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31.
主要介绍汽车整车自然暴露试验评价方法,基于整车厂长期进行汽车整车自然暴露试验,对整车进行表观检测、性能检查及其他项目检测,通过分析试验结果,归纳汽车内外饰件常见缺陷,按照失效程度和不同部件类型,为整车耐候性进行等级划分,建立整车系统化评价方法。  相似文献   
32.
Objective: Road traffic suicides typically involve a passenger car driver crashing his or her vehicle into a heavy vehicle, because death is almost certain due to the large mass difference between these vehicles. For the same reason, heavy-vehicle drivers typically suffer minor injuries, if any, and have thus received little attention in the research literature. In this study, we focused on heavy-vehicle drivers who were involved as the second party in road suicides in Finland.

Methods: We analyzed 138 road suicides (2011–2016) involving a passenger car crashing into a heavy vehicle. We used in-depth road crash investigation data from the Finnish Crash Data Institute.

Results: The results showed that all but 2 crashes were head-on collisions. Almost 30% of truck drivers were injured, but only a few suffered serious injuries. More than a quarter reported sick leave following their crash. Injury insurance compensation to heavy-vehicle drivers was just above €9,000 on average. Material damage to heavy vehicles was significant, with average insurance compensation paid being €70,500. Three out of 4 truck drivers reported that drivers committing suicide acted abruptly and left them little opportunity for preventive action.

Conclusions: Suicides by crashing into heavy vehicles can have an impact on drivers’ well-being; however, it is difficult to see how heavy-vehicle drivers could avoid a suicide attempt involving their vehicle.  相似文献   

33.
Through a sensitivity analysis, the trade-off between vehicle range and CO2 emissions is investigated as a function of electric emissions coefficient. Various powertrains were analysed for use in a small crossover sport utility vehicle. Gasoline, gasoline electric hybrid, diesel, fuel cell and battery electric vehicles (BEVs) were considered. Using various upstream fuel pathways and a model for vehicle performance, emissions and energy use were estimated. The hydrogen fuel cell vehicle was found preferable to BEVs under conditions of high CO2 emissions per kW-hr and a high vehicle range requirement. The BEV was preferable for all other conditions.  相似文献   
34.
重庆市内环货车错时限行对空气质量的影响   总被引:1,自引:1,他引:0  
在分析货车实施错时限行后内环车流量时段分布变化基础上,通过对PM_(2.5)、NO_2等指标的ADMS模型模拟和实际监测数据对比分析,探讨了内环货车错时限行对环境空气质量的影响。结果表明,货车错时限行后主城区环境空气中PM_(2.5)、NO_2小时平均质量浓度分别降低了9.4%和6.0%,峰值浓度明显降低,晚上出现峰值时间往后推移了2~3 h。经ADMS模型模拟计算,内环高峰时段机动车排放对主城区NO_2、PM、VOCs的浓度贡献分别降低了54.1%、56.3%、17.5%,CO浓度贡献不大。内环货车错时限行措施对重庆市主城区空气质量的改善有一定的积极作用。  相似文献   
35.
试验工况是否科学,可以通过对国内外常用试验方法的工况进行对比,发现其存在的差异性及侧重点,并通过调研对试验工况数据切合度进行验证。只有制定出合理的试验工况,才能为腐蚀数据库提供科学的数据支持。  相似文献   
36.
随着城市机动车保有量的不断增加,机动车尾气已经成为影响我国城市大气环境的主要问题之一。本文以儿童和交通警察两类人群为例,分析了机动车尾气污染给人体呼吸系统、免疫系统、心脑血管系统等造成的危害。结果表明,由于儿童的呼吸带与机动车尾气排放带非常接近,交警在机动车尾气环境中暴露事件太长,导致这两类人群的呼吸系统极易遭到破坏,发生支气管炎等疾病的概率大大增加;而免疫球蛋白水平和血压发生改变导致了抵抗能力的下降。最后建议通过采取发展公共交通、加强城市交通管理、完善检查维修制度等有效措施加强机动车尾气治理,减少对人体健康产生的危害。  相似文献   
37.
Refuse trucks play an important role in the waste collection process. Due to their typical driving cycle, these vehicles are characterized by large fuel consumption, which strongly affects the overall waste disposal costs. Hybrid hydraulic refuse vehicles offer an interesting alternative to conventional diesel trucks, because they are able to recuperate, store and reuse braking energy. However, the expected fuel savings can vary strongly depending on the driving cycle and the operational mode. Therefore, in order to assess the possible fuel savings, a typical driving cycle was measured in a conventional vehicle run by the waste authority of the City of Stuttgart, and a dynamical model of the considered vehicle was built up. Based on the measured driving cycle and the vehicle model including the hybrid powertrain components, simulations for both the conventional and the hybrid vehicle were performed. Fuel consumption results that indicate savings of about 20% are presented and analyzed in order to evaluate the benefit of hybrid hydraulic vehicles used for refuse collection.  相似文献   
38.

Problem

Motor-vehicle crashes are a leading cause of death in the United States. In the event of a crash, seat belts are highly effective in preventing serious injury and death.

Methods

Data from the 2006 Behavioral Risk Factor Surveillance System were used to calculate prevalence of seat belt use by state and territory and by type of state seat belt law (primary vs. secondary enforcement).

Results

In 2006, seat belt use among adults ranged from 58.3% to 91.9% in the states and territories. Seat belt use was 86.0% in states and territories with primary enforcement laws and 75.9% in states with secondary enforcement laws.

Discussion

Seat belt use continues to increase in the United States. Primary enforcement laws remain a more effective strategy than secondary enforcement laws in getting motor-vehicle occupants to wear their seat belts.  相似文献   
39.
北京电动出租车与燃油出租车生命周期环境影响比较研究   总被引:3,自引:2,他引:1  
燃油机动车尾气排放是导致城市包括雾霾在内的大气环境问题的主要来源之一.以电动汽车替代传统燃油车是当前各国解决城市大气污染问题的重要举措.北京于2011年启动了电动出租车推广计划.为比较北京市迷迪电动汽车和现代燃油车生命周期的环境影响,运用生命周期评价方法,基于Ga Bi4.4软件,选用CML2001和EI99影响评价模型对两款车的生产、使用和报废回收全生命周期过程的环境影响进行了定量评价,并针对汽车报废里程和电力能源结构进行了敏感性分析.结果表明,从全生命周期视角,根据EI99评价模型,迷迪电动汽车环境影响总体上优于现代燃油车,尤其在削减化石能源消耗方面优势凸显,但在生态系统质量影响及人体健康影响方面却略有增大的趋势;利用CML2001模型对比分析得出迷迪电动汽车比燃油出租车在对非生物资源消耗、全球变暖以及臭氧层损耗等方面有明显改善;但在生产阶段尤其是动力系统生产方面在非生物资源消耗、酸化、富营养化、全球变暖、光化学臭氧合成、臭氧层损耗、生态毒性等生态环境影响却均有增大趋势.使用阶段电力生产是迷迪电动汽车非生物资源消耗、酸化、富营养化、全球变暖、光化学臭氧合成、生态毒性等环境影响的主要来源;而现代燃油出租车使用阶段的环境影响主要来源于尾气排放和汽油生产,其中尾气排放是造成现代燃油车在富营养化和全球变暖等方面影响潜值较大的主要原因;基于清单数据库,针对致霾因子影响分析得出,在2010年北京市电力能源驱动下,迷迪电动车明显增加了超细颗粒物(PM2.5)、氮氧化物(NOx)、硫氧化物(SOx)、挥发性有机物(volatile organic compouds,VOCs)等因子的全生命周期的排放,而同时降低了氨气(NH3)的排放量,使用阶段排放的差别是造成上述趋势的主要原因.对关键因素敏感性分析发现,随着报废里程以及清洁能源比例的增加,迷迪电动汽车相对现代燃油车的单位里程碳减排量呈现增加的趋势.清洁电力能源的使用可大幅降低迷迪电动汽车致霾污染物的排放量.根据分析结果,为北京市电动车的推广提出了对策建议.  相似文献   
40.
The status of energy consumption and air pollution in China is serious. It is important to analyze and predict the different fuel consumption of various types of vehicles under different influence factors. In order to fully describe the relationship between fuel consumption and the impact factors, massive amounts of floating vehicle data were used. The fuel consumption pattern and congestion pattern based on large samples of historical floating vehicle data were explored, drivers'' information and vehicles'' parameters from different group classification were probed, and the average velocity and average fuel consumption in the temporal dimension and spatial dimension were analyzed respectively. The fuel consumption forecasting model was established by using a Back Propagation Neural Network. Part of the sample set was used to train the forecasting model and the remaining part of the sample set was used as input to the forecasting model.  相似文献   
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