• Structural Engineering and Mechanics
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• v.89 no.1
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• pp.1-11
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• 2024

This article introduces a novel analytical model for examining the impact of porosity on shear correction factors (SCFs) in functionally graded porous beams (FGPB). The study employs uneven and logarithmic-uneven modified porosity-dependent power-law functions, which are distributed throughout the thickness of the FGP beams. Additionally, a modified exponential-power law function is used to estimate the effective mechanical properties of functionally graded porous beams. The correction factor plays a crucial role in this analysis as it appears as a coefficient in the expression for the transverse shear stress resultant. It compensatesfor the assumption that the shear strain is uniform across the depth of the cross-section. By applying the energy equivalence principle, a general expression for static SCFs in FGPBs is derived. The resulting expression aligns with the findings obtained from Reissner's analysis, particularly when transitioning from the two-dimensional case (plate) to the one-dimensional case (beam). The article presents a convenient algebraic form of the solution and provides new case studies to demonstrate the practicality of the proposed formulation. Numerical results are also presented to illustrate the influence of porosity distribution on SCFs for different types of FGPBs. Furthermore, the article validates the numerical consistency of the mechanical property changesin FG beams without porosity and the SCF by comparing them with available results.

• The Journal of Korean Academic Society of Nursing Education
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• v.30 no.2
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• pp.113-123
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• 2024

Purpose: This study aimed to examine the mediating effect of learning immersion in clinical simulations on the relationship between nursing student learning motivation and achievement in clinical simulation. Methods: This study was conducted using a cross-sectional survey with 184 nursing students from two universities who participated in clinical simulation between September and December 2022. The participants completed a self-administered questionnaire, and the collected data were analyzed using independent an independent t-test, Mann-Whitney U-test, one-way ANOVA, Pearson's correlation coefficient, and multiple regression analysis to identify the mediating effects of learning immersion on the relationship between nursing student learning motivation and achievement. Results: Among the subvariables of nursing student learning motivation, task value and self-efficacy for learning and performance had a significant effect on learning immersion (respectively, β=.36, p=.001; β=.31, p<.001) and learning achievement (respectively, β=.48, p<.001; β=.38, p<.001). With the input of learning motivation variables, the direct effect of learning immersion on learning achievement was significant (β=.20, p=.003), and the effects of learning motivation and task value and self-efficacy on learning achievement was reduced after controlling for learning immersion, which is a mediating variable (respectively, β=.41, p<.001; β=.32, p<.001). The bootstrapping test to confirm the mediating effect of learning immersion was also significant (task value 95% confidence interval [95% CI], 0.02~0.20; self-efficacy 95% CI, 0.01~0.12). Conclusion: The results of this study suggest that simulation educators should consider learners' motivation and immersion when organizing and operating clinical simulations.

• Journal of radiological science and technology
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• v.47 no.3
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• pp.175-182
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• 2024

Advanced modeled iterative reconstruction (ADMIRE) represents a repetitive reconstruction method that can adjust strength and kernel, each of which are known to affect computed tomography (CT) image quality. The aim of this study was to quantitatively analyze the noise and spatial resolution of CT images according to ADMIRE control factors. Patient images were obtained by applying ADMIRE strength 2 and 3, and kernel B40 and B59. For quantitative evaluations, the noise level, spatial resolution, and overall image quality were measured using coefficient of variation (COV), edge rise distance (ERD), and natural image quality evaluation (NIQE). The superior values for the average COV, ERD, and NIQE results were obtained for the ADMIRE reconstruction conditions of ADMIRE 2 + B40, ADMIRE 3 + B59, and ADMIRE3 + B59. NIQE, which represents the overall image quality based on no-reference, was about 6.04 when using ADMIRE 3 + B59, showing the best result among the reconstructed image acquisition conditions. The results of this study indicate that the ADMIRE strength and kernel chosen for use in ADMIRE reconstruction have a significant impact on CT image quality. This highlights the importance of adjusting to the control factors in consideration of the clinical environment.

• Safety and Health at Work
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• v.14 no.4
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• pp.358-367
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• 2023

Background: This study aimed to develop and assess the psychometric features of the Physical Activity at Workplace Questionnaire (PAWPQ) based on the Social Cognitive Theory (SCT) to evaluate employees' physical activity (PA) behaviors at the workplace. Methods: This psychometric cross-sectional study was conducted on 455 employees working in one of the gas refineries in Iran. The participants were selected using the proportional stratified sampling method in 2019. The data collection tools were a demographic information questionnaire, the short form of the International Physical Activity Questionnaire (IPAQ), and a questionnaire developed based on the SCT, whose psychometric features were confirmed in terms of validity and reliability. Data were analyzed using SPSS₂₂ and AMOS₂₀ software. Results: The first version of PAWPQ-SCT had 74 items. After evaluating content and face validity, nine items were removed. The results of the content validity index (0.98), content validity ratio (0.86), and impact score (3.62) were acceptable for the whole instrument. In exploratory factor analysis, after removing seven items-58-item final version of the scale-six factors could explain 73.54% of the total variance. The results of structural equation modeling showed the acceptable fit of the model into the data (RMSEA = 0.052, CFI = 0.917, NFI = 0.878, TLI = 0.905, IFI = 0.917, CMIN/DF = 2.818). Cronbach's alpha coefficient and Intraclass Correlation were 0.90 and 0.86, respectively. Conclusion: This study confirmed that the psychometric features of the 58-item final version of PAWPQSCT constructs were acceptable in a sample of Iranian employees. This questionnaire can be used as a valid and reliable tool to evaluate Iranian employees' PA behaviors and develop effective educational interventions for workers and managers.

• Journal of Drive and Control
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• v.21 no.2
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• pp.36-43
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• 2024

The yield is basic and necessary information in precision agriculture that reduces input resources and enhances productivity. Yield information is important because it can be used to set up farming plans and evaluate farming results. Yield monitoring systems are commercialized in the United States and Japan but not in Korea. Therefore, such a system must be developed. This study was conducted to develop a yield monitoring system that improved performance by correcting a previously developed flow sensor using a grain tank-weighing system. An impact-plated type flow sensor was installed in a grain tank where grains are placed, and grain tank-weighing sensors were installed under the grain tank to estimate the weight of the grain inside the tank. The grain flow rate and grain weight prediction models showed high correlations, with coefficient of determinations (R2) of 0.9979 and 0.9991, respectively. A main controller of the yield monitoring system that calculated the real-time yield using a sensor output value was also developed and installed in a combine harvester. Field tests of the combine harvester yield monitoring system were conducted in a rice paddy field. The developed yield monitoring system showed high accuracy with an error of 0.13%. Therefore, the newly developed yield monitoring system can be used to predict grain weight with high accuracy.

• Korean Journal of Agricultural and Forest Meteorology
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• v.26 no.2
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• pp.115-125
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• 2024

Wind is a meteorological factor that has a significant impact on agriculture. Gust cause damage such as fruit drop and damage to facilities. In this study, low-altitude wind speed prediction was performed by applying physical models to Local Ensemble Prediction System (LENS). Logarithmic Law (LOG) and Power Law (POW) were used as the physical models, and Korea Ministry of Environment indicators and Moderate Resolution Imaging Spectroradiometer (MODIS) data were applied as indicator variables. We collected and verified wind and gust data at 3m altitude in 2022 operated by the Rural Development Administration, and presented the results in scatter plot, correlation coefficient, Root Mean Square Error (RMSE), Normalized Root Mean Square Error (NRMSE), and Threat Score (TS). The LOG-applied model showed better results in wind speed, and the POW-applied model showed better results in gust.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.19 no.4
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• pp.8-17
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• 2023

The air temperature is gradually increasing owing to global warming, especially in summer, therefore, the performance of an air source heat pump (ASHP) is expected to be decreased. Accordingly, the performance gap between the ASHP and ground source heat pump (GSHP) should be increased, however, the quantitative comparison has not been yet investigated. In this study, impact of global warming on the performance of the ASHP and GSHP is investigated based on the climate data for 1930, 1980, and 2030. The coefficient of performance (COP) as well as annual power consumption of the ASHP and GSHP are compared and analyzed. In the case of COP, the COP of GSHP hardly changes over the years owing to the constant ground temperature, while that of ASHP decreases by 3.7% for cooling and increases by 0.71% for heating. In the case of annual power consumption, the cooling and heating power consumption of GSHP increases by 12.69% and decreases by 15.58%, respectively, over the year owing to the changes in heating and cooling loads. As for the ASHP, the cooling and heating power consumption increases by 16.64% and decreases by 17.8%, respectively. For a more accurate comparison, power consumption ratio is introduced and shows that total annual power consumption of the GSHP to ASHP decreased from 68% in 1930 to 65% in 2030. Therefore, as global warming accelerates, the effect of reducing power consumption by using GSHP compared to ASHP is expected to be increasing.

• The Journal of Korean Academic Society of Nursing Education
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• v.30 no.3
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• pp.212-221
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• 2024

Purpose: This study aimed to identify the mediating effect of social phobia between social interaction anxiety and endemic blue among university students who experienced the coronavirus disease 2019 (COVID-19) pandemic. Methods: This study employed a descriptive correlational design. The participants were 196 university students from 10 universities located in four major regions across the Republic of Korea. Data were collected from July 12 to 31, 2022, through an online self-reported questionnaire and were then analyzed using an independent t-test, one-way ANOVA with Scheffé test, Pearson's correlation coefficient, and multiple regression. The mediating effect was analyzed using PROCESS macro model 4 with a bootstrapping method using IBM SPSS 27.0. Results: There were significant positive correlations among social interaction anxiety, social phobia, and endemic blue. Social interaction anxiety had significant effects on social phobia (β=0.77, p<.001) and social interaction anxiety (β=0.33, p<.001) and social phobia had a significant effect on endemic blue (β=0.29, p=.001). Concerning the influence of social interaction anxiety on endemic blue, a significant indirect mediating effect of social phobia was confirmed, and the size of the indirect effect was 0.14 (0.04~0.24). Conclusion: In order to manage the social and psychological health of university students who experienced the COVID-19 pandemic period, it is necessary to develop strategies to overcome endemic blue that reduce social interaction anxiety and take into account the mediating effect of social phobia.

• Journal of Korean Clinical Nursing Research
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• v.30 no.2
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• pp.75-83
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• 2024

Purpose: This study is descriptive research to examine the effects of the clinical nurse's character and nursing informatics competencies of nurses working at veterans hospitals on their nursing performance. Methods: Data were collected from 192 nurses with over one year of clinical experience working at three veterans' hospitals in B, D, and G Metropolitan from September 6 to September 30, 2021. The collected data were analyzed with the SPSS 25.0 program in descriptive statistics, an independent t-test, ANOVA, Pearson's correlation coefficient, and multiple regression. The Scheffé test was used as a post hoc test. Results: Nursing performance had a statistically significant positive correlation with the clinical nurse's character (r=.69, p<.001) and nursing informatics competency (r=.73, p<.001). The study results showed that nursing informatics competency (β=.49, p<.001) and the clinical nurse's character (β=.41, p<.001) significantly affected nursing performance. The total explanatory power of these variables was 62.4% (F=32.26, p<.001). Conclusion: The above results of this study show that the most significant factors in nursing performance are nursing information competency and the clinical nurse's character exhibit better nursing performance. Programs for improving nursing informatics competency and implementation methods need to be developed to improve nursing performance. It is also necessary to apply an effective clinical nurse's character program to enhance the level of the clinical nurse's character.

• Journal of radiological science and technology
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• v.47 no.5
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• pp.367-374
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• 2024

Education on start-ups and social support through various programs can greatly assist students who are either planning to start a business or have future entrepreneurial aspirations. This study aims to examine the impact of entrepreneurship education, social support, and awareness of the intend to start a business for students enrolled in radiological science program at local universities. The reliability of the questionnaire tool was confirmed with a Cronbach's Alpha coefficient of .06 or higher in the variable. The result of the independent sample t-test using the Boot Strap technique was classified by gender, revealed significant differences in the intention to start a business and innovation. The Bias-Corrected and Accelerated (BCa) 95% confidence interval for the intention to start a business and innovation was lower at .268 and .100, respectively, and the upper limit was .825 and .457, indicating a significant difference as the interval did not include zero. As a result of regression analysis, analysis demonstrated that among the sub-factors of entrepreneurship, innovation (p<.05) and risk sensitivity (p<.001) significantly influenced the willingness to start a business. These findings suggest that comprehensive education on start-ups, along with the provision of appropriate support mechanisms, is essential to ensure the students do not miss out on entrepreneurial opportunities due to a lack of related resources and support.