• Journal of Korean Institute of Industrial Engineers
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• v.33 no.1
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• pp.61-69
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• 2007

In a large complex system, maintenance priorities for the failed components are important to maintain the sys-tern reliability at required level. Commonly used methods of determining maintenance priorities are based onranking the failed components by using reliability importance measures such as Birnbaum reliability importance,risk achievement worth and F-V importance, etc. In the preceding works, maintenance priorities for the failedcomponents are determined by using such existing measures, In this study, a new method of determining main-tenance priorities, which utilizes the joint reliability importance is proposed. By investigating the sign of thejoint reliability importance, maintenance priorities obtained by the existing methods are adjusted to yield new re-vised priorities. The revised maintenance priorities are shown to be more effective than the existing ones fromthe standpoint of the speed of system recovery, Effectiveness of the proposed method is illustrated by numericalexamples.

• Journal of the Korea Safety Management & Science
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• v.14 no.1
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• pp.225-233
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• 2012

The research discusses interrelationship of structural and reliability importance measures which used in the probabilistic safety assessment. The most frequently used component importance measures, such as Birnbaum's Importance (BI), Risk Reduction (RR), Risk Reduction Worth (RRW), RA (Risk Achievement), Risk Achievement Worth (RAW), Fussel Vesely (FV) and Critically Importance (CI) can be derived from two structure importance measures that are developed based on the size and the number of Minimal Path Set (MPS) and Minimal Cut Set (MCS). In order to show an effectiveness of importance measures which is developed in this paper, the three representative functional structures, such as series-parallel, k out of n and bridge are used to compare with Birnbaum's Importance measure. In addition, the study presents the implementation examples of Total Productive Maintenance (TPM) metrics and alternating renewal process models with exponential distribution to calculate the availability and unavailability of component facility for improving system performances. System state structure functions in terms of component states can be converted into the system availability (unavailability) functions by substituting the component reliabilities (unavailabilities) for the component states. The applicable examples are presented in order to help the understanding of practitioners.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05a
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• pp.838-843
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• 1998

Risk importance measures are widely wed to rank risk contributors in risk-based applications. Typically, Fussell-Vesely (F-V) importance and risk achievement worth (RAW) are used in the component importance raking for the reliability centered maintenance (RCM) analysis of safety system in nuclear power plants (NPPs). This study was performed as part of feasibility study on RCM for domestic NPPs, which is focused on the component importance ranking approach the maintenance recommendation. The approach of modulizing faulting tree basic events was applied in the simplification process of the PSA model and the validity of the approach was evaluated As a result of the case study, this paper included the importance and the maintenance recommendations for the safety-related equipments associated with safety injection and containment spray in large loss of coolant accident sequences.

• Journal of Korean Academy of Nursing
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• v.48 no.1
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• pp.12-25
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• 2018

Purpose: This study was performed to develop the Job Satisfaction Scale for Clinical Nurses (JSS-CN) and verify its validity and reliability. Methods: A preliminary 42-item version of the JSS-CN was developed through literature reviews and in-depth interviews. The draft scale was developed using thirty-seven items selected following content validity evaluation. Finally, thirty-three items with response options on a 5-point Likert scale were selected based on internal consistency reliability and construct validity. Subsequently, the test-retest reliability and convergent validity of the JSS-CN were verified. Results: Six factors, namely, recognition from the organization and professional achievement, personal maturation through the nursing profession, interpersonal interaction with respect and recognition, accomplishment of accountability as a nurse, display of professional competency, and stability and job worth, were identified, which explained 59.7% of the total variance. The JSS-CN's Cronbach's ${\alpha}$ for the total scale was .95, and the intra-class correlation coefficient was .90. The correlation coefficient between the scores of the JSS-CN and Slavitt's scale was .75, and that between the JSS-CN and job performance was .53. Conclusion: Results showed that the JSS-CN has good reliability and validity. Therefore, it is concluded that the JSS-CN could be a useful tool for the measurement of the job satisfaction of clinical nurses in Korea.