• Proceedings of the Korean Information Science Society Conference
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• 2006.10d
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• pp.135-139
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• 2006

Today's social networking services have tens of millions of users, and are growing fast. Their sheer size poses a significant challenge in capturing and analyzing their topological characteristics. Snowball sampling is a popular method to crawl and sample network topologies, but requires a high sampling ratio for accurate estimation of certain metrics. In this work, we evaluate how close topological characteristics of snowball sampled networks are to the complete network. Instead of using a synthetically generated topology, we use the complete topology of Cyworld ilchon network. The goal of this work is to determine sampling ratios for accurate estimation of key topological characteristics, such as the degree distribution, the degree correlation, the assortativity, and the clustering coefficient.

• Bulletin of the Korean Chemical Society
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• v.35 no.1
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• pp.83-86
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• 2014

Poly(A) polymerase (PAP) play an essential role for maturation of mRNA by adding the adenylate residues at the 3' end. PAP functions are regulated through protein-protein interaction at its C-terminal region. In this study, cyclophilin A (CypA), a member of the peptidyl-prolyl cis-trans isomerase family, was identified as a partner protein interacting with the C-terminal region PAP. The interaction between PAP and CypA was inhibited by the immunosuppressive drug cyclosporine A. Deletion analysis revealed that the N-terminal 56 residues of CypA are sufficient for the interaction with PAP. Interestingly, we observed that PAP and CypA colocalize in the nucleus during SDF-1-induced chemotaxis, implying that CypA could be involved in the regulation of polyadenylation by PAP in the chemotactic cells.

• Journal of the Optical Society of Korea
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• v.12 no.3
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• pp.170-173
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• 2008

In this study, we simulated a statistical model of FCS(fluorescence correlation spectroscopy) based on a Poisson process to understand and explain observations of the experiment performed on molecules of ultra-low concentration by the home-built laser-scanning confocal microscope. The statistical model confirmed that the relative mean square amplitude of fluctuations is shown to be inversely proportional to the average number of molecules, even in the ultra-low concentration, if some conditions are satisfied. Signal-to-noise ratio and the variability of dwelling time under the confocal volume were found to be effective conditions for the experiment.

• Proceedings of the Korea Society of Design Studies Conference
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• 2001.05a
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• pp.72-73
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• 2001

• Proceedings of the Korean Nuclear Society Conference
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• 2005.05a
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• pp.467-468
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• 2005

Low cycle fatigue test results of Type 316 stainless steel in $310^{\circ}C$ water environment can be summarized as follows. 1. Cyclic stress response of Type 316 stainless steel shows negative strain rate sensitivity, primary hardening and secondary hardening. 2. Fatigue life in $310^{\circ}C$ water environment was shorter than fatigue life in room temperature air environment. This was because of water environment and temperature effects.

• Bulletin of the Korean Space Science Society
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• 2004.10b
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• pp.293-295
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• 2004

The Engineering Model of on-board computer was developed and tested completely with other sub-systems for STSAT-2. We designed the on-board computer of STSAT-2 which has some improved features compared with that of STSAT-l. A remarkable change is that the on-board computer has a structure of centeralized network communication without a Network Controller of the STSAT-l. That is, the on-board computer directly manages a satellite network. In addition, as many logics are implemented by Field Programmable Gate Array, so we can reduce the weight and size of on-board computer. Also, the developed on-board computer has more improved tolerance against Single Event Upsets and faults than that of the STSAT-l.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.171-172
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• 2006

In first-order moving-average Cauchy noise, the maximum likelihood (ML) and suboptimum ML (S-ML) detectors are analyzed in terms of the bit-error-rate in impulsive environment. Despite reduced complexity and simpler structure, the S-ML detector exhibits practically the same performance as the ML detector.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.806-809
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• 2009

Epoxy functionalized organic-inorganic hybrid materials (hybrimers) were synthesized by sol-gel reaction for application in OLED barrier coating. By using the calcium degradation method, the oxygen transition rate (OTR) and water vapor transition rate (WVTR) measured so far is $10^{-2}cc/m^2$-day for oxygen and $10^{-1}g/m^2$-day for water molecules with single hybrimer coating film, respectively. Encapsulated OLED devices have life time of 14hrs of a single hybrimer barrier coating and 29hrs of hybrimer/inorganic double barrier coatings at $25^{\circ}C$ and 60% relative humidity.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.337-338
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• 2009

A flexible photoluminescent display device was proposed and fabrication technology with a low process temperature was investigated in order to improve its reliability. The proposed flexible photoluminescent display showed good characteristics in reliability and flexibility. The lifetime of the proposed flexible photoluminescent displays with organics components is estimated to be approximately more than 10,000 hours.

• Proceedings of the KIPE Conference
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• 2013.07a
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• pp.335-336
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• 2013

본 논문에서 금속 차폐 공간 내 원거리 무선 전력전송 기술의 적용방법을 제시한다. 논문에서 고려된 금속 차폐 공간은 무선 전력전송 송수신코일의 후면 및 천장, 바닥에 위치하는 철, 알루미늄, 페라이트 3종류의 금속판들로 구성된다. 본 논문에서는 유한요소해석 시뮬레이션(Ansoft Maxwell)을 통해 송수신코일 간 자기결합 측면에서 철, 페라이트 금속판 보다 우수한 알루미늄 금속판의 특성을 검토하였다.