• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.11a
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• pp.69-73
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• 2009

Combustion test results of 1/2.5-scale thrust chamber for 75tonf-class liquid rocket engine were described. The thrust chamber has chamber pressure of 60 bar, propellant mass flow rate of 89 kg/s, and nozzle expansion ratio of 12. The combustion tests were conducted to verify the combustion performance, the regenerative cooling performance and the durability of thrust chamber at design point condition, and then were performed to confirm the operation and the combustion performance at low combustion pressure condition. All the tests had been successfully executed without the damage of the hardware. These test results present a possibility of hot firing test at low combustion pressure condition, and can be used as fundamental data to predict the combustion performance at design point condition for 75 tonf thrust chamber.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.110.2-110.2
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• 2012

We investigate a cool loop and a dark lane over a limb active region on 2007 March 14 by the Hinode/EUV Imaging Spectrometer (EIS). The cool loop is clearly seen in the EIS spectral lines formed at the transition region temperature (log T = 5.8). The dark lane is characterized by an elongated faint structure in coronal spectral lines (log T = 5.8 - 6.1) and rooted on a bright point. We examine their electron densities, Doppler velocities, and non-thermal velocities as a function of distance from the limb using the spectral lines formed at different temperatures (log T = 5.4 - 6.4). The electron densities of the cool loop and the dark lane are derived from the density sensitive line pairs of Mg VII, Fe XII, and Fe XIV spectra. Under the hydrostatic equilibrium and isothermal assumption, we determine their temperatures from the density scale height. Comparing the scale height temperatures to the peak formation temperatures of the spectral lines, we note that the scale height temperature of the cool loop is consistent with a peak formation temperature of the Mg VII (log T = 5.8) and the scale height temperature of the dark lane is close to a peak formation temperature of the Fe XII and Fe XIII (log T = 6.1 - 6.2). It is interesting to note that the structures of the cool loop and the dark lane are most visible in these temperature lines. While the non-thermal velocity in the cool loop slightly decreases (less than 7 km $s^{-1}$) along the loop, that in the dark lane sharply falls off with height. The variation of non-thermal velocity with height in the cool loop and the dark lane is contrast to that in off-limb polar coronal holes which are considered as source of the fast solar wind. Such a decrease in the non-thermal velocity may be explained by wave damping near the solar surface or turbulence due to magnetic reconnection near the bright point.

• Journal of Digital Convergence
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• v.17 no.11
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• pp.387-394
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• 2019

The purpose of this study was to identify the moderated effects of emotional intelligence on the relationship between transition shock and adaptation on clinical practice among nursing students. Subjects were 185 associate nursing students associate nursing students(3rd). The data were collected using self -report questionnaire from May 1 to June 14, 2019. Data were analyzed by descriptive statistics, t-test, ANOVA, Pearson correlation and hierarchical multiple regression with SPSS/WIN 23.0. Mean point of transition shock(4 point scale) was 2.32. Mean point of emotional intelligence(5 point scale) was 3.61, and adaptation on clinical practice(5 point scale) was 3.40. Transition shock were significantly negative correlation with emotional intelligence(r=-.26. p <.001) and adaptation on clinical practice(r=-.43. p <.001) in nursing students. Emotional intelligence were significantly positive correlation with adaptation on clinical practice(r=.36. p <.001). Emotional intelligence has been shown to modulate the relationship between transition shock shock and adaptation on clinical practice(${\Delta}R^2=0.21$, p <.001). Therefore, to decrease the transition shock and to increase the adaptation on clinical practice of nursing students, It is necessary to develop the program for increase emotional intelligence of nursing students.

• International Journal of Fluid Machinery and Systems
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• v.4 no.2
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• pp.229-234
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• 2011

For Lift-type Vertical Axis Wind Turbine (VAWT), it is difficult to evaluate the performance through the scale-model wind tunnel tests, because of the scale effect relating to Reynolds number. However, it is beneficial to figure out the critical value of Reynolds number or minimum size of the Lift-type VAWT, when designing this type of micro wind turbine. Therefore, in this study, the performance of several scale-models of Lift-type VAWT (Reynolds number : $1.5{\times}10^4$ to $4.6{\times}10^4$) was investigated. As a result, the Reynolds number effect depends on the blade chord rather than the inlet velocity. In addition, there was a transition point of the Reynolds number to change the dominant driving force from Drag to Lift.

• Korean Journal of Child Studies
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• v.12 no.2
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• pp.78-93
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• 1991

The purpose of this study was to develop a rating scale for measuring children's temperament. The subjects were 622(324 boys and 298 girls) 3-to 7-year-old children. The temperament rating scale was composed of 50 items(4-point Liken scales) was based on mother's interview, RITQ and PTQ. The raters were the subjects' mothers. The data were analysed on dimensions of validity, reliability, and item discrimination. Statistical methods were factor analysis, ${\chi}^2$-test, and calculations of Pearson's r Cramer's V and Cronbach's $\alpha$. On validity 5 factors were extracted, which explained 84% of the total common variance. The 5 factors were named 'malleability', 'activity', 'sensitive reactivity', 'eating habits & physical constraints', 'physiological rhythmicity'. Regarding reliability, Cronbach's $\alpha$ appeared between .66 and .81 among the 5 factors. Regarding item discrimination, the degree of discrimination on all 50 items was significant and acceptable.

• Journal of the Korean Home Economics Association
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• v.39 no.2
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• pp.85-95
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• 2001

This study was carried out to obtain the information concerning the perception and utilization patter of the housewives about the edible oil and fats. Data were obtained through questionnaires from 442 housewives in Chonbuk area. The eating frequency of food that used oil & fat was affected by age, residing area and educational level. family's preference score of food that used oil & fats was 3.34 point in the 5 point scale. 47% of the subjects answered that the intake rate of oil & fats had more from vegetable oils than animal sauces. Most of the subjects had negative response such as increased cholesterol and body weight for psychological state after the intake of food that used oil & fats. The main reason why some housewives did not use frequently oil & fats was inconvenience of tidying up. The kinds of the oil & fat used frequently were soybean oil, sesame oil, com oil and perilla oil. The nutrition knowledge score rotated to oil & fat was 7.62 point in the 10 point scale. The eating frequency of food that used oil & fats and its preference were positively correlated. These results indicate that the housewives haute a widespread tendency to pursue a health and convenience in the utilization of edible oil & fats.

• The Journal of Korean Physical Therapy
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• v.22 no.1
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• pp.83-90
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• 2010

Purpose: This study aimed to determine the degree of job stress and self-esteem of physical therapists as well as the correlation between the two variables. Method: This study targeted 218 physical therapists of Busan City, and was carried out from July 16 to August 6, 2009 as survey research. A structured questionnaire referring to advance researches was used as a research tool. Job stress symptoms were measured one a 5 point scale, the higher the point total, the higher the job stress. Self-esteem was measured on a 4 point scale, the higher the point total, the lower the self-esteem. After data collection we determined descriptive statistics, and did reliability analysis, factor analysis, Spearman's correlation analysis, and regression analysis. Results: Reliability analysis indicated that reliability for the job stress questionnaire was 0.93 and for the self-esteem was 0.83. The average job stress score of physical therapists was 1.19 points which was not high. The average self-esteem score was 1.76 points, whichwas high. It appeared that the higher the self-esteem, the lower the job stress. Also, self-esteem had an influence on psychological symptoms among job stress factors. Conclusion: Job stress and self-esteem of physical therapists are well-correlated and influence each other. Accordingly, self-esteem can be used as a variable for adjusting job stress of physical therapists.

• Journal of Korean Public Health Nursing
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• v.30 no.1
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• pp.5-16
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• 2016

Purpose: This correlational study was conducted to determine the relationship between health status and ego integrity of permanent elderly returnees from Sakhalin. Methods: We surveyed 94 permanent elderly returnees from Sakhalin, living in Gimpo, Korea. Data were analyzed using the SPSS/WIN 18.0 program for descriptive statistics, t-test, $Scheff{\acute{e}}$ test, ANOVA, and Pearson correlation coefficient. Results: The mean score of total health status was 3.7 on a 5 point Likert scale. The mean score of ego integrity was 3.6 on a 5 point Likert scale. The health status showed significant correlation with the ego integrity of the permanent elderly returnees from Sakhalin. Conclusion: In the present study, although the health status of the permanent elderly returnees from Sakhalin appeared to be good, the lack of awareness about health care and the need for ego integrity, is in itself the actual suffering. Thus by providing health education along with medical information can enhance the health management. And, this practice can be self regulating for the society and can provide institutional support for the permanent elderly returnees from Sakhalin, which they require.

• Journal of the Korean Society of Food Culture
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• v.24 no.4
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• pp.440-450
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• 2009

The purposes of study were to survey the status of nutrition education in school and investigate the perception of nutrition teacher candidates concerning the direction and ideal method for nutrition education. A questionnaire was distributed to 554 nutrition teacher candidates from August to October, 2006. A total of 468 usable data were collected (84.5% response rate). The statistical data analysis was completed by using SPSS for Windows (ver. 10.0) for descriptive analysis, ANOVA and $X^2$-test. About 52% of respondents had nutrition education teaching experience. Half of the respondents indicated that the necessity for nutrition education stemmed from their own need for such education. The main problem in students' dietary life was 'the increasing intake of processed foods, instant foods and fast foods (4.23 out of Likert 5 point scale)' and the major nutritional problem was 'high calorie intake with low essential nutrients (3.96 out of Likert 5 point scale)'. Over half the respondents (53.4%) recommended that nutrition education be oriented towards behavioral change rather than knowledge delivery. Social learning theory was preferred mostly as an theory apt to nutrition education (60.3%) and the most effective means of education was referred to organizing the regular class for nutrition education (50.5%). The 'playing such as songs or game' was reported as both effective and realizable method in nutrition education.

• Therapeutic Science for Rehabilitation
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• v.10 no.4
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• pp.25-38
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• 2021

Objective : This study aimed to establish an analytic methodology that can objectively evaluate the proverb comprehension levels that vary based on the aging process. Method : This study recruited 70 normal elderly aged ≥ 65 years and performed proverb comprehension tasks using an explanation method. A scoring estimation method was designed on 3 and 5-point scales. The difficulty and discrimination levels were calculated based on the two scales, thereby selecting the final questions and evaluation scale. Results : First, the item discrimination index on the 5-point scale was relatively higher than that on the 3-point scale, and 10 items were finally selected. Second, in terms of proverb comprehension ability, the elderly group aged 70 ~ 84 years showed significantly lower performance than those aged 65 ~ 69 years. Additionally, subjects with ≥ 10 years of education showed significantly higher performance than those with 9 ≤ years of education. Third, the performance of the proverbs comprehension task negatively correlated with the reaction time of the executive function task. Conclusion : Proverb comprehension is a task that can distinctively show a deterioration of brain functions in line with the aging process even among the normal elderly group and therefore, can estimate the difference more effectively with an increase in the score of the evaluation scale.