• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.3
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• pp.137-143
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• 2008

For most bearings, it is a common requirement to have long durability. Especially wheel bearing fatigue life is the most important in automotive quality. The contact fatigue life analysis of automotive wheel bearing considering real raceway rough surface is presented in this paper. Contact stresses are obtained by contact analysis of a semi-infinite solid based on the use of influence functions; the subsurface stress field is obtained using rectangular patch solutions. Mesoscopic multiaxial fatigue criterion which can yield satisfactory results for non-proportional loading is then applied to predict fatigue damage. Suitable counting method and damage rule were used to calculate the fatigue life of random loading caused by rough surface. The life analysis considering real rough surface of wheel bearing raceway is in good agreement with the experimental results.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.1125-1131
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• 2009

This paper presents the evaluation of fatigue life for a journal box attached to rolling stock bogie under random dynamic loading condition. Because a journal box was under random dynamic loading conditions, the fatigue life assessment due to these loads requires the analysis considering the multiaxial effect of random dynamic loading. To do this work, the finite element analysis has been conducted to calculate random dynamic response using multiaxial acceleration data. Then, the fatigue life assessment of component has been conducted using vibration fatigue analysis applying the power spectral densities of the responses obtained through the FEA The results of fatigue life assessment were compared to the damage from the strain measurement. This study shows that can be evaluated the fatigue life assessment considering real service condition about a component attached to rolling stock bogie.

• Journal of the Korean Home Economics Association
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• v.25 no.2
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• pp.89-107
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• 1987

This study aimed at providing basis data to understand homemanagement by patterning of the life styles of housewives and by analysing the disposition of homemanagement behavior and characterstics of the behavior pattern to the difference of the life style patterns of housewives. The result can be summarized as follows: 1. By utilizing factor analysis and cluster analysis, the life style types of housewives were classified into 4 types, namely, self-fulness type (28.4%), negative stagnation type (22.7%), fashion-convenience type (23.3%), innovation-urging type (25.6%). 2. The life style types of housewives which were classified, differed significantly according to all of the demographic variables except family size variable. 3. The disposition of homemanagement behavior which were classified into inner-directed type and other-directed type, differed significantly according to the husband's age variable. 4. The patterns of homemanagement behavior which were classified into market pattern and service pattern, differed significantly according to the all of the demographic variables. 5. The disposition and the pattern of homemanagement behavior differed significantly according to the life style types of housewives.

• Journal of the Korean Home Economics Association
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• v.29 no.4
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• pp.99-114
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• 1991

This study was designed to determine the relative importance of specific family environmental variables and positive self-concept of psychological variables in explaining family life satisfaction. Data were collected from 423 housewives in Daegu City. Multivariate regression and factor analysis and path analysis were used to analyze the data. The results of this study partially supported the hypothesis that positive self-concept of psychological factors would be more closely associated with family life satisfaction than would family environmental factors. The findings were as follows: 1. Urban housewives' positive self-concept and family life satisfaction were relatively high. 2. Among family environment variables, health, wives' education level, husband's satisfaction with job significantly influence on positive self-concept. 3. The variables which significantly affect family life satisfaction are husband's satisfaction with job, monthly family income, health. 4. From the path analysis, it found that positive self-concept has the most great influence on family life satisfation.

• Journal of the Korean Data and Information Science Society
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• v.16 no.2
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• pp.237-253
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• 2005

In Korea, the volume of insurance industry has been increased rapidly with helping the economic growth, the increment of GNP and derive of public welfare policy. But the other side of the volume increment, the life insurers have some problems, such as the high rate of turnover, lapses and surrenders, in processing of acquiring more insurance contracts. The object of this paper is the analysis of the causes and properties of the high rate of turnover, lapses and surrenders using statistical survival model. Also we hope that the insurers will use the results of analysis to reduce the rates.

• Journal of Agricultural Extension & Community Development
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• v.27 no.3
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• pp.111-124
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• 2020

This study begins with an interest in community capacity, the basis for mobilizing community action and the driving force of community development. The study aims to identify the structural equation model of community capacity, social participation, satisfaction in life, and the impact relationship and to verify the differences between urban and rural areas. The analysis data used the 2018Korean Social Integration Survey, which is the statistical data for national approval. The analysis method was performed by using SPSS was used to perform descriptive analysis and t-test, and the structural equation model. Multi-group analysis of AMOS was also performed to verify the research model. As the result of analysis, both the condition and status of community capacity and social participation, which are products of community capacity, showed a higher average of rural areas than urban areas. As a result of the analysis of the structural equation model between community capacity, social participation, and life satisfaction, differences between rural and urban groups were identified. In rural areas, both the capacity-condition and the capacity-status variables act as positive factors for social participation and life satisfaction, but in urban areas, the path of capacity-condition, social participation, capacity-status and life satisfaction was significant. On the other hand, social participation variables acted as a factor of direct and indirect negatively influence on life satisfaction. Therefore, it can be said that the quality of community capacity in rural areas is superior to that of urban areas.

• Journal of Digital Convergence
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• v.15 no.6
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• pp.97-105
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• 2017

The subjects were 500 college students in 7 provincial areas for the study on the structural relation among professors' core competency, college students' cognitive learning competency and life competencies. The statistical methods of this study were as follows: frequency analysis, descriptive statistic analysis, exploratory factor analysis, reliability analysis, correlation analysis, confirmatory factor analysis, and structure equation model analysis. The results of the study are as follows. First, the lifelong learning educators' college students recognized core competency significantly affects on the college students' life competencies. Second, the lifelong learning educators' core competency significantly affects on the college students' cognitive learning competency. Third, the college students' cognitive learning competency significantly affects on life competencies. Fourth, the college students' cognitive learning competency has a significant mediating effect between the lifelong learning educators' core competency and the college students' life competencies. In other words, the lifelong learning educators' core competency based on the college students' cognitive learning competency has great effect on life competencies.

• Journal of Korean Society of Water and Wastewater
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• v.29 no.1
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• pp.11-21
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• 2015

When designing Water Distribution System (WDS), determination of life cycle for WDS needs to be preceded. And designer should conduct comprehensive design including maintenance and management strategies based on the determined life cycle. However, there are only a few studies carried out until now, and criteria to determine life cycle of WDS are insufficient. Therefore, methodology to determine life cycle of WDS is introduced in this study by using Life Cycle Energy Analysis (LCEA). LCEA adapts energy as an environmental impact criterion and calculates all required energy through the whole life cycle. The model is build up based on the LCEA methodology and model itself can simulate the aging and breakage of pipes through the target life cycle. In addition the hydraulic analysis program EPANET2.0 is linked to developed model to analyze hydraulic factors. Developed model is applied to two WDSs which are A WDS and B WDS. Model runs for 1yr to maximum 100yr target life cycle for both WDSs to check the energy tendency as well as to determine optimal life cycle. Results show that 40yr and 54yr as optimal life cycle for each WDS, and tendency shows the effective energy is keep changing according to the target life cycle. Introduced methodology is expected to use as an alternative option for determining life cycle of WDS.

• Journal of Fisheries and Marine Sciences Education
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• v.29 no.2
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• pp.365-379
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• 2017

The purpose of this study was to test the mediated effects of emotional regulation in the relations between maternal parenting and children's adaptation to school life of elementary school students. Three-hundred Seven elementary school students completed the maternal parenting scale, the emotional regulation scale, and the adaptation to school life scale. In order to find to identify how maternal parenting, emotional regulation were related with their adaptation to school life, Pearson correlation coefficients were used in the computation. To examine the effects of maternal parenting, emotional regulation on adaptation to school life, multiple regression analyses were conducted. To examine whether emotional regulation as a mediating variable in the process that maternal parenting is influencing children's adaptation to school life, hierarchical regression analyses were performed. The results of this study were summarized as follows. First, the analysis of the relationship of maternal parenting, emotional regulation with adaptation to school life shows that there is a significant positive correlation between maternal parenting, emotional regulation and adaptation to school life. Second, in the multiple regression analysis with maternal parenting and emotional regulation as a predictor and adaptation to school life as an outcome variable it has been shown that the emotional regulation were significant in adaptation to school life, but maternal parenting were not significant in adaptation to school life. The higher the emotional regulation is the better can children adapt themselves to school life. Third, the analysis on the mediating effects of emotional regulation in the relationship of maternal parenting and adaptation to school life showed that emotional regulation full mediates the relationship of maternal parenting with adaptation to school life.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.6
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• pp.757-766
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• 2019

Objective: MicroRNAs are a class of endogenous small regulatory RNAs that regulate cell proliferation, differentiation and apoptosis. Recent studies on miRNAs are mainly focused on mice, human and pig. However, the studies on miRNAs in skeletal muscle of sheep are not comprehensive. Methods: RNA-seq technology was used to perform genomic analysis of miRNAs in prenatal and postnatal skeletal muscle of sheep. Targeted genes were predicted using miRanda software and miRNA-mRNA interactions were verified by quantitative real-time polymerase chain reaction. To further investigate the function of miRNAs, candidate targeted genes were enriched for analysis using gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) enrichment. Results: The results showed total of 1,086 known miRNAs and 40 new candidate miRNAs were detected in prenatal and postnatal skeletal muscle of sheep. In addition, 345 miRNAs (151 up-regulated, 94 down-regulated) were differentially expressed. Moreover, miRanda software was performed to predict targeted genes of miRNAs, resulting in a total of 2,833 predicted targets, especially miR-381 which targeted multiple muscle-related mRNAs. Furthermore, GO and KEGG pathway analysis confirmed that targeted genes of miRNAs were involved in development of skeletal muscles. Conclusion: This study supplements the miRNA database of sheep, which provides valuable information for further study of the biological function of miRNAs in sheep skeletal muscle.