• Title/Summary/Keyword: reliability assessment criterion

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Assessment of Hot Deformation and Grain Size Distribution in a Udimet 720Li Pancake (Udimet 720Li 합금의 고온변형 및 결정립분포 예측)

  • 염종택;나영상;박노광
    • Transactions of Materials Processing
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    • v.11 no.6
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    • pp.538-546
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    • 2002
  • Hot deformation behavior of Udiment720Li was characterized by compression tests in the temperature range of 10$25^{\circ}C$ to 115$0^{\circ}C$ and the strain rate range of $0.0005 s^{-1};to;5 s^{-1}$. The combination of dynamic material model (DMM) and Ziegler's instability criterion was applied to predict an optimum condition and unstable regions for hot forming. A dynamic recrystallization model coupled with FEM results was used to interpret the evolution of microstructures. In order to verify the reliability of the present coupled model, isothermal forging was performed in the temperature range 1050~115$0^{\circ}C$ at strain rates of $0.05 s^{-1};and;0.005 s^{-1}$. The present model was successfully applied to the hot forming process of Udimet720Li.

Analysis of Problems of Water Supply Capacity Determination in Water Resources Systems (수자원시스템의 용수공급량 결정방법의 문제점 분석)

  • Lee, Gwang-Man;Yi, Jaeeung
    • Journal of Korea Water Resources Association
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    • v.47 no.4
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    • pp.331-342
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    • 2014
  • In water resources planning, to decide proper water supply capacity is a very important task. Once water supply system such as a dam is decided, it will affect whole range of water resources circumstances for a long time. Even though systematic approaches have been implemented since 1980, many problems are still prevail in reality. Especially some issues related to the reliability analysis method used in planning dams in Korea have been persistently brought up. This study is to diagnose problems on the reliability criterion in water supply capacity assessment of water resources systems and discuss a valid method. As a result, the estimates by the different analysis time intervals, in case of the temporal reliability, show no large difference, but there is a large difference when assessment time intervals are differently applied. The volumetric reliability accounts for 2~3% higher than that of the temporal reliability, and resiliency and vulnerability also show large differences by the analysis time intervals.

ReliabIlity analysis of containment building subjected to earthquake load using response surface method

  • Lee, Seong Lo
    • Computers and Concrete
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    • v.3 no.1
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    • pp.1-15
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    • 2006
  • The seismic safety of reinforced concrete containment building can be evaluated by probabilistic analysis considering randomness of earthquake, which is more rational than deterministic analysis. In the safety assessment of earthquake-resistant structures by the deterministic theory, it is not easy to consider the effects of random variables but the reliability theory and random vibration theory are useful to assess the seismic safety with considering random effects. The reliability assessment of reinforced concrete containment building subjected to earthquake load includes the structural analysis considering random variables such as load, resistance and analysis method, the definition of limit states and the reliability analysis. The reliability analysis procedure requires much time and labor and also needs to get the high confidence in results. In this study, random vibration analysis of containment building is performed with random variables as earthquake load, concrete compressive strength, modal damping ratio. The seismic responses of critical elements of structure are approximated at the most probable failure point by the response surface method. The response surface method helps to figure out the quantitative characteristics of structural response variability. And the limit state is defined as the failure surface of concrete under multi-axial stress, finally the limit state probability of failure can be obtained simply by first-order second moment method. The reliability analysis for the multiaxial strength limit state and the uniaxial strength limit state is performed and the results are compared with each other. This study concludes that the multiaxial failure criterion is a likely limit state to predict concrete failure strength under combined state of stresses and the reliability analysis results are compatible with the fact that the maximum compressive strength of concrete under biaxial compression state increases.

Psychometric Evaluation of the Korean Social Support Questionnaire (한국 사회적지지 측정도구 개발)

  • Oh, Ka-Sil;Oh, Kyong-Ok;Lee, Sook-Ja;Kim, Jeong-Ah;Jeong, Chu-Ja;Kim, Hye-Ryoung;Jun, Hoa-Yun;Kang, Jung-Hee
    • Journal of Korean Academy of Nursing
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    • v.38 no.6
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    • pp.881-890
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    • 2008
  • Purpose: Research related to social support in Korea has been hampered by paucity of measurement tools reflecting Korean culture. The aim of the study was to develop Korean social support questionnaire (KSSQ) based on the Korean social support pyramid and to test psychometric properties of the KSSQ. Methods: The questionnaire was administered to 701 subjects and 658 college students. Psychometric analyses included factor analyses, expert validity, criterion-related validity, internal consistency, and test-retest reliability. Results: A principal components analysis support for construct validity, eliciting a three factor solution accounting for 65.46% of variance in scores. Concurrent and discriminant validity supported criterion-related validity. Internal consistency of reliability was support with Cronbach's alpha of .97-.98 for the entire scale. Test-retest reliability was .76. Conclusion: This initial testing of KSSQ to measure Korean social support demonstrates evidence of reliability and validity. Assessment of known-group validity and norm establishment of KSSQ are suggested to provide further sound psychometric properties and practical measurement tools.

Reliability and Validity of Korean Version Northwick Park Neck Pain Questionnaire in Neck Pain Patients (경통 환자들을 위한 한국어판 Northwick Park Neck Pain Questionnaire의 신뢰도와 타당도)

  • Lee, Kwan-Woo;Seo, Hyun-Do;Jung, Kyoung-Sim;Kim, Sang-Hwun;Chung, Yi-Jung
    • Physical Therapy Korea
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    • v.17 no.3
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    • pp.68-76
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    • 2010
  • The purpose of this study was to establish reliability and validity of the Northwick Park Neck Pain Questionnaire (NPQ) translated into Korean for neck pain patients. Sixty-two subjects (35 males, 27 females) with neck pain enrolled in the study. They completed a standardized self-administered questionnaire that included pain intensity, sleeping, sensory at night, duration of symptoms, carrying, reading and watching television, working, social activities, and driving. Reliability was determined by intraclass correlation coefficient (ICC) and Cronbach's alpha by internal consistency. Validity was examined by correlating the NPQ scores to the Visual Analog Scale (VAS) score. Test-retest reliability of the translated versions of the NPQ was good ICC(2,1)=.83 (95%CI=.85~.95). Cronbach's alpha value for NPQ was found to be .87 and this was statistically significant (p<.05). The criterion-related validity coefficients was .75 (p<.01). We concluded that the Korean version NPQ was shown to be a reliable and valid instrument for the assessment of neck pain.

Reliability and Validity of the Neck Disability Index in Neck Pain Patients (경통 환자 평가를 위한 Neck Disability Index의 신뢰도와 타당도)

  • Lee, Eun-Woo;Shin, Won-Seob;Jung, Kyoung-Sim;Chung, Yi-Jung
    • Physical Therapy Korea
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    • v.14 no.3
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    • pp.97-106
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    • 2007
  • The purpose of this study was to determine reliability and validity of the Neck Disability Index (NDI) now in use for the first time in neck pain patients of Korea. Fifty subjects (26 males and24 female) with neck pain enrolled in the study. They completed a standardized self-administered questionnaire that include pain intensity, personal care, lifting, reading, headaches, concentration, work, driving, sleeping and recreation. Reliability was determined by intra-class correlation coefficient (ICC) and Cronbach's alpha by internal consistency. Validity was examined by correlating the NDI scores to the Visual Analog Scale (VAS) score. The Test-retest reliability of the translated versions of the NDI was good ICC (2,1) = .90 (95%CI .85 .95). Cronbach's alpha value for NDI was found to be .95 and this was statistically significant (p<.05). The criterion-related validity coefficients was .72 (p<.01). We conclude that the Korean version of NDI has shown to be a reliable and valid instrument for the assessment of neck pain.

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Review on Reliability and Validity of Questionnaire of Pattern Identification in Traditional Chinese Medicine -Using China National Knowledge Infrastructure- (중의 변증 설문도구의 신뢰도 및 타당도 고찰 -China National Knowledge Infrastructure를 이용하여-)

  • Yeo, Min Kyung;Dong, Sang Oak;Lee, Young Seop;Jang, Eun Su
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.29 no.3
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    • pp.246-255
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    • 2015
  • The purpose of this study is to investigate the reliability and validity of the questionnaire of pattern identification (PI) in traditional chinese medicine (TCM), through the systematic review of china national knowledge infrastructure (CNKI) database. We searched the articles related with reliability and validity of the questionnaire of PI and published from January 1994 to December 2013. Seventeen questionnaires were analyzed in this study. The twelve (70.6%) questionnaires were developed on the base of specific disease, and five (29.4%) ones were developed on the base of non-specific disease. Three of PI questionnaires showed low inter-item consistency reliability. Exploratory factor analysis of construct validity, content validity, and criterion validity analysis were commonly used on the assessment of validity, but none of them was analysed at the same study. There was only one questionnaire of the ischemic stroke that examined the sensitivity and specificity of both training and test groups in spite of the absence of a gold standard.

Psychometric Properties of the Korean Version of the Caregiver Reaction Assessment(K-CRA) (한국형 부양자반응척도(Caregiver Reaction Assessment)의 구성타당화 연구)

  • Lee, Minhong
    • 한국노년학
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    • v.29 no.2
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    • pp.407-424
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    • 2009
  • This study aims to evaluate psychometric properties of the korean version of the caregiver reaction assessment. A total of 253 family caregivers for older adults with physical or mental impairments are recruited using the purposive sampling method. The psychometric properties of the instrument are tested by item-analysis, exploratory factor analysis(EFA), and convergent and criterion-related validity. The results show that the internal consistency values for the five dimensions of the K-CRA are good. The convergent and criterion-related validity is empirically confirmed. The EFA with the principal component method reveals the factor structure in the observed variables. The findings of the study confirmed that the K-CRA was both reliable and valid. In conclusion, the K-CRA would be useful in clinical and research settings in South Korea.

Development of a Triage Competency Scale for Emergency Nurses (응급실 간호사의 중증도 분류 역량 측정도구 개발)

  • Moon, Sun Hee;Park, Yeon Hwan
    • Journal of Korean Academy of Nursing
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    • v.48 no.3
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    • pp.362-374
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    • 2018
  • Purpose: This study aimed to develop a triage competency scale (TCS) for emergency nurses, and to evaluate its validity and reliability. Methods: Preliminary items were derived based on the attributes and indicators elicited from a concept analysis study on triage competency. Ten experts assessed whether the preliminary items belonged to the construct factor and determined the appropriateness of each item. A revised questionnaire was administered to 250 nurses in 18 emergency departments to evaluate the reliability and validity of the scale. Data analysis comprised item analysis, confirmatory factor analysis, contrasted group validity, and criterion-related validity, including criterion-related validity of the problem solving method using video scenarios. Results: The item analysis and confirmatory factor analysis yielded 5 factors with 30 items; the fit index of the derived model was good (${\chi}^2/df=2.46$, Root Mean squared Residual=.04, Root Mean Squared Error of Approximation=.08). Additionally, contrasted group validity was assessed. Participants were classified as novice, advanced beginner, competent, and proficient, and significant differences were observed in the mean score for each group (F=6.02, p=.001). With reference to criterion-related validity, there was a positive correlation between scores on the TCS and the Clinical Decision Making in Nursing Scale (r=.48, p<.001). Further, the total score on the problem solving method using video scenarios was positively correlated with the TCS score (r=.13, p=.04). The Cronbach's ${\alpha}$ of the final model was .91. Conclusion: Our TCS is useful for the objective assessment of triage competency among emergency nurses and the evaluation of triage education programs.

Development of a Health Literacy Assessment Scale for Asian Immigrant Women in South Korea (결혼이주여성의 건강문해력 측정도구 개발)

  • An, Jisook;Yang, Sook Ja
    • Research in Community and Public Health Nursing
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    • v.26 no.4
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    • pp.330-341
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    • 2015
  • Purpose: This study developed a self-report measure for easy assessing of the health literacy of Asian immigrant women in South Korea. Methods: After a literature review, focus group interviews, and content validity evaluation, 14 preliminary items were generated. These were translated into Chinese, Vietnamese, and English. Data were collected from 229 Asian immigrant women. Validity and reliability tests were conducted. Results: Factor analysis yielded final 10 items in three factors: primary functional and interactive health literacy, secondary functional and interactive health literacy, and critical health literacy, which explained 61.90% of the total variance of health literacy. In known-group comparisons, health literacy was significantly lower in recent immigrants, those with a low education level, and those with low Korean language proficiency. For convergent validity, health literacy was positively associated with health specific self-efficacy and maternal health knowledge. For criterion-related validity, health literacy was positively associated with the REALM-SF. The overall reliability coefficient (Cronbach's ${\alpha}$) of the instrument was .773. Conclusion: The Health Literacy Assessment Scale for Asian Immigrant Women (HLAS) represents a multidimensional construct which encompasses functional, interactive, and critical health literacy. This self-report HLAS can be a useful and convenient method for appraising the health literacy of Asian immigrant women.