• Proceedings of the Optical Society of Korea Conference
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• 2007.02a
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• pp.321-322
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• 2007

• Proceedings of the Korean Nuclear Society Conference
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• 2005.05a
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• pp.1034-1035
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• 2005

• Proceedings of the Korean Nuclear Society Conference
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• 2003.10a
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• pp.246.1-246.1
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• 2003

• Nuclear Engineering and Technology
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• v.48 no.1
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• pp.55-63
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• 2016

Calculation of the core neutronic parameters is one of the key components in all nuclear reactors. In this research, the energy spectrum and spatial distribution of the neutron flux in a uranium target have been calculated. In addition, sensitivity of the core neutronic parameters in accelerator-driven subcritical advanced liquid metal reactors, such as electron beam energy ($E_e$) and source multiplication coefficient ($k_s$), has been investigated. A Monte Carlo code (MCNPX_2.6) has been used to calculate neutronic parameters such as effective multiplication coefficient ($k_{eff}$), net neutron multiplication (M), neutron yield ($Y_{n/e}$), energy constant gain ($G_0$), energy gain (G), importance of neutron source (${\varphi}^*$), axial and radial distributions of neutron flux, and power peaking factor ($P_{max}/P_{ave}$) in two axial and radial directions of the reactor core for four fuel loading patterns. According to the results, safety margin and accelerator current ($I_e$) have been decreased in the highest case of $k_s$, but G and ${\varphi}^*$ have increased by 88.9% and 21.6%, respectively. In addition, for LP1 loading pattern, with increasing $E_e$ from 100 MeV up to 1 GeV, $Y_{n/e}$ and G improved by 91.09% and 10.21%, and $I_e$ and $P_{acc}$ decreased by 91.05% and 10.57%, respectively. The results indicate that placement of the Np-Pu assemblies on the periphery allows for a consistent $k_{eff}$ because the Np-Pu assemblies experience less burn-up.

• Journal of radiological science and technology
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• v.22 no.2
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• pp.53-56
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• 1999

A Gaussian distribution was parametrized for the initial distribution of the electron beam emitted from a 6MeV medical linear accelerator. A percent depth dose was measured in a water phantom and the corresponding Monte Carlo calculations were performed starting from a Gaussian distribution for a range of standard deviations, ${\sigma}=0.1$, 0.15, 0.2, 0.25, and 0.3 with being the mean value for the Incident beam energy. When measurement and calculation were compared, the calculation with the Gaussian distribution for ${\sigma}=0.25$ turned out to agree best with the measurement. The results from the present work can be utilized as input energy data in planning an electron beam therapy with a Monte Carlo calculation.

• Journal of Powder Materials
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• v.15 no.6
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• pp.466-470
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• 2008

Experiments with a URT-0.5 accelerator (0.5 MeV, 50 ns, 1 kW) generating a nanosecond electron beam for irradiation of silver nitrate in various liquid solutions (water and toluene) were performed with the aim of producing silver nanopowders. A radiochemical reaction allows making weakly agglomerated pure Ag powders with particles of 10-15 nm and 30-50 nm in size by irradiation in toluene and water respectively. The injection of the nanosecond electron beam energy to the solution is optimal. As the absorbed dose increases, the output of the radiochemical reaction does not grow, but more agglomerated powders are synthesized.

• The Journal of Korean Society for Radiation Therapy
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• v.20 no.2
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• pp.123-130
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• 2008

Purpose: To provide practical education, most universities should be equipped with medical appliances in need. As compensatory measures, Gimcheon College has produced in-house dummy linac and dummy accessories, we are going to report efficiency and its usage. Materials and Methods: Dummy linear accelerator (DLINAC-001) has the same mechanical functions as rotation of gantry and collimation in linear accelerator. In addition, to maximize practical education, we have produced and utilized in-house custom blocks, wedge filters, electron cones and head rests. Results: The in-house produced linear accelerator with the same mechanical functions as the linear accelerator, DLINAC-001 can be effectively used in practicing diverse medical instruments. Conclusion: We have produced dummy linear accelerators and dummy accessories and utilized them in practice classes, which can provide the students with clinical training in diverse fields. Consequently, the students exposed to the maximized educational effectiveness can be easily equipped with the practical competence required in real clinical fields.

• Journal of Ginseng Research
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• v.22 no.4
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• pp.252-259
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• 1998

Electron beam, electrically produced from an electron accelerator, was compared with gamma energy in terms of its influence on color and organoleptic qualities of ginseng powders when exposed to the energy used for their microbial decontamination. Hunter color L and b values were suitable for measuring color characteristics of ginseng powders, which were not significantly changed by the exposure to 5 to 7.5 kGy electron beam and gamma energy. Fifty percent ethanol extracts of irradiated ginseng powders at 10 key showed negligible differences from the non-irradiated control in the pattern of absorption spectra at 280∼800 am, but showed increased values in overall color difference (AE) as compared with powdered samples. Irradiation more than 10 kGy and storage at ambient temperature for 4 months caused browning of powdered samples. Irradiation at more than 10 kGy of electron beam was found a critical level to bring about appreciable changes (p<0.05) in or-ganoleptic qualities such as color and odor of sterilized samples, and red ginseng powder was more susceptible than white one to organoleptic changes by irradiation.

• Journal of Magnetics
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• v.19 no.1
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• pp.15-19
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• 2014

In this study, for 6-20 MeV electron beam energy occurring in a linear accelerator, the authors attempted to investigate the relation between the effective source-skin distance and the relation between the radiation field and the effective source-skin distance. The equipment used included a 6-20 MeV electron beam from a linear accelerator, and the distance was measured by a ionization chamber targeting the solid phantom. The measurement method for the effective source-skin distance according to the size of the radiation field changes the source-skin distance (100, 105, 110, 115 cm) for the electron beam energy (6, 9, 12, 16, 20 MeV). The effective source-skin distance was measured using the method proposed by Faiz Khan, measuring the dose according to each radiation field ($6{\times}6$, $10{\times}10$, $15{\times}150$, $20{\times}20cm^2$) at the maximum dose depth (1.3, 2.05, 2.7, 2.45, 1.8 cm, respectively) of each energy. In addition, the effective source-skin distance when cut-out blocks ($6{\times}6$, $10{\times}10$, $15{\times}15cm^2$) were used and the effective source-skin distance when they were not used, was measured and compared. The research results showed that the effective source-skin distance was increased according to the increase of the radiation field at the same amount of energy. In addition, the minimum distance was 60.4 cm when the 6 MeV electron beams were used with $6{\times}6$ cut-out blocks and the maximum distance was 87.2 cm when the 6 MeV electron beams were used with $20{\times}20$ cut-out blocks; thus, the largest difference between both of these was 26.8 cm. When comparing the before and after the using the $6{\times}6$ cut-out block, the difference between both was 8.2 cm in 6 MeV electron beam energy and was 2.1 cm in 20 MeV. Thus, the results showed that the difference was reduced according to an increase in the energy. In addition, in the comparative experiments performed by changing the size of the cut-out block at 6 MeV, the results showed that the source-skin distance was 8.2 cm when the size of the cut-out block was $6{\times}6$, 2.5 cm when the size of the cut-out block was $10{\times}10$, and 21.4 cm when the size of the cut-out block $15{\times}15$. In conclusion, it is recommended that the actual measurement is used for each energy and radiation field in the clinical dose measurement and for the measurement of the effective source-skin distance using cut-out blocks.

• Proceedings of the KIEE Conference
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• 1996.11a
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• pp.193-195
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• 1996

Low-density polyethylene(LDPE ; thickness 100[${\mu}m$] as a experimental specimen is irradiated with electron beam by using electron beam accelerator, and as an experimental specimen, the nonirradiated specimen and the specimen irradiated with electron beam is produced according to the classification of dose. From the analysis of DSC, the crystalline melting point of the specimen irradiated with electron beam is lower than that of virgin specimen. It is confirmed thai the volume resistivity is increased from the temperature over $50[^{\circ}C]{\sim}60[^{\circ}C]$ to the crystalline melting point because of the defects of solid structure and the formation of many trap centers by means of electron beam irradiation, but decreased in the temperature over the crystalline melting point because of the melt of crystalline.