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901.
902.
Ryan C. Smith Author Vitae E. Scott Geller Author Vitae 《Journal of Safety Research》2009,40(5):359-364
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903.
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
904.
Characterization of Volatile Organic Compounds (VOCs) and Their Sources in the Air of Izmir, Turkey 总被引:1,自引:0,他引:1
Elbir T Cetin B Cetin E Bayram A Odabasi M 《Environmental monitoring and assessment》2007,133(1-3):149-160
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
905.
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
906.
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
907.
建立了固相微萃取与车载气相色谱-质谱联用技术现场快速定量分析突发性水环境污染事故中的硝基苯、苯酚、苯胺3种半挥发性有机物的方法。选用PA萃取纤维,调节水样p H为8.5,加入30%的氯化钠,45℃顶空萃取30 min可得最佳萃取效果。在最佳实验条件下,硝基苯、苯酚、苯胺的方法检出限分别为0.68、3.2、4.88μg/L;平行测定7次的相对标准偏差分别为5.37%、8.31%、2.86%;3种化合物的相关性系数均大于0.99;对实际样品测定的加标回收率在61.1%~120%。 相似文献
908.
无人机载核辐射监测及气溶胶采样系统试验分析 总被引:2,自引:0,他引:2
利用旋翼式无人机平台挂载机载式γ谱仪、气溶胶采样器及相关监控设备,在稳定风场下开阔平坦场地,对特征金属颗粒物随炸药爆炸后形成的气溶胶进行空中烟云跟踪取样及巡测,测量环境核辐射水平。结果表明,通过8次爆炸物气溶胶跟踪采样,以及放射性点源探测试验,证实旋翼式无人机空中气溶胶取样及对辐射测量的可行性。 相似文献
909.
Traffic speeds associated with implementation of 80 mph speed limits on West Texas rural interstates
Richard Retting Author Vitae Ivan Cheung Author Vitae 《Journal of Safety Research》2008,39(5):529-534
Problem
In 2006 Texas raised the daytime speed limit for passenger vehicles on segments of I-10 and I-20 from 75 to 80 mph. Methods: Traffic speeds were measured before and 3, 12, and 16 months after the limit was changed. Results: During the 16-month period following the speed limit increase, mean speeds of passenger vehicles on I-20 increased by 9 mph relative to the comparison road, where no speed limit change occurred and traffic speeds declined. On I-10 mean speeds increased by 4 mph relative to the comparison road. Limiting the analysis to the month before the speed limit change and 1 year later, the proportion of drivers exceeding 80 mph was 18 times higher on I-20 and 2 times higher on I-10. Discussion: The smaller speed increases on I-10 may be related to its proximity to the U.S. border with Mexico. Highly visible border patrol activity coincided with posting of the higher speed limit. Long-term monitoring in other states suggests that traffic speeds in Texas are likely to continue to increase. Impact on Industry: The present study adds to the wealth of evidence that increased speed limits lead to increased travel speeds. The primary countermeasures to reduce the risk of speed-related crashes include highly visible police traffic enforcement and the use of speed cameras accompanied by publicity. 相似文献910.
Brian C. Tefft Author Vitae 《Journal of Safety Research》2008,39(6):577-582