• Industrial Engineering and Management Systems
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• v.9 no.1
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• pp.54-59
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• 2010

A two-plan sampling system is proposed for a failure-censored life testing when the lifetime follows a Weibull distribution with known shape parameter. The proposed sampling system is based on a switching rule, for switching between the tightened and the normal inspection levels when lots are submitted for inspection in the order of production or in some other systematic way. The design parameters of the proposed sampling system are determined by the two-point approach considering the producer's risks and the consumer's at the specified acceptable reliability level and the lot tolerance reliability level, respectively. It has been observed that the proposed system requires only a single failure for the observation.

• Nuclear Engineering and Technology
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• v.50 no.8
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• pp.1210-1216
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• 2018

Site or multi-unit (MU) risk assessment has been a major issue in the field of nuclear safety study since the Fukushima accident in 2011. There have been few methods or experiences for MU risk assessment because the Fukushima accident was the first real MU accident and before the accident, there was little expectation of the possibility that an MU accident will occur. In addition to the lack of experience of MU risk assessment, since an MU nuclear power plant site is usually very complex to analyze as a whole, it was considered that a systematic method such as probabilistic safety assessment (PSA) is difficult to apply to MU risk assessment. This paper proposes a new MU risk assessment methodology by using the conventional PSA methodology which is widely used in nuclear power plant risk assessment. The logical failure structure of a site with multiple units is suggested from the definition of site risk, and a decomposition method is applied to identify specific MU failure scenarios.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.881-895
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• 2011

Seoul Metro railway facilities' inspection and maintenance tasks cause failure analysis, but if there is trouble the diverse cause investigation and the systematic analysis and management among broken facilities, related facilities and components fell short and the conditions are different. And, excess and insufficiency, under inspection and maintenance, is being raised regardless of the introduction year and the operating environment including the number of use by applying the same facilities in the uniform inspection cycle. In this study, we will analysis systematically facility system information, failures, operational status, performance, fault and maintenance information resulting from the maintenance management of railway facilities and derive the relationship between associated equipment and its components. In addition, optimizing the inspection and the maintenance cycles of railway facilities, we will improve the reliability of operation. Considering the probability of risk, it is possible to predict the occurrence of accidents or faults and to minimize the frequency of breakdown by pre-inspection maintenance. Finally, This paper is to introduce the content of constructing the Seoul Metro RCM-based failure analysis system for railway facilities to support the optimal continuance of operation status of equipments and the securement of the safe operation of vehicles.

• Journal of The Korean Society of Agricultural Engineers
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• v.57 no.3
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• pp.101-108
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• 2015

The purpose of this study was to evaluate the safety of the small reservoir, which is distributed in a rural area, based on systemic reliability. It has been estimated that safety of respective reservoir the calculation of failure probability for individual reservoirs can evaluate the safety of the reservoir of the study area. The change of safety for watershed could be figured out as that result. Probability of failure was increased from $3.90{\times}10^{-5}$ to $1.35{\times}10^{-4}$ in Naesu-inpyung reservoir, from $1.33{\times}10^{-5}$ to $4.77{\times}10^{-5}$ in Buyeon reservoir and from $4.24{\times}10^{-5}$ to $2.55{\times}10^{-2}$ in Dalakmal respectively. From the results, the collapse of the upper stream reservoir was analyzed qualitatively that may affect the safety of the reservoir on the downstream area.

• Journal of Computing Science and Engineering
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• v.2 no.2
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• pp.200-219
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• 2008

The effective management of uncertainty is one of the most fundamental problems in medical decision making. According to the literatures review, most medical decision models rely on point estimates for input parameters. However, it is natural that they should be interested in the relationship between changes in those values and subsequent changes in model output. Therefore, the purpose of this study is to identify the ranges of numerical values for which each option will be most efficient with respect to the input parameters. The Nonhomogeneous Poisson Process(NHPP) was used for describing the behavior of aging chronic diseases. Three kind of failure models (linear, exponential, and power law) were considered, and each of these failure models was studied under the assumptions of unknown scale factor and known aging rate, known scale factor and unknown aging rate, and unknown scale factor and unknown aging rate, respectively. In addition, this study illustrated developed method with an analysis of data from a trial of immunotherapy in the treatment of chronic Granulomatous disease. Finally, the proposed design of Bayesian value of information analysis facilitates the effective use of the computing capability of computers and provides a systematic way to integrate the expert's opinions and the sampling information which will furnish decision makers with valuable support for quality medical decision making.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.37 no.3
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• pp.16-23
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• 2014

Most of metal cutting and processing companies are going through the difficulties such as frequent downtime and high failure rates by missing times to replace parts of CNC equipment. The reason is that the correct operation times of expensive CNC equipment can't be calculated. In this paper, to solve this problem, we try to construct the intelligent production information system for a case company and analyze its expected effects. The effects are as follows. First, it saves money about 3 million won each year during the useful life of three years by reducing downtime and failure rates, and increasing production rates etc. Second, it makes easily find and fix the cause of faulty through traceability of the production process, and enables to perform a systematic facility management through the calculation of reliable equipment's overall efficiency. This case can be easily applied in similar industries, and will contribute greatly to enhancing the competitiveness of related industries.

• The Journal of Korean Academic Society of Nursing Education
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• v.16 no.1
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• pp.150-155
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• 2010

Purpose: The purpose of this study is to develop evidence-based nursing practice guidelines for hemodialysis in the renal failure patients with risk of bleeding and to evaluate the guidelines by applying it to the practice. Method: Referring to the SIGN, the first draft for guidelines was developed based on the advices and recommendations obtained from the procedure of critical literature analysis. Then, the draft was modified by the procedures of the expert group evaluation and pilot application to the practice. The final draft was evaluated by the expert group using AGREE instrument. Result: The first draft of guidelines was developed through 8 stages of process and was evaluated by seven experts in terms of the appropriateness, applicability, and effectiveness using a 9 point scale. The mean score of 11 items was 7.90 or above. The quality of the final draft was evaluated by 5 experts using the AGREE instrument. The mean standard score was 73.0% or above in the 19 items. Conclusion: The clinical guidelines developed by this research can be utilized as systematic and scientific guidelines for hemodialysis in the renal failure patients with risk of bleeding. In addition, the research can contribute to improving care services.

• Herbal Formula Science
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• v.24 no.3
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• pp.233-242
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• 2016

Objective : Chronic renal failure(CRF) is defined as a permanent reduction in glomerular filtration rate(GFR), resulting in Structural and functional abnormalities. The purpose of this thesis is to report the improvement of a CRF stage4 on stroke patient through integrative medicine therapy.Methods : We treated the patient with herbal medication(Sibjeondaebo-tang gagambang), acupuncture and moxibustion as well as Western medication. We measured the Creatinine, BUN, eGFR in the serum and observed clinical symptoms During 4monthsResult : After treatment, the level of BUN and Creatinine was decreased and eGFR was increased. And the symptoms of CRF(edema, anorexia, general weakness) were improved.Conclusion : This study suggests that Integrative Medicine Therapy is effective in the treatment of CRF symptoms. In the future, for the effective management of CRF, It is considered necessary to build a systematic integrative medicine therapy.

• Journal of the Korean Society of Safety
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• v.31 no.3
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• pp.102-108
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• 2016

As a range of accidents happen frequently in our society due to safety insensitivity, researches on individual psychological characteristics related to safety behavior and on safety education are increasing. However, safety behavior research that targets university students as potential employees remains rare. Therefore, this research investigates individual characteristics and psychological factors that affect safety behaviors of university students. Research participants were 131 university students (80 males, 51 females) from the Gyeonggi-do and Chungnam areas. Psychological characteristics (self-regulation, cognitive failure, conscientiousness, and emotional stability) were included as variables that may predict university students' safety behaviors (habits, compliance, mistakes, and violations). The major findings of the study are as follows. Stepwise regression analysis showed conscientiousness was a major predictor explaining safety habits and safety compliance; Cognitive failure and emotional stability were main predictors explaining safety mistakes, and self-regulation was a major predictor explaining safety violations. These findings suggest that development of proper education programs focusing on individual characteristics would allow systematic improvement of safety behaviors of university students.

• Journal of Yeungnam Medical Science
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• v.38 no.4
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• pp.361-365
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• 2021

Stroke patients have reduced aerobic capacity. Therefore, intensive structured exercise programs are needed. We report the case of a patient with stroke and cardiac disease who underwent early inpatient cardiac rehabilitation (CR). A 38-year-old male patient with atrial fibrillation, heart failure, and cerebral infarction underwent a symptom-limited exercise tolerance test (ETT) without any problems on day 45 after admission. He completed a 2-week inpatient program and an 8-week home-based CR program. Follow-up ETT showed increased exercise capacity. The present case might be the first to report a safely performed CR program in a patient with stroke and cardiac comorbidity in Korea. Systematic guidance is needed for post-stroke patients to receive safe and effective CR for the secondary prevention of stroke and cardiovascular risk.