• Journal of the Korean Applied Science and Technology
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• v.39 no.6
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• pp.906-915
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• 2022

The purpose of this study was to investigate the effects of aquatic walking exercise on body composition, hs-CRP, HOMA-IR, and blood pressure in obese elderly women. Twenty, obese elderly women[percent body fat(%BF) < 30%] composed of aquatic walking exercise group(EX, n=10), the control group(CON, n=10). The variables of body composition, hs-CRP, HOMA-IR, and blood pressure were measured in all the subjects pre and post of 12 weeks aquatic walking exercise(RPE 11-14, 3 times per week, 50 mins). The test data were analyzed by paired t-test and repeated ANOVA, and the alpha level of p<.05 was set for all tests of significance. %BF (p<.05), insulin (p<.01), HOMA-IR (p<.01) and SBP (p<.05) were significantly decreased in EX group compared to CON group. These results suggest that 12 weeks of aquatic walking exercise improves %BF, HOMA-IR, and blood pressure. Thus, this proposed aquatic walking exercise modality can be a useful therapy to improve both obese and cardiovascular disease in obese elderly women.

• Journal of Venture Innovation
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• v.6 no.4
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• pp.113-131
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• 2023

Post-merger integration(PMI) plays a very important role in the success of M&A. Therefore, based on previous studies on PMI, this study discusses the relationship between communication of acquired enterprise members and uncertainty reduction, organizational satisfaction, organizational trust in the PMI process, focusing on the moderating effect of business area consistency between the acquisition and the acquired company. In order to achieve the purpose of this study, the hypothesis of the relationship between variables was established and an empirical analysis was conducted. In order to collect data, a survey was conducted on members of the acquired company in China, and 317 questionnaires were finally collected and used for empirical analysis. For the collected data, the research hypothesis was verified using SPSS 26.0. The results of the study confirmed that communication has a positive effect on the reduction of uncertainty, job satisfaction, and organizational trust perceived by members of the acquired company, and that the consistency in business areas between the acquisition and the acquired company weakens the relationship between communication and uncertainty. In the positive relationship between communication and job satisfaction, organizational trust, the effect of strengthening the moderating variable has not been confirmed, but rather the weakening control effect was found. Based on these findings, the strategy of communicating with the members of the acquired company in the PMI process is meaningful for the success or failure of the merger and provides theoretical and practical implications for proposing differentiated human resources management measures according to M&A type.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.17 no.5
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• pp.95-104
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• 2022

This study aims to find out the influence of the intolerance of uncertainty on entrepreneurial intention by focusing on the start-up support system awareness. While most of existing studies focused on the positive psychological variables and individual environmental characteristics influencing on the entrepreneurial intention, this study has taken a look at the influence of the intolerance of uncertainty as the psychological variable to the entrepreneurial intention to negatively act on the entrepreneurial intention. As a result of the analysis, the intolerance of uncertainty under the control of entrepreneurship and gender is shown to have the negative (-) influence on the entrepreneurial intention and has high level of recognition on the start-up support system perception, and the start-up support system perception is confirmed to have positive (+) influence on the entrepreneurial intention. And, it also indicates that, with respect to the influence of the intolerance of uncertainty on the entrepreneurial intention, the start-up support system perception has the partial medium effect. Following this result of the study, it provides following indications: First the existing studies on the entrepreneurial intention had not covered the intolerance of uncertainty but it is confirmed as the psychological variable with negative influence on the entrepreneurial intention. Second, it is feasible for the preliminary start-up businesses may turn the fear on start-up failure into positive entrepreneurial intention with the start-up support system perception as the leading vehicle. And, third, based on the result, the government should enhance the start-up support system perception even more by seeking ways of efficient publicity to enable more preliminary start-up businesses to participate in diverse start-up support policies. Lastly, it discusses the limitations of this study as well as proposal for ensuing study plans.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.17 no.4
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• pp.163-172
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• 2022

This study investigates the IPI (Information Protection Intention) of DHS (Digital Healthcare Service) providers by introducing PMT (Protection Motivation Theory). This study examines the effects of protection motivation, such as threat appraisal and coping appraisal, on IPI, such as ICI(Induction Control Intention) and SDI(Self Defense Intention). The research model, based on the PMT, adopted severity, vulnerability, reaction efficacy and self-efficacy as independent variables. The research model was validated through quantitative research, a survey of 222 DHS providers in South Korea, using structural equation modeling. The results show that (1) a clear awareness of the consequences of security threats increases the understanding of DHS providers on the severity of closure of healthcare information, and thus may decreases abuse of DHS by providers; (2) user confidence and satisfaction on the security system may make them be confident that they can handle the closure of healthcare information by themselves; and (3) although DHS providers are realizing the consequences of closure of healthcare information, they think that they are unlikely to encounter such situations. As a result of this study, venture companies that provide DHS need to provide contents that can continuously increase providers' security level in order to increase providers' information protection intention. It suggests that IPI is important through trust of healthcare service providers.

• Journal of Family Resource Management and Policy Review
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• v.27 no.4
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• pp.19-33
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• 2023

The purpose of this study was to examine the mediating effect of ego resilience on the relationship between family strengths of Chinese international students and Social Networking Services(SNS) addiction tendency. The data were collected through a survey of 349 Chinese international students studying in Korea and analyzed using the SPSS Statistics version 28 program and SPSS Process Macro 4.3. The main results are as follows. First, Chinese international students exhibited higher-than-average levels of SNS addiction tendency, family strengths, and ego resilience. Second, the SNS addiction tendency of Chinese international students had a significant positive correlation with the average time spend on SNS per day. while demonstrating a negative correlation with family strengths and ego resilience. Third, the hierarchical regression analysis revelated that gender, frequency of contact with family, average time spend on SNS per day, qualitative bond as a sub variable of family strengths, and control as a sub variables of ego resilience were significant factors influencing SNS addiction tendency of Chinese international students. Fourth, the study confirmed the complete mediation of ego resilience in the effect of family strengths on SNS addiction tendency. Based on the research results, this study suggested specific directions for counseling interventions aimed at mitigating SNS addiction tendencies among Chinese international students.

• Journal of the Korea institute for structural maintenance and inspection
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• v.28 no.1
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• pp.70-81
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• 2024

In this study, Tridimensional Hybrid Isolation System(THIS) was proposed as a vibration isolator for traffic loads, combining vertical and horizontal isolation systems. Its efficacy in improving serviceability for vertical vibration was analytically evaluated. Firstly, for the analysis, the major vibration modes of the existing apartment were identified through eigenvalue analysis for the system and pulse response analysis for the bedroom slab using commercial structural analysis software. Subsequently, a 16-story model with horizontal, vertical and rotational degrees of freedom for each slab was numerically organized to represent the achieved modes. The dynamic analysis for the measured acceleration from an adjacent ground to high-speed railway was performed by state-space equations with the stiffness and damping ratio of THIS as variables. The result indicated that as the vertical period ratio increased, the threshold period ratio where the slab response started to be suppressed varied. Specifically, when the period ratio is greater than or equal to 5, the acceleration levels of all slabs decreased to approximately 70% or less compared to the non-isolated condition. On the other hand, it was ascertained that the influence of damping ratios on the response control of THIS is inconsequential in the analysis. Finally, the improvement in vertical vibration performance of THIS was evaluated according to design guidelines for floor vibration of AIJ, SCI and AISC. It was confirmed that, after the application of THIS, the residential performance criteria were met, whereas the non-isolated structure failed to satisfy them.

• Composites Research
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• v.37 no.3
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• pp.219-225
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• 2024

It is essential to develop a light-weight, high-performance structure for the deployable reflector antenna, which is the payload of a reconnaissance satellite, considering launch and orbital operation performance. Among them, the composite main reflector is a key component that constitutes a deployable reflector antenna. In particular, the development of a high-performance main reflector is required to acquire high-quality satellite images after agile attitude control maneuvers during satellite missions. To develop main reflector, the initial design of the main reflector was confirmed considering the structural performance according to the laminate stacking design and material properties of the composite main reflector that constitutes the deployable reflector antenna. Based on the initial design, four types of composite main reflectors were manufactured with the variable for manufacturing process. As variables for manufacturing process, the curing process of the composite structure, the application of adhesive film between the carbon fiber composite sheet and the honeycomb core, and the venting path inside the sandwich composite were selected. After manufacture main reflector, weight measurement, non-destructive testing(NDT), surface error measurement, and modal test were performed on the four types of main reflectors produced. By selecting a manufacturing process that does not apply adhesive film and includes venting path, for a composite main reflector with light weight and structural performance, we developed and verified a main reflector that can be applied to the SAR(Synthetic Aperture Rader) satellite.

• Korea Journal of Hospital Management
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• v.29 no.1
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• pp.46-55
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• 2024

Objective: This study was conducted to provide basic data for the establishment of effective health policies for the unmet medical experience that may occur among the elderly depending on whether they live in a singleperson household or not. Methodology: This study used data from the 8th National Health and Nutrition Examination Survey (2019-2020) and excluded cases with missing values in variables for the total number of respondent participants of 15,469. Finally, 2,850 subjects aged 65 or older were selected for final analysis. This study examined the relationship between experiences of unmet medical needs, attempting to confirm the relationship between single-person households and unmet medical needs through subgroup analysis considering gender, age, and household income. Results: According to the results, in the case of single-person households, the odds ratio (OR) for unmet medical needs was significantly higher at 1.60 times (95% CI: 1.16-2.21). Upon conducting subgroup analyses for gender, age, and household income quintiles, the OR was significantly higher at 2.24 times (95% CI: 1.14-4.41) for males and 1.48 times (95% CI: 1.02-2.14) for females, statistically significant in both cases. For individuals aged 65-69, the OR was significantly higher at 1.90 times (95% CI: 1.04-3.47), but for those aged 70-74 and over 75, it was not statistically significant. In the case of households with 'low' income, the OR was higher at 1.62 times (95% CI: 1.16-2.26), and for 'middle' income, it was significantly higher at 3.21 times (95% CI: 1.08-9.51). Conclusion: This study confirmed that the experience of unmet medical care is high among men who make up single-person households and low-income seniors. Therefore, this study suggests that policies to expand medical services and support welfare for single-person households should be established to resolve these problems, showing that health policies that take into account individual and regional characteristics are needed to improve medical accessibility for single-person households.

• The Journal of the Acoustical Society of Korea
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• v.43 no.1
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• pp.103-111
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• 2024

Axial-flow fans are used to transport fluids in relatively low-pressure flow regimes, and a variety of design variables are employed. The tip geometry of an axial fan plays a dominant role in its flow and noise performance, and two of the most prominent flow phenomena are the tip vortex and the tip leakage vortex that occur at the tip of the blade. Various studies have been conducted to control these three-dimensional flow structures, and winglet geometries have been developed in the aircraft field to suppress wingtip vortices and increase efficiency. In this study, a numerical and experimental study was conducted to analyze the effect of winglet geometry applied to an axial fan blade for an air conditioner outdoor unit. The unsteady Reynolds-Averaged Navier-Stokes (RANS) equation and the FfocwsWilliams and Hawkings (FW-H) equation were numerically solved based on computational fluid dynamics techniques to analyze the three-dimensional flow structure and flow noise numerically, and the validity of the numerical method was verified by comparison with experimental results. The differences in the formation of tip vortex and tip leakage vortex depending on the winglet geometry were compared through a three-dimensional flow field, and the resulting aerodynamic performance was quantitatively compared. In addition, the effect of winglet geometry on flow noise was evaluated by numerically simulating noise based on the predicted flow field. A prototype of the target fan model was built, and flow and noise experiments were conducted to evaluate the actual performance quantitatively.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.44 no.3
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• pp.349-360
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• 2024

The purpose of this study is to analyze the performance of the road network according to the penetration rate of autonomous vehicles (AV) of Level 4 or higher and the change in traffic volume. First, prior studies related to vehicle control variables of AV were reviewed, and future traffic demand in 2040, which is predicted to have a 50 % market share of AVs, was reflected in the simulation analysis. In addition, the change in traffic flow of continuous and intermittent flows was analyzed by increasing the AV market penetration rate and traffic volume of passenger cars, trucks, and buses by 25 % step by step from 0 to 100 %. As a result of the analysis, it was confirmed that the travel time increased as the traffic increased, and the pattern of decreasing the travel time due to the increase in the share of AVs, that is, the development of technology, can also be confirmed. Furthermore, it was also confirmed that the traffic speed showed a trend of increasing as the share of AVs increased. In this study, it was confirmed that the law of diminishing marginal rate of substitution (MRS) was satisfied by calculating the MRS according to the combination of traffic volume and speed while increasing the market penetration rate of AVs. Furthermore, it was confirmed that the convexity of the indifference curve was also satisfied in both intermittent and continuous traffic flow environments.