• Proceedings of the KSME Conference
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• 2008.11a
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• pp.333-337
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• 2008

This study investigates crack propagation behavior of Sn-3.0Ag-0.5Cu solder under pull-push loading conditions. Fatigue Crack Growth (FCG) tests were conducted on Center Cracked Plate (CCP) specimens in fast-fast (pp) strain waveform. The fast-slow (pc), slow-fast (cp) and slow-slow (cc) strain waveforms were also used to study the effect of strain rates. The crack propagation rates for the four strain waveforms were correlated with J-integral range and a scatter band of factor 4 was found. The crack growth rates for the pc waveform was highest, followed by cp, cc and then pp waveforms.

• Proceedings of the CALSEC Conference
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• 2001.08a
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• pp.379-391
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• 2001

In this paper, we presented function catalogs that Internet content transcoding system for heterogeneous client devices must offer, and, we proposed content transcoding framework architecture that is good in extensibility. This transcoding framework can accommodate each transcoder in efficient way using device capability and user preference information based on W3C's CC/PP and Wap forum's UAProf specification. This architecture offers advantages that can add developed transcoder dynamically in Plug-In form later.

• Advances in materials Research
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• v.3 no.3
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• pp.129-137
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• 2014

Biocomposites from polypropylene (PP) and corn cob (CC) were investigated. The effect of corn cob content and maleic anhydride polypropylene (MAPP) as compatibilizer were studied. Results showed that addition of corn cob (CC) in PP have decreased the tensile strength and elongation at break, whereas modulus of elasticity of biocomposites increased. The biocomposites with the MAPP as compatibilizer exhibited higher tensile strength and modulus of elasticity compared biocomposites without MAPP. The morphology study of biocomposites indicates that enhanced the interfacial interaction and adhesion between filler and matrix with the presence of MAPP.

• Proceedings of the IEEK Conference
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• 1998.06a
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• pp.530-533
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• 1998

In this paper, a new scheme of a boosted voltage generator (BVG) is designed for low powr DRAM's. The designed BVG can supply stable $V_{pp}$ using a new circuit operting method. This method controls charge pumping capability by switching the supply voltage and ring oscillator frequency of driving circuit, so the BVG can save area and reduce the powr dissipation during $V_{pp}$ maintaining period. The charge pumping circuit of the BVG suffers no $V_{T}$ loss and is to be applicable to low-voltage DRAM's. $V_{pp}$ level detecting circuit can detect constant value of $V_{pp}$ against temperature variation. The level of $V_{pp}$ varies -0.55%~0.098% during its maintaining period. Charge pumping circuit can make $V_{pp}$ level up to 2.95V with $V_{cc}$ =1.5V. The degecting level of $V_{pp}$ level detecting circuit changes -0.34% ~ 0.01% as temperature varies from -20 to 80.deg. C. The powr dissipation during V.$_{pp}$ maintaining period is 4.1mW.W.1mW.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.2
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• pp.211-216
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• 2003

The objective of this study was to determine the degradability of cassava chip (CC), cassava waste (CW), yellow sweet potato (YP), white sweet potato (WP), purple sweet potato (PP), corn meal (CM), and rice bran (RB) using in situ technique. Two ruminally fistulated steers with an average weight of $303{\pm}10kg$ were used to determine in situ degradabilities of DM and OM. Seven feed sources were weighted in nylon bags ($38{\mu}m$ pore size) and incubated ruminally for 1, 2, 4, 6, 8, 12, 24, and 48 h. The results showed that asymptote (a+b) and effective degradability (ED) of DM of energy sources ranked from the highest to the lowest; CC, YP, WP, PP, RB, CW, and CM (99.3, 92.5; 97.6, 87.9; 97.5, 87.9; 97.2, 87.8; 87.5, 63.6; 78.6, 63.0 and 81.7; 59.3, respectively) and for OM asymptote (a+b) and effective degradability (ED) were similar to those of degradation of DM (99.4, 93.4; 98.8, 89.8; 98.5, 89.4; 98.4, 88.1; 92.4, 65.8; 85.1, 66.9 and 83.6, 63.3, respectively). It was concluded that disappearance characteristic of CC was the highest and it may potentially facilitate the achievement of optimal ruminal availability of energy: protein especially with NPN for microbial protein synthesis.

• KSBB Journal
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• v.14 no.6
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• pp.696-701
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• 1999

The enzymatic hydrolysis of Castor oil for the mass production of ricinoleic acid was studied to find out the optimum conditions such as solvents and the weight ratio of substrate to enzyme. Three different lipases were tested for the hydrolysis of castor oil: lipase from Porcine Pancrease(lipsase PP), lipase from Candida cylindracea(lipase CC), lipase from Candida Rugosa(lipase CR). The poor mass transfer in water caused a low degree of hydrolysis of castor oil. To overcome this problem, organic solvents were used. Among organic solvents tested, hydrophobic solvents gave better results of hydrolysis than hydrophilic solvents. Organic solvents also lowered or changed the effect of pH. Isopropyl ether made complete hydrolysis of castor oil. The ratio of water to isopropyl ether and the ratio of weight ratio of lipase to castor oil were important for the hydrolysis of castor oil. At 30$^{\circ}C$ castor oil was completely hydrolyzed by 4 wt% of lipase in the mixture of isopropyl ether and water(1:1 in volume).

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.541-542
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• 2009

In this study, the properties of concrete with various fiber(cellulose, PP, PVA) such as slump, air content, compressive strength, tensile strength and bending strength were examined. In addition, field application of press concrete with disperse cellulose fiber in liquid were investigated.

• Proceedings of the KAIS Fall Conference
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• 2010.05b
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• pp.1137-1140
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• 2010

PP에 용융온도 조절을 위한 첨가제로 ZnO와 ADCA를 첨가하여 발포제의 온도를 약 $165^{\circ}C$로 조절 하였다. 이러한 혼합 분말은 $178{\sim}208^{\circ}C$ 온도범위의 금형에서 약 3분 동안 가압성형 되었다. $198^{\circ}C$, 발포제 1.0wt%에서 비교적 우수한 기공 분포를 나타냈다. 그 보다 낮은 온도에서는 기공형성이 충분치 않았고, 그 이상에서는 기공이 불균일하게 분포하여 측면이나 상부에 밀집되면서 더욱 큰 기공을 형성하는 경향을 보였다. 이렇게 제조된 PP 시트의 밀도는 0.518g/cc이었고, 기공률로 약 47%에 해당하였다.

• Carbon letters
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• v.22
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• pp.70-80
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• 2017

Activated carbons (ACs) have been used as electrode materials of electric double-layer capacitors (EDLC) due to their high specific surface areas (SSA), stability, and ecological advantages. In order to make high-energy-density ACs for EDLC, petroleum pitch (PP) pre-carbonized at $500-1000^{\circ}C$ in $N_2$ gas for 1 h was used as the electrode material of the EDLC after KOH activation. As the pre-carbonization temperature increased, the SSA, pore volume and gravimetric capacitance tended to decrease, but the crystallinity and electrode density tended to increase, showing a maximum volumetric capacitance at a medium carbonization temperature. Therefore, it was possible to control the crystalline structure, SSA, and pore structure of AC by changing the pre-carbonization temperature. Because the electrode density increased with increasing of the pre-carbonization temperature, the highest volumetric capacitance of 28.4 F/cc was obtained from the PP pre-carbonized at $700^{\circ}C$, exhibiting a value over 150% of that of a commercial AC (MSP-20) for EDLC. Electrochemical activation was observed from the electrodes of PP as they were pre-carbonized at high temperatures above $700^{\circ}C$ and then activated by KOH. This process was found to have a significant effect on the specific capacitance and it was demonstrated that the higher charging voltage of EDLC was, the greater the electrochemical activation effect was.

• Journal of the Korea Convergence Society
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• v.8 no.10
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• pp.61-66
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• 2017

Recently, IoT technology is rapidly developing with the keyword "Anytime, Anywhere, Convenient". In addition, security problems in IoT systems are exploding and the damage is increasing as well. In this paper, we propose a method to develop IoT system safely by using internationally recognized CC evaluation in ICT by identifying the standardization and security technology development status defining IoT system security requirements. For this purpose, IoT system and service security aspects are analyzed. Based on this, it is possible to design the security functional requirements and to demonstrate the rationale of the security objective through the correspondence relation, and it is possible to design the protection profile for the IoT system. This is a sufficient basis for the development methodology to be presented in this paper because it is used as a means of referring to the set of security requirements of administrators, developers, and users.