• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.256-260
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• 2003

The paper is aiming at presenting the proper treatment method and procedures of ILW waste to both waste generators and acceptor so that the waste characteristics are satisfied with the WAC(Waste Acceptance Criteria) and as a result, the disposal facility would be operating safely. The ILW generators are responsible for reducing the volume of waste, treating and packaging the waste in order to meet the WAC, and acceptor has an obligation of inspecting the waste in conformity with the acceptance procedure established by regulation. Recently, a number of countries including France and USA examine the disposal acceptability of ILW waste by the WCP(Waste Package Quality Certification Program).

• Macromolecular Research
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• v.16 no.8
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• pp.734-740
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• 2008

A new crosslinked, poly(acrylic acid)-based, dehydrating agent was synthesized through solution polymerization. The Taguchi method, a robust experimental design, was adopted to optimize the synthetic conditions based on the moisture and water absorbing capacities of the dehydrating agent. The method applied for the experiment was a standard L27 ($3^8$) orthogonal array with eight parameters and three levels. By analyzing the variance of the test results, the most effective parameters to control the moisture absorbing capacity (MAC) and its rate were the kind of alkaline base (LiOH, NaOH, or KOH) used as a neutralizing agent of the acrylic acid monomer and the degree of neutralization: The maximum MAC of 40% was achieved at only 2 hat $32^{\circ}C$ and 50% RH when KOH was used as a base and the degree of neutralization was 90%, respectively. However, the water absorbing capacity (WAC) of the resulting dehydrating agent was very low at 158 g/g, indicating that WAC is unaffected by MAC and its rate in this system. The surface morphologies of the agents were examined using scanning electron microscopy (SEM).

• Nuclear Engineering and Technology
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• v.54 no.9
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• pp.3235-3241
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• 2022

The Korea Atomic Energy Research Institute (KAERI) is planning the construction of the KIJANG Research Reactor (KJRR) for stable supply of ⁹⁹Mo. The Fission ⁹⁹Mo Production Process (FMPP) of KJRR produces solid waste such as spent uranium cake and alumina cake, and liquid waste in the form of intermediate level liquid waste (ILLW) and low level liquid waste (LLLW). This study thus established the operating range and optimum operating conditions for the cementation of ILLW from FMPP. It also evaluated whether cement waste form samples produced under optimum operational conditions satisfy the waste acceptance criteria (WAC) of a disposal facility in Korea (Korea radioactive waste agency, KORAD). Considering economic feasibility and safety, optimum operational conditions were achieved at a w/c ratio of 0.55, and the corresponding salt content was 5.71 wt%. The cement waste form samples prepared under optimum operational conditions were found to satisfy KORAD's WAC when tested for structural stability and leachability. The results indicate that the proposed cementation conditions for the disposal of ILLW from FMMP can be effectively applied to KJRR's disposal facility.

• Nuclear Engineering and Technology
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• v.53 no.7
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• pp.2261-2267
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• 2021

This paper evaluates the efficacy of magnesium potassium phosphate cements (MKPCs) as waste forms for the solidification of radioactive concrete powder wastes produced by the decommissioning of nuclear power plants. MKPC specimens that contained up to 50 wt% of simulated concrete powder wastes (SCPWs) were evaluated. We measured the porosity and compressive strength of the MKPC specimens, observing them using scanning electron microscopy and X-ray diffraction. The addition of SCPWs reduced the porosity and increased the compressive strength of the MKPC specimens. Struvite-K crystals were well-synthesized, and no additional crystal phase was formed. After thermal cycling and after immersion, MKPC specimens with 50 wt% SCPWs satisfied the waste-acceptance criteria (WAC) for compressive strength. Semi-dynamic leaching tests were performed using the ANS 16.1 method; the leachability indices of Cs, Co, and Sr were 11.45, 17.63, and 15.66, respectively, which also satisfy the WAC. Thus, MKPCs can provide stable matrices to immobilize radioactive concrete wastes generated by the decommissioning of nuclear power plants.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2005.11a
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• pp.126-133
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• 2005

Securing of radioactive waste disposal site and the related operations for disposal of low and intermediate level radioactive waste is being actively carried out in Korea. For disposal of radioactive wastes, physicochemical and radiological status and integrity of radioactive wastes must be secured first. Also, waste generators must provide this information to disposers. In addition, to secure the safety of waste disposal, waste acceptance criteria (WAC) and site specific waste acceptance criteria (SWAC) to consider characteristics of the disposal site are required. Radioactive wastes must be processed, generated, managed and transferred in accordance with these criteria. [1] For this, evaluation of properties on each of the radioactive wastes must be performed. However, in reality, atomic power plants are experiencing difficulties in relation to this due to the large quantity of radioactive waste generation. In order to solve this problem, IAEA and major overseas countries have developed, thus are using waste certification program (WCP) and quality assurance program (QAP) [2,3]. On the basis of these programs, radioactive waste certification program has been developed for safe disposal of radioactive wastes in Korea to satisfy the provisions specified in 'low and intermediate level radioactive waste transfer guidelines' of announcement No. 2005-18 from the Ministry of Science and Technology and specific site waste acceptance criteria (tentative plan). In addition, it is being planned to administer amendment on commercial atomic power plant related procedures and ensile staff training in order for early introduction and operation of radioactive waste certification system.

• Horticultural Science & Technology
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• v.16 no.2
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• pp.222-225
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• 1998

The objective of this study was to observe the effects of potassium-carboxymethyl cellulose (K-CMC), which is a natural polymer derivative, and polyacrylamide (PAM), which is a commercial synthetic polymer, on soil physicochemical properties and yields of the cabbage. To increase water absorbing capacity (WAC), hydrophilic carboxymethyl group was introduced to cellulose chain and it was confirmed by FT-IR. WAC was tested by tea-bag method in distilled water and 3% NaCl solution. PAM is slightly more absorptive than K-CMC in distilled water, but in NaCl solution, K-CMC is more absorptive than PAM. Soil particle sizes above $1_{mm}$ were immediately increased from 9.6 to approximately 16.6% by the application of K-CMC and PAM, respectively. Infiltration rates of soil were approximately twice as great as those of the control when conditioned with the K-CMC and PAM treatment. K content of soil treated with K-CMC was significantly higher than those of PAM and control, but the other components of soil chemical properties were not different. The early growth and vegetative production of cabbage in the K-CMC and PAM treatments were significantly higher than the control. The contents of vitamin C were increased with the treatment of K-CMC. It was proposed that K-CMC treatment influence K component of the soil and vitamin C content of the cabbage, therefore, it improved the yields as well as crop quality.

• Journal of the Korean Applied Science and Technology
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• v.31 no.3
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• pp.500-508
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• 2014

For this research, synthesis acrylic resin by ethyl acrylate monomer(EAM) and prepared samples which set by difference amount of monoammonium phosphate solution in waterborne acrylic resin. Use these resins, analyzed mechanical properties and thermal stability by films and leather surface coated. The test of DSC experiment sample WAC-APS3 was $410^{\circ}C$ Tm values which means the highest content of monoammonium phosphate had highest thermal stability in acrylic resin. According to measure data for solvent resistance, all samples showed good property. As known in the results, increase of ammonium phosphate constant did not influence to big change of resin properties. In abrasion test WAC-APS3 was good abrasion properties(68.729 mg.loss). Test of tensile strength, as increase as monoammonium phosphate resin analyzed low properties $1.505kgf/mm^2$ to $1.275kgf/mm^2$. In elongation case, same as strength test result 425 % to 384 % by increase to monoammonium phosphate amount in acrylic resin.

• The Pure and Applied Mathematics
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• v.13 no.4 s.34
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• pp.249-254
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• 2006

Category Fuz of fuzzy sets has a similar function to the topos Set. But Category Fuz forms a weak topos. We show that supports split weakly(SSW) and with some properties, implicity axiom of choice(IAC) holds in weak topos Fuz. So weak axiom of choice(WAC) holds in weak topos Fuz. Also we show that weak extensionality principle for arrow holds in weak topos Fuz.

• Proceedings of the Korean Society for Information Management Conference
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• 2001.08a
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• pp.167-172
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• 2001

클러스터링 성능 평가를 위한 척도로 여러 공식이 개발되어 사용되어왔다. 이들 평가척도는 가급적 범위가 제한되며, 가환성이 있고, 비편향적이며 단일 척도일 필요가 있다. 기존 평가 척도에 대해서 검토한 후 비편향적인 단일 척도 WACS를 개발하였다. 클러스터 수를 달리하는 클러스터링 결과에 대해 여러 평가척도를 적용해서 성능을 평가하는 실험을 통해서 WACS 척도가 평가척도로서의 요건을 만족시킨다는 것을 확인하였다.

• Korean Journal of Pharmacognosy
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• v.49 no.1
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• pp.47-54
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• 2018

Astilbe rubra (AR) is a perennial, belongs to the Saxifragaceae family, it contains tannin and triterpene. AR has been used in republic korea to improve toxication, fever, pain and convulsion. Recently, number of natural products have been analyzed for potential pharmacological activities including anti-cancer, anti-obesity and anti-diabetic medication. Consequently, we investigated the growth inhibition effect of Astilbe rubra water extract (WAC), ethanol extract (EAC) and bergenin on Hela cell (human adenocarcinoma cell). From whole plant of A. rubra, bergenin was isolated by column chromatography and its structures were identified by $^1H$, $^{13}C$ NMR and IT TOF-ESI MS. High extraction efficiency of bergenin was shown at 0.95% under 60 min reflux extraction with 50% MeOH. The MTS assay showed that EAC (ethanol extract) treatment increased cell death in a dose-dependent manner. Moreover, EAC treatment on Hela cell increased apoptotic cell death and caspase-3 activity. Results suggest that EAC has growth inhibition effect on Hela cells, but not WAC and bergenin. $500{\mu}g/mL$ EAC treatment inhibited Hela cell at $60.2{\pm}1.5%$.