• Korean Journal of Applied Biomechanics
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• v.31 no.4
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• pp.308-313
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• 2021

Objective: The purpose of this study was to investigate the effect of different kettlebell mass (30%, 40%, and 50% of the body mass) on kinematics and kinetic variables of kettlebell swing. Method: Total of 16 healthy male who had at least 1 year of kettlebell training experience were participated in this study (age: 31.69 ± 3.46 yrd., height: 173.38 ± 4.84 cm, body mass: 74.53 ± 6.45 kg). In this study, a 13-segments whole-body model (upper trunk, lower trunk, pelvis, both side of forearm, upperarm, thigh, and shank) was used and 26 reflective markers were attached to the body to identify the segments during the movement. A 3-dimensional motion analysis with 8 infrared cameras and 4 channeled EMG was performed to find the effect of kettlebell mass on its swing. To verify the kettlebell mass effect, a one-way ANOVA with a repeated measure was used and the statistical significance level was set at 𝛼=.05. Results: Firstly, in all lower extremity joints and thoracic vertebrae, a statistically significant change in angle was shown according to an increase in kettlebell mass during kettlebell swing (p<.05). Secondly, in both the up-swing and down-swing phases, the knee joint and ankle joint ROM showed a statistically significant increase as the kettlebell mass increased (p<.05) but no statistically significant difference was found in the hip joint and thoracic spine (p>.05). Lastly, the hamstrings muscle activity was statistically significantly increased as the kettlebell mass increased during up-swing phases (p<.05). Also, as the kettlebell mass increased in P4 of the down swing phase, the gluteus maximus showed a statistically significantly increased muscle activation, whereas the rectus femoris showed a statistically significantly decreased muscle activation (p <.05). Conclusion: As a result of this study, hip extension decreased and knee extension increased at 40% and 50% of body mass, and the spine also failed to maintain neutrality and increased flexion. Also, when kettlebell swings are performed with 50% of body mass, synergistic muscle dominance appears over 30% and 40% of body mass, which is judged to have a risk of potential injury. Therefore, it is thought that for beginners who start kettlebell exercise, swing practice should be performed with 30% of body mass. In addition, even in the case of experienced seniors, as the weight increases, the potential injury risk may increase, so it is thought that caution should be exercised when performing swings with 40% and 50% of body mass. In conclusion, it is thought that increasing the weight after sufficiently training with 30% of the weight of all subjects performing kettlebell swing is a way to maximize the exercise effect as well as prevent injury.

• Journal of the Korea Convergence Society
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• v.12 no.9
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• pp.113-120
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• 2021

As a result, the interaction between personal motivation and class type is not significant. On the other hand, the interaction between social motivation and class type is significant and overall online class increases engagement with educational issues. In particular, the group with low social motivation showed greater change than the group with high social motivation, so online education seems to be more effective in the group with low social motivation. It means that by stimulating students' social motivation rather than personal motivation, the effectiveness of online education can be enhanced, and it can lead to education outcomes - behavioral changes and attitudes of learners. In order to revitalize social motivation in the intensely personal space of online, it is necessary to activate social communication methods such as SNS, and development of interpersonal issues and learning materials would be more efficient. In order to derive more specific results, it is necessary to measure the level of prior knowledge and involvement of the participants in class, and to comprehensively investigate and analyze the state of learners before and after class through more variables. Finally, in order to increase the reliability of the research results, it is necessary to clearly prove it through the establishment of a structural model.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.3
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• pp.318-323
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• 2019

In this study, we examined the differences in age among the various functions required for everyday life through smartphone using environment. The subjects were composed of 30 young adults and 30 elderly people. We set up 12 tasks to evaluate the performance of smartphone functions. At the same time, a questionnaire about smartphone usage habits was made. The questionnaire consists of items related to user history and usage habits. ANOVA analysis was performed using Minitab version 14, and statistically significant differences were found in 10 tasks. The result of the actual values for each task showed that the elderly generally took more time to perform all the tasks than the younger ones. Especially, the tendency of the task which requires a lot of keystrokes was revealed. Especially, in the case of a task requiring a lot of keystrokes, the tendency was remarkable. Young adults have found that they use all functions uniformly overall, and the functions used by the elderly were biased toward some functions, such as dialing, text, kakao talk, and searching. These results suggest that young people use smartphones more frequently than elderly people, and as they become accustomed to using smartphones, the time required to perform functions may be shortened. We suggest that it is necessary to design in terms of hardware or software so that the elderly people can input easily and conveniently.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.4
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• pp.129-136
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• 2019

This study was conducted to identify the health promotion behavior of patients with pulmonary tuberculosis and examine the factors influencing this behavior. The subjects were 152 outpatients who were treated for pulmonary tuberculosis at the national tuberculosis hospital located in M City. Data were collected from July to September, 2016 and analyzed using the t-test, ANOVA, Duncan's test, Pearson's correlation coefficient, and multiple regression analysis. Health promotion behavior was negatively correlated with physical symptoms, perceived barriers, and depression, but positively correlated with self-efficacy. The most powerful variable influencing health promotion behavior was depression and the model showed an explanatory power of 63.5%. The results of this study suggest that it is necessary to employ a variety of strategies to practice and maintain the health promotion behavior of pulmonary tuberculosis patients to decrease their depression and provide psychological support.

• Journal of Korean Medicine Rehabilitation
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• v.29 no.3
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• pp.87-101
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• 2019

Objectives The purpose of this study is to investigate characteristics of low back pain patients and trends of Korean medicine conservative treatment effects of low back pain patients by registry data. Methods A total of 78 patients were analyzed, statistical analysis was performed using a generalized linear model. The comparison between groups was performed using independent two samples t-test or Wilcoxon rank sum test according to the distribution of normality. Before and after the treatment effects, ANOVA and Kruskal-Wallis method were used for the comparison, Sheffe method was used for the post test. Results The average age of hospitalized patients was 31.8 years old and out-patient department (OPD) patients was 44.9 years old. Lots of OPD patients and hospitalized patients were classified to 'Lumbago due to Coexist Qu Stagnation and Bloos Stasis'. Both OPD patients and hospitalized patients classified to 'Lumbago due to Coexist Qu Stagnation and Bloos Stasis' showed statistically significant decrease in RMDQ (Roland-Morris disability questionnaire) and NRS (numeric rating scale) on 1 month and 3 month after clinical research start date. Comparing the treatment effects of Chuna manual therapy, both Chuna group and non-Chuna group showed statistically significant decrease in RMDQ and NRS on discharge date, 1 month and 3 month after clinical research start date. Conclusions We expect that a larger scale registry study will be carried out to provide a higher level of basis for the Korean medical treatment of low back pain.

• Korean Journal of Applied Biomechanics
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• v.32 no.1
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• pp.17-23
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• 2022

Objective: The aim of this study was to investigate the effect Tiger-step walking on the movement of the lower extremities during walking. Method: Twenty healthy male adults who had no experience of musculoskeletal injuries on lower extremities in the last six months (age: 26.85 ± 3.28 yrs, height: 174.6 ± 3.72 cm, weight: 73.65 ± 7.48 kg) participated in this study. In this study, 7-segments whole-body model (pelvis, both side of thigh, shank and foot) was used and 29 reflective markers and cluster were attached to the body to identify the segments during the gait. A 3-dimensional motion analysis with 8 infrared cameras and 7 channeled EMG was performed to find the effect of tigerstep on uphill walking. To verify the tigerstep effect, a one-way ANOVA with a repeated measure was used and the statistical significance level was set at α=.05. Results: Firstly, Both Tiger-steps showed a significant increase in stance time and stride length compared with normal walking (p<.05), while both Tiger-steps shown significantly reduced cadence compared to normal walking (p<.05). Secondly, both Tiger-steps revealed significantly increased in hip and ankle joint range of motion compared with normal walking at all planes (p<.05). On the other hand, both Tiger-steps showed significantly increased knee joint range of motion compared with normal walking at the frontal and transverse planes (p<.05). Lastly, Gluteus maximus, biceps femoris, medial gastrocnemius, tibialis anterior of both tiger-step revealed significantly increased muscle activation compared with normal walking in gait cycle and stance phase (p<.05). On the other hand, in swing phase, the muscle activity of the vastus medialis, biceps femoris, tibialis anterior of both tiger-step significantly increased compared with those of normal walking (p <.05). Conclusion: As a result of this study, Tiger step revealed increased in 3d range of motion of lower extremity joints as well as the muscle activities associated with range of motion. These findings were evaluated as an increase in stride length, which is essential for efficient walking. Therefore, the finding of this study prove the effectiveness of the tiger step when walking uphill, and it is thought that it will help develop a more efficient tiger step in the future, which has not been scientifically proven.

• Journal of Korea Port Economic Association
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• v.37 no.2
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• pp.133-152
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• 2021

The purpose of this study is to investigate the factors affecting the wages of workers in the logistics industry and to identify the current status of employment and wages in the logistics industry. Based on this, it sought to find analytical factors on the wages of workers in the logistics industry and explain their impact on the wage gap. The analysis data were interpreted as cross-sectional data from the National Statistical Office over the past decade and the analysis data were set to three types. The results of the analysis could be explained that three factors understood as wage discrimination factors that do not directly affect productivity generally have a significant impact on wage gap among workers in the logistics industry. Air and water transport industries received high salaries due to factors in the industry. The very low-paid sector for that was the land transport industry, and the courier industry as a detailed sector. Due to the nature of job factors, technicians and assistants received lower wages than other jobs. Due to the nature of the company's size factors, companies with 51 or more employees received higher wages than companies with 50 or less employees. In testing the effectiveness of multiple sources of ANOVA, the common 'industry × enterprise size' variable was explained to have a significant effect on gaps in wages for workers in the logistics industry. In addition, the comparison of the influence of the main effects of the three factors put into the analysis model shows that the industry has the most influence.

• Korean Association of Arts Management
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• no.58
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• pp.89-119
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• 2021

This study empirically analyzes the factors that affect the people's enjoyment of pure culture and arts, especially art exhibitions. We use 56,588 sample data from the "The Survey of Cultural Enjoyment" collected by the Ministry of Cultrure, Sports and Tourism over the last 10 years and perform multiple regression and Multi-Way ANOVA to analyze the effect of individual's cultural experience on art exhibit visits. The results of the analysis show that the experience of participating in culture and arts events, culture and arts education, and participation in culture and arts clubs have a positive effect on the art exhibition visits. We also identify the positive interaction effects between the three independent variables. In other words, it was found that the average number of visits to art exhibitions was higher for groups who had experience of participating in culture and arts events, culture and arts education, and culture and arts clubs. This study provides a first empirical analysis on personal factors influencing art exhibition visits in Korea and lays the groundwork for future studies in developing a comprehensive predictive model for cultural art visits. In addition, we give policy implications and suggestions specifically, mid-term policies related to promoting art exhibition visits as an extension of individual's engagement with pure culture and arts through big data analysis.

• Journal of Korea Entertainment Industry Association
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• v.14 no.6
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• pp.61-76
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• 2020

As the media environment changes rapidly, the size of the online advertising market is growing rapidly. However, consumer's trustfulness in online advertising is much lower than that of old media, and there is also a phenomenon of advertising avoidance. Thus, in this study, advertising skepticism, advertising appeals, involvement, and FCB Grid theory were used to provide Youtube and advertisers with implications for advertising strategies. It was intended to provide a way to lower consumer advertising avoidance. As a result of Research 1, consumers with high advertising avoidance showed low advertising attitudes, brand attitudes, and attitudes toward products. In addition, there was no difference in gender, and when the frequency of online video viewing decreased and the age increased, advertising avoidance increased. Research 2 shows that consumers with high levels of advertising skepticism showed a high level of advertising attitude when the level of involvement was low and transformational appeal was high. In the FCB Grid model, consumers with high levels of advertising skepticism are found to be suitable for transformational appeal advertising. These results mean that Youtube and advertisers should think important about advertising skepticism, which is the cause of advertising avoidance, and that consumers with high levels of advertising skepticism should be presented with advertisements suitable for each type of product in the online advertising market.

• Journal of the Korea Convergence Society
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• v.12 no.11
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• pp.185-191
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• 2021

The purpose of this study is to develop middle school English classes using Problem-Based Learning(PBL) based on flipped learning and to examine its effects. Recently, various attempts to combine flipped learning and PBL have been made; however, many studies have not been applied to middle and high school curriculums yet. The attempt of this study is expected to have theoretical and practical significance. The instructional model was derived from the review of previous studies, and the development of instructional program followed the general design procedure(analysis-design-development-implement-evaluation), and its validity was secured with the advice of related experts. To verify the effectiveness of the program, the English academic achievement test and the English key competency test were conducted before and after the program. Changes in English academic achievement were analyzed by the paired-sample t-test, and the effect of key competency and the level of achievement test performance (high vs, low) on the pre-post score change was analyzed by the mixed effects repeated measures ANOVA. As a result of the analysis, both academic achievement and key competencies increased, and the low-level students in the pre-academic achievement test showed more improvements. In conclusion, the PBL class based on flipped learning is effective in improving the English academic achievement and key competencies of middle school students, and in particular, it is shown to be an effective teaching method for students with low academic achievement.