• Journal of Power System Engineering
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• 제21권1호
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• pp.43-49
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• 2017

This work aims to investigate on the low cycle fatigue life assessment, which is adopted on the strain-life relationship, or better known as the Coffin-Manson relationship, and also the strain energy density-based model. The low cycle fatigue test results of Alloy 617 weldments under $900^{\circ}C$ have been statistically estimated through the Coffin-Manson relationship according to the provided strain profile. In addition, the strain energy density-based model is proposed to represent the energy dissipated per cycle as fatigue damage parameter. Based on the results, Alloy 617 weldments followed the Coffin-Manson relationship and strain energy density-based model well, and they were compatible with the experimental data. The predicted lives based on these two proposed models were examined with the experimental data to select a proper life prediction parameter.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 한국해양공학회 2000년도 춘계학술대회 논문집
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• pp.40-45
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• 2000

Presented are the estimation of the probability distribution of fatigue crack growth life and reliability assessment of structures by simulating material resistance to fatigue crack growth along a crack path. The material resistance is treated as a Weibull stochastic process. A non-Gaussian stochastic fields simulation method proposed by Shimozuka, et al is applied with the statistical data obtained experimentally. Test results are obtained for $\Delta$K constant amplitude load in tension with stress ratio of R=0.2 and three specimen thicknesses of 6, 12 and 18mm. This simulation method is useful to estimate the probability distribution of fatigue crack growth life and the smallest life.

• Journal of Ocean Engineering and Technology
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• 제14권4호
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• pp.73-78
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• 2000

Presented are the estimation of the probability distribution of fatigue crack growth life and reliability assessment of structures by simulating material resistance to fatigue crack growth along a crack path. The material resistance is treated as a Weibull stochastic process. A non-Gaussian stochastic fields simulation method proposed by shimozuka, et al is applied with the statistical data obtained experimentally. Test results are obtained for $\delta K$ constant amplitude load in tension with stress ratio of R=0.2 and three specimen thicknesses of 6,12 and 18mm. This simulation method is useful to estimate the probability distribution of fatigue crack growth life and the smallest life.

• Journal of Applied Reliability
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• 제11권4호
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• pp.331-342
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• 2011

The transmission of tracked vehicles performs complex functions as steering, shifting, braking, etc. and the system level life time has been a key influenced by the number of sub-parts like as gear assembly, torque converter, clutches, bearings and so on. In particular, the mechanical type steering system in tracked vehicle has impact shock torques in steering shift and those kind of shock torques can effect on the durability of many sub-parts in power train system. The field failure modes of gear assembly, steering assembly and the bearings of output shaft appear as a very complex phenomenon. In this study, the actual failure, which may occur in field, of the transmission was investigated comprehensively and that the endurance test on the resulting output shaft bearing failure analysis and life assessment was performed. Life time test method used in this study, developed for the purpose of the internal usage, and under these testing techniques the impact of the each bearing damage, which used in tracked vehicle transmission left / right outputs of different structures, was analyzed.

• Proceedings of the KIEE Conference
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• 대한전기학회 2007년도 Techno-Fair 및 추계학술대회 논문집 전기물성,응용부문
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• pp.216-217
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• 2007

This paper represents the reliability assessment on the mould type combined transformer used in the distribution system by electrical tests. For the reliability assessment, we had tested lightning impulse test, short-circuit withstand capability test, electrical accelerated life test and so on to the mould type combined transformer of Young-Hwa Industrial Electric Co., Ltd.

• Journal of the Korea Institute of Information and Communication Engineering
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• 제16권8호
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• pp.1711-1716
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• 2012

Vocational rehabilitation is defined as a process which helps people with disabilities to maintain life of non-disabled people and vocational assessment is a part of it. Traditionally, vocational assessment is performed through using of assessment tools or vocational counseling, but assessment tools are very expensive and we should move to the facilities for the disabled. It is very efficient to apply vocational assessment to people with disabilities using the smart phones which users are expected to surpass thirty million in 2012, because it enables them to access anytime and anywhere. In this paper, we design and implement the mobile aptitude test system on android smart phone OS for people with disabilities. We develop the mobile aptitude test system using the Holland Test which is the assessment tool of career guidance and counseling.

• The Journal of Korean society of community based occupational therapy
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• 제7권1호
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• pp.49-57
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• 2017

Objective : The purpose of this study to create a translation of Life Space Assessment(LSA) for elderly, which was then tested for content related validity and understanding test. Methods : The translation and content validation process involved direct and backward translation, and the collection of content-related evidence from 6 expert panels and 13 clinician panels. A content validity indices (CVI), means, and standard deviations were used for the analysis of the content validity. Results : The results of the comparison between the original LSA and the Korean LSA with the expert panels were I-CVI showed a very high value of .93. and 1.00, and S-CVI/Ave 0.99. The results of the understanding test were showed a very high value of .92 and 1.00, and S-CVI/Ave 0.97. Conclusion : Korean LSA showed content related validity and understanding test, and illustrated the applicability of LSA in a Korean clinical setting. The results showed LSA can be used a useful tool for evaluating the community mobility of elderly.

• Women's Health Nursing
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• 제22권3호
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• pp.182-190
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• 2016

Purpose: This study was done to identify effects of cognitive function and cancer coping on quality of life among women with breast cancer treated with antineoplastic agents. Methods: The study was correlational research and participants were 145 women with breast cancer who had received antineoplastic agents. Data were collected from October to November, 2015 via online replies. Cognitive function was measured with the Functional Assessment of Cancer Therapy-Cognitive Function Version-3 (FACT-Cog), cancer coping, with the Korean Cancer Coping Questionnaire (K-CCQ), and quality of life with the Functional Assessment of Cancer Therapy-Breast Version-4 (FACT-B). Data were analyzed using descriptive statistics, t-test, ANOVA, $Scheff{\acute{e}}$ test, ANCOVA, Bonferroni test, partial correlation coefficient, and hierarchical multiple regression with SPSS 21. Results: Cognitive functions, total individual coping, and interpersonal coping explained 42% of quality of life. Cognitive function (${\beta}=.35$, p<.001) was the best predictor of quality of life, followed by total individual coping (${\beta}=.34$, p<.001), and interpersonal coping (${\beta}=.26$, p<.001). Conclusion: Results indicate that cognitive function and cancer coping are meaningful factors for quality of life among breast cancer survivors. Therefore when developing intervention programs for these women, content on cognitive function and coping skills as well as coping resources should be included.

• Journal of Welding and Joining
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• 제32권3호
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• pp.102-107
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• 2014

Boiler equipment in power plant is always being operated in harsh conditions and severely exposed to the extreme environment of high temperature. Therefore periodically the state of devices should be checked, diagnosed, and analyzed to ensure the reliability of the equipment. Traditionally, such a diagnosis is based one or two physical properties of the sample taken from the equipment like hardness, microstructure, etc.. However, to enhance the confidence of the diagnosis, it is necessary to synthesize those properties together. This paper is to propose such a synthetic procedure for SA213-T12(1Cr-0.5Mo) which was developed to be used in $565^{\circ}C$ below condition. Creep test and accelerated degradation test were performed simultaneously, and the physical properties such as microstructure, tensile strength, yield strength, hardness, and indentation properties were measured. This paper proposes a method of determining the remaining life by quantitative comparison. It will provide the basis of evaluating life assessment more objective and reliable.

• Journal of Welding and Joining
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• 제31권5호
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• pp.26-34
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• 2013

Boiler equipment in power plant is always being operated in harsh conditions and severely exposed to the extreme environment of high temperature. Therefore periodically the state of devices should be checked, diagnosed, and analyzed to ensure the reliability of the equipment. Traditionally, such a diagnosis is based one or two physical properties of the sample taken from the equipment like hardness, microstructure, etc.. However, to enhance the confidence of the diagnosis, it is necessary to synthesize those properties together. This paper is to propose such a synthetic procedure for T23 which was developed to be used in $569^{\circ}C/596^{\circ}C$ condition. Creep test and accelerated degradation test were performed simultaneously, and the physical properties such as microstructure, tensile strength, yield strength, hardness, and indentation properties were measured. This paper proposes a method of determining the remaining life by quantitative comparison. It will provide the basis of evaluating life assessment more objective and reliable.