• Journal of Wetlands Research
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• v.18 no.2
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• pp.132-147
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• 2016

In this study the Microwave Imaging Radiometer using Aperture Synthesis (MIRAS) sensor onboard the Soil Moisture Ocean Salinity (SMOS) and Advanced Microwave Scanning Radiometer 2 (AMSR2) sensor onboard the Global Change Observation Mission-Water (GCOM-W1) based soil moisture retrievals were revised to obtain better accuracy of soil moisture and higher data acquisition rate over East Asia. These satellite-based soil moisture products are revised against a reference land model data set, called Global Land Data Assimilation System (GLDAS), using Cumulative Distribution Function (CDF) matching and regression approach. Since MIRAS sensor is perturbed by radio frequency interferences (RFI), the worst part of soil moisture retrieval, East Asia, constantly have been undergoing loss of data acquisition rate. To overcome this limitation, the threshold of RFI, DQX, and composite days were suggested to increase data acquisition rate while maintaining appropriate data quality through comparison of land surface model data set. The revised MIRAS and AMSR2 products were compared with in-situ soil moisture and land model data set. The results showed that the revising process increased correlation coefficient values of SMOS and AMSR2 averagely 27% 11% and decreased the root mean square deviation (RMSD) decreased 61% and 57% as compared to in-situ data set. In addition, when the revised products' correlation coefficient values are calculated with model data set, about 80% and 90% of pixels' correlation coefficients of SMOS and AMSR2 increased and all pixels' RMSD decreased. Through our CDF-based revising processes, we propose the way of mutual supplementation of MIRAS and AMSR2 soil moisture retrievals.

• Journal of the Korean Ceramic Society
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• v.35 no.8
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• pp.775-782
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• 1998

This experiment is third study concerning BaO-{{{{ { { Pr}_{ 2} O}_{3 } }}-{{{{ { TiO}_{2 } }} (Ln=Sm, Nd, Pr, La..) system which is known to show a high dielectric constant and Q value in microwave dielectric materials. The process of cry-stallization and the microwave dielectric properties of the specimens sintered at 1220-140$0^{\circ}C$ for 2 hr was investigated in the BaO-(Na,{{{{ { { Pr})_{2 }O }_{3 } }}-{{{{ { TiO}_{2 } }} as well as BaO-{{{{ { { Pr}_{ 2} O}_{3 } }}-{{{{ { TiO}_{2 } }} system. The single phase BaPr2Ti5O14 and Ba(Nd,{{{{ { { Pr})_{2 }O }_{3 } }}Ti5O14 was finally formed from the Pr2Ti2O7 (Nd, Pr)2Ti2O7 as a secondary phase in the BaO-{{{{ { { Pr}_{ 2} O}_{3 } }}-{{{{ { TiO}_{2 } }} and BaO-(Nd, {{{{ { { Pr})_{2 }O }_{3 } }}-{{{{ { TiO}_{2 } }} system respectively The dielectric constant of the specimens sint-ered at 1280~131$0^{\circ}C$ showed the maximum value as 105(BaO-{{{{ { { Pr}_{ 2} O}_{3 } }}-{{{{ { TiO}_{2 } }} system) and 88 (BaO-(Nd,{{{{ { { Pr})_{2 }O }_{3 } }}-{{{{ { TiO}_{2 } }} system) and the Q values of them showed higher value than 1800 which are due to the maximum den-sity. However the dielectric properties of the specimens sintered at higher temperature than 131$0^{\circ}C$ were reduced due to the increases of pore which were resulted from the sudden grain growth.

• Elastomers and Composites
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• v.40 no.1
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• pp.45-52
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• 2005

Synthesis or fullerene oxides[$C_{60}(O)_n$] ($n=1{\sim}4$ or n=1) by fullerene[$C_{60}$] and several oxidants such as 3-chloroperoxy benzoic acid, benzoyl peroxide, trichloroisocyanuric acid, and chromium(VI) oxide took place under microwave irradiation. The reactivity in solid state of fullerene[$C_{60}$] with various oxidants under same microwave rendition increased in order or 3- chloroperoxy benzoic acid > benzoyl peroxide > trichloroisocyanuric acid $\simeq$chromium(VI) oxide. The MALDI-TOF-MS, UV-visible spectra and HPLC analysis confirmed that the products of fullerene oxidation were [$C_{60}(O)_n$] ($n=1{\sim}4$ or n=1).

• Proceedings of the Korean Vacuum Society Conference
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• 2009.08a
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• pp.75-75
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• 2009

• Proceedings of the Korean Magnestics Society Conference
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• 2015.05a
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• pp.144-144
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• 2015

• Proceedings of the Korean Ceranic Society Conference
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• 2003.04a
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• pp.154.1-154
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• 2003

• Proceedings of the Korean Ceranic Society Conference
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• 2003.10a
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• pp.165.2-165
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• 2003

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.93.2-93.2
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• 2010

Recently, printing and coating technologies application fields have been expanded to the energy field such as solar cell. One of the main reasons, why many researchers have been interested in printing technology as a manufacturing method, is the reduction of manufacturing cost. In this paper, We fabricated CIGS solar cell thin film layer by doctor blade methods using synthesis of CIS precursor nanoparticles ink on molybdenum (Mo) coated soda-lime glass substrate. Synthesis CIS precursor nanoparticles ink fabrication was mixed Cu, In, Se powder and Ethylenediamine, using microwave and centrifuging. Using multi coating process as we could easily fabrication a fine flatness CIS thin-film layer ($0.7{\sim}1.35{\mu}m$), and reduce a manufacture cost and process steps. Also if we use printing and coating method and solution process in each layer of CIGS solar cell (electrode, buffer), it is possible to fabricate all printed thin-film solar cell.

• Journal of the Korean Ceramic Society
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• v.31 no.8
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• pp.835-840
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• 1994

In this study, the synthesis of Ba2Ti9O20 powder having chemically homogeneous and highly pure fine particle size distribution was attempted by the oxalate method. And the effects of ZrO2 addition was investigated. The four compositions (X=0, 0.028, 0.048, 0.068) of Ba2(Ti9-x, Zrx)O20 were prepared by precipitation reaction of BaCl2, TiCl4, and ZrOCl2, with oxalic acid and NH4OH acting as a precipitating agent and a pH regulator respectively, in aqueous solution. In case of 4.8 mol% ZrO2 addition, the single phase Ba2Ti9O20 was obtained at 120$0^{\circ}C$ and its dielectric properties was excellent showing K=40.5, Q=4621 at 5.4 GHz.

• Rapid Communication in Photoscience
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• v.3 no.4
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• pp.64-66
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• 2014

Synthesis of a deuterium-labeled derivative of nitrospirobenzopyran (NSP), one of representative photochromic compounds, has been described. Four deuteriums were successfully introduced on 1-methyl and ${\alpha}$-methyne relative to spiro-carbon in the title compound with more than 95atom%D purity. Main photodegraded products of NSP were two oxindoles in acetonitrile, and additional products were formed in poly(isobutyl-methacrylate) films possibly due to restricted molecular motion in polymer matrix. Quantitative HPLC analysis revealed that partial introduction of deuterium to NSP brought a noticeable isotope effect, recognizable enhancement in photo-resistivity of NSP, i.e.,8.3% in solutions and 29% in polymeric films.