• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.609-613
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• 2003

The confinement of a storage system to accommodate spent fuel and radioactive material must be designed and estimated so that the storage system is safe during a storage period. The confinement can be estimated by calculation of the allowable leakage rate in compliance with ANSI Nl4.5 or ISO 12807. Accordingly, the allowable leakage rate was estimated in compliance with ISO 12807 in the case of storage of 24 PWR spent fuels and 24-conditioned spent fuels. In the case of the 24 PWR spent fuel assemblies, the allowable leakage rate was estimated as $7.43{\times}10_{-11}m_3/s$, in the case of the 24 conditioned spent fuel assemblies, the allowable leakage rate was estimated as $1.80{\times}10_{-10}m_3/s$. Therefore, the confinement condition in the storage of the conditioned spent fuel is easier than that for the storage of the PWR spent fuel.

• The Optical Journal
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• v.12 no.5 s.69
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• pp.47-53
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• 2000

1998년 일본 내 생산실적은 5조 6,342억엔, 1999년 일본 내 생산실적 6조 4,191억엔으로 성장률 저하 경향이 1998년 경계로 상승 무드로 전환됐다. 인터넷의 폭발적인 신장에 따른 디스플레이 소자의 증산 및 대 화면 제품의 시장 진출, 광전송기기 장치 등의 신장이 크게 기여했다. 2000년은 $17.1\%$ 성장한 7조 5,170억엔이 예측된다.

• 해운
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• s.95
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• pp.17-25
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• 2012

세계경제 둔화에도 국제유가가 상승세로 전환되었다. 국제유가는 2012년 1/4분기에 이란 사태로 인해 급등했다가 2012년 2/4분기에는 유로존 위기 등으로 급락했던 국제유가가 하반기에 들어 상승세로 전환되었다. 그러나 세계경제의 부진이 지속되면서 실물수요 측면의 유가 상승압력은 낮은 수준을 유지한다. IMF 등 주요 기관은 유로존 위기 등으로 세계경제의 회복세가 약화되자 2012년과 2013년 세계경제의 성장률을 하향 조정했다. 특히, 금융위기 발생 이후 세계경제의 버팀목이 되던 신흥국 경제의 성장 둔화가 본격화 되면서 석유 등 실물 수요도 둔화되었다. 2012년 3/4분기 중국의 성장률은 7.4%로 7분기 연속 하락했으며, IMF와 Global Insight는 2012년 중구그이 경제성장률을 각각 7.8%, 7.4%로 전망했다. 다음은 삼성경제연구소가 발표한 "2013 국제유가의 향방"의 주요 내용을 요약 정리한 것이다.

• Journal of Adhesion and Interface
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• v.4 no.3
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• pp.14-20
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• 2003

In order to study the radiation curing behavior of poly(ethylene glycol 400) dimethacrylate and ethylene glycol dimethacrylate, we investigated the influence of temperature and photoinitiator concentration by photo-DSC. As the number of ethylene glycol unit, the concentration of photoinitiator, and the reaction temperature increased, the reaction speed of PEG400DMA and EGDMA increased. Although the reaction speed of PEG400DMA was lower than EGDMA, the overall conversion of PEG400DMA was high.

• Journal of Digital Convergence
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• v.12 no.10
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• pp.121-134
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• 2014

This study investigated the stock market reaction to the announcement of conversion to holding company and its influence on the market value and corporate governance before and after the event. Generally, it is known that the conversion to holding company strengthens corporate governance because of diversification effects. Accordingly, it is expected that holding companies have a significantly positive influence on the short and long term stock value and improve firm performance. The results are as follows. First, companies have significantly positive short-term abnormal returns for a day. It confirms the stock market reaction hypothesis. Second, it is found that corporate governance is improved in two ways, protection of stock holders' right and distribution of corporate income in the year after converting to holding companies. However, the degree of business concentration appears to be decreased but the result is statistically insignificant after the conversion. Third, there is no significant positive relation between market performance and both protection of stock holders' right and distribution of corporate income. Thus, the results do not adequately support the hypothesis between corporate transparency and market performance.

• Applied Chemistry for Engineering
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• v.5 no.3
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• pp.385-394
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• 1994

Numerical solutions were obtained to the model equations for various of the parameters characterizing the pore structure, effective internal diffusion, and the chemical reaction constant. The conversion was decreased with the cause of pore closure at the surface of reacting particles, reduction of porosity, surface area of reaction and effective diffusion coefficient in the solid with the progress of reaction. Total conversion was strongly dependent on the local conversion at surface. According to the decreasing of impregnated concentration of the copper oxide and the increase of the flue gases concentration, total conversion was increased. The conversion was affected by gas flow rate and pore size distribution in the reacting solid.

• Applied Chemistry for Engineering
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• v.16 no.5
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• pp.672-676
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• 2005

To improve the application of polymeric dental restorative composite (PDRC) for the posterior and anterior restoration, silica bridged with siloxane unit was firstly prepared by heat-treating a silica filler at various temperatures. Degree of conversion (DC), depth of cure, and dynamic volumetric polymerization shrinkage values of PDRC filled with silica bridged with siloxane unit were investigated to study the effect of heat-treated silica on the polymerization behavior of PDRC. From the experimental result, it was found that depth of cure was decreased with an increase of heat treatment temperature. on the other hand, both DC and polymerization shrinkage values were uniformly enhanced with increasing the heat treatment temperature. This phenomenon can be explained from the study that showed decrease of average particle size of silica resulted in the increase of relative amount of resin matrix in PDRC.

• Proceedings of the Korea Information Processing Society Conference
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• 2008.11a
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• pp.145-148
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• 2008

장면 전환 검출은 대용량 비디오 데이터의 효과적인 관리를 위해서 사용되는 기술로서 현재까지 비디오 프레임의 크기를 대폭 축소시킨 환경에서의 연구는 미미하다. 따라서 본 논문에서는 비디오 프레임의 최소 화소를 이용한 장면 전환 검출 기술을 제안한다. 장면 전환 검출을 위한 특징값 추출 요소로 가중치 분산을 사용하였고, 가변 구간 참조를 통한 적응적인 임계값을 설정하였다. 실험을 통해서 기존의 방법들보다 precision에서 2~20.4%, recall에서 3~18.2%, F1에서 1.1~19.3% 향상된 것을 확인하였고, 비디오 데이터 화소수를 1/256로 축소하여 실험한 결과 기존의 방법들보다 검출률이 월등하게 향상된 것을 알 수 있었다. 제안하는 방법은 계산량 감소를 통한 고속 처리를 가능하게 하여 다양한 소프트웨어 및 하드웨어 플랫폼에서의 고속 장면 전환 검출에 유용하게 사용될 수 있다.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.40 no.11
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• pp.745-753
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• 2016

Micro methanol-steam reformer for fuel cell can effectively produce hydrogen as reforming response to steam takes place in low temperature (less than $250^{\circ}C$). This study conducted numerical research on this reformer. First, study set wall temperature of the reformer at 100, 140, 180 and $220^{\circ}C$ while methanol conversion efficiency was set in 0, 0.072, 3.83 and 46.51% respectively. Then, porosity of catalyst was set in 0.1, 0.35, 0.6 and 0.85 and although there was no significant difference in methanol conversion efficiency, values of pressure drop were 4645.97, 59.50, 5.12 and 0.45 kPa respectively. This study verified that methanol-steam reformer rarely responds under the temperature of $180^{\circ}C$ and porosity does not have much effect on methanol conversion efficiency if the fluid flowing through reformer lowers activation energy by sufficiently contacting reformer.

• Journal of Plant Biotechnology
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• v.30 no.1
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• pp.27-33
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• 2003

The optimal condition of in vitro regeneration and transformation were investigated for newly bred potato varieties in Korea. Leaf and internodal stem tissues of 'Chubak', 'Namsuh', 'Jasim', 'Jopung' and 'Jowon' were used to investigate the influence of growth regulator on regeneration efficiency The effect of phenolic compound acetosyringone on gene transformation efficiency was also investigated. Leaf tissue of 'Jowon' and internodal stem tissues of 'Jopung' were showed high regeneration efficiency on M5 medium supplemented with 0.1 mg/L GA₃, 2.0 mg/L Zeatin and 0.01 mg/L NAA. The other three potato cultivars were showed low regeneration efficiency less than 25%. The effect of acetosyringone on Agrobacterium-mediated gene transformation with leaf and internodal stem tissues were noticeable. By adding the 75 μM of acetosyringone during the Agrobacterium innoculation, the transformation efficiency was increased up to 1.5∼4.0 fold compare to non-treated control. In case of 'Jowon' the transformation efficiency was 87.9% in leaf tissue and 'Jopung' was 68.4% in internodal stem tissues.