• 동력기계공학회지
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• 제8권1호
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• pp.18-23
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• 2004

The direct injection diesel engine is one of the most efficient thermal engines. For this reason DI diesel engines are widely used for heavy-duty applications. But the world is faced with very serious problems related to the air pollution due to the exhaust emissions of diesel engine. So, that is air pollution related to exhaust gas resulted from explosive combustion should be improved. Exhaust Gas Recirculation(EGR) is a proven method to reduce NOx emissions. In this study, the experiments-were performed at various engine loads while the EGR rates were set from 0% to 20%. The emissions trade-off and combustion of diesel engine are investigated. Hot and cooled EGR are achieved without cooling and with cooling respectively. It was found that the exhaust emissions with the EGR system resulted in a very large reduction in oxides of nitrogen at the expense of higher smoke emissions. Also, the reduction rates of NOx emissions for hot and cooled EGR are similar at load 20%.

• Environmental Analysis Health and Toxicology
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• 제16권2호
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• pp.75-84
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• 2001

Differences in risk perception on major environmental issues between general public and environmental experts were investigated in this study. Questionnaire surveys were conducted to samples from general public and environmental experts during March and April, 2000. Total number of responses was 1,126 including 773 persons from general public and 353 experts. Risk perceptions on 26 environmental issues were related with the need to regulate each issue, controllability, experience, political views, interest in environmental problem, satisfaction of environment, severity of environmental pollution. There was statistically significant difference in risk perceptions between general public and experts. Overall, general public was likely to perceive risks associated with environmental problem, as well as social need to regulate these problems more than experts. The issues with high risk perception and need to regulate were 'automobile exhaust', 'industrial air pollution', ocean pollution by industrial waste and oil exhaust', 'air pollution by chemicals', 'surface water pollution by waste from household', 'industrial and hospital waste', 'surface water pollution by pesticide'and'sewage and food waste'. Consequently, it seems necessary to manage these issues, prior to others.

• 한국자동차공학회논문집
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• 제13권5호
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• pp.188-194
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• 2005

The direct injection diesel engine is one of the most efficient thermal engines. For this reason DI diesel engines are widely used for heavy-duty applications. But the world is faced with very serious problems related to the air pollution due to the exhaust emissions of diesel engine. So, that is air pollution related to exhaust gas resulted from explosive combustion should be improved. Exhaust Gas Recirculation(EGR) is a proven method to reduce NOx emissions. In this study, the experiments were performed at various engine loads while the EGR rates were set from $0\%$ to $30\%.$ The emissions trade-off and combustion of diesel engine are investigated. The brake specific fuel consumption rate is very slightly fluctuated with EGR in the range of experimental conditions. The ignition delay increased with increasing EGR rate. The maximum value of premixed combustion for the rate of heat release is increased with increasing EGR rate. NOx emissions are decreased with increasing EGR rate at high load and high speed. It was found that the exhaust emissions with the EGR system resulted in a very large reduction in oxides of nitrogen at the expense of higher smoke emissions.

• 에너지공학
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• 제24권3호
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• pp.34-39
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• 2015

Recently, Air pollution is gradually increasing which are coming from the exhaust of the ICE vehicles in the world. ICE vehicle exhaust gas and $CO_2$ are widely suspected of contributing to the called greenhouse effect, fueling fears of global warming. Therefore, many countries are striving to decrease the vehicle exhaust gas and have developed a variety of policies as air pollution regulation plans. To comply with the regulations, automotive industry has developed hybrid vehicles, which have features of both ICE vehicles and electric vehicles. Hybrid car is eco-friendly and has lowered exhausting gases and improved fuel efficiency. This research has been written to show that break down cases with EGR valve in hybrid cars, steadily increasing in use, and to help with on-site maintenance.

• 한국대기환경학회지
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• 제27권2호
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• pp.181-190
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• 2011

The air pollutants from vehicle exhaust gas are affected by many factors including fuel qualities, engine and vehicle technologies, driving patterns. In particular, fuel qualities and after-treatment devices could directly affect the emission level of pollutants. The pollutant reduction characteristics that caused by enforced fuel quality standard were analyzed. Three types of test fuel were selected in accordance with Korean automotive fuel standard in 2006, 2009, 2012 and used for vehicle emission test in chassis dynamometer. European COPERT correction equation of fuel impact was considered as reference information to quantify the vehicle emission test results. The contribution rates of exhaust emission by COPERT correction equation showed that aromatic compounds and oxygen contents in gasoline fuel was most important. In case of diesel fuel, cetane index and polycyclic aromatic compounds accounted for the greater part. The exhaust emission effects by COPERT correction equation revealed that CO and VOC was increased 0.86%, 1.57% respectively in after 2009 gasoline when compared to before 2009 gasoline fuel. In case of light-duty diesel vehicle CO, VOC and PM were decreased in range of 3~7%. The result from this study could be provided for developing future fuel standards and be used to fundamental information for Korean clean air act.

• 대한교통학회지
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• 제25권6호
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• pp.89-97
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• 2007

고도의 산업화와 경제발전으로 인한 자동차 의존적인 교통체계는 도심의 교통혼잡, 에너지소비, 대기오염과 소음, 교통사고 등과 같은 많은 문제를 유발하고 있는 실정이다. 특히, 도심에서 자동차로 인한 대기오염은 과거 산업활동에 의해 발생된 공해문제보다 더욱 심각한 수준에 이르고 있다. 이에 본 연구에서는 미시적 시뮬레이션을 이용하여 자동차 배출가스 저감 효과를 파악하고 경제성 분석을 통해 도심지에서 대기오염을 최소화 하면서 차량 소통을 원활히 할 수 있는 교통정책이 무엇인지를 파악하였다. 그 결과, 차량 요일제가 투자비용이 없어 가장 효과적인 방법인 것으로 나타났으나 시민들에게 강제성을 부여함으로써 자동차 수요를 억제시키기 때문에 시민들과의 공감대 형성이 무엇보다 중요하며, 다른 대안들과 병행하여 추진하는 것이 효과적일 것이라는 결론을 얻었다. 향후 연구과제는 선호의식 조사를 통해 시민들이 생각하는 자동차 배출가스의 대기오염 영향을 조사하고 본 연구 결과를 통해 나타난 차량 요일제 도입시 참여 의사를 조사하여 실제 교통정책 도입 가능성 등을 파악하는 연구를 진행 해야겠다.

• Asian Journal of Atmospheric Environment
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• 제1권1호
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• pp.1-8
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• 2007

Vehicle exhaust is a dominant source of air pollutants in urban areas. Since people are easily exposed to vehicle exhaust particles while driving a car and/or traveling via public transportation, air pollution near traffic has been extensively studied in developed countries. In this paper, investigations on vehicle-related fine particulate air pollution at roadsides and on roads in Seoul, Korea were reviewed to understand air pollution near traffic. Comparison of $PM_{10}$ concentrations in Seoul showed that roadside air is more contaminated than urban air, implying that exposure levels near vehicular emissions are more critical to sensitive persons. Concentrations of ultrafine particles and BC (black carbon) at roadsides of Seoul fluctuate highly for short durations, responding to traffic situations. Diurnal variations of ultrafine particles and BC concentrations at roadsides seem to be affected by traffic volume, mixing layer height, and wind speed. Concentrations of ultrafine particles and BC decrease as distance from the road increases due to dilution during transport. On-road air pollution seems to be more severe than roadside air pollution in Seoul. Since nearby traffic air pollution has not been well understood in Seoul, further studies including various vehicular air pollutants and representative locations are needed.

• 전기의세계
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• 제26권2호
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• pp.95-98
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• 1977

Commercially available fuel oil for power plant contains relatively much sulphur, which means accordingly high content sulphur deoxide in exhaust gas. Sulphur deoxide has been identified as the worst-pollutant caused by thermal power generation. This paper primarily deals with the stack gas diffusion effects of various parameters, namely vertical stability, wind velocity, exhaust gas velocity, stack height, etc., on the ground concentration. thereof the relation between stack height and maximum plant capacity is analyzed from the standpoint of air pollution prevention. The limit capacity is calculated by means of mean concentration introducing Mead and Lowry coefficient respectively.

• 해양환경안전학회지
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• 제2권S1호
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• pp.77-85
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• 1996

As conservation of global environment has becoming a major outstanding issue of the world, the International Maritime Organization(IMO) has been legislation a convention for prevention of air pollution from ships. By the new convention, use of air pollutants such SOx, NOx, Freon and Halin Gas shall be restricted. In this regards, analysing these requirements of the convention is required as the cinvention will also be applied in restriction of descharging exhaust gases from ships by estsblishing a requirement of Sox and NOx discharged. The purpose of this study is as follows; 1) Introdcuing of the backgrounds of legislating the convention for prevention of air pollution from ships and major contents of the convention and a countermeasuures in the convention by Korea 2) Reviewing by analyzing the influence in domestic industries concernd by restriction of SOx, NOx in exhaust gases and sulpher content of fuel oil 3) Preparing a countermeasure in the convention properly.

• Journal of Advanced Marine Engineering and Technology
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• 제20권2호
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• pp.69-69
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• 1996

As conservation of global environment has becoming a major outstanding issue of the world, the International Maritime Organization(IMO) has been legislation a convention for prevention of air pollution from ships. By the new convention, use of air pollutants such as SOx, NOx, Freon and Halon Gas shall be restricted. In this regards, analysing these requirements of the convention is required as the convention will also be applied on restriction of discharging exhaust gases from ships by establishing a requirement of SOx and NOx discharged. The purposed of this study is as follows ; 1) Introducing of the backgrounds of legislating the convention for prevention of air pollution from ships and major contents of the convention and a countermeasures on the convention by Korea. 2) Reviewing by analyzing the influence on domestic industies concerned by restriction of SOx, NOx in exhaust gases and sulphur content of fuel oil. 3) Preparing a countermeasure on the convention properly.