• 한국생활과학회:학술대회논문집
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• 2010.05a
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• pp.180-181
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• 2010

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2005.05a
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• pp.166-166
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• 2005

• Proceedings of the Korea Society of Design Studies Conference
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• 1996.04a
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• pp.1-2
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• 1996

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.1491-1492
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• 2008

This paper investigates life test of LED lighting module using accelerated life test method. Pooly designed LED lighting systems can experience a short life. By knowing the relationship between life and heat, LED system manufacturers can design and build long-lasting systems. In this study, various white LED from several other manufacturer were subjected to life tests at LED lated temperatures for prediction to life of LED lighting systems. Results show that the different LED products have various optical characteristic and different life values.

• Journal of Families and Better Life
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• v.25 no.6
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• pp.95-109
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• 2007

The purpose of this research was to evaluate the effect of ceramic activities on elderly depression and life satisfaction. The research design was based on one group, with a pre and post-test study design. The subjects of this study included twelve elderly from anelderly daytime care center in Yang-san. Instruments used in this research were KGDS (Korea Form of Geriatric Depression Scale) developed by Jung et al., and a form of life satisfaction developed by Youn. A one-hour ceramic activity was offered to participants weekly, for five weeks. The results showed that depression and life satisfaction changed after the ceramic activities. The participants produced results of emotional aspects for demented old people. More specifically and significantly, positive emotions such as pleasure, in-terest, and tranquility were increased, while negative emotions such as anger or depression were significantly decreased through the ceramic activities. Thus, this study's ceramic activities program appeared to have beneficial effects on elderly depression and life satisfaction.

• Structural Engineering and Mechanics
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• v.56 no.2
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• pp.201-221
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• 2015

The fatigue damage problems are frequently encountered in the design of civil engineering structures. A realistic and accurate fatigue life prediction is quite essential to ensure the safety of engineering design. However, constructing a reliable fatigue life prediction model can be quite challenging. The use of traditional deterministic approach in predicting the fatigue life is sometimes too dangerous in the real practical designs as the method itself contains a wide range of uncertain factors. In this paper, a new fatigue life prediction method is going to be proposed where the residual strength is been utilized. Several cumulative damage models, capable of predicting the fatigue life of a structural element, are considered. Based on Miner's rule, a randomized approach is developed from a deterministic equation. The residual strength is used in a one to one transformation methodology which is used for the derivation of the fatigue life. To arrive at more robust results, fuzzy sets are introduced to model the parameter uncertainties. This leads to a convoluted fuzzy based fatigue life prediction model. The developed model is illustrated in an example analysis. The calculated results are compared with real experimental data. The applicability of this approach for a required reliability level is also discussed.

• The Journal of Korean Academic Society of Nursing Education
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• v.17 no.3
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• pp.514-523
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• 2011

Purpose: The purpose of this study was to identify the factors affecting the subjective quality of life among college students from China. Methods: The research design was a descriptive survey design using convenience sampling. Data was collected by using a self-questionnaire completed by 304 Chinese students located in three cities, namely, Seoul, Gangneung, and Seosan. ANOVA, Pearson correlation coefficients and hierarchical multiple regression with the SPSS Win 12.0 Program were used to analyze the data. Results: The average score on subjective quality of life was $3.59{\pm}0.43$. There were significant differences in the subjective quality of life according to length of stay, type of program, and health status. The subjective quality of life had significant negative correlation with acculturative stress and positive correlation with social support. The explained variance for the subjective quality of life was 51.5%. Variables on health status, guilt feelings, other acculturative stress, and social support significantly predicted the degree on subjective quality of life. Conclusion: Findings on this study provide a comprehensive understanding on the subjective quality of life and related factors for Chinese students in Korea. However, further studies with a larger random sample and more detailed research design is necessary.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.5
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• pp.2081-2091
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• 2013

Recently, the demand on the practical application of life-cycle cost effectiveness for design and rehabilitation of civil infrastructure is rapidly growing unprecedently in civil engineering practice. Accordingly, in the 21st century, it is almost obvious that life-cycle cost together with value engineering will become a new paradigm for all engineering decision problems in practice. However, in spite of impressive progress in the researches on the LCC, the most researches have only focused on the Deterministic or Probabilistic LCC analysis approach and general bridge at design stage. Thus, the goal of this study is to develop a practical and realistic methodology for the Life-Cycle Cost LCC-effective optimum decision-making based on reliability analysis of bridges at design stage. The proposed updated methodology is based on the concept of Life Cycle Performance(LCP) which is expressed as the sum of present value of expected direct/indirect maintenance costs with expected optimal maintenance scenario. The updated LCC methodology proposed in this study is applied to the optimum design problem of an actual highway bridge with Cable Stayed Bridges. In conclusion, based on the application of the proposed methods to an actual example bridge, it is demonstrated that a updated methodology for performance-based LCC analysis proposed in this thesis, shown applicably in practice as a efficient, practical, process LCC analysis method at design stage.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.1262-1267
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• 2007

The korea railway design has been developed by change of the society and culture through the consideration of the history of railway. Accordingly there contribute in the development of the korea railway design by analyzing the trend according to the changes o the korea railway design and the changes of the life environment in this paper. As dividing the design by period according to the changes of life environment into the internal and external nation, there are to analyze the development history of the korea railway design accordingly the railway and the style's change, to confirm into the design applied in society and culture needs, and to analyze by a year in changes of the environment and the korea railway design history from the 1800's to 2005.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2001.04a
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• pp.128-136
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• 2001

This paper presents an optimum deck and girder system design for minimizing the life-cycle cost (LU) of steel box girder bridges. The problem of optimum LCC design of steel box girder bridges is formulated as that of minimization of the expected total LCC that consists of initial cost, maintenance cost, expected retrofit costs for strength, deflection, and crack. To demonstrate the effect of LCC optimum design of steel box girder bridges, the LCC optimum design is compared with conventional design method for steel box girder bridges design. From the numerical investigations, it may be positively stated that the optimum design of steel box girder bridges based on LCC will lead to more rational, economical and safer design.