• Journal of the Microelectronics and Packaging Society
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• v.25 no.4
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• pp.17-23
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• 2018

Recently, electric semiconductors became an issue because of efficient use of energy and compaction of electronics. Silicon electric semiconductors are difficult to put into it because of its physical limitations. Hence, the study of WBG (Wideband Gap) semiconductors like SiC and GaN began. These devices received attention because it can be miniaturized and worked at high temperatures over $300^{\circ}C$. WBG MOSFET electric semiconductors can show performance like silicon IGBT. This can solve the current problem of IGBT tail. The current study shows the technical principles and issues related to SiC and GaN power semiconductors. WBG devices can achieve high performance compared to silicon, but its performance can't be fully utilized because of lack in bonding technology. Therefore, this review introduces research on WBG devices and their packaging issues.

• Transactions of the Korean hydrogen and new energy society
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• v.31 no.6
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• pp.530-545
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• 2020

This paper reviews and summarizes the fuel-cell-related studies those have been recently published in major Korean Citation Index journals, aiming at analyzing the research trend in fuel cell technologies. Six major journals are selected for the literature survey; 57 papers are chosen for the detailed analysis through a screening examination on the total 1,040 papers published during between 2018 and 2020. Papers are classified into six technical categories, such as i) electrode, ii) electrolyte, iii) bipolar plate and stack, iv) fuel cell system, v) balance of plant, and vi) diagnosis-related studies, and summarized by the experts in the relevant area. Through this paper, we provide a comprehensive review on the recent trends and progress in fuel-cell-related research work in Korea.

• Journal of the Korean Society of Mechanical Technology
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• v.20 no.6
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• pp.879-885
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• 2018

Precedent research and development of personal armor and anti-stab wearing system has been conducted since 2018 as a part of the government-affiliated cooperative development project to create the best utilization of present technology and achievement according to the civil and military technical cooperation project promotion law. At present, the armor system operated by the ROK(Republic of Korea) military, the police, and the marine police is utilizing only basic armor using armor vests and plates. Therefore it is necessary to develop the personal armor and anti-stab wearing system which is suitable for various tasks in army with maximum protection capability. In this paper, we analyzed the study about international technologies, market trends of the developed countries and scope of research, utilization plan, R&D results for the best armor and anti-stab wearing system development.

• Journal of the Microelectronics and Packaging Society
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• v.28 no.1
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• pp.21-29
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• 2021

Recently, semiconductor chips and electronic components are increasingly being used in IT devices such as wearable watches, autonomous vehicles, and smart phones. As a result, there is a growing concern about device malfunctions that may occur due to electromagnetic interference being entangled with each other. In particular, electromagnetic wave emissions from wearable or flexible smart devices have detrimental effects on human health. Therefore, flexible and transparent electromagnetic interference (EMI) shielding materials and films with high optical transmittance and outstanding shielding effectiveness have been gaining more attention. The EMI shielding films for flexible and transparent electronic devices must exhibit high shielding effectiveness, high optical transmittance, high flexibility, ultrathin and excellent durability. Meanwhile, in order to prepare this EMI shielding films, many materials have been developed, and results regarding excellent EMI shielding performance of a new materials such as carbon nano tube (CNT), graphene, Ag nano wire and MXene have recently been reported. Thus, in this paper, we review the latest research results to EMI shielding films for flexible and transparent device using the new materials.

• International Journal of Computer Science & Network Security
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• v.22 no.5
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• pp.55-60
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• 2022

Acceleration of the pace of life, increasing the amount of information, the emergence of "clip way of thinking" as a phenomenon has led to the problem of choosing forms of presentation of educational materials to students. One of the ways to solve this problem is to use the means of visualization of information flow, forasmuch as the thinking of modern youth is more effective in perceiving visual images than verbal means. The purpose of the research is to prove the effectiveness of the use of visualization in the process of teaching Ukrainian as a foreign language to students with clip way of thinking. The following methods have been used, namely: analysis, synthesis, comparison, systematization and generalization of scientific literature; testing and surveys; pedagogical experiment; quantitative and qualitative analysis of data, interpretation and generalization of the research results. The essence of visualization means has been revealed; the expediency of their use in the methodology of teaching foreign students the Ukrainian language has been substantiated. It has been proven that the role of Ukrainian teachers lies in taking into account all new trends in teaching, integrating computer perception of information by foreign students into teaching technology and using cognitive visualization in order to intensify the learning process.

• Clinics in Shoulder and Elbow
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• v.25 no.1
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• pp.42-48
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• 2022

Background: Total shoulder arthroplasty (TSA) has been demonstrated to be an effective treatment for multiple shoulder pathologies. The purpose of our study was to compare the relative value units (RVUs) per minute of surgical time for primary and revision TSA. Methods: The American College of Surgeons National Surgical Quality Improvement Program database was queried to identify patients that underwent primary TSA, one-component revision TSA, and two-component revision TSA between January 1, 2015 and December 31, 2017 using current procedure terminology codes. RVUs were divided by mean operative time for each procedure to determine the amount of revenue generated per minute. Rates were compared between the groups using a one-way analysis of variance with post-hoc Tukey test. Statistical significance was set at p<0.05. Results: When dividing compensation by surgical time, we found that two-component revision generated more compensation per minute compared to primary TSA (0.284±0.114 vs. 0.239±0.278 RVU per minute or $10.25±$4.11 vs. $8.64±$10.05 per minute, respectively; p=0.001). Conclusions: The relative value of revision TSA procedures is weighted to account for the increased technical challenges and time associated with these procedures. This study confirms that reimbursement is higher for revision TSA compared to primary TSA.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.1
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• pp.105-112
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• 2023

We analyze the global market for flexible electronic circuits, technical considerations, and analyze the market for application areas and regions. In the market analysis of the application field, the display field has the greatest influence in terms of market size and annual growth rate, and the OLE D lighting market size is expected to grow by nearly 50% in 2026. The multilayer flexible electronics, which dependently requires the semiconductor technology, has a larger market size than other structures and its growth rate is relatively large, leading the market and will be further analyzed in depth. The market size of multilayer flexible electronics applied to display field is expected to show an annual growth rate of 21.1% from $2.7 billion in 2017 to $9.8 billion in 2026, and the OLED market is expected to grow by 75.2% during the same periods. Recently, as electronic products have been miniaturized and advanced, and robust installation in a small space is required, companies that preoccupy multilayer structure or rigid flexible electronic circuit technology have an advantage in competitiveness, so many companies are trying to obtain this technology. These efforts are systematically supported by many countries because they can achieve mutual growth by strengthening the competitiveness of the application field and the same industry. In the case of Korea, a support system is established, but it is required to expand and activate it, and to localize manufacturing equipment and materials.

• Microbiology and Biotechnology Letters
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• v.50 no.4
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• pp.465-476
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• 2022

The importance of beneficial microorganisms, particularly probiotics, that coexist in the human body, is being increasingly recognized. Probiotics are representative health functional foods that provide health benefits to humans through the production of various metabolites, including short-chain fatty acids. However, the health benefits are strain-specific, and the use of each probiotic strain should follow guidelines that assure its safety. Accurate identification of the strain should be managed through genetic and phenotypic analyses of the strain. Besides, the functionality of probiotics should be disclosed in vitro and in vivo so that they can be used as legal functional ingredients (i.e., individual standards). In this review, we deal with the guidelines, including the technical factors related to probiotic strains. The common health effects of probiotic strains include proliferation of beneficial bacteria, control of harmful bacteria, and facilitation of bowel activities. Probiotics with various functionalities (e.g., body fat and cholesterol reduction, vaginal health, and improvement of skin's immune system) have been investigated as "individual standards of raw materials for health functional foods" provided by MFDS. In the future, various biotechnologies including synthetic biology can be applied to produce customized probiotics to improve human health.

• Journal of the Korea Society of Computer and Information
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• v.28 no.8
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• pp.59-66
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• 2023

The Golden Cross is commonly seen as a buy signal in financial markets, but its reliability for predicting stock price movements is limited due to market volatility. This paper introduces a time-invariant approach that considers the Golden Cross as a singular event. Utilizing LSTM neural networks, we forecast significant stock price changes following a Golden Cross occurrence. By comparing our approach with traditional time series analysis and using a confusion matrix for classification, we demonstrate its effectiveness in predicting post-event stock price trends. To conclude, this study proposes a model with a precision of 83%. By utilizing the model, investors can alleviate potential losses, rather than making buy decisions under all circumstances following a Golden Cross event.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.515-515
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• 2022

Climate change is strongly threatening the performance of agricultural reservoirs, which are instrumental in ensuring uninterrupted water supplies for rice cultivation in Korea. In this study, various performance indices were derived and overall sustainability of the 400 agricultural reservoirs was evaluated in the context of climate change trends during 1973-2017. Rice crop evapotranspiration, irrigation water requirements, runoff generation in the upstream watershed, and volumetric evaporation losses were plugged into a water balance model to simulate the reservoir operation during the study period. Resilience, reliability, and vulnerability are the three main indicators of reservoir performance, and these were combined into a single sustainability metric to define the overall system credibility. Historical climate data analysis confirmed that the country is facing a gradual warming shift, particularly in the central and southern agricultural regions. Although annual cumulative rainfall increased over the last 45 years, uneven monthly rainfall distribution during the dry and wet seasons also exacerbated the severity and frequency of droughts/floods. For approximately 85% of the selected reservoirs, the sustainability ranged between 0.35 to 0.77, and this range narrowed sharply with time, particularly for the reservoirs located in the western and southern coast regions. The study outcomes could help in developing the acceptable ranges of the performance indices and implementing appropriate policy and technical interventions for improving the sustainability of reservoirs with unacceptable ranges of the performance indices.