• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.57 no.3
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• pp.256-263
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• 2021

In this study, blending oils of diesel oil and butanol were used as fuel oil for diesel engine to measure combustion pressure, fuel consumption, air ratio and exhaust gas emission due to various operating conditions such as engine revolution and torque. Using these data, the results of analyzing the engine performance, combustion characteristics and exhaust emission characteristics such as NOx (nitrogen oxides), CO₂ (carbon dioxide), CO (carbon monoxide) and soot were as follows. The fuel conversion efficiency at each load was highest when driven in the engine revolution determined by a fixed pitch propeller law. Except 30% butanol blending oil, fuel conversion efficiency of the other fuel oils increased as the load increased. Compared to diesel oil, using 10% and 20% butanol blending oil as fuel oil was advantageous in terms of thermal efficiency, but it did not have a significant impact on the reduction of exhaust gas emissions. On the other hand, future research is needed on the results of the 20% butanol blending oil showing lower or similar levels of smoke concentration and carbon monoxide emission rate other than those types of diesel oil.

• KEPCO Journal on Electric Power and Energy
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• v.2 no.4
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• pp.517-523
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• 2016

South Korea is the 8th biggest greenhouse gas emitter in the world due to its phenomenal economic growth based on manufacturing, and it is ranked first among OECD members for the rate of increase in emissions. Thus, the Korea government has voluntarily presented a reduction target and demonstrated global leadership. For the reduction of nation's GHG emission, importance of CCU(Carbon Capture and Utilization) along with CCS(Carbon Capture and Storage) technology development is increased. CCU technology is $CO_2$ utilization technology for the usage of $CO_2$ from flue gas and it can create a new economic value while reducing $CO_2$ emission. Therefore, with continued technology development, the number of application of CCU technology is increasing globally.

• Applied Chemistry for Engineering
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• v.28 no.1
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• pp.112-117
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• 2017

This study demonstrated the emission of combustion gases of medium density fibreboard (MDF)s coated with piperazinomethyl-bis-phosphonic acid (PIPEABP), methylpiperazinomethyl-bis-phosphonic acid (MPIPEABP), N,N-dimethylethylenediaminomethyl-bis-phosphonic acid (MDEDAP), or bis-(dimethylaminomethyl) phosphinic acid (DMDAP). Each MDFs were coated in three times with a brush with 15 wt% aqueous solution of the phosphorus-nitrogen acid additives. After the specimens were dried at room temperature, the emission of combustion gases was tested using a cone calorimeter (ISO 5660-1, 2). The peak smoke production rate ($SPR_{peak}$) of the specimens coated with phosphorus-nitrogen acids was 18.5 to 41.5%, which is lower than that of using the virgin plate. However, the production of peak carbon monoxide ($CO_{peak}$) was 6.7 to 24.2% higher than that of using the virgin plate. Also, the peak carbon dioxide ($CO_{2peak}$) was 4.2 to 24.4% lower than that of using virgin plate. While the peak oxygen depletion rate was much higher than the level of 15%, which can be fatal to humans and the resulting risk could thus be eliminated. Overall, the combustibility of coated specimens was partially suppressed, but showed a negative effect on the reduction of carbon monoxide.

• Journal of ILASS-Korea
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• v.12 no.3
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• pp.166-171
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• 2007

Recently, many studies on HSDI diesel engines have been performed to reduce the fuel consumption and $CO_2$ emission. One of the prominent technique to reduce emission is a high pressure multiple injection. For this technique, the injection rate is a critical parameter in order to determine precise injection duration and timing for combustion control. Thus the purpose of this study was to investigate relationship between the injection rate and the time-signature of chamber pressure at different injection pressure conditions in a common rail direct injection type injector using the Zeuch method. Using the measured correlation constants, estimated fuel injection rates are presented at many different injection conditions.

• Horticultural Science & Technology
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• v.30 no.5
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• pp.501-508
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• 2012

Reducing carbon dioxide ($CO_2$) exhaust has become a major issue for society in the last few years, especially since the initial release of the Kyoto Protocol in 1997 that strictly limited the emissions of greenhouse gas for each country. One of the primary sectors affecting the levels of atmospheric greenhouse gases is agriculture where $CO_2$ is not only consumed by plants but also produced from various types of soil and agricultural ecosystems including greenhouses. In greenhouse cultivation, $CO_2$ concentration plays an essential role in the photosynthesis process of crops. Optimum control of greenhouse $CO_2$ enrichment based on accurate monitoring of the added $CO_2$ can improve profitability through efficient crop production and reduce environmental impact, compared to traditional management practices. In this study, a sensor-based control system that could estimate the required $CO_2$ concentration considering emission from soil for cucumber greenhouses was developed and evaluated. The relative profitability index (RPI) was defined by the ratio of growth rate to supplied $CO_2$. RPI for a greenhouse controlled at lower set point of $CO_2$ concentration (500 ${\mu}mol{\cdot}mol^{-1}$) was greater than that of greenhouse at higher set point (800 ${\mu}mol{\cdot}mol^{-1}$). Evaluation tests to optimize $CO_2$ enrichment concluded that the developed control system would be applicable not only to minimize over-exhaust of $CO_2$ but also to maintain the crop profitability.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.4-4
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• 2017

Atmospheric carbon dioxide enrichment ($eCO_2$) often increases soil nitrous oxide ($N_2O$) emissions, but the underlying mechanisms are not fully understood. Emerging evidence suggests that $eCO_2$ alters plant N preference in favor of ammonium ($NH_4{^+}-N$) over nitrate ($NO_3{^-}-N$). Yet, whether and how this attributes to the enhancement of $N_2O$ emissions has not been investigated. We examined the effects of $eCO_2$ on soil $N_2O$ emissions in the presence of two N forms ($NH_4{^+}-N$ or $NO_3{^-}-N$), using wheat (Triticum aestivum L.) as a model plant. Our results showed that N forms dominated $eCO_2$ effects on plant and microbial N utilization, and thus soil $N_2O$ emissions. Elevated $CO_2$ significantly increased the rate and the sum of $N_2O$ emissions by three to four folds when $NO_3{^-}-N$, but not $NH_4{^+}-N$, was supplied. Enhanced $N_2O$ emission was related to the reduced plant $NO_3{^-}-N$ uptake in wheat. We propose a new conceptual model in which $eCO_2$-inhibition of plant $NO_3{^-}-N$ uptake and/or $CO_2$-enhancement of soil labile C enhances the N and/or C availability for denitrifiers and increases the intensity and/or the duration of $N_2O$ emissions. Together, these findings suggest that to enhance plant N use efficiency and reduce $N_2O$ emission, crop breeding and management need to consider altered plant preference of N sources under future $CO_2$ scenarios.

• Journal of Environmental Health Sciences
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• v.33 no.3
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• pp.217-226
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• 2007

The purpose of this study is to estimate the emission factor of $non-CO_2$ global warming gases such as $N_2O$ and $CH_4$ by measuring concentrations from stacks of waste incinerators and cement production plants. Based on the established monitoring methods, $N_2O$ concentration measured from stacks in incinerator were between 0.62 and $40.60\;ppm_v$ (ave. $11.50\;ppm_v$). The concentration of $N_2O$ was dependent on the incinerator types. However, the concentrations of $CH_4$ gas were between 2.65 and $5.68\;ppm_v$ (ave. $4.22\;ppm_v$), and did not show the dependency on the incinerator types. In the cement production plant, the concentration ranges of $N_2O$ from the stack were from 6.90 to $10.80\;ppm_v$ (ave. $8.60\;ppm_v$), and $CH_4$ were between 1.80 and $2.20\;ppm_v$ (ave. $2.60\;ppm_v$). Using measured concentrations, the emission amounts of $N_2O$ and $CH_4$ from stacks per year were calculated. The results were is 4.2 ton $N_2O/yr$ in the incinerators, and 53.7 ton $N_2O/yr$ in the cement facilities. The big difference is from the flow rate of flue gas in the cement facilities compared to the incinerators. By the same reason, the $CH_4$ emission amounts in cement plant and incinerator was found to be 339 ton $CO_2/yr$ and 34.1 ton $CO_2/yr$, respectively. Finally, the emission factor of $N_2O$ in the incinerators were calculated using the measured concentration and the amount of incinerated wastes, and was $42.5\sim799.1\;g/ton$ in kiln and stoker type, $11.9\sim79.9\;g/ton$ in stoker type, 90.1 ton/g in rotary kiln type, 174.9 g/ton in fluidized bed type, and 63.8 g/ton in grate type, respectively. Also, the emission factors of $CH_4$ were found to 65.2-91.3 g/ton in kiln/stoker type, 73.9-122 g/ton in stoker type, 109.5 g/ton rotary kiln, and 26.1 g/ton in fluidized bed type. This result indicates that the emission factor in incinerators is strongly dependent on the incinerator types, and matched with result of IPCC (International Panel on Climate Change) guideline.

• Korean Management Science Review
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• v.26 no.2
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• pp.91-112
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• 2009

Recently, the green business/IT-related issues such as $CO_2$ emission and energy consumption have become spread out rapidly through the world. EU, the United States, Japan and other developed countries are using IT-related environmental regulations as trade barriers. Korea which has high rate of IT exports needs to establish systematic strategies to respond to these environmental regulations. However, it is not easy to find the related research about making green business/IT strategies. This research aims to deduce the green business/IT strategy framework and the suitable green business/IT strategies for the Korean situation. The green business/IT strategy framework is constructed from the analysis of preceding researches and those of the green business/IT strategies of Japan, the United States, and EU. The Korean green business/IT strategies are deduced from survey of experts using Delphi method. We expect that the results contribute to establish the systematic policy and action plan to reduce $CO_2$ emission and energy consumption of IT industry.

• Journal of Climate Change Research
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• v.6 no.4
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• pp.257-265
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• 2015

For estimating a net removal of carbon dioxides from a forest carbon offset project, it is necessary to consider secondary emissions occurred from the use of machineries or vehicles. According to the forest carbon standard in Korea, a default rate (5%) could be applied for estimating secondary emissions of small projects, which provide annual net removals less than or equal to $600tCO_2$, while secondary emissions should be estimated for larger projects with field survey. In this study, we intended to develop a methodology for estimating the secondary emission of a forest carbon project. For this purpose, we analyzed the working process and the carbon emissions of the forest management activities for major tree species in Korea. Based on the developed methodology, we estimated the secondary carbon emission of a reforestation project. The result showed that the secondary carbon emission of a reforestation project was estimated between 0.42% and 1.19 % compared to net removals, that is to say that the current default rate in the forest carbon standard could give an overestimated secondary emission.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.40 no.8
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• pp.503-510
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• 2016

Incinerators generally emit pollutants such as NOx and CO during the combustion process. In this paper, pollutant emissions and temperature distributions were studied in a simulated incinerator with a reversed (relative to the flue gas flow) secondary air injection system. The experiments were performed by using a lab-scale furnace in order to evaluate the effects of the injection location, direction and flow rate of secondary air jets. The emission of NOx was lower in the case of reversed secondary air injection than in the case of cross injection, due to the recirculation and mixing of the exhaust gas. In the reversed air injection cases, thermal NOx emissions decreased as secondary air ratio increased from 30 to 60 and slightly increased at secondary air ratios higher than 60. In most cases, CO emissions were not detected except for a few reversed secondary air injection cases, in which cases CO concentrations below 2ppm were observed.