• 한국자동차공학회논문집
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• 제6권4호
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• pp.121-128
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• 1998

In this study, when tension and bending stress act on plate simultaneously, stress intensity factor is analyzed at crack tip with using BEM(Boundary Element Method). In this analysis, stress intensity factors(S.I.F) are defined for variable ligament, aspect and stress ratio($\sigma$T/$\sigma$B). Consequently, predicted that crack grow to depth direction at low aspect and ligament ratio in tension stress and to surface direction in bending stress. Tension and bending stress act on plate same time, effect of tension stress in the first stage and effect of bending stress in the after stage was to observed. The outbreak of secondary crack in backside is under the control of stress amplitude and predict that the point of outbreak is mear backside.

• 한국자동차공학회논문집
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• 제13권2호
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• pp.142-148
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• 2005

In this paper, the stress singularity on interface of friction welded dissimilar materials was investigated by using 2-dimensional elastic boundary element method. It is required that stress distributions and stress singularities on an interface for friction welded dissimilar materials analize to establish strength evaluation. The stress singularity index ($\lambda$) and stress singularity factor ($\Gamma$) were calculated from the results of stress analysis. The stress singularities on variations for shapes and thickness of friction welded flashes were analized and discussed. This paper suggested that the strength evalution by using the stress singularity factors as fracture parameters, considering the stress singularity on an interface edge of friction welded dissimilar materials were very useful.

• 한국농공학회지
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• 제45권2호
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• pp.86-95
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• 2003

During this study, constant stress ratio tests with previous compression anisotropic stress history are performed on compacted decomposed granite soil sampled at Iksan, Jeonbuk. Yielding points are determined from stress-strain curves. The shape and characteristics of compression anisotropic yield curves is examined. In addition, the measured value of yielding curve and stress-strain behavior is predicted by Yasufuku's anisotropic constitutive model based on non-associated flow rule. The main results are summarized as follows : 1) Shape of yielding curves shows almost ellipse but asymmetry with respect to stress path during previous consolidation stress. 2) Yasufuku's anisotropic constitutive model is suitable in evaluation of yielding curves on anisotropic consolidated decomposed granite soil. 3) The predicted stress-strain curve shows reasonable agreement to measured behaviours.

• 산업경영시스템학회지
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• 제26권1호
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• pp.40-46
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• 2003

The employees in information system organization are highly exposed to stress. However, there is little theoretical or empirical study on the effects of job stress on IS organizations. A major reason is because few researchers consider consequences of job stress. The major purpose of this study is to verify negative effects of job stress for IS organization. This study have three purposes : to investigate the relationship between job stressors and perceived job stress; to understand the effect of perceived job stress and job attitude - job satisfaction, job involvement; to examine the role of moderators such as social support and personality in the relationship between job stressors and perceived job stress in information system organizations. The results of this study suggest that job stressors such as role overload and role ambiguity are significantly related to perceived job stress, the higher the perceived job stress is the lower the job attitudes such as job satisfaction and job involvement, and the employees' personality has moderating effects between the job stressor and perceived job stress.

• 반도체디스플레이기술학회지
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• 제3권2호
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• pp.35-40
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• 2004

The total relaxed stress in annealing and the thermal strain/stress were obtained from the identification of the residual stress-free state using electronic speckle pattern interferometry (ESPI). The residual stress fields in case of both single and film / substrate systems were modeled using the thermo-elastic theory and the relationship between relaxed stresses and displacements. We mapped the surface residual stress fields on the indented bulk Cu and the 0.5 $\mu\textrm{m}$ Au film by ESPI. In indented Cu, the normal and shear residual stress are distributed over -1.7 GPa to 700 MPa and -800 GPa to 600 MPa respectively around the indented point and in deposited Au film on Si wafer, the tensile residual stress is uniformly distributed on the Au film from 500 MPa to 800 MPa. Also we measured the residual stress by the x-ray diffractometer (XRD) for the verification of above residual stress results by ESPI...

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2001년도 봄 학술발표회 논문집
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• pp.365-372
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• 2001

This study is concerned with the application of an analytical model of cyclic crack growth that includes the effects of crack closure. The crack closure model is based on the Dugdale model and the strip model, considering the plasticity-induced closure which is caused by residual plastic deformation remaining in the wake of an advancing crack. This study is performed to get the relation between crack growth and crack opening stress with the constant stress ratio, and the relation between stress ratio and crack opening stress with the constant maximum stress under constant-amplitude loading. Under constant-amplitude loading, the crack opening stress is conversed the constant value as a crack grows and is proportion to both the stress ratio and the maximum stress. The crack closure effect, however, is decreased in the positive stress ratio and disappeared at about 0.7. The crack growth analysis using the crack closure model shows that the influence of stress ratio is minimized in the relation between crack growth ratio and effective stress intensity range specially at the negative stress ratio.

• 대한간호학회지
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• 제28권2호
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• pp.358-368
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• 1998

This was designed to identify the relationship of perceived stress, ways of coping, and stress response in student nurses. The subjects of this study were 320 student nurses from two universities and three junior colleges located in Seoul. The data were collected from November 28 to December 10, 1997 by a questionnaire survey method. The instruments for this study were the perceived stress scale developed by Levenstein(1993), ways of coping scale developed by lazarus & Folkman (1984), and the stress response scale developed by Choi(1991). The data were analyzed by SAS program, using descriptive statistics, Pearson correlation coefficient, and ANOVA. The results are summarized as follows : 1. The mean score for the level of perceived stress was 2.55. 2. The mean score for the level of problem oriented coping was 1.61 and the mean score for the level of emotional oriented coping was 1.37. 3. The mean score for the level of stress response was 3.74. Stress was classified into nine factors and the order of scoring for the most frequent was ; assignments(3.98), as a nurse(3.97), interpersonal relationship(3.88). 4. The relationship between perceived stress and stress response revealed a positive significant correlation(r=0.23, p=0.0001) 5. The relationship between emotional oriented coping and stress response revealed a positive significant correlation(r=0.22, p=0.0001). 6. The relationship between perceived stress and emotional oriented coping revealed a positive significant correlation(r=0.13, p=0.020). In conclusion, this study revealed that the level of perceived stress and ways of coping were important factors influencing the stress response of student nurses. Therefore, in consideration of perceived stress, ways of coping should be included in the development of a stress management program for student nurses. Further research with an expanded area and subjects is recommended.

• 대한치과기공학회지
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• 제23권2호
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• pp.105-119
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• 2002

This study was designed to grasp the degree of job stress affecting dental technicians and the degree of the symptoms of their job stress. With this in mind, the researcher selected a total of 170 dental technicians living in Seoul and Incheon, conducting a research in a period ranging from August 1,2001, to August 20, 2001. The researcher made use of a structured questionnaire whose reliability and feasibility are proved. The questionnaire is composed of a total of 55 questions: thirteen questions related to the subjects' general characteristics; 28 questions connected to the measurement of job stress and fourteen questions linked with the measurement of job-stress symptoms. The researcher analyzed the findings with the aid of SPSS(Statistical Package for Social Sciences). The research came to draw the following conclusions on the basis of frequency, percentage, T-test, and F-test, multiple regression. I. The analysis into the job stress of the subjects indicates that there is a significant difference in difficult questions among their work places, working hours, academic background, job satisfaction and jobs(P<.05). The job stress stands at 3.48 on the average, and the area of conflict among too much work and job performance turns out to be highly perceived. 2. The analysis into the degree of the symptoms of the job stress of the subjects shows that there is a significant difference in work place, working hours, job satisfaction and the continual maintenance of job(P<.05). The symptoms of job stress accounts for 2.65 on the average. Physical symptoms turn out to be highly perceived; The response 'My arms and legs are killing me' proves to stand for 3.03. 3. The correlation between job stress and the symptoms of job stress turns out to be significant(r=0.519, P<0.001), and there is a significant correlation between the average points of each job-stress area and the average points of the symptoms of job stress. All in all, it is necessary that dental technicians themselves should make positive efforts to control and relieve stress and that more efficient programs should be implemented with a view to dealing with stress.

• 대한간호학회지
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• 제29권6호
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• pp.1392-1402
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• 1999

This study was carried out to find out stress-eating relationship in obese high school girls and to investigate the factors related to stress-induced eating. The conceptual framework used in this study was individual difference model. The research method was methodological triangulation. The data of the study were collected from purposively sampled 309 normal high school girls and 314 obese high school girls in S city. 15 volunteers, obese high school girls, enrolled in this qualitative research. Quantitative data was collected from May 6 to June 10, 1997 through questionnaires about stress and stress-related eating changes and from June 23 to August 26, 1997, qualitative data was collected. The results of the study were as follows : 1. Obese high school girls were unaffected by stress(t=-1.84, p=0.0662). 2. Through quantitative analysis, obese people divided into two groups in their response to stress. One group was composed of stress- eater. The other group was composed of non- stress eater. 3. Disinhibition(t=-3.1275, p=0.0019), cognitive restrain (t=-3.1597, p=0.0017), hunger(t=-3.5878, p=0.0004) were significantly different between stress-eaters and non-stress eaters. 4. According to the interview, 5 subjects of obese girls were stress eaters, and 10 subjects were non-stress eaters. Through qualitative research, the related factors of eating were eating attitude & behavior, stimuli situations on eating, and personality. In stress-eater group, they constantly went on a diet, however, they were prompted to eat when an uneasy feeling such as anxiety, depression, annoyance developed. Their personality were entirely optimistic. Whereas non-stress eater group had no interest in diet and didn't appear to have psychological factors to stimulate eating in stressful situations. Their personality was not only optimistic but also keenly characteristic. 5. To compare obese-normal high school girls on the effect of stress in eating. Normal weigh high school girls decreased their eating when stressed(t= -13.62, p=0.0001). In conclusion, this study suggests that there are two different groups in obese high school girls in regards to eating responses on stressful situations. As a result of these finding, clinical and school nurses can detect the stress-eaters who need stress management intervention, and can apply appropriate management program according to the individual needs.

• 대한간호학회지
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• 제27권2호
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• pp.289-302
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• 1997

The main purpose of this study was to identify the effects of integrated stress management program on the stress symptoms of psychophysiological patients. especially patients with peptic ulcer. The study employed a quasi-experimental design using two different experimental groups. The samples in the integrated stress management program participated in autogenic training with biofeedback. discussions on effective coping method. cognitive. behavioral, and emotional management. They were also provided with an educational booklet on stress management and an tape on progressive muscie relaxation. Each session lasted one hour and the program consisted of seven sessions over four weeks. The other group was only given an tape on progressive muscle relaxation. The data were collected from May 20 to september 25, 1996. A total 47 patients from one university hospital located in Seoul participated, experiment group 1(integrated stress management training) had 23 subjects and experiment group 2(progressive muscle relaxation training) had 24 subjects. The effects of these programs were measured by the stress symptom scale developed by Kogan(1991) which was translated by Lee(1992) and the healing status of the ulcer evaluated by a physician. The data were analyzed using Chi-square test, t- test, ANOVA, repeated measure ANOVA. The result are as follows : 1. The integrated stress management group reported a significantly lower stress symptom score than the group given the progressive muscle relaxation only. 2. The integrated stress management group showed a significantly improved ulcer status as compared to the group given a progressive muscle relaxation only. In conclusion, it was found that the integrated stress management program was more effective in decreasing self-reported stress and physiological symptoms among patients with peptic ulcer as compared to the progressive muscle relaxation group. Based on this finding, the following suggestions can be made. 1. It is necessary to broaden the scope of nursing practice for psychophysiological patients so nurses can include stress management as part of patient care. 2. It is necessary to develop stress management program for other patients whose symptoms are known to be related to stress. 3. It is necessary to replicated this study with a larger sample in different settings.