• Nuclear Engineering and Technology
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• v.35 no.1
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• pp.14-24
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• 2003

This work investigates the effects of Cr$_2$O$_3$ and oxygen potential on grain growth and densification of UO$_2$ pellets. Powder mixtures of UO$_2$ and 0.03-0.4wt% Cr$_2$O$_3$ were pressed and sintered in 3 different gas atmospheres: the $H_2O$-to-H$_2$ ratios were 5$\times$10$^{-4}$ , 1$\times$10$^{-2}$ and 3$\times$10$^{-2}$ In the first gas atmosphere the Cr$_2$O$_3$ contents below 0.2 wt% have an insignificant effect on grain size, but the Cr$_2$O$_3$ contents more than 0.3 wt% promote grain growth in the inner zone of a pellet but not in the outer zone. In both the second and third atmospheres, the grain size increases with the Cr$_2$O$_3$ content. With the same level of Cr$_2$O$_3$ content the grain size is larger in the second atmosphere than in the third. Sintering behavior and developed microstructure are discussed in terms of the reduction of C$r^2$O$^3$ to Cr, the dissolution of C$r^2$O$^3$ in UO$_2$, and liquid phase sintering.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.36S no.9
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• pp.1-8
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• 1999

In this paper, we propose and analyze a concatenated coding scheme for DS/CDMA systems in asynchronous channels. In the concatenated coding, bandwidth efficient $2^{2L-2}$-state ${\frac{L}{L+1}}$-rate 2-MTCM with biorthogonal signal constellation is used for the inner code, and $(2^{L-1},\;{\lceil}\frac{2^{L-1}}{L/2}{\rceil})$ RS code is use for the outer code. It is shown that we can get considerable performance gain over the uncoded system without sacrificing the data transmission rate. The proposed system can be used as a coding scheme for reliable and high speed integrated information services of mobile communication systems.

• Journal of the Korea Convergence Society
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• v.8 no.7
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• pp.237-243
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• 2017

Recently, the Korean government is planning to create ICT-centered clusters that will lead the fourth industrial revolution in the Yangjae-Umyeun area. In order for a cluster to be successful, innovation environments such as support systems and institutions should be appropriately prepared. In this study, we present a hierarchical model of ICT SME support measures after comprehending the support measures for existing SMEs and the factors needed for clustering, and then deriving the priorities of support measures. The questionnaire was distributed to 9 ICT SMEs and R&D experts. A total of 6 copies were collected. The priority of the support measures in this study is expected to be utilized for the successful development of R&CD cluster and the allocation of the support budget.

• The KIPS Transactions:PartD
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• v.9D no.4
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• pp.531-542
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• 2002

As most of metadata have been handled on restricted applications, we need a same metadata in order to represent a same video data. However, these metadata make problems that the same video data should be supported by the same metadata. Therefore, in this paper, we extend the Dublin core elements to support the metadata which can solve the problems. The proposed video data representation is managed by the extended metadata of Doblin core model, by using the information of structure, content and manipulation of video data. The thirteen temporal relationship operators are reduced to the six temporal relationship operators by using a dummy shot temporal transformation relationship. The reduced six temporal relationship operators through excluding reverse temporal relationship not only maintain a consistency of representation between a metadata and a video data, but also transform n-ary temporal relationship to binary relationship on shots. We show that the proposed metadata model can be applied to representing and retrieving on various applications as equivalent as the same structure.

• Proceedings of the KIEE Conference
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• 2003.07b
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• pp.723-725
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• 2003

The result of design and Partial fabrication of a 1 MVA single phase high temperature superconducting(HTS) transformer for power distributions are presented in this paper. The HTS windings are wound as double pancake windings which have advantages of uniform distribution of high voltage over the windings. the rated primary and secondary voltages are 22.9 kV and 6.6 kV respectively. Four HTS tapes are wound in parallel for secondary windings considering the rated currents of the transformer. The HTS windings will be cooled down to 65 K by natural convection of sub-cooled liquid nitrogen using a single-staged GM-cryocooler in order to make the stability of the HTS windings better. The iron core is designed as shell type and isolated from the liquid nitrogen by an FRP cryostat which have a room temperature bore. After the complete fabrication of the total HTS transformer system, performance test of the transformer will be carried out.

• Proceedings of the KIEE Conference
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• 2003.07b
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• pp.1003-1005
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• 2003

In this paper, 3-D nonlinear electromagnetic analysis of a single phase 1MVA 22.9 kV/6.6 kV high temperature superconducting(HTS) transformer with double pancake windings was accomplished. The characteristics of 1MVA HTS transformer such as The efficiency, voltage regulation and % impedance voltage drop were obtained by the 3-D non-linear electromagnetic analysis. And in order to verify the 3-D non-linear electromagnetic analysis of a single phase 1MVA HTS transformer, a 1MVA test transformer with windings made of copper tapes with the same size as BSCCO-2223 HTS tape was manufactured. The energy conservation method to perform the analysis of leakage impedances of both a 1MVA HTS transformer and test transformer was used. The characteristic analysis such as efficiency, voltage regulation and % impedance voltage drop of transformer was performed. And the obtained values of both 1MVA HTS transformer and test transformer were compared.

• Journal of Korea Water Resources Association
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• v.50 no.8
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• pp.513-520
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• 2017

In order to analyze flood damage mitigation effects, it is necessary not only to analyze inundation areas and depth through hydraulic and hydrological analysis but also to estimate flood damages. Flood damages of structure and contents of buildings are generally analyzed according to the flood depth. In this study, we developed and applied flood depth-damage functions for the school buildings based on actual damage data. In addition, the development and modification procedure of flood depth-damage functions for school buildings is presented in this paper, and the developed damage functions are verified by comparing them with the existing method. It is expected that the process of developing and applying flood depth-damage functions presented in this study can be used in the cost benefit analysis of flood damage mitigation measures.

• Biomolecules & Therapeutics
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• v.25 no.3
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• pp.308-314
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• 2017

Urotensin II (UII) is a mitogenic and hypertrophic agent that can induce the proliferation of vascular cells. UII inhibition has been considered as beneficial strategy for atherosclerosis and restenosis. However, currently there is no therapeutics clinically available for atherosclerosis or restenosis. In this study, we evaluated the effects of a newly synthesized UII receptor (UT) antagonist, KR-36996, on the proliferation of SMCs in vitro and neointima formation in vivo in comparison with GSK-1440115, a known potent UT antagonist. In primary human aortic SMCs (HASMCs), UII (50 nM) induced proliferation was significantly inhibited by KR-36996 at 1, 10, and 100 nM which showed greater potency ($IC_{50}$: 3.5 nM) than GSK-1440115 ($IC_{50}$: 82.3 nM). UII-induced proliferation of HASMC cells was inhibited by U0126, an ERK1/2 inhibitor, but not by SP600125 (inhibitor of JNK) or SB202190 (inhibitor of p38 MAPK). UII increased the phosphorylation level of ERK1/2. Such increase was significantly inhibited by KR-36996. UII-induced proliferation was also inhibited by trolox, a scavenger for reactive oxygen species (ROS). UII-induced ROS generation was also decreased by KR-36996 treatment. In a carotid artery ligation mouse model, intimal thickening was dramatically suppressed by oral treatment with KR-36996 (30 mg/kg) which showed better efficacy than GSK-1440115. These results suggest that KR-36996 is a better candidate than GSK-1440115 in preventing vascular proliferation in the pathogenesis of atherosclerosis and restenosis.

• The Journal of Dong Guk Oriental Medicine
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• v.4
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• pp.53-66
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• 1995

After 394 inpatients examined as to the result of combined treatment of Oriental and Western medicine on Dongguk Incheon oriental medicine hospital and Dongincheon Gil hospital from july/21/1994 to june/21/1995 for 11 months, the results were obtained as follows : 1. Distribution of sex ; male 187(47.5%), female 207(52.5%) 2. Distribution of age ; 60-69 years 110(28%), 50-59 years 88(22.3%), 70-79 years 84(21.3%), 40-49 years 39(9.9%), 30-39 years 34(8.6%) and the others 39(9.9%) 3. Distribution of disease ; cardiovascular disease 234(59.5%), musculoskeletal disease 62(15.7%) and the others 98(24.3%) 4. Distribution of consult from Oriental medicine to Western medicine ; internal medicine 373(87.4%), Orthopedic 32(7.5%) and the others 22(5.1%) 5. Distribution of test ; routine laboratory test 364(31.7%), chest X-ray 189(16.5%), LFT 177(15.4%), brain CT 129(11.2%) and the others 290(25.2%) 6. Distribution of Western medicine treatment ; fluid therapy 163(35.5%), antihypertensiv 100(21.8%), antibiotics 53(11.6%), oral hypoglycemic agents and insulin preperations 46(10.1%) and the others 95(20.8%) 7. Distribution of disease of consult from Western medicine to Oriental medicine ; obesity 14(34.2%), liver disease 13(31.7%), lumbago 8(19.5%) and the others 6(14.6%) Distribution of Oriental medicine treatment ; Acupuncture and Moxibustion 25(38.5%), astarvation cure 22(33.8%), Oriental herbs 18(27.7%) 8. Distribution of the admission period ; 1-10 days 148(37.6%), 11-20 days 105(26.6%), 21-30 days 69(17.5%) and the others 72(18.3%).

• Research in Plant Disease
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• v.29 no.3
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• pp.243-250
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• 2023

To explore the distribution and the resistance reaction of rice blast pathogens that may occur in North Korea, rice blast pathogens in the North Korean border regions of Dandong and Yeon-gil in China and the North Korean border region of Cheorwon in South Korea were analyzed. In addition, comparative analysis was conducted with rice blast pathogen in Suwon and Jeonju, inland regions of South Korea. Resistance reactions above average were observed in monogenic rice lines (IRBLzt-T, IRBL9-W, IRBL20-IR24, and IRBLta-CP1) in Jeonju, Suwon, and Cheorwon from 2018 to 2020. In Dandong and Yeon-gil, the monogenic lines IRBLz5-CA, IRBL12-M, and IRBL19-A consistently showed resistance reactions for three years. Notably, IRBL19-A exhibited strong resistance. Race distribution analysis in South Korea indicated a shift from KI to KJ dominance from 2018 to 2020, while in the North Korean border regions of Dandong and Yeon-gil, the KI race was dominant in 2021 and 2022. The race distribution of rice blast pathogens in China's North Korean border regions differed significantly from that in South Korea.