• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.8
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• pp.677-685
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• 2014

A direct carbon fuel cell (DCFC) generates electricity directly by converting the chemical energy in coal. In particular, a DCFC system with a solid oxide electrolyte and molten carbonate anode media has been proposed by SRI. In this system, however, there are conflicting effects of temperature, which enhances the ion conductivity of the solid electrolyte and reactivity at the electrodes while causing a stability problem for the anode media. In this study, the effect of temperature on the stability of a carbon-carbonate mixture was investigated experimentally. TGA analysis was conducted under either nitrogen or carbon dioxide ambient for $Li_2CO_3$, $K_2CO_3$, and their mixtures with carbon black. The composition of the exit gas was also monitored during temperature elevation. A simplified reaction model was suggested by considering the decomposition of carbonates and the catalyzed Boudouard reactions. The suggested model could well explain both the measured weight loss of the mixture and the gas formation from it.

• Journal of the Korean Society for Railway
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• v.17 no.1
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• pp.1-6
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• 2014

Recent international environmental regulations are focused on reducing pre-contamination and on sustainable development prior to the usage stage of a product. The Environmental Performance Declaration is being used as a tool for quantifying the environmental performance of products, to reduce contamination in advance, and for advertising the results of railway vehicles in Europe. In this study, a life cycle assessment of the tilting train was conducted, the first such case study in Korea, according to the ISO 14025 standard and Korea EDP (Environmental Declaration of the Product) rule. As a result of the LCA, the life cycle carbon emission of the tilting train was determined to be $3.54{\times}10^7kgCO_2eq.$ which is higher than that of a European train. Also, the amount of $CO_2$ emission of the Mcp and car body is higher than that of the other car and bogie.

• KIPS Transactions on Computer and Communication Systems
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• v.2 no.1
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• pp.35-42
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• 2013

This paper shows the positivistic approach for analyzing the effect of ICT on the reduction of greenhouse gas (GHG) emission. The real-time navigation was selected for the ICT based service in this research, and the CO2 reduction ratios of the optimized routes in the navigation were compared with the reduction ratios of the shortest routes in existing navigations. The results of experiments showed the driving based on the optimized routes has more reduction effects than the driving on the basis of the shortest routes. Also, new evaluation method for GHG emission was suggested by the quantification and monitoring approaches on the basis of the Clean Development Mechanism (CDM) in this paper. The results of this paper can be used as a preliminary research for the effect of ICT on the reduction of GHG emission. The evaluation method which suggested in this paper will be suggested to CDM as the new standard for the reduction of GHG emission in the transportation field as well.

• Journal of Energy Engineering
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• v.24 no.4
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• pp.200-210
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• 2015

The modeling for fast pyrolysis of biomass in fluidized bed reactor has been developed for accurate prediction of bio-oil and gas products and for yield improvement. The purpose of this study is to analyze and to compare the CFD(Computational Fluid Dynamics) simulation results with the experimental data from the CFD simulation results with the experimental data from the reference(Mellin et al., 2014) for gas products generated during fast pyrolysis of biomass in fluidized bed reactor. CFD(ANSYS FLUENT v.15.0) was used for the simulation. Complex pyrolysis reaction scheme of biomass subcomponents was applied for the simulation of pyrolysis reaction. This pyrolysis reaction scheme was included reaction of cellulose, hemicellulose, lignin in detail, gas products obtained from pyrolysis were mainly $CO_2$, CO, $CH_4$, $H_2$, $C_2H_4$. The deviation between the simulation results from this study and experimental data from the reference was calculated about 3.7%p, 4.6%p, 3.9%p for $CH_4$, $H_2$, $C_2H_4$ respectively, whereas 9.6%p and 6.7%p for $CO_2$ and CO which are relatively high. Through this study, it is possible to predict gas products accurately by using CFD simulation approach. Moreover, this modeling approach should be developed to predict fluidized bed reactor performance and other gas product yields.

• Journal of Advanced Marine Engineering and Technology
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• v.28 no.3
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• pp.516-521
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• 2004

In this paper, the effects of ethanol blended gasoline on emissions and their catalytic conversion efficiencies characteristics were investigated in gasoline engine with an electronic fuel injection. The results showed that the increase of ethanol concentration in the blended fuels brought the reduction of THC and $CO_2$ emissions from the gasoline engine. THC emissions were drastically reduced up to thirty percent. And brake specific fuel consumption was increased. but brake specific energy consumption was similar level. However. unburned ethanol and acetaldehyde emissions increased. The conversion efficiency of Pt/Rh based three-way catalysts and the effect of ethanol on CO and NOx emissions were investigated by the change of engine speed. load and air/fuel ratio. Furthermore, the ethanol blended fuel results in the reduction effect of THC. CO and NOx emissions at idle speed.

• KSBB Journal
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• v.20 no.6
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• pp.458-463
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• 2005

[ $H_2$ ] from CO and water was continuously produced in a trickle bed reactor(TBR) using Citrobacter amalonaticus Y19. When the strain C. was cultivated in a stirred-tank reactor under a chemoheterotrophic and aerobic condition, the high final cell concentration of 13 g/L was obtained at 10 hr. When the culture was switched to an anaerobic condition with the continuous supply of gaseous CO, CO-dependent hydrogenase was fully induced and its hydrogen production activity approached 16 mmol/g cell/hr in 60 hr. The fully induced C. amalonaticus Y19 cells were circulated through a TBR packed with polyurethane foam, and the TBR was operated for more than 20 days for $H_2$ production. As gas retention time decreased or inlet CO partial pressure increased, $H_2$ production rate increased but the conversion from CO to $H_2$ decreased. The maximum $H_2$ production rate obtained was 16 mmol/L/hr at the gas retention time of 25 min and the CO inlet partial pressure of 0.4 atm. The high $H_2$ production rate was attributed to the high cell density in the liquid phase circulating the TBR as well as the high surface area of polyurethane foam used as packing material of the TBR.

• Fire Science and Engineering
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• v.17 no.2
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• pp.35-42
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• 2003

In this study, we tried to evaluate the ignitibility, flammability, heat release rate, and toxicity of five different types of burning artificial leather sofa covers that are widely used in entertainment service industry buildings. As the results of this study, putting the artificial leathers under fire conditions we found out following results auto-ignition temperature was$ 427~437^{\circ}C$, limiting oxygen index was 19~20%; at heat flux of $25 kW\m^2$, ignition time was 10~16s and peak heat release rate was $147~277 kW\m^2$; and at heat flux of$ 35 kW\m^2$, ignition time was 6~9s and peak heat release rate was $176~296 kW\m^2$. The toxic materials discharged from the burning leathers were 5,550~6,290 ppm of CO, 18,500~23,400 ppm of $CO_2$, 110~140 ppm, of HCl, 13~65 ppm of HCN and 145~220 ppm of NOx.

• Journal of Hydrogen and New Energy
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• v.26 no.5
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• pp.402-408
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• 2015

In D-T fusion reaction, $D_2$ (duterium) and $T_2$(tritium) are used as fuel gas. The exhaust gas of nuclear fusion includes hydrogen isotopes $Q_2$ (Q means H, D or T), tritiated components ($CQ_4$ and $Q_2O$), CO, $CO_2$, etc. All of hydrogen isotopes should be recovered before released to the atmosphere. This study focused on the recovery of hydrogen isotopes from $CQ_4$ and $Q_2O$. Two kinds of experiments were conducted to investigate the catalytic reaction characteristics of SMR (Steam Methane Reforming) and WGS (Water Gas Shift) reactions using Pt catalyst. First test was performed to convert $CH_4$ into $H_2$ using 6% $CH_4$, 6% CO/Ar feed gas. In the other test, 100% CO gas was used to convert $H_2O$ into $H_2$ at various reaction conditions (reaction temperature, S/C ratio, GHSV). As a result of the first test, $CH_4$ and CO conversion were 41.6%, 57.8% respectively at $600^{\circ}C$, S/C ratio 3, GHSV $2000hr^{-1}$. And CO conversion was 72% at $400^{\circ}C$, S/C ratio 0.95, GHSV $333hr^{-1}$ in the second test.

• Journal of the Korea Organic Resources Recycling Association
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• v.10 no.4
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• pp.65-74
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• 2002

This Study was investigated operating condition of pyrolysis processing for sludge disposal in sewage treatment plant. Important parameters studied include running time of pyrolysis, run time of dry and pyrolysis processing, water content of sewage sludge, solids amount of sewage sludge(TS%), condition of pyrolysis temperature. Most degradation reaction of sewage sludge are first order, it assumed first order and elucidated the kinetics. This was the basis of characteristics analysis of sludge degradation mechanism. Also, with the increasing of temperature, how the yield of oil and char product change was observed, and the distribution of gas product components was observed. Main components of gas and carbon product are a little difference with pyrolysis temperature, but it consist of $CH_4$, $C_2H_4$, $C_3H_8$, $C_4H_{10}$, toluene, $C_6H_6$, $SO_2$, CO etc. The gas of $C_1-C_4$ yield increased along with degradation temperature of $670^{\circ}C$ and oil yield decreased of $C_6H_6$ and $C_6H_5OH$ with temperature of $600^{\circ}C$. Particularly, low value added char yield 134kg/t at $670^{\circ}C$, but increased to 194kg/t at pyrolysis temperature of $600^{\circ}C$. In the result of elementary analysis on it, it is mainly composed of carbon. From this fact, in pyrolysis of sludge, it comfirmed that carbonization reaction occur at high temperature well.

• Proceedings of the KIEE Conference
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• 2008.04a
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• pp.45-46
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• 2008

There are various polluting emissions related to the air quality such as $NO_x$, $CO_2$, CO, VOCs, $O_3$, $SO_2$, $CH_4$, $H_2S$, $NH_3$, etc. We need the system that reduces emission of these environment gases and detects risk factors in modern society. Therefore, if we use the USN(Ubiquitous Sensor Network) technology and a MAV(Micro Air Vehicle) Quad Rotor which can be hovering and moving free for setting up the environment gas sensing system, the realtime measurement on environment gases is facilitated and by extension, in application of traffic watchdog, forest fire surveillance and counter-terrorism efforts, we anticipate making better use of a Quad Rotor.