• International Journal of Internet, Broadcasting and Communication
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• v.16 no.2
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• pp.103-111
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• 2024

We address the problematic issue of blinking in residential LED lighting systems-a phenomenon that has recently become a significant concern due to voltage sags caused by high-power household appliances. To combat this, we developed a two-stage LED converter with integrated anti-blinking circuitry, specifically designed for T5 LED indirect lighting fixtures. The first stage employs a Power Factor Correction (PFC) boost circuit to enhance voltage stability by aligning the voltage and current phases, thereby minimizing power losses. The second stage, a meticulously engineered DC-DC buck converter, ensures stable lighting despite electrical fluctuations. Rigorous testing has confirmed our converter's efficacy in maintaining consistent light output without blinking, thereby substantially improving user comfort and adhering to strict standards for harmonic distortion and electromagnetic compatibility. Our breakthrough provides a robust solution to a pressing issue, marking a significant advancement in LED lighting technology.

• ETRI Journal
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• v.36 no.4
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• pp.519-527
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• 2014

An integrated multi-beam satellite and multi-cell terrestrial system is an attractive means for highly efficient communication due to the fact that the two components (satellite and terrestrial) make the most of each other's resources. In this paper, a terrestrial component reuses a satellite's resources under the control of the satellite's network management system. This allows the resource allocation for the satellite and terrestrial components to be coordinated to optimize spectral efficiency and increase overall system capacity. In such a system, the satellite resources reused in the terrestrial component may bring about severe interference, which is one of the main factors affecting system capacity. Under this consideration, the objective of this paper is to achieve an optimized resource allocation in both components in such a way as to minimize any resulting inter-component interference. The objective of the proposed scheme is to mitigate this inter-component interference by optimizing the total transmission power - the result of which can lead to an increase in capacity. The simulation results in this paper illustrate that the proposed scheme affords a more energy-efficient system to be implemented, compared to a conventional power management scheme, by allocating the bandwidth uniformly regardless of the amount of interference or traffic demand.

• Korean Journal of Community Nutrition
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• v.9 no.3
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• pp.326-332
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• 2004

The research objective was to identify the effect of various instruction media on improving students' foodservice management competencies and for increasing class satisfaction. The research involved a comparison of two student groups. One group consisted of students who attended a lecture-based food purchasing class (Group A). The other group was students who attended the same class, and who also used various media as well as receiving the lecture (Group B). The results were as follows: 1) After a 16 week program, Group B perceived their procurement management competencies to be higher than those of Group A, especially in setting up purchasing goals, marketing research, and using computer systems for procurement; 2) In terms of class satisfaction, it was also observed that Group B was more satisfied with food purchasing class than was Group A. Group B gave high scores, especially in effective utilization of media, increasing motivation, and understanding; 3) Group B perceived that various instruction media was helpful for developing their procurement management competencies. Respondents evaluated the usefulness of media in the following order: using Power Point watching videos, visiting web-sites for food purchasing class, and surfing the World Wide Web. The results of the research show that using various instruction media for food purchasing classes would improve students' foodservice management competencies. Therefore, instructors who teach foodservice management related courses should consider developing teaching strategies that apply various instruction media for students to enhance their foodservice management competencies and to increase class satisfaction.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.1
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• pp.192-196
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• 2010

Due to a development of a modem technology as Power Line Communication(PLC) over 200 Mbps, the high-speed multi-media data trasmission could be currently possible. The strength of the PLC has no more additional wiring work. PLC has also possible to high quality data transmission with currently electrical cable. It has a various strong point campare with existing wire and wireless communication technologies. In This paper we develop a high quality media transmitter-receiver based on merging the HomePlug AV, which is 200 Mbps class PLC technology and HDMI Interface technology. The video function was used for the VEDEO TEST GENERATOR in order to a property valuation. Smart Live 6 software were used for the assessment of audio property. As the result of measurement of the HD class images by capturing from the receiver of the PLC, the quality of images couldn't be confirm any deterioration, which has compared with original reflections. In case of audio part as the result of confirmation of the Phase, Magnitude, it has been confirmed that over 90% of nomal transmition and receiving of acoustic signal. It can be possible to have HD class Media service through the PLC.

• Journal of Electrochemical Science and Technology
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• v.5 no.3
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• pp.73-81
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• 2014

This paper describes the continuous flow operation of membraneless sodium perborate fuel cell using acid/alkaline bipolar electrolyte. Here, hydrazine is used as a fuel and sodium perborate is used as an oxidant under Alkaline-acid media configuration. Sodium perborate affords hydrogen peroxide in aqueous medium. In our operation, the laminar flow based microfluidic membranleless fuel cell achieved a maximum power density of $27.2mW\;cm^{-2}$ when using alkaline hydrazine as the anolyte and acidic perborate as the catholyte at room temperature with a fuel mixture flow rate of $0.3mL\;min^{-1}$. The simple planar structured membraneless sodium perborate fuel cell enables high design flexibility and easy integration of the microscale fuel cell into actual microfluidic systems and portable power applications.

• Proceedings of the KIEE Conference
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• 2000.07b
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• pp.781-783
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• 2000

In developing the assemble HEPA(High Efficiency Particulate Air) Filter, the main frame and sub frame can be easily assembled and disassembled and tightly sealed. The sub frame(included Media) will be made of the manageable material. so it will be easily compacted with the spent filter compactor. It does not take a lot of time for disassembling the spent filter. The main frame can be recycled and the volume of the spent filter is reduced, so the cost for treating the radioactive waste is reduce. And the changing costs can be reduced, because the cost of the media is lower than the filter.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.8 no.11
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• pp.31-40
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• 2018

This paper studies how marriage migrants are being depicted in Korean Cinema. In the recent years, the foreign population in South Korea has been increasing and so has done the presence of migrant minorities in media, including cinema. This study discusses that korean cinema shows dominant ideologies of power in Korean society where marriage migrants are located at the bottom. Five films were analyzed and from this analysis five frames were extracted. Marriage migrants are frequently depicted as subordinated or powerless, they are usually women in the role of wives, mothers, and daughters-in-law, they are treated as ethnic others, sexualized others or commodities. Consequently, their relationships with Korean nationals are formed by power relations. Moreover, Korean national who do establish some sort of intimate relationship with the marriage migrants are represented as people in the margins of Korean society. In this way, it is reinforced the social position of marriage migrants as outsiders in the Korean society.

• Smart Media Journal
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• v.12 no.5
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• pp.122-122
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• 2023

• Korean journal of communication and information
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• v.59
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• pp.71-91
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• 2012

Gun-Ho Song had been selected as 'the most respected person' in a survey targeting journalists. While being a journalist, Gun-Ho Song had directly experienced that the press submitted to government suppression and became commercialized receiving government benefits. In 1975, when Dong-A Ilbo(Daily News) submitted to the government suppression and conducted a mass of discharge of journalists, he felt responsibility and left the newspaper company. After that, he criticized more sharply the media subordinated to the power and capital. The core of Gun Ho Song's thought of the press is that the media should be independent from the power and capital contributing to nationalism and democracy. Also, he insisted that journalists should equip with historical consciousness and social scientific knowledge beyond roles like skilled workers. His idea of the press is still valid in the current media situation showing that journalists become skilled workers and independence of the press is risky. Looking into his activity and idea of the press can help seek for the right attitude of journalists and right roles of the media in the change of media environment.

• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.483-485
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• 2000

This paper presents the operation technology and the remote monitoring system of distribution pole transformer. Especially, this system uses CDMA wireless data communication network as media which is serviced on a national scale. It has four major components such as sensor for measuring the secondary voltage and currents of distribution transformer, CDMA wireless modem for data modulating/demodulating, communication media for sending/receiving of data, and PC server for monitoring the results of sensing or computing information. This paper also describes the configuration of each component's functions with its development process.