• Geomechanics and Engineering
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• 제10권3호
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• pp.297-314
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• 2016

With the mining depth continuously increasing, gas emission behaviors become more and more complex. Gas emission is an important basis for choosing the method of gas drainage, gas controlling. Thus, the accurate prediction of gas emission is of great significance for coal mine. In this work, based on the sources of gas emission from the heading faces and the fluid-solid coupling process, we established a gas continuous dynamic emission model, numerically simulated and applied it to the engineering. The result was roughly consistent with the actual situation and shows the model is correct. We proposed the measures of reducing the excavation distance and borehole gas drainage based on the model. The measures were applied and the result shows the overproof problem of gas emission disappears. The model considered the influence factors of gas emission wholly, and has a wide applicability, promotional value. The research is of great significance for the controlling of gas disaster, gas drainage and pre-warning coal and gas outbursts based on gas emission anomaly at the heading face.

• 한국해양환경ㆍ에너지학회지
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• 제4권4호
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• pp.42-50
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• 2001

본 논문에서는 수출입컨테이너 화물의 육상운송에서 연안운송으로의 전환을 이용한 CO₂가스 및 배기가스 배출량 삭감이 제안되어진다. 먼저 국내의 CO₂가스 배출량, 배기가스 배출량, 수출입컨테이너화물의 물동량 등에 대하여 간단히 살펴본다. 또한 경인지역과 부산항사이의 수출입컨테이너화물 수송에 대하여 육상운송에서 연안운송으로의 변환에 의한 CO₂가스 및 배기가스 배출량 삭감효과에 대하여 고찰한다. 마지막으로 연안운송의 분담율 변화와 320TEU 소형컨테이너선 이용에 따른 NOx가스 배출량 변화를 고찰한다. 본 연구의 결과 육상운송에서 연안운송으로의 전환이 CO₂가스 및 배기가스 배출량 삭감에 효과적인 것을 확인하였다.

• 한국안전학회지
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• 제16권4호
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• pp.1-6
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• 2001

An experimental study was carried out to investigate the emission characteristics of LP gas burner for the Practical combustion conditions including fm voltage, inlet area, gas Pressure, emission resistance, duct length and height. The result shows that CO is almost remains constant for the emission fan voltage, but significantly increases with the reduction rate of air inlet, up to 3000ppm at 50% of reduction rate. Also, the variation of gas pressure has no effect to CO of gas boiler due to its governor which controls gas pressure secondly, but it gives an rapid increase of CO for the gas range. The emission resistance test shows that CO is suddenly increased with the reduction rate of emission duct above 70% and main burner is stopped at 90%. The reverse wind test shows that CO is suddenly increased with the air velocity above 7m/s and main burner is stopped at 9m/s. The more horizontal length of emission duct is long and the vertical height is low, CO is infinitesimally increased.

• 한국분무공학회지
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• 제23권4호
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• pp.221-226
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• 2018

Despite the increasingly stringent automotive emissions regulations, the impact of vehicle emissions on air pollution remains large. In addition, since the issue of emission of more exhaust gas than the exhaust gas measured in the test room when the vehicle passing the exhaust gas regulation standard is run on the actual road, many countries studied and introduced gas regulations about Real Driving Emission using Portable Emission Measurement System. At present, Korea regulations restrict the number of NOx and PN in diesel vehicles. In the case of gasoline vehicles, there is no regulation on emission gas, but there is a problem of continuing automobile exhaust gas problems and a large amount of gasoline GDI vehicle's PN emission. So research and interest are increasing due to this problem. In this study, characteristics of exhaust gas depending on changes of ambient temperature were analyzed among various factors affecting exhaust gas measurement of gasoline vehicles. As a result, at the low temperature test, the lower the ambient temperature, the more the exhaust gas was emitted. At ordinary temperature test, no specific tendency was observed due to changes of ambient temperature.

• 한국기후변화학회지
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• 제5권3호
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• pp.209-218
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• 2014

In this study, the researchers have developed the greenhouse gas emission coefficients targeted at sewage sludge incineration plants that treat sewage sludge by incineration. Among the gases emitted from the sewage sludge incineration plants, the greenhouse gases showed concentrations of 6.84% for $CO_2$, 4.51 ppm for $CH_4$, and 86.34 ppm for $N_2O$; calculated into greenhouse gas emission coefficients, these gave $276.06kg\;CO_2/ton$, $0.0066kg\;CH_4/ton$, and $0.35kg\;N_2O/ton$. As the result of calculating the greenhouse gas emission quantity in sewage sludge incineration plants using the greenhouse gas emission coefficients, the gross greenhouse gas emission was $84.63ton\;CO_2\;eq./day$, and the net emission was $23.90ton\;CO_2\;eq./day$; this was $37.52ton\;CO_2\;eq./day$ less than the net greenhouse gas emission that was calculated using the standard values of IPCC, which was $61.42ton\;CO_2\;eq./day$. This difference is probably because unlike the standard values of IPCC, the greenhouse gas emission coefficients of this study reflected the special properties of subject facilities. Thus, it is thought that emission coefficient research on the facilities that deviated from the standard values of IPCC should continue to achieve the development of national greenhouse gas coefficient that reflects the special properties of Korea.

• 한국해양공학회지
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• 제35권6호
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• pp.393-402
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• 2021

As greenhouse gas emissions from maritime transport are increasing, the International Maritime Organization is continuously working to strengthen emission regulations. Liquefied natural gas (LNG) fuel is less advantageous as a point of CO₂ reduction due to the methane leakage that occurs during the bunkering and operation of marine engines. In this study, greenhouse gas emissions from an LNG-fueled ship were analyzed from the perspective of the life cycle. The amount ofmethane emission during the bunkering and operation procedures with various boil-off gas (BOG) treatment methods and gas engine specifications was analyzed by dynamic simulation. The results were also compared with those of other liquid fuel engines. As a result, small LNG-fueled ships without a BOG treatment facility emitted 32% more greenhouse gas than ships utilizing marine gas oil or heavy fuel oil. To achieve a greenhouse gas reduction via a BOG treatment method, a gas combustion unit or re-liquefaction system must be mounted, which results in a greenhouse gas reduction effect of about 25% and 30%. As a result of comparing the amount of greenhouse gas generated according to the BOG treatment method used with each tank size from the perspective of the operating cycle with the amounts from using existing marine fuels, the BOG treatment method showed superior effects of greenhouse gas reduction.

• 한국자동차공학회논문집
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• 제16권2호
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• pp.158-165
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• 2008

The combustion and exhaust emissions characteristics of a liquefied petroleum gas-di-methyl ether compression ignition engine with a variable valve timing device were investigated under various liquefied petroleum gas injection timing conditions. Liquefied petroleum gas was used as the main fuel and was injected directly into the combustion chamber. Di-methyl ether was used as an ignition promoter and was injected into the intake port. Different liquefied petroleum gas injection timings were tested to verify the effects of the mixture homogeneity on the combustion and exhaust emission characteristics of the liquefied petroleum gas-di-methyl ether compression ignition engine. The average charge temperature was calculated to analyze the emission formation. The ringing intensity was used for analysis of knock characteristics. The combustion and exhaust emission characteristics differed significantly depending on the liquefied petroleum gas injection and intake valve open timings. The CO emission increased as the intake valve open and liquefied petroleum gas injection timings were retarded. However, the particulate matter emission decreased and the nitrogen oxide emission increased as the intake valve open timing was retarded in the diffusion combustion regime. Finally, the combustion efficiency decreased as the intake valve open and liquefied petroleum gas injection timings were retarded.

• 한국기후변화학회지
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• 제5권3호
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• pp.219-230
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• 2014

In this study, greenhouse gas emission of magnesium industry was estimated and the reduction potential of the greenhouse gas emission was evaluated with reduction technologies. Default value of IPCC guideline was used to calculate the greenhouse gas emission and $SF_6$ alternatives were considered in reduction potential. Import of magnesium ingot was 22,806 ton in 2013, which will be expected to increase to 81,700 ton with 20% rate in 2020. Magnesium ingot was consumed to produce magnesium alloy in diecasting process. Recently, commercial production of crown magnesium and magensium plate began. Based on ingot consumption, $CO_2$ emission of domestic magnesium industry was estimated to 504,000 ton, which is about 0.79% of domestic industrial emissions. Reduction potential of diecasting process was estimated to 489,320 ton by changing SF6 to alternative gases such as HFC-134a, Novec-612. Emission factor of Tier 3 level should be developed to enhance the accuracy of greeenhouse gas emission of magnesium industry.

• 한국해양환경ㆍ에너지학회지
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• 제6권3호
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• pp.16-25
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• 2003

본 논문에서는 RORO선을 이용한 연안운송에 따른 CO₂가스 배출량과 NOx가스 배출량의 삭감 효과에 대하여 고찰한다. 먼저 국내 CO₂가스 배출량과 수출입 컨테이너화물의 물동량에 대하여 고찰한다. 다음에 RORO선의 특성, CO₂가스 배출량 기준과 NOx가스 배출량 기준에 대하여 고찰한다. 또한 경인지역과 부산항 사이의 수출입 컨테이너 화물의 운송에 있어서 도로운송을 연안운송으로 전환한 경우의 CO₂가스 배출량과 NOx가스 배출량 삭감 효과에 대하여 계산한다. 마지막으로 RORO선의 적재율과 연안운송 분담율 변화에 따른 CO₂가스 배출량과 NOx가스 배출량 변화에 대하여 조사한다. 본 논문의 결과를 통하여 수출입컨테이너 화물의 운송을 도로운송으로부터 RORO선을 이용한 연안운송으로 전환하는 것이 CO₂가스 배출량 삭감에는 효과적이나 NOx가스 배출량 삭감에는 큰 효과가 없는 것을 확인하였다.

• 펄프종이기술
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• 제44권2호
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• pp.49-57
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• 2012

The reduction of greenhouse gas emission currently becomes more urgent task for Korean Industries, especially for the paper industries because of the new regulation based on the low carbon-green growth law. In order to reduce effectively the greenhouse gas emission, the development of greenhouse gas emission inventory has been widely considered as one of the basic processes and has been applied to many industries. In this study, the fundamental schemes and the cases of greenhouse gas inventories were investigated. Especially, the major considering units for paper industries were suggested to develope greenhouse emission inventory of paper industry.