• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.37 no.2
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• pp.147-155
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• 2009

The buckling and failure of filament wound thick composite cylinders under external hydrostatic pressure were investigated by the finite element analysis and test. ACOS, MSC.NASTRAN, and MSC.MARC were used for finite element analysis. T700 carbon-epoxy filament wound composite cylinders were fabricated to have winding angles of $[\pm30/90]_{FW}$, $[\pm45/90]_{FW}$, $[\pm60]_{FW}$, $[\pm60/90]_{FW}$, and tested to verify the finite element analysis. Among the softwares, ACOS predicted buckling load the best with about 1.7~14.3% deviation from test. Analysis and test shows cylinders do not recover the initial buckling pressure after buckling and directly lead to final failure.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.10
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• pp.6134-6141
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• 2014

This study analyzed the gap in perception between communication with parents and filial piety according to the general characteristics of teenagers. The test subjects were high school students from academic and vocational school from different districts of Seoul. A survey was conducted from March to July of 2014 to 290 high school students. Data analysis was conducted on the SPSSWIN 18.0 program using a t-test, one-way analysis of variance, correlation analysis, and other tests. The empirical analysis of the experiments were verified at the significance level of 5%. First, communication with fathers differed significantly depending on the school division, economic class, religion; and communication with mothers differed significantly depending on school division, grade-level, academic performance, domestic discipline, and economic class. Second, the perception of filial piety showed a significant positive correlation with the communication with the mother; and with the communication with the father. The implication of this study is that better communication between the parents and teenagers correlate with the higher filial piety according to the general characteristics of teenagers, and should become a central material for policy.

• Journal of the Society of Naval Architects of Korea
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• v.38 no.3
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• pp.93-106
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• 2001

T-joint and hopper knuckle joint models are typical welded joints in ship structure, which are very susceptible to fatigue damage under service condition. Fatigue test and fracture mechanical analysis were performed on these joints to find out characteristics of fatigue behavior. Unified S-N curve was developed from the test results of these two types of joint using hot spot stress concept, and also propagation life was also estimated using Paris' crack propagation law. Residual stress effect on propagation life was considered in calculating propagation life, as was done with thermo-elasto-plastic FE analysis and residual stress intensity factor calculation. Fatigue life of similar kinds of welded joint could be predicted with this unified S-N curve and fracture mechanical analysis technique.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.11 no.6
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• pp.807-823
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• 2018

The purpose of this study is to analyze whether there is a financial incentive effect by analyzing the difference of educational performance between the specialization department students who receive financial support and the students who do not receive support. This study collected survey data of 334 students including 290 students who were financially supported and 44 students who were not financially supported. Through the collected data, frequency analysis and descriptive statistics analysis were performed on the general characteristics of the subjects. T-test was conducted to analyze the difference of teaching & learning performance between students with financial support and those who did not, and then the difference analysis by grades was F-test. The average value of the subjects' teaching & learning satisfaction scores was 2.99, and the result was higher than that of the female students. The higher the age, the higher the grade, the higher the grade, the higher the financial support students were. The average of teaching & learning achievement composition items of the survey subjects was 2.27, and it was found that male students, older students, and students who received financial support had higher average of teaching & learning outcomes than students who did not receive financial support respectively. Students who receive financial support have higher teaching & learning satisfaction and outcomes than students who are not financially supported. The longer the period of financial support, the older the better, and the male students are more satisfied with the teaching & learning, the better the teaching & learning.

• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.1
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• pp.16-24
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• 2001

The purpose of this study was to evaluate the specificity, sensitivity, and diagnostic power of caries activity test using laser fluorescence. The subjects of this study were 50 children of $7\sim9$ years old. Fluorescence from initial carious lesion of teeth illuminated by an argon laser(480nm) was observed and photographed with barrier filter. Visual examination for the dDfFtT rate and Streptococcus mutans colony counting was done to evaluate correlation with caries activity test using laser fluorescence. Data analysis was accomplished by Axelsson's method. The results from the present study can be summarized as follows: 1. There was positive correlation $(\gamma=0.48)$ between laser fluorescence test and Streptococcus mutans count. And also positive correlation $(\gamma=0.39)$ exists between laser fluorescence test and dDfFtT rate (P<0.01). 2. Positive correlation $(\gamma=0.27)$ between Streptococcus mutans colony count and dDfFtT rate was found(P<0.05). 3. When dDfFtT rate was defined to standard testing method, the specificity, senstivity, and diagnostic power of laser fluorescence test were 44.4%, 85.7%, and 87.8%. 4. When dDfFtT rate was defined to standard testing method, the specificity, senstivity, and diagnostic power of S. mutans colony counting were 77.8%, 92.9%, 84.8%. 5. When S. mutans colony counting was defined to standard testing method, sensitivity, specificity and diagnostic power of laser fluorescence test were 40.0%, 84.8%, 95.1%. In regard to above results, laser fluorescence test considered to be accurate and reliable method for determining caries activity because of it's close relationship with caries susceptibility test and caries experience measurements. And it was also considered to be practical because it would be simple, inexpensive, and time saving method.

• Journal of the Korea Convergence Society
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• v.11 no.8
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• pp.351-360
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• 2020

This study is mixed design to measure the effects of case-based learning and the Cornell notes-taking system in human anatomy course, the basic course in nursing, on self-directed learning ability, critical thinking dispositon, and teamwork of nursing students. Among those who completed anatomy course, 34 underachieving students were targeted and surveyed before and after classes, and interviewed on case-based learning and Cornell notes-taking system. For quantitative analysis, SPSS/WIN 21.0 was used for frequency analysis, paired t-test, and Pearson's correlation coefficients. For qualitative research, content analysis was performed. The results showed significant increases in self-directed learning ability(t=-9.69, p<.001), critical thinking dispositon(t=-7.75, p<.001), and teamwork (t=-12.43, p<.001) in underachieving nursing students. In addition, there was a significant correlation between self-directed learning ability, critical thinking dispositon, and teamwork. In conclusion, case-based and Cornell notes learning methods were effective in helping underachieving students enrolled in human anatomy course. There is a need for continuous research on the use of case-based and Cornell notes in other courses.

• Journal of Distribution Science
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• v.13 no.8
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• pp.91-96
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• 2015

Purpose - This study reviews the delivery of child welfare service quality and examines how the dimensions of the variables of customer satisfaction impact the results from a service distribution perspective. This study differs from existing research since it proposes that a recognized level of child welfare service quality is necessary to achieve customer satisfaction from the perspective of service distribution. Research design, data, and methodology - This study explores child welfare service quality factors that affect customer satisfaction. The study examines and analyzes demographic variables, service quality dimensions, and the causal relationships between child welfare service quality and customer satisfaction. Data from 300 child welfare cases were collected from organizations in Korea in the areas of Busan and Gyeongsangnamdo. The methods of analysis are as follow. First, using descriptive analysis frequency, the percentages were evaluated to assess the demographic variables. Second, Cronbach's α was used to test reliability and to evaluate the internal consistency of the measuring of items. Third, multiple regression analysis was conducted to find out how much the independent variable can affect customer satisfaction. Results - Five factors of child welfare service quality were identified in three categories: process quality (assurance, empathy), results quality (reliability, caring), and physical environment quality (tangibles). There were significant differences among the effects of the child welfare service quality factors on customer satisfaction. A multiple regression analysis was done with process quality (assurance, empathy), results quality (reliability, caring) and physical environment quality (tangibles) to test the hypothesis: assurance (t=2.434, p<0.05), empathy (t=3.677, p<0.001), reliability (t=3.271, p<0.05), caring (t=4.380, p<0.000), and tangibles (t=3.654, p<0.01) had a positive influence on child welfare service quality from a service distribution perspective. Therefore, hypotheses 1, 2, 3, 4, and 5 were supported. In addition, multiple regression analysis on the effects of the variables showed that caring (β=0.273), empathy (β=0.246), tangibles (β=0.265), reliability (β=0.152), and assurance (β=0.131) all had a positive and strong influence on child welfare service quality from a service distribution perspective. Therefore, all child welfare service quality categories (process, results and physical environment quality) were positively statistically significant. Conclusion - In this study, the main findings can be summarized as follows. First, the quality of service of child welfare consists of three dimensions of quality: process quality, results quality, and physical environment quality. The results of the multiple regression analysis also showed that caring and reliability were confirmed as more meaningful variables by the increasing loading factors. Second, the family members involved in child welfare proposed caring as the most important variable among the dimensions of service quality. Third, the results of the hypothesis testing using regression showed that all child welfare service quality factors had a positive impact on customer satisfaction. The results of the study could provide useful information to help increase the effectiveness of delivery strategies for child welfare service quality from a service distribution perspective.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.473-474
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• 2009

In this study, a column member of an existing architecture finished with gypsum board was assumed to examine fire resistance characteristics according to the type and thickness of finishing material. All specimens showed spalling to the reinforcing part after fire resistance test. For temperature characteristics, rapid temperature increase of 100${\sim}$200 $^{\circ}C$ was shown between 35 ${\sim}$ 60 minutes in the sequence of 9.5 T, 9.5 T (2 pieces), 12.5 T, 15 T and fire resistant 12.5 T. The analysis suggested that finishing materials with better fire resistance are necessary.

• Journal of the Korean Home Economics Association
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• v.36 no.10
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• pp.131-144
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• 1998

The purpose of this study was to examine the differences of symbolic consumption of adolescents, and the effects of demographic factors on the symbokic consumption in clothing. Data were administered to 957 adolescents in middle, high school, and college students living in Seoul, Chonju, Sunchon, Yousu, and Kwangyang from May to June 1997. For analysis of the data, factor analysis, t-test, one-way ANOCA, duncan's multiple range test, and multiple regression analysis were employed. The results of this study were summarized as follows. 1) Symbolic consumption in colthing were shown to have the significant differences accoding to age, gender, the level of urbanization, parent's education, father's occupation, social stratification groups. The higher the age, the level of urbanization, and parent's education, father's occupation, social stratification is, or the female, the higher is symbolic consumption in clothing. 2) According to the results of the regression analysis examining the rerlative influences of variables affecting symbolic consumption in clothing, the relative importance of the variables are in order of; income, gender, age, mother's education, residence, and their explanatory powere totalled 11.5%.

• Journal of Family Resource Management and Policy Review
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• v.4 no.1
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• pp.15-28
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• 2000

The purpose of this study was to examine the knowledge about savings of customers who utilize Investment Trust Company and to analyze the factors affecting it. The data for the analysis were collected by structured questionnaires and consisted of 191 customers who utilize Investment Trust Company. Descriptive. Descriptive Statistics including percentage, frequency, means, and standard derivation, t-test, one-way ANOVA with Scheffe test, multiple regression analysis were used to analyze the data. The following is a summary of major findings. 1) The customers knowledge about savings showed generally low-level. Especially the knowledge about tax and regulation of savings were the areas shown the lowest level. 2) The age, marital status, education and occupation of customers and total period of utilizing company were the factors affecting the knowledge of customers in the one-way ANOVA analysis. 3) The result of regression analysis indicated that age of customers and total periods of utilizing company were the significant predictors of customers’knowledge. These two variables explained 25.77% of variance of customers’knowledge about savings.