• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.5
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• pp.86-95
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• 2000

A modified spray impingement model has been developed, which is assessed against experiments for the impinging sprays on the small combustion chamber at various gas pressures. To investigate spray behaviors in the diesel combustion chamber, a transparent constant-volume chamber is made which is similar to the combustion chamber of the real diesel engine. The chamber is pressurized by N2 gas from 0 bar to 20 bar to find the effects of ambient pressures. The behaviors of spray injected into this chamber and dispersed after impingement on the cylinder wall is measured two-dimensionally using laser sheet Mie scattering method. The physical submodels have been properly modified to improve the prediction capability of original KIVA code to describe the spray behaviors after impingement on the curved cylinder wall. In terms of spray dynamics and evolution. numerical results give qualitatively good agreements with experimental data.

• The Journal of Korean Academic Society of Nursing Education
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• v.21 no.4
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• pp.509-517
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• 2015

Purpose: This study examined diabetes knowledge, self-efficacy, and health promoting behaviors, and investigated factors affecting health-promoting behaviors of middle-aged people. Methods: From August to September 2014, a convenience sample of 264 subjects was recruited from B city and G province. The data analysis was done by ${\chi}^2$ test, t-test, Pearson's correlation coefficient, and stepwise multiple regression. Results: Diabetes knowledge was $11.3{\pm}3.63$ in men and $12.7{\pm}3.74$ in women. The average levels of self-efficacy and health promoting behaviors of subjects were similar with other middle-aged individuals. Diabetes knowledge, self-efficacy, and health promoting behaviors had a positive correlation with each other in both men and women. To test the mediating effect of self-efficacy in the relationship between diabetes knowledge and health promoting behaviors, a Sobel test was performed and Z-scores of 3.698(p<.001) in men and 2.748(p=.006) in women were obtained. Conclusion: Diabetes prevention education is recommended for the middle-aged community. When developing diabetes prevention program for middle-aged people, such programs should consider self-efficacy, especially in women.

• Korean Journal of Child Studies
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• v.25 no.4
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• pp.49-70
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• 2004

The sample of this study on sibling relationships consisted of 40 pairs of preschool siblings and their mothers. Results were that elder siblings initiated more behavior, initiated more negative behavior, and responded with more negative or no response to affirmative behavior initiated by the younger siblings. Younger siblings exhibited more responsive behavior, initiated more affirmative behavior, showed more affirmative responses to or imitation of affirmative behavior, and imitation of negative behavior than elder siblings. Male pairs exhibited more physical affirmative interaction than female or male-female pairs. Female pairs exhibited more lingual affirmative interaction than male or male-female pairs. Siblings with similar temperaments showed more boastful or no response to negative behaviors than siblings with differing temperaments. Siblings with differing temperaments exhibited more affirmative behaviors than siblings with similar temperaments.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.190-193
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• 2003

Flexural-torsional behaviors of the typical architectural precast beam sections - inverted tee and rectangular - were compared. The inverted-tee beams were designed with a parking live load - 500kgf/$\textrm{m}^2$ and a market-1,200kgf/$\textrm{m}^2$ according to the currently used typical shape in the domestic market building site. The rectangular beams were also designed as the same bottom dimension and area, and reinforced for similar strength as in the cases of inverted tee beams. Two rectangular and two inverted precast pretensioned concrete beams were tested and analyzed

• Steel and Composite Structures
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• v.29 no.1
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• pp.23-37
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• 2018

In this paper, seismic provisions related to built-up special concentrically braced frames (BSCBFs) are investigated under cyclic loading using non-linear finite element analysis of a single-bay single-story frame. These braces, which contain double angle and double channel brace sections, are considered in two types of single diagonal and X-braced frames. The results of this study show that current seismic provisions such as observing the 0.4 ratio for slenderness ratio of individual elements between stitch connectors are conservative in BSCBFs, and can be increased according to the type of braces. Furthermore, such increments will lead to decreasing or remaining the current middle protected zone requirements of each BSCBFs. Failure results of BSCBFs, which are related to the plastic equivalent strain growth of members and ductility capacity of the models, show that the behaviors of double channel back-to-back diagonal braces are more desirable than those of similar face-to-face ones. Also, for double angle diagonal braces, results show that the failure of back-to-back BSCBFs occurs faster in comparison with face-to-face similar braces. In X-braced frames, cyclic and failure behaviors of built-up face-to-face models are more desirable than similar back-to-back braces in general.

• Natural Product Sciences
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• v.18 no.2
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• pp.67-75
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• 2012

Zizyphi Spinosi Semen (ZSS) have been widely used for the treatment of insomnia in Asia. This experiment was performed to investigate whether methanol extract of ZSS (MEZSS) has hypnotic effects through the ${\gamma}$-amino butyric acid (GABA)ergic systems. MEZSS inhibited the locomotor activity. MEZSS enhanced pentobarbital-induced sleep behaviors. However, MEZSS itself did not induce sleep at higher dose, similar to muscimol. On the other hand, both pentobarbital and MEZSS increased the non rapid eye move (NREM) sleep, especially reducing the -wave electroencephalogram (EEG) activity in REM sleep. MEZSS showed similar effects with muscimol on potentiating chloride influx induced by pentobarbital. MEZSS significantly increased GABAA receptors ${\gamma}$-subunit expression and slightly decreased ${\beta}$-subunit expression in hypothalamus and thalamus, showing that subunit-expression was similar to diazepam. In addition, MEZSS enhanced the expression of glutamic acid decarboxylase (GAD). In conclusion, it is suggested that MEZSS might augment pentobarbital-induced sleep behaviors through the modification of GABAergic systems.

• Research in Community and Public Health Nursing
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• v.28 no.2
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• pp.173-181
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• 2017

Purpose: Early sexual intercourse is associated with poor health outcomes in adolescents. It is known that sexual intercourse coincides with other health risk behaviors such as smoking, drinking, and using drugs. The purpose of this study is to identify the relationships between sexual intercourse and health risk behaviors among Korean and US adolescents using nationally representative data. Methods: Data were collected from the 2011 Korea Youth Risk Behavior Web-based Survey (29,676 students) and 2011 Youth Risk Behavior Surveillance System (10,135 high school students). Logistic regression analysis was performed. Results: In Korea, students who had sexual intercourse accounted for 7.0% in total. Among these, 9.7% were male and 4.2% were female students. In the US, a total of 51.3% students had sexual intercourse, and the proportion of the US male (49.3%) and female (53.4%) students who had sexual intercourse was similar. Korean and US students who experienced sexual intercourse were more likely to smoke, drink alcohol, and use drugs. Conclusion: Since the results of this study show the relationships between sexual intercourse and health risk behaviors, it is necessary to develop comprehensive sex education programs with effective strategies to reduce health risk behaviors in adolescents.

• International Journal of Fluid Machinery and Systems
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• v.9 no.4
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• pp.338-353
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• 2016

Information on the surge behaviors and stall stagnation boundaries for a nine-stage axial flow compressor are summarized on the basis of analytical data in comparison with those for a single-stage one, with attention to the pressure ratio effect. The general trends of the surge loop behaviors of the pressure-mass flow are similar for both compressors including the fact that the subharmonic surges tend to appear very near the stall stagnation boundaries. With respect to the nine-stage compressor, however, the mild loops in the subharmonic surges tend to be very small in size relative to the deep loops, and at the same time, insufficient surge recovery phenomenon, which is a kind of subharmonic surge, appears also far from the stagnation boundary for relatively short delivery flow-paths. The latter is found to be a rear-stage surge caused by unstalling and re-stalling of the rear stages with the front-stages kept in stall in the stalled condition of the whole compressor, which situation is caused by stage-wise mismatching in the bottom pressure levels of the in-stall multi-stage compressor. The fundamental information on the stall stagnation boundaries is given by a group of normalized geometrical parameters including relative delivery flow-path length, relative suction flow-path length, and sectional area-pressure ratio, and by another group of normalized frequency parameters including relative surge frequencies, modified reduced resonance frequencies, and modified reduced surge frequencies. Respective groups of the normalized parameters show very similar tendency of behaviors for the nine-stage compressor and the single-stage compressor. The modified reduced resonance frequency could be the more reasonable parameter suggesting the flow-induced oscillation nature of the surge phenomena. It could give the stall stagnation boundary in a more unified manner than the Greitzer's B parameter.

• Journal of Preventive Medicine and Public Health
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• v.51 no.1
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• pp.6-14
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• 2018

Objectives: To investigate concordance in the health behaviors of women and their partners according to age and to investigate whether there was a stronger correlation between the health behaviors of housewives and those of their partners than between the health behaviors of non-housewives and those of their partners. Methods: We used data obtained from women participants in the 2015 Korea Community Health Survey who were living with their partners. The outcome variables were 4 health behaviors: smoking, drinking, eating salty food, and physical activity. The main independent variables were the partners' corresponding health behaviors. We categorized age into 4 groups (19-29, 30-49, 50-64, and ${\geq}65\;years$) and utilized multivariate logistic regression analysis, stratifying by age group. Another logistic regression analysis was stratified by whether the participant identified as a housewife. Results: Data from 64 971 women older than 18 years of age were analyzed. Of the 4 health behaviors, the risk of smoking (adjusted odds ratio [aOR], 4.65; 95% confidence interval [CI], 3.93 to 5.49) was highest when the participant's partner was also a smoker. Similar results were found for an inactive lifestyle (aOR, 2.56; 95% CI, 2.45 to 2.66), eating salty food (aOR, 2.48; 95% CI, 2.36 to 2.62); and excessive drinking (aOR, 1.89; 95% CI, 1.80 to 1.98). In comparison to non-housewives, housewives had higher odds of eating salty food. Conclusions: The health behaviors of women were positively correlated with those of their partners. The magnitude of the concordance differed by age group.

• Journal of the Korean Society of Clothing and Textiles
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• v.36 no.12
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• pp.1257-1269
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• 2012

The dyeing behaviors of berberine chloride, palmatine chloride hydrate, and Phellodendron bark extract on silk fabric were investigated to evaluate palmatine as another chromophoric substance of Phellodendron bark. The dyeing conditions were composed of combinations of pH (3, 5, 7, 9), temperature (10, 30, 55, $80^{\circ}C$), and time (10, 30, 60 min). The results indicate that palmatine was comparable to berberine in the dyeing behaviors tested for this study and the results were statistically significant. The dye exhaustion and dye uptake of palmatine-CH were slightly lower than berberine-C, which however were not statistically significant. Similar to berberine-C, palmatine-CH favored a pH 7 condition for both dye exhaustion and dye uptake. However, palmatine-CH favors a higher dyeing temperature and longer dyeing time than berberine-C for superior dyeing results.