• Knowledge Management Research
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• v.12 no.4
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• pp.121-132
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• 2011

Failure, the research object, means situations when goals and their results are different, which has developed presenting various aspects from ancient times and modern times. Failure is a complex concept which essentially requires judgement, and also a relative concept which can be changed depending on how you set up time base and standard. There are four stages for failure study to have been developed from studying failure through historical facts to the approach of organizational theory and it has been studied by looking at the failure of an organization according to different categories such as a developmental stage, a type of business, a period and a course. Compared with success science, failure study has not been studied sufficiently and also the level of its analysis is low. Thus, since lessons of failure tend to repeat themselves instead of being didactically accumulated, there need more studies on this. This thesis identified the main cause of the failure through various studies regarding failure which have been conducted at home and abroad. What the main cause of the failure that more than three studies mentioned have in common was that it occurred because organizations concentrated on the inside without communicating with external environment. The key point of failure study is to analyze failure, utilize it as assets, and create a frame of failure management. This thesis focused on delivering fragmentary knowledge on failure study, but case studies regarding this subject should be done in the future.

• Nuclear Engineering and Technology
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• v.49 no.2
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• pp.327-334
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• 2017

Common-cause failure (CCF) events can significantly impact the availability of safety systems of nuclear power plants. For this reason, the International Common Cause Data Exchange (ICDE) project was initiated by several countries in 1994. Since 1997 it has been operated within the Organisation for Economic Co-operation and Development (OECD)/Nuclear Energy Agency (NEA) framework and has successfully been operated over six consecutive terms (the current term being 2015-2017). The ICDE project allows multiple countries to collaborate and exchange CCF data to enhance the quality of risk analyses, which include CCF modeling. As CCF events are typically rare, most countries do not experience enough CCF events to perform meaningful analyses. Data combined from several countries, however, have yielded sufficient data for more rigorous analyses. The ICDE project has meanwhile published 11 reports on the collection and analysis of CCF events of specific component types (centrifugal pumps, emergency diesel generators, motor operated valves, safety and relief valves, check valves, circuit breakers, level measurement, control rod drive assemblies, and heat exchangers) and two topical reports. This paper presents recent activities and lessons learnt from the data collection and the results of topical analysis on emergency diesel generator CCF impacting entire exposed population.

• Journal of the Korean Operations Research and Management Science Society
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• v.16 no.2
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• pp.164-176
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• 1991

This paper considers the model of a k-out-of-n :G system with non-identical components which are subject to both forced and planned outages. For the forced outages, it assumes that there are the independent and common-cause outage events causing component failures. Then, the objective is to derive the upper and lower bounds on the mean operating time between system failures in the ample-server model. In addtion, the mean system failure times are also considered.

• Journal of the Korean Operations Research and Management Science Society
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• v.17 no.3
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• pp.181-193
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• 1992

This paper shows the model of a consecutive-k-out-of-n :G system with common-cause outages. The objective is to analytically derive the mean operating time between failures for a non-repairable component system. The average failure time of a system and the system availability are also considered. Then, the model is extended to a system with repairable components and unrestricted repair, in which service times are exponentially distributed.

• Nuclear Engineering and Technology
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• v.44 no.5
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• pp.437-452
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• 2012

The Tohoku earthquake (Mw9.0) occurred on March 11, 2011 and caused a large tsunami. The Fukushima Dai-ichi NPP (F1-NPP) were overwhelmed by the tsunami and core damage occurred. This paper describes the overview of F1-NPP accident and the usability of tsunami PRA at Tohoku earthquake. The paper makes reference to the following current issues: influence on seismic hazard of gigantic aftershocks and triggered earthquakes, concepts for evaluating core damage frequency considering common cause failure with correlation coefficient against seismic event at multi units and sites, and concepts of "seismic-tsunami PSA" considering a combination of seismic motion and tsunami effects.

• Journal of Korean Society for Quality Management
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• v.20 no.2
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• pp.94-108
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• 1992

This study involves an experiment for the cognitive experiment design and the human reliability in software engineering. Its overall objectives are to analyze common-cause human domain error and reliability in human-software interaction. A laboratory study was performed to analyze software engineers' task behavior in software production and to identify software design factors contributing to the effects in common cause failure redundancy. Common-cause model and its function were developed, then the main experiment using programming experts was conducted in order to define a new cognitive paradigm, in the aspects of identification, pattern recognition, and behavior domain for human reliability and quality control in software development. The results and analytical procedures developed in this research can be applied to reliability improvement and cost reduction in software development for many applications. Results are also expected to provide guidelines for software engineering quality control and for more effective design of human-software interface system.

• Proceedings of the Korean Nuclear Society Conference
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• 2005.05a
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• pp.1313-1314
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• 2005

• Proceedings of the Korean Nuclear Society Conference
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• 2002.10a
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• pp.193.2-193
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• 2002

• Nuclear Engineering and Technology
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• v.15 no.4
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• pp.229-235
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• 1983

Common Mode Failures (CMFs) have been a serious concern in the nuclear power plant. There is a broad category of the failure mechanisms that can cause common mode failures. This paper is a theoretical investigation of the CMFs on the unavailability of the redundant system. It is assumed that the total CMFs consist of the potential CMFs and the dependent human error CMFs. As the human error dependence is higher, the total CMFs are more effected by the dependent human error. If the human error dependence is lower, the system unavailability strongly depends on the potential CMFs, rather than the mechanical failure or the dependent human error. And it is shown that the total CMFs are dominant factor to the unavailability of the redundant system.

• Journal of Chest Surgery
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• v.15 no.4
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• pp.414-421
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• 1982

200 patients admitted to the Chest Surgery Department of Jeonbug National University Hospital from January, 1974 to December, 1981 were analyzed clinically. The ratio of male to female was 7: 1, which showed male predominance. Distribution of patients according to age disclosed that over half [62%] of the patients was social age between 20 and 49 years. The most common cause of chest trauma was traffic accident [39%], and the next were stab wound, fall down [17.5%], and hit [8.5%] in decreasing order. Common lesions due to chest trauma were as follows; rib fracture [51%], hemopneumothorax, hemothorax, and pneumothorax in decreasing number. The most common cause of rib fracture was traffic accident [50%] and the associated organ injuries were long bone fracture, head injury, spine and pelvic bone fracture, spleen rupture, and liver laceration. Hemothorax, pneumothorax, and hemopneumothorax were treated with insertion of thoracic catheter in 90 cases, pure thoracentesis in 11 cases, and emergency thoracotomy in 11 cases. In flail chest, 6 patients were treated by intramedullary insertion of Kirschner`s wire and the results were good. The incidence of complication was 17%, including atelectasis [11 cases], pyothorax, fibrothorax, pneumonia, and acute respiratory failure. Four patients were died [2%], and the causes were acute respiratory failure in 2 cases, spinal cord injury in one case and head injury in one case.