• Journal of the Korean Society of Safety
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• v.12 no.4
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• pp.180-190
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• 1997

A new method in the fault tree analysis (FTA) for the reliability calculation is suggested. Two steps are necessary in traditional method in evaluation of the occurrence probability of top event in fault tree (FT). The first step is to find the minimal outsets, and the second one is to substitute the result into the poincare equation. In order to reduce the enormous computing time of this method, lots of rapid algorithms have been developed. Almost of all achievements were, however, based on the partial structural properties of FT. In this paper, the FT is transformed to a non-linear graph G which has the same minimal outsets of original n, and then the reliability is calculated using the domination theory. In this new method, the required number of equation terms are at most $2^n$ (n is node number of graph G), while $2^m$-1 (m is the number of minimal cutsets) calculation terms are required in the poincare equation in traditional method. Since m>>n in general. our new method reduces the calculation time significantly.

• Proceedings of the KIEE Conference
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• 2002.11b
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• pp.361-364
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• 2002

The paper presents a basic study on reliability evaluation using METRIS for long term expansion planning of transmission system. The main frame of methodelogy of the reliability evaluation of a transmission system in the METRIS is based on evaluation philosophy that the reliability level of a transmission system is equal to difference between the reliability level of HLII and that of HLI. While basic general theory of probabilistic reliability evaluation of transmission system has been presented, the GUI characteristics of input/out data system of METRIS have been demonstrated by the RBTS case study on METRIS.

• Journal of Korean Academy of Nursing
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• v.49 no.1
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• pp.80-91
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• 2019

Purpose: This study attempted to develop a scale that measures the level of patients' recognition of the nurses' care, based on Watson's caring theory, and confirmed its reliability and validity. Methods: The items were developed through a literature review and an expert content validity test. The questionnaires were administered to 285 inpatients of internal medicine and surgical units at two general hospitals. Construct validity was tested using exploratory and confirmatory factor analysis, and reliability was tested using Cronbach's alpha. Results: This process resulted in a preliminary scale composed of 34 items; We used item analysis and five exploratory factor analyses, and consequently selected 14 items composed of three factors (respect, genuineness, and relationality). The confirmatory factor analysis verified the model fit and convergent and discriminant validity of the final items; criterion validity was confirmed with the positive correlation with the measurement scale of the patient-perceived quality of nursing. The overall scale reliability had a Cronbach's alpha of .92, which indicated internal consistency and reliability. Conclusion: The developed scale showed content, construct, and criterion validity, and reliability, as well as convergent validity for each item and discriminant validity between the factors. This makes it suitable for use in a diverse range of future studies on nurse communication using structural equation models.

• Water for future
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• v.21 no.4
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• pp.407-414
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• 1988

The purpose of this paper is to study the following ; (1) how the stability and sensitivity of a given stream water quality model can be analyzed theoretically by means of the stability theory and the sensitivity theory, and (2) point out that the results of this study prove that numerical analysis for the given stream water quality model is reliable, and the model is sensitive for the variations of parameters. A stability theory which is described by the infinite Fourier series is used to analyze the numerical scheme of the model. The numerical shheme is used a backward implicit scheme. a sensitivity theory which is described by the first order linear vector equation is used to analyze theoretically the effect of variations of water quality parameters such as BOD loads, flow rate, temperature. The results of sensitivity theory are of general applicability and are presented in a analytical form. The results of this study seems to be satisfactory for the reliability of stream water quality model with respect to the numerical scheme and the variations of the water quality parameters.

• Korean Journal of Organic Agriculture
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• v.28 no.2
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• pp.119-138
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• 2020

The purpose of this study was to examine the intention of consumer acceptance of technology in agricultural production by applying the unified theory of acceptance and use of technology (UTAUT) to smart farm. In particular, this study analyzed the intention to accept the technology of agricultural students, farmers, start-up farmers, returning farmers, and returnees in the general manufacturing industry and high-tech industries, and in agricultural sectors corresponding to primary industries. The results showed that performance expectancy, social influence, facilitating conditions, IT development level, and reliability had a significant influence on the intention to use smart farm technology. However, effort expectancy and price value were rejected because no significant impact on use intention was tested. In addition, the influences of the variables showing their influence were reliability (β=.569) > IT development level (β=.252) > social influence (β=.235) > performance expectancy (β=.182) > facilitating conditions (β=.134).

• The Korean Journal of Health Service Management
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• v.11 no.2
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• pp.117-127
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• 2017

Objectives : This study aimed to identify factors of adolescents' cell-phone dependency using Agnew's General Strain Theory (GST) and the perspective of adolescents' micro-systems. A second aim was to verify the moderating effect of self-esteem. Methods : In total, 2,046 students who participated in a study on KCTPS mid. 1 panel 3 Wave by the National Youth Policy Institute were examined in this research. Data were analyzed through descriptive statistics, factor analysis, reliability tests, and hierarchical linear regression using SPSS Ver. 22.0. Results : The strain factors had a positive effect on adolescents' depression, and depression had a positive effect on cell-phone dependency. In addition, self-esteem had a negative moderating effect between depression and cell-phone dependency. Conclusions : Factors of cell-phone dependency were identified. The findings of the study indicate that an intervention is required to lower strain and depression and to enhance self-esteem among adolescents.

• Journal of the Korean Society of School Health
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• v.29 no.2
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• pp.63-70
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• 2016

Purpose: The purpose of this study was to find the factors influencing adolescents' adult media engagement. The study is based on Agnew's General Strain Theory (GST) and a micro-systemic perspective. Methods: The study examined 479 middle school freshmen who participated in the fourth wave of the Korean Children & Youth Panel Survey (KCYPS) conducted by National Youth Policy Institute. Data were analyzed through descriptive statistics, factor analysis, and reliability analysis using SPSS 22.0 Ver. Also, hypothesis testing was performed via covariance-based structure equation modeling (CB-SEM) using Amos 21.0 Ver. Results: Strain factors had positive effects on adolescent depression, and depression had a positive effect on adult media engagement. Also, cell-phone dependency had a positive mediation effect between depression and adult media engagement. Conclusion: The study's result identified the factors affecting adult media engagement. Therefore, we suggest intervention programs considering adolescents' strains, depression and cell-phone dependency to improve their health.

• Nuclear Engineering and Technology
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• v.27 no.5
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• pp.760-766
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• 1995

A general method is proposed for elastic stiffness analysis of the leaf type holddown springs using only the geometric data and Young's modulus of the springs. In this method, an engineering beam theory and Castigliano's theory are applied to elastic stiff analysis of the leaf type holddown springs. To show reliability and effectiveness of this method, the elastic stiffness from the proposed method is compared with test result and from the comparison, the unposed method has been proven to be effective for estimating the elastic stiffness of the leaf springs.

• The Journal of Industrial Distribution & Business
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• v.6 no.2
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• pp.25-30
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• 2015

Purpose - Could blood type provide the key to wellness and affect our personality? The theory that blood type is linked to personality (and other mental and physical qualities) is popular mostly in Japan, although it has carried over to Taiwan and South Korea. Research Design, Data, and Methodology - Questionnaires were distributed to 380 production line company employees. The reliability and validity of the questionnaires were examined through independence testing and the average ratio comparison of the two populations. Additionally, using Pearson's chi-square formula, the relationship between the blood group (independent variable) and general group participation (dependent variable) was tested along with the Schuprow coefficient. Result - The prioritization of blood groups over the general group participation was identified and the following results were obtained: Individual group participation is affected by personality features derived from temperament, mood, and other characteristics. Conclusion - The study showed that individual blood groups have an effect on their group cooperation, and among blood groups, blood group A had the greatest tendency to group participation, followed by blood groups O, AB, B, respectively.

• Journal of Korean Association for Spatial Structures
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• v.14 no.2
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• pp.59-68
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• 2014

A study on the vibration and buckling analyses of laminated composite plates is described in this paper. In order to carry out the analyses of laminated composite plates, a NURBS-based isogeometric general plate element based on Reissner-Mindlin (RM) theory is developed. The non-uniform rational B-spline (NURBS) is used to represent the geometry of plate and the unknown displacement field and therefore, all terms required in this element formulation are consistently derived by using NURBS basis function. Numerical examples are conducted to investigate the accuracy and reliability of the present plate element. From numerical results, the present plate element can produce the isogeometric solutions with sufficient accuracy. Finally, the present isogeometric solutions are provided as future reference solutions.