통합 검색 | Korea Science

장세호
- 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%.
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김현성;김선아;박선규
- 한국건축시공학회:학술대회논문집
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- 한국건축시공학회 2018년도 추계 학술논문 발표대회
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- pp.29-30
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- 2018
The development of the industry has increased the indoor living time of modern people. Therefore, indoor pollution is attracting attention as a social issue. One of the indoor air pollution is formaldehyde. Formaldehyde has been classified as a first-level carcinogen by international cancer research organizations. Formaldehyde has been used to protect products such as construction materials and finish materials, and being diffused in the interior construction process. In this study, we used phytoncide with cement matrix to reduce formaldehyde, an indoor environmental contaminant. The strengths was increased slightly and formaldehyde showed a reduction effect over time.
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박완규;안건영
- 한국조경학회지
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- 제26권3호
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- pp.225-236
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- 1998
The purpose of this study is to identify the important evaluatio items for developing the environmental sustainability indices of housing estate. In this research, the principles of environmental sustainability were established on the concept of ESSD, and twenty-two evaluation items were explored on the basis of questionnaire of experts, the twenty-two items are ranked in order of iportant level and it is a appeared that 'development density' is most iportant evaluation item. In conclusion, twelve important items were selectd; 'development density', 'preservation of natural forest and topography' , 'amount of green area', 'reduction of water pollution','reuse of wastes','garbage discharge','reduction of air pollution','distribution of land use','rainwater infiltraton and preservaton of underground water','site planning for energy saving','separated collection of wastes','access to natural forest andwaters around housing estate'
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