• Journal of Korean Society of Environmental Engineers
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• v.31 no.9
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• pp.793-802
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• 2009

Adsorption properties were estimated for the organic silicon compounds (siloxanes) in an actual landfill gas (LFG) using adsorbents such as coconut activated carbon, coal activated carbon, silica gel, sulfur adsorbent, carbonized sludge, and molecular sieve 13X. Coconut activated carbon showed the highest removal efficiency of more than 95%. The desorption of hexamethyldisiloxane (L2) from the adsorbent, however, resulted in the remarkable concentration variation of the compound in the treated gas. Silica gel, which had high adsorption capacity for L2 in single substance adsorption experiment in the other study, could not remove the component in the actual landfill gas while it adsorbed well octamethylcyclotetrasiloxane (D4) and decamethylcyclopentasiloxane (D5) in the LFG. Therefore the elimination of hexamethyldisiloxane is an important factor to determine the level of total organosilicon compound in pretreated landfill gas. Moreover, the L2 from the actual landfill gas was effectively adsorbed by the serial adsorption test using two columns packed with coconut activated carbon which has the great capacity of siloxanes removal among others. In order to utilize efficiently LFG as a renewable energy, the emission and adsorptive characteristics of the substance to be treated should be considered for the organization, operation, and management of pretreatment process.

• Asian Journal of Atmospheric Environment
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• v.12 no.3
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• pp.255-273
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• 2018

To develop effective emission abatement strategies for eighteen coal-fired power plants located throughout Korea, power plant emission data and TAPM (The Air Pollution Model) were used to quantify the impact of emission reductions on primary $PM_{10}$ concentrations. TAPM was validated for two separate time periods: a high $PM_{10}$ concentration period from April 7 to 12, 2016, and a low $PM_{10}$ concentration period from June 1 to June 6 2016. The validated model was then used to analyze the impacts of five applicable power plant shut-down scenarios. The results showed that shut-down of four power plants located within the Seoul metropolitan area (SMA) would result in up to 18.9% reduction in maximum $PM_{10}$ concentrations, depending on synoptic conditions. A scenario for the shutdown of a single low stack height with highest-emission power plant located nearest to Seoul showed a small impact on averaged $PM_{10}$ concentrations (~1%) and 4.4% ($0.54{\mu}g/m^3$) decrease in maximum concentration. The scenario for four shutdowns for power plants aged more than 30 years within SMA also showed a highest improvement of 6.4% ($0.26{\mu}g/m^3$ in April) in averaged $PM_{10}$ concentrations, and of 18.9% ($2.33{\mu}g/m^3$ in June) in maximum concentration, showing almost linear relationship in and around SMA. Reducing gaseous air pollutant emissions was also found to be significant in controlling high $PM_{10}$ concentrations, indicating the effectiveness of coreduction of power plant emissions together with diesel vehicle emissions in the SMA. In addition, this study is implying that secondary production process generating $PM_{10}$ pollution may be a significant process throughout most regions in Korea, and therefore concurrent abatement of both gas and particle emissions will result in more pronounced improvements in air quality over the urban cities in South Korea.

• International Journal of Internet, Broadcasting and Communication
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• v.14 no.3
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• pp.115-130
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• 2022

Barrage is an interactive method based on video, and the video itself is visualized from the viewer's point of view to play people's emotions, and it already has an advantage in communication by attracting people's attention using stories and plays. Advances in digital and mobile technology have enabled video viewing anytime, anywhere. Due to the nature of the barrage site that relies on the same video content or playback to participate in video sharing through computers or mobile clients, a barrage that can express users' feelings and thoughts will be added, breaking down the limit of content acceptance by a single user. Barrage satisfy users' entertainment needs, and their influence is growing. Gradually, they are heading to offline movie theaters and TV from barrage videos on the Internet. Attempts to function as offline ammunition facilitated technological innovation for media convergence by converging mobile media with PCs and screens. At the same time, the trend of media convergence shown by coal screens is also a trend of overall technological development. A barrage is an extension of human communication skills. The properties of the barrage fit well with the need for experiential marketing (via video). It can provide a visual experience and create an atmosphere of "surrounding and watching" and eliminate loneliness. Barrage itself provides a function to comment on videos, which is a trigger point for the reason, and donation adds to the amount of information in the video, adding to the fun of the video. Through the barrage, sarcastic, teasing, and expressing emotions can bring entertainment experiences, and users can produce and communicate their shooting text while consuming the satisfaction brought by the shooting. At the same time, Barrage attaches great importance to the needs of the masses, is more individual and diversified, and has commercial significance in line with the current development trend of the Internet. As a new interactive method, barrage contains huge potential value. However, the impact of the interactive way of barrage should also be viewed from a dialectical point of view, how to solve the difficulties in the development of barrage. The way to solve the difficulties in the development of barrage is worth studying. This research will analyze the reasons for the development of barrage and the analysis of Chinese barrage websites, the case analysis of barrage videos, the exploration of the characteristics and values of barrage, and the problems in the process of barrage communication. Provide reference for the development of industrial culture.

• Particle and aerosol research
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• v.19 no.3
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• pp.53-62
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• 2023

This study compared the collection efficiency of a two-stage electrostatic precipitator (ESP) with a lightweight PET film-coated carbon electrode collector plate, depending on the relative humidity of the exhaust gas and the applied voltage to the pre-charger. It was confirmed that the onset voltage at which corona discharge occurs decreases and the discharge current decreases at the same voltage as the relative humidity increases. On the other hand, even though there was almost no change in the diameter of the particles generated depending on the relative humidity, the efficiency was higher at the same voltage as the relative humidity increased. In addition, by applying a two-stage ESP structure, the collection efficiency was higher than that of a single-stage electrostatic precipitator under the same conditions. The ESP using the carbon electrode coated with PET film used in this study is expected to be effective in various aspects such as weight and in the current situation where environmental regulations are rapidly tightening.