• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.04a
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• pp.59-62
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• 2008

This paper presents the procedure and the results of modal identification testing of a seismic monitoring system central processing unit cabinet for a nuclear power plant. This paper also provides a model updating for making effective analytical modeling of cabinet-type electrical equipment by comparing the test results with the analysis results. From the test results and their interpretation, modal properties (modal frequency, mode shape, and modal damping) of the specimen were satisfactorily identified. However, the analysis results may need to study further to find the effective and presentative model for the cabinet-type electrical equipment. This paper just presents the first stage of the research project "Development of dynamic behavior analysis technique of dynamic structure system" which is trying to build the lumped mass beam stick model even their results do not agree well with the test results.

• Journal of the Korean Society of Industry Convergence
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• v.4 no.2
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• pp.119-125
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• 2001

This paper discuss the Qualification Test Procedure which is composed of main functional and environmental tests for the localizing avionics and subsystems, especially the detail test approaches of General Avionics Computed(GAC) through the analysis of related technical data packages for the purpose of performance proof of final products. Quality assurance procedures are properly established with the several kinds of inspections and functional test items. They are called as process inspections, functional test, acceptance test procedure and qualification test procedure. The Qualification test procedure are composed of the analysis of original engineering design concept and shall be performed for the acquisition of the certification of the GAC's quality as well as the aquisition of the related techniques and engineering know-how items.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.1
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• pp.23-29
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• 2017

In this study, a post-correlation analysis for shaking table test of square water storage tank is presented for the use of advances in earthquake-resistant design of liquid storage tank. For this purpose, the ANSYS CFX program is selected for the CFD analysis. Sensitivity analysis for resonant sloshing motion in terms of grid size and turbulence model suggested that (1) horizontal grid size as well as vertical grid size is a key variable in the sloshing analysis, and (2) the SST turbulence model is best for the sloshing analysis. Finally, correlation analyses for a non-resonant harmonic input and scaled earthquake excitation of the El Centro (1940) NS component are carried out using the grid and turbulence model established through the post-correlation analysis for the resonant motion. As a result, sloshing time histories by the CFD analysis agreed very well with the test results.

• Journal of the Korean Society for Railway
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• v.7 no.2
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• pp.149-154
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• 2004

Pile Bridge Abutments constructed on a soft base are affected by a lateral flow. Laterl flow pressure acting on Pile is very difficult to calculate because of, interation of ground and Pile. So, it is different to estimate displacement of Pile Bridge Abutments. This paper studied about possibility of the displacement estimation of Pile Bridge Abutments by using the equivalent sheet pile wall theory that was Randolph proposed in 1981. Analysis program through using the SAGE CRISP that is FEM program. Analysis data used Centrifuge test results of Springman(1991), Bransby(1997) and Ellis(1997)'s paper. In conclusion, maxium displacement that is carried out by centrifuge test and numerical analysis has occured at the head of pile, as well as Maximum displacement of pile is closely similar. But the moment acting on pile of numerical analysis is under estimated compare to the centrifuge test. Through the comparative study, it is found that displacement estimation by equivalent sheet pile wall is in relatively good agreement with the results of centrifuge test.

• Journal of the Korean Home Economics Association
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• v.49 no.6
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• pp.85-94
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• 2011

The purpose of this study was to validate the Korean Family Support & Challenge Questionnaire (K-SCQ), which is designed to assess family complexity in Children. There were 258 pre-test participants in this study and 498 senior students who were in elementary school. Results from the pre-test suggested us to use Likert scale over a dichotomous agree or disagree scale and positively items over negative ones. Results of the confirmatory factor analysis showed that the two factor structure (family support and challenge) of the SCQ fits well for Korean students. The K-SCQ has also good internal consistency. Further analysis was performed to explore the relationships between four family types based on K-SCQ and children's well-being and flow experience. It showed that the children in a high support/high challenge family had the highest emotional well-being, psychological well-being, and flow experience. These results suggest that the complex family characterized by high support and challenge has strong and positive impact on the children's quality of life.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.6 no.1
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• pp.54-57
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• 2005

A soft error rate neutrons is a growing problem fur terrestrial integrated circuits with technology scaling. In the acceleration test with high-density neutron beam, a latch-up prohibits accurate estimations of the soft error rate (SER). This paper presents results of analysis for the latch-up characteristics in the circumstance corresponding to the acceleration SER test for SRAM. Simulation results, using a two-dimensional device simulator, show that the deep p-well structure has better latch-up immunity compared to normal twin and triple well structures. In addition, it is more effective to minimize the distance to ground power compared with controlling a path to the $V_{DD}$ power.

• Culinary science and hospitality research
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• v.11 no.1
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• pp.87-104
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• 2005

A lifestyle changes according to environment. It appears more in the dietary life connected with the necessities in life. This study is executed empirically through the questionnaire that consists of selection attribute and variables connected with "well-being" that is examined in empirical analysis. It was carried out for 20 days from July 15 to August 5, 2003 with the customers who live in Seoul and the suburbs. With collected data, there were frequency analysis and factor analysis, reliability analysis using SPSS 10.0 packages, and T-test and ANOVA were enforced for the verification of differences between demographic elements with each factor. The result indicates that the inclinations of customers changed from the "well-being" trend have four factors: health consideration factor, food materials factor, cooking factor, and habit factor. And the housewife group shows the great changes in habit factor. In case of the changes according to incomes, the larger income earners tend to consider health more. In conclusion, people came to prefer the healthy Korean style food from the well-being trend.

• Proceedings of the Korea Water Resources Association Conference
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• 2004.05b
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• pp.298-302
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• 2004

In this study, the runoff reduction effect was analyzed quantitatively focusing on the infiltration collector well located in the test area. On the basis of the analysis of the data obtained by examining the real-time measurement field data, the runoff reduction was examined through the measured rainfall of the year 2003 by applying the analysis result, with the PCSWMM model to the Kiheung-Gugal residential area, which is selected as the test basin. According to the analysis, it is revealed that an infiltration collector well can reduce up to $65\~98\%$ of runoffs, compared to a conventional one. For measured rainfalls, an infiltration collector well was able to reduce up to $15\~23\%$ of runoffs and $3\~25\%$ of peak runoffs. These results show that the effects of infiltration collector wells might vary with rainfall intensity and its duration. However, the infiltration collector well was confirmed as the one of the alternatives of runoff reduction facilities in urbanized catchment.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1997.04a
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• pp.81-85
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• 1997

It is a well known fact that the exciter used in the vibration test interacts with the test structure and thus influences the test results. A two degree of freedom model of exciter is suggested and the vibration parameters of this model is experimentally extracted. According to this experimental results, the vibration parameters of the exciter can vary with respect to the test structure as well as the stinger used in the connecting mechanism. It is also found that the vibration parameters provided by the manufacturer can not be accurate and these parameter values should be revaluated based on the test environments.

• Nuclear Engineering and Technology
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• v.45 no.7
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• pp.895-910
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• 2013

The reflood test data from the rod bundle heat transfer (RBHT) test facility showed that the grids in the upper portion of the rod bundle could become wet well before the arrival of the quench front and that the sizes of liquid droplets downstream of a wet grid could not be predicted by the droplet breakup models for a dry grid. To investigate the water droplet generation from a wet grid spacer, a viscous linear temporal instability model of the water sheet issuing from the trailing edge of the grid with the surrounding steam up-flow is developed in this study. The Orr-Sommerfeld equations along with appropriate boundary conditions for the flow are solved using Chebyshev series expansions and the Tau-Galerkin projection method. The effects of several physical parameters on the water sheet oscillation are studied by determining the variation of the temporal growth rate with the wavenumber. It is found that a larger relative steam velocity to water velocity has a tendency to destabilize the water sheet with increased dynamic pressure. On the other hand, a larger ratio of steam boundary layer to the half water sheet thickness has a stabilizing effect on the water sheet oscillation. Droplet diameters downstream of the spacer grid predicted by the present model are found to compare reasonably well with the data obtained at the RBHT test facility as well as with other data recently reported in the literature.