• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.11 no.6
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• pp.774-788
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• 1999

To examine the enhancement mechanism of condensing heat transfer through microfin tube, the condensation experiments with refrigerant HCFC 22 are performed using 4 and 6 kinds of microfin tubes with outer diameter of 9.52mm and 7.0mm, respectively. Used microfin tubes have different shape and number of fins with each other The main heat transfer enhancement mechanism is known to be the enlargement of heat transfer area and turbulence promotion. Together with these main factors, we can find other enhancement factors by the experimental data, which are the overflow of the refrigerant over the microfin and microfin arrangement. The overflow of the refrigerant over the microfin can be analyzed by the geometric shape of the microfin. Microfin tubes having a shape which can give much overflow over the microfin show large condensing heat transfer coefficients. The effect of microfin arrangement is related to the heat transfer resistance of liquid film of refrigerant. The condensing heat transfer coefficients are high for the microfin tube with even distribution of liquid film.

• Journal of Fashion Business
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• v.20 no.4
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• pp.36-49
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• 2016

The objective of this study was to examine the effects of appearance management behaviors on career decision level among female college students. Based on previous studies on appearance management behaviors and career decision level, the items for a questionnaire were developed. For the study, we conducted a questionnaire survey among 292 students from women's university in Seoul. Factor analysis, correlation analysis and multiple regression analysis were performed using SPSS statistics 23. Results of this study are as follows. First, the factor structure of appearance management behavior had three factors: 'fashion & hair,' 'skin & plastic surgery,' and 'body shape.' The reliability and validity of the factor structure were proved. Second, a significant correlation was found between sub-factors in appearance management behaviors. Career decision level showed a significant correlation only with body management factor. Third, the appearance management behavior of female college students was found to have a partially significant effect on career decision level. For higher grade students, fashion & hair factor and body shape factor had positive effects on career decision level. For lower grade students, body shape factor had a positive effect on career decision level while skin & plastic surgery factor had a negative effect on career decision level. Therefore, to increase career decision level, managing appearance through keeping fit body shape is crucial. This study also suggests that as one elevates to a higher grade, the importance of management and keeping interest toward fashion is important.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.9
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• pp.76-83
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• 2021

This study examines the characteristics of spraying conditions based on the change in standoff distance during fine particle spraying while measuring the surface roughness, maximum depth, and maximum width of the sprayed surface. The processing shape of the sprayed surface is analyzed to understand the effects of injection pressure, nozzle diameter, standoff distance, processing shape, processing cycle, processing speed, and injection particles, which are the main factors of fine particle injection processing. Based on the derived characteristics, we attempt to determine the interrelationships of these major factors. The standoff distance is set as a variable factor and a spray machining experiment using a hexagonal shape (from among polygons) instead of square and circular shapes is conducted. Results reveal that research on the characteristics of spraying conditions could be expanded based on changes in the shapes of workpieces.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.563-566
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• 2000

Recently vehicle development trend puts emphasis on cost reduction and performance improvement through weight reduction, and safety security to protect passenger and chassis against external impact. Primary factors effected on vehicle safety are chassis structure, chassis system, and safety equipment like bumper. Research in part of weight reduction is proceeding actively about prohibition of over-design and material through optimal design method. Bumper in these factors is demanded two of all factors, safety security and weight reduction. It is the part that prohibits or reduces a physical impact in low speed crash. Bumper is composed of a few parts but this study exhibits the shape of bumper rail has a role on energy absorption of safety security and weight reduction from structure analysis of bumper rail's variable shape surface.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1992.04a
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• pp.79-83
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• 1992

According to the variation of hydrostatic pressure on the central axis of deformable material, the V-shaped central bursting defect may be created on extrusion or drawing processes. The process factors whichaffect the generation of defects are die semi-angle, reduction ratio of cross-sectional area, friction factor, material properties and so on. The combination of these factors can determine the prossibility of defect creation and the shape of various round holes which have been created inside already. By the rigid plastic finite element method, this paper describes the observations of change in shape of a round hole with process conditions suchas die semi-angle, reduction ratio of cross-sectional area and friction factorat the unsteady state of axi-symmetrical extrusion process when the round hole is alreadyexisted inside the original billet, and also, the effects of process factors are investigated to prevent the possible defects.

• Journal of the Korean Society of Clothing and Textiles
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• v.23 no.8
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• pp.1139-1148
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• 1999

This paper discussed the assessment of hand of denim fabrics finished by enzymatic hydrolysis. The semantic differential scale established using the database collected from university students. Analyzing the subjective rating by common factor analysis with oblimin rotation five factors expressing the hand were induced. Factor one was the surface property related to the surface roughness or softness Factor two was the durability which was related to the compactness and bearing strength Factor three was the sense of weight which was related to the thickness and weight. The moisture related properties and the sense of shape recovery were the forth and fifth factors respectively. the evaluations on the surface property weight and moisture related properties were similar by men and women However the shape recovery and the durability were evaluated differently. Surface and weight related properties were important factors judging the hand of fabrics by both group.

• Transactions of Materials Processing
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• v.32 no.2
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• pp.61-66
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• 2023

The quality of the sheared surface affects the stretch flangeability of steel sheet. The quality of sheared surface is influenced by several process factors such as die clearance, shape of cutting edge, use of counter punch, and shear. In this paper, the influence of these shearing process factors on the stretch flangeability of the HSS (DP980) was analyzed through a shearing and a stretch flangeability test. When the die clearance was 10%, the effect of these shearing process factors on the stretch flangeability was the greatest, and the use of an acute angle blade was found to be more advantageous in the stretch flangeability than a right angle blade. It was found that the stretch flangeability was improved when active bending was applied during shearing.

• Korean Journal of Health Education and Promotion
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• v.19 no.1
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• pp.59-85
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• 2002

The purpose of this study was to examine the health promoting behavior of university students and its related factors. A self-administered questionnaire survey was carried out for 1,031(male, 477, female, 554) students from 7 universities in Taegu from March 10 to April 15 2000. Collected data were analyzed by the $X^2$-test, t-test, ANOV A and structural equation modeling analysis. The results of this study were as follows; Mean score of health promoting behavior of women was higher than mean score of men(p〈0.01). According to the subordinate fields, female students showed significantly higher scores in the fields of stress management, nutrition, personal relations and alcohol-cigarette(p〈0.05). And in male students, the only fields of exercise had meaningfully higher score(p〈0.01). The highest degree of performance was marked in alcohol-cigarette field in female, and interpersonal field in male. In Both male and female students, the lowest field was health responsibility. The mean score of health promoting behavior showed significant differences in intermediating factors such as age, health education and grade in male, and such as grade, pocket money for a month, taking health education, perceived body shape and gastrointestinal symptoms in female(p〈0.05). The mean score of health promoting behavior showed significant differences in cognitive-perceptual factors and cues to action such as perceived health status, perceived benefits, perceived barriers, and health concern of parents in both male and female(p〈0.05). By the results of structural equation modeling analysis in male students, the economic status, gastrointestinal symptoms and perceived body shape as lean had significant direct effects on cognitive-perceptual factors($\mid$T$\mid$〉2.0). Grade and health concern of parents had significant direct effects on health promotion behaviors($\mid$T$\mid$〉2.0). In female students, perceived body shape as lean and perceived body shape as fat had significant direct effects on cognitive-perceptual factors($\mid$T$\mid$〉2.0). Grade, pocket money and health concern of parents had significant direct effects on health promotion behaviors($\mid$T$\mid$〉2.0). On the consideration of above findings, it is recommended that perceived health status and perceived benefits should be raised and perceived barriers should be lowered to increase health promoting behaviors, by means such as institutional approach which can enhance the primary prevention for a disease. In addition, the health policy for improving parents' concern about health as well as university students, through various ways such as health education, consulting, and health program, should be employed.

• The Journal of the Korean dental association
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• v.53 no.2
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• pp.132-142
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• 2015

Purpose : The objective of this research was to investigate an optimization of drill design factors for implant stability and efficacy through comparative evaluation by the cutting time, heat generation and initial stability. Materials and Methods : Three design factors were considered for the purpose of drill design optimization; the number of flute(2 flute, 3 flute), helix angle($15^{\circ}$, $25^{\circ}$) and drill tip shape(straight, 2-phase). Design factors were selected through comparative evaluation by temperature change, cutting time and ISQ value. Results : Heat generation and cutting time are influenced by all design factors(p<0.05). Drill tip shape was the only factors which influenced to the largest initial stability(p<0.05). Conclusion : Drills with 2 flutes, 2-phase formed drill tip, and 25 degrees of helix angle exhibit a better performance than other design.

• Korean Journal of Human Ecology
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• v.13 no.6
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• pp.1023-1029
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• 2004

In the current study, we measured the hands and other representative body items of 223 elementary school girls using Martin Anthropometer and a digital camera so that we would be able to provide information on both size and shape of hands for design of hand-related products. As time goes on, hands get bigger, yet they get thinner at the same time. The data implies that the frame of hands grows, but the skin fat lessens, which could be a determinant factor in the size system of hand-related products. According to the results of a factor analysis on 26 hand items, 5 factors including hand laterality and linearity, fingertip shape, finger breadth, and hand depth, have been extracted. Pearson's correlation showed that most of hand-related factors were strongly associated with other body items. Finger breadth and hand depth, however, were found less related to other body items. The ANOVA test used in testing the difference of hand factors showed, in most items, a difference by ages, but there was no significant differences in fingertip breadth, the third factor, Interestingly, in hand depth, the fifth factor, lower grade girls' hands were thicker than higher grade girls'. This research suggests that the size system of uniformly increasing the size of all hand parts by age groups should be reconsidered and leaves much for improvement.