• Journal of Ocean Engineering and Technology
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• v.33 no.2
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• pp.131-138
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• 2019

This study focused on the roll motion characteristics of a two-dimensional (2D) rectangular floating structure under regular beam sea conditions. An experiment was conducted in a 2D wave tank for a roll free decay test in calm water and the roll motion in a range of regular waves with and without heave motion to investigate the motion response and heave influence on the roll motion. A numerical study was carried out using Reynolds-averaged Navier Stokes (RANS)-based CFD simulations. A grid convergence test was conducted to accurately capture the wave condition on the free surface based on the overset mesh and wave forcing method. It was found in the roll free decay test that the numerical results agreed well with the experimental results for the natural roll period and roll damping coefficient. It was also observed that the heave motion had an impact on the roll motion, and the responses of the heave and roll motion from the CFD simulations were in reasonable agreement with those from the experiment.

• Journal of Hospice and Palliative Care
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• v.21 no.4
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• pp.115-123
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• 2018

Purpose: The purpose of this study was to identify how nursing students' awareness of biomedical ethics and ethical values affect their attitudes towards a do-not-resuscitate (DNR) order. Methods: This cross-sectional correlation study was conducted with 275 nursing students enrolled at two universities in North Chungcheong Province and North Gyeongsang Province of South Korea. Data were collected in April 2017 using a self-reported questionnaire. Data were analyzed using descriptive statistics, t-test, ANOVA, Pearson correlation coefficient and stepwise multiple regression with the SPSS/WIN 23.0 program. Results: The students' attitudes towards DNR were positively correlated with attitudes that seek ethical values but negatively correlated with their biomedical ethics awareness. The explained variance for attitudes towards DNR was 20%, which was significant (F=13.01, P<0.001). Conclusion: These findings suggest that nursing students' biomedical ethics awareness and ethical values were associated with their attitudes towards DNR. Curriculum organization and various educational programs should be developed and applied to help nursing students develop ethical values and awareness of biomedical ethics.

• The Journal of the Korea Contents Association
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• v.19 no.6
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• pp.387-401
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• 2019

The aim of this study is to investigate the effects of income inequality caused by capital and wage incomes under globalized economic system in Korea. Empirical evidences which are obtained by cointegration methodology reveal that the effects resulted from capital and wage incomes to income inequality are alternative between short-run and long-run. And, the wage income has stronger impact on income inequality than the capital income. This might be occured as a result of that inbound foreign capital seems not to contribute to economic activity in real sector. It also has to be mentioned that the income inequality is negatively influenced by international trade in the short run and in the long run as well. To this end, it would be concluded that well-organized distribution system for wage income should be established, accordingly. And, forward and backward linkages in exporting industry have to be re-evaluated in order to improve income inequality in Korea.

• The Journal of Information Systems
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• v.28 no.3
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• pp.1-23
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• 2019

Purpose This study examines the role of corporate image and privacy concerns in intention to use of online travel services using data from Vietnam. Design/methodology/approach The data collection was implemented to a student sample at the Foreign Trade University in Hanoi, which has a high concentration of young people who are interested in online travel in Vietnam. The paper based questionnaire was directly delivered to the respondents. After sorting to eliminate unfit samples, the number of responses was 541, which exceeds 500, the minimum number typically required. To test the hypotheses, we applied structural equation modeling (SEM) and Confirmatory Factor Analysis (CFA) was used to evaluate the reliability and validity of constructs in the model. We also used direct, indirect and total effect coefficient to evaluate the total impact of factors on the intention to use online services. Findings This study found that corporate image is positively associated to intention to use online services. It found a link between corporate image and privacy concerns, which suggests another way for firms to address their customers' privacy concerns; corporate image, which has received great attention in traditional offline sales channels, but not in online services, should receive higher attention in IS research. Online travel businesses, besides increasing ease of use, perceived usefulness and trust in their services, should focus on build a reliable corporate image, which can not only promote the service use but also help to eliminate users' the privacy concerns.

• Wind and Structures
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• v.29 no.4
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• pp.247-270
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• 2019

Wind-resistant design of existing cooling tower structures overlooks the impacts of rainfall. However, rainstorm will influence aerodynamic force on the tower surface directly. Under this circumstance, the structural response of the super-large cooling tower (SLCT) will become more complicated, and then the stability and safety of SLCT will receive significant impact. In this paper, surrounding wind fields of the world highest (210 m) cooling tower in Northwest China underthree typical wind velocities were simulated based on the wind-rain two-way coupling algorithm. Next, wind-rain coupling synchronous iteration calculations were conducted under 9 different wind speed-rainfall intensity combinations by adding the discrete phase model (DPM). On this basis, the influencing laws of different wind speed-rainfall intensity combinations on wind-driving rain, adhesive force of rain drops and rain pressure coefficients were discussed. The acting mechanisms of speed line, turbulence energy strength as well as running speed and trajectory of rain drops on structural surface in the wind-rain coupling field were disclosed. Moreover, the fitting formula of wind-rain coupling equivalent pressure coefficient of the cooling tower was proposed. A systematic contrast analysis on its 3D distribution pattern was carried out. Finally, coupling model of SLCT under different working conditions was constructed by combining the finite element method. Structural response, buckling stability and local stability of SLCT under different wind velocities and wind speed-rainfall intensity combinations were compared and analyzed. Major research conclusions can provide references to determine loads of similar SLCT accurately under extremely complicated working conditions.

• Advances in nano research
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• v.7 no.3
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• pp.191-208
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• 2019

In the present work the dynamic analysis of the functionally graded rectangular nanoplates is studied. The theory of nonlocal elasticity based on the quasi 3D high shear deformation theory (quasi 3D HSDT) has been employed to determine the natural frequencies of the nanosize FG plate. In HSDT a cubic function is employed in terms of thickness coordinate to introduce the influence of transverse shear deformation and stretching thickness. The theory of nonlocal elasticity is utilized to examine the impact of the small scale on the natural frequency of the FG rectangular nanoplate. The equations of motion are deduced by implementing Hamilton's principle. To demonstrate the accuracy of the proposed method, the calculated results in specific cases are compared and examined with available results in the literature and a good agreement is observed. Finally, the influence of the various parameters such as the nonlocal coefficient, the material indexes, the aspect ratio, and the thickness to length ratio on the dynamic properties of the FG nanoplates is illustrated and discussed in detail.

• Nuclear Engineering and Technology
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• v.51 no.6
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• pp.1540-1553
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• 2019

A nuclear power plant (NPP) is a highly complex system-of-systems as manifested through its internal systems interdependence. The negative impact of such interdependence was demonstrated through the 2011 Fukushima Daiichi nuclear disaster. As such, there is a critical need for new strategies to overcome the limitations of current risk assessment techniques (e.g. the use of static event and fault tree schemes), particularly through simulation of the nonlinear dynamic feedback mechanisms between the different NPP systems/components. As the first and key step towards developing an integrated NPP dynamic probabilistic risk assessment platform that can account for such feedback mechanisms, the current study adopts a system dynamics simulation approach to model the thermal dynamic processes in: the reactor core; the secondary coolant system; and the pressurized water reactor. The reactor core and secondary coolant system parameters used to develop system dynamics models are based on those of the Palo Verde Nuclear Generating Station. These three system dynamics models are subsequently validated, using results from published work, under different system perturbations including the change in reactivity, the steam valve coefficient, the primary coolant flow, and others. Moving forward, the developed system dynamics models can be integrated with other interacting processes within a NPP to form the basis of a dynamic system-level (systemic) risk assessment tool.

• Journal of the Microelectronics and Packaging Society
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• v.25 no.4
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• pp.89-93
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• 2018

Ceramic substrates applied to power modules of electric vehicles are required to have properties of high thermal conductivity, high electrical insulation, low thermal expansion coefficient and resistance to abrupt temperature change due to high power applied by driving power. Aluminum nitride and silicon nitride, which are applied to heat dissipation, are considered as materials meeting their needs. Therefore, in this paper, the properties of aluminum nitride and silicon nitride as radiator plate materials were compared through a commercial analysis program. As a result, when the process of applying heat of the same condition to aluminum nitride was implemented by simulation, the silicon nitride exhibited superior impact resistance and stress resistance due to less stress and warping. In terms of thermal conductivity, aluminum nitride has superior properties as a heat dissipation material, but silicon nitride is more dominant in terms of reliability.

• Journal of Digital Convergence
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• v.17 no.1
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• pp.55-62
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• 2019

This study analyzed the relationship between housing price, purchase price, Gini coefficient, interest rate, and the employment, considering that the change in housing price was an important factor influencing macroeconomic variables and income inequality. The panel VAR model was constructed considering the panel data, and the Granger causality, Impulse response and Variance dispersion analysis were performed. As a result, when compared to before and after the global financial crisis, it was shown that the rent price had an effect on income inequality, but in the following period, both the rent price and the selling price affected the income inequality. And that it has a large impact on inequality. In addition, the causality between income inequality and employment rate, interest rate, and tax rate was confirmed. Therefore, it is expected that it will be a desirable policy to mitigate income inequality considering the influence of policy variables for economic activation including government real estate policy.

• 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.