• Geomechanics and Engineering
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• v.31 no.1
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• pp.87-97
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• 2022

The excessive settlement and deformation of disintegrated carbonaceous mudstone (DCM) embankments under dynamic loading have long been problems for engineers and technicians. In this work, the characteristics and mechanism of the plastic deformation of DCM under different degrees of compaction, water contents and confining pressures were studied by static triaxial, dynamic triaxial and scanning electron microscopy testing. The research results show that the axial stress increases with increasing confining pressure and degree of compaction and decreases with increasing water content when DCM failure. The axial strain at failure of the DCM decreases with increasing confining pressure and degree of compaction and increases with increasing water content. Under cyclic dynamic stress, the change in the axial stress level of the DCM can be divided into four stages: the stable stage, transition stage, safety reserve stage and unstable stage, respectively. The effects of compaction, water content and confining pressure on the critical axial stress level which means shakedown of the DCM are similar. However, an increase in confining pressure reduces the effects of compaction and water content on the critical axial stress level. The main deformation of DCM is fatigue cracking. Based on the allowable critical axial stress, a method for embankment deformation control was proposed. This method can determine the degree of compaction and fill range of the embankment fill material according to the equilibrium moisture content of the DCM embankment.

• Journal of Korean Academy of Nursing
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• v.35 no.6
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• pp.1183-1189
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• 2005

Objectives : This descriptive study was conducted to examine the degree of stress, coping styles, communication with the mother and depression between headache-suffering children and headache-free children and to explore predicted factors for headache occurrence in children. Method : The subjects of this study consisted of 196 headache-free children and 107 headache-suffering children. They were 4th-6th graders of an elementary school in T city. The instruments in this study were David's stressor of children, Lazarus & Folkman's Stress Coping Style, PACI(Parent-Adolescent Communication Inventory) by Barnes & Olsen and Kovac's CDI (Children's depression inventory). Data were collected from May 2 to July 16, 2004. Results : Total stress(t=-3.76, p=.035), school stress(t=-3.02, p=.001), mass media stress(t=-1.39, p=.029) and depression(t=7.62, p=.001) in headache-suffering children were significantly higher than those of headache-free children. Problem-oriented coping skills (t=1.23, p=.023), and the score of communication with the mother(t=2.32, p=.012) in headache-suffering children were lower than those of headache-free children. Logistic regression analysis (stepwise) showed that the most powerful predictor was stressors in school, followed by depression, stressors in mass media and communication with the mother. Conclusions: This study revealed that important factors such as the degree of school stress, depression, the degree of mass media stress, communication with the mother and problem-oriented coping skills should be controlled for reducing of headaches in children.

• Journal of Korean Academy of Nursing
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• v.25 no.1
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• pp.110-123
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• 1995

This study was done to analyze the relationship between task stress and morale in psychiatric nursing assistants. The subjects were 118 psychiatric nursing assistants selected from the National Mental Hospital in Seoul and 18 non-medical mental institutions. The data were collected from October 22 to November 12, 1994. The instruments used for this study were modified PNOSS (Psychiatric Nurse Occupational Stress Scale) which was developed by Bai and modified the Morale scale which was developed by Oh. The confidence varification of these instruments were computed and Cronbach $\alpha$=.9255, .9260. Data were analyzed by t -test, ANOVA on 5% significant level and Pearson correlation coefficient. The results of the study are as follows : 1. The average work stress scores of subjects were 2.83. Among the work stress factors : the conflict with nurse was identified as the most stress factor. There was significant relationship between the degree of work stress and the variables of psychiatric Nursing Assistants such as the marital status, educational level, religion, job satisfaction, working place, predicted period of work. 2. Average total morale scores for the subjects was 3.08. There was a significant relationship between the degree of morale and variables of psychiatric nursing assistants such as working place, certification as a nursing assistant, job satisfaction, opportunity for practical education and predicted period of work. 3. There was a significant relationship between the degree of morale and work stress factors such as administration problem, work overload.

• Journal of Technologic Dentistry
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• v.23 no.2
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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.

• The Journal of Korean Physical Therapy
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• v.2 no.1
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• pp.65-74
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• 1990

This study was carried out to measure the degree of work-related stress and to identify factors influencing the excessive stress among clinical physical therapists. One thousand and five physical therapists surveyed nationwide met the established criteria for inclusion in the study. The respondents were an average age of 27.1 years, $34.5\%$ were married, and $61.2\%$ were female. Most of the respondent $(48.1\%)$ worked in local clinics. The average stress score was 50.9. Analysis-of-variance test demonstrated significant difference in the degree of stress among treatment facilities. There was a significant relationship between treatment facilities (general hospital, local hospital, clinic), number of patients treated per day, job satisfaction, low back pain and work-related stress, respectively. Work-related stress was unrelated to matters of sex, marital status, education. Hospital administrators, physical therapydirectors, directors, and individual therapists should work within their organizations to reduce work stress and its detrimental effects. Further research is necessary to investigate preventive measures to decrease the work-related stress.

• Korean Journal of Health Education and Promotion
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• v.19 no.2
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• pp.45-55
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• 2002

This study was conducted to evaluate the degree of stress state and stress related factors in 280 male white collar workers by using Psychosocial Well-being Index. The results were as follows; 1. According to Psychosocial Well-being Index, mild stress state was 78.6 %, healthy state was 12.9 %, and high risk stress state was 8.6 %. Single marital status, low education level, low income and low frequency of exercise group had high score of stress. 2. The total stress score was highly associated with the factors of social performance and self confidence, depression, general well-being and vitality, and sleeping disturbance and anxiety in order. 3. In reliability test of stress factors, Cronbach's a coefficients of social performance and self confidence, sleeping disturbance and anxiety, depression, general well-being and vitality were 0.91, 0.91, 0.90, and 0.89 respectively. In conclusion, it suggested that marital status, income, education, and exercise were associated with stress score. All of the above factors should be considered to white collar workers health.

• Computers and Concrete
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• v.25 no.2
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• pp.145-154
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• 2020

For the influence of the propagation law of stress wave at the coal-rock interface during the pre-blasting of the top coal in top coal mining, the ANSYS-LS/DYNA fluid-solid coupling algorithm was used to numerical calculation and the life-death element method was used to simulate the propagation of explosion cracks. The equation of the crushing zone and the fracturing zone were derived. The results were calculated and showed that the crushing radius is 14.6 cm and the fracturing radius is 35.8 cm. With the increase of the angles between the borehole and the coal-rock interface, the vibration velocity of the coal particles and the rock particles at the interface decreases gradually, and the transmission coefficient of the stress wave from the coal mass into the rock mass decreases gradually. When the angle between the borehole and the coal-rock interface is 0°, the overall crushing degree is about 11% and up to the largest. With the increase of the distance from the charge to the coal-rock interface, the stress wave transmission coefficient and the crushing degree of the coal-rock are gradually decreased. At the distance of 50 cm, the crushing degree of the coal-rock reached the maximum of approximately 12.3%.

• Journal of Dental Rehabilitation and Applied Science
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• v.17 no.4
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• pp.283-305
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• 2001

The purpose of this study was to analyze the stress distribution of condylar regions and edentulous mandible with implant-supported cantilever prostheses on the certain conditions, such as amount of load, location of load, direction of load, fixation or non-fixation on the condylar regions. Three dimensional finite element analysis was used for this study. FEM model was created by using commercial software, ANSYS(Swanson, Inc., U.S.A.). Fixed model which was fixed on the condylar regions was modeled with 74323 elements and 15387 nodes and spring model which was sprung on the condylar regions was modeled with 75020 elements and 15887 nodes. Six Br${\aa}$nemark implants with 3.75 mm diameter and 13 mm length were incorporated in the models. The placement was 4.4 mm from the midline for the first implant; the other two in each quardrant were 6.5 mm apart. The stress distribution on each model through the designed mandible was evaluated under 500N vertical load, 250N horizontal load linguobuccally, buccal 20 degree 250N oblique load and buccal 45 degree 250N oblique load. The load points were at 0 mm, 10 mm, 20 mm along the cantilever prostheses from the center of the distal fixture. The results were as follows; 1. The stress distribution of condylar regions between two models showed conspicuous differences. Fixed model showed conspicuous stress concentration on the condylar regions than spring model under vertical load only. On the other hand, spring model showed conspicuous stress concentration on the condylar regions than fixed model under 250N horizontal load linguobuccally, buccal 20 degree 250N oblique load and buccal 45 degree 250N oblique load. 2. Fixed model showed stress concentration on the posterior and mesial side of working and balancing condylar necks but spring model showed stress concentration on the posterior and mesial side of working condylar neck and the posterior and lateral side of balancing condylar neck under vertical load. 3. Fixed model showed stress concentration on the posterior and lateral side of working condylar neck and the anterior and mesial side of balancing condylar neck but spring model showed stress concentration on the anterior sides of working and balancing condylar necks under horizontal load linguobuccally. 4. Fixed model showed stress concentration on the posterior side of working condylar neck and the posterior and lateral side of balancing condylar neck but spring model showed stress concentration on the anterior side of working condylar neck and the anterior and lateral side of balancing condylar neck under buccal 20 degree oblique load. 5. Fixed model showed stress concentration on the anterior and lateral side of working condylar neck and the posterior and mesial side of balancing condylar neck but spring model showed stress concentration on the anterior side of working condylar neck and the anterior and lateral side of balancing condylar neck under buccal 45 degree oblique load.. 6. The stress distribution of bone around implants between two models revealed difference slightly. In general, magnitude of Von Mises stress was the greatest at the bone around the most distal implant and the progressive decrease more and more mesially. Under vertical load, the stress values were similar between implant neck and superstructure vertically, besides the greatest on the distal side horizontally. 7. Under horizontal load linguobuccally, buccal 20 degree oblique load and buccal 45 degree oblique load, the stress values were the greatest on the implant neck vertically, and great on the labial and lingual sides horizontally. After all, it was considered that spring model was an indispensable condition for the comprehension of the stress distributions of condylar regions.

• Journal of agricultural medicine and community health
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• v.25 no.1
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• pp.51-63
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• 2000

Ten Dongs were selected according to the systematic cluster sampling in Koryong Gun, and the survey was conducted on 571 women in the age between 30-69 years. The first survey was performed for 6 days between August 27 to September 1, 1999 with the investigation rate of 60.3%, and the second survey was performed in November with the investigation rate of 91.8%. The contents of survey included demographic characteristics, health behaviors, dyspepsia symptom score, sleeping induction time and the degree of sleep satisfaction, and degree of stress in the subjects. The dyspepsia symptom score was in the average 13.4 points out of a total 44 points and was the highest in the 50-59 year-old age group with 13.9 points. The sleep induction time was in the average of 35 minutes and was the highest in the 50-59 year-old age group with 40.9 minutes; the degree of sleep satisfaction was in the average of 7.9 points and was the lowest in the 50-59 year-old age group with 7.5 points. The stress score was in the average of 18.3 points and was highest in those subjects in their 40's and 50's with 18.7 points. When the correlation among the stress score, the degree of sleep satisfaction and dyspepsia symptom score was analyzed, the results showed that he stress score and the degree of sleep satisfaction showed a significant negative correlation and that the stress score and dyspepsia symptom score showed a significant positive correlation. Also, a significant negative correlation was found between the degree of sleep satisfaction and dyspepsia symptom score. According to each age group, a significant correlation was revealed among the stress score, dyspepsia symptom score and the degree of sleep satisfaction in those subjects over 40 years of age compared to those subjects who were younger than 40 years of age. As for educational level, the correlation among the stress score, the degree of sleep satisfaction and dyspepsia symptom score was higher in those subjects with less than middle school education compared to those subjects with more than high school education. When those factors that effects on the dyspepsia symptom score were analyzed with multiple regression, the results showed that the level of stress and chronic diseases were selected as significant variables. When those factors that affected on the degree of sleep satisfaction were analyzed, the sleep induction time and presence of chronic diseases and stress were selected as significant variables. Those women in their 50's who live in rural areas showed the highest level of stress, lowest the degree of sleep satisfaction, and highest level of dyspepsia, indicating that they need stress management. Also, since stress was showed to be a significant variable effecting on dyspepsia or the degree of sleep satisfaction, it is concluded that health promotion is possible through stress management. More studies are needed in the future on coping resources that would strengthen coping against stress, and by conducting studies on stress and related factors on community people, the measures of mental health promotion need to be developed.

• Journal of Korean Academy of Nursing Administration
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• v.5 no.1
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• pp.169-180
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• 1999

The purpose of this study was to identify the degree of stress and job satisfaction and the relationship of stress and job satisfaction of oriental hospital nurses. The subjects were 255 nurses of 9 oriental hospital in Taegu and Pusan cities and data were collected from 20 March to 10 May 1998. The instruments used for this study were a survey of genernal characteristics(7 items). stress(6 items) and job satisfaction(20 items). Analysis of data was done by use of mean, percentage, t-test, ANOVA and pearson correlation with SPSS program. The results of this study are as follows : 1) The average item score for stress was 3.08. Religion, duration of nurse expectancy and work motivation among sociodemographic characteristics were significantly different with the degree of stress. 2) The average item score for job satisfaction was 2.84. Education, religion, marital state, carrier history, duration of nurse expectancy and work motivation among sociodemographic characteristics were significantly different with the degree of job satisfaction. 3) There were significant negative correlation among the variables : working volume and group conflict factors · role implementation fators${\cdot}$personal socialization fators/nursing skill and role implementation fatal's· personal socialization fators/rolesharing with peers and role implementation fators/relationship with co-workers and group conflict factors${\cdot}$role implementation fators${\cdot}$personal socialization fators/relationship with patients and role implementation fators/relationship with supervisors and role implementation fators. And there was a significant positive correlation between role-sharing with peers and decision-making fators.