• Proceedings of the Korean Geotechical Society Conference
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• 2010.03a
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• pp.324-337
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• 2010

For the development of load and resistance factor design, reliability analysis is required to calibrate resistance factors in the framework of reliability theory. The distribution of measured-to-predicted pile resistance ratio was constructed based on only the results of load tests conducted to failure for the assessment of uncertainty regarding pile resistance and used in the conventional reliability analysis. In other words, successful pile load test (piles resisted twice their design loads without failure) results were discarded, and therefore, were not reflected in the reliability analysis. In this paper, a new systematic method based on Bayesian theory is used to update reliability index of driven steel pile piles by adding more pile load test results, even not conducted to failure, into the prior distribution of pile resistance ratio. Fifty seven static pile load tests performed to failure in Korea were compiled for the construction of prior distribution of pile resistance ratio. Reliability analyses were performed using the updated distribution of pile resistance ratio and the total load distribution using First-order Reliability Method (FORM). The challenge of this study is that the distribution updates of pile resistance ratio are possible using the load test results even not conducted to failure, and that Bayesian update are most effective when limited data are available for reliability analysis or resistance factors calibration.

• Journal of Korean Academy of Nursing
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• v.50 no.5
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• pp.671-685
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• 2020

Purpose: The purpose of this study was to develop a Coping Scale for Infertility-Women (CSI-W). Methods: The initial items were based on an extensive literature review and in-depth interviews with seven infertile women. Forty-three items were derived from a pilot survey. Data were collected from 216 women who had experienced intrauterine insemination (IUI) and in-vitro fertilization (IVF) more than once. The data were analyzed to verify the reliability and validity of the scale. Results: Seven factors containing 28 items (four factors containing 17 items for active coping and three factors containing 11 items for passive coping) were extracted from the exploratory factor analysis to verify the construct validity. The four factors of active coping were confrontation, self-control, seeking social support (spouse), and seeking social support (colleagues and experts). The three factors of passive coping were distancing, escape, and avoidance. These items were verified through convergent, discriminant, and concurrent validity testing. The internal consistency reliability was acceptable (active coping: Cronbach's α = .78; passive coping: Cronbach's α = .81). Conclusion: As its validity and reliability have been verified through various methods, the CSI-W can contribute to assessing the coping strategies of infertile women.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.31 no.6
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• pp.351-355
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• 2019

Load resistance factors for the limit state design of vertical caisson breakwaters are presented. Reliability analysis of 16 breakwaters in nationwide ports was conducted to calculate the partial safety factors and they were converted into load and resistance factors. The final load resistance factor was calibrated by applying the optimization technique to the individually calculated load resistance factors. Finally, the breakwater was redesigned using the optimal load resistance factor and verified whether the target level was met. The load resistance factor according to the change of the target reliability level is presented to facilitate the limit state design of breakwater.

• International journal of advanced smart convergence
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• v.8 no.4
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• pp.130-137
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• 2019

We conducted this study to identify the composition factors for consumers' selection attributes of accommodation applications and to identify the differences in the selection attributes perception of accommodation applications based on demographic characteristics and use status. According to the study, 6 factors were derived as the components of the selectivity of accommodation application and were named convenience, interactivity, economic efficiency, transaction reliability, product reliability and informativeness. And the respondents differed in their selection attributes perception of the accommodation application they used. In particular, it was found that the highest perception of informativeness and interactivity, and the lowest perception of product reliability. Finally, there were differences in the selection attributes perception of the accommodation application they used by demographic characteristics and use status. Based on the results of this study, we should strive to derive the effective marketing strategy needed for travel industry-related companies.

• The KSFM Journal of Fluid Machinery
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• v.9 no.2 s.35
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• pp.13-18
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• 2006

This paper was studied to design Process considered flexibility and reliability of suction and discharge valves. Flexibility and reliability of valves are main important factors in compressor valves design. And they are incompatible with efficiency of compressor. In this study, we have performed the optimal design of CO2 compressor valves to consider these factors. At first, we analyzed performance simulation of compressor to obtain optimal flexibility level of valves. From this simulation, we could get some important data at valve design like the optimal natural frequency and the height of retainer. After that we studied to reliability of valves corresponding to optimal flexibility level by finite element method. For each case bending stress and natural frequency were obtained by it. Also we investigated the fatigue stability to obtain optimal valve shape that ensured to reliability.

• Fashion & Textile Research Journal
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• v.8 no.4
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• pp.449-457
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• 2006

The purpose of this study was to investigate perceived service qualities in cosmetics purchasing and, those difference and consumer satisfaction among cosmetics store types. Data were collected from 276 adult females and analyzed by using frequencies, factor analysis, reliability analysis, ANOVA and duncan test utilizing SPSS WIN 10.0. The results showed that consumers perceived service quality such as reliability and responsiveness, product policy, tangibles, store atmosphere policy, business policy, sales policy to cosmetics store. There were significant differences on service quality among cosmetics store types. Consumers using department stores highly perceived factors such as reliability and responsiveness, product policy, tangibles, store and atmosphere policy, but consumers using common cosmetics store lowly perceived these factors. There were significant differences with regard to use effect and pleasure in using to satisfaction among cosmetics store types. Use effect was revealed the highest to consumers purchasing cosmetics in department stores but the lowest in discount stores. Pleasure in using was revealed the highest consumers using department stores but the lowest common cosmetics store.

• Journal of the Korean Society for Railway
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• v.11 no.1
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• pp.75-80
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• 2008

Human factors still play a significant part in many railway accidents. It is well blown that SPAD (Signal Passed at Danger) remains as the single most cause of railway accidents. In this study a stochastic model is developed to quantify SPAD human reliability. This model provides closed-form mathematical expressions into which multiple factors affecting the reliability of man-machine systems can be incorporated. Two basic elements are combined to form the framework for modeling: random signal occurrence and transient human performance characteristics.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.4
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• pp.51-57
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• 1998

It is common to assume identical allowable safety factors in static strength defined by mean stress and in fatigue, defined by stress amplitude. Under the load with asymmetrical cycles the safety factor is not the same. In this paper, with the consideration of unequal allowable safety (actors a general method for estimating fatigue reliability of a machine element under a combined state of stress is derived based on the theory proposed by Prof. Kececioglu and a normal distribution. The calculation of fatigue reliability fur limited life is discussed with example.

• Korean Journal of Adult Nursing
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• v.24 no.3
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• pp.244-252
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• 2012

Purpose: The purpose of the study was to develop a knowledge scale of risk factors for fall among community-dwelling older adults. Further, the validity and reliability of the scale was developed. Methods: A preliminary scale was developed through content validity by five experts and targeted subjects using the CVI (Content Validity Index). Following the establishment of content validity, the scale was used with 359 community-dwelling older adults to further establish both validity and reliability of the scale. Specifically, construct validity using known-group comparison technique, and reliability using Cronbach's ${\alpha}$ were established. Results: After content validity testing, 44 preliminary items were selected. Construct validity was established by known group-comparison, in which scores between the fall and no fall groups were compared. The Cronbach's ${\alpha}$ of the final scale was .83. Conclusion: Reliability and validity of the scale were confirmed. This tool may be used for measuring knowledge of fall risk factor for the community-dwelling older adults.

• Journal of Applied Reliability
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• v.12 no.1
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• pp.25-33
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• 2012

As to display products are made slim, the diameter of aluminum electrolytic capacitor is smaller and the length is longer to be fitted in. These small diameter and long length are pointed as the disadvantageous design factors of the capacitor's life cycle. So, the most electronic makers want to use proven capacitors (or well-known) to secure reliability of the electric products. In this study, we carried out the comparison analysis with two domestic capacitors and one foreign made capacitor. We designated separators, rubber breather and debris as the main factors that effect on the lifetime of capacitors. From the comparison results, we suggested the improvement points of the aluminum electrolytic capacitor.