• Nuclear Engineering and Technology
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• v.54 no.10
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• pp.3909-3918
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• 2022

In the event of a severe accident, the reactor core may melt due to insufficient cooling. the high-temperature core melt will have a strong interaction (FCI) with the coolant, which may lead to steam explosion. Steam explosion would pose a serious threat to the safety of the reactors. Therefore, the study of steam explosion is of great significance to the assessment of severe accidents in nuclear reactors. This research focuses on the development of a two-dimensional steam explosion integrated analysis code called SEINA. Based on the semi-implicit Euler scheme, the three-phase field was considered in this code. Besides, the influence of evaporation drag of melt and the influence of solidified shell during the process of melt droplet fragmentation were also considered. The code was simulated and validated by FARO L-14 and KROTOS KS-2 experiments. The calculation results of SEINA code are in good agreement with the experimental results, and the results show that if the effects of evaporation drag and melt solidification shell are considered, the FCI process can be described more accurately. Therefore, it is proved that SEINA has the potential to be a powerful and effective tool for the analysis of steam explosions in nuclear reactors.

• Structural Engineering and Mechanics
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• v.56 no.4
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• pp.549-567
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• 2015

A first-order moment method (FORM) reliability analysis is commonly used for structural stability analysis. It requires the values and partial derivatives of the performance to function with respect to the random variables for the design. These calculations can be cumbersome when the performance functions are implicit. A Gaussian process (GP)-based response surface is adopted in this study to approximate the limit state function. By using a trained GP model, a large number of values and partial derivatives of the performance functions can be obtained for conventional reliability analysis with a FORM, thereby reducing the number of stability analysis calculations. This dynamic renewed knowledge source can provide great assistance in improving the predictive capacity of GP during the iterative process, particularly from the view of machine learning. An iterative algorithm is therefore proposed to improve the precision of GP approximation around the design point by constantly adding new design points to the initial training set. Examples are provided to illustrate the GP-based response surface for both structural and non-structural reliability analyses. The results show that the proposed approach is applicable to structural reliability analyses that involve implicit performance functions and structural response evaluations that entail time-consuming finite element analyses.

• Korean Journal of Veterinary Research
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• v.39 no.5
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• pp.896-907
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• 1999

The morphometrical characteristics such as external measurements and mandible size assessment in mice and rats have to be highly heritable and sufficiently variable between strains in order to calculate a strain specific profiles. The coat color of Korean wild rats were observed and morphometric analysis of external measurements were carried out on Korean wild rats compared to laboratory strains in order to clarify the genetic characteristics of Korean wild rats and to establish background data as a domestication of Korean wild rats for new laboratory strain. Korean wild rats were captured from Chunchon and Hoengsong. 4 inbred and 1 outbred strains of rats were used in this study for the comparison of genetic characteristic of Korean wild rats. Total body length, head length, tail length, hind foot length and ear length were measured and then statistical analysis were carried out by discrimiant analysis. The coat color of Korean wild rat showed golden white in ventral portion and dark agouti in dorsal portion. Korean wild rats could be distinguished from the other laboratory strains distinctly by morphogenetical analysis. There was significant variations among Korean wild rat compared to those of the other laboratory strains of rat. This study may provide that Korean wild rats have a unique genetic characterization compared to those of other inbred strains of rats based on morphogenetical characteristics by external measurements.

• Proceedings of the Korean Vacuum Society Conference
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• 1996.02a
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• pp.162-162
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• 1996

• Journal of the Korean Society of Safety
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• v.39 no.1
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• pp.104-113
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• 2024

Unlike in general manufacturing process, safety management in laboratory-based research area is complicated because the latter generally involves trying untested methods or handling unusual substances in small amounts. Laboratory accidents in South Korea have recently shown an increasing trend. Unfortunately, statistics on such accidents are not officially published by any domestic public agencies. In this study, multivariate analysis was performed on the relationships between variables to develop effective strategies for preventing laboratory accidents. A Cross-Tabulation Analysis of accident-related factors in 179 accident cases revealed that the laboratory type, accident type, and unsafe-act type are all statistically significant, whereas the unsafe condition and management factors differ with the statistical criteria. Furthermore, the results of a Multiple-Correspondence Analysis showed that accidents can be divided largely into three groups having different accident causes and injury types; this confirms the necessity of different strategies to prevent accidents of each type. The findings also reveal differences between the distribution of accident types mentioned in the accident case collection books and actual reported cases. This suggests that an official statistical system administered by a public institution would be necessary for effective prevention of laboratory accidents.

• Structural Engineering and Mechanics
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• v.7 no.6
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• pp.589-599
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• 1999

This paper presents the development and applications of the software package JIFEX, a new finite element system which can be used for structural analysis and optimum design by the modern computer hardware and software technologies such as MS Windows95/NT and Pentium PC platforms. The complete system of JIFEX is programmed with $C/C^{++}$ language to make full use of advanced facilities of MS Windows95/NT. In the system, the finite element data pre-processing, based on the most popular CAD package AutoCAD (R13, R14), has been implemented, so that the finite element modeling could be integrated with geometric modeling of CAD. The system not only has interactive graphics facility for data post-processing, but also realizes the real-time computing visualization by means of the Dynamic Data Exchange (DDE) technique. Running on the Pentium computers, JIFEX can solve large-scale finite element analysis problems such as the ones with more than 60000 nodes in the finite element model.

• Proceedings of the Korean Nuclear Society Conference
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• 2005.10a
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• pp.761-762
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• 2005

• BMB Reports
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• v.37 no.1
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• pp.45-52
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• 2004

The goal of interaction proteomics that studies the protein-protein interactions of all expressed proteins is to understand biological processes that are strictly regulated by these interactions. The availability of entire genome sequences of many organisms and high-throughput analysis tools has led scientists to study the entire proteome (Pandey and Mann, 2000). There are various high-throughput methods for detecting protein interactions such as yeast two-hybrid approach and mass spectrometry to produce vast amounts of data that can be utilized to decipher protein functions in complicated biological networks. In this review, we discuss recent developments in analytical methods for large-scale protein interactions and the future direction of interaction proteomics.

• Journal of Applied Reliability
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• v.14 no.2
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• pp.93-96
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• 2014

RFID (Radio Frequency IDentification) system is recognition technology which can maintain various object's information. Reliability of RFID tags is the most important factor in RFID system. In this paper, we proposed ALT (Accelerated Life Test) method for UHF RFID tags. Temperature and humidity were adopted as stress factors and the accelerated life tests were conducted in three different conditions. We performed failure analysis for identifying failure mechanism and statistical analysis of test data. In the statistical analysis, we employed Inverse Power law for relationship between tag's life and stress. Through the statistical analysis, we proposed acceleration factor for several levels of temperature-humidity. The reliability qualification test plans were also designed for the tag's target reliability.

• Journal of The Korean Association For Science Education
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• v.12 no.1
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• pp.93-101
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• 1992

The purposes of this study were; 1) to apply the network analysis to evaluation of students' laboratory reports, 2) to test the applicability of the systematic network analysis. For this purposes, 7th grade 88 students from 22 middle schools in Inchon city of Korea were selected and their laboratory reports were evaluated by a evaluation criterion network developed in this study. The evaluation criterion consisted of 4 categories and 10 subcategories. The results of this study suggested that the network analysis approach was suitable one for the evaluation of students' laboratory reports. This was supported by total score distribution, means/weight, Cronbach's ${\alpha}$ coefficient(0.70), and the subcategories' reliabilities. The resluts of the factor analysis indicated that the evaluation criterion network of this study had two factors.