• Nuclear Engineering and Technology
• /
• v.34 no.3
• /
• pp.232-241
• /
• 2002

A safety assessment is carried out for the near-surface radioactive waste disposal in the reference engineered vault facility. The analysis is mainly divided into two parts. One deals with the release and transport of radionuclide in the vault and unsaturated zone. The other deals with the transport of radionuclide in the saturated zone and radiological impacts to a human group under well drinking water scenario. The parameters for source-term, geosphere and biosphere models are mainly obtained from the site specific data. The results show that the annual effective doses are dominated by long lived, mobile radionuclides and their associated daughters. And it is found that the total effective dose for drinking water is far below the general criteria of regulatory limit for radioactive waste disposal facility.

• International Journal of Safety
• /
• v.8 no.2
• /
• pp.1-4
• /
• 2009

Various falling prevention systems with vertical guided rail have been supplied in order to prevent falling accidents and acquire the long life and cost down for the maintenance. Almost the imported system is composed of a guided rail and the comfort components. It has the mechanism that cannot be dismounted from the guided rail at the accident site. Thus, the aim of this study is to develop a falling prevent system that has a direct dismounting function, which can release easily from the falling accident point. This system has a high durability and robust. And the cost efficiency of the system and safety for workers also are improved remarkably. From the results, we showed the proposed new falling system is sufficiently safety and satisfies the KOSHA regulation through the numerical stress analysis. Also it is expected as the useful and effective safety device for workers.

• Archives of Plastic Surgery
• /
• v.49 no.6
• /
• pp.769-772
• /
• 2022

Femoral nerve injuries are devastating injuries that lead to paralysis of the quadriceps muscles, weakening knee extension to prohibit ambulation. We report a devastating case of electrical injury-induced femoral neuropathy, where no apparent site of nerve disruption can be identified, thus inhibiting the traditional choices of nerve reconstruction such as nerve repair, grafting, or transfer. Concomitant spinal cord injury resulted in spastic myopathy of the antagonist muscles that further restricted knee extension. Our strategy was to perform (1) supercharge end-to-side technique (SETS) to augment the function of target muscles and (2) fractional tendon lengthening to release the spastic muscles. Dramatic postoperative improvement in passive and active range of motion highlights the effectiveness of this strategy to manage partial femoral nerve injuries.

• Korean Journal of Remote Sensing
• /
• v.27 no.1
• /
• pp.43-49
• /
• 2011

In the face of growing concern about global warming, increasing attention has been focused on the reduction of carbon dioxide emissions. One method to mitigating the release of carbon dioxide is Carbon Capture and Storage (CCS). CCS includes separation of carbon dioxide from industrial emission in plants, transport to a storage site, and long-term isolation in underground. It is necessary to conduct analyses on optimal site selection, surface monitoring, and additional effects by the construction of CCS facility in Gyeongsang basin, Korea. For the optimal site selection, necessary data; geological map, landcover map, digital elevation model, and slope map, were prepared, and a weighted overlay analysis was performed. Then, surface monitoring was performed using high resolution satellite image. As a result, the candidate region was selected inside Gyeongnam for carbon storage. Finally, the related regulations about CCS facility were collected and analyzed for legal question of selected site.

• Journal of the Korean Society of Radiology
• /
• v.12 no.3
• /
• pp.297-304
• /
• 2018

U.S. nuclear power plant decommissioning guidelines(MARSSIM and MARLAP) are recommends to use DQOs when planning and conducting site surveys. The DQOs which is constructed in the site survey planning stage provide a way to make the best use of data. It helps we can get the important information and data to make decisions as well. From fifth to seventh steps of DQOs are the process of designing a site survey by using the collected data and information in the previous step to make reasonable and reliable decisions. The gray region that is set up during this process is defined as the range of concentrations where the consequences of type II decision errors are relatively small. The gray region can be set using DCGL and the average concentration of radionuclide in the sample collected at the survey unit. By setting up the gray region, site survey plan can be made most resource-efficient and the consequences on decision errors can be minimized. In this study, we set up the gray region by using the DCGL of Kori-1 which was derived from the previous research. In addition, we proposed a method to assess the concentration of radionuclide in samples for making decisions correctly.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
• /
• v.14 no.4
• /
• pp.423-434
• /
• 2016

The importance of severe nuclear accidents and probabilistic safety assessment (PSA) were brought to international attention with the occurrence of severe nuclear accidents caused by the extreme natural disaster at Fukushima Daiichi nuclear power plant in Japan. In Korea, studies on level 3 PSA had made little progress until recently. The code systems of level 3 PSA, MACCS2 (MELCORE Accident Consequence Code System 2, US), COSYMA (COde SYstem from MAria, EU) and OSCAAR (Off-Site Consequence Analysis code for Atmospheric Releases in reactor accidents, JAPAN), were reviewed in this study, and the disadvantages and limitations of MACCS2 were also analyzed. Experts from Korea and abroad pointed out that the limitations of MACCS2 include the following: MACCS2 cannot simulate multi-unit accidents/release from spent fuel pools, and its atmospheric dispersion is based on a simple Gaussian plume model. Some of these limitations have been improved in the updated versions of MACCS2. The absence of a marine and aquatic dispersion model and the limited simulating range of food-chain and economic models are also important aspects that need to be improved. This paper is expected to be utilized as basic research material for developing a Korean code system for assessing off-site consequences of severe nuclear accidents.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.5 no.2
• /
• pp.87-93
• /
• 2003

Litterfall and litter decomposition represent a major contribution to the carbon and nutrient inputs in a forest ecosystem. We measured litterfall quantity and nutrient dynamics in decomposing litter for two years at the Kwangneung broadleaf natural forest (DK site) in Korea. Litterfall was collected in circular littertraps (collecting area : 0.25 $m^2$) and mass loss rates and nutrient release patterns in decomposing litter were estimated using the litterbag technique employing 30 cm ${\times}$ 30 cm nylon bags with 1.5 mm mesh size. Total annual litterfall was 5,627 kg/ha/yr and leaf litter accounted for 61 % of the litterfall. The leaf litter quantity was highest in Quercus serrata, fallowed by Carpinus laxiflora and C. cordata, etc., which are dominant tree species in the site. Mass loss from decomposing leaf litter was more rapid in C. laxiflora and C. cordata than in Q. serrata litter. About 77% of C. laxiflora and 84% of C. cordata litter disappeared, while about 48% in Q. serrata litter lost over two years. Lower mass loss rates of Q. serrata litter may be attributed to the difference of substrate quality such as lower nutrient concentrations compared with the other litter types. Nutrient concentrations (N, P, Mg) of three litter types except for potassium (K) increased compared with initial nutrient concentrations of litter over the study period. Compared with Q. serrata litter, nutrients (N, P, K, Ca, Mg) in C. laxiflora and C. cordata litter were released rapidly. The results suggest that litter mass loss and nutrient dynamic processes among tree species vary considerably in the same site conditions.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.14 no.3
• /
• pp.209-221
• /
• 2002

In the present paper, a method which enhances the circulation of harbor waters by using wave energy was investigated. The overflow levee was selected as a coastal structure helping the harbor circulation, and was applied to Jeju-outer-port site so as to estimate its effectiveness quantitatively in probabilistic point of view. It was assumed that sea water influx rate through the overflow levee into the harbor depended upon wave height and tidal level and a functional relationship among them was calculated using the results of hydraulic experiment. The probability distribution of water influx could be obtained from hindcasted wave data and measured tidal elevations at Jeju harbor. The Gamma distribution was appeared to best fit the estimated influx distribution, and the optimal location of the levee was discussed. Finally, water quality purification effect was investigated by computing the contaminant material dispersion according to whether the levee was or not.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.12 no.3
• /
• pp.1111-1116
• /
• 2011

Heat exchangers have been used for the automotive, HVAC systems, and other various industrial facilities, so the market is very wide. In general, high-efficiency heat exchangers with louver fins are used in the dust-free environment while heat exchangers with wavy fins are used for dusty environment such as construction site, etc. In this study, numerical analysis has been performed for typical heat exchangers, used as oil coolers or fuel coolers, with dual cell model that can handle different grids for the air-side and oil-side of heat exchangers. First wind tunnel tests were conducted to obtain one-dimensional thermal performance data of heat exchangers. Then, heat release rates with varying air flows were numerically predicted using the three-dimensional dual-cell model. The model can greatly enhance the accuracy of thermal design since it includes the effects of nonuniformity of air flows across heat exchangers.

• BMB Reports
• /
• v.39 no.3
• /
• pp.270-277
• /
• 2006

Helices 4 and 5 of the Bacillus thuringiensis Cry4Ba $\delta$-endotoxin have been shown to be important determinants for mosquito-larvicidal activity, likely being involved in membrane-pore formation. In this study, the Cry4Ba mutant protein containing an additional engineered tryptic cleavage site was used to produce the $\alpha4$-$\alpha5$ hairpin peptide by an efficient alternative strategy. Upon solubilization of toxin inclusions expressed in Escherichia coli and subsequent digestion with trypsin, the 130-kDa mutant protoxin was processed to protease-resistant fragments of ca. 47, 10 and 7 kDa. The 7-kDa fragment was identified as the $\alpha4$-loop-$\alpha5$ hairpin via N-terminal sequencing and mass spectrometry, and was successfully purified by size-exclusion FPLC and reversed-phase HPLC. Using circular dichroism spectroscopy, the 7-kDa peptide was found to exist predominantly as an $\alpha$-helical structure. Membrane perturbation studies by using fluorimetric calcein-release assays revealed that the 7-kDa helical hairpin is highly active against unilamellar liposomes compared with the 65-kDa activated full-length toxin. These results directly support the role of the $\alpha4$-loop-$\alpha5$ hairpin in membrane perturbation and pore formation of the full-length Cry4Ba toxin.