• 한국세라믹학회지
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• 제24권2호
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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.

• 한국세라믹학회지
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• 제36권1호
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• pp.69-76
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• 1999

BaCeO3 페롭스카이트 구조의 Ce4+ 자리에 3가의 양이온 (La3+, Yb3+, Al3+)을 10 mol% 첨가하여 열처리한 후 전기적 특성을 관찰하였다. 전기전도도 측정 결과 모든 조성에서 질소분위기에서 측정한 경우보다 대기 중에서 측정한 경우의 전기전도도가 높게 측정되었으며 이러한 경향은 온도가 높아질수록 두드러졌다. 전기전도도는 BaCe0.9Yb0.1O3-$\delta$조성에서 가장 높았고 BaCe0.9Al0.9O3-$\delta$ 조성에서 가장 낮았다. proton의 수송율(transference number)을 기전력 측정법을 통해 비교한 결과 Al을 첨가한 조성에서 모든 온도에 걸쳐 가장 높은 proton의 수송율을 얻을 수 있었다.

• 디지털융복합연구
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• 제20권4호
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• pp.519-528
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• 2022

연구 목적은 COVID-19 사태 이후 1인이 경험한 고립 요인을 시각적 전이에 기초한 내러티브 방법으로 살펴, 1인 경험의 디자인 방향을 탐구하는 데 있다. 연구 범위는 비대면 디지털 플랫폼을 통해 참여한 20대 여성 8명의 COVID-19 경험이다. 연구 방법은 참여자가 COVID-19 상황과 유사한 디지털 이미지를 선택하여 이에 근거한 경험 사실을 기술하면, 이를 연구자가 미시적으로 분석한 것으로 한정한다. 분석 결과, 고립 요인은 대면 소통의 부족, SNS 의존, OTT 서비스 중독, 외부 장소 이용 및 활동 한정, 비대면 기술의 한계, 비대면 교육 효과의 한계, 감염병 우려 등으로 요약되었다. 그러므로 고립 극복 요소에 근거한 1인 경험 디자인 방향은 관계 회복을 위한 커뮤니케이션, 온·오프라인 통합의 비 경계 장소, 현존감 구현을 위한 디지털 융·복합 콘텐츠 등이 전제되어야 할 것으로 예측된다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 가을 학술발표회 논문집
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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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• 제16권2호
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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.

• 문화기술의 융합
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• 제4권2호
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• pp.149-153
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• 2018

본 연구의 목적은 시조의 긴장의 유형을 문학치료 프로그램에 적극적으로 활용하기 위한 것이다. 왕방연의 시조를 대상으로 살펴보고자 한다. 왕방연의 시조는 잘 알려지지 않고 있어 논의해 보기로 하는 것이다. 왕방연의 시조는 수식어가 다음 문장에 긴장을 일으키며 의미를 전달하는 효과를 지니고 있다. 이러한 문학적 틀은 문학치료의 프로그램에 유용하게 사용될 수 있을 것으로 사료된다.

• 지식경영연구
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• 제12권1호
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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.

• 한국조경학회지
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• 제19권2호
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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.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집C
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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.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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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.