• Proceedings of the KSR Conference
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• 2002.10a
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• pp.608-613
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• 2002

This study was under taken as an analysis of failure mode in a railroad bed reconstructed with miniaturized Geotextile Container after being destroyed by heavy rain. It assesses the practical use of the bag shaped Geotextile Container method in the rehabilitation of destroyed roadbeds. The failure mode was assessed using the laboratory model tests to determine the following criteria: Strain of Geotextile Container, Vertical ＆ Horizontal displacements of Geotextile Container layer, and the transmitting load effects due to the applied load. The Geotextile Container layer was failed as a Block Failure type, although there was some variation in the results between the saturated and unsaturated conditions. The main failure was caused by the reduction of the interface friction between Geotextile Containers. The result of this mobilizes the significant horizontal displacement and the ultimate failure of the Geotextile Container layer. The strain on the wet Geotextile Container was occurred about two times greater than that of dry condition.

• IE interfaces
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• v.16 no.1
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• pp.27-33
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• 2003

The maintenance cost in K Steelworks has been continuously increased in proportion to the production cost. However, there seems to be a possibility of reducing cost through the optimization of maintenance actions. The failure types of the equipment in steelworks ate various with different failure cost. Thus the failure rate and cost of each type of failures should be considered simultaneously when the optimum maintenance period is to be determined. It is considered that the equipment undergoes periodic replacement and a specified number of incomplete preventive maintenance actions are performed during a replacement period. Assuming that the time to failure follows a Weibull distribution, the parameters of the failure rate are estimated using the maximum likelihood estimation. The optimal replacement period is determined to minimize the average cost per unit time. As the result of analysis it is suggested that the existing maintenance period for a hot-rolling equipment can be extended significantly.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.5 no.5
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• pp.11-21
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• 2002

A series of model tests is performed to evaluate the relationship between soil and a buried pipe in soil undergoing lateral movement. As the result of the model tests, a wedge zone and plastic flow zones could be observed in front of the pipe. And also an arc failure of cylindrical cavity could be observed at both upper and lower zones. Failure shapes in both cohesionless and cohesive soils are nearly same, which was investigated failure angle of $45^{\circ}+{\phi}/2$. In the cohesionless soil, the higher relative density produces the larger arc of cylindrical cavity. On the basis of failure mode observed from model tests, the lateral earth pressure acting on a buried pipe in soil undergoing lateral movement could be applying the cylindrical cavity extension mode. The deformation behavior of soils was typically appeared in three divisions, which are elastic zones, plastic zones and pressure behavior zones.

• Journal of Chest Surgery
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• v.25 no.4
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• pp.424-428
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• 1992

Post-AMI VSD is an infrequent but often catastrophic complication of acute myocardial infarction In general, the mortality is associated with end organ failure due to low output syndrome. Therefore, a stable hemodynamic is necessary to prevent the end organ failure. If a supportive therapy does not accomplish it, surgical intervention should be considered. Recently, we have experinced a case of post-AMI VSD with cardiogenic shock. Early recognition and surgical repair of post-AMI VSD gave us a good result. Postoperative result was satisfactory and recovery was uneventful. We believe that early surgical repair can be lifesaving in the case of post-AMI VSD with cardiogenic shock.

• Journal of Korean Elementary Science Education
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• v.36 no.4
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• pp.439-446
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• 2017

The purpose of this study was to compare Grit, failure tolerance and psychological well-being between elementary science gifted and general students. The subjects of this study were 48 science gifted students and 70 general students in the 5th and 6th grade of elementary school in Gyeonggi province. The results of this study were as follows: First, Grit, failure tolerance and psychological well-being of science gifted students were higher than those of the general students, there was a statistically significant difference. Second, science gifted students showed higher correlation between grit and failure tolerance, grit and psychological well-being than general students. Grit of science gifted students had a positive correlation with all sub-factors of academic failure tolerance and psychological well-being. In general students, there was a positive correlation with all sub-factors of Grit, academic failure tolerance, and psychological well-being except for the emotion sub-factor of academic failure tolerance. Thirdly, as a result of the regression analysis on the elements of failure tolerance affecting the Grit, science gifted students showed emotional factor but general students had behavioral factors. Also, as a sub-factor of psychological well-being on Grit, both science gifted and general students showed autonomy.

• Journal of the Korean Society of Safety
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• v.31 no.6
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• pp.58-66
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• 2016

This study aims to estimate the failure probability of concrete gravity dams for their risk analysis under flood situation. To the end, failure modes of concrete gravity dams and their limit state functions are proposed based on numerous review of domestic and international literatures on the dam failure cases and design standards. Three failure modes are proposed: overturning, sliding, and overstress. Based on the failure modes the limit state functions, the failure probability is assessed for a weir section and a non-weir section of a dam in Korea. As water level is rising from operational condition to extreme flood condition, the failure probability is found to be raised up to the warning condition, especially for overturning mode at the non-weir section. The result can be used to reduce the risk of the dam by random environmental variables under possible flood situation.

• Steel and Composite Structures
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• v.39 no.2
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• pp.201-213
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• 2021

Currently, there is a lack of research in the design approach to avoid column wall failure in the concrete filled double skin steel tubular (CFDST) column-beam connections. In this paper, a finite element model has been developed and verified by available experimental data to analyze the failure mechanism of CFDST column-beam connections. Various finite element models with different column hollow ratios (χ) were established. The simulation result revealed that with increasing χ the failure mode gradually changed from yielding of end plate, to local failure of the column wall. Detailed parametric analyses were performed to study the failure mechanism of column wall for the CFDST column-beam connection, in which the strength of sandwiched concrete and steel tube and thickness of steel tube were incorporated. An analytical model was proposed to predict the moment resistance of the assembled connection considering the failure of column wall. The simulation results indicate that the proposed analytical model can provided a conservative prediction of the moment resistance. Finally, an upper bound value of χ was recommend to avoid column wall failure for CFDST column-beam connections.

• Asia Marketing Journal
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• v.9 no.3
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• pp.75-115
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• 2007

This study investigated the effect of service provider's recovery effort and pre-failure customer-employee rapport on post-recovery consumer response such as satisfaction, purchase intention, and positive Word-of-Mouth communication. First, this study explored the interaction effect of recovery effort and customer-employee rapport on post-recovery consumer response. The result shows when the level of pre-failure customer-employee rapport is high, customer's positive responses decreased slightly even though they perceived low recovery effort. However, when the level of pre-failure customer-employee rapport is low, customer's responses were decreased considerably in case of low recovery effort. Second, this study examined 'service recovery paradox' which is post-recovery consumer's satisfaction is greater than the case of no service failure. The result shows recovery paradox was not supported in all samples regardless of the level of recovery effort and customer-employee rapport. Synthetically, customer-employee rapport took a buffering role in customer response after service failure although it's not the same as error-free state.

• Journal of the Korean GEO-environmental Society
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• v.5 no.1
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• pp.55-64
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• 2004

Stone column is a soil improvement method and can be applicable for loose sand or weak cohesive soil. Since the lack of sand in korea, stone column seems one of the most adaptable approach for poor ground as a soil improvement technique. However, this method was not studied for practical application. In this paper, the most affective design parameters for the bearing capacity of stone column were studied. The parametric study of major design factors for single stone column was carried out under the bulging and general shear failure condition, respectively. Especially, a test result of single stone column by static load was compared with the bearing capacity values of suggested formulas. The analysis result showed that the ultimate bearing capacity by the formula was much less than the measured value by the static load test. Especially, the result of the parametric study under general shear failure condition showed that the bearing capacity has big difference between each suggested formulas with the variation of the major design parameters. Therefore, the result of this study can be appliable for the future stone column project.

• Journal of Korean Society of Steel Construction
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• v.12 no.3 s.46
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• pp.231-238
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• 2000

There was extreme improvement in the processing result of weld toe, but there is possibility that the fatigue failure occurs from the weld root part where the fatigue strength became low relatively. This study did the fatigue test at the cross rib specimens which implemented a partial penetration weld to improve the fatigue strength of the weld root part. As a result of the fatigue test of the partial penetration weld and the fillet weld specimens, almost the same fatigue strength appeared. Because the fatigue failure began from toe, there was not a reinforcement effect in the weld root part by the partial penetration weld. So, it examined fatigue strength at the partial penetration welding specimens which processed toe to stop the fatigue failure of toe part. As a result, there was big fatigue strength improvement from the partial penetration weld than the fillet weld. Therefore, if fatigue crack occurrence can be restrained from toe, it thinks that the fatigue strength of the root part can improve by the partial penetration weld, after all, it thinks that the overall fatigue life can improve.