• 전력전자학회논문지
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• 제26권3호
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• pp.176-182
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• 2021

This research proposes a high-frequency circuit that can accurately predict the differential mode noise of single-phase inverters at the circuit design stage. Proposed single-phase inverter high frequency circuit in the work is a form in which harmonic impedance components are added to the basic single-phase inverter circuit configuration. For accurate noise prediction, parasitic components present in each part of the differential noise path were extracted. Impedance was extracted using a network analyzer and Q3D in the measurement range of 150 kHz to 30 MHz. A high-frequency circuit model was completed by applying the measured values. Simulations and experiments were conducted to confirm the validity of the high-frequency circuit. As a result, we were able to predict the resonance point of the differential mode voltage extracted as an experimental value with a high-frequency circuit model within an approximately 10% error. Through this outcome, we could verify that differential mode noise can be accurately predicted using the proposed model of the high-frequency circuit without a separate test bench for noise measurement.

• Elastomers and Composites
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• 제56권1호
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• pp.20-31
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• 2021

There is an increasing demand for the rolling resistance reduction in truck bus radial (TBR) tires in the tire industry. In TBR tires, natural rubber is used as a base polymer to prevent wear and satisfy required physical properties (cut and chip). A binary filler system (silica and carbon black) is used to balance the durability of the tire and rolling resistance performance. In this study, natural rubber (NR) compounds applied with a binary filler system were manufactured at different cure temperatures for vulcanizate structure analysis. The vulcanizate structures were categorized into carbon black bound rubber, silica silane rubber network, and chemical crosslink density by sulfur. Regardless of the cure temperature, the cross-link density per unit content of carbon black had a greater effect on the properties than silica due to affinity with NR. The relationship analysis between the mechanical, viscoelastic properties with vulcanizate structure could be a guideline for manufacturing practical TBR compounds.

• 한국의류산업학회지
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• 제23권6호
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• pp.790-798
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• 2021

With digital technology innovation, increased data access and mobile network use by consumers, products and services are changing toward pursuing differentiated values for personalization, and personalized markets are rapidly emerging in the fashion industry. This study aims to identify trends in digital customized automation technology by deriving types of digital customizing and analyzing cases by type, and to present directions for the development of digital customizing processes and the use of technology in the future. As a research method, a literature study for a theoretical background, a case study for classification and analysis of types was conducted. The results of the study are as follows. The types of digital customizing can be classified into three types: 'cooperative customization', 'selective composition and combination', 'transparent suggestion', and automation technologies shown in each type include 3D printing, 3D virtual clothing, robot mannequin, human automatic measurement program, AR-based fitting service, big data, and AI-based curation function. With the development of digital automation technology, the fashion industry environment is also changing from existing manufacturing-oriented to consumer-oriented, and the production process is rapidly changing with IT and artificial intelligence-based automation technology. The results of this study hope that digital customized automation technology will meet various needs of personalization and customization and present the future direction of digital fashion technology, where fashion brands will expand based on the spread of digital technology.

• 한국인터넷방송통신학회논문지
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• 제22권2호
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• pp.135-141
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• 2022

연구개발 기획 단계에서부터 종료까지 연구개발 전반에 있어 연구 과정과 성과를 기록으로 보존하는 것은 연구자의 중요한 역할이다. 이는 연구개발 과정 및 결과의 객관성을 뒷받침하는 근거로 활용할 수 있다. 연구노트 작성은 연구윤리, 기록관리, 지식재산권 보호, 연구 결과 보호의 측면에서 그 필요성이 제기되고 있으며, 「국가연구개발혁신법」에 따라 폐쇄망을 사용하는 연구개발 기관 환경에 적합한 전자연구노트 시스템을 구축하여 운영하고자 계획하였다. 이에 본 논문에서는 정부 출연기관에 운영되고 있는 연구노트의 제도적·실무적 관리 방안 조사를 진행한 결과를 기술하였으며, 조사 결과를 토대로 폐쇄망을 사용하는 업무망 환경에 적합한 전자연구노트 시스템 구축 및 운영 방안을 기술하였다.

• International journal of advanced smart convergence
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• 제12권3호
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• pp.149-156
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• 2023

Joint research on software, electronic engineering, computer engineering, and financial engineering and the use of ICT knowledge through network formation play an important role in strengthening science and technology-based innovation capabilities and facilitating the development and production process of products using new technologies. For the purpose of this study, I would like to strategically propose ICT specialized education in the 4th industrial revolution. To this end, the ICT specialization model, ICT specialization strategy analysis, and ICT specialization operation and effect were explored to establish ICT specialization strategies centered on software, electronic engineering, computer engineering, and financial engineering in the era of super-intelligence, hyper-connected, and hyper-convergence. Secondly, a roadmap for detailed promotion tasks related to efficient ICT characterization based on core strategies, detailed promotion tasks, and programs was proposed, focusing on talent related to ICT characterization. Thirdly, we would like to propose a reorganization of the academic structure and organization related to ICT characterization. Finally, we would like to propose the establishment of a future-oriented education system related to ICT specialization based on the advanced education and research environment.

• International Journal of Internet, Broadcasting and Communication
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• 제15권3호
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• pp.73-81
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• 2023

Globalized cities are currently showing changes due to autonomous driving (AD). It is also maximizing globalization connections in cities where autonomous mobility is as complex as AD. The purpose of this study is to reveal that cities that realize AD and mobility will grow into globalized cities. Several cities, including New York and Shanghai, have attempted and are in progress, but failed cities are increasing. Although the technology of AD and the trust of citizens are prioritized, the city that has built the city's infrastructure is expected to be a city that has succeeded in AD. This is because commercialized cities or AVs will become hubs for mobility globalization, excluding rapid climate change or AV companies, and empirical analysis has been conducted that if AVs fail in metropolitan New York due to urban complexity (population density), urban economy size (GRDP), patents, number of consumers, infrastructure public EV chargers, and road quality. It examines whether the realization of AD by region and country affects overall national innovation. As a result, even if AV succeeds in large cities such as New York, Seoul, which has a higher population density (complexity), has a negative meaning, and a more similar Tokyo has a positive meaning. It can be seen that regional research on AV should also be prioritized in large cities such as Shanghai. This means that in order for AV to be realized in each city, the construction of AI infrastructure data must be actively changed to establish globalization of cities for economic growth as autonomous mobility.

• Asia Marketing Journal
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• 제17권1호
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• pp.69-95
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• 2015

This paper examines a highly used social networking site (SNS) by studying the behavior of more than 11 million members over a 20 month period. The importance of the most highly active members to the overall network is demonstrated by the significant fraction of total visits by extremely active members in a given period but such members have surprisingly short lifespans (an average of only 2.5 months) as social hubs. We form and test a number of hypotheses concerning these social hubs and the determinants of their lifespan. We find that the speed of achieving social hub status increases the lifespan of a social hub. The norm of reciprocity is strongly confirmed to be present in the social hub population as visits are reciprocated. We also find that increasing local dominance in terms of activities over neighboring agents leads to a longer lifespan of a social hub. Contrary to expectations, local clustering in the vicinity of social hubs is smaller (rather than larger) than overall clustering. We discuss managerial implications in the paper.

• 무역학회지
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• 제45권3호
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• pp.1-19
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• 2020

Recently, traditional trade in the global trade market has stagnated in the aftermath of the US-China trade war and the coronavirus (COVID-19) pandemic. However, the global e-commerce market is growing rapidly, presenting a new opportunity for exports. To examine the effect of an online matching and logistics system on reverse overseas direct purchase and the mediating effect of reliability, this study conducted a questionnaire survey on 320 employees in a Korean trade company from March 10 to April 30, 2018. The study model's goodness of fit was tested, and an analysis was performed using the AMOS statistical package. The online matching and logistics system were found to have a positive effect on reverse overseas direct purchase. Furthermore, results revealed that while a country's reliability mediated online matching and reverse overseas direct purchase, it did not mediate the logistics system. These results mean that online matching is affected by a country's reliability in overseas consumers' buying decision process. This study provides implications for the future directions of export companies and national policies to promote reverse overseas direct purchase. Future research including more countries and companies would be able to make further contributions toward the development of the Korean cross-border e-commerce industry.

• Asia pacific journal of information systems
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• 제30권3호
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• pp.513-531
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• 2020

Online Word-of-Mouth communication, or eWOM, has dramatically changed the way people network, interact, and share knowledge. Studies have examined why consumers choose to share knowledge online, especially online product reviews, as well as the motivations of individuals to share product ideas online. However, the role of gender in shaping the motivation and types of knowledge shared online has been given little consideration. Using concepts from Social Exchange Theory and the Theory of Reasoned Action, we address this research gap by developing and testing a model of gender's influence on knowledge sharing in a social media context. A PLS analysis of survey data from 257 students indicates that reputation, altruism, and subjective norms are key motivators for knowledge sharing intention in social media. More importantly, that gender plays a moderating role within the motivation-knowledge sharing relationship. We also find that subjective norms have a greater impact on knowledge sharing with women than with men. Collectively, our research results highlight individualized factors for improving customer participation in external facing social media for marketing and product innovation.

• International Journal of Internet, Broadcasting and Communication
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• 제16권2호
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• pp.59-67
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• 2024

Current straw mushroom farming in countries with large rice growing areas has great development potential, and was once considered a way to generate additional income and reduce poverty in rural areas. However, currently most people still grow mushrooms using traditional processes, leading to low productivity and unguaranteed output quality. Currently, due to climate change and unusual weather changes, people tend to switch to growing straw mushrooms indoors. In the process of growing straw mushrooms indoors, the design of an automatic control and monitoring system is very important to ensure the growing process is carried out effectively and achieves high yields. In this paper, we propose a system that can automatically control and monitor the humidity and temperature of the indoor straw mushroom growing process and other parameters that can be monitored through a network system using Internet of Things. The control algorithm automatically adjusts the grow house equipment based on feedback from sensors to maintain an optimal environment for growing straw mushrooms. Experimental results show that the straw mushroom growing system with automatically controlled and monitored environmental parameters helps improve efficiency, reduce costs and increase the sustainability of the current straw mushroom growing industry.