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Jiyoung Yi;Chang-Lak Kim
- Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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- v.21 no.3
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- pp.347-357
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- 2023
United States Nuclear Regulatory Commission (U.S. NRC) specifies regulations on obtaining licenses and describes the technical position on the average waste concentration, also known as Concentration Averaging and Encapsulation Branch Technical Position (CA BTP); CA BTP helps classify blendable waste and discrete items and address concentration averaging. The technical position details are reviewed and compared in a real environment in Korea. A few cases of concentration averaging based on the application of CA BTP to domestic radioactive waste are presented, and the feasibility of the application is assessed. The radioactive waste considered herein does not satisfy the Disposal Concentration Limit (DCL) of the second-phase disposal facility while applying the preliminary classification. However, if CA BTP is applied when the radioactive waste is mixed with other radioactive waste items in a large and heavy container, it can be disposed of at the second-phase disposal facility in Gyeongju Repository. To apply the CA BTP of the U.S. NRC, it is necessary to investigate the safety assessment conditions of the US and Korea.
https://doi.org/10.7733/jnfcwt.2023.024 인용 PDF

Jung, Tae-Woong;Moon, Su-Jung;Kim, Yoon-Kwan;Koo, Jee-Hee
- Spatial Information Research
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- v.20 no.1
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- pp.19-26
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- 2012
Since $CO_2$ emissions are recognized as the biggest contribution to climate change, the needs and international efforts for $CO_2$ emissions reduction are increasing. The developed countries are driving strategies to boost green industry as a new growth engine. Following this global trend, based on the ongoing U-City project as a new city model, it is required to analyze the changes of $CO_2$ emissions in U-City to identify its potential for reducing carbon dioxide emissions. This study aims at identifying the potential and effects on $CO_2$ reduction by analyzing the level of $CO_2$ emissions before and after introducing U-City. Bundang-Gu, Seongnam-City & Ilsan-Gu, Goyang-City among Phase I new tow ns were selected as model cities before introducing U-City and Dongtan-Dong, Hwaseong-City as a model city after introducing U-City. The result showed 30% reduction of $CO_2$ emissions in the comparison of tw o models.
https://doi.org/10.12672/ksis.2012.20.1.019 인용 PDF KSCI

Park, Min-Su;Lee, Hwa-Seong;An, Byeong-Tae
- Korean Journal of Materials Research
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- v.5 no.5
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- pp.583-597
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- 1995
We investigated the effect of the oxygne partial pressure on the phase stability of B $i_{2}$S $r_{2}$Ca C $u_{2}$ $O_{8+x}$ and B $i_{2}$S $r_{2}$C $a_{2}$C $u_{3}$ $O_{10+x}$ at 82$0^{\circ}C$. As the oxygen pressure decreased, B $i_{2}$Sr/sb 2/CaC $u_{2}$ $O_{8+x}$ melted at 2.2$\times$10$^{-3}$ atm $O_{2}$. In the case of the B $i_{1.7}$P $b_{0.4}$S $r_{2}$C $a_{2}$ $O_{10+x}$, it started to decompose into theree phases of B $i_{2}$S $r_{2}$Cu $O_{6+y}$, $Ca_{2}$Cu $O_{3}$ and C $u_{4}$ $O_{3}$ and C $u_{4}$ $O_{3}$ at 8.0$\times$10$^{-3}$ atm $O_{2}$ and was completely decomposed at 4.3$\times$10$^{-3}$ atm $O_{2}$ B $i_{2}$S $r_{2}$C $a_{2}$C $u_{3}$ $O_{10+x}$ phase was not formed by the solid state reaction from the mixutre of $i_{2}$S $r_{2}$CaCu.sub 2/ $O_{8+x}$, $Ca_{2}$Cu $O_{3}$ and CuO down to 2.2$\times$10.sub -3/ atm O.sub 2/ but formed by the solidifciation of the formed from the mixture of the intermediate compounds in the Bi-Sr-Ca-Cu-O system and the fromation temperature of Bi.sub 2/S $r_{2}$C $a_{2}$Cu.$_{3}$ $O_{10+x}$ can be lowered by reducing oxygen partial pressure.e.e.ure.e.e.
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Park, Y.P.;Wang, J.B.;Kim, H.C.;Kim, W.G.;Lee, J.U.
- Proceedings of the KIEE Conference
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- 1991.11a
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- pp.311-315
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- 1991
The formation and transition of 2212 and 2223 phase have been studied in BPSCCO system. The 2212 phase formed in early sintering state reacts on $Ca_2PbO_4,\;Ca_2CuO_3$ and CuO during sintering process and thus produces the 2223 phase. A long sintering period is need to fabricate the superconductor with large volume fraction of 2223 phase. Also, the thin plate-like grains composed of Bi, Sr, Ca and Cu contribute to 2223 phase formation. Though the sample has lower volume fraction of 2223 phase, the critical temperature is measured highly in case of the grain grown to plate-like shape. In this work, the critical temperature of the sample sintered for 264 hr in air was measured 108 K. Microstructure of the sample was varied with condition of heat treatment after sintering process and the sample annealed with $500^{\circ}C$ for 5 hr showed excellent charateristics of 2223 phase formation.
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