• Journal of Korea Foundry Society
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• v.11 no.3
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• pp.245-253
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• 1991

It is known that the analysis of thermal stresses is substantially important in optimal design of casting mould. In this paper unsteady state thermal stresses generated in ingot and mould during the solidification process are analyzed by the two dimensional thermal elasto-plastic analysis. Distribution of temperature and stress of the mould is calculated using the finite element method and compared with experimental result. The significant results obtained in this study are as follows. At the early stage of the casting process, abrupt temperature change was shown in the vicinity of the inner surface of the mould. The largest temperature gradient is occurred at the corner of the mould. In the thermal stress analysis, compressible stress occurred in the inside wall of the mould where as tensile stress on outside wall. Smaller thermal stress is observed at the rounded corner. It is also observed that the shown is influenced by the thickness of the wall. A fairly good coincidence is found between analytical and experimental results, showing that the proposed analytical methodology is reliable.

• Korean Journal of Child Studies
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• v.29 no.6
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• pp.105-119
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• 2008

Investigating cross-cultural differences of family stress and adaptation in Korea and Australia, 49 families in open adoption were administered the Family Index of Regenerativity and Adaptation-General (McCubbin, 1987), Family Problem Solving Communications (McCubbin et al., 1988), and Social Support Index (McCubbin et al., 1982). Data were analyzed by T-test and correlation analysis. Results indicated that adoption itself was the primary stressor in both countries. Korean adoptive families were under stress by family-oriented factors; Australian adoptive families experienced external family stress. Regarding family hardiness, coping efforts and family communication, Australian adoptive families reported significantly higher family functioning than Korean adoptive families. Findings suggested that a broad range of social support is needed to improve family adaptability in both countries.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.2 no.1
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• pp.22-31
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• 2003

The compressive residual stress, which is induced by shot peening process, seems to be an Important factor in increasing the fatigue strength. And then it was showed that residual stress was disappearenced at the high temperature. The fatigue charateristic investigation of a SUP9 spring steel processed shot peening is performed by considering the high temperature service conditions in the range of room temperature through $180^{\circ}C$ in the range of stress ratio of 0.3 by means of opening mode displacement. The fatigue resistance characteristics and fracture strength at high temperature is considerable lower than that of room temperature in the early stage and stable of fatigue crack growth region.

• Korean Journal of Child Studies
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• v.34 no.4
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• pp.143-162
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• 2013

The purpose of this study was to investigate factors which influence the degrees of parenting stress experienced by mothers within multicultural famiiles. This study will provide basic data which can be used to develop services and programs for multicultural families. The data were collected utilizing questionnaires administered to 155 mothers of multicultural families. The data were analyzed by means of ANOVA, Pearson's correlation and multiple regression using the SPSS 18.0 program. The results were as follows : Firstly, the educational level, self-esteem, depression, and marital satisfaction of the mother are factors that significantly influence a mother's parenting stress within the context of a multicultural family. Secondly, the mother's psychological factor, including her self-esteem and depression, and the mother's educational level were the clearest indicators for their relative level of their parenting stress.

• The Korean Journal of Community Living Science
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• v.19 no.4
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• pp.547-558
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• 2008

The purpose of this study was to identify a couple's parental efficacy combination and, then, analyze parental role-sharing and parenting stress according to this combination type. The subjects were 307 couples who have a child in 1st or 2nd grade. The main results were as follows: First, fathers and mothers, as a group, did not differ in terms of parental efficacy. Secondly, some demographic variables related to parental efficacy. Thirdly, there are more couples who have similar levels of parental efficacy than those who have different levels of parental efficacy. Fourth, no significant difference in parental role-sharing was found among the 4 types of couple's parental efficacy. Fifth, mothers had low parental stress when both of the couple had high levels of parental efficacy while fathers perceived low parental stress if only he, himself, had a high level of parental efficacy.

• Korean Journal of Childcare and Education
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• v.12 no.3
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• pp.1-19
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• 2016

The purpose of this study was to examine the effect of parenting efficacy measured at 6 months of infancy, and on parenting stress at 9-months of infancy through a short-term longitudinal approach. Participants were 116 couples living in Seoul and Gyeonggi-do, whose first born children were in infancy. The results of the 116 couples were analyzed through the APIM analysis method. The results of the APIM showed that mothers' and fathers' actor effect was significant, which meant that parenting efficacy at 6 months of infancy could predict the existence of parenting stress at 9 months of infancy. However, the partner effect of both mothers and fathers was insignificant. This research demonstrates the significance of parenting efficacy at early infancy, which in turn affects parenting stress as well as factors that need to be considered in pre-parental education.

• Proceedings of the KSME Conference
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• 2001.06a
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• pp.591-596
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• 2001

The purpose of this study is to examine the change of half value breadth and residual stress during fatigue process in S45C Steel by X-ray diffraction. For S45C Steel, the relationship between the change in fatigue damage of the specimen and the half value breadth, and residual stress of X-ray diffraction profiles during the fatigue processes has been investigated. The half value breadth(HVB) decreases in he early period of fatigue cycle. The change of HVB is relation to cyclic work hardening. In $10{\sim}20%$ of ratio of fatigue life, the change in the half value breadth is not marked. During fatigue process, the residual stress is changed with fatigue cycle increasing.

• Korean Journal of Child Studies
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• v.27 no.1
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• pp.17-30
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• 2006

The goal of this research was to clarify how a child's maladjustment affects the teacher-child relationship and leads to teaching stress. Subjects were 178 teacher-child pairs in kindergartens or day care centers. The child was 3 to 5-years-old and perceived by its teacher as having maladjusted behavior. Teachers responded to the Index of Teaching Stress(Greene, Abidin, & Kmetz, 1997) and the Student-Teacher Relationships Scale(Pianta 1991). The maladjusted behaviors observed by teachers were correlated with each other. ADHD was the biggest problem perceived by teachers. Most fields of maladjusted children's behaviors caused stress to teachers except those of intellectual deficit and academic Problems. Frustration peaked during the teaching process. More severely maladjusted behaviors resulted in greater conflict in teacher-child relationships.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.43 no.7
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• pp.1121-1127
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• 1994

The accelerated degradation phenomena in amorphous silicon thin film transistors due to both electrical stress and visible light illumination under the elevated temperature have been investigated systematically as a function of gate bias, light intensity, and stress time. It has been found that, in case of electrical stress, the thrshold voltage shifts of a-Si:H TFT's may be attributed to the defect creation process at the early stage, while the charge trapping phenomena may be dominant when the stressing periods exceed about 2 hours. It has been also observed that the degradation in the device characteristics of a-Si:H TFT's is accelerated due to multiple stress effects, where the defect creation mechanism may be more responsible for the degradation rather than the charge trapping mechanism.

• Journal of the Korean Home Economics Association
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• v.40 no.10
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• pp.191-200
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• 2002

The purpose of the study was to investigate parenting stress of mothers with handicapped children. The study employed an ecological model. Data were collected from 142 mothers of handicapped children enrolled in early childhood education classes at welfare facilities in Seoul, Korea. The main results of the study were as follows: 1. The parenting stress of subject mothers was at a severe level. 2. The hierarchical regression analysis yielded the results that mother's depression(β=.383, p<.001), the degree of child's handicap(β=.307, p<.001), child's age(β=.274, p<.01), and mother's participation at parent education program(β=.176, p<.05) were significant factors in explaining mothers' parenting stress. The research model explained 45% of variance.