• Journal of Korean Society for Quality Management
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• v.13 no.2
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• pp.8-12
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• 1985

We study the Bayes estimation procedure of ${\theta}=P_r$=(Y < X) when the experiment is terminated before all of the items on the test have failed and the failed items are partially replaced. Comparisons with the M.L.E., M.V.U.E. and Bayes estimator are made through Monte Carlo simulation.

• Journal of Korean Foot and Ankle Society
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• v.19 no.2
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• pp.47-50
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• 2015

Microfracture procedure has been widely recognized as the primary surgical treatment for an osteochondral lesion of the talus. However, if symptoms persist after initial surgery, selection of a secondary procedure can be difficult. The author desciribes the advantage and value of autologous osteochondral transplantation as a secondary procedure after failed microfracture for osteochondral lesion with a review of sevral previous published articles.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.799-802
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• 1995

Whale helical gears is used to transmit motion between parallel shafts, the shaft bearings are subjected to both radial and thrust loads. The reliability and life analysis are based on the two-parameter Weibull disribution lives of the component gears and bearings. Two methods of estimating the time between gear system overhauls and the number of replacement components needed were presented. The first method assumes replacement of all components during an overhaul of a failed gear system. the second method assumes replacement of failed comonents only. Renewal theory was presented to estimate the number of comonent replacements in a gear system for both methods.

• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.430-433
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• 1999

Woo[8]proposed dual-token based fault-tolerant scheduling algorithm in multiprocessor environment for resolving the problem of old systems that have a central dispatcher processor. However, this algorithm does not present token allocation algorithm in detail when central dispatcher processor has failed. In this paper, we propose a fault detection algorithm and processor selection algorithm for token allocation when central dispatcher processor has failed.

• Proceedings of the Korean Reliability Society Conference
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• 2000.11a
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• pp.387-395
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• 2000

Circular consecutive-k-out-of-n:F system when the failure of component is dependent is studied. We assume that the failure of a component in the system increase the failure rate of the survivor which is working just before the failed component. In this case, a mean time to failure (MTTF), a average failure number of the system, and the expected cost per unit time are obtained. Then the minimum number of consecutive failed components to cause system failure to minimize the expected cost per unit time is determined as searching paths to system failure. And various numerical examples are studied.

• 한국데이터정보과학회:학술대회논문집
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• 2002.06a
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• pp.89-95
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• 2002

This paper considers the problem of estimating paramaters of the bivariate exponential distribution with a loaction parameter for a two-component shared parallel system using component data from system-level life test terminated at the time of the prespecified number of system failure. In the system-level life testing, there are three patterns of failure types; 1) both component failed 2) both component censored 3) one is failed and the other is censored. In the third case, we assume that the failure time might be known or unknown. The maximum likelihood estimators are obtained for the case of known/unknown failure time when the other component is censored.

• Journal of Korean Society for Quality Management
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• v.19 no.2
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• pp.78-85
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• 1991

In this paper, an inspection and replacement policy in a redundant system is considered. It is assumed that the state of the redundant system is known by inspection. When the system is inspected, it is preventively replaced only if the number of failed units exceeds the predetermined limit. Otherwise, the system is inspected after a inspection interval which depends on the number of failed units. We obtain the optimal number of redundant units, inspection intervals and replacement limit minimizing the expected cost rate.

• Nuclear industry
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• v.4 no.2 s.18
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• pp.28-39
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• 1984

• Journal of the korean academy of Pediatric Dentistry
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• v.43 no.1
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• pp.51-59
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• 2016

The purpose of the present retrospective study was to analyze gender, age, awareness, etiology, and treatment choice in patients with failed eruption of the mandibular first molar. Radiographic material and dental records from 67 patients with 74 mandibular first molars with failed eruption treated during the years 2001-2014 were evaluated. As results, the prevalence of mandibular first molar with failed eruption was higher in males than females, and the average awareness age was 9.19 years old. The most common etiological cause was unknown, and the next most common causes were abnormal eruption pathway and odontogenic tumor in order. In this study, it is suggested that more dental education to children about the time of eruption of permanent tooth is required, and the importance of regular dental check-ups is emphasized during mixed dentition.

• Korean Journal of Health Education and Promotion
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• v.21 no.1
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• pp.137-151
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• 2004

Objectives： This study aims to investigate the psychological factors associated with abstention following a smoking cessation program, and to suggest useful information for those who want to stop . smoking and health practitioners who help them Methods： Participants were 73 smokers (65 males, 8 females) that participated in a hospitalized smoking cessation program, whose mean age was 44.89 (SD＝9.61). Participants completed questionnaires and psychological tests including： Demographic sheet, Eysenck's Personality Questionnaire, Multidimensional Coping Scale, Fagerstrom Test for Nicotine Dependence, and Jerusalem and Schwarzer's Self-Efficacy Scale. To identify whether the subjects abstained or not and to encourage them to abstain, the researcher called them on the telephone once a week for three months. After three months, they were contacted every other week till six months passed since they had left the smoking cessation program Tthey were THEN contacted once a month for another six months. The data was analyzed by using ANCOVAs with SPSS 10.0 for Windows. Results： 42 (57.5％) out of 73 abstained for one month and 26 (35.6％) abstained for one year. People who failed to abstain within a month showed a higher psychoticism and introversion personality trait than those who abstained for one month, while people who abstained for one month were coping actively in most situations, showed a higher self-efficacy and lower nicotine dependence than those who failed to abstain within a month, and people who failed to abstain within a year showed a higher psychoticism than those who abstained for one year. While people who abstained for one year were coping actively, obstinate, and interpreting positively most situations, they showed a higher self-efficacy than those who failed to abstain within a year. Conclusion： These findings reiterate the roles of personality, self-esteem, nicotine dependence in smoking and suggest the roles for smoking cessation. And it was found the roles of coping styles ,in smoking cessation. It might help smokers who want to stop smoking and health practitioners who help them