• The Transactions of the Korean Institute of Power Electronics
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• v.6 no.1
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• pp.34-42
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• 2001

A battery is the device that transforms the chemical energy into the direct-current electrical energy directly without a mechanical process. Unit cells are connected in series to obtain the required voltage, while being connected in parallel to organize capacity for load current and to decrease the internal resistance for corresponding the sudden shift of the load current. Because the voltage droop down in one set of battery is faster than in tow one, it amy result in the low efficiency of power converter with the voltage drop and cause the system shutdown. However, when the system being driven in parallel, a circular-current can be generated. The changing current differs in each set of battery because the system including batteries, rectifiers and loads is connected in parallel and it makes the charge voltage constant. It is shown that, as a result the new batteries are heated by over-charge and over-discharge, and the over charge current increases rust of the positive grid and consequently shortens the lifetime of the new batteries. The difference between the new batteries and old ones is the amount of internal resistance. In this paper, we can detect the unbalance current using the micro-processor and achieve the balance current by adjusting resistance of each set. The internal resistance of each set becomes constant and the current of charge and discharge comes to be balanced by inserting the external resistance into the system and calculating the change of internal resistance.

• Journal of the Korea Convergence Society
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• v.9 no.3
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• pp.249-256
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• 2018

This study aims to explore efficient foreign language learning paradigm with a focus on reading fluency and accuracy. From a perspective of language acquisition in the foreign language context, the priority in the L2 learning between accuracy and fluency has been a very important issue. Fluency becomes an important issue due to many researchers' interests in the L1 and L2 classroom. Although both accuracy and fluency are crucial, the paradigm shift from fluency to accuracy is necessary in the foreign language teaching. In this context, as an alternative methodology for L2 learners' fluency, the extensive reading approach is provided. A number of studies have suggested that extensive reading program could lead to improvement of L2 learners' reading rate and is an effective approach to improving general language proficiency.

• Korean Journal of Microbiology
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• v.33 no.4
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• pp.252-256
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• 1997

The white rot fungus Coriolus hiysutus decolorized several recalcitrant dyes. Four different types of dyes, including azo, triphenyl methane, heterocyclic, and polymeric dye, were treated by the mycelial preparation. Triphenyl methane dye, bromophenol blue lost over 95% of its color. Congo red and Poly R-478 were decolorized less than bromophenol blue, 57 and 55%, respectively. However, heterocyclic dye, methylene blue was not decolorized significantly and only red shift was observed. Extracellular laccase and peroxidase activities were appeared maximally in high level of dye decolorization media. In electrophoretic experiments, common active bands of laccase and peroxidase were found in all dye decolorized medium. These results indicated that the culture conditions which yield high levels of laccase and peroxidase activity lead to high levels of dye decolorization, and these two enzymes might be play an important roles in dye decolorization.

• Molecules and Cells
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• v.43 no.9
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• pp.793-803
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• 2020

Myeloid-derived suppressor cells (MDSCs) promote tumour progression by contributing to angiogenesis, immunosuppression, and immunotherapy resistance. Although recent studies have shown that microRNAs (miRNAs) can promote the expansion of MDSCs in the tumour environment, the mechanisms involved in this process are largely unknown. Here, we report that microRNA 449c (miR-449c) expression was upregulated in myeloid progenitor cells upon activation of C-X-C motif chemokine receptor 2 (CXCR2) under tumour conditions. MiR-449c upregulation increased the generation of monocytic MDSCs (mo-MDSCs). The increased expression of miR-449c could target STAT6 mRNA in myeloid progenitor cells to shift the differentiation balance of myeloid progenitor cells and lead to an enhancement of the mo-MDSCs population in the tumour environment. Thus, our results demonstrate that the miR-449c/STAT6 axis is involved in the expansion of mo-MDSCs from myeloid progenitor cells upon activation of CXCR2, and thus, inhibition of miR-449c/STAT6 signalling may help to attenuate tumour progression.

• Korean Medical Education Review
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• v.18 no.2
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• pp.58-64
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• 2016

The birth of the scientific revolution, brought forth by Vesalius and Copernicus in 1543, marked the beginning of a new age. However, the changes such as treatment effectiveness, survival rate, prevalence of specific diseases, etc. had not yet become clear during the 16th century. In the early 17th century, Boerhaave emphasized bedside teaching and practice. His attitude influenced numerous students and educators, so many medical students visited hospital wards where he worked. From the late 18th to 19th centuries, Jenner's smallpox vaccination, Pasteur's anthrax and rabies vaccinations, and Koch's four postulates used to detect pathogens were developed using the scientific research method, which initiated big changes for medicine. Flexner, credited for reporting the new medical education system, adopted scientific medicine. He believed medical students must study basic medical science since it could be the foundation of clinical medicine and lead to a revolution in the field. He proposed a new medical curriculum composed of two-years of basic medicine and two-years of clinical medicine, which has been used more than 100 years. During the late 20th century, bedside teaching rounds decreased gradually as scientific medicine has become popular. Many medical educators in many articles have proposed bedside education as an effective method for medical learning. Despite the advent of the age of artificial intelligence and the changing of medical environments in the near future, bedside education will be more useful and important for medical students, educators, and patients as it is a traditional method and essential for patients who desire a more personal approach.

• The Journal of the Korea Contents Association
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• v.21 no.9
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• pp.666-683
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• 2021

Organizational humor is generally perceived as a phenomenon that helps to develop happy feelings and positive workspace. While humor may affect organizational members in diverse ways, the ambiguous nature of humor may create uncertainty and unexpected outcomes. In particular, humor used by and between organizational members in diverse organizational situations (including physical office context and work hours) may influence individual's perception of space. Findings suggest that humor interaction acts as a form of deviant behavior that diverts from work. This momentary non-work event (humor) may serve as a ritual to influence individual's perception of space, from work to personal domain, and vice versa. The quality of interpersonal relationships between the communicators may also be influenced by humor. This shift in the nature of interaction (from work to non-work) may lead to blurring boundaries of work and work experiences. Therefore, organizational humor may provide insights into how workers interact, perceive, and manage work and personal space within organizational contexts.

• Asian Journal of Innovation and Policy
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• v.10 no.2
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• pp.195-211
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• 2021

This paper measures the economic impacts of the U.S. port investment strategies coping with the Panama Canal expansion. Using secondary import data, negative and positive estimates of the impacts were presented in this study. Reduced port activities into the West Coast Customs Districts negatively affect transportation and warehousing industries, among other effects. Still, they have simultaneous positive effects in other states from increased imports resulting from modal shifts and changes in the entry port located in the South and East coasts. This study applied the supply-driven National Interstate Economic Model that measures all interstate trade among the U.S. states to divert foreign imports from 15 Pacific Rim countries. For this purpose, the following assumption was adopted: larger ships using the canal will lead to a redirection of seaborne trade among U.S. (and other) ports and result in secondary effects, e.g., using different freight modes and regional growth spillovers. This study also accounted for the entry point change and significant port investments for foreign trade under alternative scenarios. The choice of ports for international trade depends on decisions about how to minimize multimodal delivery costs. The total direct reduction of transportation and warehousing activities associated with foreign imports in the West Coast ports was estimated at $3.3 billion, leading to total negative effects of $5.8 billion. Total positive impacts from the shift of transportation modes with the choice of an entry port and new warehousing activities for foreign imports in the selected 12 states varied. As expected, states that involved an entry port had the most prominent benefits, but Texas, New York, and New Jersey may be benefited through all the port enhancement projects in the U.S. Also, except for Transportation and Postal, and Warehousing industries, Construction is another dominant positive affected industry of the Canal expansion in the U.S.

• Journal of Convergence for Information Technology
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• v.11 no.2
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• pp.16-24
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• 2021

This paper introduces a smart aging service that helps the elderly lead a happy old age by actively utilizing IoT and AI technologies for the elderly who are increasing rapidly as they enter the aging society. In particular, we propose a future-oriented, age-friendly well-being support system that breaks away from the existing welfare concept to solve the aging problem but leads to a paradigm shift toward building a vibrant aging society by protecting from emergency and satisfying emotions. By introducing IoT and AI, it judges the life situation and emotional state from the living information of the elderly can respond to emergencies and suggest meetings as a change of mood and give an emotional comfort. Since the proposed system uses artificial intelligence techniques to determine the degree of depression when inputting information such as pulse-rate, dangerous word usage, and external communication, I think it showed the feasibility of the new concept of wellbeing support system that is totally different from conventional wellbeing concept of health-care.

• Journal of Digital Convergence
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• v.20 no.2
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• pp.107-116
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• 2022

In the Chinese workplace, the use of SNS such as Wechat and QQ for work delivery out of duty hours has become a very common phenomenon, which is also known as the "new night shift". This study is to empirically analyze the effect of work delivery using SNS out of duty hours on job performance. A questionnaire survey was conducted with 310 Chinese workplace employees. In order to verify the hypothesis, structural equation model analysis will be implemented. Analyzing the questionnaire data and receiving frequent work delivery using SNS out of duty hours will increase job stress, aggravate the conflicts between work and family, and lead to the decrease of job engagement and job performance. The study provides implications for the establishment of related theories by providing a different view form previous research results that work delivery using SNS out of duty hours will definitely improve job performance. In addition, in future studies, it will be necessary to analyze the effect of the moderating effect in converging these conflicting views.

• Journal of Fashion Business
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• v.26 no.1
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• pp.1-15
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• 2022

Digital transformation has induced changes in human life patterns; consumption patterns are also changing to digitalization. Entering the era of industry 4.0 with the 4th industrial revolution, it is important to pay attention to a new paradigm in the fashion industry, the shift from developer-centered to user-centered in the era of the 3rd industrial revolution. The meaning of storing users' changing life and consumption patterns and analyzing stored big data are linked to consumer sentiment. It is more valuable to read emotions, then develop and distribute products based on them, rather than developer-centered processes that previously started in the fashion market. An AI(Artificial Intelligence) deep learning algorithm that analyzes user emotion big data from user experience(UX) to emotion and uses the analyzed data as a source has become possible. By combining AI technology, the fashion industry can develop various new products and technologies that meet the functional and emotional aspects required by consumers and expect a sustainable user experience structure. This study analyzes clear and useful user experience in the fashion industry to derive the characteristics of AI algorithms that combine emotions and technologies reflecting users' needs and proposes methods that can be used in the fashion industry. The purpose of the study is to utilize information analysis using big data and AI algorithms so that structures that can interact with users and developers can lead to a sustainable ecosystem. Ultimately, it is meaningful to identify the direction of the optimized fashion industry through user experienced emotional fashion technology algorithms.