• The KIPS Transactions:PartA
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• v.9A no.4
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• pp.535-546
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• 2002

According as the users can connect to remote hosts at anytime by using internet, the demand of non-stop system is increased. Also, the research about on-line adding/deleting disks and hosts are progressed. This paper suggests that the method of reducing additional operation when we add disks to the stripping system. That method can fast mapping like equation based mapping method because of using so-called SZIT(Striping Zone Information Table) and equations. And that method can reduce the relocation overhead in striping system at adding disks.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.11a
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• pp.152-155
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• 2003

Ashing of photoresist was investigated in dielectric barrier discharges in atmospheric pressure by changing applied voltage, frequency, flow rate. we analyzed the plasma by Optical Emission Spectroscopy(OES) to monitor the variation of active oxygen species. Another new peaks of oxygen radical is observed by addition of argon gas. This may explain the increase in ashing rate with argon addition. With the results of Optical Emission Spectroscopy(OES), we can find the optimized ashing conditions. MIS capacitor for monitoring charging damage by the plasma was also studied. The results suggest the dielectric barrier discharges(DBD) can be an efficient, alternative Plasma source for general surface processing.

• Nuclear Engineering and Technology
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• v.50 no.6
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• pp.869-876
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• 2018

The force of a direct current (DC) electromagnetic pump used to transport liquid lithium was analyzed to optimize its geometrical and electrical parameters by numerical simulation. In a heavy-ion accelerator, which is being developed in Korea, a liquid lithium film is utilized for its high charge-stripping efficiency for heavy ions of uranium. A DC electromagnetic pump with a flow rate of $6cm^3/s$ and a developed pressure of 1.5 MPa at a temperature of $200^{\circ}C$ was required to circulate the liquid lithium to form liquid lithium films. The current and magnetic flux densities in the flow gap, where a $Sm_2Co_{17}$ permanent magnet was used to generate a magnetic field, were analyzed for the electromagnetic force distribution generated in the pump. The pressure developed by the Lorentz force on the electromagnetic force was calculated by considering the electromotive force and hydraulic pressure drop in the narrow flow channel. The opposite force at the end part due to the magnetic flux density in the opposite direction depended on the pump geometrical parameters such as the pump duct length and width that defines the rectangular channels in the nonhomogeneous distributions of the current and magnetic fields.

• Toxicological Research
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• v.30 no.4
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• pp.311-316
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• 2014

For the detection of trace copper to be used in medical diagnosis, a sensitive handmade carbon nanotube paste electrode (PE) was developed using voltammetry. Analytical optimized conditions were found at 0.05 V anodic peak current. In the same conditions, various common electrodes were compared using stripping voltammetry, and the PE was found to be more sharply sensitive than other common electrodes. At optimum conditions, the working ranges of $3{\sim}19{\mu}gL^{-1}$ were obtained. The relative standard deviation of $70.0{\mu}gL^{-1}$ was determined to be 0.117% (n = 15), and the detection limit (S/N) was found to be $0.6{\mu}gL^{-1}$ ($9.4{\times}10^{-9}M$). The results were applied in detecting copper traces in the kidney and the brain cells of fish.

• Resources Recycling
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• v.26 no.5
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• pp.3-11
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• 2017

Solvent extraction is an important process to recover pure gold and silver from various leaching solutions. The present work reviews the aqueous chemistry and solvent extraction separation of gold (I, III) and silver (I) from several leaching systems such as cyanide, thiocyanate, thiosulfate, thiourea and chloride medium. The extraction and separation behavior of gold (I, III) and silver (I) by various single and mixtures was compared on the basis of extraction reaction and the selectivity from these mediums. The chloride medium is recommended for the separation of gold and silver by solvent extraction in terms of extraction and stripping efficiency.

• Journal of Hydrogen and New Energy
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• v.32 no.5
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• pp.401-409
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• 2021

The combination of different concentrations of ZnSO₄ in acidic solution as electrolyte in Zn-air batteries was investigated by Zn symmetrical cell test, half-cell and full cell tests. Using 1 M ZnSO₄ + 0.05 M H₂SO₄ as electrolyte and MnO₂ as air cathode catalyst with Zn foil anode, this combination had a satisfactory performance with balance of electrochemical activity and stability. Its electrochemical activity was matched to or even better than the PtRu catalyst in different current density. And its cycle life was improved (more than 100 cycles stable) by suppressing the growth of zinc dendrites on anode obviously. This electrolyte overcame the shortcomings of alkaline electrolyte that are easy to react with CO₂ in the air, severely growth of Zn dendrites caused by uneven plating/stripping of Zn.

• Resources Recycling
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• v.30 no.5
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• pp.32-37
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• 2021

Thorium extraction and possible separation from monazite leaching solution was studied. Primary amine Primene JM-T was select ed for t horium ext ract ion processing. Various experiment s were t est ed and est ablished for t he t horium liquid -liquid extraction process. The screening of extractant, lower pH conditions, extractant variation and extraction isotherms construction, and finally, stripping studies were established.

• Journal of Korea Society of Digital Industry and Information Management
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• v.14 no.4
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• pp.101-107
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• 2018

In the stripping scan square wave voltammetry (SV+SWV) polarography that is often used to analyze the concentration of heavy metals in water, we must measure the point where the faradic current that flows by the pure oxidation-reduction reaction at the electrode is greater than the capacitive current, the frequency cannot be too high. Therefore we wanted to find the frequency range that can be measured. In order to do this, we came up with a method to analyze the signal using FPGA Soc. With this method, the frequency of the square wave was increased from 10Hz to 400Hz by 10Hz, and the measuring time of the square wave was changed from 96.695% to 96.765% by 0.005% while 1600 experiments were conducted. As a result, the frequency of the square wave maintained a stable area of potential-current within 320Hz and it was possible to measure the potential-current signal when calculating the measuring time within the frequency range of 96.7155%.

• The Journal of the Korean dental association
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• v.57 no.6
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• pp.326-332
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• 2019

Extraction treatment has been used for a long time to treat crowding or lip protrusion patients and still extraction decision is the most difficult and important decision during diagnosis and treatment planning. If the amount of crowidng is severe, premolar extraction is often considered. Because of their location, premolar extractions would seem to allow for the most straightforward relief of crowding and the improvement of soft tissue profile. But patients and their parents often prefer nonextraction approach if possible and such a preference gives us serious question about the boundary of nonextraction treatment. Because Orthodontic Mini-Implant (OMI) become popular these days, distalization of posterior teeth can be obtained easily without patient's compliance. For this reason, many orthodontists are trying to treat crowding patient with nonextraction than before. But sometime, unexpected side effects are observed including unesthetic profile, impaction of second molar and long treatment time. All the tools for space gaining - extraction, arch expansion, molar distalization and interproximal enamel reduction - have their limitations and indications. Possible side effects and limitations should be carefully considered during the treatment planning. Although Korean patients usually require extraction more often than US or European patients, more knowledge about the tools for space gaining would help us to decrease the rate of extraction and the problems during treatment of crowding patients.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.2
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• pp.33.3-34
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• 2018

Galaxy clusters contain a diffuse component of stars outside galaxies, that is observed as intracluster light (ICL). Since the ICL abundance increases during various dynamical exchanges of galaxies, the amount of ICL can act as a measurement tool for the dynamical stage of galaxy clusters. There are two prominent ICL formation scenarios; one is related to the brightest cluster galaxy (BCG) major mergers, and the other to the tidal stripping of galaxies. However, it is still under debate as to which is the main ICL formation mechanism. In this study we improve on earlier observational constraints of the ICL origin, by investigating it in a massive fossil cluster at z~0.47. Fossil clusters are believed to be dynamically matured galaxy clusters which have dominant BCGs. Recent simulation studies imply that, BCGs have assembled 85~90% of their mass by z~0.4 (e.g., Contini et al. 2014). Thus our target is an optimal test bed to examine the BCG-related scenario. Our deep images and Multi-Object Spectroscopic observations of the target fossil cluster (Gemini North 2018A) allow us to extract the ICL distribution, ICL color map and ICL fraction to cluster light. We will present a possible constraint of the ICL origin and discuss its connection to the BCG and the host galaxy cluster.