• Korean Journal of Childcare and Education
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• v.13 no.4
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• pp.1-17
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• 2017

Objective: The purpose of this study was to examine the relationships among young children's temperament, emotional regulation, and their mother's parenting stress. This study also analyzed the mediating effect of mother's parenting stress on the relationship between the other two variables. Methods: A total of 304 mothers with young children that lived in Gwangju and Jeollanamdo participated in this study. The data were analyzed using Pearson's correlation coefficient, hierarchical multiple regression analysis, and the Sobel test. Results: The main results are as follows. First, adaptability temperament was positively correlated with children's emotional regulation and negatively correlated with mother's parenting stress. There was no statistically significant relationship between activity temperament and other variables, whereas regularity temperament had only a significant relationship with emotional regulation. Second, it was found that mother's parenting stress partially mediated between children's adaptability temperament and emotional regulation. Conclusion: The results of this study imply that mother's parenting stress is a very important factor on young children's emotional regulation. Also, the present study suggests that children's adaptability temperament and mother's parenting stress should be considered together in order to improve young children's emotional regulation.

• Journal of Biosystems Engineering
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• v.40 no.4
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• pp.335-344
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• 2015

Purpose: Soybean growth is adversely affected by environmental stresses such as drought, extreme temperatures, and nutrient deficiency. The objective of this study was to develop a method for rapid measurement of drought stress in soybean plants using a hyperspectral fluorescence imaging technique. Methods: Hyperspectral fluorescence images were obtained using UV-A light with 365 nm excitation. Two soybean cultivars under drought stress were analyzed. A partial least square regression (PLSR) model was used to predict drought stress in soybeans. Results: Partial least square (PLS) images were obtained for the two soybean cultivars using the results of the developed model during the period of drought stress treatment. Analysis of the PLS images showed that the accuracy of drought stress discrimination in the two cultivars was 0.973 for an 8-day treatment group and 0.969 for a 6-day treatment group. Conclusions: These results validate the use of hyperspectral fluorescence images for assessing drought stress in soybeans.

• International Journal of Concrete Structures and Materials
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• v.10 no.2
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• pp.221-236
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• 2016

The aim of this paper is to investigate the compressive behavior and characteristics of amorphous metallic fiber-reinforced concrete (AMFRC). Compressive tests were carried out for two primary parameters: fiber volume fractions ($V_f$) of 0, 0.3, 0.6 and 0.8 %; and design compressive strengths of 27, 35, and 50 MPa at the age of 28 days. Test results indicated that the addition of amorphous metallic fibers in concrete mixture enhances the toughness, strain corresponding to peak stress, and Poisson's ratio at high stress level, while the compressive strength at the 28-th day is less affected and the modulus of elasticity is reduced. Based on the experimental results, prediction equations were proposed for the modulus of elasticity and strain at peak stress as functions of fiber volume fraction and concrete compressive strength. In addition, an analytical model representing the entire stress-strain relationship of AMFRC in compression was proposed and validated with test results for each concrete mix. The comparison showed that the proposed modeling approach can properly simulate the entire stress-strain relationship of AMFRC as well as the primary mechanical properties in compression including the modulus of elasticity and strain at peak stress.

• Journal of the Korean Society of Safety
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• v.29 no.5
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• pp.88-96
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• 2014

Each year, it seems inevitable that major accidents will occur on construction sites. Industrial accidents, sometimes involving foreign laborers, have been constantly increasing. Construction laborers have higher hazard rates and higher work intensity than other industries, which means that they experience more job stress, as a result of the subcontracting structure. Therefore, this study performed an influence factor analysis on job stress and its relevance to industrial accidents involving Korean and foreign construction laborers, and proposed its effectiveness with the job stress and construction accident management measures based on the results of those. A questionnaire to measure job stress was performed targeting Korean and foreign laborers, and the results were analyzed. The results of this study can be utilized as important reference materials in efforts to reduce the job stress of foreign laborers on construction sites, and can be expected to contribute to preventing construction accidents related to job stress in the future.

• Geomechanics and Engineering
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• v.8 no.3
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• pp.441-460
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• 2015

A new theoretical approach for analysis of stress around a tensioned anchor in rock is presented in this paper. The solution has been derived for semi-infinite elastic rock and anchor and for plane strain conditions. The method considers both the anchor head bearing plate and its grouted bond length embedded in depth. The solution of the tensioned rock anchor problem is obtained by superimposing the solutions of two simpler but fundamental problems: A distributed load applied at a finite portion (bearing plate area) of the rock surface and a distributed shear stress applied at the anchor-rock interface along the bond length. The solution of the first problem already exists and the solution of the shear stress distributed along the bond length is found in this study. To acquire a deep understanding of the stress distribution around a tensioned anchor in rock, an illustrative example is solved and stress contours are drawn for stress components. In order to verify the results obtained by the proposed solution, comparisons are made with finite difference method (FDM) results. Very good agreements are observed for the teoretical results in comparison with FDM.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.21 no.4
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• pp.466-474
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• 2014

Purpose: The purpose of this study was to identify the relationship between emotional intelligence and stress coping of nurses in hospitals. Method: The study was a descriptive-correlational study with a convenience sample of 298 nurses. Descriptive statistics t-test, Mann-Whitney U, One-way ANOVA and Pearson correlation coefficients were used for data analysis. Results: The results of this study were as follows; Emotional intelligence was higher in married nurses than unmarried nurses (t=-2.90, p=.004). Nurses with a clinical career of 4~7 years had better stress coping than nurses with shorter careers (F=5.60, p=.004). Ward nurses better stress coping than nurses in emergency rooms and Intensive care units (F=4.43, p=.013). Fixed shift nurses had better stress coping than nurses on rotation shifts (t=-2.37, p=.019). There was a significant positive correlation between emotional intelligence and stress coping(r=.29, p<.001). Conclusion: The results indicate that stress coping is better in nurses with higher emotional intelligence, 4~7 year clinical experience, working on ward a as well as having a fixed shift. However further development and application of programs which can improve nurses' emotional intelligence are needed.

• Journal of Ocean Engineering and Technology
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• v.25 no.5
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• pp.47-51
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• 2011

This paper analyzes the fatigue-life of welded joints using the notch stress approach. In the notch stress approach, the notch effects are usually approximated by introducing weld-bead parameters for the local detailed weld joints. The actual bead shape is complex and 3-dimensional. It may also greatly influence the fatigue strength. In this study, the welded shape was modeled using a 3D-scanner. The critical distance method was adopted in the evaluation of the fatigue effective notch stress for the weldments. Fatigue life tests were performed to verify the present method of fatigue life estimation for two types of welded plates with longitudinal attachments. The estimated results of the present methods were applied to the results of the experiment. The results of the analysis showed that the scatter of fatigue-life for the experimental data expressed in the nominal stress was significantly reduced by applying the effective fatigue stress of the present study.

• Structural Engineering and Mechanics
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• v.36 no.5
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• pp.575-598
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• 2010

The shape and size of the plastic zone around the crack tip are analyzed under pure mode I, pure mode II and mixed mode (I+II) loading for small scale yielding and for both plane stress and plane strain conditions. A new analytical formulation is presented to determine the radius of the plastic zone in a non-dimensional form. In particular, the effect of T-stress on the plastic zone around the crack tip is studied. The results of this investigation indicate that the stress field with a T-stress always yields a larger plastic zone than the field without a T-stress. It is found that under predominantly mode I loading, the effect of a negative T-stress on the size of the plastic zone is more dramatic than a positive T-stress. However, when mode II portion of loading is dominating the effect of both positive and negative T-stresses on the size of the plastic zone is almost equal. For validating the analytical results, several finite element analyses were performed. It is shown that the results obtained by the proposed analytical formulation are in very good agreements with those obtained from the finite element analyses.

• Journal of Korean Public Health Nursing
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• v.30 no.3
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• pp.470-482
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• 2016

Purpose: The purpose of this study was to investigate the moderated effects of coping strategies in the relationship between life stress and psychological well-being in university students. Methods: Self-report questionnaires were used to collect the data from 278 university students. The data were analyzed using descriptive statistics, pearson correlation coefficient and hierarchial multiple regression. Results: Psychological well-being is negatively associated with life stress and avoidance coping, and positively associated with problem solving coping. Results showed that there were significant moderated effects of coping strategies in the relationship between life stress and psychological well-being. Under high life stress levels with high problem solving coping and low avoidance coping, there was a high level of psychological well-being. Moreover, life stress and coping strategies interacted well with each other to affect psychological well-being. A negative correlation between life stress and psychological well-being was remarkable for the high problem solving coping group and high avoidance coping group. Conclusion: The study results suggest that in order to improve psychological well-being, it is necessary to provide intervention programs to promote problem solving coping and to reduce the avoidance coping for university students.

• Korean Journal of Childcare and Education
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• v.16 no.6
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• pp.89-104
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• 2020

Objective: The purpose of this study was to examine the effects of maternal parenting stress and mother's ego-resilience on mother-child attachment. More specially, mother-child attachment for higher grade elementary school children was examined according to the internal working model. Methods: Participants were 190 mothers of fourth and fifth grade elementary school children. The Maternal Parenting Stress Scale(Shin, 1997), the Scales of Ego-resilience(Yoo & Shim, 2002), and Inventory of Parent Attachment(Yang, 2006) were used to measure variables. Collected data were analyzed by descriptive statistics, t-test, correlation analysis and multiple regression analysis. Results: The major findings were summarized as follows: First, there were no differences between mother-child attachment according to children's gender. Second, mother-child attachment was negatively correlated with maternal parenting stress and positively correlated with ego-resilience. Next, maternal parenting stress_interaction and ego-resilience explained mother-child attachment_trust. Last, maternal stress_interaction explained mother-child attachment_isolation. Conclusion/Implications: In conclusion, the study results showed that maternal parenting stress and ego-resilience influenced mother-child attachment. based on the results, the implications of this study were discussed.