• 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 the Korea Society of Computer and Information
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• v.28 no.11
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• pp.29-42
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• 2023

In this paper, we propose a method to enhance the prediction accuracy of solar irradiance for three major South Korean cities: Seoul, Busan, and Incheon. Our method entails the development of five generative models-vanilla GAN, CTGAN, Copula GAN, WGANGP, and TVAE-to generate independent variables that mimic the patterns of existing training data. To mitigate the bias in model training, we derive values for the dependent variables using random forests and deep neural networks, enriching the training datasets. These datasets are integrated with existing data to form comprehensive solar irradiance prediction models. The experimentation revealed that the augmented datasets led to significantly improved model performance compared to those trained solely on the original data. Specifically, CTGAN showed outstanding results due to its sophisticated mechanism for handling the intricacies of multivariate data relationships, ensuring that the generated data are diverse and closely aligned with the real-world variability of solar irradiance. The proposed method is expected to address the issue of data scarcity by augmenting the training data with high-quality synthetic data, thereby contributing to the operation of solar power systems for sustainable development.

• Journal of the Society of Disaster Information
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• v.19 no.4
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• pp.770-778
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• 2023

Purpose: In order to reduce forklift industrial accidents, it is necessary to classify them into institutional, technical, and educational factors and conduct research on whether each factor affects disaster reduction. Method: Descriptive statistical analysis, validity analysis, reliability analysis, and multiple regression analysis were conducted using SPSS 18 program based on an offline questionnaire based on a 5-point Likert scale. Result: As a result of multiple regression analysis, it was found that institutional, technical, and educational factors, which are independent variables for disaster reduction, explain about 62.5% of the variance in disaster prevention, which is the dependent variable. The regression model verification was found to be statistically significant with F=118.775 and significance probability p<0.01. Conclusion: First, there is a need to prevent disasters by including electric forklifts weighing less than 3 tons in the inspection system. Second, there is a need to make it mandatory to install front and rear cameras and forklift line beams to prevent forklift collision disasters. Third, there is a need to conduct special training related to forklifts every year, and drivers and nearby workers need to be included in the special training for forklifts.

• Korean Journal of Remote Sensing
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• v.39 no.6_3
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• pp.1721-1730
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• 2023

As awareness of the problem of global warming emerges around the world, the role of carbon sinks in settlement is increasingly emphasized to achieve carbon neutrality in urban areas. In order to manage carbon sinks in settlement, it is necessary to identify the current status of carbon sinks. Identifying the status of carbon sinks requires a lot of manpower and time and a corresponding budget. Therefore, in this study, a map predicting the location of trees was created using already established tree location information and Sentinel-2 satellite images targeting Seoul. To this end, after constructing a tree presence/absence dataset, structured data was generated using 16 types of vegetation indices information constructed from satellite images. After learning this by applying the Extreme Gradient Boosting (XGBoost) model, a tree prediction map was created. Afterward, the correlation between independent and dependent variables was investigated in model learning using the Shapely value of Shapley Additive exPlanations(SHAP). A comparative analysis was performed between maps produced for local parts of Seoul and sub-categorized land cover maps. In the case of the tree prediction model produced in this study, it was confirmed that even hard-to-detect street trees around the main street were predicted as trees.

• Journal of Venture Innovation
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• v.5 no.2
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• pp.1-14
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• 2022

Mobile shopping goes beyond the level of a tool that simply supports consumers' shopping in-store and creates a new level of experience for consumers through offline connection. It is important to acquire new customers in order to gain a competitive advantage through mobile shopping, but it is more important to maintain a continuous transaction relationship with the secured customers. Existing mobile shopping-related studies can be largely classified into three categories such as a study on the characteristics of mobile consumers, a study on the characteristics of a mobile shopping mall, and a study on the characteristics of mobile shopping itself. Therefore, this study aimed to analyze the impact of perceived value, perceived risk, and innovativeness on trust in mobile shopping. In order to investigate the impact of perceived value, perceived risk, consumer innovativeness on the trust in mobile shopping, consumers who have experience in purchasing products through mobile were investigated. The data collected in this study were verified the reliability and validity of the measurement items based on the measurement validation process. In this study, regression analysis was performed by selecting perceived value, perceived risk, innovativeness as independent variables, and trust as dependent variables. As a result of the analysis, perceived value, innovativeness had a positive impact on trust and perceived risk had a negative impact on trust. As a result of analysis, three hypotheses were supported. Finally, implications of the research are presented, and limitations and directions for future research are described.

• Journal of Venture Innovation
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• v.5 no.4
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• pp.23-39
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• 2022

This study was conducted to empirically analyze the factors influencing the intention to continue using live commerce, which was active as digital contacts become more prevailed due to the progress of the 4th industrial revolution and the COVID-19 pandemic. A research model was established by paying attention to the characteristics of influencers among various influencing factors. Influencer characteristics were subdivided into attractiveness, professionality, awareness, and entertainment. In addition, the dual mediating effect of interaction and trust was also tested between influencer's characteristics and the intention to continue using of live commerce. To this end, a survey was conducted targeting people who have experience using live commerce, and 300 valid samples were analyzed. The empirical analysis utilized SPSS 25.0 and Process Macro 4.0. As a result of the empirical analysis, it was found that attractiveness, professionality, awareness, and entertainment derived from the characteristics of influencers all had a significant positive (+) effect on the intention to continue using live commerce. The impact of the influence of variables that directly affect the intention to continue using was in the order of entertainment, awareness, professionality, and attractiveness. On the other hand, as a result of examining the dual mediating effect of interaction and trust, it was found that they all tested a mediating role between attractiveness, professionality, awareness, entertainment, and intention to continue using live commerce. Based on these research results, the academic and practical implications of this study were presented.

• Journal of Venture Innovation
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• v.6 no.3
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• pp.73-93
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• 2023

This study provides a prospect for the fast growing the smartwatch market by investigating the relationship between the satisfaction and the continuous use intention of Apple watch users, as well as the factors influencing their satisfaction. Based on the TAM, this study uses system quality, information quality, and self-efficacy as independent variables, perceived usefulness, perceived ease of use, and satisfaction as mediators, and continuous use intention as the dependent variable. We analyze the data of 256 individuals who completed an online survey with SPSS 26.0 and AMOS 26.0 software. This study conducts several tests and analyses to empirically evaluate the data including reliability analysis, factor analysis, feasibility analysis, path analysis, hypothesis verification, and mediation analysis. Our results investigate which factors may influence consumers' intention to continuously using Apple Watch devices in the future. In summary, satisfaction has a positive effect on the intention to continuously use smartwatchs. Perceived usefulness and perceived ease of use have a positive effect on satisfaction. Among the three factors (system quality, information quality, and self-efficacy), only self-efficacy has no significant impact on perceived usefulness but had a positive effect on perceived ease of use. In addition, system quality and information quality positively affect perceived usefulness, perceived ease of use, satisfaction, and continuous intention to use an Apple Watch. Taking the Apple Watch as the subject of our research topic, this study provides theoretical value by exploring the impact of user's satisfaction with their smartwatch on their continuous usage intention. This study further explains the influence of system quality, information quality, and self-efficacy on user satisfaction. Additionally, this research offers valuable insight to practitioners by confirming that information quality, system quality, and self-efficacy are important features for enhancing satisfactory user experiences which in turn may increase users' intention to continued using smartwatches.

• Journal of Venture Innovation
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• v.6 no.2
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• pp.101-121
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• 2023

The purpose of this study was to investigate the impact of issue leadership by sales managers on sales team performance, while examining the mediating role of team adaptive sales behavior and the moderating effect of team-member exchange (TMX). Data was collected from 125 sales teams, and both independent and dependent variables were measured with a time difference of two months using responses from sales managers and team members. The empirical analysis revealed several important findings. Firstly, the study found that issue leadership had a significant positive effect on sales team performance. Secondly, team adaptive sales behavior was found to partially mediate the relationship between issue leadership and sales team performance. Lastly, the study revealed that TMX moderated the relationship between issue leadership and sales team performance. These findings have significant academic and practical implications. Firstly, the study demonstrates the effectiveness of issue leadership as a sales leadership style in the B2C industry. Secondly, it highlights the importance of team adaptive sales behavior as a mechanism that mediates the relationship between issue leadership and sales team performance. Lastly, it underscores the significance of TMX as a situational factor that moderates the relationship between issue leadership and sales team performance. In practice, the results suggest that organizations should focus on developing issue leaders, fostering creative sales behavior at the team level, and activating social exchange within sales teams to enhance sales team performance.

• Journal of Venture Innovation
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• v.6 no.1
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• pp.161-179
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• 2023

More than 2 million foreigners were staying in Korea. In this study, the effect of individual and environmental characteristics of foreign workers on organizational commitment was empirically analyzed. A research model for empirical analysis was established. A research model was established independent variables by dividing them into four parts: personal desire, adaptability, organizational life, and social support and setting organizational commitment as dependent variables. Based on this research model, data collection for analysis was conducted in a survey method for foreign workers in Korea. An empirical analysis was conducted using SPSS 24 based on 200 valid sample of the respondents. The results of the empirical analysis were as follows. First, it was found that foreign workers' desire for achievement, language adaptability, relationships with supervisors and colleagues, future vision of jobs, and social support had a significant positive (+) effect on organizational commitment. On the other hand, the significant influence relationship of cultural adaptability was not tested. Second, factors that significantly affect organizational commitment was in the order of social support, relationships with supervisors and colleagues, future vision of jobs, language adaptability, and desire for achievement. Based on these research results, academic implications were presented, and practical implications were presented to increase the organizational commitment of foreign workers.

• Journal of Aerospace System Engineering
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• v.17 no.6
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• pp.1-8
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• 2023

Research, such as developing alternative energy in the transportation field, including aviation, is being actively conducted to solve the issue of current climate change. Interest in ammonia fuel as a carbon free energy (CFE) source is increasing due to the ease of liquefaction and transportation and similarity in energy density to that of methanol. However, explosiveness and toxicity of ammonia make it difficult to handle. Therefore, in this study, stable ammonia production was attempted using relatively easy-to-handle urea water solution (UWS). High temperature steam was used to promote the hydrolysis of ammonia. In order to determine the causes for ammonia production below the theoretical equivalent ratio, it was suggested that there were not enough collisions to promote the hydrolysis based on the kinetic theory of gases. The hydrolysis of unreacted isocyanic acid (HNCO) was tested according to the change in water supply. As a result, an increased amount of ammonia produced was confirmed. The increased amount of ammonia produced in a certain section was dependent on the steam temperature and the flow rate of water supplied.