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861.
厂内机动车辆运输安全管理   总被引:1,自引:0,他引:1  
为了保障厂内机动车辆运输安全,防止人员伤害事故的发生,对驾驶人员、厂工、道路及车车辆技术状态等提出了具体要求,并着重提出加强对厂内机动车辆的安全使用管理。  相似文献   
862.
乌鲁木齐市汽车尾气污染现状调查与防治对策   总被引:1,自引:1,他引:0  
对乌鲁木齐市机动车尾气污染现状进行了调查 ,通过大量统计分析 ,其结果表明 ,乌市汽车污染依然严重 ,并提出了防治对策。  相似文献   
863.
This study estimates the effectiveness of a vehicle miles travelled (VMT) tax in controlling mobile-source emissions of particulate matter (PM2.5) in a non-attainment area located in northern Utah. Using a recently updated household-level dataset, the study finds no evidence of an endogenous relationship between choice of vehicle type and VMT. VMT elasticities are also estimated with respect to cost per mile that are in some cases larger in magnitude than those reported in previous studies. Based on vehicle emissions tests performed by the Houston Advanced Research Center, the study estimates the reduction in particulate emissions that would occur with two different sets of VMT tax rates. Principal findings are that a VMT tax rate of $0.003 per passenger car mile and $0.01 per light-duty truck mile (resulting in a mean annual tax burden of $128 per household in the first year) would reduce annual particulate emissions by between 7% and 11%, depending upon the degree of heterogeneity in household driving behaviour. Assuming constant elasticity, this means that at tax rates of $0.006 and $0.02 per mile for passenger cars and light-duty trucks, respectively (resulting in double the mean annual tax burden), annual particulate emissions would be reduced by between 12% and 23%. Both the advantages and limitations of the VMT tax are discussed.  相似文献   
864.
温度/湿度组合循环试验本质上是一项气候环境的加速试验,失效较为集中。这里列出了若干关于试验的要点,供产品研发和试验人员把握。  相似文献   
865.
汽车尾气净化减排技术进展   总被引:2,自引:0,他引:2  
评述了国内外汽车尾气净化减排技术的新进展及应用情况。  相似文献   
866.

Problem

Alcohol-related youth traffic fatalities continue as a major public-health concern. While state and federal laws can be useful in tackling this problem, the efficacy of many laws has not been empirically demonstrated. We examined the impact of state laws prohibiting alcohol advertising to target minors. Method: Using statistics obtained from the Fatality Analysis Reporting System (FARS), youth alcohol-related, single-vehicle, driver traffic fatalities were compared by state as a function of whether the state has a law prohibiting alcohol advertising that targets minors. Results: Overall, states possessing this law experienced 32.9% fewer of the above specified traffic fatalities. Discussion and Impact on Industry: The results suggest that not only are youth drinking rates affected by alcohol advertisements targeting youth, but also drink-driving behaviors. Indeed, we estimate that if this type of legislation were adopted in the 26 states that do not prohibit targeting of minors with alcohol advertising, then 400 youth lives could be saved annually.  相似文献   
867.
汽车行人碰撞接触中行人运动学规律仿真研究   总被引:6,自引:2,他引:4  
基于交通事故模拟分析PC-Crash软件及其内嵌多体系统动力学分析MADYMO模块,建立并验证了车辆多体模型和行人多体模型;对汽车与行人碰撞接触阶段的行人运动学具有较大影响的因素展开广泛分析,并构建汽车行人碰撞仿真试验方案;通过选取对汽车与行人碰撞接触阶段具有较大影响的因素作为仿真试验的自变量,对不同碰撞环境下汽车与行人碰撞接触过程中的行人运动学规律(包括运动姿态和对应的碰撞车速阈值)进行深入研究;汽车行人碰撞仿真与真实事故以及碰撞试验对比具有较好的规律吻合性和一致性。研究表明,笔者采用的计算机建模仿真方法在汽车行人碰撞运动学研究中具有实用价值。  相似文献   
868.
Air samples were collected in Izmir, Turkey at two (suburban and urban) sites during three sampling programs in 2002 and 2004 to determine the ambient concentrations of several monoaromatic, chlorinated and oxygenated volatile organic compounds (VOCs). Samples were analyzed for 60 VOCs using gas chromatography/mass spectrometry and 28 compounds were detected in most samples. On the average, urban air VOC concentrations were about four times higher than those measured at the suburban site. Toluene (40.6%) was the most abundant compound in suburban site and was followed by benzene (7.4%), o,m-xylene (6.5%), and 1,2-dichloroethane (5.1%). In urban site, toluene (30.5%), p-xylene (14.9%), o,m-xylene (11.4%), and ethyl benzene (7.2%) were the dominating compounds in summer. In winter, toluene (31.1%), benzene (23.9%), 1,2-dichloroethane (9.5%), and o,m-xylene (8.2%) were the most abundant compounds. Receptor modeling (positive matrix factorization) has been performed to estimate the contribution of specific source types to ambient concentrations. Six source factors (gasoline vehicle exhaust, diesel vehicle exhaust+residential heating, paint production/application, degreasing, dry cleaning, and an undefined source) were extracted from the samples collected in the urban site. Three source factors (gasoline vehicle exhaust, diesel vehicle exhaust, and paint production/application) were identified for the suburban site.  相似文献   
869.
为调查马鞍山市城区主干道近地面空气质量状况,马鞍山市环境监测中心站于1999年1月19日~1月21日对城区3条主干道的5个监测点近地面空气质量进行了监测.结果表明,在城市整体环境空气质量良好的情况下,交通干道近地面空气污染较严重,主要污染源是机动车尾气,NOx、CO、TSP是特征性污染物,其中NOx平均分布浓度与车流量近似成正相关,从时间分布上看,NOx平均分布浓度早上最高,晚上次之,中午最低.指出,为改善城市的环境空气质量,必须加强对机动车尾气的监督管理.  相似文献   
870.
以南京市为例,依托机动车环保监管数据库,根据国家机动车排放模型CVEM计算出黄标车主要污染物一氧化碳、碳氢化合物、氮氧化物及颗粒物的年排放量,并系统回顾了近年来为控制黄标车污染所采取的区域限行、淘汰奖补和治理改造等针对性管理措施,分析了政策实施的进展及成效,进一步明确了黄标车治理的必要性。  相似文献   
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