• Journal of the Korean Society of Combustion
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• v.3 no.1
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• pp.71-78
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• 1998

The flame stabilization and the combustion characteristics of diffusion flame formed in the wake of a cylindrical bluff body with fuel injection are studied. With the turbulence generator, the flame stability limits and ion currents were measured and analyzed. The results from this experimental study are summarized as follows. The region with highest average value of ion currents in the middle of flame is moved to the upstream side by the turbulent components of main stream. The flame mass with partially active reaction is moved fast for uniform flow and turbulence generator G3, but the flame mass with relatively slow reaction is moved slowly for turbulence generator G1. If the turbulence generator with strong turbulent component is installed, the turbulent time scale is increased with movement from main stream side to recirculation zone as well as the flame stability limits is deteriorated. Though the special dominant frequency is not appeared in the eddy which exists in flame, high frequency characteristics are appeared in uniform flow and turbulence generator G3, and low frequency characteristics are appeared in uniform flow, turbulence generator G3 and G1.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.842-853
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• 2008

In the construction of dam, the key factor which decides the type of dam is security of materials resource. Because of the large scale earth work, the ability to supply the materials is essential part about economical efficiency. The research is the case study about controlling the plan to secure the material resources in the design of Buhang multipurpose dam. In case of Buhang multipurpose dam, at that time of basic design, it was planned to use a rock fill material. From the detail investigation about the river bed accumulative layer widely spread on the submerged district on the basic design, the research is accomplished to replace rock material with gravel material. After the investigation of whole reserves of gravel material, estimation of conformity as dam construction material from analysis of grain size distribution, the case study of oversea construction, and the material property comparison between rock fill material and gravel fill material, it is verified th possibility of using the gravel fill. Thereafter, the analysis of dam stability using a gravel fill material is accomplished. Finally, A gravel fill material can be used as the main construction material of CFRD, therefore the efficiency of resource recycling in the submerged area is maximized, and the established plan is more advantageous to stability, constructibility, environmentibility than the case of using a rock fill.

• Journal of the Korean Institute of Educational Facilities
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• v.20 no.6
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• pp.21-30
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• 2013

This study aimed to identify elementary school teachers' perceptions of various aspects of physical environments of a classroom. For the purpose, a survey questionnaire was administered to 982 classroom teachers(female 82.2%) working at 67 elementary schools(Seoul 55%) located in Seoul and Busan. According to the analyses of the survey data, 50.8% of the respondent teachers suggested 20-25 as an optimum class size. Also, 57% of the teachers were positive about the current size of a classroom($67.5m^2$), but evaluations of a classroom size were divided between the teachers who had more and less than 30 students in class. Furthermore, three factors, labelled as 'uniqueness', 'residential stability' and 'visually pleasing', were extracted from a factor analysis of the Semantic Differential Scale consisting of 24 adjectives evaluating a classroom environment. Teachers from Busan tended to rate higher in the uniqueness domain while female teachers scored higher in the domain of residential stability, respectively, compared to their counterparts. Overall, the teachers perceived their classrooms having no particular characteristics, but rated highly in terms of stability. In addition, it was found out that the teachers' requests for the improvement of a classroom environment were not so much as the increased size of a classroom as a reduced class size as well as educational facilities that are corresponding to a variety of instructional methods. In summary, this study confirmed that elementary school teachers' perceptions of a classroom environment varied according to such factors as sex, teaching career, grade of their concerned class, and class size.

• The Journal of the Korea Contents Association
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• v.21 no.3
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• pp.653-663
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• 2021

The purpose of this study was to examine the effects of ambivalent sexism and focusing manner on self-concept for middle-aged women, and to verify the factors that can help middle-aged women's positive self-concept. The self-concept scale, the focusing manner scale, and the ambivalent sexism scale were used for this study through the online community targeting middle-aged women aged 35 to 55. As a result of the analysis using SPSS 21.0, it was investigated that there was a significant positive correlation between hostile sexism and benevolent sexism. In addition, It was found out that ambivalent sexism had a significant negative effect on self-concept. It was found out that the high hostile sexism of ambialent sexism led to lowering the self esteem, emotional stability, problem solving stability, interpersonal relationship and interpersonal trust of middle-aged women. Focusing manner had a significant positive effect on self concept, but there were differences for each sub-factor. Express, accept, and keeping one's composure had a significant positive effect, while awareness had a negative effect, and reflecting attitude did not have a significant effect. Finally, limitations of this study were discussed.

• The Journal of Engineering Geology
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• v.33 no.4
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• pp.657-671
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• 2023

As large-scale earthquakes have occurred in Korea and their aftermath continues to be felt, laws and regulations on seismic design have been emphasized, and in Korea, the seismic design standards have been newly revised after the Gyeongju earthquake. In the revised seismic design standards, a stability review for the destruction of the support activity of the breakwater was newly added. Therefore, in this study, we conducted a stability analysis on the seismic reinforcement method for the study site, and checked the ground acceleration of the subgrade and the displacement of the structure over time. As a result of the stability analysis, the safety factor increased by at least 0.5 and up to 1.7. As a result of the time history analysis, the displacement of the superstructure decreased by up to 290 mm and down to 12 mm in both the shallow and deep sections before and after reinforcement, and the ground acceleration decreased by up to 5.33 m/s and down to 0.31 m/s after reinforcement.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.16 no.12 s.117
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• pp.1231-1237
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• 2006

The vibration of a running railway vehicle can be classified on lateral, longitudinal and vertical motions. The important factor on the stability and ride quality of a railway vehicle is the lateral motion. The contact between wheel and rail with conicity influences strongly on the lateral motion. In this study, an experiment for the vibration of a running railway vehicle was performed using a of the scale model of a railway vehicle. Also, the effects on the car-body, bogie and wheelset were examined for the weight and the stiffness of the second suspension system. The experimental results showed that the lateral vibration increases as the wheel conicity and stiffness of the second suspension system increase. And the lateral vibration of the bogie increases as the mass ratio between car-body and bogie increases. Also, the lateral vibration of the wheel becomes high at low speed, while the wheel of 1/20 conicity makes severe vibration at high speed running.

• Journal of Korean Academy of Nursing
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• v.38 no.3
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• pp.410-419
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• 2008

Purpose: The purpose of this study was to develop a stress measurement scale for Korean nursing students. Methods: Sixty preliminary items were selected by classifying 229 basic items extracted via literature review and Q-sorting method. In order to verify the reliability and validity of the preliminary instrument, data were collected from 617 nursing students in 2 colleges of nursing in Korea. Results: As a result of the item analysis, 58 items were selected. They consisted of 2 types of stress which were college-based stress (38 items) and clinical-based stress (20 items). Ten factors in college-based stress and four factors in clinical-based stress were extracted by factor analysis, and each had a total variance of 63.01%, and 64.93%. Cronbach's Alpha of those 58 items were .937 in college-based stress and .922 in clinical-based stress, which was high. Conclusion: This paper is meaningful in a way that it has developed a tool capable of measuring stress for nursing students, which reflects the characteristics of our country. It is recommended for further study to re-verify the relevance and stability of this measurement.

• Women's Health Nursing
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• v.11 no.2
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• pp.156-162
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• 2005

Purpose: The study was done to identify the relationship of symptoms of stress, cancer prevention behavior, the quality of life in women, and the factors influencing the quality of life. Method: The subjects of this study were 210 married women. They were living in Gyeonggi Province and Busan Metropolitan City. Symptoms of stress were measured by the Park's Stress Scale. Cancer preventive behavior was measured by Suh's Korean scale, and Smith Kline Beecham Quality of life' Scale by Dunbar. Data was analyzed with the SPSS program by ANOVA, Pearson's correlation, and Multiple Regression Analysis. Result: The higher scores of physical stress correlated with lower practice scores of cancer prevention behavior. Psychological and physical stress revealed negative correlations among sub-items of the QOL such as competence, psychological well-being, stability, physical well-being and activity. Multiple regression analysis revealed that the predictor of quality of life in the women was stress. A combination of symptoms of stress and cancer prevention behaviors accounted for 35.3% of the variance in the quality of life in the women. Conclusion: The most important factor influencing the quality of life of women was stress. Thus the study's findings can be useful in directing a comprehensive nursing care plan to improve the QOL of women.

• 한국노년학
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• v.29 no.3
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• pp.1141-1158
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• 2009

This study was conducted to explore the determinants of happiness for Korean Old People. A total of 105 Korean old people responded to open-ended questions about their happiness. From the content analysis of those reponses were happiness-related 70 items derived. Then 200 old people rated themselves on the list of those items. Factor analysis of those data ended up with 33 items of 8 factors, which were ①Family relationship, ②Religion, ③Financial ability, ④Health, ⑤Work/Job, ⑥ Psychological stability, ⑦Leisure, ⑧Public welfare. This Happiness Scale for the Korean old people, Subjective wellbeing Scale, Emotion experience Scale, and Self-esteem Scale were also administered to the identical 200 Korean old people. Results indicated that the construct validity of this new Happiness Scale for Korean old people was obtained. Finally, the implications and limitations of the present study and suggestions for further studies were discussed.

• Journal of Digital Convergence
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• v.16 no.5
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• pp.361-372
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• 2018

The purpose of this study was to develop an assessment scale for healthy aging of middle aged women. The data were collected from 385 middle aged women in two large cities in Korea. The development processes of the scale were followed: Development of preliminary items; Verification of content validity and reliability; Factor analysis and criterion validity of final items. Results: Factor analysis resulted in the creation of the final scale, which consisted of 38 items that were grouped into 9 factors: self achievement, physical change adaptation, psychological change adaptation, interpersonal relationships, menopausal symptom adaptation, economic stability, physical health, social support, social change adaptation. The explanatory variance was 64.03%. The reliability of the scale was Cronbach's ${\alpha}=.90$. Correlation of the scale with healthy aging and depression, established its construct and concurrent validity was r=-.69, p<.001. The scale was confirmed to have a relatively high validity and reliability. The findings of the study can be useful as a measurement to evaluate healthy aging of middle aged women. Future researches with the scale will be helpful for basic data for the program development to support healthy aging of middle aged women.