder by using simplified analysis method. The results of the simplified analysis method were compared with numerical results using non-linear finite element simulation.

• Journal of Korean Academy of Nursing
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• v.31 no.1
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• pp.126-138
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• 2001

The purpose of this study is to act nursing intervention strategies to promote quality of life (QOL) in Spinal Cord Injury patients. Therefore, the study is designed to evaluate religion, marital status, educational background economic status, level of injury, voiding pattern, transportation by driving, rehabilitation education, self-concept, sexual status, perceived barrier, powerlessness, depression, hope, social support, self-efficacy, anxiety, ADL, perceived hopelessness, personality and pain for QOL at the same time. It was gathered empirical data was collected using a self report questionnaire from 61 patients during a six month period after SCI at 5 general hospitals, at 2 rehabilitation centers and at 2 rehabilitation schools province from Jun. 18, 1999 through Sep. 28, 1999. The reliability of the 19 instruments was tested with Cronbach's alpha which ranged from .6319 to .9769. For the data analysis a SAS program was used for Pearson correlation coefficients, and stepwise multiple regression. The results were as follows; 1. The mean of total item score in the QOL scale was 2.814, which showed a much lower score than the cancer points. 2. There was a significant correlation between self concept, transportation by driving, perceived barrier, powerlessness, depression, hope, social support, self-efficacy, anxiety, ADL and QOL.(${\gamma}$= .27~-.79, p< .05) 3. Stepwise multiple regression analysis showed that; a) Depression was the main predictor of QOL and account for 53.7% of the variance in QOL. b) Hope, ecomic status and body satisfaction accounted for 8%, 4%, 3.4% respectively and these variables combined accounted for 69.2% of the variance in QOL. In conclusion, to begin with, it is important to reduce depression and to help for SCI points to inspire hope, economic status and body satisfaction. That will be short cut for nursing strategies to enhance QOL.

• Transactions of the Korean hydrogen and new energy society
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• v.12 no.4
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• pp.257-265
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• 2001

Placing a hydrogen conducting, methanol impermeable metallic barrier like palladium (Pd) is a well-known method for preventing methanol crossover through solid polymer electrolyte for direct methanol fuel cells (DMFC). Applying a bias potential between the anode and the barrier can further develop this concept so that the hydrogen transfer rate is enhanced. Since hydrogen diffuses in Pd as atomic form while it moves through nafion electrolyte as ion, it has to be reduced or oxidized whenever it passes the interface formed by Pd and the electrolyte. We performed experiments to measure the hydrogen transport through the Pd membrane placed in Nafion electrolyte of hydrogen/oxygen fuel cell (PEMFC). Applying a bias potential between the hydrogen electrode of the cell and the Pd membrane facilitated the hydrogen passage through the Pd membrane. The results show that the cell current measured with the Pd membrane placed reached almost 40 % the value measured with the cell without Pd membrane. It was found that the current flown through the bias path is only a few percent of the cell current.