• Journal of the Korean Ceramic Society
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• v.24 no.2
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• pp.123-132
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• 1987

Yttria-stabilized zirconia with erbia-lanthana were investigated with respect to the amount of Ln2O3 (Ln; Er, La) addition in the range of 0.5∼5 mol% to the base composition of 8 mol% yttriazirconia. Following analysis and measurement were adopted for the characterization of synthesizes of solid electrolyte; phase transformation, lattice parameter, crystallite size, relative density, chemical composition and SEM/EDS. Electrical conductivity by two-probe method versus temperature from 350$^{\circ}C$ to 800$^{\circ}C$ and frequency in the range of 5Hz∼13MHz by complex impedance method was also conducted together with the determination of oxygen ion transference number by EMF method for the evaluation of their electrical properties. The results were as followsing; Electrical conductivity were decreased with increase in Ln2O3 content, but their activation energies increased. In the case of La2O3 addition, espicially, its electrical conductivity was decreased owing to the segregation of second phases at the grain-boundary. Grain-boundary conductivity of the specimen contained 0.5 mol% Er2O3 exhibited a maximum conductivity among thecompositions experimented. However, their bulk conductivities decreased in both case. Oxygen ion transference number was also reduced with decrease in oxygen partial pressure. For example, in the case of Er2O3 addition it retained value in the range of 0.97∼0.94 abvove 4.74${\times}$10-2in oxygen partial pressure. With the increase in the quantities of the evaporation of additive components, the crystallite size of stabilized zirconia decreased, and their relative density also reduced owing to the formation of porosity in their matrices. In the case of La2O3 the sinterbility was improved in the limited amount of addition up to 0.5 mol%, in the same range of addition the strength of sintered bodies were improved perhaps owing to the precipitation of metastable tetragonal phase in the fully stabilized zirconia.

• Journal of the Korean Ceramic Society
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• v.36 no.1
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• pp.69-76
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• 1999

Electrical characteristics of perovskite phases in the BaCe0.9R0.1O3-$\delta$(R=La, Yb and Al) system have been studied. Electrical conductivities of all specimens in air were higher than those in N2 atmosphers between 600 and 100$0^{\circ}C$. When temperature was elevated, the electrical conductivity difference between both atmospheres increased. Electrical conductivity of Yb3+ doped BaCeO3 specimen was higher than those of the La3+ and Al3+ doped specimens. The BaCe0.0Al0.1O3-$\delta$ showed higher proton transference number than both BaCe0.9Yb0.1O3-$\delta$ and BaCe0.9La0.1O3-$\delta$.

• Journal of Digital Convergence
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• v.20 no.4
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• pp.519-528
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• 2022

The purpose of the study was to further investigate the direction for one-person experience design based on visual shift due to the isolation one has experienced after the COVID-19 and the factors regarding it. The study involves eight female participants who are in their twenties via digital platform. The participants were instructed to choose digital image similar to COVID-19 and to write down facts based upon the image and the researcher will look into the result microscopically. The researchers found that the isolation factors include decreased face-to-face communication, reliance on social media, heavy usage of OTT platform, limited outdoor occasion and activity, limitation of untact technology and education program, fear over the pandemic and so on. The study has shown that the one-person experience design should be heading in a direction where it adopts space design that can crossover online and offline world, digital complex design to embody realness as well as the communication design to regain the relationships with others.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.365-368
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• 2002

This paper considers transference number in calculating diffusion coefficient of chloride ions of concrete and mercury intrusion porosimetry to investigate the volume and distribution of pore size, respectively, analyzing and discussing the property of resistance to chloride ion of concrete with granulated blast furnace slag. The experimental results show that the diffusion coefficient of chloride ion decreases with the rise of quantity of granulated blast furnace slag and pore structure of concrete with granulated blast furnace slag is different from that of OPC concrete. And from the results of regression analysis, the result showed that the diffusion coefficient of chloride ions is affected by capillary pore above 50nm.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.2
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• pp.297-305
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• 2003

The family of lemnacae colloquially known as duckweed contains the world' smallest species of flowering plants (macrophytes). Aquatic and free-floating, their most striking qualities are a capacity for explosive reproduction and an almost complete lack of fibrous material. They are widely used for reducing chemical loading in facultative sewage lagoons, but their greatest potential lies in their ability to produce large quantities of protein rich biomass, suitable for feeding to a wide range of animals, including fish, poultry and cattle. Despite these qualities there are numerous impediments to these plants being incorporated into western farming systems. Large genetically determined variations in growth in response to nutrients and climate, apparent anti-nutritional factors, concerns about sequestration of heavy metals and possible transference of pathogens raise questions about the safety and usefulness of these plants. A clear understanding of how to address and overcome these impediments needs to be developed before duckweed is widely accepted for nutrient reclamation and as a source of animal feed.

• The Journal of the Convergence on Culture Technology
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• v.4 no.2
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• pp.149-153
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• 2018

The purpose of this study is to actively utilize the type of tension of Sijo in literary therapy programs. I will examine the Sijo of the Bang-yeon Wang. The Sijo of the Bang-yeon Wang is not known much yet, so we will discuss it. The Sijo of the Bang-yeon Wang has the effect of conveying the meaning while the modifier tensions the next sentence. This literary framework can be useful for literary therapy programs.

• Knowledge Management Research
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• v.12 no.1
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• pp.111-121
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• 2011

Multinational Corporations (MNCs) are establishing globally-distributed R&D centers around the world. Firms can overcome resource constraints and achieve superior innovative performance not only by using internal resources but also acquiring knowledge from oversea R&D centers. This paper explores the key factors that have been cited as significant influences on the ability to transfer knowledge, an important area of knowledge management of MNCs. Also, we identify the emerging outcomes in terms of R&D transfer and for the education, employment, and retention of knowledge works in MNCs. The result will be helpful for both MNC's managers and governments' decision makers with respect to R&D centers.

• Journal of the Korean Institute of Landscape Architecture
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• v.19 no.2
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• pp.23-31
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• 1991

In this paper, based on the thought of the place, I tried to define the meaning of th place and interprete its landscape. The landscape of the mt. Toham with its Grotto-temple "Sokgulam" is the major object of it. The "matter and form" of the Sokgulam realizes the archetypal meaning of the grotto, birth or place of the birth, in a concrete picture. The aesthetics of the Sokgulam, the mater and form in the work of arts, comes out light harmonious with the elements: "grotto", the new foreign element of the architectural style and "orientation", the old domestic one of the Shilla that presented itself at the Chomsongdae, a kind of observatory. The interrelation of the old and new elements in work of the Sokgulam shows us also a thought as an opinion of the transference to say: the matter of the traditional subject, "grotto" and the form makes the abstract matter concretely in sight, by receiving the natural happening of the sunrise at the winter solstice.

• Proceedings of the KSME Conference
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• 2001.06c
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• pp.170-175
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• 2001

The design cycle associated with large engineering systems requires an initial decomposition of the complex system into design processes which are coupled through the transference of output data. Some of these design processes may be grouped into iterative subcycles. In analyzing or optimizing such a coupled system, it is essential to determine the best order of the processes within these subcycles to reduce design cycle time and cost. This is accomplished by decomposing large multidisciplinary problems into several multidisciplinary analysis subsystems (MDASS) and processing it in parallel. This paper proposes new strategy for parallel decomposition of multidisciplinary problems to improve design efficiency by using the multiple objective genetic algorithm (MOGA), and a sample test case is presented to show the effects of optimizing the sequence with MOGA.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.174-179
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• 2004

The paper deals with gravitational effect on dynamic stability of a cantilevered pipe conveying fluid. The eigenvalue branches and modes associated with flutter of cantilevered pipes conveying fluid are fully investigated. Governing equations of motion are derived by extended Hamilton's principle, and the solutions are sought by Galerkin's method. Root locus diagrams are plotted for different values of mass ratio of the pipe, and the order of branch in root locus diagrams is defined. The flutter modes of the pipe at the critical flow velocities are drawn at every one of the twelfth period. The transference of flutter-type instability from one eigenvalue branches to another is investigated thoroughly.