• Title/Summary/Keyword: Coefficient of reliability

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Thermo-Mechanical Reliability of TSV based 3D-IC (TSV 기반 3차원 소자의 열적-기계적 신뢰성)

  • Yoon, Taeshik;Kim, Taek-Soo
    • Journal of the Microelectronics and Packaging Society
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    • v.24 no.1
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    • pp.35-43
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    • 2017
  • The three-dimensional integrated circuit (3D-IC) is a general trend for the miniaturized and high-performance electronic devices. The through-silicon-via (TSV) is the advanced interconnection method to achieve 3D integration, which uses vertical metal via through silicon substrate. However, the TSV based 3D-IC undergoes severe thermo-mechanical stress due to the CTE (coefficient of thermal expansion) mismatch between via and silicon. The thermo-mechanical stress induces mechanical failure on silicon and silicon-via interface, which reduces the device reliability. In this paper, the thermo-mechanical reliability of TSV based 3D-IC is reviewed in terms of mechanical fracture, heat conduction, and material characteristic. Furthermore, the state of the art via-level and package-level design techniques are introduced to improve the reliability of TSV based 3D-IC.

A reliability analysis of syndrome differentiation questionnaire for obesity (비만변증 설문지에 대한 신뢰도 분석)

  • Kang, Byeong-Kab;Moon, Jin-Seok;Choi, Sun-Mi
    • Korean Journal of Oriental Medicine
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    • v.13 no.1 s.19
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    • pp.109-114
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    • 2007
  • The high position condition 10 escape which the obesity person appeals. Obesity Pattern-Identification question it will yell and 243 subjects which to the obesity in the patient of 517 subjects which draw up correspond. (longitude obesity 153 person, altitude obesity 90 person) against it analyzes. In order to analyze the reliability of the items which diagnose each Pattern-Identification it used Cronbach alpha coefficient and escape it did the alpha of each item. Alpha value of each Pattern-Identification than appears more highly the item which it will be able to consider an elimination in the item which decreases a reliability. In that phlegm-retention syndrome is bigger alpha coefficient 0.784 than 'meal quantity is few'(0.787) a possibility of seeing in the item which decreases a reliability to the place where it diagnoses it puts in phlegm-retention syndrome.

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A Comparative Study of Software Reliability Model Considering Log Type Mean Value Function (로그형 평균값함수를 고려한 소프트웨어 신뢰성모형에 대한 비교연구)

  • Shin, Hyun Cheul;Kim, Hee Cheul
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.10 no.4
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    • pp.19-27
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    • 2014
  • Software reliability in the software development process is an important issue. Software process improvement helps in finishing with reliable software product. Infinite failure NHPP software reliability models presented in the literature exhibit either constant, monotonic increasing or monotonic decreasing failure occurrence rates per fault. In this paper, proposes the reliability model with log type mean value function (Musa-Okumoto and log power model), which made out efficiency application for software reliability. Algorithm to estimate the parameters used to maximum likelihood estimator and bisection method, model selection based on mean square error (MSE) and coefficient of determination($R^2$), for the sake of efficient model, was employed. Analysis of failure using real data set for the sake of proposing log type mean value function was employed. This analysis of failure data compared with log type mean value function. In order to insurance for the reliability of data, Laplace trend test was employed. In this study, the log type model is also efficient in terms of reliability because it (the coefficient of determination is 70% or more) in the field of the conventional model can be used as an alternative could be confirmed. From this paper, software developers have to consider the growth model by prior knowledge of the software to identify failure modes which can be able to help.

The Development of Maternal Conflict Scale- for mothers whose over toddler ~below preschool child - (모성갈등 도구개발 - 유아기에서 학령전기 자녀가 있는 어머니를 대상으로 -)

  • Lee Seon-Ah
    • Child Health Nursing Research
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    • v.8 no.3
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    • pp.291-301
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    • 2002
  • This study was performed to develop a scale of maternal conflict based on already established scales and the literature review. The major purpose of this study was to develop a scale of which contains difficulties which mother can feel to rearing her child and can be applied to mothers at home or employed mothers. 68 items were developed. For content validity test, the items were examined by 7 experts panel with Likert 4 scale. The 39 items were selected as high validity from 86% of the experts. The item number of each area and the misunderstanding words were corrected by advices of experts. 10 mothers again examined 39 items in order to correct the misunderstanding words and the long sentences. For reliability and factor analysis of 39 items, 496 mothers participated. 34 items were chosen because 5 items that corrected item-total correlation coefficient were lower than 0.2 were excluded by the result of reliability analysis. Factor analysis was done with 34items. 6 factors were classified higher than eigen value 1.0, 28 items were chosen because 6 items that factor loadings were lower than 0.4 were excluded. These factors were named as employment and caring for child(6 items), child education(5 items), support system for caring for child(4 items), interaction with mother and child(4 items), view of maternal role(5 items) and me as human being(4 items). Reliability analysis was done with 28 items. 1 item(36 number of factor 1) was excluded because corrected item-total correlation coefficient were lower than 0.2. Therefore, 27 items were chosen. Maternal Conflict Scale was contained 27 items. The corrected item-total correlation coefficient of 27 items were ranged from .2345 to .5240 and Cronbach alpha coefficient of those was .8207 by the results of reliability analysis. It can be evaluated that this scale had a high validity and reliability because of passing through an objective process of test.

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A Reliability Study of the Test of Playfulness in Attention Deficit Hyperactivity Disorder (ADHD) (주의력결핍 과잉행동장애 아동의 Test of Playfulness 신뢰도 연구)

  • Lee, Na-hael;Kim, Kyeong-Mi
    • The Journal of Korean Academy of Sensory Integration
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    • v.14 no.1
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    • pp.1-8
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    • 2016
  • Objective : The purpose of this study was to determine the reliability of Test of Playfulness (ToP) in Attention Deficit Hyperactivity Disorder (ADHD) children. Methods : Twenty ADHD children participated in this study. To determine inter-rater reliability, two raters was evaluated by Test of Playfulness scores and analyzed Kappa coefficient and total agreement and intraclass correlation coefficient (ICC). Results : Total agreement was the range of 75%~95% and the Kappa coefficients was the range of. 45~1.00. Analyzing inter-rater reliability by ICC showed very high reliability: Intrinsic motivation was .96, internal control was .98, suspension of reality was .90, framing was .98, total score was .99. Conclusion : A reliability of Test of Playflness of children with ADHD showed that high. On the basis of this study, it will provide availability for clinical evaluation of children with ADHD, and basic study on the play of children with ADHD.

The Reliability and Validity of Hip Range of Motion Measurement using a Smart phone Operative Patient (엉덩관절 수술 환자에서 스마트폰을 이용한 관절가동범위 측정의 신뢰도 및 타당도 연구)

  • Park, Sun-Wook;Kim, Myoung-Soo;Bae, Hyo-Sun;Cha, Yong-Ho
    • Journal of the Korean Society of Physical Medicine
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    • v.10 no.2
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    • pp.1-7
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    • 2015
  • PURPOSE: The aims of this study were to assess the intra-tester and inter-tester reliability and validity of hip range of motion using a smart phone in hip operative patients. METHODS: Twenty-five patients (eight total hip arthroplasty and seventeen femur neck fracture) participated in this study. The range of motions in active and passive hip flexion, abduction and external rotation were measured with a goniometer and smart phone over two times by two observers. The intra-tester and inter-tester reliability were evaluated using the intraclass correlation coefficient (ICC2,1). The validity was measured by Pearson's correlation coefficient RESULTS: The intra-observer reliability was good in all measured items (ICC>0.78). The inter-observer reliability was high with ICC (>0.90). All correlation coefficients of smart phone and goniometer was greater than 0.85 and showed a significant positive correlation (p<0.01). CONCLUSION: The range of motion measurement with a smart phone showed acceptable reliability. Therefore, it could be convenient and have economical benefits to measure the range of motion of the hip joint using a smart phone.

The Reliability and Validity of Korean Version of Wong and Law Emotional Intelligence Scale (K-WLEIS) (한국어판 감성지능 측정도구의 신뢰도와 타당도 검증)

  • Jeong, Harim;Choi, Heejung;Park, Myungsook
    • Journal of Korean Academy of Nursing
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    • v.50 no.4
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    • pp.611-620
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    • 2020
  • Purpose: The aim of this study was to evaluate the reliability and validity of the Korean version of the Wong and Law Emotional Intelligence Scale (K-WLEIS). Methods: Data were collected from 360 nursing students using a self reported questionnaire. Exploratory and confirmatory factor analysis were used to test construct validity. Convergence validity was identified by correlation with communication competency. Item convergent and discriminant validity were also analyzed. Reliability was evaluated internal consistency and test-retest reliability. Results: The results of exploratory factor analysis showed that the eigen values ranged from 1.34 to 5.86 and 73.2% of the total explained variance. Confirmatory factor analysis showed adequate model fit indices (χ2/df 1.89, RMSEA .07, GFI .89, CFI .95, and TLI .93) and standardized factor loadings (.48 to .87). The average extracted variances (.71 to .79) and composite reliability (.80 to .87) validated convergence and discriminant validity of the items. Test-retest reliability of intra-class correlation coefficient was .90 and the Cronbach's alpha coefficient was .88. Conclusion: The K-WLEIS is an appropriate scale for measuring the emotional intelligence of Korean nursing students. Therefore, it is expected that the K-WLEIS will be used for nursing education programs to improve nursing students' emotional intelligence.

Outlier Impact on the Power of Significance Test for Cronbach Alpha Reliability Coefficient

  • Yonghwan Um
    • Journal of the Korea Society of Computer and Information
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    • v.28 no.5
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    • pp.179-187
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    • 2023
  • In this paper, we studied the impact of outliers on the power of the significance tests for Cronbach alpha reliability coefficient. Four variables were varied: sample size, the number of items, the number of outliers and population Cronbach Alpha levels. We simulated data using multivariate normal distribution and used outliers sampled from uniform distribution. To test the significance of Cronbach Alpha Reliability, parametric approach(F statistic) and permutation method were used. Consequently, we observed that the powers of permutation test are equal to or greater than those of F test under all conditions, and also both F test and permutation test lose the power as the number of outliers increases, and that these effects of outliers on the power are enhanced for increasing population alpha levels.

Fast Dynamic Reliability Estimation Approach of Seismically Excited SDOF Structure (지진하중을 받는 단자유도 구조물의 신속한 동적 신뢰성 추정 방법)

  • Lee, Do-Geun;Ok, Seung-Yong
    • Journal of the Korean Society of Safety
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    • v.35 no.5
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    • pp.39-48
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    • 2020
  • This study proposes a fast estimation method of dynamic reliability indices or failure probability for SDOF structure subjected to earthquake excitations. The proposed estimation method attempts to derive coefficient function for correcting dynamic effects from static reliability analysis in order to estimate the dynamic reliability analysis results. For this purpose, a total of 60 cases of structures with various characteristics of natural frequency and damping ratio under various allowable limits were taken into account, and various types of approximation coefficient functions were considered as potential candidate models for dynamic effect correction. Each reliability index was computed by directly performing static and dynamic reliability analyses for the given 60 cases, and nonlinear curve fittings for potential candidate models were performed from the computed reliability index data. Then, the optimal estimation model was determined by evaluating the accuracy of the dynamic reliability analysis results estimated from each candidate model. Additional static and dynamic reliability analyses were performed for new models with different characteristics of natural frequency, damping ratio and allowable limit. From these results, the accuracy and numerical efficiency of the optimal estimation model were compared with the dynamic reliability analysis results. As a result, it was confirmed that the proposed model can be a very efficient tool of the dynamic reliability estimation for seismically excited SDOF structure since it can provide very fast and accurate reliability analysis results.

Reliability-Based Design of Vertical Drain Method Considering Uncertainties in Geotechnical Property (연약지반의 불확실성을 고려한 연직배수공법의 신뢰성 설계)

  • Kim, Byung-Il;Sah, Sang-Ho;Kim, Bang-Sig;Kim, Soo-Sam
    • Proceedings of the Korean Geotechical Society Conference
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    • 2006.03a
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    • pp.1148-1154
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    • 2006
  • Composite discharge capacity tests and smear effect tests are carried out to estimate the parameters for the reliability-based design of vertical drain method. Also the probabilistic and deterministic solutions of radial consolidation theory are presented. It compared to the result of reliability-based design and that of deterministic design using the tested and estimated parameters. The results indicated that the drain spacing is larger the deterministic method than the probabilistic method because the former is not considered the uncertainties in the properties of soil. The divergence of methods is dependent on the probability of achieving target degree of consolidation by a given time and the coefficient of variation(COV) of the coefficient of horizontal consolidation$(c_h)$.

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