• Nuclear Engineering and Technology
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• 제50권5호
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• pp.794-800
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• 2018

The proliferation resistance (PR) of Th/U and Th/Pu fuels used in CANada Deuterium Uranium for the deep geological repository was assessed by combining the multiattribute utility analysis proposed by Chirayath et al., 2015 with the transport model of radionuclides in the repository and comparing with that of the used natural U fuel case. It was found that there was no significant advantage for Th/U and Th/Pu fuels from the viewpoint of the PR in the repository. It was also found that the PR values for used nuclear fuels in the repository of Th/U, Th/Pu, and natural U was comparable with those for enrichment and reprocessing facilities in the pressurized water reactor (PWR) nuclear fuel cycle. On the other hand, the PR values considering the transport of radionuclides in the repository were found to be slightly smaller than those without their transport after the used nuclear fuels started dissolving after 1,000 years.

• Nuclear Engineering and Technology
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• 제54권7호
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• pp.2660-2669
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• 2022

The attractiveness for weapons usage of the proposed fuel cycle for the PT-SCWR was evaluated in this study using the Figure-of-Merit methodology. It was compared to the attractiveness of other fuel cycles namely, Low Enriched Uranium (LEU), U/Th, Re-enriched Reprocessed Uranium (RepU), and Pu/Th/U. The optimal content of natural uranium, which can be added to Pu/Th to render the produced U-233 unattractive, was found to be 9%. A ranking system to compare the attractiveness of the various fuel cycles is proposed. RepU was found to be the most proliferation resistant fuel cycle for the first 100 years,while, the least proliferation resistant fuel cycle was the originally proposed Pu/Th one. The reactivity feedback coefficients were calculated for all proposed fuel cycles. All studied reactivity coefficients have the same sign implying that all the fuel cycles will behave neutronically in a similar way. The Pu/Th/U fuel was found to have the most negative value of the Coolant Void Reactivity which will help to restore the core to a safe status faster in case of a loss-of-coolant accident. The fuel and moderator temperature coefficients did not show significant differences between the fuels studied.

• Nuclear Engineering and Technology
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• 제54권1호
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• pp.30-35
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• 2022

In a nuclear reactor, gamma radiation is the dominant energy deposition in non-fuel regions. Heat is generated upon gamma deposition and consequently affects the mechanical and thermal structure of the material. Therefore, the safety of samples should be carefully considered so that their integrity and quality can be retained. To evaluate relevant parameters, an in-core gamma thermometer (GT) was used to measure gamma heating (GH) throughout the operation of the McMaster nuclear reactor (MNR) at four irradiation sites. Additionally, a Monte Carlo reactor physics code (Serpent-2) was utilized to model the MNR with the GT located in the same irradiation sites used in the measurement to verify its predictions against measured GH. This research aids in the development of modeling, calculation, and prediction of the GH utilizing Serpent-2 as well as implementing a new GH measurement at the MNR core. After all uncertainties were quantified for both approaches, comparable GH profiles were observed between the measurements and calculations. In addition, the GH values found in the four sites represent a strong level of radiation based on the distance of the sample from the core. In this study, the maximum and minimum GH values were found at 0.32 ± 0.05 W/g and 0.15 ± 0.02 W/g, respectively, corresponding to 320 Sv/s and 150 Sv/s. These values are crucial to be considered whenever sample is planned to be irradiated inside the MNR core.

• Nuclear Engineering and Technology
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• 제54권5호
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• pp.1616-1622
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• 2022

Selenium has been identified as an element of interest for the safety assessment of a deep geological repository (DGR) for used nuclear fuel. In Canada, groundwaters at DGR depths in sedimentary rocks have been observed to have a high ionic strength. This paper examines the sorption behavior of Se(-II) onto illite, MX-80 bentonite, Queenston shale, and argillaceous limestone in Na-Ca-Cl solutions of varying ionic strength (0.1-6 mol/kgw (m)) and across a pH range of 4-9. Little ionic strength dependence for Se(-II) sorption onto all solids was observed except that sorption at high ionic strength (6 m) was generally slightly lower than sorption at low ionic strength (0.1 m). Illite and MX-80 exhibited the expected results for anion sorption, while shale and limestone exhibited more constant sorption across the pH range tested. A non-electrostatic surface complexation model successfully predicted sorption of Se(-II) onto illite and MX-80 using the formation of an inner-sphere surface complex and an outer-sphere surface complex. Optimized values for the formation reactions of these surface species were proposed.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2018년도 추계학술대회
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• pp.109-110
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• 2018

ITER 토카막의 초전도코일에 전원을 공급하는 Plant는 CCPS (Correction Coil Power Supply System), TFPS(Toroidal Field Power Supply System), PFCS(Poloidal Field & Central Solenoid)으로 구성되어 있다. 각 Plant의 AC/DC 컨버터는 초전도 코일에 막대한 전류를 흘려 토카막 내에서 1억도에 달하는 열과 전자장의 압력으로 플라즈마상태의 수소를 결합시켜 핵융합에 도달하도록 한다. MCS(Master Control System)은 플라즈마가 핵융합을 잘 구현할 수 있도록 초전도 코일에 공급하는 전원을 총괄적으로 제어한다. 특히 PFCS MCS는 토카막 장치에서 다른 Plant와의 Interface가 복잡하여 설계 및 제작에 어려움이 많다. 본 논문에서는 PFCS MCS가 ITER의 설계요건과 국제기술기준에 맞게 설계하고, 제작하였는지를 확인하기 위해 공장에서 최종 검사하는 FAT(Factory Acceptance Test) 절차를 소개하고 여러 가지 시험을 통하여 평가한 내용을 보이고자 한다.

• Kyungpook Mathematical Journal
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• 제9권1_2호
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• pp.71-75
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• 1969

• 한국수학사학회:학술대회논문집
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• 한국수학사학회 1997년도 가을학술발표회 논문초록집
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• pp.3-3
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• 1997

• Kyungpook Mathematical Journal
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• 제27권2호
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• pp.109-114
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• 1987

• Kyungpook Mathematical Journal
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• 제23권2호
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• pp.147-154
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• 1983

• Kyungpook Mathematical Journal
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• 제22권2호
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• pp.151-160
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• 1982