• Journal of Electrical Engineering and Technology
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• v.1 no.4
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• pp.414-422
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• 2006

Deterministic techniques have been applied in power system planning for many years and there is a growing interest in combining these techniques with probabilistic considerations to assess the increased system stress due to the restructured electricity environment. The overall reliability framework proposed in this paper incorporates the deterministic N-1 criterion in a probabilistic framework, and results in the joint inclusion of both adequacy and security considerations in system planning. The combined framework is achieved using system well-being analysis and traditional adequacy assessment. System well-being analysis is used to quantify the degree of N-1 security and N-1 insecurity in terms of probabilities and frequencies. Traditional adequacy assessment is Incorporated to quantify the magnitude of the severity and consequences associated with system failure. The concepts are illustrated by application to two test systems. The results based on the overall reliability analysis framework indicate that adequacy indices are adversely affected by a generation deficient environment and security indices are adversely affected by a transmission deficient environment. The combined adequacy and security framework presented in this paper can assist system planners to realize the overall benefits associated with system modifications based on the degree of adequacy and security, and therefore facilitate the decision making process.

• Journal of Korean Critical Care Nursing
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• v.11 no.3
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• pp.12-22
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• 2018

Purpose : This methodological study develops an oral health assessment tool for critically ill patients. Method : From February 15 to April 30, 2014, this study was conducted to test the validity and reliability of the tool at two general hospitals and three medical and surgical intensive care units (ICUs) in Seoul, Korea. Results : The result of the intraclass correlation coefficient to test the between-observer reliability by analyzing the oral health assessment scores before and after oral nursing care showed that .93 of before oral care and .90 of after oral care. The correlation coefficient values of .68 (p<.001) and .71 (p<.001) before and after providing oral nursing care, respectively, indicated the presence of a statistically significant correlation between the tool and the criterion. Using the paired t-test, the differentiated validity of the tool was tested in patients who had developed pneumonia after entering the ICU. A statistically significant difference in scores was found between the time of entering the ICU and that of developing pneumonia (t=-8.73, p<.001), which provided evidence for the differentiated validity of the tool. Conclusions : Since the validity and reliability of the tool developed in this study were verified, this tool can be used to assess the oral health conditions of critically ill patients.

• Journal of Mechanical Science and Technology
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• v.15 no.1
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• pp.44-51
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• 2001

One of the recent issues in design of the spot-welded structure such as the automobile body is to develop an economical prediction method of the fatigue design criterion without additional fatigue test. In this paper, as one of basic investigation for developing such methods, fracture mechanical approach was investigated. First, the Model I, Mode II and Mode III, stress intensity factors were analyzed. Second, strain energy density factor (S) synthetically including them was calculated. And finally, in order to decide the systematic fatigue design criterion by using this strain energy density factor, fatigue data of the ΔP-N(sub)f obtained on the various in-plane bending type spot-welded lap joints were systematically re-arranged in the ΔS-N(sub)f relation. And its utility and reliability were verified by the theory of Weibull probability distribution function. The reliability of the proposed fatigue life prediction value at 10(sup)7 cycles by the strain energy density factor was estimated by 85%. Therefore, it is possible to decide the fatigue design criterion of spot-welded lap joint instead of the ΔP-N(sub)f relation.

• Journal of Korean Academy of Nursing
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• v.50 no.1
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• pp.132-146
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• 2020

Purpose: The purpose of this study was to develop a new version of Spirituality Assessment Scale (N-SAS) and verify its reliability and validity. Methods: The total of 59 preliminary items for the N-SAS were selected through a literature review, two rounds of experts' content validation, cognitive interviews, and pre-tests. Verification of its reliability and validity was divided into two phases. In Phase I, questionnaires were collected from 219 adults. Reliability was tested using Cronbach's alpha, validity with item analysis, and exploratory factor analysis. In Phase II, questionnaires developed based on the results of Phase I were collected from 225 adults. Reliability was tested using Cronbach's alpha, validity with confirmatory factor analysis, and criterion validity. Results: The final version of the N-SAS comprised two dimensions (vertical and horizontal), four domains (relationship with God; meaning of life and self-integration; self-transcendence; and relationship with others, neighborhoods, and nature), and 44 items were identified. Total Cronbach's α was .97; those of each subscale ranged from .79 to .98. N-SAS scores were positively correlated with the scores of Howden's Spiritual Assessment Scale (r=.81, p<.001). Conclusion: Findings suggest that the N-SAS can be used to measure spirituality in adults. The use of N-SAS is expected to facilitate perceiving patient's spiritual needs and providing spiritual care.

• Journal of Korean Academy of Nursing
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• v.45 no.3
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• pp.412-419
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• 2015

Purpose: The aim of this study was to evaluate the validity and reliability of the Korean version of the Person-centered Care Assessment Tool (P-CAT). Methods: The English P-CAT was translated into Korean with forward and backward translation. Survey data were collected from 458 staff in 17 long-term care facilities in Korea. Construct validity and criterion related validity were evaluated. Cronbach's alpha was used to assess reliability. Results: The Korean version of P-CAT was shown to be valid homogeneously by factor, item and content analysis. Internal consistency reliability was satisfactory in which the values of factor 1, factor 2 and the total scale were .84, .77 and .86 respectively. Exploratory factor analysis supported the construct validity with a two-factor solution. Factor loadings of the 13 items ranged in .34~.80. Criterion validity to the Person-centered Climate Questionnaire-staff (PCQ-S) was .74 (p<.001). Conclusion: The Korean version of the P-CAT was found to be an applicable instrument with satisfactory reliability and validity for further use in measuring successful person-centered care in long-term care facilities for older persons.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2001.04a
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• pp.102-109
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• 2001

In order to take account of the statistical properties of probability variables used in the structural analysis, the conventional approach using the safety factor based on past experience usually estimated the safety of a structure. The real structures could only be analyzed with the error in estimation of loads, material characters and the dimensions of the members. But the errors should be considered systematically in the structural analysis. Structural safety could not precisely be appraised by the traditional structural design concept. Recently, new approach based on the probability concept has been applied to the assessment of structural safety using the reliability concept. Thus, the computer program by the Probabilistic FEM is developed by incorporating the probabilistic concept into the conventional FEM method. This paper estimated for the reliability of a plane stress structure by Advanced First-Order Second Moment method using von Mises, Tresca and Mohr-Coulomb failure criterions. The reliability index and failure probability of attained by the Monte Carlo Simulation method with the von Mises criterion were same as PFEM, but the Monte Carlo Simulation were very time-consuming. The variance of member thickness and load could influence the reliability and failure probability most sensitively among the design variables from the results of the parameter analysis. And proper failure criterion must be used to design safely.

• Journal of Korean Academy of Nursing
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• v.50 no.6
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• pp.848-862
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• 2020

Purpose: The purpose of this study was to develop an instrument to evaluate the needs satisfaction of nurses and examine its validity and reliability. Methods: The initial items for the instrument were developed through a literature review and interviews, using the conceptual framework of Maslow's hierarchy of needs theory. The initial items were evaluated for content validity by 14 experts. Four hundred and eighty-six clinical nurses participated in this study through offline and online surveys to test the reliability and validity of the instrument. The first evaluation (n = 256) was used for item analysis and exploratory factor analysis, and the second evaluation (n = 230) was used to conduct a confirmatory factor analysis and to assess the criterion-related validity and internal consistency of the instrument. Test-retest reliability was analyzed using data from 30 nurses. Results: The final instrument consisted of 30 items with two sub-factors for five needs that were identified through the confirmatory factor analysis. The criterion-related validity was established using the five need satisfaction measures (r = .56). Cronbach's α for total items was .90, and test-retest reliability was .89. Conclusion: The findings from this study indicate that this instrument has sufficient validity and reliability. This instrument can be used for the development of nursing interventions to improve the needs satisfaction of clinical nurses.

• Journal of muscle and joint health
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• v.5 no.2
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• pp.206-221
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• 1998

The purpose of this study was to validate translated Multidimensional Assessment of Fatigue(MAF) scale. The scale is a 16-item scale that measures four dimensions of fatigue : severity, distress, impact, timing. Fourteen items are numerical rating scales and 2 items have multiple choice responses. Data were collected from the 137 patients with rheumatoid arthritis after content validation. Criterion validity was tested by correlation coefficient with Piper Fatigue Scale, which resulted in 0.7573(p<.0000). Construct validity was tested by item analysis and factor analysis. Corrected item-total correlation coefficients were 0.63-0.88. And factor analysis showed 2 factors : fatigue degree factor and fatigue impact factor. These two factors explained 73.5% of total variance. Reliability of internal consistency was 0.96 in Cronbach's alpha. Further validation study is necessary in each factor in other settings with other subjects.

• Korean Journal of Child Studies
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• v.24 no.3
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• pp.135-149
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• 2003

This study aimed to develop an observation scale for assessing the quality of day care programs and to examine reliability and validity of the scale. Instruments included 3 self-assessment scales, the Evaluation Scale for Early Childhood Programs and an observation scale completed by 8 trained observers in 89 day care sites. Item analysis indicated that most items were acceptable in terms of item discrimination and item response distribution. Cronbach ${\alpha}^{\prime}s$ and inter-observer reliability were relatively high. Validity of the scale was evidenced by correlations between the observation scale and the criterion measure and inter-correlations among sub-areas of the observation scale. Scores on the observation scale were validated by quality ratings from self-assessment scores.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1996.04a
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• pp.202-211
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• 1996

A number of typical type of steel-box pedestrian bridges are constructed in the metropolitan highway or heavy traffic urban area. Although it has the advantage of speedy construction because of its simple structural form and prefabricated erection method, it has been reported that many of these bridges are deteriorated or damaged and thus are in the state such that it would give unsafe and uncomfortable feeling to pedestrians. In the paper, for the realistic assessment of safety and residual earring-capacity of deteriorated and/or damaged steel box pedestrian bridges, an interactive non-linear limit state model are formulated based on the von Mises' combined stress yield criterion. It is demonstrated that the proposal model is effective for the reliability-based safety assessment and residual carrying-capacity evaluation of steel-box pedestrian bridges. In addition, this study suggests an effective and practical field load test method for pedestrian bridges.