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Introduction China is experiencing rapid economic and populationgrowth. The rapid growth and increasing fossil fuel energyconsumption have resulted in large amounts of pollutants suchas TSP, SO2, NOx and hydrocarbons to be emitted intoambient atmosphere. Nowadays, national routine monitor haspaid much attention to TSP, SO2 and NOx. Highconcentrations of SO2 and NOx can lead to an increase ofregional levels of acid deposition and tropospheric ozon, thu… 相似文献
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机动车尾气的产生及对人群健康的影响和防治对策 总被引:5,自引:0,他引:5
较详细的介绍了机动车燃料和尾气的关系,全面论述了尾气中主要污染物对人体健康的危害,并对防治尾气的污染提出了建议。 相似文献
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A remote sensing system of vehicle emissions based on tunable diode laser technology 总被引:2,自引:1,他引:1
As being an effective real-time method of monitoring vehicle emissions on-road, a remote sensing system based on the tunable diode laser (TDL) technology was presented, and the key technologies were discussed. A field test in Guangzhou(Guangdong, China) was performed and was found that the factors, such as slope, instantaneous speed and acceleration, had significant influence on the detectable rate of the system. Based on the results, the proposal choice of testing site was presented. 相似文献
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车流量是移动源和道路扬尘排放清单计算的一个重要参数,直接影响排放清单的不确定性.为了解天津市道路车流量特征,通过人工摄录法获取天津市一年四季5种不同类型共9条道路的车流量及车型分布信息,并对其特征进行分析.结果表明:天津市不同类型道路之间车流量总体上呈快速路(8 790辆/h)>主干道(4 077辆/h)>外环线(3 335辆/h)>次干道(2 461辆/h)>支路(1 507辆/h)的特征;冬季车流量最大,而春、夏两季相对较小.各类型道路车流量占比最大的车型均为轻型车(76.88%~90.71%),中型车(5.31%~11.80%)次之,重型车(3.20%~11.31%)最少;快速路和外环线工作日的车流量大于非工作日,并且差异具有统计学意义,呈"周末效应".研究显示:次干道和支路车流量与主干道车流量呈线性相关,在后续进行道路扬尘和移动源清单编制时,可以考虑通过将主干道车流量与次干道、支路拟合的方式减小工作量;此外,主干道、次干道和支路的早高峰,上、下午平峰,中午和晚高峰的车流量差异不大,可将一天划分为白天、夜晚和凌晨3个时段进行统计,从而节约时间和成本. 相似文献
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Rachel Lovely Andrew Trecartin Gabe Ologun Alexander Johnston Sergy Svintozelskiy Francoise Vermeylen 《Traffic injury prevention》2018,19(8):S167-S168
ABSTRACTObjective: This study aims to identify the association, if any, between prehospital scene time, prehospital transport time, and Injury Severity Score (ISS) with in-hospital mortality.Methods: A retrospective analysis was performed on patients at least 18 years of age who arrived to the hospital alive via emergency medical services (EMS) after a motor vehicle collision (MVC) between 1992 and 2016. These patients were divided into groups based on minutes spent at the scene and in transport. The ISS of the in-hospital mortalities, as well as the entire patient sample for each time frame, was collected. Patients without documented scene time, transport time, or ISS were excluded.Results: Four thousand one hundred ninety-four patients were captured when analyzing scene time, though only 3,980 met inclusion criteria. In addition, 4,177 patients were captured when analyzing transport time, though only 3,979 met inclusion criteria. Scene time and transport time were not statistically significant predictors of in-hospital mortality (P = .31 and P = .458, respectively). ISS was found to be a statistically significant predictor of in-hospital mortality (P < .001).Conclusions: ISS predicts mortality independent of scene time or transport time for patients who arrive to the hospital alive following an MVC at Guthrie Robert Packer Hospital. Limitations of our study include inability to capture prehospital deaths and inability to correlate ISS with prehospital injury severity scores. 相似文献
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为了实时检测无人机异常状态,提出基于隐马尔可夫模型(Hidden Markov Model,HMM)和决策树(Decision Tree,DT)的无人机异常检测方法(HMMDT).首先根据异常致因将无人机异常分为干扰异常和硬件异常;然后结合HMM和DT建立无人机异常检测模型,定义无人机异常度衡量异常状态的严重程度,确定... 相似文献