• 한국자동차공학회논문집
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• 제15권3호
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• pp.166-173
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• 2007

A numerical study was conducted to have the effect of $CO_2$ addition to fuel on the chemical reaction mechanism with the change of the initial concentration of $CO_2$ and the axial velocity gradient. From this study, it was found that there were two serious effects of $CO_2$ addition on a non-premixed flame ; a diluent effect by the reactive species reduction and chemical effect of the breakdown of $CO_2$ by the third-body collision and thermal dissociation. Especially, the chemical effect was serious at the lower velocity gradient of the axial flow. It was certain that the mole fraction profile of $CO_2$ was deflected and CO was increased with the initial concentration of $CO_2$. It was also ascertained that the breakdown of $CO_2$ would cause the increasing of CO mole fraction at the reaction region. It was also found that the addition of $CO_2$ did not alter the basic skeleton of $H_2-O_2$ reaction mechanism, but contributed to the formation and destruction of hydrocarbon products such as HCO. The conversion of CO was also suppressed and $CO_2$ played a role of a dilution in the reaction zone at the higher axial velocity gradient.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.1117-1121
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• 2008

Recently energy consumption and $CO_2$ emission issue are important problem on international society. The present study has been conducted economic analysis considering economical value of $CO_2$ reduction effect. We analyze annual energy cost and annual $CO_2$ emission of the cogeneration system and gas boiler system in hotel. The first results shows that annual energy cost of cogeneration system (751,740,126 won) is more profitable than gas boiler system (801,128,408 won) by 6.2% (49,388,281 won). The second results shows that annual $CO_2$ emission of cogeneration system (3,297 ton) is less than gas boiler system (3,536 ton) by 6.8% (239 ton). The Economical value of $CO_2$ reduction effect is 4,773,898 won. The cost effect according to the reduction of $CO_2$ is corresponding to 9.7% of reduction cost for total energy cost. The result of this study means that $CO_2$ reduction effect is essential item in introduction and change of facility for economic analysis.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.2921-2927
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• 2011

Modal Shift from road to rail has been adapted in several countries as one of effective ways of reducing $CO_2$ emissions caused by transport. Generally, effect analysis of $CO_2$ reduction toward modal shift is calculated mainly from use stage and less consideration from other stages of life cycle, even though, in some case of modal shift needs that new line construction or new vehicle manufacturing. In this study, modal shift effect analysis is performed with considering construction, manufacturing vehicle and use stage. As a result we can get total $CO_2$ reduction effect using life cycle thinking and check the necessity of including other life cycle stage not only considering use stage. In conclusion, there is no $CO_2$ reduction effect if the reduction amount of $CO_2$ in use stage is not bigger than allocated annual amount of $CO_2$ in construction and manufacturing vehicle stage. According to this fact, analysing $CO_2$ reduction effect of Modal Shift should be considered not only the use stage.

• 한국연소학회지
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• 제4권2호
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• pp.97-108
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• 1999

This numerical study was to investigate the effect of $CO_2$ addition on the structures and NOx formation characteristics in $CH_4$ counterflow diffusion flame. The importance of radiation effect was identified and $CO_2$ addition effect was investigated in terms of thermal and chemical reaction effect. Also the causes of NOx reduction were clarified by separation method of each formation mechanisms. The results were as follows : The radiation effect was intensified by $CO_2$ addition. Thermal effect mainly contributed to the changes in flame structure and the amount of NO formation but the chemical reaction effect also cannot be neglected. The reduction of thermal NO was dominant with respect to reduction rate, but that of prompt NO was dominant with respect to total amount.

• Korean Chemical Engineering Research
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• 제51권5호
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• pp.602-608
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• 2013

$CO_2$를 포집, 수송, 저장하는 기술에 있어서 경제적이고 친환경적 혁신기술로 주목받고 있는 가스 하이드레이트 이용기술의 연구가 활발히 진행되고 있다. 본 연구에서는 가스 하이드레이트를 이용한 $CO_2$ 수송/저장기술의 핵심이 되는 자기보존효과(self-preservation effect)가 발현하는지를 확인하고자 하였다. 특히 $CO_2$ 하이드레이트 입자의 직경에 대한 효과 정도를 실험적으로 살펴보았다. 밀리미터, 마이크론, 그리고 나노 크기의 각각 다른 직경을 갖는 세 종류 $CO_2$ 하이드레이트 샘플을 준비하였고, 3주간 $-15{\sim}-30^{\circ}C$의 온도 및 대기압 조건에서 각각의 샘플 무게 변화를 측정하였다. 실험연구 결과 $CO_2$ 하이드레이트의 자기보존효과를 최대한 얻기 위해서는 온도는 가능한 낮아야 하며, 샘플의 직경 크기가 클수록 좋고, 샘플은 치밀한 구조로 조직되어 높은 밀도를 갖는 방식으로 제조하는 것이 매우 향상된 결과를 얻을 수 있음을 확인하였다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.1389-1394
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• 2003

$CO_2$ is a well-known green house gas, which is the major source of global warming. Many researchers have studied to reduce $CO_2$ emission in combustion processes. Among the method for reducing $CO_2$ emission, oxygen-enriched combustion has been proposed. But the adiabatic flame temperature is too high. So existing facilities must be changed, or the adiabatic flame temperature in the combustion zone should be reduced. The combustion characteristics, composition in the flame zone, temperature profile and emission gases were studied experimentally for the various oxygen-enriched mtios(OER) by addition of $CO_2$ under coustant $O_2$ flowrate. Results showed that the reaction zone was quenched, broadened, as addition of $CO_2$ was increased. Temperature has a large effect on the NOx emission. The emission of NOx in flue gas decreased due to the decreased temperature of reaction zone. It was also shown that the reaction was delayed by the cooling effect. As the addition of $CO_2$ was increased, the composition of CO in the flame zone increased due to the increase of reaction rate by increasing mixing effect of oxidant/fuel at OER=0, but the composition of CO decreased by quenching effect at OER=50 and 100%.

• 한국전자거래학회지
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• 제15권3호
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• pp.163-181
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• 2010

최근 온난화 현상에 따른 범세계적 위기가 초래됨에 따라 선진국을 중심으로 교토의정서가 체결되었으며, 이를 계기로 온실가스 규제가 본격화되기 시작하였다. 또한 교토의정서의 교토유연성체계라는 시장메커니즘이 도입되어 온실가스 배출에 대한 소유권이 설정되고, 수급에 따라 배출권 가격이 형성되는 등 새로운 무형의 자원을 거래하는 탄소시장이 등장하게 되었다. 학계에서는 탄소배출효과를 측정하는 방법론과 이를 탄소배출권의 경제적 비용으로 전환하고자 하는 연구들이 태동하기 시작하였다. 본 연구에서는 전자정부 정보화사업 중 하나인 G2B 시스템을 통해 전통적인 조달업무 프로세스가 온라인화 됨에 따라 저감되는 탄소 배출저감효과 즉, e-transformation화에 따른 탄소저감효과를 측정하는 ECRE(Evaluation of $CO_2$ Reduction in E-transformation)모델과 절차를 제시하고자 한다. ECRE 모델은 세계 기후협의체(IPCC)의 방법론을 근간으로 하여 크게 '이동 수단에 따른 탄소저감효과', '종이 문서 절감에 따른 탄소저감효과' 2가지의 탄소배출량을 측정하고 이를 탄소배출권의 경제적 비용으로 환산한다. 또한 본 연구에서는 탄소저감효과를 효과적으로 측정하기 위하여 5단계와 10개의 세부절차로 구성된 절차를 제시하였다. 본 연구에서 제시한 ECRE 모델과 절차를 이용하여 정부기관은 물론 온실가스 규제를 받게 되는 에너지 환경기업 등에서 정보화사업을 통한 탄소감축 실적의 추정 및 추가적인 정보화사업 추진으로 기대되는 탄소저감효과를 사전에 시뮬레이션해 볼 수 있는 도구로서 활용이 기대된다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집B
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• pp.149-154
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• 2001

The emission characteristics, flame stability, the composition of the flame zone and temperature profile were studied experimentally. The compositions of oxydant were varied by substituting $N_2$ with $CO_2$ at the constant $O_2$ concentration. Results showed that flame became unstable due to the high heat capacity, low transport rate and strong radiation effect of $CO_2$ in comparison with those of $N_2$. The reaction zone was cooled, broadened, as the conversion ratio of $CO_2$ to $N_2$ was increased. Temperature has a large effect on the NOx emission. The concentration of NOx in flue gas decreased due to the decreased temperature of reaction zone. It was also shown that the reaction was delayed by the cooling effect. As the conversion ratio of $CO_2$ to $N_2$ was increased, the emission of CO and the higher temperature zone increased due to the decrease of reaction rate by the cooling effect.

• 한국IT서비스학회지
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• 제12권2호
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• pp.73-84
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• 2013

The development of the information on the internet brought a lot of changes in the real estate market. Because the real estate has local distinctiveness and individuality household who want to move must to visit place for housing information. But now household use internet real estate information at every decision-moving step and that is able to reduce not only the cost of real estate information but also social benefit like $CO_2$ emissions reduction effect. In this study, I analyzed the effect of $CO_2$ emissions reduction with Seoul household residential mobility data when household take informations from internet real estate site. As increasing a single family who is good at internet service, the effect of $CO_2$ reduction from the development of the Internet real estate information has more increased.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 춘계 학술발표회
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• pp.291-294
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• 2010

$CO_2$ is known as the major source of the green house effect and the volume produced from electricity generation and transportation sector in Korea constitutes the large portion. In order to reduce the green house effect, several treatment methods can be the major research topics such as the scheme to fundamentally restrict the production of $CO_2$ creation, to perfectly sequestrate the produced $CO_2$, to reuse the separated $CO_2$, or to permanently dispose $CO_2$ in an appropriate storage site. Among of them, R&D strategy and geotechnical research issues are explored in this paper in an effort to realize geological storage for the sequestrated $CO_2$ in local storage sites. $CO_2$ is known as the major source of the green house effect and the volume produced from electricity generation and transportation sector in Korea constitutes the large portion. In order to reduce the green house effect, several treatment methods can be the major research topics such as the scheme to fundamentally restrict the production of $CO_2$ creation, to perfectly sequestrate the produced $CO_2$, to reuse the separated $CO_2$, or to permanently dispose $CO_2$ in an appropriate storage site. Among of them, R&D strategy and geotechnical research issues are explored in this paper in an effort to realize geological storage for the sequestrated $CO_2$ in local storage sites.