• Journal of the Korean Society for Aeronautical & Space Sciences
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• 제37권10호
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• pp.1027-1037
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• 2009

The development of a combustion chamber for a 30-$ton_f$ regeneratively-cooled space liquid rocket engine is described. Starting from the development of bi-propellant swirl coaxial injectors, essential technologies were verified through subscale combustion chambers and afterwards applied to the full-scale combustion chambers. A total of 5 full-scale combustion chambers have been utilized to verify ignition, combustion efficiency and stability, cooling, and duration requirements. A total of 46 combustion tests were performed among which 23 tests were parallely performed with stability rating tests using a pulse gun device. The test results have revealed that the 30-$ton_f$ regeneratively-cooled combustion chamber fully complies to the performance and combustion stability requirements and thus concluded that the development is successfully completed.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• 제37권10호
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• pp.1038-1047
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• 2009

The development process of a gas generator for a 30-tonf pump-fed space liquid rocket engine is described. Starting from the development of an injector, followed by subscale and full-scale test specimens, the development of LOx/kerosene fuel-rich gas generator has been concluded successfully. Various analytical methods have been utilized in the course of design and the performance requirements have been verified experimentally through ignition tests, combustion performance and stability assessment tests and duration tests. The gas generator has proven its workability and stability within a defined operation window of varying chamber pressure and mixture ratio and demonstrated compliance to the performance and life time requirements.

• Korean Medical Education Review
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• 제15권1호
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• pp.46-53
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• 2013

The purpose of this study was to analyze the relationship among medical students' learning motivation, characteristics of multiple intelligence, and academic achievement. The participants were 144 medical students. The data were collected by administering learning motivation tests (self-confidence, self-efficacy, level of task, emotion of learning, learning behavior, failure tolerance, task difficulty, and academic self-efficacy), a multiple intelligence test (linguistic intelligence, logical-mathematical intelligence, musical intelligence, bodily-kinesthetic intelligence, spatial intelligence, interpersonal intelligence, intrapersonal intelligence, and naturalistic intelligence), and two semesters of grades. There is a correlation between multiple intelligences and learning motivation. Among academic self-efficacy of academic motivation, the self-control efficacy (0.28) and behavior (0.18) subscales are significantly positively correlated with academic achievement. However, the emotion subscale (-0.18) was significantly negatively correlated. Learning motivation was correlated with two of the eight multiple intelligence profiles: the intrapersonal intelligence (0.18) and bodily-kinesthetic intelligence (-0.19). The structural equation modeling analysis showed that the behavior and self-control efficacy subscales of intrapersonal intelligence had an impact on academic achievement. An analysis according to the academic achievement group showed significant differences in self-control efficacy and emotion subscales with intrapersonal intelligence. A positive relationship can be observed between learning motivation and some characteristics of multiple intelligence of medical school students. In light of the findings, it is worth examining whether we can control medical students' learning motivation through educational programs targeting self-control efficacy and intrapersonal intelligence.

• Perspectives in Nursing Science
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• 제16권2호
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• pp.84-97
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• 2019

Purpose: This study aimed to develop the Korean Prototype of Wellness Index (KP-WI) and identify the relationship between Koreans' health characteristics and wellness. Methods: The Wellness Index (WI) was translated into the primitive version of the KP-WI, considering the Koreans' culture and health behavior. It was administered to 223 service industrial employees at one workplace along with the Positive Affect and Negative Affect Schedule (PANAS) and Stress Questionnaire-Short Form. Data analyses included item-total correlation, Pearson's correlation coefficient, independent t-test, and one-way ANOVA. Results: The primitive version was modified to KP-WI based on the item-total correlation. The items considered to lower the reliability of the KP-WI were eliminated. Cronbach's ${\alpha}$ for each subscale ranged from .857 to .939. Perceived stress and negative emotions correlated significantly with wellness measured by KP-WI (r=-.29, p<.001; r=-.27, p<.001). Positive emotions correlated significantly with wellness (r=.60, p<.001). Conclusion: This study contributes to the development of Korean-style wellness indexes by developing a prototype and exploring the factors related to wellness.

• The Journal of Korean Obstetrics and Gynecology
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• 제27권4호
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• pp.15-24
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• 2014

Objectives: There were only small studies about the difference of the quality of life depending on blood stasis. We investigated that the blood stasis made the differences of quality of life. Methods: We recruited the participants stratified according to age and gender. The participants were assessed independently by two Korean medicine doctors more than 7 years of clinical experiences whether or not with blood stasis. And they responded at the questionnaire associated with blood stasis and SF-36. The analysis was done with IBM SPSS Statistics (ver. 21). Results: Total 101 participants were checked for with/without blood stasis. 40 participants were accord in the diagnosis with blood stasis by two doctors. Two researchers coincided in diagnosis with non-blood stasis in 42 participants. 19 participants showed the discrepancy between the assessment of blood stasis and they were classified as non-blood stasis. The mean age in group of blood stasis was $44.07{\pm}11.65$, it was not shown the significant difference comparing non-blood stasis group. The subscale of physical function (PF), role-physical (RP), bodily pain (BP), general health (GH), vitality (VT), mental health (MH) and role emotional (RE) in SF-36 were significantly low in the group of blood stasis. Blood test including biochemistry, fibrinogen, prothrombin time and D-dimer was not in abnormal range according to blood stasis without CRP. Conclusions: The patients that diagnosed of blood stasis showed the bad physical health status, and partially bad mental health. It is necessary to investigate whether Korean traditional treatment for blood stasis would be made improvement for quality of life. Moreover, the standardization of diagnosis on blood stasis would be needed.

• Journal of the Korea Fashion and Costume Design Association
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• 제21권3호
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• pp.37-53
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• 2019

The purposes of this study were to investigate Chinese female consumers' shopping orientation and clothing shopping behaviors on the internet and to find the differences in internet shopping behaviors of consumer groups segmented by clothing shopping orientation. The subjects were 417 women in their 20s and 30s from the Gillim Province, China. The research method was a survey, and the questionnaire consisted of a clothing shopping orientation subscale, clothing, their shopping behaviors via the internet, and the subjects' demographic characteristics. For data analysis, a frequency analysis, a cross-tab analysis, a factor analysis, a cluster analysis, ANOVA, and Duncan's multiple range test were performed. The results of this study were as follows. The clothing shopping orientation was derived using five factors (trend pursuit, pleasure pursuit, brand pursuit, economic pursuit, and convenience pursuit). Chinese female consumers were classified into three groups (hedonic group, ambivalent group, and practical group) by clothing shopping orientation. These three groups showed many significant differences in their clothing shopping behaviors on the internet. The hedonic group preferred the specialty and cross-border shopping malls, and considered product quality and trend as their main purchase motives. The ambivalent group considered the convenience of the purchase and trend as important motives as compared to the other groups, and they use more various product selection criteria. The practical group considered low price and convenience and the search simplicity of various products as major purchase motives. In addition, the hedonic and ambivalent groups had a higher purchase satisfaction and purchase intention from internet shopping than the practical group. This study suggested that clothing shopping orientation is one of the useful segmentation variables and fashion marketers needed to establish differentiated marketing strategies for each consumer group that is segmented by clothing shopping orientation.

• Nutrition Research and Practice
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• 제16권6호
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• pp.765-774
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• 2022

BACKGROUND/OBJECTİVES: It is important to determine Dysfunctional eating behaviors such as dietary restraint and overeating tendencies in order to provide weight management and acquire the right habits in children. The purpose of this study was to test the reliability and validity of Dutch Eating Behaviour Questionnaire Children (DEBQ-C) with Turkish preadolescent children. MATERIALS/METHODS: This research included 440 preadolescents (9.3 ± 6.9 years and 235 girls, 205 boys). The instrument is divided into three subscales, each with 20 items. Emotional eating, restrained eating, and external eating are the three subscales. Confirmatory factor analysis (CFA) was used to assess the construct validity of the Turkish version of the DEBQ-C, and Cronbach α values were computed to evaluate the subscale reliabilities. There were 20 observable variables and three latent variables in the hypothesized model. RESULTS: Fit indices for the hypothesized model were good (×2/degree of freedom = 1.96; root mean square error of approximation = 0.05; comparative fit index = 0.95; goodness of fit index = 0.93). These findings revealed that the Turkish version of the DEBQ-C has a factor structure that was identical to the three-factor structure of the original scale. The Turkish version of the DEBQ-C subscales has internal consistency coefficients ranging from 0.72 (external eating) to 0.86. (emotional eating). CONCLUSIONS: The DEBQ-C Turkish version is a viable and reliable tool for measuring overeating tendencies in Turkish preadolescents, according to the findings.

• Journal of Preventive Medicine and Public Health
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• 제55권1호
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• pp.98-105
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• 2022

Objectives: Low back pain (LBP) is a common chronic condition among sedentary workers that causes long-term productivity loss. This study aimed to identify the relationships of individual and occupational factors with LBP among Bangladeshi online professionals. Methods: We conducted a cross-sectional study involving 468 full-time online professionals who usually worked in a sitting position. One-month LBP complaints were assessed using a musculoskeletal subscale of subjective health complaints. The chi-square test was used to measure associations between categorical predictors and LBP, and multivariable logistic regression was conducted to identify the variables significantly associated with LBP. Results: LBP within the last month was reported by 65.6% of participants. Multivariable logistic regression analysis indicated that age >30 years (adjusted odds ratio [aOR], 0.40; 95% confidence interval [CI], 0.23 to 0.70) and being married (aOR, 0.59; 95% CI, 0.36 to 0.97) had significant negative associations with LBP. Significant positive associations were found for spending >50 hours weekly on average working in a sitting position (aOR, 1.61; 95% CI, 1.05 to 2.49), being overweight and obese (aOR, 1.87; 95% CI, 1.16 to 2.99), sleeping on a soft mattress (aOR, 2.01; 95% CI, 1.06 to 3.80), and ex-smoking status (aOR, 3.33; 95% CI, 1.41 to 7.87). Conclusions: A high prevalence of LBP was found among full-time online professionals. Long working hours in a sitting position showed a significant association with developing LBP. Smoking history, body mass index, and sleeping arrangements should also be considered while considering solutions for LBP prevalence among online professionals.

• Composites Research
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• 제19권1호
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• pp.15-21
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• 2006

It is very difficult to make complex 3 dimensional curved-shape composite laminates using the advanced unidirectional composite prepregs. This study shows development process of subscale composite parabolic antenna reflector using unidirectional AS4/PEEK prepreg tapes. The AS4/PEEK thermoplastic composite materials are known to have good thermal and chemical stabilities in addition to their high specific strength and modulus. Various lamination methods were investigated through finite element analyses to make up the laminate design of the reflector. The automated fiber placement method was used to fabricate the reflector. The thermal expansion test using full-bridge strain gage circuits was done to verity the performance of the composite product.

• Korean Journal of Psychosomatic Medicine
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• 제20권1호
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• pp.50-58
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• 2012

Objectives : This study examined the selective deficits of executive function in patients with mild traumatic brain injury that in normal range of general intelligence level and aimed to analysis of the correlation between K-WAIS result and executive function. Methods : 59 subjects were included in this study, who were diagnosed as mild traumatic brain injury(MTBI) and they have visited in neuropsychiatric department of Wonkwang University Hospital during from March, 2005 to September, 2010. For measurement of general intelligence quotient, the Korean-Wechsler Adults Intelligence Scale(K-WAIS) was administered and for measurement of executive intelligence quotient(EIQ), Executive Intelligence Test(EXIT) was administered. Results : Of patients, 50.8% included at abnormal EIQ group. The patients of abnormal EIQ showed poorer full scale IQ(FIQ), performance IQ(PIQ) and in subscale that picture arrangement, digit symbol, digit span, block design, object assembly and comprehension were significantly different. In terms of relationships between K-WAIS and EIQ, FIQ and PIQ have positive correlation with EIQ. And in subscale, picture arrangement, digit symbol, digit span, block design, object assembly and comprehension show positive correlation with EIQ. Conclusion : This study suggest that MTBI patients with have normal range of general intelligence level may have deficit of executive function is common. The decline of FIQ, PIQ and some subscales of K-WAIS may suggest executive dysfunction in MTBI patients.