• Tunnel and Underground Space
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• v.14 no.4
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• pp.295-303
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• 2004

For the deep underground excavation site with the geological complexity of soft seam and hard rock, the numerical analysis and in-situ measurement on the behaviors of roadway and surrounding rock according to stepwise excavation of the steep soft seam are carried out. The strata behavior is modeled using elasto-plastic FEM considering the empirical failure criteria of Hoek ＆ Brown and the strain-softening model. Hydraulic pressure capsule, MPBX and tape extensometer are installed around the roadway for the in-situ measurement of rock stress and deformation. Despite the complexity of geology and excavation procedure, the elasto-plastic analysis considering the empirical failure criteria of Hoek ＆ Brown and the strain-softening model shows good agreement with the in-situ measurement. Comparison of numerical modeling with in-situ measurement enables to predict the behaviors of the roadway and to obtain design parameters for the excavation and support at depth.

• Proceedings of the Korean Geotechical Society Conference
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• 1991.10a
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• pp.289-311
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• 1991

Analysis of supported excavation system by Elasto-Plastic Isoparametric Finite Element Method and Elasto-Plastic Beam Method have been conducted for the simulation of stepwise underground excavation. Conventional methods, fixed Supported Beam and Spring Supported Beam method, also have been examined and compared with the results of elasto-plastic beam method and field data. Except unavoidable result of upward ground settlement near the top of retaining wall and relatively high bending moment of wall at each excavation level, satisfactory results have been derived using elasto-plastic isopara metric finite element method. The results from elasto-plastic beam analysis program, developed by the author, are proved to be fit field data in acceptable variance as shown in the paper. Displacement and bending moment, of the wall by conventional methods, both fixed supported beam and spring supported beam, are always underestimated than field data, and attention must be given that the diffence increases with deeper excavation depth and lower horizontal subgrade reaction of the ground.

• Korean Journal of Health Education and Promotion
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• v.6 no.1
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• pp.34-47
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• 1989

The changing trend of longevity from 1955 through 1985 and its interprovincal variation were studied with longevity rate as indicator. In order to detect the affecting factors of longevity rate, eleven urbanalizational, geographic-environmental, demographic and social-economic variables were employed to carry out multiple stepwise regression analysis. The data used for this study were from Population Census Reports 1955-1985 published by EPB and Year book of Public Health and Social Statistics 1986 published by Ministry of Health and Social Affairs and other reference. Subsequent to that longevity rate decreased during 1950's it has increased continuously by the yeat of 1980's. This trend was especially remarkable in the south area and the GIRI mountain area in Korea. The stepwise regression analysis shows that the longevity rates were significantly associated with the independent variables, and the dependent variables explained at the level of 93.7percent-99.9 percent. Longevity is a reflection of the demographic and socio-economic, environmental and health resourses factor etc., longevity problems cannot be dealt with in isolation. The possible research and services which could be provided by government will be discuss.

• Journal of Society of Preventive Korean Medicine
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• v.3 no.2
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• pp.171-182
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• 1999

This study was carried out to evaluate factors influencing on women of skin type using Pender's Health Promotion Model. For this purpose, we surveyed 159 women from July 1 to August 22, 1998. In results of stepwise logistic analysis, these factors was shown significant habit of practice and skin care experience (p<0.05). Groups which did not practice showed the probability of 13.49 times in neutral skin. Groups which experienced skin care showed the probability of 5.16 times in neutral skin. These results suggested that it was to develop the instrument for measurement of skin type.

• Journal of Korean Academy of Nursing
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• v.34 no.3
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• pp.576-585
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• 2004

Purpose: The purpose of this study was to identify the relationship between eating disorders, physical symptoms, depression and health locus of control. Method: The research design was a descriptive study done by using a constructive self-report questionnaire. A total of 464 elementary school girls were measured. The instrument was a constructive questionnaire that consisted 136 items. The subjects were divided into 4 groups according to the Body Mass Index (BMI). Data analysis was done by SPSS/WIN Programs using frequency, percentage, mean, SD, ANOVA, Pearson correlation coefficient, and stepwise multiple regression. Result: The score of eating disorders differed significantly by BMI : the score was highest in the group of obese students(F=4.208, P=.015). Stepwise multiple regression analysis revealed that the most powerful predictor of eating disorders was BMI. Conclusion: These results indicate that Korean elementary school girls need more education and counseling on diet. Also, we should take systematic efforts to reestablish the social standard of beauty to promote normal growth development.

• Child Health Nursing Research
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• v.9 no.3
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• pp.301-308
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• 2003

The Purpose of this study was to identify factors that influence the self-esteem of the schooler of families in poverty. A descriptive, correlational, and cross-sectional study design was used. The data were collected from February to March, 2001. Convenient sampling was done from 194 subjects living in Jeju Do, but 167 subjects among these were used for the study analysis. Hierarchical Stepwise Regression was used to identify significant factors. The results of this study were as follows: In general, self-esteem status of the schooler in poor families was relatively poor. In stepwise regression analysis, self-esteem status was significantly influenced by emotional home environment, duration of poverty and frequency of parent-child tactics. These variables explained 26.8％ of the variance of schooler's self-esteem. Conclusively, it is recommended that nursing intervention programs for schooler in poor family should be a focus to enhance the economic context as well as family effect.

• Journal of the Korean Home Economics Association
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• v.45 no.4
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• pp.29-42
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• 2007

The purpose of this study is to investigate the leisure and social support types which affect elderly depression. The study sample comprised 275 cases, and the analysis was performed by t-test, ANOVA, multiple regression and stepwise regression on SPSS ver. 10.0. The following three principle results were obtained: First, the types of leisure and social support differed according to domographic profiles. Second, among 6 sub-factors of leisure type, sports and viewing impressions activities contributed positively to elderly depression, as did emotional and appraisement supports among 4 sub-factors of social support. Third, stepwise regression analysis, conducted to determine the effect weights of factors of leisure types and social supports, showed that emotional support, social relationships activity, and viewing impressions activity strongly affected elderly depression in the order listed. Based of these results, the study suggested methods for developing an active leisure activities program which is necessary to minimize elderly depression.

• Korean Journal of Community Nutrition
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• v.3 no.5
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• pp.679-684
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• 1998

This study was conducted to investigate the determinants of obesity during adolescnece. A total of 726 adolescents living in rural areas in Korea had been observed for four years from 1992 to 1996 regarding their diet, sexual maturity, blood profile and physical growth. Stepwise multiple regression analysis was used to identify priorities fo the importance between the factors influencing obesity. The average nutrient intake over the three year period was higher than that of the Korean Recommended Dietary Allowances. The prevalence of obesity for the subjects based on BMI was 9.5%. Results of the stepwise multiple regression analysis showed that blood components and sexual maturity were more significant factors for determining the obesity than the dietary factors. The result may suggest that to understand obesity in children it is necessary to develop on analytical model for the children rather than using the existing analytical model developed mostly for adult patients of obesity. The model should include a wide range of variables such as diet, sexual maturity and changes in blood.

• The Journal of Korean Society for School & Community Health Education
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• v.14 no.3
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• pp.51-65
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• 2013

Objectives: The main purpose of this study was to compare influencing factors on depression between male and female students at the high school. Methods: The self-administered questionnaire survey was carried out on a convenience sample of 403 high school students. The data analysis procedure included frequency, ${\chi}^2$ test, t-test, ANOVA, Pearson correlation coefficients, and stepwise multiple regression using depression as the dependent variable. Results: There was a significant gender difference in depressive symptoms; the mean depression score of female students was higher than that of male students. Stepwise multiple regression analysis for depression revealed that the most powerful predictors (34%) were powerlessness and self-esteem for male students. On the other hand, the factors such as self-esteem, mother's occupation, and family fucntion were the most significant predictors (50%) for female students. Conclusion: The necessity of an intervention considering gender difference in high school students so as to prevent the occurrence of depression was suggested.

• Journal of Environmental Science International
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• v.16 no.11
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• pp.1301-1312
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• 2007

The objective of this study is to propose a critical storm duration forecasting model on storm runoff in small river basin. The critical storm duration data of 582 sub-basin which introduced disaster impact assessment report on the National Emergency Management Agency during the period from 2004 to 2007 were collected, analyzed and studied. The stepwise multiple regression method are used to establish critical storm duration forecasting models(Linear and exponential type). The results of multiple regression analysis discriminated the linear type more than exponential type. The results of multiple linear regression analysis between the critical storm duration and 5 basin characteristics parameters such as basin area, main stream length, average slope of main stream, shape factor and CN showed more than 0.75 of correlation in terms of the multi correlation coefficient.