• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.03a
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• pp.160-167
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• 2008

The effects of squealer rim height on three-dimensional flows and aerodynamic losses downstream of a high-turning turbine rotor blade have been investigated for a typical tip gap-to-chord ratio of h/c=2.0%. The squealer rim height-to-chord ratio is changed to be $h_{st}/c$=0.00(plane tip), 1.37, 2.75, 5.51, and 8.26%. Results show that as $h_{st}/c$ increases, the tip leakage vortex tends to be weakened and the interaction between the tip leakage vortex and the passage vortex becomes less severe. The squealer rim height plays an important role in the reduction of aerodynamic loss when $h_{st}/c{\leq}2.75%$. In the case of $h_{st}/c{\geq}5.51%$, higher squealer rim cannot provide an effective reduction in aerodynamic loss. The aerodynamic loss reduction by increasing $h_{st}/c$ is limited only to the near-tip region within a quarter of the span from the casing wall.

• Journal of the Korean Regional Science Association
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• v.35 no.3
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• pp.7-23
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• 2019

Smart cities are expanding their spatial scope to urban areas and regions. Linking regional economic development strategies beyond the borders with smart city planning can lead to cooperation and economic development between regions and countries as well. The purpose of this study is to suggest cooperation and regional development of the three nations - Korea, North Korea and China - through the Yellow Sea Rim Smart Region. To this end, smart city strategies and economic development plan with implementation status in the three countries including special economic zones have analyzed that could be the spatial basis of the smart region. On the west coast of Korea facing the Yellow Sea, lots of projects related to smart cities are actively underway in Saemangeum, Yellow Sea Free Economic Zone(YESFEZ), and Incheon Free Economic Zone(IFEZ). Although the political situation is still uncertain, North Korea is analyzed to have economic and technical potential in the west coast connecting Haeju, Nampo, and Sinuiju. In Liaoning and Shandong provinces of China, smart city projects have been actively promoted in recent years especially in the state-supporting industrial cities. Restoration of economic cooperation between South Korea and China, linkage of transportation networks, vitalization of cross-border cooperation projects between China and North Korea centered on Dandong and Sinuiju, and the connecting of smart city infrastructure and services for China and South Korea's economic cooperation process will make the Yellow Sea Rim as a world prosperous economic region. However, it is necessary to establish and operate a governance system through long-term planning for transnational consultation and establishment of a promotion organization.

• Proceedings of the Korean Nuclear Society Conference
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• 1999.05a
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• pp.277-277
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• 1999

• Proceedings of the Korean Nuclear Society Conference
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• 2004.05a
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• pp.310.2-310.2
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• 2004

• Journal of the Economic Geographical Society of Korea
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• v.1 no.1
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• pp.11-32
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• 1998

Globalization of economy has a significant impact on the organization of economic Space. This paper examines the concepts of globalization and localization, major trends of the changes in the organization of economic space in the Pacific rim, and the major processes of the changes. Intra-regional trade and foreign direct investments have increased considerably in the Pacific region with the progress of globalization during the last decade. Due to the Progress of globalization of economy in the Pacific rim, some growth triangles have extended their agglomeration area beyond the national boundaries and several new industrial districts have developed. The reorganization of the economic space in the Pacific rim has been resulted from industrial restructuring of NIEs, spatial division of labor along the commodity chains, and the formation of industrial networks within the region. The ‘cooperative network strategy’has been suggested to minimize the negative effects of glocalization and for the sustainable development in the Pacific rim.

• Nuclear Engineering and Technology
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• v.42 no.1
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• pp.79-88
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• 2010

Spent $UO_2$ nuclear fuel discharged from a nuclear power plant (NPP) contains fission products, U, Pu, and other actinides. Due to neutron capture by $^{238}U$ in the rim region and a temperature gradient between the center and the rim of a fuel pellet, a considerable increase in the concentration of fission products, Pu, and other actinides are expected in the pellet periphery of high burnup fuel. The characterization of the radial profiles of the various isotopic concentrations is our main concern. For an analysis, spent nuclear fuels originating from the Yeonggwang-2 pressurized water reactor (PWR) were chosen as the test specimens. In this work, the distributions of some actinide isotopes were measured from center to rim of the spent fuel specimens by a radiation shielded laser ablation inductively coupled plasma mass spectrometer (LA-ICP-MS) system. Sampling was performed along the diameter of the specimen by reducing the sampling intervals from 500 ${\mu}m$ in the center to 100 ${\mu}m$ in the pellet periphery region. It was observed that the isotopic concentration ratios for minor actinides in the center of the specimen remain almost constant and increase near the pellet periphery due to the rim effect apart from the $^{236}U$ to $^{235}U$ ratio, which remains approximately constant. In addition, the distributions of local burnup were derived from the measured isotope ratios by applying the relationship between burnup and isotopic ratio for plutonium and minor actinides calculated by the ORIGEN2 code.

• Design & Manufacturing
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• v.10 no.3
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• pp.8-13
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• 2016

Despite technological advance, there have been several troubles in photo reaction injection molding (photo RIM) to produce ultra thin light guide panels (LGPs). In this study, micro leakage problem at cavity edge during photo RIM was investigated numerically. In order to obtain optimal processing conditions, we regulated inlet pressure of injected resin at the cavity edge and figured out micro leakage behaviors. At low inlet pressure (less than 100 Pa), though the micro leakage problem was not occurred, another problem, short shot due to not enough driving force, was appeared More than 1,000 Pa of the inlet pressure, injected resin was rapidly leaked through the micro gap at the cavity edge. Finally, we obtained optimal inlet pressure around 600 ~ 1,000 Pa. At this region, injected resin fully filled the cavity without micro leakage behavior. Based on the present study, further comparative investigations with experimental photo RIM should be performed to find optimal processing conditions for produce ultra thin LGPs.

• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.5
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• pp.92-98
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• 1989

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2006.10a
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• pp.75-76
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• 2006

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.584-587
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• 2000

The invasion genes from Salmonella typhimurium were identified by the construction of a cosmid library and subcloning genes into a plasmid vector, pGEM-7Z. The 4.65 kb fragment of the invasion-conferring genomic region of the subclone, pSV6235 was sequenced in both direction. The three open reading frames, which were located at downstream of a promoter region, were designated as sir (Salmonella invasion region)A coding for the 36 amino acids, sirB coding for the 132 amino acids and sirC for the 82 amino acids, respectively. Interesingly, the genomic region of pSV6235 was highly homologous to Yersinia enterocolitica genomic DNA for a high pathogenicity island and Salmonella enteritidis insertion element IS1351 and IS200 DNA. These results show that there could be a significant relationship between S. typhimurium, Y. enterocolitica and S. enteritidis with respect to horizontal evolution process and acquisition of virulence determinants by means of transposon, plasmid or bacteriophage.