• Transactions of the Korean Society of Mechanical Engineers
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• v.6 no.2
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• pp.107-112
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• 1982

In order to analyze and investigate in the fatigue behavior of the notched specimens under the two level stressing, the U-notched specimens of structural carbon steel which is generally used is prepared. The obtained results are summarized as follows; (1) The fatigue limit of the U-notched specimens is lower than that of the unnotched. The fatifue notch factor (.betha.) of the U-notched specimens is 1.44 for mild steel and 1.52 for harden steel. The notch sensitivity (q) is 0.68 for mild steel and o.8 for harden steel. That is, these facts show that harden steel is more sensitive to the notch than mild steel. (2) The fatigue life time of the U-notched specimens under the overstressing is shorter than under the constant stressing, and the degree of fatigue life time decrease is different to each stress level; the degree for the high stress level is more than for the low stress level. (3) The fatigue life time of the U-notched specimes under the understressing is longer than under the constant stressing, and the degree of fatigue life time increase for the low stress level is more than for the high stress level.

• Child Health Nursing Research
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• v.9 no.1
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• pp.36-45
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• 2003

The purpose of this study was to explore the various aspects of the fatigue in the mothers of infants and toddlers in descriptive study. Three hundred eighty mothers who visited the public primary health care center in subrural area were enrolled from October, 2001 to June, 2002. Data were collected using a questionnaire titled 'Symptom Table on Fatigue Perception' designed by the Fatigue Research Committee of Japan, consisted of a total 30 items categorized into three subdimensions: the physical, the psychological and the neuro-sensory. SPSS was used for the analysis of data with 0.05 of significance. The results were as follows: 1. The mean average fatigue score of subjects was 1.81(SD:.41): the physical fatigue revealed the highest value with a mean of 1.92(SD:.50), followed by psychological fatigue with a mean score of 1.79(SD:.48), neuro- sensory fatigue with a mean of 1.72(SD:.44). 2. With the respect to the general characteristics of subjects, there were statistically significant differences in the mothers' fatigue perception by with or without a job or not(t=2.213, p=.028), the number of children(t=-2.157, p=.032), the degree of spouse support in domestic households(F=3.315, p=.045), the degree of spouse support in the care of children(F=12.616, p=.000), and the amount of sleeping time(t=.130, p=.000). These results suggest that health care professional need to be aware of the persistent presence of the maternal fatigue related to the child rearing and the factors worsen the degree of the fatigue.

• Journal of Industrial Technology
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• v.20 no.A
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• pp.149-158
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• 2000

After measuring actual stress by two measurements(Dynamic Strain Meter, Histogram Recorder) on truss rail road bridge, we could perform time history analysis by 3-D beam element method on modelling bridge. And then, after analyzing bridge structure in static by 3-D modelling, we estimated degree of fatigue damage in main member, secondary member of tie zone, cutting area of base metal cross section for confirming the result. In case that the simulated stress is carried out on modeling bridge, most of those simulation mainly is performed by main members. But in real bridge fatigue damage problems generally caused by junctions, connections, joints in which especially local stress is activated. Therefore, in this paper actual stress on critical area was estimated through the analysis result by simulation. With this study, we can estimate the degree of fatigue damage from a safety point of view and comparative accuracy.

• Journal of the Korea institute for structural maintenance and inspection
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• v.7 no.1
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• pp.199-206
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• 2003

This paper presents the fatigue life of transverse joint of concrete pavement with the fatigue model test. A 1/12 scale model was used to satisfy the geometric load, material similitude, which are variables to the skew angel of transverse joint. From the test results by fatigue load 700kgf applied, we can have that the fatigue life of transverse joint with skew angle is better than that of transverse joint without skew angle. In addition, we can have that the fatigue life of skewed transverse joint with angle of 10 degree is better than that of skewed transverse joint with angle of 20 degree.

• The Korean Journal of Emergency Medical Services
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• v.8 no.1
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• pp.71-86
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• 2004

This study selected emergency medical technicians at 24 fire police boxes in Jeonnam in order to examine the relationship between job stress, fatigue and job satisfaction of 119 emergency medical technicians. Data were collected from Apr. 10 to May 9, 2004, questionnaires were mailed and returned by mail. Total 109 questionnaires were distributed and 89 questionnaires were collected and 80 except 9 omitting answers and showing inappropriate answers were used for final analysis. The results of this study are as follows. A. The total mean of areas composing job stress in the degree of job stress of 119 emergency medical technicians was over the average as 2.54 (SD .44) of 4 full marks. According to the degree of job stress by each area, the highest area of job stress was crisis situation (2.98), followed by role conflict as professional job (2.58), social factors (2.57), involvement in organization (2.55). To the contrary, the areas of the lowest job stress were professional knowledge and technique (2.35), psychological burden of medical limitation (2.38), conflicts in personal relationship and services (2.45) and improper treatment (2.53). B. The degree of fatigue of 119 emergency medical technicians by areas was over mean as 2.09(SD .49) of 4 full scores and physical fatigue was highest (2.18), followed by mental fatigue (2.11) and neurosensory fatigue (1.99). C. The degree of job satisfaction of 119 emergency medical technicians was 2.71 of 5 full scores and working condition area (3.70) showed the highest job satisfaction, followed by requirement of organization (2.85) and the lowest job satisfaction area was job itself (2.18), followed by desire for job (2.49). D. According to differences in demographical characteristics of 119 emergency medical technicians, there was no variable of statistical difference at job stress and job satisfaction in significance level .05, but fatigue showed statistical difference at final education (F=2.393, p=.046). E. According to differences related to job characteristics of 119 emergency medical technicians, job stress showed statistical differences at motif of current services (F=4.935, p=.003), fatigue showed those at health conditions (F=2.732, p=.008), job satisfaction at overtime (F=3.038, p.034) and the greatest reason of having job (F=3.217, p=.017), F. As a result of analyzing correlations between job stress. fatigue and job satisfaction of the subject, job stress showed positive correlations (r=.411, p=.000) with fatigue and negative correlation (r=-.267, p=.008) with job satisfaction. Fatigue showed negative correlation (r=-.287, p=.005) with job satisfaction. Therefore, the hypothesis of this study. "There will be relationship between degree of stress, fatigue and job satisfaction of subjects." was supported.

• Journal of muscle and joint health
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• v.14 no.1
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• pp.61-69
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• 2007

Purpose: The purpose of the study is to investigate the degree of fatigue and its related factors in women with rheumatoid arthritis. Method: The subjects were 143 patients with rheumatoid arthritis. Data were collected by questionnaires including Multi-Dimensional Assessment of Fatigue(Tack, 1991), Korean Health Assessment Questionnaire(Bae et al., 1991), numeric scale of pain(Lee & Song, 1987), Center for Epidemiologic StudiesDepression, and Korean Sleep Scale(Oh, et al., 1998). The data were analyzed by SPSS WIN 12.0 program using descriptive statistics, Pearson Correlation, and Stepwise Multiple Regression. Result: The result were as follows. 1. The scores of fatigue of subjects averaged $4.95{\pm}1.83$, degree of fatigue was $5.85{\pm}1.98$, and influence of fatigue was $4.04{\pm}2.09$. 2. The mean score of the degree of physical dysfunction, pain, sleep disorder, and depression were $1.42{\pm}0.38,\;8.15{\pm}3.58,\;1.86{\pm}0.67,\;and\;1.85{\pm}0.46$ points respectively. 3. The subject's total fatigue score, physical dysfunction, pain, sleep disorder, and depression was correlated positively(r=.44, r=.28, r=.29, r=.27, p< .01). 4. The main influencing factors on the fatigue were physical dysfunction and sleep disorder. These two main variables made it possible to explain 23.0% of the variance in fatigue. Conclusion: Therefore, nursing interventions for fatigue experienced women with rheumatoid arthritis would be focused to decrease physical dysfunction and sleep disorder.

• Journal of Korean Academy of Nursing
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• v.30 no.3
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• pp.731-740
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• 2000

A study was done to identify the differences of women's perception of fatigue according to the period of pregnancy. Questionnaires were collected from 510 normal pregnant women in 3 University Hospitals in Korea from April to November of 1999. The questionnaires used to measure pregnant women's fatigue were the "Subjective Symptoms of Fatigue Test" designed by the Research Committee of Industrial Fatigue in Hygienic Association of Japanese Industry. The collected data was analyzed by SPSS-Win. The results revealed that there was a significant difference according to the periods of pregnancy: The degree of fatigue was the highest in the first trimester and then third and second trimester in decreasing order (F=89.53, p=0.000). The degree of fatigue was also compared with the respect to the general characteristics of women: There were statistically significant differences according to number of pregnancy (t=6.41, p=0.000), expectation of pregnancy (t=-291, p=0.004) and weight change (F=8.07, p=0.000). Therefore, variable nursing intervention should be provided to alleviate the fatigue according to the each trimester of pregnant period. Especially the nursing intervention program to alleviate the physical fatigue in the first trimester is necessary.

• Structural Engineering and Mechanics
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• v.49 no.2
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• pp.225-235
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• 2014

Cold expansion is an efficient way to improve the fatigue life of an open hole. In this paper, three finite element models have been established to bind the crack growth from an expanded hole and simulated. Expansion and its degree influence are studied using a numerical analysis. Stress intensity factors are determined and used to evaluate the fatigue life. Residual stress field is evaluated using a nonlinear analysis and superposed with the applied stresses field in order to estimate fatigue crack growth. Experimental tests are conducted under constant loading. Results of this investigation indicate expansion and its degree are beneficial to fatigue life and a good agreement was observed between FEM simulations and experimental results.

• Journal of Korean Public Health Nursing
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• v.16 no.2
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• pp.271-284
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• 2002

This study was to provide basic materials to help reduce the fatigue by analyzing what effective factor the fatigue of hospital nurses in Gwangju and Jeonnam region. and what causes their fatigue. This descriptive research by Questionaires includes two hospitals in Gwangju. and seven hospitals in Jeonnam region, total 9 hospitals sampled at convenience sampling. The periods of collecting data was from Jul.22, 2002 to Jul. 30, 2002. Multidimensional Fatigue Scale; MFS, developed by Jang Se-Jin(2000) was taken to measure the fatigue. All collected materials were got the statistics by SAS for Windows Release 8.01. The result of this study was as follows. 1. This study included total 740 nurses, whose age ranged from 22 to 50; 30 years old by average. Nurses fatigue mean score was 90.24 (the scope by the measuring instrument is 19-133). Nurses at University Hospitals marked 92.36 and those at General Hospitals marked 87.91 in the mean score of fatigue. 2. They kept tired at work, and felt more tired while working at computer in the hospital. 3. The part of body in which they felt fatigue was the calf and $feet(36.6\%)$, the shoulders and back of the $neck(30.7\%)$, and the whole $body(10.8\%)$ and the reason that they felt tired at work was mental $stress(33.0\%)$, overworking(25.2\%)$, and irregular working $conditions(14.7\%)$ in order. 4. The solution to their fatigue at work appeared nothing by $50.1\%$, and the way of releasing fatigue after work indicated getting some $sleep(30.8\%)$, and taking a bath or a $shower(21.7\%)$ in order. 5. The degree of fatigue depending on whether they were satisfied with their pay and labor condition appeared low: and when they were satisfied with doctors. and when they were getting on well with caregivers. 6. The effective factor of the degree of fatigue appeared: the influence that fatigue in the hospital makes on daily life was $10.6\%$, the cause of fatigue at work, $9.3\%$, time of fatigue at work, $7.8\%$, the relationship with caregivers, $5.3\%$. and these explanatory$(R^2)$ variables.$33\%$. To conclude. the degree of nurses' fatigue appeared high. and it was higher in nurses at University Hospitals than in ones at General Hospitals. In addition, the influence that fatigue from the hospitals made on daily life was the most explanatory.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.6 no.3
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• pp.477-492
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• 1999

The disease patterns among the Korean was shifted from acute and infectious diseases to chronic diseases. According to the these disease patterns trends, people have concerned about the health promotion and health behaviors. Pender's(1996) revised health promotion model(HPM) is consist of three categories; Individual characteristics and experiences, Behavior-specific cognitions and affect, behavioral outcome. Of these categories, individual characteristics and experiences, this category of variables is considered to be of biological, psychological and socio-cultural personal factors, especially, individual fatigue. Futhermore. these variables constitute a critical core for nursing intervention, as they are subject to modification through nursing actions. But there is no few the research of the relationship between the fatigue and health promotion. Therefore, the purpose of this study is to investigate the correlation between the fatigue and health promoting life style among a rural college students. Additionally, this descriptive correlational study identified the relation of demographic factors and fatigue, health promoting life style. From June 20 to 26, 1998, a convenience sample of 270 college students completed the questionnaire of the fatigue and health promoting life style profile which were developed by the Yoshitake(1978) and Walker, et al.(1987), respectively. The descriptive correlational statistics, mean, t-test, ANONA, Pearson correlation coefficient were used to analyze the data gathered with SAS pc+ program. The results were as it follows: 1. The average fatigue score of the subjects was $64.93{\pm}12.89$. Fatigue scores by subcategory were physical symptoms($23.5{\pm}4.87$). psychological symptoms($22.11{\pm}4.66$) and neuro-sensory symptoms($19.32{\pm}5.14$). With the respect to the demographic characteristics of the subjects, there were statistically significant differences between the demographic factors and fatigue, especially, sex(t==3.69 p<0.01), major(t=-2.89 p<0.01). the experience of family illness(t=2.76 p<0.01). 2. The average health promoting life style item score of the subjects was $2.33{\pm}0.33$. In the subcategories, the highest degree of performance was self-actualization(2.94), following interpersonal support(2.81). stress management(2.33), exercise(2.20), nutrition(2.10), and the lowest degree was health responsibility(1.73). There were the significant differences on the learning of health education(t=2.00 p<0.01). religion(F=3.01, p<0.05), circle activity(t=2.07, p<0.05), nutrition control(t=5.25, p<0.01) of demographical factors with the health promoting life style. 3. The correlation between the fatigue and health promoting life style made statistically no significance(r=-0.09731, p>0.05). But there was negative significant relationship between health promoting life style and psychological symptom as a fatigue subcategory(r=-0.15721, p<0.05). The self-actualization showed negative significant correlation with all fatigue subcategory. The health responsibility showed significant relationship with total fatigue(r=0.13050. p<0.05). For further research, it suggests to replicate the correlational and causal study between the fatigue and the health promoting life style using the another fatigue scale which is able to measure the subjective and objective fatigue degree. And it needs to develop the nursing intervention program for maintaining and promoting the health behavior as well as for decreasing the college students's fatigue.