• Journal of the Korean Society of School Health
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• v.32 no.2
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• pp.105-115
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• 2019

Purpose: The purpose of this study was to compare the mental health factors related to health risk behaviors between multicultural and monocultural adolescents. Methods: The study subjects were selected from the 2018 Korea Youth Risk Behavior Web-Based Survey Dataset. A total of 60,040 multicultural and monocultural adolescents were included in the analysis. A $x^2$ test and logistic regression were conducted, using SPSS 18.0, to compare the general characteristics, mental health, and health risk behaviors of the multicultural and monocultural adolescents. This process involved a complex sample design. Results: There was a significant difference in the rates of suicidal behaviors. Multicultural adolescents showed a significantly higher rate of suicidal ideation (8.6% vs. 8.5%, p=.004), suicidal plan (3.2% vs. 2.4%, p=.004), and suicidal attempt (5.0% vs 3.1%, p=.04) than monocultural adolescents. Perceived stress had a significant impact only on monocultural adolescents. Monocultural adolescents with high levels of perceived stress were at a greater risk of drinking (high stress=reference; low stress OR=0.91, p=.025) and smoking (high stress=reference; low stress OR=0.90, p=.029) than those with low stress. Multicultural adolescents who had made suicide attempts were at a higher risk of drinking (multicultural OR=7.879, p<.001; monocultural OR=2.481, p<.001) and smoking (multicultural OR=4.011, p=.015; monocultural OR=2.800, p<.001) than monocultural adolescents. Conclusion: To implement an effective smoking and drinking prevention program, it is necessary to consider how we can reduce the risk factors. Stress management is important for monocultural adolescents and a proactive suicide-screening program and a suicide prevention program should be included in the program for both multicultural and monocultural adolescents.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.39 no.1
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• pp.1-12
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• 2019

This study defined abnormal behaviors such as bending deformations or buckling behaviors occurred in high strength steel pipe strut system, and carried out a full-scale bending test for different connection types. A parametric study was carried out to gain an insight about structural performances considering abnormal behavior effects in high strength steel pipe strut system. Five abnormal behaviors were considered as undesirable deflections of strut structures, which are basic load combination, excessive excavation situations, impact loading effects, additional overburden loads, load combinations, and strut lengths. Subsequent simulation results present various influences of parameters on structural performances of the strut system. Based on the results, we propose methods to prevent unusual behaviors of pipe-type strut structures made of high strength steels.

• Progress in Superconductivity and Cryogenics
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• v.21 no.1
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• pp.31-35
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• 2019

The lumped-parameter circuit model for a no- insulation (NI) high temperature superconductor (HTS) magnet has been well understood after many experimental and analytic studies over a decade. It successfully explains the non-linear charging behaviors of NI magnets. Yet, recently, multiple groups reported that the post-quench electromechanical behaviors of an NI HTS magnet may not be well explained by the lumped circuit model. The characteristic resistance of an NI magnet is one of the key parameters to characterize the so-called "NI behaviors" of an NI magnet and recently a few groups reported a potential that the characteristic resistance of an NI magnet may substantially vary during a quench. This paper deals with this issue, the increment of contact resistance of the no-insulation (NI) REBCO magnet during a quench and its impact on the post-quench behaviors. A 7 T 78 mm NI REBCO magnet that was previously built by the MIT Francis Bitter Magnet Laboratory was chosen for our simulation to investigate the increment of contact resistance to better duplicate the post-quench coil voltages in the simulation. The simulation results showed that using the contact resistance value measured in the liquid nitrogen test, the magnitude of the current through the coil must be much greater than the critical current. This indicates that the value of the contact resistance should increase sharply after the quench occurs, depending on the lumped circuit model.

• Journal of the Korean Society of School Health
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• v.34 no.2
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• pp.115-122
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• 2021

Purpose: The purpose of this descriptive research is to identify how stress from Covid-19, health beliefs, and social support of college students affect health prevention. Methods: The subjects of the study were 128 university students, excluding health major students, at one university in D City. The survey was conducted from August 1 to 31, 2020. The survey questionnaire consists of 8 items on stress from COVID-19, 12 items adapted from a health belief measurement tool, 12 items from a social support measurement tool, and 11 items adapted from a tool that measures health preventive behaviors. The collected data were analyzed using the hierarchical multiple regression analysis method with SPSS 26.0. Results: In model 1, stress from COVID-19 was statistically significant (β=-.403, p=.003). Model 2 added four health belief factors into Model 1. Stress (β=-.419, p<.001), perceived severity (β=-.193, p=.030), and perceived barriers (β=-.182, p=.009) were statistically significant. In model 3, stress (β=-.413, p<.001), perceived barriers (β=-.147, p=.034), and social support (β=.194, p=.011) were statistically significant. The regression equation was significant (F=15.395, p=<.001) and the model's explanatory power was 53.1%. Conclusion: The results show that when college students had a high degree of health beliefs about COVID-19, the degree of health preventive behaviors was proportionally high. To make them practice preventive health behaviors, it is necessary to develop infection control education programs to improve health beliefs.

• Journal of Convergence for Information Technology
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• v.12 no.3
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• pp.66-74
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• 2022

This study identified the impact of information literacy, risk perception, crisis communication on preventive behaviors related to COVID-19 among nursing students. Data were collected from 187 nursing students from 25 June 2020 to 3 July 2020, and analyzed using the SPSS/WIN 26.0 program. As a result of regression analysis, the factors influencing prevention behaviors were crisis communication(β=0.30, p<.001), information literacy(β=0.29, p<.001), and risk perception(β=0.19, p=.004). The explanatory power of the model was 27%. This study suggests that the focus should be on improving the activating crisis communication process among individual, family and society, increasing information literacy and risk perception on crisis when developing program to improve COVID-19 preventive behaviors of nursing students experiencing clinical practice.

• Korean Journal of Community Nutrition
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• v.28 no.3
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• pp.206-219
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• 2023

Objectives: Screen time refers to the time spent using screen media, such as televisions, smartphones, computers, or tablets. Excessive exposure to screen media has been reported to negatively impact young children's health and development, including overweight, short sleep duration, and language delays. This study examined the association of screen time and mealtime media use with dietary behaviors among preschool children. Methods: A cross-sectional survey was conducted on parents of children aged three to five years using the online questionnaires of the Nutrition Quotient for Preschoolers (NQ-P) and the Dietary Screening Test (DST). Data from 261 children's parents were analyzed. Results: Of the 261 children, 96.9% used screen media, 55.6% used screen media for two hours or more daily, and 30.7% were exposed to screen media during meals. The NQ-P scores were significantly lower in the children with longer screen time and mealtime media use. Children who used screen media for two hours or more and those exposed to screen media during meals consumed kimchi less frequently and confectionery and sugar-sweetened beverages more frequently than children who used less than two hours and were not exposed to screen media during meals. In addition, they were more likely to be picky about food, refuse to eat, and less likely to feed themselves than children with shorter screen time and no mealtime media use. Conclusions: This study reported an association between unhealthy dietary behaviors, feeding difficulties, and screen time and mealtime media use among preschool children. Further research should explore effective strategies for reducing children's screen time.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.6
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• pp.399-407
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• 2020

The paper examines social entrepreneurial intention through outcome expectations. The proposed model incorporates outcome expectations from social cognitive career theory and theory of planned behaviors. The study also introduces a scale for outcome expectations in social entrepreneurship, including solving social problems, innovation, family tradition of social involvement, meaning in life, prestige and social recognition, competitive and favorite job and wealth. A survey of 279 students was conducted through face-to-face structured interviews. The confirm factor analysis and technique of structural equation modeling were used to explore relationships among latent constructs. Research results show that the outcomes impact only through three determinants of theory of planned behavior and do not have significant impact to social entrepreneurial intention. It suggests that outcome expectations may be a flexible factor. Individual outcome expectations can shift to motivations when facing favorable conditions such as family support, government support, etc. The findings suggest that the ability to predict social entrepreneurial intention of attitude toward behavior, subjective norms, and perceived behavioral control. The proposed model in this study contributes importantly to the emerging literature on entrepreneurial intention, particularly to social entrepreneurial intention. This study is also the first quantitative study to measure the impact of outcome expectations on social entrepreneurial intention.

• Journal of Korea Foundry Society
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• v.34 no.1
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• pp.6-13
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• 2014

The mechanical properties of low-pressure die cast (LPDC) A356-T6 automotive road wheels are evaluated and correlated with their corresponding microstructures. In this study, two types of alloy wheels processed using different LPDC gating system are investigated. The yield stress, tensile stress, and elongation values tested at room temperature are correlated with the secondary dendrite arm spacing (SDAS) with respect to the gating system, and are also compared with similar studies. The SDAS and precipitates are examined using optical microscopy, scanning electron microscopy (SEM) and energy-dispersive spectroscopy. The phase information is also investigated using X-ray diffraction. Charpy impact tests are also performed from $-100^{\circ}C$ to $200^{\circ}C$, and the fracture surfaces are examined using SEM. The impact energy is demonstrated to increase with increasing temperatures without exhibiting specific transition behaviors as in other nonferrous alloys. The fracture toughness is also evaluated using three point bend test with single-edged bend specimens. The obtained fracture toughness values are in good agreement with those in similar studies.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.1004-1007
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• 2001

This paper presents the experimental results to verify the environmental consciousness with economic balances due to cutting fluid behaviors, effectiveness in machining process. Even though cutting fluid improves the machined part quality through the cooling and lubracating effects, its environmental impact is also increased according to the cutting fluid usage. Because cutting fluid are used by experience than science on shop floors, its environmental impact are more serious to human health hazard, shop floor environments. In this study a few cutting parameters are adopted as the machinability index (i.e. ; tool wear and surface roughness), and aerosol mist diffusion rate of cutting fluid as the environment consciousness index. These indeces are analyzed quantitatively via a few experiements. The results of this study can be facilitate the optimization of cutting fluid usage in achieving a balanced environmental consciousness consideration with economic view.

• Nuclear Engineering and Technology
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• v.52 no.8
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• pp.1714-1723
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• 2020

This study aims at characterizing the rheological properties of uranium oxide powders for nuclear fuel pellets manufacturing. The flowability of these powders must be compatible with a reproducible filling of press molds. The particle size distribution is known to have an impact on the rheological properties and fine particles (<100 ㎛) are suspected to have a detrimental effect. In this study, the impact of the particle size distribution on the rheological properties of UO₂ powders was quantified, focusing on the influence of fine particles. Two complementary approaches were used. The first approach involved characterizing the powder in a static state: density, compressibility and shear test measurements were used to understand the behavior of the powder when it is transitioned from a static to a dynamic state (i.e., incipient flow conditions). The second approach involved characterizing the behavior of the powder in a dynamic state. Two zones, corresponding to two characteristic behaviors, were demonstrated for both types of measurements. The obtained results showed the amount of fines should be kept below 10 % wt to ensure a robust mold filling operation (i.e., constant mass and production rate).