• Nuclear Engineering and Technology
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• v.31 no.6
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• pp.8-22
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• 1999

This study was performed to comparatively evaluate selected Human Reliability Analysis (HRA) methods which mainly focus on cognitive error analysis, and to derive the requirement of a new human error analysis (HEA) framework for Accident Management (AM) in Nuclear Power Plants (NPPs). In order to achieve this goal, we carried out a case study of human error analysis on an AM task in NPPs. In the study we evaluated three cognitive HEA methods, HRMS, CREAM and PHECA, which were selected through the review of the currently available seven cognitive HEA methods. The task of reactor cavity flooding was chosen for the application study as one of typical tasks of AM in NPPs. From the study, we derived seven requirement items for a new HEA method of AM in NPPs. We could also evaluate the applicability of three cognitive HEA methods to AM tasks. CREAM is considered to be more appropriate than others for the analysis of AM tasks, HRMS is also applicable to the error analysis of AM tasks. But, PHECA is regarded less appropriate for the predictive HEA technique as well as for the analysis of AM tasks. In addition to these, the advantages and disadvantagesofeachmethodaredescribed.

• Ocean Systems Engineering
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• v.9 no.3
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• pp.261-285
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• 2019

Nowadays in offshore industry there are emerging hazards with vague property such as act of terrorism, act of war, unforeseen natural disasters such as tsunami, etc. Therefore industry professionals such as offshore energy insurers, safety engineers and risk managers in order to determine the failure rates and frequencies for the potential hazards where there is no data available, they need to use an appropriate method to overcome this difficulty. Furthermore in conventional risk based analysis models such as when using a fault tree analysis, hazards with vague properties are normally waived and ignored. In other word in previous situations only a traditional probability based fault tree analysis could be implemented. To overcome this shortcoming fuzzy set theory is applied to fault tree analysis to combine the known and unknown data in which the pre-combined result will be determined under a fuzzy environment. This has been fulfilled by integration of a generic bow-tie based risk analysis model into the risk assessment phase of the Risk Management (RM) cycles as a backbone of the phase. For this reason Fault Tree Analysis (FTA) and Event Tree Analysis (ETA) are used to analyse one of the significant risk factors associated in offshore terminals. This process will eventually help the insurers and risk managers in marine and offshore industries to investigate the potential hazards more in detail if there is vagueness. For this purpose a case study of offshore terminal while coinciding with the nature of the Caspian Sea was decided to be examined.

• Journal of Korean Tunnelling and Underground Space Association
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• v.3 no.4
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• pp.3-15
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• 2001

Generally, it has been noted that underground structures have a consistent record of suffering much less damage than surface facilities during earthquakes; but it is still necessary to illustrate the dynamic response of tunnel structures subject to earthquake loadings and to provide the appropriate method for the seismic analysis of underground tunnel structures since many types of underground structures have been and will be constructed in countries situated within seismic zones. In this study, first, seismic analyses for underground tunnel structures are performed by using quasistatic analysis method and dynamic analysis method. Second, seismic analyses in tunnel portals are performed by using above methods. The results of seismic analyses for the tunnel structure show that the tunnel structure conforms to ground deformation and that seismic design by using the quasi-static analysis method is more conservative than that by using the dynamic analysis. The results of the dynamic FEM analysis for the tunnel structure show that the simplified 2-D FEM analysis using a sine wave rather than the 3-D FEM analysis can be adopted for seismic analysis. Finally, the results of the dynamic FEM analysis in tunnel portals show that the force acting on the lining is largest near to the tunnel portal when an earthquake wave propagates parallel to tunnel axis.

• Journal of Ocean Engineering and Technology
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• v.15 no.2
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• pp.120-123
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• 2001

Despite the increasing necessity of accurate estimation of ring-stiffened cylinders'ultimate strength, the complex structural behavior of cylinders has made their design mainly depend on empirical formulas mostly based on limited test data rather than theoretical background. This paper has developed the imperfection method which enables the ultimate strength analysis of buckling-sensitive structures by combining two separate functions covered by common commercial finite element softwares, which are linear elastic buckling analysis and nonlinear stress analysis. Developed method was applied to two of the world most renowned softwares, MSC/NASTRAN and ABAQUS, for the analysis of ring-stiffened cylinders and unexpectedly big difference in their analysis results was found. This tells that many widely used commercial softwares have their different strong points and weak points and the choice of commercial software should be cautiously made after thorough inspection. This paper ends with some useful information about which of the two aforementioned softwares is more respectively for the linear elastic buckling analysis and the ultimate strength analysis of ring-stiffened cylinders.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.957-965
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• 2008

Recently, slope stability analysis in current design criteria is criticized for its unrealistic assumption of groundwater table and slope stability analysis incorporating seepage analysis considering rainfall is gaining a recognition as an alternative. However, a reasonable method for determining the rainfall used in the seepage analysis has not yet been established. Rainfall input for seepage analysis is a time series of rainfall and is similar to the hyetograph which is usually obtained from hydrology. In this paper a method to obtain the hyetograph from the intensity-duration-frequency is proposed. The resulting hyetograph can be used in the in the slope design stage. Also some considerations for practical application of slope stability analysis considering the rainfall is included.

• The Transactions of the Korea Information Processing Society
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• v.6 no.3
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• pp.710-721
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• 1999

In this paper, we have designed and implemented a parameter extraction system for analyzing Internet using SNMP. The extraction system has two modules; one is collection request module, and the other is analysis request module. The collection request module generates a polling script, which is used to collect management information from the managed system periodically. With this collected data, analysis request module extracts analysis parameters. These parameters are traffic flow analysis, interface traffic analysis, packet traffic analysis, and management traffic analysis parameter. For management activity, we have introduced two-step-analysis-view. One is Summary-View, which is used find out malfunction of a system among the entire managed systems. The Other is Specific-View. With this view we can analyze the specific system with all our analysis parameters. To show available data as indicators for line capacity planning, network redesigning decision making of performance upgrade for a network device and things like that.

• Journal of Information Technology Applications and Management
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• v.29 no.3
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• pp.75-93
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• 2022

The purpose of this study is to compare and analyze each government's ICT SME support policies to cope with changes in the ICT ecosystem paradigm. In particular, the core policies and policy trends of the Moon's government are presented through keyword network analysis and cognitive map analysis. As a result, core technologies such as ICT(Information Communication Technology), AI(Artificial Intelligence), Big Data, and 5G, which have high values of betweenness centrality and closeness centrality, are major keywords with high propagation power. The cognitive map analysis shows that the opportunity factors for the 4th industrial revolution are being activated through the ICT infrastructure circulation process, the domestic market circulation process, and the global market circulation process. This study is meaningful in terms of cognitive map analysis and utilization based on scientific analysis.

• The Journal of the Korea Contents Association
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• v.21 no.2
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• pp.271-279
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• 2021

This study wanted to see if there was a difference in the development of counselors before and after sandplay education analysis and verbal education analysis. Ten people were selected for the sandplay education analysis and the level of counselor development before and after receiving the verbal education analysis, divided into three groups that received the verbal education analysis, and the three groups that received the language education analysis. A nonparametric test, Kruskal-Wallis test, was conducted to identify differences in the results of the pre-parametric test, and a nonparametric test, Wilcoxon signed tank test was conducted to identify differences in the pre-post test results. Studies have shown that there is a statistically significant difference in the overall development of counselors and in case of case, in the whole of sandplay education analysis groups, while those that received verbal education analysis and those that did not receive education analysis do not have a statistically significant difference in the level of counselors development. This study is meaningful as it proves that sand play education analysis is effective in the development of counselors.

• International Journal of Naval Architecture and Ocean Engineering
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• v.5 no.4
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• pp.598-613
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• 2013

This paper deals with the dynamic effect of pipeline installation and embedment for the on-bottom stability design of offshore pipelines on soft clay. On-bottom stability analysis of offshore pipelines on soft clay by DNV-RP-F109 (DNV, 2010) results in very unreasonable pipe embedment and concrete coating thickness. Thus, a new procedure of the on-bottom stability analysis was established considering dynamic effects of pipeline installation and pipe-soil interaction at touchdown point (TDP). This analysis procedure is composed of three steps: global pipeline installation analysis, local analysis at TDP, modified on-bottom stability analysis using DNV-RP-F109. Data obtained from the dynamic pipeline installation analysis were utilized for the finite element analysis (FEA) of the pipeline embedment using the non-linear soil property. From the analysis results of the proposed procedure, an optimum design of on-bottom stability of offshore pipeline on soft clay can be achieved. This procedure and result will be useful to assess the on-bottom stability analysis of offshore pipelines on soft clay. The analysis results were justified by an offshore field inspection.

• Journal of Engineering Education Research
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• v.18 no.6
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• pp.64-69
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• 2015

A video-work story analysis system based on emotional state measurement includes a content provision unit which provides story content of a video-work, a display unit which displays content provided by the content provision unit, an emotional state measurement unit which measures a tense-relaxed emotional state of a viewer viewing the displayed story content, a story pattern analysis unit which analyzes the tense-relaxed emotional state measured from the emotional state measurement unit according to a scene in the story content provided by the content provision unit, and a story pattern display unit which prints out an analysis result or displays the analysis result as an image. The emotional state measurement unit measures a tense or relaxed emotional state through one or more analyses among a brainwave analysis, a vital sign analysis, or an ocular state analysis. A writer may obtain support in an additional scenario modification work, and an investor may obtain support in making a decision through the above description. Furthermore, the video-work story analysis system and analysis method based on emotional state measurement may extract a particular pattern with respect to a change in an emotional state of a viewer, compile statistics, and analyze a correlation between a story and an emotional state.