• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.05a
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• pp.845-848
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• 2009

Power semiconductor devices are semiconductor devices used as switches or rectifiers in power electronics circuits. Theyare also caleed power devices or when used in integrated circuits, called power ICs. Some common power devices are the power diode, thyristor, power MOSFET and IGBT (insulated gate bipolar transistor). A power diode or MOSFET operates on similar principles to its low-power counterpart, but is able to carry a larger amount of current and typically is able to support a larger reverse-bias voltage in the off-state. Structural changes are often made in power devices to accommodate the higher current density, higher power dissipation and/or higher reverse breakdown voltage. The vast majority of the discrete (i.e non integrated) power devices are built using a vertical structure, whereas small-signal devices employ a lateral structure. With the vertical structure, the current rating of the device is proportional to its area, and the voltage blocking capability is achieved in the height of the die. With this structure, one of the connections of the device is located on the bottom of the semiconductor.

• Journal of the Korea Society of Computer and Information
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• v.25 no.4
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• pp.19-27
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• 2020

In this paper, we propose a machine learning method for diagnosing the failure of a gas pressure regulator. Originally, when implementing a machine learning model for detecting abnormal operation of a facility, it is common to install sensors to collect data. However, failure of a gas pressure regulator can lead to fatal safety problems, so that installing an additional sensor on a gas pressure regulator is not simple. In this paper, we propose various machine learning approach for diagnosing the abnormal operation of a gas pressure regulator with only the flow rate and gas pressure data collected from a gas pressure regulator itself. Since the fault data of a gas pressure regulator is not enough, the model is trained in all classes by applying the over-sampling method. The classification model was implemented using Gradient boosting, 1D Convolutional Neural Networks, and LSTM algorithm, and gradient boosting model showed the best performance among classification models with 99.975% accuracy.

• International Area Studies Review
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• v.17 no.4
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• pp.1-21
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• 2013

This study aims at conducting a quantitative assessment of potential economic effects of the Regional Comprehensive Economic Partnership (RCEP) consisting of 10 Member States of the ASEAN, Australia, China, India, Japan, Korea and New Zealand using a multi-region, multi-sector CGE model. Three different policy scenarios are carried out based on baseline scenarios: China-Japan-Korea FTA (Scenario 1); ASEAN+3 FTA (Scenario 2); and the RCEP (Scenario 3). The impacts of three scenarios are described in terms of real GDP, Equivalent Variation as a measure of welfare, export and import volumes, trade balance, and terms of trade. This study finds that the RCEP is to lead to an increase in real GDP of all members of the RCEP, with Korea as a winner with a highest additional economic growth of 2.43 percent, which implies that Korea is in a better position to play a leading role in promoting the RCEP.

• Journal of the Korea Convergence Society
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• v.10 no.1
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• pp.187-195
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• 2019

There is a growing emphasis on objective and quantified performance measurement methodologies for the interactions that occur within modern companies. This is due to the importance of establishing and practicing future-oriented strategies by estimating the present value of the company and the current energy status through objective evaluation of the company. Therefore, the selection of KPI as a performance index using BSC (Balance Scorecard), which is a recent objective performance measurement methodology, has become very important. Although many studies on existing KPIs have been made in various industries, KPI studies on SI companies have been insufficient. This study focuses on finding KPIs applicable to SI companies. The study on the KPI design system according to general strategy of SI companies and the development of methodology and evaluation index according to index development for each group were carried out and the weighting methodology according to each evaluation index was presented.

• Journal of the Korea Convergence Society
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• v.10 no.2
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• pp.269-276
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• 2019

The purpose of this study was to investigate the publication trends of children and adolescents' smoking-related researches published in Korean academic journals. Three hundred fifty papers published until 2018 were analyzed by focusing on the publication year, research participants, research themes and research methods. As a result, smoking-related research on children and adolescents increased sharply from 1995 to 2000, and the trend continued. The main research participants were general children and adolescents and the most frequently studied themes were 'Associated Factors,' 'Intervention,' 'Prevalence,' 'Prevention,' 'Characteristics,' 'Law and Policies,' 'Scales,' 'Review and Theories' respectively. The most frequently used research method was the quantitative method. Moreover, the most common data gathering method was using questionnaires, and the number of papers which used panel data was gradually increasing. Future studies were suggested to explore a broader range of themes, and a balanced research approach was also recommended using both qualitative and mixed methods.

• The Journal of the Korea Contents Association
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• v.19 no.8
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• pp.483-489
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• 2019

Recently, various media such as broadcasting, movies, and mobile converge with game elements, expanding the contents and expanding the area. This study focuses on the gamification convergence contents. Among them, we examine the case of mobile application live quiz show by applying the formal elements of the game mentioned by Tracy Fullerton. The elements have all the formal elements of the game, which led to the conclusion that they lead the audience to immersion based on the play characteristics of the game. This can be attributed to the elements of the game that have penetrated into the contents, and it can be reinterpreted, and the directions of new contents can be presented, which is industrially, culturally and academically significant. This study focuses on the industrial and cultural achievements created by contents, and plans and prospects new content that balances play and usefulness.

• The Journal of the Korea Contents Association
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• v.18 no.11
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• pp.236-249
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• 2018

The purpose of this study is to examine the effects of educational activities based on oriental mythology on young children's creativity and personality. A total of 14 sessions were applied to 36 children (18 experimental group and 18 control group). For this study, myths in Shan-hai jing, The Classic of Mountains and Seas), which is the origin of oriental mythology, were used as basic data of class activities and developed to experimental groups. The collected data were analyzed using SPSS 21.0 statistical program and covariance analysis (ANCOVA) was conducted with covariance score of the group after the activity. The results of this study were as follows: First, integrated educational activities using oriental mythology had a positive effect on all children's creativity and all sub-factors. Second, integrated educational activities using Oriental mythology have a positive effect on children's personality. The expansion and transformation of educational texts to oriental mythology is not only helpful for young children's creativity and personality development, but also enables them to experience cultural balance through their new understanding of the Orient.

• Journal of The Korean Society of Integrative Medicine
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• v.7 no.2
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• pp.49-57
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• 2019

Purpose: This study aimed to investigate the application of temperature to balance the training by observing the effect of sensory changes in the foot sole area on dynamic equilibrium ability through change in the sole temperature. Methods: Participants (n=49), who were selected as a certain standard, applied cold and hot packs for ten minutes at two-week intervals, and the laboratory's internal temperature was maintained at $25^{\circ}C$. The subjects were measured before and after the cold and hot applications in the stable condition with bare feet. Before each experiment applied the cold and hot packs, the balance ability of the ordinary temperature was measured once by conducting a limit of stability test using Biorescue, and the changes in balance ability were observed by measuring once after applying the temperature to the foot sole by means of the ice pack and the hot pack. Results: The results of the dynamic balance test, both before and after the temperature application, were compared, and it was confirmed that the moving area before and after cold application decreased significantly, and the moving area before and after application was not significantly different. The mean of pre-post area differences was found to have decreased at a statistically significant rate in the forward, backward, rightward, leftward, and total areas for the group that received the cold application compared to the group that received the hot application. Conclusion: These findings showed that cold application to the foot sole decreased dynamic balance. There was no significant difference in the dynamic balance ability both before and after the hot application to the foot sole, so it is difficult to conclude that the hot application affected dynamic balance.

• Journal of The Korean Society of Integrative Medicine
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• v.7 no.3
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• pp.71-83
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• 2019

Purpose: This meta-analysis aimed to analyze to the effects of aquatic exercise programs in children with cerebral palsy and identify directions for future research. Methods: A systematic search based on the PRISMA guidelines was undertaken for studies conducted between 2006 and 2018 on aquatic exercise programs in children with cerebral palsy. A total of 10 studies were selected according to the inclusion criteria. The methodological quality was assessed using the Risk of Bias Tool for Randomized Controlled Trials (RoB) and Risk-of-Bias Assessment Tool for Non-randomized Studies (RoBANS). A meta-analysis software (CMA 3.0) was used to calculate the mean effect size, effect size by intervention (Halliwick and Watsu Aquatic methods), and effect size by outcome. Results: The mean effect size was 0.457. The effect size by intervention was largest for the Halliwick method, followed by the Watsu method. The effect size by outcome was largest for range of motion, followed by the gross motor function measure, the Pediatric Berg Balance Scale, and the Modified Ashworth Scale. Meta-regression analysis showed effect size increased when sample size, number of sessions, and length of sessions increased. Conclusion: The results show that aquatic exercise programs have a positive effect on children with cerebral palsy. Therefore, it is necessary to develop a guideline that recommends the appropriate intervention and the identifies the direction of future studies on aquatic exercise programs.

• Journal of The Korean Society of Integrative Medicine
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• v.9 no.2
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• pp.1-12
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• 2021

Purpose : We aimed to determine whether improvements in balance, gait, and motor function were different when the same exercise was performed, with and without mirror therapy, by patients with subacute stroke using the affected and unaffected lower limbs. Methods : Eight patients with subacute stroke were randomly divided into experimental groups 1, 2 and the control group. A mirror therapy program was performed with group 1 using the unaffected lower limb and group 2 the affected lower limb. The exercise lasted 30 min per session, five times weekly, for 4 weeks. The control group did not perform the exercises. BT-4, BBS, POMA, 10MWT, and BRS were used to evaluate balance, gait, and motor function before and after the intervention. Results : Post-intervention analysis showed that all three groups had higher BBS scores. After training, the postural sway in groups 1 and 2 decreased in the post eye opened and closed positions; that of the control group increased. The scores of two subjects in group 1 increased by 4 and 5 points in POMA, resulting in significant changes compared to those in the other groups. No group showed significant results in 10MWT. BRS improved in all subjects in group 1 from BRS 2 to 1 and in only one subject in group 2 there was no change in the control group. Conclusion : Static and dynamic balance and significant results are noted in POMA, BBS, but not gait velocity. Therefore, mirror therapy seems to show a positive change in subacute patients, but the research results are not clear and the difference between groups is unknown due to the small number of subjects. The effects of mirror therapy and exercise therapy should be compared using more subjects in future.