• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2003.11a
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• pp.369-372
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• 2003

To obtain a low ground resistance in high resistivity soil or in insufficient place such as downtown, long vertical ground rods are often used. However, if the lightning current or fault current with high frequency flows into the grounding system, the ground impedance is remarkedly increased. This paper presents how the impulse and fault current works on the long. vertical ground rods associated with incoming points. When the test current was injected at the bottom of ground rod, the potential waveform of ground rod includes the oscillation with high frequency.

• Nuclear Engineering and Technology
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• v.52 no.1
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• pp.135-147
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• 2020

A methodology for evaluation of mechanical and thermal effects of localized non-axisymmetric oxidation in zircaloy claddings on LWR fuel reliability is proposed. To this end, the basic capabilities of the FALCON fuel behaviour code are used. Examples of methodology application to adjustment of selected operational limits for modern BWR fuel rods, to capture effects of the excess local oxidation, are presented. Specifically, the limiting rod internal pressure for the onset of cladding lift-off is reduced, depending on initial excess oxidation spot sizes. Also, the power limits for Anticipated Operational Occurrences are adjusted, to preclude fuel melting and cladding failure due to PCMI and PCI-SCC in the affected fuel rods.

• Journal of Chest Surgery
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• v.32 no.9
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• pp.844-846
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• 1999

Chronic irritation to arterial wall by foreign material may give rise to delayed vascular injury. A 50 years old male patient with kyphoscoliosis had undergone fixation of orthopedic Cotrel-Dubousset(CD) rods and screws. Fourteen months after that surgery, a false aneurysm of the descending thoracic aorta associated with pulsating hematoma in the muscular chest wall developed. The false aneurysm was managed by resecting the diseased aortic segment and replacing the vascular graft.

• Korean Journal of Veterinary Research
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• v.25 no.1
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• pp.61-67
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• 1985

One hundred and twenty seven strains of Gram-negative rods (72 E. coli, 45 Klebsieila pneumoniae, 8 Enterobacter spp. and 2 Pseudomonas aeruginosa) isolated from bovine mastitis were examined for resistance to ampicilin, carbenicillin and cefazolin, ${\beta}$-lactamase activity and transferable ${\beta}$-lactamase plasmids. Stains resistant to ampicillin were 13.9% in E. coli, 93.3% in Klebsiella pneumoniae, 87.5% in Enterobacter. spp. and all in Pseudomonas aeruginosa, Resistance of E. coli, Klebsiella pneumoniae and Enterobacter spp. to ampicillin was due to the ${\beta}$-lactamases, but all Pseudomonas aeruginosa exhibited a high level of the non-enzymic resistance. Transferable plasmid-mediated ${\beta}$-lactamase synthesis was demonstrated in 61.9% of Klebsiella pneumoniae, 50% of E. coli and 42.9% of Enterobacter spp. The same ${\beta}$-lactamase plasmids specified different resistance levels to various ${\beta}$-lactam antibiotics in different recipients.

• Nuclear Engineering and Technology
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• v.50 no.7
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• pp.1148-1153
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• 2018

The Leaking Fuel Experiment test facility was designed to simulate the activity release from spent leaking fuel rods under steady state and transient conditions in the spent fuel pool. The experimental rig included an electrically heated fuel rod with different defects and a cooling system. The fission product transport was simulated by potassium-chloride. The conductivity changes of the water in the cooling system were measured to provide information about the amount of released solution. Defects of different sizes and positions were applied, together with a wide range of rod powers to simulate decay heat. The produced data can be used for predicting the activity release from leaking fuel under storage conditions and for the interpretation of fuel examination procedures.

• Nuclear Engineering and Technology
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• v.50 no.7
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• pp.1024-1036
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• 2018

In this paper, McCARD code was verified using various models listed in the NUREG/CR-6361 benchmark guide, which provides specifications for single pin-cells, single assemblies, and the whole core classified depending on the nuclear properties and structural characteristics. McCARD code was verified by comparing its results with those of SCALE code for single pin-cell and single assembly benchmark problems. The difference in the multiplication factor obtained through the two codes did not exceed 90 pcm. The benchmark guide treats a total of 173 whole core experiments. The experiments are categorized as simple lattices, separator plates, reflecting walls, reflecting walls and separator plates, burnable absorber fuel rods, water holes, poison rods, and borated moderator. As a result of numerical simulation using McCARD, the mean value of the multiplication factors is 1.00223 and the standard deviation of the multiplication factors is 285 pcm. The difference between the multiplication factors and the experimental value is in the range of -665 pcm to + 1609 pcm. In addition, statistics of results for experiments categorized by reactor shape, additional structure, burnable poison, etc., are detailed in the main text.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.19 no.2
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• pp.215-223
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• 2021

The domestic CANDU nuclear power plants have been operated for a long time and various unforeseen spent fuel defects have been discovered. As the spent fuel defects are important factors in the safety of the nuclear power plant, a study on the analysis of the spent fuel defects to prevent their recurrence is necessary. However, in cases where the fuel rods inside the fuel assembly are defected, it is difficult to dismantle the fuel assembly owing to their welded structure and the facility conditions of the plant. Therefore, it is impossible to analyze the spent fuel defect because it is difficult to visually check the shape of the fuel defect. To resolve these problems, an analysis technology that can predict the number of defected fuel rods and defect size was developed. In this study, we developed a methodology for investigating the root cause of spent fuel defects using a database of the earlier fuel defects in the plants. It is anticipated that in the future this analysis technology will be applied when spent fuel defects occur.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.235.1-235.1
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• 2003

With an aim of obtaining high efficacy in cartilage regeneration, implantable polymeric rods were fabricated. These rod-type matrices were anticipated to perform structural tissue supporting activity and enhance extracellular matrix (ECM) formation by releasing specific agent, DHEA-S, in controlled manner. It is expected that application for the drilling operation on the articular cartilage of OA patients as the implants may promote regeneration of their cartilage. Osteoarthritis (OA) is a degenerative joint disease characterized by progressive loss of articular cartilage, subchondral bone remodeling, spur formation, and synovial inflammation. (omitted)

• Nuclear Engineering and Technology
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• v.55 no.9
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• pp.3241-3251
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• 2023

The potential for recriticality and sub-critical boron concentrations is analyzed during the relocation of the fuel rods in the assembly, which we call late phase of a severe accident, via coupling between MELCOR and whole-core Monte Carlo analyses by Serpent 2. The recriticality, initiated during the early phase, is found to maintain when the fuel assemblies containing intact fuel rods are submerged by the cooling water. It is also found that the effect of the negative reactivity insertion via remaining fission products in the fuel debris increases as the burnup increases. The sub-critical boron concentrations during the late phase are found to be 76~544 ppm lower than those during the early phase. Therefore, it can be concluded that the boron concentration that prevents recriticality not only during the early phase but also during the late phase is the sub-critical boron concentration during the early phase.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.06a
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• pp.142-143
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• 2020

A study was conducted on the production of LEFC using the Precast method, not the on-site construction. LEFC, Light Emotion Friendly Concrete, has the advantage of plastic rods being inserted to allow light to transmit, but because of the lack of adhesion to concrete, it leads to a decline in mechanical performance and durability. Therefore, it is necessary to apply precasting techniques to ensure homogeneous and superior quality of LEFC. In this study, wooden molds were used and plastic rods were arranged on porous acrylic plates. Prototyping was carried out with a UHPC mix proportioning to ensure flowability, self-consolidating performance and mechanical performance.