• Journal of Applied Reliability
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• v.17 no.2
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• pp.112-121
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• 2017

Purpose: The most previous works on designing accelerated life tests (ALTs) are focused on the application of a single stress. Because of the difficulty to obtain the sufficient information in a reasonable duration using single stress only, there is needed in practice to use multiple-stress ALTs frequently. This paper presents new practical plans with two stresses for Weibull distribution. Methods: The four-level practical plans based on rectangle test region are proposed and compared with the corresponding three-level statistically optimal plans. Sensitivity analyses for assumed design parameters and life-stress relationship are conducted. Results: A procedure to choose practical ALT plans is illustrated with a numerical example and guidelines for planning two-stress ALTs are provided. Conclusion: The proposed two-stress ALT plans on practical constraints to assess a quantile of Weibull lifetime distribution at the use condition are efficient and robust.

• Journal of Applied Reliability
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• v.14 no.3
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• pp.182-190
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• 2014

This paper presents new practical accelerated life test plans with different censoring times at three levels of stress for Weibull and lognormal lifetime distributions, respectively. The proposed plans are compared with the corresponding two-level statistically optimal plans and three-level compromise and practical plans. Computational results indicate that new practical plans have been more precise and effective than the existing three-level plans under a constraint of total testing time. In addition, a procedure to determine useful ALT plans is illustrated with a numerical example.

• Transactions of the Korean hydrogen and new energy society
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• v.21 no.4
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• pp.346-353
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• 2010

Hydrogen fueled vehicle was evaluated as one of the next-generation technology that will be able to solve the global warming, depletion of fossil fuel and etc. The practical use of hydrogen fueled vehicle, nevertheless, is being delayed more than expected schedule due to various causes. In order to promote the dissemination of hydrogen fueled vehicle, development status and obstacle factors of practical use for hydrogen fueled vehicles were reviewed and the strategy plans for dissemination promotion were proposed. Hydrogen fueled vehicles are included the hydrogen fuel cell, neat and enriched hydrogen fueled engines. The technicalness, economy, safety, cognizance, system, support and etc were considered in the strategy plans.

• Journal of Korean Society for Quality Management
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• v.24 no.2
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• pp.25-43
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• 1996

This paper presents the optimal and practical constant-stress accelerated life test plans for the lognormal lifetime distribution tinder assumptions of intermittent inspection and Type-I censoring. In an optimal plan, the low stress level and the proportions of test units allocated at each stress are determined under given inspection scheme and number of inspections such that the asymptotic variance of the maximum likelihood estimator of a certain quantile at use condition is minimized. Although the practical plan adopts the same design criterion, it involves three rather than two overstress levels in order to compromise the practical deficiencies of the optimal plan. Computational experiments are conducted to choose an allocation plan and a inspection scheme of the practical plan and to compare with test plans over a range of parameter values.

• Journal of Korean Home Economics Education Association
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• v.31 no.1
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• pp.21-37
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• 2019

This study states a perennial question of "what should we do to heal oneself?" so that teenagers can build the ability to healing themselves at home economics education. The purpose of this study is to development a practical problem focused pedagogical programs and teaching-learning process plans for healing education in the home economics education. For this study, perennial concern and practical problem of healing related to home economics education were identified through the review of the literature related to the Korean and United States' home economics education curricula, and based on the analysis of educational cases in Korea and the United States, a practical-problem-focused program was designed for healing education. Teaching-learning process plans have been developed for practical reasoning instruction based on the designed practical-problem-focused programs and three systems of action. Finally, experts evaluated the developed practical-problem-focused program and teaching-learning process plans for healing education. This study is expected tp serve as the basis for Healing Education in Home Economics Education.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.1B
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• pp.33-40
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• 2008

Intensive rainfalls in wet season (June~September) result in serious flood damage which is about 95% of natural hazard in Korea. Recently, in order to cope with repeated flood hazard, comprehensive flood control plans have been carried out in large basins in Korea. The plans suggest structural alternative plans for flood mitigation as well as non-structural plans. In this study, a practical method using a decision tree was developed to systematically allocate structural facilities for flood control, which maximizes the flood control capacity in a basin. This study also presents a practical guidance to organize structural defensive alternatives for a comprehensive flood control plan in a large basin.

• Communications for Statistical Applications and Methods
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• v.6 no.1
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• pp.143-150
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• 1999

Ko(1998) proposed a procedure to enhance the efficiency of double sampling plans by allowing second-stage sample size and critical region to depend on first-stage evidence using constraint optimization approaches. In this study further developments of such plans by incorporating several practically possible researcher's aims into the optimization are considered. Comparisons are made with the optimal ordinary double sampling plan and also among them It is observed that it is to some extent possible to match the details of the optimization to certain qualitative methodological aims.

• Proceedings of the Korean Society of Computer Information Conference
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• 2013.07a
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• pp.105-108
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• 2013

The commercialization of UCC was already initiated, and there are some successful cases like 'YouTube.' However, the development level of UCC is not mature, stable yet. It's because most of the UCC users are young people and the contents are mainly about humor, funny, minor story. In other words, the practical use of UCC is not totally popularized but partly active. Therefore we want to think out 'how UCC can be utilized by many people and applicable to many industries.' UCC has enough possibility to be advanced, and it will greatly influence the society. In this paper, we will first explain Web 2.0 and the present conditions of online movies. After analyzing the problems and limitation of today, we will propose some suggestions for plans for practical utilization of UCC.

• Journal of Korean Home Economics Education Association
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• v.25 no.4
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• pp.79-98
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• 2013

The purpose of this study was to develop practical problem based teaching-learning plans and to verify its effect on middle school students' self efficacy, ego resilience, and happiness by focusing on the unit of 'Youth's Self Management' in Technology Home Economics. For this study, the contents of twelve different Technology Home Economics middle school textbooks currently in use and a 2007 curriculum guide were analyzed. Based on the problem based question "What do I need to do to control myself better, be mentally healthier, and live a more independent lifestyle?", seven practical problem based teaching-learning plans on 'Youth's Self Management' unit were developed. 7th grade students of "K" middle school living in Gyeonggi province participated in this study. Three control groups were taught through the traditional lecture-based teaching-learning plans while four experimental groups were taught through the practical problem based teaching-learning lesson plans. The effects of lessons on self efficacy, ego resilience and happiness were analyzed using Analysis of Covariance. Significant positive effects on self efficacy, ego resilience and happiness were found in the experimental group of students.

• Journal of Fisheries and Marine Sciences Education
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• v.25 no.5
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• pp.1068-1078
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• 2013

We will discuss the procedures involved in the development of the lesson plans including the various research and analysis approaches, which lead into practical lesson plans based on the 4 sub-categorized subjects analyzed throughout 7 different text books of food hygiene and safety education as followings: Food Hygiene, Personal and Environmental Hygiene, Food Contamination Incidents, Food Poisoning, and Food Safety. Lesson Plans represents STEAM associated education involving the partnerships between business-associated teachers and food educational teachers, focusing on cultivating the students' problem-solving abilities by inducing voluntary participation and critical thinking.