• JSTS:Journal of Semiconductor Technology and Science
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• 제3권4호
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• pp.167-174
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• 2003

This paper proposes a network processor especially optimized for content switching. With 2Gbps port capability, it integrates packet processor cluster, content-based classification engine and traffic manager on a single chip. A switch fabric architecture is also designed for scale-up of the network processor's capability over hundreds gigabit bandwidth. Applied in real network systems, the network processor shows wire-speed network address translator (NAT) and content-based switching performance.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2002년도 proceedings of the second asia international conference on tribology
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• pp.233-234
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• 2002

Diamond composites hold promise as a tribological material because of low friction and high wear resistance. We studied friction and wear of polyimide-20vol% PTFE-diamond composites in open air at room temperature, focusing on the effects of diamond size, and diamond content, sliding conditions, and mating material. Friction coefficient and wear tend to Increase with increasing diamond size and content. Composites of appropriate diamond size and content showed a friction coefficient below 0.1 and specific wear of $10^{-7}\;mm^3/Nm$. Friction and wear of composites sliding against stainless steel were higher than those of Al_2O_3$ an increase that became increasingly not able with increasing diamond size.

• Macromolecular Research
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• 제11권6호
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• pp.410-417
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• 2003

Poly(methyl methacrylate-co-acrylonitrile) [P(MMA-co-AN)]/Na-MMT nanocomposites were synthesized through emulsion polymerization with pristine Na-MMT. The nanocomposites were exfoliated up to 20 wt% content of pristine Na-MMT relative to the amount of MMA and AN, and exhibited enhanced storage moduli, E', relative to the neat copolymer. The exfoliated morphology of the nanocomposite was confirmed by XRD and TEM. 2-Acryla-mido-2-methyl-1-propane sulfonic acid (AMPS) widened the galleries between the clay layers before polymerization and facilitated the comonomers, penetration into the clay to create the exfoliated nanocomposites. The onset of the thermal decomposition of the nanocomposites shifted to a higher temperature as the clay content increased. By calculating areas of tan$\delta$ of the nanocomposites, we observed that the nanocomposites show more solid-like behavior as the clay content increases. The dynamic storage modulus and complex viscosity increased with clay content. The complex viscosity showed shear-thinning behavior as the clay content increased. The Young's moduli of the nano-composites are higher than that of the neat copolymer and they increase steadily as the silicate content increases, as a result of the exfoliated structure at high clay content.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2022년도 학술발표회
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• pp.159-159
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• 2022

Soil represents a substantial component within the global carbon cycle and small changes in the SOC stock may result in large changes of atmospheric CO₂ particularly over tens to hundreds of years. In this study, we aim to (i) evaluate the SOC stock in the topsoil 0 - 15 cm from soil physical and chemical characteristics and (ii) find the correlation of SOC and soil organic matter (SOM) for national-scale in South Korea. First of all, based on the characteristics of the soil to calculate the soil hydraulic properties, SOC stock is the SOC mass per unit area for a given depth. It depends on bulk density (BD-g/cm³), SOC content (%), the depth of topsoil (cm), and gravel content (%). Due to insufficient data on BD observation, we establish a correlation between BD and SOC content, sand content, clay content parameter. Next, we present linear and non-linear regression models of BD and the interrelationship between SOC and SOM using a linear regression model and determine the conversion factor for them, comparing with Van Bemmelen 1890's factor value for the country scale. The results obtained, helps managers come up with suitable solutions to conserve land resources.

• Journal of Animal Science and Technology
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• 제47권1호
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• pp.99-106
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• 2005

This study was carried out to investigate the effects of addition of citron peel powder(OJ 0/0, 0.60/0, 0.9 %) on proximate composition, minerals, vitamin A, C content and fatty acid composition of emulsion-type sausages. The moisture content of sausage containing 0.3% citron peel powder were significantly(P< 0.05) higher compared to those for control. The crude fat content of sausage containing citron peel powder were significantly( P< 0.05) lower compared to those for control. The crude ash content of sausage containing 0.9% citron peel powder were significantly(P< 0.05) higher compared to those for control. The minerals, vitamin A and C content of sausage containing citron peel powder were significantly(P < 0.05) higher compared to those for control. The palmitic acid(CI6: 0) and linoleic acid(CI8: 2) content of sausage containing citron peel powder were higher compared to those for control, but the palmitoleic acid(CI6: I) content of sausage containing 0.9% citron peel powder were lower. The total saturated fatty acid content of sausage containing 0.3% citron peel powder were significantly(P < 0.05) lower compared to those for control.

• Journal of Communications and Networks
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• 제17권3호
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• pp.296-305
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• 2015

Coupled schemes between service-oriented architecture (SOA) and Web 2.0 have recently been researched. Web-based content providers and telecommunications company (Telecom) based Internet protocol television (IPTV) providers have struggled against each other to accommodate more three-screen service subscribers. Since the advent of Web 2.0, more abundant reproduced content can be circulated. However, because according to increasing device's resolution and content formats IPTV providers transcode content in advance, network bandwidth, storage and operation costs for content management systems (CMSs) are wasted. In this paper, we present a user centric CMS for open IPTV, which integrates SOA and Web 2.0. Considering content popularity based on a Zipf-like distribution to solve these problems, we analyze the performance between the user centric CMS and the conventional Web syndication system for normalized costs. Based on the user centric CMS, we implement a social Web TV with device-aware function, which can aggregate, transcode, and deploy content over social networking service independently.

• Carbon letters
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• 제10권1호
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• pp.9-13
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• 2009

We propose an evaluation method of the relative content of single-walled carbon nanotubes (SWCNT) in SWCNT soot synthesized by arc discharge using UV-VIS-NIR absorption spectroscopy. In this method, we consider the absorbance of semiconducting and metallic SWCNTs together to calculate the relative content of SWCNTs with respect to a highly purified reference. Our method provides the more reliable and realistic evaluation of SWCNT content with respect to the whole carbonaceous content than the previously reported method.

• 한국수소및신에너지학회논문집
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• 제8권1호
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• pp.11-21
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• 1997

$ZrV_{0.7}Mn_{0.5}Ni_{1.2}$ alloy is attractive for anode material in Ni/MH secondary battery because of its large hydrogen storage capacity in gas-solid reaction and long cycling durability in KOH electrolyte. In this work, in order to further improve the discharge performance of this alloy electrode, the alloy was annealed by optimal condition which is for 12 hours at $1000^{\circ}C$. The alloy annealed under optimal condition had higher rate capability and discharge capacity than as-cast one. The microstructure of the as-cast and annealed alloy was investigated by scanning electron microscopy and energy dispersive spectroscopy. Ni content in the matrix was increased, being this homogenized after annealing. Additionally, The measurement of the surface area by B.E.T. analysis showed that there was little difference as-cast and annealed alloy. Therefore, improvement in the rate capability of the annealed alloy is due to increase of Ni content in the matrix.

• 한국과학교육학회지
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• 제31권6호
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• pp.827-835
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• 2011

이 연구에서는 고등학교 10학년 과학 교육과정에 최신 과학 내용을 도입한 수업이 학생들의 과학과 과학 수업에 대한 흥미에 미치는 영향을 조사하였다. 서울시에 소재한 남녀공학 고등학교 4 학급을 각 2학급씩 비교 집단과 실험 집단으로 배치하였고, 학생들의 사전 과학학업 성취도에 따라 3집단(상, 중, 하)으로 나누어분석하였다. 처치집단은 ‘반응속도’, ‘환경’, ‘과학의 탐구’단원 수업에 최신 과학기술 내용을 도입한 학습 자료를 이용하여 학습하였다. 수업 처치는 6주 동안 실시하였으며, 처치 전 후에 학생들의 과학 학습 태도 검사를 실시하였다. 연구 결과, 과학에 대한 흥미 영역에서는 학업 성취도와 수업 처치 간에 유의미한 상호작용 효과가 나타났다(p<.01). 과학 수업에 대한 흥미 영역에서는 성취도와 관계없이 모든 집단에서 수업 처치에 따른 주효과가 유의미하게 나타났다(p<.05). 최신 과학 내용을 교육과정과 연계하여 수업시간에 소개하는 것은 학생들의 과학과 과학 수업에 대한 흥미를 향상시키는데 도움이 되며, 교육과정 내용과 관련하여 최신 과학에 대해 배우기를 원하는 학생이 많은 것으로 나타났다.

• Bulletin of the Korean Chemical Society
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• 제2권2호
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• pp.60-66
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• 1981

The hypothesis that three classes of water exist in hydrogels, namely X water (free water-like), Z-water (bound water-like), and Y water (interfacial water-like), has been verified and generally accepted. To further check the validity of this hypothesis and to study the nature of X, Y, and Z water as conformation changes, several experiments have been done using Tactic Poly(2-hydroxyethyl methacrylate) (P-HEMA) gels. Thermal expansively data for tactic P-HEMA gel was obtained. In each case of isotactic and syndiotactic P-HEMA, the higher water content gels showed an extremely sharp volume change at $0^{\circ}C$, indicating the presence of normal free water-like. Lower water content gels showed no anomalous change in thermal expansion, indicating that the water is bound water-like. The medium water content gels exhibited intermediate behavior. These results were also confirmed by bulk gel conductivity measurments. The differential scanning calorimeter(DSC) experiment was simply introduced to further verify the bound water-like quantities which was obtained by the method of dilatometry and specific conductivity. Observing the amounts of X, Y, and Z water with the change of tacticity, the similar content of bound water-like may be due to the same primary structure of isotactic and syndiotactic polymer and the difference in free and interfacial water-like content may be due to the difference in secondary and tertiary structure of tactic polymer. Therefore, as the polymer conformation varies, the free and interfacial water-like content will be varied. In order to demonstrate these concepts, Russel et al.'s CPK space-filling molecular models of isotactic and syndiotactic P-HEMA was utilized.