• Resources Recycling
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• v.27 no.4
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• pp.29-35
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• 2018

In this study, the electrochemical redox behavior of neodymium in non-aqueous electrolytes was investigated to confirm the possibility of neodymium metallurgy at room temperature. The non-aqueous electrolytes include ionic liquids such as $[C_4mim]PF_6$, $[C_4mim]Cl$, and $[P_{66614}]PF_6$, ethanol which are highly soluble in neodymium salts, and mixed electrolytes based on carbonate with highly electrochemical stability. The electrochemical redox properties of neodymium were better than those of other electrolytes in the case of the mixed electrolyte based on ethylene carbonate (EC)/di-ethylene carbonate (DEC). Ethanol was added to improve the physical properties of the mixed electrolyte. Thorough the analysis about ionic conductivity of EC/DEC ratio, ethanol content and $NdCl_3$ concentration, the best electrolyte composition was 50 vol% content of ethanol and 0.5 M of $NdCl_3$. Using cyclic voltametry and linear sweep voltametry, a current peak estimated at -3.8 V (vs. Pt-QRE) was observed as a limiting current of neodymium reduction. Potentiostatic electrolysis for 18 hours at room temperature at -6 V (vs. Pt-QRE) confirmed that metallic neodymium was electrodeposited.

• Nuclear Engineering and Technology
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• v.53 no.10
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• pp.3367-3378
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• 2021

The design phase and safety assessment of Generation IV liquid metal-cooled fast reactors calls for the improvement of fuel pin performance codes, in particular the enhancement of their predictive capabilities towards uranium-plutonium mixed oxide fuels and stainless-steel cladding under irradiation in fast reactor environments. To this end, the current capabilities of fuel performance codes must be critically assessed against experimental data from available irradiation experiments. This work is devoted to the assessment of three European fuel performance codes, namely GERMINAL, MACROS and TRANSURANUS, against the irradiation of two fuel pins selected from the SUPERFACT-1 experimental campaign. The pins are characterized by a low enrichment (~ 2 wt.%) of minor actinides (neptunium and americium) in the fuel, and by plutonium content and cladding material in line with design choices envisaged for liquid metal-cooled Generation IV reactor fuels. The predictions of the codes are compared to several experimental measurements, allowing the identification of the current code capabilities in predicting fuel restructuring, cladding deformation, redistribution of actinides and volatile fission products. The integral assessment against experimental data is complemented by a code-to-code benchmark focused on the evolution of quantities of engineering interest over time. The benchmark analysis points out the differences in the code predictions of fuel central temperature, fuel-cladding gap width, cladding outer radius, pin internal pressure and fission gas release and suggests potential modelling development paths towards an improved description of the fuel pin behaviour in fast reactor irradiation conditions.

• Journal of IKEEE
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• v.25 no.3
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• pp.501-505
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• 2021

In this study, we fabricated amorphous indium-tin-gallium-zinc-oxide thin-film transistors (a-ITGZO TFTs) with gate dielectrics of HfO₂ and the mixed layers of HfO₂ and Al₂O₃, and investigated the effect of gate dielectric on electrical characteristics of a-ITGZO TFTs. When only HfO₂ was used as the gate dielectric, the mobility and subthreshold swing (SS) were 32.3 cm²/Vs and 206 mV/dec. For the a-ITGZO TFTs with gate dielectric made of HfO₂ and Al₂O (2:1, 1:1), the mobilities and SS were 26.4 cm²/Vs (2:1), 16.8 cm²/Vs(1:1), 160 mV/dec (2:1) and 173 mV/dec (1:1). On the other hand, the hysteresis window shown in transfer curves of the a-ITGZO TFTs was lessened from 0.60 to 0.09 V by the increase of Al₂O₃ ratio in gate dielectric, indicating that the interface trap density between the gate dielectric and channel layer decreases due to Al₂O₃.

• 한국항공운항학회:학술대회논문집
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• 2007.12a
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• pp.21-22
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• 2007

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2001.06a
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• pp.111-112
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• 2001

• Journal of The Korean Astronomical Society
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• v.6 no.1
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• pp.1-8
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• 1973

Presumable explosion time of Cas A has been listed from Dec. 6, 1592 to Mar. 5, 1593 in ancinet Korean observational records. It may have been overlooked, due to other supernova(Cassiopeia Nova) which appeared at that time near its original position of Cas A.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.57 no.1
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• pp.53-59
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• 2024

The reproductive biology of the Washington clam Saxidomus purpuratus, from Yeosu, Korea was investigated based on 699 individuals collected from January to December 2022. The sex ratio of this species was not significantly different from a 1:1 (male:female) sex ratio (P>0.05). Monthly changes in gonadosomatic index were analyzed to estimate the spawning season. The reproductive cycle of this species can be divided into the following stages: active (Jan.-Mar.), ripe (Mar.-Nov.), spent (Apr.-Dec.), and degenerative (Jun.-Dec.) stages. The spawning period ranged from March to December with the main periods being from April to June and from September to November. The shell length at 50% female group maturity (SL₅₀) was estimated to be 60.2 mm.

• Korean Journal of Plant Resources
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• v.14 no.1
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• pp.60-64
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• 2001

This study was carried out to investigate effects of sowing dates and method on major agronomic characteristics of Dendropanax morbifera $L_{EV}$. in southern area of Korea. The number of days from sowing to emergence was recognized liner negative correlation between sowing days. Dendropanax morbifera was sowed at seven different dates(from Dec.20 to Feb.20 at 30 days interval, from Mar, 1 to Apr. 15 at 15 days interval) in pot culture. In sowing date at Mar. 15, germination rate and early growth were good in pot. Dendropanax morbifera was sowed at five different dates(from Dec.20 to Apr.15 at 15 days interval) in field culture. In sowing date at Apr.15, germination rate and early growth were good in field culture.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.33 no.2
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• pp.93-98
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• 2020

We investigated the effect of a post-annealing process using ultraviolet (UV) light on the electrical properties of solution-processed InZnO (IZO) thin-film transistors (TFTs). UV light was irradiated on IZO TFTs for different time periods of 0s, 30s, and 90s. We measured transfer and retention stability curves to evaluate the performance of the fabricated TFTs. In addition, we measured height, amplitude, and phase AFM images to analyze changes in the surface and morphology of the devices. AFM measurements were performed by setting the drive amplitude of the cantilever tip to 47.9 mV in tapping mode, then dividing the device surface into 500 nm × 500 nm. In the case of IZO TFT irradiated with UV for 30s, the electron mobility and I_on/I_off ratio were improved, the threshold voltage was reduced by approximately 2 V, and the subthreshold swing also decreased form 1.34 V/dec to 1.11 V/dec.

• Journal of KIISE:Databases
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• v.27 no.1
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• pp.90-100
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• 2000

We propose, in this paper, a new query expansion technique with term reweighting. All terms in the documents feedbacked from a user, excluding stopwords, are selected as candidate terms for query expansion and reweighted using the relevance degree which is calculated from the term-distribution similarity between a candidate term and each term in initial query. The term-distribution similarity of two terms is a measure on how similar their occurrence distributions in relevant documents are. The terms to be actually expanded are selected using the relevance degree and combined with initial query to construct an expanded query. We use KT-set 1.0 and KT-set 2.0 to evaluate performance and compare our method with two methods, one with no relevance feedback and the other with Dec-Hi method which is similar to our method. based on recall and precision.