• Proceedings of the KIPE Conference
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• 2007.07a
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• pp.533-535
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• 2007

The design of tunned filters for six-pulse thyrister converter is discussed. For electrolyzer system, the design procedure of tunned filters of AC 14.4kV power system are proposed by dynamic simulation. It is shown that these harmonic filters can meet most operational requirments. By careful specification of the transformer reactance, very low harmonic content and high power factor may be achieved at a specific operating point. The the proposed design procedure is verified with the simulation results.

• Proceedings of the Korea Information Processing Society Conference
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• 2004.05a
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• pp.1589-1592
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• 2004

현재 무선 인터넷 환경은 이동 단말에 컨텐츠 서비스를 제공할 경우, 서비스 사용자가 소유한 단말 환경의 다양성을 고려한 컨텐츠 최적화 작업을 필요로 한다. 기존 환경에서는 이런 기능을 위한 서버를 따로 설치하여 관리함으로 사용자가 늘어나게 되면 서버에 부하가 집중되어 제공되는 서비스의 질이 저하되는 문제가 발생한다. 본 논문에서는 이런 컨텐츠 최적화 기능을 망에서 제공하여 서버의 부하 집중 문제를 해결하는 이동 컨텐츠 적응형 네트워크(Mobile Contents Adaptation: MobiCAN)를 제안한다. MobiCAN 시스템은 ABone(Active Network Backbone) 데몬과 ANTS(Active Network Transfer System) 실행환경, 컨텐츠 최적화를 위한 액티브 응용으로 구성된다. 본 연구에서는 위와 같이 구성된 MobiCAN 시스템을 실제 무선 인터넷 망과 연동시킴으로 해서 액티브 네트워크의 무선 인터넷 적용 가능성을 확인하였다.

• Applied Chemistry for Engineering
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• v.9 no.7
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• pp.1030-1035
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• 1998

The porous alumina membrane was prepared from aluminum metal(99.8%) by anodic oxidation using DC power supply of constant current mode in an aqueous solution of sulfuric acid. To prevent the chemical dissolution of alumina membrane, $Al_2(SO_4)_3$, $AlPO_4$ and $Al(NO_3)_3$ which could be considered to supply $Al^{3+}$ ions were added to electrolyte solution at a reaction temperature of $20^{\circ}C$ and cumulative charge of $150C/cm^2$. Effects of these additives on the formation of porous alumina membrane were evaluated under various electrolyte concentration(5~20 wt%) and current densities($10{\sim}50mA/cm^2$). The membrane surfaces which were prepared in electrolyte solution with all the additives except $Al_2(SO_4)_3$ were damaged. However, when $Al_2(SO_4)_3$ was added to the $H_2SO_4$ solution, an uniform surface of porous alumina was obtained. Also, it was shown that the pore size of membrane was nearly independent on the quantity of $Al_2(SO_4)_3$ added at same electrolyte concentration and current density.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.7 no.4
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• pp.213-218
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• 2009

Electrowinning process recovers uranium with actinide elements from spent fuels and is a key step in the Pyroprocessing because of proliferation resistance. An analysis of heat transfer of the Electrowinning cell was conducted to develop basic tool for designing engineering-scale Electrowinner. For the calculation of the heat transfer, ANSYS CFX commercial code was adapted. As a result of the calculation, the vertical Heating Zone length had great effect upon temperature of LiCl-KCl eutectic salt. To maintain constant temperature in the salt, the Heating Zone length should be three times longer than the height of the salt. However, the argon and salt temperatures were barely affected by the Cooling Zone length. The temperature under the Cell cover was mainly influenced by the number of the cooling plates. When the cooling plates were installed more than the number of 5, temperature under the cover was maintained below $250^{\circ}C$. These temperature properties had similar tendency toward the temperature of the Cell which was measured from experiments, Simulated heat transfer information from this study could be used to design engineering-scale Electrowinner.

• Resources Recycling
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• v.24 no.2
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• pp.62-68
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• 2015

The high pure tin production was conducted from crude-tin containing waste solder by electro-refining process. The electro-refining process maintained at 0.2V produced tin with purity of 99.98%, whereas a little increase of voltage to 0.3 V resulted tin purity of 99.92%. The high pure tin of 3N in the present process was produced by fixing the voltage at 0.3V. Considering the high pure tin production, the current density was maintained within $100-120A/m^2$ with current efficiency of 94%. Addition of sulfuric acid of 20 ~ 25 g/L to the electrolyte solution was performed in order to keep Pb (lead) concentration below 100 mg/L in the final tin product. The anode slime generated during electro refining process was analyzed by X-ray diffraction (XRD) study to understand the phases of impurities in it. It detected the presence of Cu and Ag in the slime as in the form of $Cu_6Sn_5$, $Ag_3Sn$, whereas Pb occurred as $PbSO_4$ compound.

• Applied Chemistry for Engineering
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• v.22 no.1
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• pp.67-71
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• 2011

The cathodic active material of $Li/SO_2Cl_2$ battery is $SO_2Cl_2$, which is the solvent of an electrolyte. It is referred to as a catholyte, a compound word of cathode and electrolyte. As the battery discharges, the catholyte burns out. And thus, the characteristics of the $SO_2Cl_2$ in the battery determine the capacity. In addition, the transition minimum voltage (TMV) and the voltage delay deviation of $Li/SO_2Cl_2$ battery are due to the passivation film formed by the reaction between an electrolyte and Li. Impurities in the electrolyte, such as moisture or heavy metal ions, will accelerate the growth of the passivation film. Therefore, a technology must be established to purify an electrolyte and to ensure the effectiveness of the purification method. In this research, $LiAlCl_4/SO_2Cl_2$ was manufactured using $AlCl_3$ and LiCl. Its concentration, the amount of moisture, and the metal amount were evaluated using an ionic conductivity meter, a colorimeter, and FT-IR.

• Applied Chemistry for Engineering
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• v.7 no.2
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• pp.362-370
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• 1996

The performance of The performance of $Li/V_6O_{13}$ cell and the electrochemical properties of polymer electrolyte based on poly(acrylonitrile)[PAN] was investigated. The ionic conductivity of polymer electrolyte showed $2.3{\times}10^{-3}S/cm$ and the compatibility with lithium electrode was excellent. Also, it showed the electrochemical stability up to 4.3V(vs. $Li^+/Li$). The cell reaction of $Li/V_6O_{13}$ was dominated by the interfacial resistance between $V_6O_{13}$ electrode and polymer electrolyte. The diffusion coefficient of lithium ion within $V_6O_{13}$ was $2.7{\times}10^{-9}{\sim}4.2{\times}10^{-8}cm^2/sec$. The utilization of $V_6O_{13}$ active material was 95% at C/8($50{\mu}A/cm^2$) and 82% at C/4($100{\mu}A/cm^2$), respectively.

• Journal of the Korean Electrochemical Society
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• v.5 no.3
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• pp.159-163
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• 2002

The use of lithium metal anode at lithium metal secondary battery can provide the very high energy density. Nevertheless, there are some problems that are short cycle life, lack of safety and poor thermal stability. Cycle life and cycling efficiency decline due to passivating films, dendritic lithium and increasing surface film by the reaction of lithium metal and electrolyte. This work investigated the additive effect of benzene, toluene, tetram-ethylethylenediamine, into the electrolyte. The cycling efficiency and cyclability are improved. The reason is confirmed by decreasing film resistance and increasing polarization resistance at AC impedance analysis. Electrolyte additive has a relatively less reactivity than electrolytes lithium and is adsorbed on lithium leading to suppression of the reaction between the electrolyte and lithium as well as an improvement in the lithium deposition mophology.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.1
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• pp.439-444
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• 2012

This study was conducted to determine the effects of electrolytic water washing(EWW) and tap water washing(TWW) on proximate composition, color difference and SDS-PAGE changes of Mackerel(Scomber japonicus) muscle. Moisture contents of washed mackerel sediments EWW were much higher than TWW(p<0.05). Crude proteins of washed mackerel sediments EWW were 1% lower than TWW. Crude lipides had same results with crude proteins. Hunter value L, a, b were tested to each samples. $L^*$ values of TWW were higher than EWW. Both of $aL^*$ values were lower with washing times in order of 3rd>2nd>1st(p<0.05) but 2nd and 3rd of EWW were not significantly different(p>0.05). $b^*$ values were not different between the TWW and EWW(p<0.05). SDS-PAGE patterns of EWW muscle sediments were more darkeness 205KD band than TWW muscle sediments. In these results said that EWW is better than TWW for red meat kamaboko industry, respectively.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.10a
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• pp.381-382
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• 2006