• 한국안전학회지
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• 제14권3호
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• pp.25-32
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• 1999

This study has been performed to investigate the stress distribution around defects that behave as stress concentrators. Besides, the effect of stress interaction effects on the initiation of primary cracks were also investigated by rotary bending fatigue tests which were performed with specimens drilled micro surface defects and the stress distribution was analyzed using Finite Element Method. In addition, the stress interaction effects around defects and cracks were investigated by comparing the results of experiments and F.E.M. The results obtained are summarized as follows ; 1) Area which slip and micro cracks initiated at micro surface defects is between the maximum shear stress points and this area is over than ${\pm}30^{\circ}$ from the maximum stress point along the defect edge. 2) The stress interaction effect for the small size defect is larger than that of large size defect when the interval between them is near 3) Interval which there is no shear stress interaction effect analyzed by F.E.M. is larger than that of experimental results.

• 대한기계학회논문집
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• 제19권5호
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• pp.1259-1268
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• 1995

The stress distribution around micro holes and the behavior of stress interaction between micro holes are considerd in the study. Several conclusions are extracted as follows : (1) The stress interaction varies with the distance e between micro holes. When the two micro holes are spaced in such a manner that theri two closest points are separated by a distance of micro hole radius (e=1), stress distribution is affected by a opposite micro hole in all the closest region. In addition, if two closest points are seperated by twice the distance of a micro hole radius (e=2), stress distribution is affected by a opposite micro hole in the region of -0.8.leq.x/r.leq.0.8 and the interaction effect can be neglected for e=4. (2)If the depth becomes larger than the radius, or the radius varies, the shape and magnitude of stress distribution around micro holes varies. (3) Hoop stress around a micro hole for the two dimensional configuration is larger than that of the three dimensional micro hole located on the surface of material for .theta. < 60.deg., but it is reversed for .theta > 60.deg.

• 대한간호학회지
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• 제47권6호
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• pp.854-863
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• 2017

Purpose: The present study is a descriptive cross-sectional study of cause-and-effect relationship, which used the $7^{th}$ year data of the Panel Study on Korean Children, to investigate the effects of parenting stress, depression, and family interactions of the parents of early school-age children on children's subjective happiness. Methods: The present study included data of 1419 pairs of parents who participated in the mother and father survey of the Panel Study on Korean Children. The effects of parenting stress, depression, and parental family interactions on children's subjective happiness were analyzed as actor and partner effects using path analysis. Results: Parenting stress had an actor effect on depression; maternal parenting stress (${\beta}=-.21$, p<.001) and depression (${\beta}=-.30$, p<.001) had an actor effect on maternal family interaction; and paternal parenting stress (${\beta}=-.18$, p<.001) and depression (${\beta}=-.17$, p<.001) had a partner effect on maternal family interaction. Paternal parenting stress was found to have an actor effect on paternal family interaction (${\beta}=-.30$, p<.001), and parental depression was found to have actor effect (${\beta}=-.23$, p<.001) and maternal depression had a partner effect on paternal family interactions (${\beta}=-.22$, p<.001). Children's subjective happiness was found to have a statistically significant relationship with maternal family interaction (${\beta}=.40$, p<.001). Conclusion: The significance of the study is in its provision of basic data for adjusting parents' family interactions that are closely related to the growth and development of children by confirming the effect of parents' parenting stress, depression, and family interaction on children's subjective happiness.

• 한국신뢰성학회지:신뢰성응용연구
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• 제17권1호
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• pp.28-37
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• 2017

Purpose: This paper proposes a procedure that may infer and identify interaction failures in a module. Methods: In design FMEA, we defined an interaction model between components and proposed a method for selecting a single component by using the standard specification classification table and four methods for choosing the related components. We also introduced the function tree for function and requirement characteristic analysis and proposed utilization of standard stress lists and 1st and 2nd stress analysis tables to determine the effect the stress analysis has on interactions. Finally, the interaction mechanism diagram was proposed and used to infer the failure mechanism. Process FMEA also established procedures in a similar way. Results: We established a procedure for predicting the failure mode due to interaction between components based on Company A's multi-step FMEA procedure. Conclusion: By applying the proposed interaction FMEA procedure to the development model, we were able to confirm the effect of the new derivation on the failure mode of interaction, which was not predicted by the existing FMEA.

• Interaction and multiscale mechanics
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• 제6권2호
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• pp.127-136
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• 2013

In this study, atomistic simulations are performed to study the effect of Al solute on the behaviour of edge dislocation in Mg alloys. After the dissociation of an Mg basal edge dislocation into two Shockley partials using molecular mechanics, the interaction between the dislocation and Al solute at different temperatures is studied using molecular dynamics. It appears from the simulations that the critical shear stress increases with the Al solute concentration. Comparing with the solute effect at T = 0 K, however, the critical shear stress at a finite temperature is lower since the kinetic energy of the atoms can help the dislocation conquer the energy barriers created by the Al atoms. The velocity of the edge dislocation decreases as the Al concentration increases when the external shear stress is relatively small regardless of temperature. The Al concentration effect on the dislocation velocity is not significant at very high shear stress level when the solute concentration is below 4.0 at%. Drag coefficient B increases with the Al concentration when the stress to temperature ratio is below 0.3 MPa/K, although the effect is more significant at low temperatures.

• Advances in materials Research
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• 제3권1호
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• pp.271-281
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• 2014

The presence of cavities in the bone cement has a great importance for the transport of antibiotics, but its existence in this material can lead to its weakening by notch effect. The aim of this study allows providing a physical interpretation to the cavities interconnection by cracks observed experimentally. The most important stress of Von Mises is localized at the cement/bone interface near the free edge which is the seat of stress concentration. The presence and interaction of cavities in this site concentrate, by notch effect, stresses which tend to the tensile fracture stress of Bone cement.

• 아동학회지
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• 제29권1호
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• pp.243-255
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• 2008

This study analyzed relations among maternal parenting behavior, infant development and parenting stress focusing on the moderating effect of parenting stress. Subjects were 30 infants and their mothers. After videotaping the mother-infant free play session, maternal parenting was analyzed by the Parent Child Interaction Play Assessment(Mash & Terdal, 1981); mothers' parenting stress was measured by questionnaire. Infant development was measured individually by the Korean Bayley Scale of Infant Development (K-BSID-II). Correlation analyses revealed that infant cognitive development correlated significantly with maternal parenting behavior (attention) but the relation between them was moderated by maternal parenting stress; only the low parenting stress group showed a positive relationship between maternal parenting behavior and infant development.

• 가정과삶의질연구
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• 제25권1호
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• pp.45-58
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• 2007

This study explored the impact of couple interaction behaviors on the relationship between economic stress and marital instability. The study results showed that economic satisfaction and economic pressure greatly influenced the marital instability of married males and females. However, the interaction behaviors of couples tended to have a stronger impact on marital instability than economic stress. In other words, perceived spouse support and perceived spouse hostility had a significant impact on marital instability, with perceived spouse hostility being the more damaging of the two. The study also showed that there were sender differences regarding the impact of couple interaction behaviors on marital instability and economic stress. For married males, economic satisfaction as well as couple interactions influenced significantly on their marital instability. For females the impact of couple interactions on their marital instability tended to be more salient. On the whole, the results of the interaction effects between economic stress and couple interaction behaviors on marital instability did not appear significant, except in the case of females' perceived spouse hostility and its effect on marital instability.

• 한국정밀공학회지
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• 제12권2호
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• pp.154-161
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• 1995

In order to analysis of the stress distribution around flaws and the interaction effects between fatigue cracks, stress around micro hole was analyzed by Finite Element Method(F.E.M.) and micro hole specimens were tested using rotary bending fatigue machine and twisting fatigue machine to identify stress effects for fatigue cracks initiating from micro holes and interaction effects between micro holes. The results are as follows : Interaction effects of .sigma. $_{y}$for the micro hole side is larger than the large micro hole side when the interval between micro holes is near. Stress concentration factor increase as the diameter of micro hole becomes smaller. But, stress field of micro hole is smaller than that of large micro hole at h .leq. r (h:depth of micro hole, r:radius of micro hole) and that of large hole is larger than that of small micro hole at h >r expect the small range from micro hole.e.

• Nuclear Engineering and Technology
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• 제42권6호
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• pp.680-689
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• 2010

The crack-tip stress fields and fracture mechanics assessment parameters for a surface crack, such as the elastic stress intensity factor or the elastic-plastic J-integral, can be affected significantly by the adjacent cracks. Such a crack interaction effect due to multiple cracks can alter the fracture mechanics assessment parameters significantly. There are many factors to be considered, for instance the relative distance between adjacent cracks, the crack shape, and the loading condition, to quantify the crack interaction effect on the fracture mechanics assessment parameters. Thus, the current assessment codes on crack interaction effects (crack combination rules), including ASME Sec. XI, BS7910, British Energy R6 and API 579-1/ASME FFS-1, provide different rules for combining multiple surface cracks into a single surface crack. The present paper investigates crack interaction effects by evaluating the elastic stress intensity factor and the elastic-plastic J-integral of adjacent in-plane surface cracks in a plate through detailed 3-dimensional elastic and elastic-plastic finite element analyses. The effects on the fracture mechanics assessment parameters of the geometric parameters, the relative distance between two cracks, and the crack shape are investigated systematically. As for the loading condition, an axial tension is considered. Based on the finite element results, the acceptability of the crack combination rules provided in the existing guidance was investigated, and the relevant recommendations on a crack interaction for in-plane surface cracks are discussed. The present results can be used to develop more concrete guidance on crack interaction effects for crack shape characterization to evaluate the integrity of defective components.