• New & Renewable Energy
• /
• v.6 no.2
• /
• pp.27-32
• /
• 2010

Low Calorific Gas Turbine (LCGT) has been developed as a next generation power system using landfill gas (LFG) and biogas made from various organic wastes, food Waste, waste water and Livestock biogas. Low calorific fuel purification by pretreatment system and carbon dioxide fixation by green house system are very important design target for the optimum applications of LCGT. Main troubles of Low Calorific Gas Turbine system was derived from the impurities such as hydro sulfide, siloxane, water contained in biogas. Even if the quality of the bio fuel is not better than natural gas, LCGT may take low quality gas fuel and environmental friendly power system. The mechanical characterisitics of LCGT system is a high energy efficiency (>70%), wide range of output power (30 kW - 30 MW class) and very clean emission from power system (low NOx). A green house has been designed for four different carbon dioxide concentration from ambient air to 2000 ppm by utilizing the exhaust gas and hot water from LCGT system. LCGT is expected to contribute achieving the target of Renewable Portfolio Standards (RPS).

• Journal of the Korea Institute of Military Science and Technology
• /
• v.16 no.5
• /
• pp.690-702
• /
• 2013

Ionic liquids(ILs) have been the most investigated chemicals among green solvents including water, glycerol, supercritical carbon dioxdie($scCO_2$). ILs are attracting organic as well as inorganic chemicals because most ionic liquids' vapor pressures are very low so that ILs are liquids phase at ambient conditions. ILs are composed of various anions and cations, thus chemists can design functionalized solvents and/or catalysts that can be used in specific synthetic reactions by means of combinations of different ions. Many scientists believe ILs being green materials because of its low vapor pressure as well as the flexibility in controlling the chemical and physical properties. In this review the author describes recent development of ILs focused on imidazolium and pyridinium ILs which are being most investigated presently. In order to apply this materials in industrial level, the toxicity matter must be resolved first. In this regard, the author describes recent research trend regarding environmental effects by ILs as well as some meaningful results as well.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.24 no.3
• /
• pp.319-329
• /
• 2016

Globally, many researchers have been trying to improve the fuel economy of a vehicle for satisfying future $CO_2$ regulation and minimizing air pollution problem. For the same background, diesel engine and vehicle system optimization using simulation models have been key technologies for the improvement of vehicle system efficiency. Therefore, in this study, calibration method for the air breathing system of a WGT diesel engine using mean value model has been composed for efficient engine and vehicle optimization simulation researches. And virtual WGT performances have been calculated for a 2 cylinder downsized diesel engine system. From these researches, the calibration method for the boost pressure and EGR rate of a virtual diesel engine related with WGT performances could be composed and some of technical issue related with downsized diesel engine could be investigated.

• Asian Journal of Atmospheric Environment
• /
• v.11 no.3
• /
• pp.194-201
• /
• 2017

This study investigates the factors that affect China's air pollution using city-level panel data and spatial econometric models. We address three air pollutants ($PM_{10}$, $SO_2$, and $NO_2$) present in 30 cities in China between 2004-2012 using global OLS and spatial models. To develop the spatial econometric analysis, we create a spatial weights matrix to define spatial patterns based on two neighborhood criteria - the queen contiguity and k nearest neighbors. The results show that the estimated coefficients are relatively consistent across different spatial weight criteria. The OLS models indicate that the effect of green spaces is statistically significant in decreasing the concentrations of all air pollutants. In the $PM_{10}$ and $SO_2$ analyses, the OLS models find that the number of buses and population density are also positively related to a reduction in the concentration of air pollutants. In addition, an increase in the temperature and the presence of secondary industries increase $SO_2$ and $NO_2$ concentrations, respectively. All spatial models capture a positive and significant effect of green spaces on reducing the concentration of each air pollutant. Our results suggest that green spaces in cities should receive priority consideration in local planning aimed at sustainable development. Furthermore, policymakers need to be able to discern the differences among pollutants when establishing environmental policies.

• Journal of Microbiology and Biotechnology
• /
• v.12 no.6
• /
• pp.882-889
• /
• 2002

Hantaan vims production, using human immortalized retina cell (PER. C6), was investigated to develop an inactivated virus vaccine. To infect Hantaan virus into PER. C6, two infection methods (medium-to-cell and cell-to-cell) were tried, and IFA results showed that the cell-to-cell infection method was very useful for producing Hantaan virus-infected PER, C6. Hantaan virus production was significantly affected by the growth rate of PER. C6 and the content of FBS in medium. Higher specific growth rate of infected PER. C6 and lower FBS content induced higher production of Hantaan virus. The inactivated human cell-culture vaccines with various EIA titers were prepared, their antibody responses were compared with those of inactivated suckling mouse brain vaccines ($Hantavax^처리불가$). and the result showed their immunogenicities were slightly higher than those of inactivated suckling mouse vaccines. Therefore, this study shows the possibility of the development of Hantaan virus vaccine from a human cell culture.

• Journal of Electrochemical Science and Technology
• /
• v.2 no.2
• /
• pp.116-123
• /
• 2011

Herein, a novel preparation method of highly homogeneous carbon-silicon composite materials was presented. In contrast to conventional solvent evaporation method, a milled silicon-graphite or its oxidized material were directly reacted with petroleum-derived pitch precursor. After thermal reaction under high pressure, pitch-graphite-silicon composite was prepared. Carbon-graphite-silicon composite were prepared by an air-oxidization and following carbonization. From energy dispersive spectroscopy, it was observed that small Si particles were highly embedded within carbon, which was confirmed by disappearance of Si peaks in Raman spectra. Furthermore, X-ray diffraction and Raman spectra revealed that carbon crystallinity decreased when the strongly oxidized silicon-graphite was added, which was probably due to oxygen-induced cross-linking. From the anode application in lithium ion batteries, carbon-graphite-silicon composite anode displayed a high capacity ($565\;mAh\;g^{-1}$), a good initial efficiency (68%) and an good cyclability (88% retention at 50 cycles), which were attributed to the high dispersion of Si particles within cabon. In case of the strongly oxidized silicongraphite addtion, a decrease of reversible capacity was observed due to its low crystallinity.

• Proceedings of the Korean Society for Quality Management Conference
• /
• 2010.04a
• /
• pp.465-470
• /
• 2010

Korea government declared that "low carbon, green growth" through green technologies and clean energy to be the new national vision for the next 60 years(President's Liberation Day speech on Aug. 15, 2008). And succeeding "Green New Deal" plan involves nine core projects including energy saving, recycling, clean energy development. It is because hydrogen fuel cell vehicles, using electricity from chemical reaction of hydrogen and oxygen, let out water which is a by-product of such chemical reaction instead of emitting harmful particulate and gases such as NOX, SOX and CO2 that hydrogen fuel cell vehicles and its technology are drawing public attention as one of the sensible solutions in accomplishing "low carbon, green growth" agenda. Nevertheless There are many chances that let the people have a practical experience of hydrogen fuel cell vehicles. Sometimes new products, including hydrogen fuel cell vehicles, made by advanced technology can not penetrate through the market when it faces public skepticism that is stimulated from lack of knowledge and experience. That is the reason why not only cost benefit analyses and scientific risk assessments but also public acceptance studies toward hydrogen fuel cell vehicles have to be performed [Schulte, 2004]. This research address a need for comprehensive study on factors influencing public acceptance of hydrogen fuel cell car, specifically focusing on impacts of personal experience related to governmental science and technology policy toward public acceptance.

• Journal of Forest and Environmental Science
• /
• v.34 no.3
• /
• pp.246-248
• /
• 2018

Urban development and population have augmented the increase of impervious land-cover. This phenomenon has amplified the effects of climate change and increasing urban island effects due to increases in urban temperatures. Seoul, South Korea is one of the largest metropolitan cities in the world. While land uses in Seoul vary, land cover patterns have not changed much (under 2%) in the past 10 years, making the city a prime target for studying the effects of land cover types on the urban temperature. This research seeks to generalize the urban temperature of Seoul through a series of statistical tests using multi-temporal remote sensing data focusing on multiple scales and typologies of green space to determine its overall effectiveness in reducing the urban heat. The distribution of LST values was reduced as the size of urban forests increased. It means that changing temperature of large-scale green-spaces is less influenced because the broad distribution could be resulted in various external variables such as slope aspect, topographic height and density of planting areas, while small-scale urban forests are more affected from that. The large-scale green spaces contributed significantly to lowering urban temperature by showing a similar mean LST value. Both of concentration and dispersal of urban forests affected the reduction of urban temperature. Therefore, the findings of this research support that creating urban forests in an urban region could reduce urban temperature regardless of the scale.

• Journal of Environmental Impact Assessment
• /
• v.8 no.3
• /
• pp.77-90
• /
• 1999

The degree of green naturality (DGN) has played a key role for maintaining the environmental quality from inappropriate developments, although the quality and effectiveness of the mapping of DGN has been under debate. In this study, spatial distribution of degree of green naturality was initially estimated from forest stand maps that were produced from the aerial photo interpretation and extensive field survey. Once the boundary of initial classes of DGN were defined, it were overlaid with normalized difference vegetation index (NDVI) data that were derived from the recently obtained Landsat Thematic Mapper data. NDVI was calculated for each pixel from the radiometrically corrected satellite image. There were no significant differences in mean values of vegetation index among the initial DGN classes. However, the satellite derived vegetation index was very effective to delineate the developed and damaged forest lands and to adjust the initial value of DGN according to the distribution of NDVI within each class.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.21 no.3
• /
• pp.255-263
• /
• 2018

This paper investigated design requirements for piston pumps, which were used as the power source of light rescue vehicle, and designed a piston pump satisfying such requirements. In order to satisfy the driving specification of the rescue device, the pump needs to be designed using the displacement volume of 110 cc/rev, the pressure of 350 bar and the rotation speed of 2,200 rev/min. The design was verified by flow and structural analyses respectively. The shape of the piston pump was optimized in terms of both flow characteristics and structural stability. A test equipment was also fabricated to verify the developed piston pump and test conditions were established. Finally, the developed piston pump was tested for its performance and operating temperature.