• 한국세라믹학회지
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• 제43권5호
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• pp.270-276
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• 2006

LSGM(($La_xSr_{1-x})(Ga_yMg_{1-y})O_3$) electrolyte is known to show very serious interfacial reaction with other unit cell components, especially with an anode. Such an interfacial reaction induced the phase instability of constituent component and deterioration of the unit cell performance, which become the most challenging issues in LSGM-based SOFCs. In this study, we fabricated LSGM($La_{0.8}Sr_{0.2}Ga_{0.83}Mg_{0.17}O_x$) electrolyte supported-type cell in order to avoid such interfacial problem by lowering the heat-treatment temperature of the electrode fabrication. According to the microstructural and phase analysis, there was no serious interfacial reaction at both electrolyte/anode and electrolyte/cathode interfaces. Moreover, from the electrochemical characterization of the unit cell performance, there was no distinct deterioration of the open cell voltage as well as an internal cell resistance. These results demonstrate the most critical point to be concerned in LSGM-based SOFC is either to find a proper electrode material which will not give any interfacial reaction with LSGM electrolyte or to properly adjust the processing variables for unit cell fabrication, to reduce the interfacial reaction.

• 종양간호연구
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• 제9권1호
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• pp.31-42
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• 2009

Purpose: The purpose of the study was to understand how patients experience everyday life in an isolation unit for hematopoietic stem cell transplantation (HSCT). Method: The data were collected from 25 patients with HSCT at the isolation unit from January to March in 2008 in one general hospital in Korea. The data were collected by participant observations and ethnographic interviews and were analyzed using ethnographic method. Results: Four themes regarding environmental area emerged: 'barrier pulling up the drawbridge', 'very strange world', 'small and restricted space tied by IV and other treatment lines', and 'loud noise in a silent space.' Three themes regarding patients emerged: 'facing fear and anxiety', 'continuation of loneliness and lethargy', and 'compromising with a very long, dull, and boring time'. These themes describe how patients with HSCT suffer from continuous physical and psychosocial problems in a confined space, while endeavoring to control these problems and to search for hope for a new life. Conclusion: The results of the study provide an in-depth understanding of the experience and culture of patients in an isolation unit for HSCT. They would be used in developing practical programs to decrease patient's culture shock including fear and anxiety at isolation unit for HSCT.

• 식물조직배양학회지
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• 제25권5호
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• pp.289-293
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• 1998

다양한 유도조건에서 확립한 64종의 식물배양세포주의 MPA추출물을 대상으로 DPPH 라디칼을 이용하여 항산화 활성을 조사하고 활성이 높은 세포주를 대상으로 HPLC로 ascorbate 함량을 분석하였다. 13종의 세포주는 생체중 50mg 이하에서 DPPH 라디칼의 자연산화를 억제하는 높은 항산화활성을 나타내었다. 이중 6종의 세포주의 MPA추출물을 실리카겔 TLC에 전개하여 DPPH용액을 분무한 결과, ascorbate와 같은 Rf 위치에서 DPPH 양성반응을 나타내는 화합물이 존재하였다. DPPH 양성반응을 나타낸 덩굴장미(Rosa multiflora), 황금(Scutellaria baicalensis), 쇠무릎(Achyranthes japonica) 세포주의 ascorbate 함량($\mu\textrm{g}/g$ cell fresh wt)은 각각 48.5, 30.3, 16.8였다. 황금 캘러스 배양에서 ascorbate의 함량은 세포생장에 비례하여 정지기까지 증가한 후 계속적인 생장에 따라 급격히 감소하였다.

• Journal of Microbiology and Biotechnology
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• 제8권6호
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• pp.705-709
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• 1998

In the course of screening for the substances suppressing bleb formation of K562 cell induced by phorbol 12, 13-dibutyrate (PDBu), an inhibitor, chaetoglobosin A (CgA) was isolated from a cultured broth of unidentified fungus. CgA showed a strong inhibitory activity with the $IC_{50}$ value of 60 pM against bleb formation on K562 cells induced by PDBu, but it did not inhibit the activity of protein kinase C (PKC) in vitro. The inhibitory activity of CgA might be due to the modulation of actin filaments on the cell membrane. CgA exhibited strong cytotoxicity against various human cancer cell lines.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1031_1032
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• 2009

The voltages of unit cells of a fuel cell stack are one of the most significant factors to detect failure conditions and thereof safely control and operate the fuel cell system. In this paper, we describe two methods to monitor the voltages of the unit cells of a stack in consideration of data accuracy, circuit extensibility to various numbers of cells, and cost. The reported methods are approached by (i) the power isolation of cell voltage monitoring part from the communications part and (ii) the utilization of a commercially available cell monitoring integrated circuit IC of a Li-ion battery.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.299-302
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• 2009

Oxygen ionic conductors of YSZ electrolyte in SOFC unit cell are applied to anode and cathode as well as electrolyte to have triple-phase-boundaries(TPB) of electrochemical reaction, and it is required to decrease the sintering temperature of anode-supported electrolyte by the nanoscale of YSZ powder.In this report, nanoscale YSZ powder was synthesized by the chemical co-precipitation method. The particle size, surface area and morphology of the powder were observed by SEM and BET. Thin film electrolyte of under 10㎛ was fabricated by tape casting using the synthesized YSZ powder, and ionic conductivity and gas permiability of electrolyte film were evaluated. Finally, the SOFC unit cell was fabricated using the anode-supported electrolyte prepared by a tape casting method and co-sintering. Electrochemical evauations of the SOFC unit cell, including measurements such as power density and impedance, were performed and analyzed.

• 한국항해항만학회지
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• 제45권5호
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• pp.231-237
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• 2021

Enhancing the performance of maritime wireless communication has been highlighted by the issue of cell planning in the sea area because of lack of an appropriate Propagation Loss Model (PLM). To resolve the cell planning issue in vast sea areas, it was essential to develop the (PLM) matching the intended sea area. However, there were considerable gaps between the prediction of legacy PLMs and field measurement in propagation loss and there was a need to develop the adjusted PLM (A-PLM). Therefore, cell planning was performed on this adjusted model, including modification of the base station's location, altitude, and antenna azimuth to meet the quality objectives. Furthermore, in order to verify the availability of the cell planning, Communication Service Quality Monitoring System (CS-QMS) was developed in the LTE-Maritime project to collect LTE signal quality information from the onboard equipment at regular intervals and to ensure that the service quality was high enough to satisfy the goals in each designated grid. As a result of verification, the success rate of RSRP was 95.7% for the intensive management zone (IMZ) and 96.4% for the interested zone (IZ), respectively.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2005년도 춘계학술발표대회 논문집
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• pp.134-136
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• 2005

Homogenization method is adopted to predict the permeability tenor for glass fiber plain woven fabrics. Calculating the permeability tensor numerically is an encouraging task because the permeability tensor is a key parameter in resin transfer molding (RTM). Based on multi-scale approach of the homogenization method, the permeability for the micro-unit cell within fiber tow is computed and compared with that obtained from flow analysis for the same micro-unit cell. It is found that they are in good agreement. In order to calculate the permeability tensor of macro-unit cell for the plain woven fabrics, the Stokes and Brinkman equations which describe inter-tow and intra-tow flow respectively are employed as governing equations. The effective permeabilities homogenized by considering intra-tow flow are compared with those obtained experimentally. Control volume finite element method (CVFEM) is used as a numerical method. It is shown that the asymptotic expansion homogenization method is an attractive method to predict the effective permeability for heterogeneous media.

• 대한전기학회논문지:시스템및제어부문D
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• 제54권8호
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• pp.486-494
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• 2005

This paper presents a design experience of a supervisory control system. For effective programming of job commands, a petri net-type graphical language (PGL) is proposed applied to various tasks having concurrency and synchronization. Our PGL based supervisory control system is composed of PGL editor and PGL compiler; PGL editor is designed to help us to generate a job program using graphical symbols. PGL compiler includes analyzer, scheduler, and tranlator, PGL analyzer prevents a deadlock or resource allocation of unit cell, PGL scheduler generates a adequate job sequence of unit cell. and PGL translator translate the scheduled sequence into the iob program of each unit cell.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 2000년도 춘계공동학술대회 논문집
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• pp.1-4
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• 2000

In general, under the concept of unit load, Automated Storage/Retrieval Systems (AS/RS) have the rack of equal sized cells. However, they are inadequate and inefficient meeting the various sizes of customers' demands in today's business environment. Higher utilization and flexibility of warehouse storage can be achieved by using AS/RS with tile rack of modularized cell. In this paper, the model of AS/RS with the rack of modularized cell is proposed, and the effectiveness of proposed model is presented by way of numerical examples. The model developed in this research, as one type of AS/RS that is more flexible to the size and has higher space utilization than those of existing rack structure, could every useful for the storage of heterogeneous unit load sizes.