• Earthquakes and Structures
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• v.8 no.2
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• pp.443-462
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• 2015

Some model building codes stipulate that the design displacement of a building can be computed using the elastic static analysis results multiplied by the deflection amplification factor, $C_d$. This approach for estimating the design displacement is essential and appealing in structural engineering practice when nonlinear response history analysis (NRHA) is not required. Furthermore, building codes stipulate the consideration of accidental torsion effects using accidental eccentricity, whether the buildings are symmetric-plan, or asymmetric-plan. In some model building codes, the accidental eccentricity is further amplified by the torsional amplification factor $A_x$ in order to minimize the discrepancy between statically and dynamically estimated responses. Therefore, this warrants exploration of the reliability of statically estimated design displacements in accordance with the building code requirements. This study uses the discrepancy curves as a way of assessing the reliability of the design displacement estimates resulting from the factors $C_d$ and $A_x$. The discrepancy curves show the exceedance probabilities of the differences between the statically estimated design displacements and NRHA results. The discrepancy curves of 3-story, 9-story, and 20-story example buildings are investigated in this study. The example buildings are steel special moment frames with frequency ratios equal to 0.7, 1.0, 1.3, and 1.6, as well as existing eccentricity ratios ranging from 0% to 30%.

• Journal of Korean Academy of Nursing Administration
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• v.10 no.2
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• pp.175-184
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• 2004

Purpose: The purpose of this study was to develop a nursing organization culture measurement tool and to test the validity and reliability of the tool. Method: This study conducted in three phases. In phase 1, theoretical framework choice, Phase 2, measurement items selection, Phase 3, testing of validity and reliability. In order to test validity and reliability of the measurement, data were collected from 915 nurses, working in the 22 hospitals with more 500 beds. The data obtatined were analyzed by SPSS-Win 10.0 program using percentages, Factor Analysis, Cronbach's alpha Coefficients. Result: As a result of the study, nursing organization culture measurement scale was consisted of 20 items, 4 factors. 4 factor explained 60.54% of the total variance, and the Cronbach's alpha of this scale was .8829. Conclusions: The Study supports the validity and reliability of the scales. Therefore, this scale can be effectively utilized for the evaluation of nursing organization culture in hospital setting.

• Research in Community and Public Health Nursing
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• v.28 no.4
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• pp.366-374
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• 2017

Purpose: The purpose of this study was to evaluate the validity and reliability of the Korean Version of the Nurses' Self-Concept Instrument (NSCI) geriatric hospital nurses in Korea. Methods: Bilingual nursing professionals performed translation and back-translation. Reliability and validity of the content and construction of the instrument were confirmed. Internal consistency reliability was determined. Construction and concurrent validity were verified using factor analysis and correlation coefficients. Results: The total 14 items for the Korean version of the Nurses' Self-Concept Instrument (NSCI) were retained through item analysis. In explanatory factor analysis, four subcategories were proposed with their names of each factor: 'Leadership', 'Staff relation', 'Knowledge', and 'Care'. The four factors accounted for 78.81% of the variances. The Cronbach's ${\alpha}$ regarding internal consistency were .77~.91 for the NSCI subscales. Correlation among four subcategories ranged .62~.84. Conclusion: The findings show that the Korean version of the Nurses' Self-Concept Instrument is reliable and valid for measuring professional Self-Concept of geriatric hospital nurses in Korea.

• Journal of Electrical Engineering and Technology
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• v.12 no.4
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• pp.1397-1405
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• 2017

As the introduction of wind power is steadily increasing, negative effects of wind power become more important. To operate a power system more reliable, the system operator needs to recognize the maximum required capacity of available generators for a certain period. For recognizing the maximum capacity, this paper proposes a methodology to determine an optimal reserve requirement considering wind power, for the certain period in the mid-term perspective. As wind speed is predicted earlier, the difference of the forecasted and the actual wind speed becomes greater. All possible forecast errors should be considered in determining optimal reserve, and they are represented explicitly by the proposed matrix form in this paper. In addition, impacts of the generator failure are also analyzed using the matrix form. Through three main stages which are the scheduling, contingency and evaluation stages, costs associated with power generation, reserve procurement and the usage, and the reliability cost are calculated. The optimal reserve requirement is determined so as to minimize the sum of these costs based on the cost/reliability analysis. In case study, it is performed to analyze the impact of wind power penetration on the reserve requirement, and how major factors affect it.

• Structural Engineering and Mechanics
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• v.47 no.2
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• pp.167-183
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• 2013

Methods for estimating structural reliability using probability ideas are well established. When the residual ultimate strength of a buried pipeline is exceeded the limit, breakage becomes imminent and the overall reliability of the pipe distribution network is reduced. This paper is concerned with estimating structural failure of underground flexible pipes due to corrosion induced excessive deflection, buckling, wall thrust and bending stress subject to externally applied loading. With changes of pipe wall thickness due to corrosion, the moment of inertia and the cross-sectional area of pipe wall are directly changed with time. Consequently, the chance of survival or the reliability of the pipe material is decreased over time. One numerical example has been presented for a buried steel pipe to predict the probability of failure using Hasofer-Lind and Rackwitz-Fiessler algorithm and Monte Carlo simulation. Then the parametric study and sensitivity analysis have been conducted on the reliability of pipeline with different influencing factors, e.g. pipe thickness, diameter, backfill height etc.

• Journal of The Korean Society of Agricultural Engineers
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• v.54 no.2
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• pp.37-46
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• 2012

The change of rainfall pattern and hydrologic factors due to climate change increases the occurrence probability of agricultural reservoir water shortage. Water supply assessment of reservoir is usually performed current reservoir level compared to historical water levels or the simulation of reservoir operation based on the water budget analysis. Since each reservoir has the native property for watershed, irrigation district and irrigation water requirement, it is necessary to improve the assessment methods of agricultural reservoir water capability about water resources system. This study proposed a practical methods that water supply vulnerability assessment for an agricultural reservoir based on a concept of probabilistic reliability. The vulnerability assessment of water supply is calculated from probability distribution of water demand condition and water supply condition that influences on water resources management and reservoir operations. The water supply vulnerability indices are estimated to evaluate the performance of water supply on agricultural reservoir system, and thus it is recommended a more objective method to evaluate water supply reliability.

• Journal of Korean Academy of Nursing
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• v.39 no.2
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• pp.259-269
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• 2009

Purpose: The aim of this study was to develop a breast feeding adaptation scale (BFAS) to evaluate adaptation to breastfeeding for breastfeeding mothers and their infants and to test the validity and reliability of the instrument. Methods: The study was conducted as follows: application of the conceptual framework, identification of the content domains, items generation, and test of validity and reliability. In order to test validity and reliability, two panels of experts reviewed items and subcategories of the preliminary questionnaire and then data were collected from 329 mothers who were up to 4 weeks postpartum and breastfeeding. Descriptive statistics, t-test, factor analysis, and Cronbach's alpha were used to analyze the data. Results: The conceptual framework was based on the Roy adaptation model. The content domains were developed via literature review, review of instruments, and data acquired from the interviews of breastfeeding mothers and nurses. A total of 69 items belonging to 8 domains were generated. A reduction to 44 preliminary items was accomplished through content validity analysis. Factor analysis extracted 8 factors with a total of 27 items on a 5-point Likert scale. Content validity, construct validity, criterion validity, and reliability of the BFAS were established. Conclusion: The newly developed BFAS is a reliable and valid instrument with which the adaptation of breastfeeding mothers and their infants to the breastfeeding behavior can be evaluated.

• Journal of Korean Academy of Nursing
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• v.47 no.1
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• pp.86-97
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• 2017

Purpose: The purpose of this study was to develop and test the psychometric properties of the newly developed instrument, Meaning in Life, for elderly Korean people. Methods: Ten older adults participated in the qualitative research used to develop the initial items. Participants for the psychometric testing were 371 community-dwelling older adults. Validity and reliability analyses included content, construct, and criterion-related validities, internal consistency, and test-retest reliability. Results: The Meaning in Life Scale consisted of 12 items with three distinct factors; value of life, source of life, and will to live, which explained 86.7% of the total variance. A three-factor structure was validated by confirmatory factor analysis. Criterion-related validity was supported by comparison with the Purpose in Life Test (r=.74). Reliabilities were secured with test-retest reliability of Intra-class Correlation Coefficient (ICC) .85 and the Cronbach's alpha coefficient .90. Conclusion: The results of this study indicate that this instrument is useful to measure meaning in life in Korean elders.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.19 no.1
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• pp.28-37
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• 2008

Objectives : This study was conducted in order to examine the reliability and validity of the Children's Color Trails Test (CCTT). The objective of the study was also to provide the Korean normative data for the CCTT. Methods : Normative samples consisted of 766 children and adolescents living in Seoul and aged from 5 to 15 years. Eighty children who were diagnosed with ADHD, based on the DSM-IV criterion, were recruited from Seoul National University Children's Hospital. Among them, 46 ADHD children were receiving medication, while 34 children were drug-free. Results : The scores of the CCTT were significantly correlated with those of the Stroop test. Three factors were extracted through factor analysis-visual tracking and cognitive flexibility, distractibility and susceptibility to interference, and simple attention and impulsivity. The completion time of the CCTT for all children tended to decrease as age increased. There were significant differences in the CCTT scores between the ADHD group receiving medication, the ADHD-drug free group and the normal groups. The CCTT also showed sound test-retest reliability. These results confirmed the reliability and validity of the CCTT. Finally, we provided the Korean normative data for the CCTT. Conclusion : These results suggest that the CCTT is a reliable and valid test, which can be used to assess frontal function related to child psychiatric disorders in Korean children.

• Journal of Korean Academy of Nursing
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• v.44 no.2
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• pp.209-218
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• 2014

Purpose: The purpose of this study was to develop an instrument to assess bullying of nurses, and test the validity and reliability of the instrument. Methods: The initial thirty items of WPBN-TI were identified through a review of the literature on types bullying related to nursing and in-depth interviews with 14 nurses who experienced bullying at work. Sixteen items were developed through 2 content validity tests by 9 experts and 10 nurses. The final WPBN-TI instrument was evaluated by 458 nurses from five general hospitals in the Incheon metropolitan area. SPSS 18.0 program was used to assess the instrument based on internal consistency reliability, construct validity, and criterion validity. Results: WPBN-TI consisted of 16 items with three distinct factors (verbal and nonverbal bullying, work-related bullying, and external threats), which explained 60.3% of the total variance. The convergent validity and determinant validity for WPBN-TI were 100.0%, 89.7%, respectively. Known-groups validity of WPBN-TI was proven through the mean difference between subjective perception of bullying. The satisfied criterion validity for WPBN-TI was more than .70. The reliability of WPBN-TI was Cronbach's ${\alpha}$ of .91. Conclusions: WPBN-TI with high validity and reliability is suitable to determine types of bullying in nursing workplace.