• Proceedings of the SAREK Conference
• /
• 2006.06a
• /
• pp.596-601
• /
• 2006

Because of insufficiency of energy resources and pollution of environment, it is necessary to develop alternative energy sources. Nuclear fission energy is used widely for source of electric Power but being restricted due to radioactivity problem. Nuclear fission is highlighted as the new generation of nuclear energy and researched worldwide because of low risk of radiation effect. The representatives of fusion research is China's EAST, KSTAR of Korea and ITER of world. Korea Superconducting Tokamak Advanced Research(KSTAR) project is on progress for the completion in August, 2007. In this study, the research of utility system for KSTAR be carried out. The utility system of KSTAR is consist of water cooling & heating system, $N_2$ gas system, DI water system, service water system and instrument air & auto control system. The progress of KSTAR utility system is under commissioning state after construction completion. The optimal operation scenario will be verified during commissioning and adopted to the KSTAR operation.

• Proceedings of the Korean Nuclear Society Conference
• /
• 2005.05a
• /
• pp.1084-1085
• /
• 2005

• Nuclear Engineering and Technology
• /
• v.50 no.3
• /
• pp.411-415
• /
• 2018

Nuclear fusion may be among the strongest sustainable ways to replace fossil fuels because it does not contribute to acid rain or global warming. In this context, activated cobalt materials in corrosion products for fusion energy are significant in determination of dose levels during maintenance after a coolant leak in a nuclear fusion reactor. Therefore, cross-section studies on cobalt material are very important for fusion reactor design. In this article, the excitation functions of some nuclear reaction channels induced by proton particles on $^{59}Co$ structural material were predicted using different models. The nuclear level densities were calculated using different choices of available level density models in ALICE/ASH code. Finally, the newly calculated cross sections for the investigated nuclear reactions are compared with the experimental values and TENDL data based on TALYS nuclear code.

• Proceedings of the Korean Nuclear Society Conference
• /
• 2005.05a
• /
• pp.1092-1093
• /
• 2005

• Proceedings of the Korean Nuclear Society Conference
• /
• 2005.10a
• /
• pp.891-892
• /
• 2005

• Proceedings of the SAREK Conference
• /
• 2007.06a
• /
• pp.204-204
• /
• 2007

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2005.11a
• /
• pp.151-155
• /
• 2005

Though the nuclear fusion system has been fused into hydro-nuclear based on thermodynamics by tokamak system, there has been no success story. Because it's impossible to confine high temperatured plasma long Time actually. New nuclear-fusion-system using this nuclear-fusion-method will gather toroidal-magnetic-field by putting Core Block(C shaped torus iron) and toroidal-aluminium coil into toroidal magnetic-field-aluminium. That will arrange the nuclear-fusion-route on a gap fallen out by a part of cut torus-core and mkee the toroidal-an electric-current flow and electrolyze the fusioned-material (an electrolyte) into troidal-electrocity. That consists of troidal-magnetic-fild coil, toroidal-coial fusioned- material, series circuit. So toroidal-electocity will be changed into filament-electrocity and be introjected into fusioned-material. In a sapce on filament-electrocity, the magnetic inhaling-powr will enlarge to input-electrocity outside. This will exceed the Coulomb force and reache the nuclear-fusion. By this phenomenon there be quantity-loss. By this process I could confirmed that Einstein euation$(E=mC^2)$ releases into thermal energy.

• Proceedings of the Korean Nuclear Society Conference
• /
• 2004.10a
• /
• pp.719-720
• /
• 2004

A multi-megawatt long pulse ion source (LPIS) of neutral beam injector was developed for the KSTAR. Beam extraction experiments of the LPIS were carried out at the neutral beam test stand (NBTS). Design requirements for the ion source were 120 kV/65 A deuterium beam and a 300 s pulse length. A maximum ion density of $9.1310^{11}$ $cm^{-3}$ was measured by using electric probes, and an optimum arc efficiency of 0.46 A/kW was estimated with ion saturation current of the probes, arc power, and total beam area. An arcing problem, caused by the structural defect of decelerating grid supporter, in the third gap was solved by the blocking of backstream ion particles, originated from the plasma in the neutralizer duct, through the unnecessary spaces on the side of grid supporter. A maximum drain power of 1.5 MW (i.e. 70 kV/21 A) with hydrogen was measured for a pulse duration of 0.5 s. Optimum beam perveance was ranged from 0.75 to 0.85. An improved design of accelerator for the effective control of beam particle trajectory should provide higher beam perveance.

• Korean Journal of Animal Reproduction
• /
• v.21 no.3
• /
• pp.229-238
• /
• 1997

Chromosome condensation and swelling of the donor nucleus have been known as the early morphological indicators of chromatin remodelling after injection of a foreign nucleus into an enucleated recipient cytoplasm. The effects of non-preactivation and electrical preactivation of recipient cytoplasm, prior to fusing a donor nucleus, on the profile of nuclear remodelling in the nuclear transplant rabbit embryos were evaluated. The embryos of 16-cell stage were collected and synchronized to G1 phase of 32-cell stage. The recipient cytoplasms were obtained by removing the first polar body and chromosome mass by non-disruptive microsurgical procedure. The separated G1 phase blastomeres of 32-cell stage were injected into non-preactivated recipient cytoplasms. Otherwise, the enucleated recipient cytoplasms were preactivated by electrical stimulation and the separated G1 phase blastomeres of 32-cell stage were injected. After culture until 20h post-hCG injection, the nuclear transplant oocytes were electrofused by electrical stimulation. The nuclei of nuclear transplant embryos fused into non-preactivated and/or preactivated recipient cytoplasm were stained by Hoechst 33342 at 0, 1.5, 2, 4, 6, 8, 10 hrs post-fusion and were observed under an fluorescence microscopy. Accurate measurements of nuclear diameter were revealed with an ocular micrometer at 200$\times$. Upon blastomere fusion into non-preactivated recipient cytoplasm, a prematurely chromosome condensation at 1.5 hrs post-fusion and nuclear swelling at 8 hrs post-fusion were occurred as 91.6% and 86.1%, respectively. But the nuclei of nuclear transplant embryos fused into preactivated recipient cytoplasm, as o, pp.sed to non-preactivated recipient cytoplasm, were not occurred chromosome condensation and extensive nuclear swelling. Nuclear diameter fused into non-preactivated and preactivated recipient cytoplasm at hrs post-fusion was 30.2$\pm$0.74 and 15.2$\pm$1.32${\mu}{\textrm}{m}$, respectively. These results indicated that onset of unclear condensation and swelling which was associated with oocytes activation were critical steps in the process of chromatin swelling. Futhermore, complete reprogramming seemed only possible after remodelling of the donor nucleus by chromosome condensation and nuclear swelling.

• Nuclear Engineering and Technology
• /
• v.50 no.7
• /
• pp.1060-1067
• /
• 2018

A feasibility of reusing option of spent nuclear fuel in a fusion-fission hybrid system without partitioning was checked as an alternative option of pyro-processing with critical reactor system. Neutronic study was performed with MCNP 6.1 for this option, direct reuse of spent PWR fuel (DRUP). Various options with DRUP fuel were compared with the reference design concept; transmutation purpose blanket with (U-TRU)Zr fuel loading connected with pyro-processing. Performance parameters to be compared are transmutation performance of transuranic (TRU) nuclides, required fusion power and tritium breeding ratio (TBR). When blanket part is loaded only with DRUP, initial $k_{eff}$ level becomes too low to maintain a practical subcritical system, increasing the required fusion power. In this case, production rate of TRU nuclides exceeds the incineration rate. Design optimization is done for combining DRUP fuel with (U-TRU)Zr fuel. Reactivity swing is reduced to about 2447 pcm through fissile breeding compared to (U-TRU)Zr fuel option. Therefore, a required fusion power is reduced and tritium breeding performance is improved. However, transmutation performance with TRU nuclides especially $^{241}Am$ is degraded because of softening effect of spectrum. It is known that partitioning and transmutation should be accompanied with fusion-fission hybrid system for the effective transmutation of TRU.