• Journal of Digital Convergence
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• v.16 no.12
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• pp.571-577
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• 2018

Bicycle riders complain of many inconveniences when wearing glasses, sunglasses and masks. The disposable fine dust mask has been developed to resolve such inconveniences of bicycle riders. The scope of research is limited to the fiber which generates one-time static electricity and the shape of the mask due to the characteristic of fine dust mask. The purpose is to design and make the fine dust mask with a simple production process. The new disposable fine dust mask has secured enough space of the mask in front of the mouth by longitudinal folding and minimized stuffiness by maintaining the shape of the folded part to prevent touching the mouth even by heavy breathing. The streamlined sponge is attached at the part of nose support and the area of the cheek has been expanded to be about 2.5cm wider than ordinary masks to improve tight seal at the side. In addition, a new disposable fine dust scarf mask has been developed to block ultraviolet rays for the face and neck while filtering fine dust with the tight fine dust mask.

• Membrane Journal
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• v.29 no.3
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• pp.140-146
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• 2019

In this study, a selective layer of poly styrene sulfonic acid (PSSA) and polyethyleneimine (PEI) was formed by layer-by-layer method onto a porous polyacrylonitrile (PAN) hollow fiber membrane as the suppoter membrane. The salting out method was used by adding Mg salt to the coating solution. Several experimental conditions of the ionic strength, polymer concentration, and coating time were investigated, and the flux and rejection were measured at the operating pressure of 2 atm for 100 mg/L of NaCl, $MgCl_2$, and $CaSO_4$ as the feed solution. The membranes coated with PSSA 20,000 ppm, coating time 3 minutes, ionic strength 1.0, PEI 30,000 ppm, coating time 1 minute, and ionic strength 0.1 were observed the best. In the 100 ppm NaCl, $MgCl_2$, and $CaSO_4$ feed solutions, the flux of 20.4, 19.4, and 18.7 LMH, and the rejection of 67, 90, and 66.6%, respectively.

• Composites Research
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• v.32 no.4
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• pp.185-190
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• 2019

This work investigates the elastic buckling characteristics of laminated composite trapezoidal corrugated plates with simply supported edges using the analytical method. In the analysis, three types of in-plane loading conditions: uniaxial, biaxial and shear loads are considered. Because it is very difficult to determine the mechanical behavior of 3-dimensional corrugated structures analytically, the equivalent homogenization model is adapted to investigate the overall mechanical behavior of corrugated plates. The corrugated element is homogenized as an orthotropic material. The previous formulae for bending rigidities of corrugated plate are adapted in this paper. The comparisons of the proposed analytical results with those of FEA based on the shell element are made to verify the proposed analytical method. In the comparison study both the critical buckling loads and the buckling mode shapes are presented. Some numerical results are presented to check the effect of the geometric properties.

• Research in Community and Public Health Nursing
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• v.30 no.3
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• pp.377-389
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• 2019

Purpose: Group-based interventions help the members of the parent group work together to share their parenting stress, provide opportunities for them to support each other emotionally and informatively, and allow them to achieve what they want to accomplish. The purpose of this study is to investigate and synthesize the outcome of a parenting support program for infant and toddler parents. Methods: Published randomized control trials were identified through Ovid-Medline, Embase and CINAHL DB. Eligible studies include articles published between 2008 and 2018 in English in the randomized controlled trial design in which parenting support programs were implemented for infant and toddler parents group. Results: A total of 11 studies was selected for this review. These programs reported large level of effect size for parenting, and middle level effect size for parent's psycho-social outcomes and child development. There were many programs conducted for parents with infants between 13 and 24 months, and the frequency of programs provided for 2 hours a week was high with 9 to 12 sessions. Most programs were facilitated by trained professionals including nurses and social workers except two programs led by lay persons. Conclusion: This review demonstrates that group-based parenting support programs have positive effects on parenting, parent's psychosocial health and infant development. To disseminate the effective group-based parenting support programs, further research is needed to confirm the long term effect and develop nurse's role as a group facilitator.

• Convergence Security Journal
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• v.18 no.4
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• pp.45-52
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• 2018

As the era of the 4th Industrial Revolution has progressed and the information and communication technologies have developed dramatically, the cyber threats will gradually become more intelligent and sophisticated. Therefore, in order to take systematic and prompt action in case of an accident while preparing measures against the threat, the role of intelligence agency is important. However, Korea is having difficulty in responding to the threats due to the lack of support for the national cybersecurity bill or the amendment bill of the National Intelligence Service. In this paper, I examine the cybersecurity function of the intelligence agency, the recent debate trends, and implications for the role of intelligence agency in our current situation. And then I intend to suggest some measures such as concentration on information gathering and analysis, enhancement of cyber threat prediction and response capacity, and strengthening of legal basis as a way to establish the role of intelligence agency for reinforcement of cybersecurity performance system.

• Journal of Hospice and Palliative Care
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• v.22 no.2
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• pp.49-66
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• 2019

Along with the advances in medical technology and the economic development, more terminally ill patients are receiving hospice and palliative care services. Moreover, hospice and palliative care clinicians have been showing considerable interest in studies that aim to improve the quality of said care for patients and their families. Meanwhile, after the government has strengthened its policy to protect research participants, the institutional review boards (IRBs) are more closely examining various ethical issues related to patients' vulnerability when reviewing protocols for hospice and palliative care research. However, terminally ill patients should be provided with guaranteed qualities of hospice and palliative care to improve and maintain their quality of life. To that end, support should be provided for efforts to conduct ethical and safe studies with hospice and palliative care patients. Thus, this review paper proposes ethical guidelines for hospice and palliative care research. The guidelines could be appropriately used as a reference for researchers who should prepare for ethically safe and scientifically valued research protocols and the IRBs that will review the protocols.

• Tribology and Lubricants
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• v.35 no.2
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• pp.123-131
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• 2019

This study characterizes the coastdown performances of two small electric motors supported on high-speed ball bearings (BBs) and gas foil bearings (GFBs), and it predicts their acceleration performances. The two motors have identical permanent magnetic rotors and mating stators. However, the shaft of the GFBs has a larger mass and polar/transverse moments of inertia than that of the BBs. Motor coastdown tests demonstrate that the rotor speed decreases linearly with the BBs and nonlinearly with the GFBs. A simple model for the BBs predicts a constant drag torque and linear decay of speed with time. The test data validate the model predictions. For the GFBs, the hydrodynamic lubrication model predictions reveal that the drag torque increases linearly with speed, and the speed decreases exponentially with time. The predictions agree very well with the test data in the speed range of 100-30 krpm. The boundary lubrication model predicts a constant drag torque and linear decay of speed with time. The predictions agree well with the test data below 15 krpm. Mixed lubrication occurs in the speed range of 30-15 krpm. Rotor acceleration performances are predicted based on the characteristics of deceleration performances. The GFBs require more time to reach 100,000 krpm than the BBs because of their larger shaft polar moment of inertia. However, predictions for the assumed identical polar moment of inertia reveal that the GFBs have a nearly identical acceleration performance to that of the BBs with a motor torque greater than $0.03N{\cdot}m$.

• Tribology and Lubricants
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• v.35 no.2
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• pp.114-122
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• 2019

High-speed rotating machinery requires low cost and reliable bearing elements with low friction, stable rotordynamic characteristics, and a simple design. This study experimentally evaluates the effects of bearing-support elements on the vibrational characteristics of a small-sized, high-speed permanent magnetic motor. A series of coast down tests from 100 krpm characterize the vibrational behaviors, rotor displacement, and housing acceleration of motors supported by ball bearings, ball bearings with a metal mesh damper, and gas foil bearings, respectively. Two eddy-current sensors installed in the horizontal and vertical directions measure the displacement of the rotor at its front nut, and a 3-axis accelerometer attached to the motor housing measures the housing acceleration. The test results reveal that synchronous (1X) vibration components most significantly affect the rotor displacement and housing acceleration, independent of the bearing-support elements. The motor supported by the deep-groove ball bearings results in the largest rotor vibrations increasing with speed; this is due to the absence of a damping mechanism. Additionally, the metal mesh damper effectively reduces the rotor displacement, housing acceleration, and sound-pressure level in the high-speed region (i.e., above 40 krpm), thus implying its substantial damping performance when installed on the outer race of the ball bearing. Lastly, the gas foil bearing supported motor yields the smallest rotor displacement, housing acceleration, and lowest sound-pressure level because of its hydrodynamic airborne operation, which does not require rolling elements that may cause mechanical friction and vibrations.

• Research in Community and Public Health Nursing
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• v.30 no.2
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• pp.217-225
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• 2019

Purpose: The purpose of this study is to assess socio-demographic, disaster-related, physical health-related, psychological, and social factors that may adversely affect disaster victims' QoL (Quality of Life). Methods: A cross sectional study was designed by using the secondary data. From the 3rd Disaster Victims Panel Survey (2012~2017), a total of 1,659 data were analyzed by using descriptive statistics including frequency, percentage, t-test, ANOVA, and multivariate linear regression. Results: Older people with lower health status lacking financial resources prior to a disaster were more at risk of low levels of QoL. Lower levels of perceived health status, resilience, and QoL were reported by disaster exposed individuals, while their depression was higher than the depression in the control group of disaster unexposed ones. Resilience, social and material supports were positively associated with QoL whereas depression and PTSD (Post-Traumatic Stress Disorders) were negatively associated. Conclusion: These findings suggest that psychological symptoms and loss due to disasters can have adverse impacts on the QoL of disaster victims in accordance with their prior socio-demographic background. They also indicate that targeted post-disaster community nursing intervention should be considered a means of increased social support as well as physical and mental health care for disaster victims.

• Journal of Korean Academy of Nursing
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• v.49 no.3
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• pp.298-306
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• 2019

Purpose: This study aimed to examine the levels of perceived self-management support, self-efficacy for self-management, and health-related quality of life (HRQoL) in cancer survivors, and to identify the mediating effect of self-efficacy in the relationship between perceived self-management support and HRQoL. Methods: This study used a descriptive correlational design. Two hundred and four cancer survivors who had completed treatment participated in the study. Measurements included the Patient Assessment of Chronic Illness Care Scale, the Korean version of the Cancer Survivors' Self-Efficacy Scale, and the Medical Outcomes Study Short Form-36. Data were analyzed using descriptive statistics, Pearson's correlation coefficient analysis, and multiple regression analysis using Baron and Kenny's method for mediation. Results: The mean score for perceived self-management support was 3.35 out of 5 points, self-efficacy was 7.26 out of 10 points, and HRQoL was 65.90 out of 100 points. Perceived self-management support was significantly positively correlated with self-efficacy (r=.29, p<.001) and HRQoL (r=.27, p<.001). Self-efficacy was also significantly correlated with HRQoL (r=.59, p<.001). Furthermore, self-efficacy (${\beta}=.55$, p<.001) had a complete mediating effect on the relationship between perceived self-management support and HRQoL (Z=3.88, p<.001). Conclusion: The impact of perceived self-management support on HRQoL in cancer survivors was mediated by self-efficacy for self-management. This suggests that strategies for enhancing self-efficacy in cancer survivors should be considered when developing self-management interventions for improving their HRQoL.