• Nuclear Engineering and Technology
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• v.56 no.6
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• pp.1943-1949
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• 2024

This study focuses on the comparative analysis of ABS polymer samples produced using two distinct manufacturing techniques: 3D printing and the sol-gel methods. In the first approach, ABS polymer was augmented with rare earth oxides, Er₂O₃ and Gd₂O₃, in nano powder form and fabricated into test specimens using 3D printing technology. In the second approach, identical samples were prepared via the sol-gel technique involving mold-based fabrication. Elemental content analysis revealed no significant differences between the samples produced by the two methods. The study proceeds to evaluate the gamma-ray shielding, neutron shielding, temperature resistance, and SEM/EDS pictures of ABS samples generated through both techniques. 3D printing method exhibited more favorable results in terms of structure morphology and thermal stability while there is no significant difference for radiation shielding. The results provide insights into the performance and suitability of each production method for radiation shielding applications. This research not only contributes to enhancing radiation shielding technology but also informs the selection of the most appropriate fabrication method for specific applications in nuclear technologies and diagnostic energy range in medical purposes.

• Proceedings of the Korean Nuclear Society Conference
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• 2005.05a
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• pp.966-967
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• 2005

• Proceedings of the Korean Nuclear Society Conference
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• 2005.05a
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• pp.1012-1013
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• 2005

• Proceedings of the Korean Nuclear Society Conference
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• 2005.10a
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• pp.811-812
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• 2005

• Journal of Radiation Protection and Research
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• v.30 no.4
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• pp.167-174
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• 2005

The concentrations of natural and artificial radionuclides in soil and gamma ray dose rate in air at 233 locations in Korea have been determined. The national mean concentrations of $^{232}Th,\;^{226}Ra,\;^{40}K,\;^{137}Cs\;and\;^{90}Sr$ in soil were $60{\pm}31,\;33{\pm}14,\;673{\pm}238,\;35{\pm}9.3\;and\;5.0{\pm}3.4\;Bq\;kg^{-1}$, respectively. The mean gamma-ray dose rate at 1 m above the ground was $7918\;nGy\;h^{-1}$. $^{137}Cs$ concentration had highly significant correlation with organic matter content and cation exchange capacity. $^{90}Sr$ concentration had slightly coherent with pH. The results have been compared with other global radioactivity and radiation measurements.

• Journal of Radiation Protection and Research
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• v.26 no.3
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• pp.155-159
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• 2001

Beta radiation is measured for an environmental monitoring purpose or for an internal radiation exposure monitoring of nuclear power plant's worker. In korea, strontium 89 and strontium 90 is measured for an environmental monitoring purpose. Also tritium and carbon 14 contained in urine is measured for an internal radiation exposure monitoring of nuclear power plant's worker. Because above isotopes emits low energy beta radiations having a wide range of energy, very complicated isotope separation preprocess is needed. In this study, two mixed beta emitting isotopes are measured simultaneously using a liquid scintillation counter(LSC) and analyzed by using a developed statistical method. Banded least square method is used to analyze the mixed spectrum, and the goodness-of-fitness test is proposed. Test results show that the developed procedure can be very useful for analyzing a mixed beta emitting isotopes.

• Journal of Radiation Protection and Research
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• v.41 no.4
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• pp.384-388
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• 2016

Background: For a verification of newly-developed neutron absorbers, one of guidelines on the qualification and acceptance of neutron absorbers is the neutron attenuation test. However, this approach can cause a problem for the qualifications that it cannot distinguish how the neutron attenuates from materials. Materials and Methods: In this study, an estimation method of neutron absorption performances for materials is proposed to detect both direct penetration and back-scattering neutrons. For the verification of the proposed method, MCNP simulations with the experimental system designed in this study were pursued using the polyethylene, iron, normal glass and the vitrified form. Results and Discussion: The results show that it can easily test neutron absorption ability using single absorber model. Also, from simulation results of single absorber and double absorbers model, it is verified that the proposed method can evaluate not only the direct thermal neutrons passing through materials, but also the scattered neutrons reflected to the materials. Therefore, the neutron absorption performances can be accurately estimated using the proposed method comparing with the conventional neutron attenuation test. Conclusion: It is expected that the proposed method can contribute to increase the reliability of the performance of neutron absorbers.

• Journal of the Korean Society of Radiology
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• v.11 no.6
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• pp.483-491
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• 2017

This study investigates the perception of the general public through analysis of various potential risk factors reflecting nuclear power generation and nuclear power (radiation) and risks. A total of 293 copies of the data were collected from various strata in Busan. As a result, among the potential factors in everyday life, there was a high awareness of the risk to the fire. Next, the perception of risk for radiation terror and nuclear (nuclear) energy was relatively high compared to other risk factors. In the analysis according to age, educational background, and political ideological tendency, the results were contradictory to the necessity, risk and safety of nuclear power generation. The potential risk factors and the perception of nuclear power according to the tendency of political ideology were analyzed to be positive recognition of conservative ideology and negative recognition of progressive group. In other words, the perception of nuclear power was analyzed differently according to the tendency of political ideology. Therefore, it should be decided to reflect the opinions of experts and various opinions of the general public in the setting of nuclear radiation (radiation), it is believed that ordinary people need to take flexible action without having a vague sense of anxiety about various potential risks and nuclear power (radiation) based on objective and scientific grounds.

• Nuclear Engineering and Technology
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• v.52 no.8
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• pp.1706-1713
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• 2020

Functionally gradient material (FGM) is promisingly effective in mitigating the thermal stress between plasma facing materials (PFM) and structural materials. However, the corresponding research with respect to W/V FGM has not been reported yet. In this work, we firstly report the successful fabrication of W/V FGM by a combined technology of mechanical alloying (MA) and spark plasma sintering (SPS). The microhardness and microstructure of the consolidated sample were both investigated. W/V stacks show significantly enhanced microhardness (>100%) compared with pure W plate, which is beneficial to the integral strength of the hybrid structure. Furthermore, we clarify that the different ductility of W and V should be carefully considered, otherwise W/V powder might aggregate and lead to the formation of compositional segregation, and simultaneously unmask the impact of V proportion on the distribution of second phase in W-V binary alloy system. This work provides an innovative approach for obtaining W-V connections with much better performance.

• Nuclear Engineering and Technology
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• v.51 no.1
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• pp.190-197
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• 2019

W-K-TiC alloys with different titanium carbide concentrations (0.05, 0.1, 0.25, 0.5, 1, 2) wt.% were fabricated through Mechanical Alloying and Spark Plasma Sintering. The effects of the addition of nano-scaled TiC particles on the relative density, Vickers micro-hardness, microstructure, crystal information, thermal shock resistance, and tensile strength were investigated. It is revealed that the doped TiC nano-particles located at the grain boundaries. The relative density and Vickers micro-hardness of W-K-TiC alloys was enhanced with TiC addition and the highest Vickers micro-hardness is 731.55. As the TiC addition increased from 0.05 to 2 wt%, the room-temperature tensile strength raised from 141 to 353 MPa. The grain size of the W-K-TiC alloys decreased sharply from $2.56{\mu}m$ to 330 nm with the enhanced TiC doping. The resistance to thermal shock damage of W-K-TiC alloys was improved slightly with the increased TiC addition.