期刊文献+
共找到2篇文章
< 1 >
每页显示 20 50 100
选修课咨询系统的规划与设计
1
作者 刘小东 琊胡滨 王晋华 《电脑知识与技术》 2009年第12期9713-9714,共2页
文章结合专家系统技术、数据库技术,论述了选修课咨询系统开发的必要性,并详细论述了系统的架构模式、总体规划以及设计方法。
关键词 专家系统 数据库 推理机
下载PDF
Development of database of real-world diesel vehicle emission factors for China 被引量:9
2
作者 Xianbao Shen Zhiliang Yao +5 位作者 Qiang Zhang David Vance Wagner Hong Huo Yingzhi Zhang Bo Zheng Kebin He 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2015年第5期209-220,共12页
A database of real-world diesel vehicle emission factors, based on type and technology, has been developed following tests on more than 300 diesel vehicles in China using a portable emission measurement system. The da... A database of real-world diesel vehicle emission factors, based on type and technology, has been developed following tests on more than 300 diesel vehicles in China using a portable emission measurement system. The database provides better understanding of diesel vehicle emissions under actual driving conditions. We found that although new regulations have reduced real-world emission levels of diesel trucks and buses significantly for most pollutants in China, NOx emissions have been inadequately controlled by the current standards, especially for diesel buses, because of bad driving conditions in the real world. We also compared the emission factors in the database with those calculated by emission factor models and used in inventory studies. The emission factors derived from COPERT(Computer Programmer to calculate Emissions from Road Transport) and MOBILE may both underestimate real emission factors, whereas the updated COPERT and PART5(Highway Vehicle Particulate Emission Modeling Software) models may overestimate emission factors in China. Real-world measurement results and emission factors used in recent emission inventory studies are inconsistent,which has led to inaccurate estimates of emissions from diesel trucks and buses over recent years. This suggests that emission factors derived from European or US-based models will not truly represent real-world emissions in China. Therefore, it is useful and necessary to conduct systematic real-world measurements of vehicle emissions in China in order to obtain the optimum inputs for emission inventory models. 展开更多
关键词 Diesel vehicle Emission factor Portable emission measurement system database China
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部