• Transactions of the Korean Society of Automotive Engineers
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• v.17 no.5
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• pp.39-45
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• 2009

An experimental research with 2.0 liter 4-cylinder turbocharged diesel engine was carried out to investigate the combustion and emission characteristics for various alternative fuels. The conventional diesel fuel, neat GTL, blends of 80% of GTL and 20% of biodiesel derived from waste cooking oil are utilized without any modification of engine hardware and ECU data. For GTL and blends of GTL/biodiesel fuel, the ignition delay decreased at the same operating conditions, and overall combustion duration increased slightly. Also, the peak cylinder pressure increased for blends of GTL/biodiesel compared to diesel and GTL fuel. THC and CO emissions with blends of GTL/biodiesel compared to other fuels decreased for the low and middle load conditions. But NOx emission increased due to oxygen content in biodiesel. The number concentrations of PM are higher for blends of GTL/biodiesel than other test fuels in the nucleation mode, while it had an opposite tendency in the accumulation mode, which implies more reduction of PM for blends of GTL/biodiesel on the base of mass concentration.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.30 no.7
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• pp.441-446
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• 2017

Aluminum nitride fibers were synthesized by carbothermal reduction and nitridation of precursor fibers obtained by electrospinning. The starting materials used to synthesize the AlN fibers were $Al(NO_3)_3{\cdot}9H_2O$ and urea. Polyvinylpyrrolidone with increasing viscidity was used as the carbon source to obtain a composite solution. The mixed solution was drawn into a plastic syringe with a stainless steel needle, which was used as the spinneret and connected to a 20 kV power supply. A high voltage was supplied to the solution to facilitate the formation of a dense net of fibers on the collector. The precursor fibers were dried at $100^{\circ}C$ and then heated to $1,400^{\circ}C$ for 1 h in a microwave furnace under $N_2$ gas flow for the carbothermal reduction and nitridation. X-ray diffraction studies indicated that the synthesized fibers consisted of the AlN phase. Field emission scanning electron microscopy studies indicated that the diameter of the calcined fibers was approximately 100 nm.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.50 no.1
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• pp.58-66
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• 2014

The purpose of the study is to estimate the Green-House-Gas (GHG) emissions from domestic eel farm in the water recirculation system or still-water system by the assessment of energy consumptions and GHG emissions for establishing to reduce standards of GHG from a sustainable perspective. GHG emission components as seeds, feed, fuel, electricity, fixed capital, fish respiration, and others were analysed at the different culture type between water recirculation system and still-water system by 3 stage farm size of small, medium, large scale. The result showed that the mean GHG emission of the eel farm was $18.7kg{\cdot}CO_2$ in the stage of production per fish 1kg at different culture type and farm size. Therefore it could be useful for policy, planning, and regulation of aquaculture development with establishing GHG reduction standards.

• Korean Journal of Organic Agriculture
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• v.20 no.2
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• pp.161-172
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• 2012

This study was carried out to estimate carbon footprint and to establish of LCA of garlic production system. We have case study in cultivate garlic 1 kg calculate in carbon footprint. LCA carried out to estimate carbon footprint and to establish of LCI (life cycle inventory) database of garlic production system. The data is from Research of Farmer's income in 2010 (RDA, 2011), and used Pass (5.0.0) program. The value of fertilizer, amount of pesticide input were shown the environmental effect and direct emission. Carbon footprint in agriculture guarantees the choice right the consumer to choose the lower carbon goods. Its can make to strengthen of agriculture and food industry's reduction effort of $CO_2$. Nowadays consumer requests food's safety and environment friendly process. Carbon footprint also needs consumer's relief and incentives.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.173-176
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• 2009

We suggest a new protective layer for PDP consists of SrO and MgO double layer. This double layer structure protects SrO layer from the contamination by $H_2O$ or $CO_2$ in the air and enable SrO to play as the main cathode material. It was confirmed that the high secondary electron emission characteristics of SrO by Xe ion can bring considerable driving voltage reduction and improvement of luminance and luminous efficacy in PDP.

• Journal of Photoscience
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• v.11 no.3
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• pp.95-99
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• 2004

Optical absorption and emission studies have been carried out to understand the effect of deuterium on the solvent dependent photophysical properties of curcumin in deuterated solvents such as $CDCl_3,\;(CD_3)_2SO,\;(CD_3)_2CO,\;CD_3OD\;and\;CD_3CN$. Optical absorption spectral studies showed that there is no significant shift in absorption maxima compared to the non-deuterated solvent. The fluorescence maxima shows significant shift with polarity of solvent but not much affected by the deuteration. The fluorescence quantum yield of curcumin increased marginally in almost all the deuterated solvents, indicating reduction in the non-radiative pathways. The fluorescence decay was biexponential in all the solvents and the average fluorescence lifetime was not much affected with deuteration, but showed decrease with increasing solvent polarity. Based on these studies, it is concluded that intermolecular hydrogen transfer is only partially responsible for the excited state deactivation of curcumin.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.739-744
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• 2010

As recent traffic policy focuses on reduction of congestion and environmental contamination, with a catch phrase, 'Green Traffic', Low Carbon Green Growth' and 'Sustainable Development', introducing the new eco-friendly transport means including railway has been emerging as critical issue. Included in the new transport means are BRT, Bimodal Tram and LRT, and this study was intended to evaluate and analyze Bimodal, among others, which generates less emission, noise and vibration thanks to hybrid type traction system employed by Bimodal Tram, which is considered a future-oriented system because of eco-friendly features and cost efficiency as well as punctuality and convenient accessibility to bus. Thus in this study, appropriateness of Bimodal Tram comparing to other system(BRT) was suggested, using conversion traffic from the road, traffic speed and CO2 emission at the metropolitan area and large provincial areas as the barometer in evaluation, and furthermore, the measures applicable to introduction strategy that will meet various functional aspects in urban area in the coming days were developed.

• Journal of Environmental Science International
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• v.20 no.2
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• pp.251-260
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• 2011

$TiO_2$- and $SiO_2$-supported $Co_3O_4$, Pt and $Co_3O_4$-Pt catalysts have been studied for CO and $C_3H_8$ oxidations at temperatures less than $250^{\circ}C$ which is a lower limit of light-off temperatures to oxidize them during emission test cycles of gasoline-fueled automotives with TWCs (three-way catalytic converters) consisting mainly of Pt, Pd and Rh. All the catalysts after appropriate activation such as calcination at $350^{\circ}C$ and reduction at $400^{\circ}C$ exhibited significant dependence on both their preparation techniques and supports upon CO oxidation at chosen temperatures. A Pt/$TiO_2$ catalyst prepared by using an ion-exchange method (IE) has much better activity for such CO oxidation because of smaller Pt nanoparticles, compared to a supported Pt obtained via an incipient wetness (IW). Supported $Co_3O_4$-only catalysts are very active for CO oxidation even at $100^{\circ}C$, but the use of $TiO_2$ as a support and the IW technique give the best performances. These effects on supports and preparation methods were indicated for $Co_3O_4$-Pt catalysts. Based on activity profiles of CO oxidation at $100^{\circ}C$ over a physical mixture of supported Pt and $Co_3O_4$ after activation under different conditions, and typical light-off temperatures of CO and unburned hydrocarbons in common TWCs as tested for $C_3H_8$ oxidation at $250^{\circ}C$ with a Pt-exchanged $SiO_2$ catalyst, this study may offer an useful approach to substitute $Co_3O_4$ for a part of platinum group metals, particularly Pt, thereby lowering the usage of the precious metals.

• Journal of the Society of Naval Architects of Korea
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• v.54 no.4
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• pp.352-359
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• 2017

Because the Energy Efficiency Design Index(EEDI) came into effect in 2013, it is necessary to develop a new technology to overcome $CO_2$ emission regulations. In structural design viewpoint, lots of researches are carried out to develop eco-friendly and high fuel efficiency ships by weight reduction. By using the automated compartment arrangement system and automated structural design algorithm which were developed by the authors, new researches are performing to combine the above two systems. However, the effect of weight reduction was not significant because structural designs by using these systems for the midship part was carried out only focused on the minimum still water bending moment. In this paper, at first, good compartment arrangements which give the minimum still water bending moment and(or) shear force were chosen by using the automated compartment system. And then, influence of shear force on weight reduction was investigated by using the automated structural design algorithm considering longitudinal strength, local strength and shear strength of longitudinal members in cargo holds. Conclusively, it is necessary to consider the minimum still water bending moment and shear force simultaneously to reduce the weight of mid-sized bulk carrier. Also, good compartment arrangement which gives much more weight reduction compared with existing ship was proposed.

• Journal of Climate Change Research
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• v.7 no.3
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• pp.217-229
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• 2016

Increased evidences reveal that the global climate change adversely affect on the environment. Smart grid system is one of the ways to reduce greenhouse gas emissions in the electricity generation sector. Since 2013, Korea Electric Power Corporation (KEPCO) has installed smart grid station in KEPCO office buildings. The goal of this paper is two folds. One is to quantify the reduction in greenhouse gas emissions through smart grid stations installed in KEPCO office buildings as a part of pilot project. Among components of smart grid stations, this research focused on the photovoltaic power system (PV) and energy storage system (ESS). The other is to estimate the reduction in greenhouse gas emissions when PV is applied on individual houses. Results show that greenhouse gas emissions reduce 5.8~11.3% of the emissions generated through the electricity usage after PV is applied in KEPCO office buildings. The greenhouse gas emissions reduction from ESS is not apparent. When PV of 200~500 W is installed in individual houses, annual greenhouse gas emission reduction in 2016 is expected to be approximately $2.2{\sim}5.4million\;tCO_2-eq$, equivalent to 6~15% of greenhouse gas emissions through the electricity usage in the house hold sector. The saving of annual electricity cost in the individual house through PV of 200 W and 500 W is expected to be 47~179 thous and KRW and 123~451 thousand KRW, respectively. Results analyzed in this study show the environmental effect of the smart grid station. In addition, the results can be further used as guidance in implementing similar projects.