• Journal of Korean Physical Therapy Science
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• v.27 no.3
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• pp.45-55
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• 2020

Background: The purpose of this study was to investigate the effects of WBC (whole-body cryotherapy)on the MVIC (maximal voluntary isometric contraction)and active ROM (range of motion) recovery of after EIMD (exercise-induced muscle injury). Design: Randomized Controlled Trial. Methods: Thirty subjects who are student in their 20s at a university participated in this study, these subjects were assigned into three groups, a control group (n=10), experiment group I(n=10), and experiment group II (n=10). The subjects in the experimental group II were intervened by WBC (-130℃, 3 minutes) before induced EIMD, the experimental group were intervened by WBC (-130℃, 3 minutes) after induced EIMD, and the control group weren't by any intervened after induced EIMD. Results: First, In the comparison of the MVIC, there were significant variations with the lapse the time in three groups (p<.001) and there was a significant interaction of time and group (p<.001). In the among group comparison, the MVIC of experimental group II was significantly larger than those of other groups (p<.001). Second, In the comparison of the active extension angle, there were significant variations with the lapse the time in three groups (p<.001) and there was a significant interaction of time and group (p<.001). In the among group comparison, the active extension angle of experimental group II was significantly smaller than those of other groups (p<.001). Third, In the comparison of the active flexion angle, there were significant variations with the lapse the time in three groups (p<.01) and there was a significant interaction of time and group (p<.001). In the among group comparison, the active flexion angle of experimental group II was significantly larger than those of other groups (p<.05). Conclusion: The above results revealed that the WBC intervention after an exercise had a positive effect of muscle function after EIMD. Therefore we can consider the WBC as a considerable intervention method to prevent or reduce an exercise injury.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.6
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• pp.341-348
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• 2021

Serum amylase is a representative enzyme secreted by the salivary gland and pancreas. This study investigates the clinical significance of serum amylase levels in Sjögren's syndrome (SS). Totally, 70 female subjects were enrolled, who were diagnosed as SS and had no accompanying afflictions that affected the serum amylase levels. Unstimulated salivary flow rate (U-SFR) and stimulated SFR (S-SFR), salivary gland scan, and disease activity markers (ESSDAI and ESSPRI), as well as blood tests including ESR, CRP, and amylase, were evaluated. Serum amylase showed significant positive correlation with the U-SFR and S-SFR, and was increased with higher ejection fraction (EF) of the parotid gland. However, there was no significant correlation with disease activity and inflammatory markers. Based on their average amylase levels, subjects were divided into two groups. The group with higher serum amylase levels showed a statistically significant increase in the S-SFR and EF of the parotid gland. Considering the results of the salivary gland scan, we conclude that serum amylase is significantly correlated with SFR and the EF of the parotid gland, thereby indicating that the salivary gland function remains intact in SS.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.20 no.4
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• pp.41-52
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• 2010

Message authentication is an essential security element in vehicular ad-hoc network(VANET). For a secure message authentication, integrity, availability, privacy preserving skill, and also efficiency in various environment should be provided. RAISE scheme has been proposed to provide efficient message authentication in the environment crowded with lots of vehicles and generally considered to be hard to provide efficiency. However, as the number of vehicles communicating in the area increases, the overhead is also incurred in proportion to the number of vehicles so that it still needs to be reduced, and the scheme is vulnerable to some attacks. In this paper, to make up for the vulnerabilities in dense vehicular communication network, we propose a more secure and efficient scheme using a process that RSU(Road Side Unit) transmits the messages of neighbor vehicles at once with Bloom Filter, and timestamp to protect against replay attack. Moreover, by adding a handover function to the scheme, we simplify the authentication process as omitting the unnecessary key-exchange process when a vehicle moves to other area. And we confirm the safety and efficiency of the scheme by simulating the false positive probability and calculating the traffic.

• The Journal of the Korea Contents Association
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• v.20 no.12
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• pp.417-425
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• 2020

In the present study, practical measures were to be presented for prevention of smartphone game addiction and school violence by analysis of the effects aspect of the smartphone game addition by elementary school students on school violence awareness. For this purpose, a questionnaire survey was conducted for the subject of 6th graders attending an elementary school located in K city of Jeollanam-do, and a total of 258 copies were utilized as the final analysis data. Considering the analysis results, significant differences in the smartphone game addition were observed first as a function of the elementary school students' sex and game use time. The level of smartphone game addiction was observed to become higher for male students than female students, and the higher the longer the game use time during a day. Secondly, a positive (+) correlation was observed to exist between the smartphone game addiction and the school violence awareness. Thirdly, the variable affecting the school violence awareness among individual sub-variables for the smartphone game addiction was shown to be a problem with loss of control and power of reality test. The higher the addiction level of each variable, the negative tendency for school violence awareness was shown to be increased. Based on such analysis results, policy-wise, practical suggestions as well as directions for the follow-up studies have been presented for the improvement of smartphone game addiction and school violence awareness.

• The Journal of the Korea Contents Association
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• v.21 no.6
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• pp.653-662
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• 2021

This is a thesis about the whole process of cooperative study for the project, 'Jeju Tamranun idea' which produced by Capstone Design Class in communication design Dept, Hongik University. The purpose of this thesis is to know the primary educational goal and essence of capstone design class and to find the enhancement plan for the local design industry. The exhibitional project, 'Jeju Tamranun idea' was operated three times by hongik university with the company based on Jeju from 2017 to 2019. After the research, There are three positive effects of this project which are the new social function of the discarded assignments, the improvement of educational standard through the autonomous competition, and the growth of students' social consciousness in the process of considering local industries. And there are several points to be reviewed for a better capstone design class with local design industries. It is necessary to utilize the untact system for solving distance issues. And also, absolute evaluations, giving equal reward, and copyright protection are needed. Lastly, the continuous development of the curriculum to improve local design industries is needed.

• Korean Journal of Optics and Photonics
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• v.31 no.6
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• pp.281-289
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• 2020

This paper reports a slim mobile lens design using a hybrid refractive/diffractive optical element. Conventionally a wide field of view (FOV) camera-lens design adopts a retrofocus type having a negative (-) lens at the forefront, so that it improves in imaging performance over the wide FOV, but with the sacrifice of longer total track length (TTL). However, we chose a telephoto type as a baseline design layout having a positive (+) lens at the forefront, to achieving slimness, based on the specification analysis of 23 reported optical designs. Following preliminary optimization of a baseline design and aberration analysis based on Zernike-polynomial decomposition, we applied a hybrid refractive/diffractive element to effectively reduce the residual chromatic spherical aberration. The optimized optical design consists of 6 optical elements, including one hybrid element. It results in a very slim telephoto ratio of 1.7, having an f-number of 2.0, FOV of 90°, effective focal length of 2.23 mm, and TTL of 3.7 mm. Compared to a comparable conventional lens design with no hybrid elements, the hybrid design improved the value of the modulation transfer function (MTF) at a spatial frequency of 180 cycles/mm from 63% to 71-73% at zero field (0 F), and about 2-3% at 0.5, 0.7, and 0.9 fields. It was also found that a design with a hybrid lens with only two diffraction zones at the stop achieved the same performance improvement.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.15 no.6
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• pp.55-65
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• 2020

The purpose of this study is to empirically analyze the factors that affect start-up activities at the national level. Unlike most existing research about entrepreneurship at the individual level, this empirical analysis makes use of the total early-stage entrepreneurial activity(TEA) index at national level. This was developed by the Global Entrepreneur Monitor (GEM) as the measure for the degree of entrepreneurship of the countries. Based on the previous studies, not only national income level and unemployment rate, but also other factors including the cultural characteristics of the countries were included in our regression model. Using GEM's panel data, we found that the effectiveness of the factors depends on the stage of economic development. In particular, we found 'U-shape' relationship between the level of per capita income and entrepreneurship activity by the panel regression analysis using quadratic function. This analysis result can explicitly confirm what the existing literature have explained descriptively. Furthermore, the governmental support programs are shown to have significantly positive effects on the entrepreneurship or start-up activities in the factor-driven and efficiency-driven economies. On the contrary, those programs were not very helpful in the innovative economies. Lastly, this research suggests that the 'education and training' and the 'entrepreneurial culture' be the supportive norm for new business regardless of the economic development level.

• Journal of the Korea Convergence Society
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• v.13 no.4
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• pp.261-270
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• 2022

For mobile online games, this study examines how use pursuit propensity, use interest, use, service quality, and system quality, which are attributes that evaluate the use value and benefit for Chinese users, have an effect on use satisfaction. Empirical analysis results; all composing factors of four attribute had a positive effect, and the degree of effect was different according to game types in use interest and use, service quality. In terms of use pursuit, there was no difference between game types, and innovation pursuit and relationship pursuit were found to be similarly important effecting factors. In terms of use interest, there was a difference between game types. Sense of solidarity in single-player game and sense of achievement in multi-player game was found to be the most important effecting factor. In terms of service quality, there was a difference between game types. Easy of game in single-player game and function of game in multi-player game was the most important effecting factor. In terms of system quality, use convenience was found the most important effecting factor without difference between game types. Based on these results, this study suggested a strategy to enhance game development and loyalty to companies in the game industry.

• Journal of Gastric Cancer
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• v.22 no.2
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• pp.135-144
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• 2022

Purpose: This study aimed to compare the surgical and oncological outcomes between totally laparoscopic pylorus-preserving gastrectomy (TLPPG) with intracorporeal anastomosis and laparoscopy-assisted pylorus-preserving gastrectomy (LAPPG) with extracorporeal anastomosis. Materials and Methods: A retrospective analysis was performed in 258 patients with cT1N0 gastric cancer who underwent laparoscopic pylorus-preserving gastrectomy using two different anastomosis methods: TLPPG with intracorporeal anastomosis (n=88) and LAPPG with extracorporeal anastomosis (n=170). The following variables were compared between the two groups to assess the postoperative surgical and oncological outcomes: proximal and distal margins, number of resected lymph nodes (LNs) in total and in LN station 6, operation time, postoperative hospital stay, and postoperative morbidity including delayed gastric emptying (DGE). Results: The average length of the proximal margin was similar between the TLPPG and LAPPG groups (2.35 vs. 2.73 cm, P=0.070). Although the distal margin was significantly shorter in the TLPPG group than in the LAPPG group (3.15 vs. 4.08 cm, P=0.001), no proximal or distal resection margin-positive cases were reported in either group. The average number of resected LN was similar in both groups (36.0 vs. 33.98, P=0.229; LN station 6, 5.72 vs. 5.33, P=0.399). The operation time was shorter in the TLPPG group than in the LAPPG (200.17 vs. 220.80 minutes, P=0.001). No significant differences were observed between the two groups in terms of postoperative hospital stay (9.38 vs. 10.10 days, P=0.426) and surgical complication rate (19.3% vs. 22.9%), including DGE (8.0% vs. 11.8%, P=0.343). Conclusions: The oncological safety and postoperative complications of TLPPG with intracorporeal anastomosis are similar to those of LAPPG with extracorporeal anastomosis.

• Korean Journal of Culture and Social Issue
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• v.26 no.3
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• pp.221-257
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• 2020

This study examined whether popular music lyrics, the new research topic, reflect changes in Koreans' cultural orientation and whether individuals' cultural orientation is related to the genre of popular music that they prefer. In Study 1, we content analyzed popular music lyrics from 1980 to 2018 to see if Koreans' cultural orientations changed over time. The analysis showed that as the release dates approached the 2010s, the lyrics expressed the ideal attitudes of individualist cultures more frequently than those of collectivist cultures; this suggests that Koreans have gradually become more individualistic over time. In Study 2, we examined the relationships between individuals' cultural orientations, preferences for various genres of popular music, and functions of music. The analysis showed that people with more collectivistic attitudes tended to prefer mid- and low-arousal music, such as Ballads and Rap/Hiphop, while those with less collectivistic attitudes preferred high-arousal music, such as Rock/Metal. This result is partly consistent with the hypothesis that collectivistic people would prefer lower to higher arousal music. In addition, our analysis showed the strongest positive relationship between collectivism and the social function of music; this result can be interpreted as indicating that collectivistic people use music to maintain good interpersonal relationships. This paper concludes by discussing the implications of these findings, the limitations of this study, and directions for further research.