• Journal of Radiation Protection and Research
• /
• v.21 no.4
• /
• pp.313-327
• /
• 1996

As an at-reactor(AR) storage method o( spent fuel, there are horizontal concrete module type, metal storage cask type, concrete storage cask type, dual purpose (transportation and storage) cask type and multi-purpose (transportation, storage and disposal) cask type. All other types except multi-purpose one have been already used for AR dry storage of spent fuels after obtaining operation license in various foreign countries. Also the development of multi-purpose type has been continued for operation license. In America, Japan, Germany, Canada, Spain, Switzerland, and Czech Republic, etc., AR dry storage facilities are under operation or on propulsion, and spent fuels are transported to interim storage facility or reprocessing plant after dry storage at reactor temporarily. At Wolsung site, in case of Korea, concrete silo type has already been introduced, and it is believed to be inevitable to store spent fuels at reactor temporarily, considering the reality that storage capacity of spent fuel is approaching to the limit in some nuclear power plants. In this report, the system characteristics, design requirements, technical standards and status of AR storage system, which is suitable for domestic site such as Kori, have been studied. In most cases, the licensed period of storage cask is limited up to 20 years and the integrity of material and maintenance of leaktightness are required during the whole service life.

• Nuclear Engineering and Technology
• /
• v.48 no.3
• /
• pp.624-634
• /
• 2016

Nuclear criticality safety analyses (NCSAs) considering burnup credit were performed for the GBC-32 cask. The used nuclear fuel assemblies (UNFAs) discharged from Hanbit Nuclear Power Plant Unit 3 Cycle 6 were loaded into the cask. Their axial burnup distributions and average discharge burnups were evaluated using the DeCART and Multi-purpose Analyzer for Static and Transient Effects of Reactors (MASTER) codes, and NCSAs were performed using SCALE 6.1/STandardized Analysis of Reactivity for Burnup Credit using SCALE (STARBUCS) and Monte Carlo N-Particle transport code, version 6 (MCNP 6). The axial burnup distributions were determined for 20 UNFAs with various initial enrichments and burnups, which were applied to the criticality analysis for the cask system. The UNFAs for 20- and 30-year cooling times were assumed to be stored in the cask. The criticality analyses indicated that $k_{eff}$ values for UNFAs with nonuniform axial burnup distributions were larger than those with a uniform distribution, that is, the end effects were positive but much smaller than those with the reference distribution. The axial burnup distributions for 20 UNFAs had shapes that were more symmetrical with a less steep gradient in the upper region than the reference ones of the United States Department of Energy. These differences in the axial burnup distributions resulted in a significant reduction in end effects compared with the reference.

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 1996.10a
• /
• pp.70-77
• /
• 1996

In this study, sliding response analysis of free standing structure such as multi-purpose nuclear spent fuel storage cask is peformed. The governing factors of sliding response are aspect ratio of structure and ground acceleration. The vertical acceleration component is very important factor in the sliding response of the structure. Based on the mathematical model, computer program is developed using direct forward integration method to predict the sliding response. Using the program, several parametric studies were made for sinusodial ground motion and for El Centre 1940 earthquake and Mexico 1973 earthquake. From the results, it is known that the frequency content and duration of strong motion affect the sliding of the structure.

• Korean Journal of Child Studies
• /
• v.18 no.2
• /
• pp.311-331
• /
• 1997

This study investigated the relationship between preschool children's social competence and perceived social support. The subjects were 85 children enrolled in 10 kindergartens and nurseries located in Seoul. Social support was assessed by children themselves with a social support dialogue Cask, "My Family and Friends," developed by Reid, Lamdegman, and Jaccard (1989). This task consists of 12 dialogues based on Vygotskian principles. Social competency was assessed by teachers with a slightly modified version of Song's Iowa Social Competency Scale (ISCS). The data were analyzed by frequencies percentiles, mean, one-way ANOVAs, and Pearson's correlations. Results showed that (1) Children perceived parents to be the best multi-purpose social providers: mothers for emotional support and fathers for instrumental support. (2) Children with unemployed mothers perceived higher maternal emotional, informational, and instrumental support than children with employed mothers. (3) Middle-class children perceived higher friendship support than upper-or lower-class children. (4) Friendship support was the one variable most significantly related to children's social competence.