• Journal of the Korean Ceramic Society
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• v.44 no.8
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• pp.424-429
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• 2007

Novel conductive $CO_2$ membranes composed of dual phases, molten carbonates and electronic conducting ceramics, were investigated. As the microstructure control of electronic conducting ceramic supports is extremely important to keep the molten carbonates stable in the membranes by a capillary force applied by the pore structure of the supports, we have scrutinized the microstructure of the electronic conducting supports utilizing microscopic images and gas permeability measurement. From the evaluation of the electrical conductivities of the molten carbonates and the electronic conducting ceramic supports, we found that the ionic conductivity of the molten carbonates could determine $CO_2$ flux through the dual phase membranes if the surface exchange rate were relatively high enough.

• Nuclear Engineering and Technology
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• v.43 no.5
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• pp.447-458
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• 2011

This paper proposes an approximated contact force model to identify the nonlinear behavior of a fuel rod with gap supports; also, the numerical prediction of interfacial forces in the mechanical contact of fuel rods with gap supports is studied. The Newmark integration method requires the current status of the contact force, but the contact force is not given a priori. Taylor's expansion can be used to predict the unknown contact force; therefore, it should be guaranteed that the first derivative of the contact force is continuous. This work proposes a continuous and differentiable contact force model with the ability to estimate the current state of the contact force. An approximated convex and differentiable potential function for the contact force is described, and a variational formulation is also provided. A numerical example that considers the particularly stiff supports has been studied, and a fuel rod with hardening supports was also examined for a realistic simulation. An approximated proper solution can be obtained using the results, and abrupt changes from the contacting state to non-contacting state, or vice versa, can be relieved. It can also be seen that not only the external force but also the developed contact force affects the response.

• Transactions of the Korean hydrogen and new energy society
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• v.21 no.3
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• pp.214-219
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• 2010

In this study, we fabricated tubular ceramic support for segmented-in-series solid oxide fuel cell (SOFC) by using CSZ(CaO-stabilized $ZrO_2$) as main material and activated carbon as pore former. Thermal expansion properties of ceramic support with different amounts of activated carbon were analyzed by using dilatometer to decide a suitable sintering temperature. The tubular ceramic supports with different amounts of activated carbon (5, 10, 15wt.%) were fabricated by the extrusion technique. After sintering at $1100^{\circ}C$ and $1400^{\circ}C$ for 5h., cross section and surface morphology of tubular ceramic support were analyzed by using SEM image. Also, the porosity, mechanical property, gas permeability of tubular ceramic supports was measured. Based on these results, we established the suitable fabrication technique of tubular ceramic support for segmented-in-series SOFC.

• Carbon letters
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• v.14 no.2
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• pp.121-125
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• 2013

In this study, PtRu nanoparticles deposited on binary carbon supports were developed for use in direct methanol fuel cells using carbon blacks (CBs) and multi-walled carbon nanotubes (MWCNTs). The particle sizes and morphological structures of the catalysts were analyzed using X-ray diffraction and transmission electron microscopy, and the PtRu loading content was determined using an inductively coupled plasma-mass spectrometer. The electrocatalytic characteristics for methanol oxidation were evaluated by means of cyclic voltammetry with 1 M $CH_3OH$ in a 0.5 M $H_2SO_4$ solution as the electrolyte. The PtRu particle sizes and the loading level were found to be dependent on the mixing ratio of the two carbon materials. The electroactivity of the catalysts increased with an increasing MWCNT content, reaching a maximum at 30% MWCNTs, and subsequently decreased. This was attributed to the introduction of MWCNTs as a secondary support, which provided a highly accessible surface area and caused morphological changes in the carbon supports. Consequently, the PtRu nanoparticles deposited on the binary support exhibited better performance than those deposited on the single support, and the best performance was obtained when the mass ratio of CBs to MWCNTs was 70:30.

• Journal of Engineering Education Research
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• v.16 no.6
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• pp.29-37
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• 2013

The necessity of convergence education is more emphasized based on the education policy for fostering creative men of talent. Inside universities, however, programs for training talented individuals are still at primary stage. Universities understanding the importance of convergence education and thus founding some major fields of convergence studies have experienced hosts of troubles. The paper discusses the necessary plans of supports from the government and the university to activate the convergence education in accord with the social demands. Twenty-eight professors in engineering colleges participated in the survey for reviewing the required factors for the convergence education. In addition, structured interviews were carried out with three specialists working in industry and academic area of convergence technology. The study could suggest the following activation plans based on the government supports: (1) establishing a support center of convergence education, (2) founding a major field of convergence, (3) developing curriculums and curriculum subjects, and (4) hosting related conferences and forums. Also, the study could suggest the following activation plans based on the university supports: (1) developing special programs on convergence education in accord with the industrial demands, (2) revising regulations and administrative systems more flexible for the convergence education, and (3) providing incentives to the participants in the convergence education.

• Korean Journal of Child Studies
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• v.28 no.5
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• pp.221-232
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• 2007

The purpose of this study was to investigate the relationship among personal attributions of daycare center teachers in fields, social support, and teachers' burn-out. Data were collected by 228 teachers in day care center. To examine the relationship among personal attributions of daycare center teachers in fields, social support, and teachers' burn-out, it was used the scale of 'the tendency of attributions', 'social supports', and 'burn-out'. To analyze data, Pearsons' correlation and multiple regression were used. The results of this study were as followed. First, the score of daycare center teachers' personal attributions, social support, and teachers' burn-out were higher than the mean score. Second, internal and external variables were related to burn-out factors. Third, attribute disposition were related to teachers' burn-out. As a whole, teachers were tend to be in internal attributions, which led to a tendency to show positive reactions against burn-out. Forth, social supports were related to teachers' burn-out.

• Korean Institute of Interior Design Journal
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• v.27 no.2
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• pp.106-117
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• 2018

The purpose of the study is to present the social welfare center planning factors of space for promoting intergenerational exchanges between the elderly and children. To achieve the purpose, the study conducted a survey of professionals on the importance of planning factors. The results are as follows. First, it is surveyed that less high are Korean social welfare center planning and availability extents of space for intergenerational exchanges, while less no profound are the necessity and concern of such spaces. The result suggests that social welfare centers need a concrete planning of space for intergenerational exchanges. Second, it is identified that in order to promote intergenerational exchanges, there need to plan planning factors of each space, especially with focus on 'outdoor space' and 'specific space.' Third, it is revealed that regarding the importance of factors of 'specific space,' physical supports account for the high rates; architectural factors providing free space contribute to the supports of physical development; and decorative factors giving visual effects could be helpful for behaviors. Fourth, it is unveiled that the supports of physical behaviors are of the most importance in 'connecting space'. This would be planned as a path that gives a free access in spaces, with attention being paid to safety. Lastly, it is shown that in the case of 'outdoor space,' the supports of physical development are of the most importance. Given the fact that 'outdoor space' offers a wider scope of activities, and accommodates various available elements in connection with surrounding environments, it is considered that the space would be of help for intergenerational interactions. The study is expected to be utilized as the preliminary data which proposes the social welfare center planning factors of space for promoting intergenerational exchanges between the elderly and children.

• Journal of Ocean Engineering and Technology
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• v.10 no.1
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• pp.17-24
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• 1996

In the present paper nonlinear normal modes of a rotor system is studied. The methodology to obtain the nonlinear normal modes is based on center manifold reduction technique. It also provides a way of nonlinear coordinate transform from the physical cordinates to the modal coordinates and an idea of individual nonlinear modal dynamics. In order to apply the present method to a rotor dynamics a single mass rotor system on nonlinear elastic supports is employed and the nonlinear normal modes of the system are obtained.

• Proceedings of the KIEE Conference
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• 2006.11a
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• pp.111-113
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• 2006

Substation automation is one of the key issues for the enhancement of the power industrial foundation. IEC 60850 is an international standard specifying communication network and systems in substation. It supports interchangeability and interoperability of equipments from different vendors. ACSI(Abstract communication service interface) specifies basic communication structure for substation and IEDs. It supports communication as well as various services without proper protocols. For actual communication, MMS(Manufacturing Message Specification : ISO 9506) is used to map ACSI services. Solutions for the development of communication driver based don IEC 61850 are proposed in this paper.

• Journal of Family Resource Management and Policy Review
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• v.22 no.1
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• pp.79-98
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• 2018

The purpose of this study was to analyze the influence of a married adult on child-toparent and on parent-to-child financial supports. The data, derived from Korean General Social Survey(KGSS) was obtained from the Survey Research Center at Sung Kyun Kwan University. The samples included 367 married adult children who had more than one living parent. Multiple regression analysis was used to analyze the research model. The findings from the analysis showed that monthly household income had no significant impact on the financial supports that adult children provided to their parents or that the parents provided to their child. The expectation of financial supports from their parents in the future was a important factor that affected the level of female and male children's financial supports that they received from their parents. The level of instrumental supports from their parents and their parents-in-law did influence the level of financial transfers between them. These results showed that financial transfers between married adult children and their parents differed based on the children's attitude towards the supporting parents, and whether or not the children or parents had alternative resources available to them for financial supports. Moreover, the variation in financial supports and benefits showed complex differences based on the gender of the children, and based on whether the financial support was coming from the respondent's parents or their partner's parents.