• Journal of the Korean Electrochemical Society
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• v.14 no.2
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• pp.98-103
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• 2011

[ $Li[Ni_{0.8}Co_{0.15}Al_{0.05}]O_2$ ]cathode material for lithium secondary battery is obtained using co-precipitation method. To determine the optimal metal solution concentration value, the CSTR coprecipitation was carried out at various concentration values(1-2 mol/L). The surface morphology of coated samples was characterization by SEM(scanning electron microscope) and XRD (X-Ray Diffraction)analyses. Impedance analysis and cyclic voltammogram presented that internal resistance of the cell was dependent upon the concentration of metal solution. such data is very helpful in determining the optimal content of metal solution concentration to enhancing electrochemical property by adjusting powder size distribution and crystal structure.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.7
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• pp.589-594
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• 2014

Recently, higher capacity and energy density of lithium ion batteries are increasingly demanded for enhancing their performance in view of the rise in the commercial distribution of electric and hybrid vehicles. Computational analysis of a porous structure of vanadium pentoxide cathode was performed, employing a phase field model. The incipient model was designed as a spherical structure with cylindrical-shaped pores. Modifying the diameters and lengths of the pore cylinder and the number of pores, we considered different conditions for the porous vanadium pentoxide cathodes for analyzing their effect on the amount of lithium ion intercalated to them. Subsequently, we optimized the porous structure to contain the largest amount of intercalated lithium ion during discharge.

• Economic and Environmental Geology
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• v.40 no.4
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• pp.375-387
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• 2007

The Iksan Mireuksaji stone pagoda, designated as national treasure No. 11 in Korea, has been in the process of disassembling for reconstruction as part of the cultural heritage conservation program. The pagoda is mainly consisting of granite, which is relatively resistant to weathering. However, it has lost its original rock color due to various contaminants deposited at the surface since it exposed to the atmospheric environment long time. In this research, we categorized the secondary inorganic contaminants into the genetic type, and also quantitatively examined occurrences and types of pollutants in the oxidation area of the pagoda surface in which the area is clearly distinguished by naked eyes. Geochemical behavior of soluble pollutants through reaction experiments are demonstrated, and effective methods of cleaning for the conservation and scientific applicability of the surface cleaner are also studied.

• Korean Journal of Clinical Laboratory Science
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• v.49 no.1
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• pp.40-47
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• 2017

Granulosa cells, which surround the oocyte within the ovarian follicle, play an essential role in creating conditions required for the development of oocytes and follicles. The solute carrier family (SLC) is comprised of influx transporters of steroidal hormones, various drugs, and several other substrates. The differential expression of selected DEGs was confirmed using in situ hybridization analysis. SLC23A3 and SLC39A10 were highly expressed in the ovary. The SLC39A10 gene was expressed in the primordial follicle stage, but SLC23A3 was expressed in the growing follicle stage. Contrastingly, the expression of SLC23A3 was increased in granulosa cells at the growing follicle stage. The differential expressions of SLC23A3 and SLC39A10 between the primordial and primary follicles were additionally confirmed by using follicle isolations. The gene expression profile from the present study may provide insight for future studies on the mechanism(s) involved in primordial-primary follicular transition and suggestions to promote follicular development in ovarian dysfunction.

• Journal of the Korean Vacuum Society
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• v.16 no.3
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• pp.181-186
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• 2007

We have investigated and analyzed the effects of the evaporation rate of MgO films on the MgO properties and the discharge characteristics of a plasma display panel(PDP). The MgO properties such as the crystal orientation, the surface roughness, the film structure, and cathode-luminescence (CL) spectra were inspected using XRD (X-ray diffraction), AFM(atomic force microscopy). And the discharging characteristics of the PDP such as the firing voltage, discharging current, and luminescence were measured using a vacuum chamber with oscilloscope (TDS 540C), current probe (TCP-312A), color meter (CS-100A) and etc. From the experiments results we confirmed the optimum evaporation rate at $5{\AA}/sec$, the MgO properties were shown to be strongly dependent on the evaporation rate, and the MgO properties had an effecton the optical and electrical characteristics. In other words, if the evaporation rates increase than $5{\AA}/sec$, the intensity of (200) orientation and cathode-luminescence (CL) spectra reduce, and the firing vlotage was increased. So the luminuous efficiency grows worse.

• Journal of Wetlands Research
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• v.15 no.4
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• pp.471-476
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• 2013

The operating conditions of sludge disposal for sanitary paper manufacturing wastewater treatment plant were monitored on the basis of daily check sheets during the 3 years of operation. Generated wastes were mainly composed of 79% of sludge, 14% of ash, 5% of waste synthetic resin and 2% of etc. Maximum sludge was produced to 233 ton and the average was 113 ton daily, where the primary sludge occupied 85% and 15% for the secondary sludge. The concentration of coagulant for sludge dewatering was extremely exceeded and the additional experiment such as jar-test was required for the establishment of proper dosage. Presently, the generated sludges were partially treated outside and were also partly handled inside. In the future, most sludges will be expected to be treated to recycling material for the iron industry.

• Korean Journal of Materials Research
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• v.2 no.1
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• pp.35-42
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• 1992

Thermal behavior of residue and damaged layer formed by reactive ion etching (RIE) in $CHF_3/C_2F_6$ were investigated using X-ray photoelectron spectroscopy(XPS) and secondary ion mass spec-trometry(SIMS) techniques. Decomposition of polymer residue film begins at $200^{\circ}C$ and above $400^{\circ}C$ carbon compound as graphite mainly forms by in-situ resistive heating. It reveals that thermal decomposition of residue can be completed by rapid thermal anneal treatment above $800^{\circ}C$ under nitrogen atmosphere and out-diffusion of carbon and fluorine of damaged layer is observed.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.369-372
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• 2003

Korea companies have been faced with the demand of environmental changes abroad by suffering Economic Crisis at 1997. In fact, these demand that modern firms are in the keen struggles for existence is the essential condition though of the age of Economic Crisis. Coping with these situation. these companies are making desperate efforts, which are reorganization, renovation, improvement, however, the procedure or the result about these efforts of change have to be checked wisely. That is, the firms have to meet requirement that could enhance their values because organization structure that is not efficient to growth of firms produces a quite contrary result. Such phenomenon is applicable to construction firm as well as limited with partial companies. Therefore, before forming a efficient organization structure, comparing and analyzing the strategy or financial statement according to construction firm, this study will try to grasp a characteristic of organization.

• Journal of the Mineralogical Society of Korea
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• v.15 no.4
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• pp.305-314
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• 2002

The dehydration of hexadecyltrimethylammonium (HDTMA)-exchanged montmorillonite has been studied using X-ray diffractometry (XRD) and differential scanning calorimetry (DSC). The dehydration in HDTMA-montmorillonite seems to influence the swelling behavior of the organo-clay during heating. The basal d(001) spacing vs temperature curve of the HDTMA-montmorillonite has one broad swelling edge with a shoulder on the low-temperature side. We believe that the shoulder at $100^{\circ}C$ for the HDTMA-montmorillonite is due to interlayer swelling induced by the initial rearrangement of surfactants, and the second edge at $200^{\circ}C$ is caused by interlayer swelling resulting from the secondary vertical reorientation of alkyl chains. It seems that the dehydration of organo-clay induces a reorientation of the alkyl chains by transition to more vertical position relative to the silicate sheets, allowing instantly greater d-spacing.

• Journal of the Korean School Mathematics Society
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• v.12 no.4
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• pp.473-492
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• 2009

Recently there has been a high request for support for teachers' professional development and quality control to meet the demand of educational policy to introduce teacher evaluation, master teacher status, incentives for teacher competency, etc. It has been suggested that reeducation and support for professional development would be more effective to beginning teachers with a high developmental potential than to experienced teachers with routinized instruction. Since 2005, KICE-TLC has conducted research on the development of teacher supporting programs such as teaching consultation and pedagogical content knowledge(PCK) in school subjects. In line with the current education policy and previous research by KICE, this research has been conducted to meet the need for novice teacher induction by developing consulting program focused on PCK. The goal of this research was to (1) explore the in-depth meaning of PCK in light of teaching consultation, (2) conduct a preliminary study on how to develop teaching consulting programs for secondary beginning teachers, (3) develop teaching consulting programs focused on pedagogical content knowledge(PCK), and (4) suggest implications for educational policy regarding pre-service and in-service teachers' continuing professional development and support.