• Proceedings of the KSR Conference
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• 1999.05a
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• pp.352-357
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• 1999

During the cooling process of rail, residual stresses are produced due to the difference of the coefficients of thermal expansion between rail and inhomogeneous non-metallic inclusions such as sulphides and oxides. A micro-mechanical approach is used to obtain the stresses in the inclusions and matrix, After obtaining the stress of an elliptical inhomogeneous inclusion in an infinite domain, average stresses of randomly distributed spherical inclusions are obtained by use of Mori-Tanaka's self consistent method. The magnitude of the calculated residual stress is near to the yield stress of the matrix in case of the spherical inclusions.

• Child Health Nursing Research
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• v.11 no.3
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• pp.290-300
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• 2005

Purpose: The purpose of this study was to identify the factors influencing parenting stress in primiparas. Method: The participants in this study were 198 primiparas of infants aged 1-6 months who visited well baby clinics in 5 hospitals. The data were collected from April 15 to June 15, 2003. Results: The mean score for parenting stress was 2.4 of a possible 5 and thus considered average. The score for parenting stress was significantly correlated with the level of maternal perception of the infant and the level of social support. The score for parenting stress was significantly different according to the education level of the primiparas and prenatal management. For the primiparas, social support($20\%$) and maternal perception of the infant($9\%$) were significant predictors explaining parenting stress. Conclusions: Nursing interventions to improve maternal perception of the infant and increase social support should be provided for primiparas in order to reduce parenting stress.

• Journal of Korean Academy of Nursing Administration
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• v.17 no.2
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• pp.216-225
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• 2011

Purpose: In this study, the relationship between self-leadership, stress, and satisfaction among nursing students in clinical practice was examined. Method: The participants were 273 nursing students. Data collected from September to December 2010 were analyzed using descriptive statistics, t-test, ANOVA, Pearson correlation coefficients, and stepwise multiple regression. Results: The mean scores for self-leadership ($3.72{\pm}.41$), stress ($3.45{\pm}.59$), and satisfaction ($3.11{\pm}.38$) in clinical practice were above average. Self-leadership was significantly different according to year, interpersonal relationships, and satisfaction with nursing as a major. Stress in clinical practice was significantly different according to gender, year, and health status. Satisfaction in clinical practice was significantly different according to year, interpersonal relationships, and satisfaction with nursing as a major. Significant correlations were found between self-leadership and satisfaction in clinical practice, and stress and satisfaction in clinical practice. Year, self-leadership, interpersonal relationships, and stress in clinical practice were factors influencing satisfaction in clinical practice (20.0%). Conclusion: These findings indicate that there is a need to improve self-leadership, and to lessen stress in clinical practice to improve nursing students' satisfaction with clinical practice. The above-mentioned results should be reflected in the development of effective teaching methods for clinical practice.

• Journal of muscle and joint health
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• v.14 no.1
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• pp.5-12
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• 2007

Purpose: The purpose of the study was to identify the relationship between low back pain and job stress in hospital nurses. Method: A descriptive correlation research design was employed. The participants were 355 nurses who worked in a general hospital in W city Kangwon-do and consented to participate in this study. The Visual Analog Scale and job stress scale were used in this study. Analysis included descriptive statistics, t-test, ANOVA, and partial correlation coefficients. Results: Experience of low back pain for nurse in the past was 86.5% and in the present was 67.5% for low back pain which measured an average of 4.4 points for the level of low back pain. The mean score for job stress was relatively low(M=47.2). Job demand, organization system, job instability and conflict in relationships contributed to high stress scores, instead inappropriate compensation, job culture, and job autonomy contributed to low stress. There was a significant relationship between low back pain and job stress. Conclusion: These results suggest that further research is needed to develop programs to prevention and management of low back pain for nurses.

• Journal of Aerospace System Engineering
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• v.13 no.6
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• pp.1-8
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• 2019

The synthetic turbulence generation model for inlet boundary conditions of subsonic Backward Facing Step (BFS) was investigated. The average u-velocity and Reynolds stress at inlet boundary follows experimental data. Synthetic Eddy Method (SEM), random noise, and uniform flow conditions were implemented relative to the synthetic turbulence generation method. A three dimensional Large Eddy Simulation (LES) was applied for turbulent flow simulation. Turbulent and mean flow characteristics such as flow reattachment length, velocity profiles, and Reynolds stress profiles of BFS were compared with respect to the turbulent effects.

• Earthquakes and Structures
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• v.7 no.5
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• pp.647-665
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• 2014

Squat reinforced concrete walls require enough shear strength in order to promote flexural yielding, which creates the need for designers of an accurate method for strength prediction. In many cases, especially for existing buildings, strength estimates might be insufficient when more accurate analyses are needed, such as pushover analysis. In this case, estimates of load versus displacement are required for building modeling. A model is developed that predicts the shear load versus shear deformation of squat reinforced concrete walls by means of a panel formulation. In order to provide a simple, design-oriented tool, the formulation considers the wall as a single element, which presents an average strain and stress field for the entire wall. Simple material constitutive laws for concrete and steel are used. The developed models can be divided into two categories: (i) rotating-angle and (ii) fixed-angle models. In the first case, the principal stress/strain direction rotates for each drift increment. This situation is addressed by prescribing the average normal strain of the panel. The formation of a crack, which can be interpreted as a fixed principal strain direction is imposed on the second formulation via calibration of the principal stress/strain direction obtained from the rotating-angle model at a cracking stage. Two alternatives are selected for the cracking point: fcr and 0.5fcr (post-peak). In terms of shear capacity, the model results are compared with an experimental database indicating that the fixed-angle models yield good results. The overall response (load-displacement) is also reasonable well predicted for specimens with diagonal compression failure.

• Korean Medical Education Review
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• v.25 no.3
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• pp.243-257
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• 2023

This study aimed to analyze trends in research on depression among medical students in Korea and to conduct a meta-analysis to determine the average correlation coefficients between depression and related variables. In total, 38 quantitative studies (four theses and 34 journal articles) published between January 1995 and February 2023 were analyzed according to publication year, subjects, analysis methods, and measurement tools. Among them, 15 studies that provided numerical information on the relationships between depression and variables such as self-esteem, social support, grade point average (GPA), stress, and academic stress were selected for meta-analysis. The main findings of this study were as follows. First, quantitative research on depression among medical students began in earnest in 2009, and cross-sectional studies targeting first-year and second-year medical students were the most prevalent. Furthermore, the most commonly used analysis method was difference testing, and the Beck Depression Inventory was the most frequently used measurement tool. Second, the mean correlation coefficients between depression and stress, self-esteem, social support, academic stress, and GPA were 0.534, 0.532, 0.465, 0.390, and 0.102, respectively. The results for self-esteem, stress, and academic stress showed substantial heterogeneity, while those for social support and GPA showed little heterogeneity. These findings suggest that educational interventions, such as social support improvement programs, are necessary to prevent depression among medical students.

• Journal of dental hygiene science
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• v.9 no.2
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• pp.219-224
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• 2009

The purpose of this study was to investigate the relationship among the stress on clinical practice, stress coping method and the somatization symptom of dental hygiene students and propose strategies for effective instruction of clinical practice. The survey was performed by self-reported questionnaires for 268 dental hygiene students who have recently experienced clinical practice. Collected data were analyzed using by t-test and Pearson correlation coefficient with the SPSS Win 12.0 program. Its results are as follows. 1. In the satisfaction of clinical practice, 'Satisfaction', 'Average' and 'Unsatisfactory' were 32.5%, 42.2% and 25.4%, respectively. The reason for dissatisfaction of clinical practice were 'insufficient education of college'(29.8%), 'environment of clinical practice institute'(23,4%), 'interpersonal relationship'(21.3%) in order. 2. Somatization symptoms was positive correlation(0.307, p < 0.01) associated with stress of clinical practice. Also it was negative correlation associated with satisfaction level of the subjects and stress of clinical practice. Correlation coefficient of the interpersonal relation factor was found the most significantly high as much as 0.331, according to the analysis carried out between subordinate factors of clinical practice stress and somatization. 3. According to stress coping method. Subjects were distributed into two group of active method and passive method. Thereafter as a result of verifying the difference of somatization symptoms, there was statistically significant difference between active method group and passive method group. Based on the study results, we suggests that effective management program of clinical practice should be developed and applied to the dental hygiene students to make them cope with stress and somatic symptom during their clinical practice.

• Transactions of Materials Processing
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• v.8 no.1
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• pp.108-115
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• 1999

In this paper, the analysis of cold forging in final state has been performed by using rigid-plastic FEM. For the analysis, the geometry and flow stress of the workpiece are required. One method to obtain the geometry is measurement of that made from experimet. To evaluate the flow stress, average effective strain is calculated from the load-stroke diagram by using energy method. The numerical test performed to show the validity of propose method. The analysis of PFIR, the precision forging of spurgear with inside relif, is performed.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.10
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• pp.2518-2534
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• 1993

Fracture behavior of carbon/epoxy laminates under pin loading is studied experimentally and analytically. Effects of ratios of specimen width to hole diameter and edge distance to hole diameter on bearing strength are investigated. Characteristic length of the laminates obtained using HK model has good agreement with the experimental data. The larger hole size induced, the lower bearing strength is measured under pin loading . The bearing strength and failure mode could be predicted using HK model and Zhangs analytical solution of stress distribution around a pin loaded hole. Chamis' prediction method of bearing strength is also considered to predict failure mode and bearing strength. A modification of Chamis' method is made using the factor of rupturc. The predicted bearing strength by the modified method is reasonably close to the experimental data.