• Journal of Korean Institute of Industrial Engineers
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• v.34 no.1
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• pp.23-31
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• 2008

This paper presents accelerated degradation test plans considering adoption of tightened critical values. Under arandom coefficient degradation rate and log-linear acceleration models, the asymptotic variance of an estimatorfor a lifetime quantile at the use condition as the optimization criterion is derived where the degradation ratefollows a lognormal and Reciprocal Weibull distributions, respectively and then the low stress level andproportions ofunits allocated to each stress level are determined. We also show that the developed test plans canbe applied to the multiplicative model with measurement error.

• Journal of Applied Reliability
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• v.5 no.1
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• pp.167-180
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• 2005

Design of a degradation test without replacement is considered based on tightened critical value to reduce the evaluation testing time. The sample size, number of inspections, and the critical values are determined to assure the same probability of acceptance when the testing time is reduced to some degree. Photo-diode balance of an optical pickup is analyzed as a case study.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.31 no.4
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• pp.153-161
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• 2008

신뢰성 평가 시험은 종종 성능 평가에 장기간의 시간이 요구되며, 전체 생산비용까지 증가시키는 문제점을 안고 있다 스트레스를 이용한 가속수명시험은 제품의 신뢰성 고장과 밀접한 관련이 있는 고장 메커니즘의 촉진을 통해 고장에 이르는 기간을 단축함으로써 신뢰성 평가의 효율성을 도모할 수 있다. 본 연구에서는 이러한 스트레스 가속 시험에 빈도가속(Usage-Rate Acceleration) 또는 판정가속(Tightening Critical-Values) 등을 결합하여 한층 높은 가속효과를 도모하는 방법을 제안하고, 국내에서 생산되고 있는 2차 전지 제품에 대한 실제 시험 사례분석을 통해 결합된 가속방법의 효과를 실증적으로 보여주고 있다.

• Korean Journal of Social Welfare Studies
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• v.47 no.3
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• pp.85-111
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• 2016

This study aims to analyse major changes of Mental Health Promotion and Welfare Service Support Act(MHPWSSA) and critically discuss these changes based on the major discourses on Mental Health Act revision. For this purposes this study reviewed literatures and government reports to understand human rights discourses, welfare discourses, and prevention discourses. Secondly, the major changes of MHPWSSA were analysed and discussed based on those discourses. This study found that MHPWSSA defined the concept of people with mental disorders narrowly, tightened the involuntary admission procedures, introduced welfare service support provisions and mental health promotion provisions. But this study shows that the new legislation may well be criticised due to neglect of the concept of disability and people with psychiatric disability, involuntary admission without mental capacity assessment, neglect of the basic values and principles of self determination and independent living common in welfare of the persons with disability. And the new legislation may be criticised due to overuse of the concept of mental health promotion as encompassing promotion, prevention, treatment and rehabilitation.