• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.10
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• pp.1890-1899
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• 1992

In bonded structures, there are V-notched cracks in dissimilar materials and the stress concentration of these V-notched cracks causes to occur interface cracks in dissimilar materials Therefore the strength evaluation of V-notched cracks in dissimliar materials seems to be important. The stress fields of a V-notched cracks is known as .sigma.$_{ij}$ .var. K $r_{p-1}$,where K is the stress intensity factor and p-1 is the stress singularity. When the distance, r, approaches to 0 at the stress fields of V-notched cracks, the stresses become infinites by two more stress singularities of p-1 and p-1 is no more -0.5. Stress singularities and stress intensity factors for V-notched cracks in dissimilar materials are treated and discussed. The Newton-Raphson method which is an efficient numerical method for solving a non-linear equation is used for solving stress sigularities. And stress intensity factors are solved by the collocation method using the Newton-Raphson and least squares method. The effects of stress intensity factors and stress singularities on stress fields of V-notched cracks in dissimilar materials are studied by using photoelasic isochromatic frings patterns obtained from computer graphics.s.

• The Journal of the Korea Contents Association
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• v.16 no.7
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• pp.63-72
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• 2016

This study was conducted in order to identify factors influencing depression in Chinese students in Korea, focusing on factors related to acculturation stress, academic stress and career stress. The participants of this study were 166 Chinese students studying in Korea. Data were collected from Sep. 7th to Oct 15th. The subjects' mean score of depression was 17.36(6.77), and their scores of acculturation stress, academic stress, and career stress were 69.51(19.06), 34.64(5.03), and 29.13(9.14), respectively. Acculturative stress and career stress were found to be factors influencing the depression level of Chinese students in Korea and the two factors' explanatory power was 51.9%. Based on the findings of this study, in order to lower Chinese students' depression level and help them lead a healthy academic life in Korea, it is necessary to assess their acculturative stress and career stress and to provide special intervention for students with high perceived stress.

• Structural Engineering and Mechanics
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• v.30 no.3
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• pp.317-330
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• 2008

Stress intensity factors for a planar crack parallel to a bimaterial interface are considered. The formulation leads to a system of hypersingular integral equations whose unknowns are three modes of crack opening displacements. In the numerical analysis, the unknown displacement discontinuities are approximated by the products of the fundamental density functions and polynomials. The numerical results show that the present method yields smooth variations of stress intensity factors along the crack front accurately. The mixed mode stress intensity factors are indicated in tables and figures with varying the shape of crack, distance from the interface, and elastic constants. It is found that the maximum stress intensity factors normalized by root area are always insensitive to the crack aspect ratio. They are given in a form of formula useful for engineering applications.

• Proceedings of the KSME Conference
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• 2000.04a
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• pp.176-181
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• 2000

Stress intensity factors for a rigid line inclusion tying along a bimaterial interface are calculated by the boundary element method with the multiregion and double-Point techniques. The formula between the stress intensity factors and the inclusion surface stresses are derived. The numerical values of the stress intensity factors for the bimaterial interface rigid line inclusion in the infinite body are proved to be in good agreement within 3% when compared with the previous exact solutions. In the finite bimaterial systems, the stress intensity factors for the center and edge rigid line inclusions at interface are computed with the variation of the rigid line inclusion length and the shear modulus ratio under the biaxial and uniaxial loading conditions.

• Proceedings of the Safety Management and Science Conference
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• 2008.11a
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• pp.329-341
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• 2008

The psychosocial stress and musculoskeletal disorders(MSDs) have been one of major health problems for hospital workers. This study tried to understand the relationship between symptoms associated with MSDs and risk factors such as working posture, job stress, psychosocial stress and fatigue. A total number of 655 hospital workers participated in this study. Specifically, REBA was applied for evaluating working posture and a checklist prepared by KOSHA(Korean Occupational Safety and Health Agency) was used for symptom survey. A questionnaire from KOSHA was also used for collecting data associated with job stress, psychosocial stress and fatigue. All these data were formulated and modeled by path analysis which was one of major statistical tools in this study. Specifically, path analysis for the data we collected came up with several major findings. The risk scores from working posture based on REBA had indirect effects via fatigue factor(MFS) as well as direct effects on symptoms. The factors associated with job stress(KOSS) and psychosocial stress(PWI-SF) had significant effects on symptoms. Specifically, indirect effect of job stress factors via fatigue factors(MFS) had bigger than that of direct effect of job stress on symptom.

• Journal of Families and Better Life
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• v.25 no.5
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• pp.107-126
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• 2007

This study explored the buffering effect of family resilience between family stress and adjustment of single parent family based on family resilience approach. Results of the study were as followed: First, single parents who had a lower level of family stress and a higher lever of family resilience reported a higher level of family adjustment. Second, family stress especially economic stress and relational stress influenced negatively on adjustment of single parent family. Family belief system, organizational pattern and communication processes of the three sub-factors of family resilience influenced positively on family adjustment. However the sub-factors of family resilience had more powerful effects than family stress. Third, family belief system, organizational pattern and communication processes of the three sub-factors of family resilience had a moderating effect between family adjustment and psychological stress and between family adjustment and relational stress. Especially the three sub-factors of family resilience had a buffering effect between family adjustment and relational stress. The results of this study had important implication for theory, research, and practice. The study showed that adjustment of single parent family could be significantly explained by family resilience rather than family stress. Accordingly strength perspective-based intervention focused on family resilience would be more effective than deficit perspective-based intervention based on family stress.

• Journal of The Korean Society of Integrative Medicine
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• v.5 no.3
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• pp.39-47
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• 2017

Purpose : This study was conducted to analyze the job stress factors affecting the job satisfaction and job involvement of physical therapists and to provide basic information for the prevention of job stress among physical therapists. Method : One hundred and eighty-four physical therapists working in hospitals participated in the study by completing the Korean Occupational Stress Scale and surveys about job satisfaction and job involvement. The results were collected and analyzed. Result : The job stress factors the significantly influenced job satisfaction are the following, in order of importance: the organizational climate (p<.05), inter-personal conflict (p<.01), insufficient job control (p<.001), lack of reward (p<.001), and the occupational system (p<.001). The following factors significantly influenced job involvement, again in order of importance: job demand (p<.001), the organizational climate (p<.05), lack of reward (p<.05), the occupational system (p<.01), and insufficient job control (p<.001). Conclusion : The purpose of this study was to analyze the job stress factors affecting the job satisfaction and job involvement of physical therapists and to provide basic information to prevent job stress among physical therapists. The results indicate the need for more studies that analyze the job stress factors of physical therapists and additional studies that specifically analyze the tasks of physical therapists. Studies on how to reduce job stress among physical therapists must also be conducted in the future.

• Journal of the Korean Society of School Health
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• v.31 no.3
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• pp.186-195
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• 2018

Purpose: This study was performed to investigate the dietary behaviors and stress-related factors among male and female college students. Methods: A total of 405 college students (male-195, female-210) were recruited, of whom a questionnaire-based survey was conducted. The study investigated the general characteristics, health-related factors, dietary behaviors, and stress-related factors of the respondents. Results: The body mass index was significantly higher in males. The rates of underweight and overweight were significantly different between male and female respondents. The scores for workout frequency, health concerns and health condition were significantly higher in males, while the score for watching TV & playing computer games was significantly higher in females. The scores for meal regularity, frequency of breakfast consumption, and smoking were significantly higher in males. Eating problems showed a significant difference between males and females. The biggest source of stress was social factors, followed by college study and individual factors and the most experienced stress-induced symptom was anxiety, followed by headache and stomachache. The most popular way to overcome stress was taking a rest, followed by drinking & smoking and outdoor activity. The most preferred food under stressful conditions were alcohol or beverages, followed by hot & spicy food and sweet food, which showed a significant difference between males and females. Conclusion: These results indicate that stress affects dietary behaviors, drinking, smoking, and health status. Stress not only changes dietary behaviors, but is also related to health status. Therefore, it is necessary to develop appropriate programs for emotional stability and stress relief targeting college students which provide continuous nutrition education focused on desirable dietary behaviors and nutritional aspects.

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.1
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• pp.119-129
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• 1990

In case that the body with a cusp crack is under uniform heat flow, thermal stress intensity factors are calculated by using boundary element method with linearized body force term. The crack surface is under insulated or fixed temperature condition and the types of crack are symmetric lip and airfoil cusps. Numerical values of thermal stress intensity factors for a Griffith crack and cusp cracks in infinite bodies are proved to be in good agreement within .+-.5% when compared with the previous numerical and exact solutions, respectively. The thermal stress intensity factors for symmetric lip and airfoil cusp cracks in finite bodies are calculated about various effective crack lengths, configuration parameters, and heat flow directions. With the same crack surface thermal boundary conditions, heat flow directions and crack lengths, there are no appreciable differences in variations of thermal stress intensity factors between symmetric lip and airfoil cusp cracks. The signs of thermal stress intensity factors for each cusp crack are changed with each crack surface thermal boundary condition.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.7
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• pp.1255-1265
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• 1992

Under uniform heat flow, the thermal stress intensity factors for the interfacial crack on a rigid cusp-type inclusion are determined by Hilbert problem expressed with complex variable. The thermal stress intensity factors are expressed in terms of the periodic function of heat flow angle. When the tip of the interfacial crack meets that of the cusp crack, the thermal stress intensity factors have singularities. The thermal stress intensity factors at the interfacial crack tip located in the distance from the cusp crack tip vary with the location of the interfacial crack tip. From the results of the analysis, the complex potential functions and the thermal stress intensity factors for the cusp-type inclusion without the interfacial crack are derived under the cusp surface boundary conditions insulated or fixed to zero relative temperature.