• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.1
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• pp.17-22
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• 2016

The activation energy of a material is an important factor that significantly affects the lifetime and can be used to develop a degradation model. In this study, a thermal analysis was carried out to evaluate and collect quantitative data on the degradation of insulation materials like EPR and CSP used for nuclear power plant cables. The activation energy was determined from the relationship between log ${\beta}$ and 1/T based on the Flynn.Wall.Ozawa method, by a TGA test. The activation energy was also derived from the relationship between ln(t) and 1/T based on isothermal analysis, by an OIT test. The activation energy of EPR derived from thermal analysis was used to calculate the accelerated aging time corresponding to the number of years of use, employing the Arrhenius equation, and determine the elongation corresponding to the accelerated aging time.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.34 no.11
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• pp.70-75
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• 2006

The cabin pressurization system response should be consistent with the design limits such as the cabin pressure schedule, the pressure regulation tolerance, the maximum rate of pressure change during normal and abnormal operation and the maximum cabin air inflow rate change. In this paper, the results of pressure loss analysis and flight test for cabin pressurization system of T-50 advanced trainer are introduced. The pressure tolerance at unpressurized condition using calculated exit area of pressurization components through pressure loss analysis is predicted. Pressurization components of D company are selected and the predicted pressure tolerance is in good agreement with flight test results. Finally, T-50 pressurization system is verified by some flight tests of T-50 advanced trainer to comply with various pressurization design criteria of MIL-E-18927.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.3
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• pp.1153-1162
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• 2010

The purpose of this study was to examine the impact of pregnant women's participation in gymnastic exercise on their body evaluation and pregnancy stress. The subjects in this study were 100 female pregnant adults who were aged between 20 and 39 and resided in the region of Gangbook, Seoul. Out of them, 49 participants got pregnancy exercise, and 51 women didn't. A SPSS WIN 15.0 program was utilized to analyze the collected data, and frequency analysis, factor analysis, reliability analysis, t-test, one-way ANOVA, Scheffe test and multiple regression analysis were conducted. As a result of making a statistical analysis of the data, the following findings were given: First, the demographic characteristics of the pregnant women made differences to their body evaluation and pregnancy stress in part. Second, whether they got pregnancy exercise or not made partial differences to their body evaluation and pregnancy stress. Third, the body evaluation of the pregnant women exerted a partial influence on their pregnancy stress.

• Nuclear Engineering and Technology
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• v.44 no.7
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• pp.735-744
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• 2012

In order to quantify the flow distribution characteristics of APR+ reactor, a test was performed on a test facility, ACOP ($\underline{A}$PR+ $\underline{C}$ore Flow & $\underline{P}$ressure Test Facility), having a length scale of 1/5 referring to the prototype plant. The major parameters are core inlet flow and outlet pressure distribution and sectional pressure drops along the major flow path inside reactor vessel. To preserve the flow characteristics of prototype plant, the test facility was designed based on a preservation of major flow path geometry. An Euler number is considered as primary dimensionless parameter, which is conserved with a 1/40.9 of Reynolds number scaling ratio. ACOP simplifies each fuel assembly into a hydraulic simulator having the same axial flow resistance and lateral cross flow characteristics. In order to supply boundary condition to estimate thermal margins of the reactor, the distribution of inlet core flow and core exit pressure were measured in each of 257 fuel assembly simulators. In total, 584 points of static pressure and differential pressures were measured with a limited number of differential pressure transmitters by developing a sequential operation system of valves. In the current study, reactor flow characteristics under the balanced four-cold leg flow conditions at each of the cold legs were quantified, which is a part of the test matrix composing the APR+ flow distribution test program. The final identification of the reactor flow distribution was obtained by ensemble averaging 15 independent test data. The details of the design of the test facility, experiment, and data analysis are included in the current paper.

• Journal of Korean Public Health Nursing
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• v.29 no.3
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• pp.503-514
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• 2015

Purpose: The purpose of this study was to determine the effects of a happiness choice program based on reality therapy on subjective well-being and interpersonal relations in nursing students. Methods: A nonequivalent control group pre-posttest design was used. The participants were 45 nursing students, 22 in the experimental group, and 23 in the control group. They were from 2 different colleges of nursing located in 2 regions. The happiness choice program based on reality therapy was held 6 times over 6 weeks, taking 120 minutes per session. Nursing students' subjective well-being and interpersonal relations were measured. SPSS 18.0 using the ${\chi}^2$-test, t-test, and paired t-test were used in data analysis. Results: Nursing students in the experimental group showed significantly higher life satisfaction (t=3.81, p<.001), positive emotion (t=2.09, p=.042), and interpersonal relations (t=4.11, p<.001), while significantly lower negative emotion (t=-2.59, p=.013). Conclusion: The findings of this study suggest that a happiness choice program based on reality therapy could be a useful intervention for improving subjective well-being and interpersonal relations of nursing students.

• Steel and Composite Structures
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• v.2 no.1
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• pp.35-50
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• 2002

A series of tests on simple-welded plate specimens (SWPS) and T-stub tension specimens simulating some of the joint details in moment frame connections were conducted in this investigation. The effects of weld strength mismatch and weld metal toughness on structural behavior of these specimens were considered under both static and dynamic loading conditions. Finite element analyses were performed by taking into account typical weld residual stress distributions and weld metal strength mismatch conditions to facilitate the interpretation of the test results. The major findings are as follows: (a) Sufficient specimen size requirements are essential in simulating both load transfer and constraint conditions that are relevant to moment frame connections, (b) Weld residual stresses can significantly elevate stress triaxiality in addition to structural constraint effects, both of which can significantly reduce the plastic deformation capacity in moment frame connections, (c) Based on the test results, dynamic loading within a loading rate of 0.02 in/in/sec, as used in this study, premature brittle fractures were not seen, although a significant elevation of the yield strength can be clearly observed. However, brittle fracture features can be clearly identified in T-stub specimens in which severe constraint effects (stress triaxiality) are considered as the primary cause, (d) Based on both the test and FEA results, T-stub specimens provide a reasonable representation of the joint conditions in moment frame connections in simulating both complex load transfer mode and constraint conditions.

• Journal of Korean Academy of Nursing
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• v.42 no.6
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• pp.843-852
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• 2012

Purpose: In this study a recreational combination gymnastics program was provided for women 75 years of age or older and the effects on physical fitness (grip strength, static balance, ability to do complex movement), depression, cognitive function and quality of life were examined. Methods: A quasi-experimental study employing a nonequivalent control group, pre-post design was conducted. Participants included 53 women elders whose cognitive function was within the normal range. The women were assigned to an experimental group (27) or a control group (26). The intervention was conducted twice a week for a period of 12 weeks. Chi-square test, t-test, paired t-test, Wilcoxon rank sum test and Wilcoxon signed rank test were used for data analysis. Results: Following completion of the program, left grip strength (t=2.17, p=.035), right grip strength (t=2.04, p=.046), static balance (t=-2.18, p=.030), depression (z=-2.88, p=.004), cognitive function (t=3.96, p<.001), and quality of life (t=-3.19, p=.002) were significantly better in the experimental group. Conclusion: Findings from this study indicate that recreational combination gymnastics programs are effective in enhancing physical fitness, cognitive function, and quality of life and in decreasing depression for female elders and could therefore be regarded as positive programs for promotion of physical and mental health for older women.

• Journal of the Korea Computer Industry Society
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• v.9 no.5
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• pp.223-228
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• 2008

A case study to show MS Excel's convenient and powerful functions was conducted to test hypotheses with subway data. Quantitative variables were described using descriptive menu, and qualitative variables were described using histogram menu of a MS Excel software. Relationships were tested using regression menu, differences were tested using t-test menu, and factors were tested using variance-layout menu of a Excel software. Data input, management, and statistical analysis were done successfully with only a MS Excel software.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.10 no.1
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• pp.93-115
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• 1999

This Study is the summary of studies in analysis of‘Lecture Evaluation’made at H university where such evaluation for every course established has been carried out since 1990. This contains the contents of questionnaire drawn up through OMR scanner which has 7 fields with 10 items respectively. to investigate the general direction of the results, results of evaluation by lectures, different results of evaluation by fields, and the like. I applied such techniques of statistical analysis as T-test, analysis of variance table(Anova-table), and Regression analysis to examine the most important factor of successful lecturing.

• Journal of the Korea Society of Computer and Information
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• v.24 no.4
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• pp.177-183
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• 2019

The purpose of this study is to analyze the effect of behavior attitude and subjective norm on food festival behavior intention of married women living in Ulsan area. The data were analyed with PASW 18.0 using reliability analysis, frequency analysis, paired T-test, T-test, correlation analysis, one-way ANOVA and multiple regression analysis. The results were as follows. First, First, married women had a slightly higher passive behavior intention than aggressive behavior intentions on food festivals. Second, the more the experience of past food festivals, the higher the economic level, the higher the housewife's housewives, the higher the food festival behavior intention. Third, the behavioral intention of food festival increased with higher behavioral attitude and subjective norms. Fourth, subjective norms were the most influential variable for the behavioral intention of married women. Next, the behavior attitude for food festival was found.